Another Risk of Frost BUT a Nice Holiday Weekend Follows!

As the ongoing spring pattern persists; another large, cool high pressure system will settle over the Great Lakes and Northeast the next few days - and fortunately will dominate the Memorial weekend (see maps below). Look for temperatures to rebound nicely through the 70s and into the 80s mainly over the holiday weekend under fair skies.

Yep; there's the risk of frost in mainly outlying areas tonight away from Metro Detroit. A somewhat better risk of frost over Southeast Lower Michigan looks for overnight Thursday into Friday morning as winds lighten-up with the coolest temperatures aloft and surface. Any notable changes; I'll post an update.

Thursday Morn Map Thru Monday Morn, down.

Computer issues with my Summer Outlook; won’t boot up, hangs up. Try to have out by first weekend in June.



45 years ago Jan 26-27TH, 1978 ~ "A GREAT STORM IS UPON MICHIGAN"


Written by: William R. Deedler, Weather Historian - Southeast Lower MI

While I worked countless snowstorms in my long career with the NWS; the two most impressive storms were in order: the January 26-27, 1978 Blizzard and the December 1st, 1974 snowstorm. The huge snowstorm of December 1974 was quite noteworthy in the amount of snow that fell continuously for hours over the Detroit Metro area and portions of Southeast Lower Michigan.

A more powerful (in terms of intensity/extent) storm and remains of strong interest to all meteorologists who have studied winter storms in the Great Lakes is the January 1978 Blizzard. This storm is also of interest and remembrance to many longtime residents of the Great Lakes, the Upper Ohio Valley and Ontario, Canada who had to deal with winter's full fury late in January of 1978. In addition, the storm certainly casts many memories for those of us (author included) who were on duty and worked during the storm while observing in tremendous awe the development and subsequent immense strength of this great monster. With the 45th anniversary of this Great Blizzard at hand, it is worth taking a step back in time to re-live this monumental example of nature's fury.

While there are several contenders for the worst blizzard ever to hit the Great Lakes in relatively modern times (since 1870 when records began in Detroit), the immense and intense Blizzard of January 26-27th 1978 must rank at or near the top along with the Great White Hurricane of 1913 with its similar track and powerfulness.

The incredible Blizzard of January 26-27th, 1978 evolved out of a winter that was infamous for cold and storms. The Winter of 1977-78 thus far had been one the coldest, since records began, in many areas from the Rockies eastward to the Appalachians. Mammoth blizzards occurred late in January and early February from the Midwest to the East Coast as strong Arctic plunges dove south into the country and met up with the warmer winds from the deep south. The winter of 1977-78 was similar to its predecessor (1976-77) in terms of cold. The main difference between the two winters, however, came in February. In 1977, temperatures moderated rapidly during February, while in 1978, the cold actually worsened - with several locations reporting their coldest recorded February to date. The Winter of 1977-78 is written down in the record books as Detroit's seventh coldest winter, Flint's fifth coldest and Saginaw's sixth. West of the Rockies, it was a different story as a dominant upper ridge of high pressure provided a relatively mild winter, with some stations even reporting one of their warmest winters on record.

The Great Storm

Since there were some forecasting variances of the intensity and track of the storm, and considering the primitive model of the day (LFM - Limited Fine Mesh), forecasters did an admirable job in forecasting one of the most severe winter storms ever to hit the Great Lakes Region.

A Winter Storm Watch was posted as early as Tuesday night, the 24th, for the southern half of the Lower Peninsula for Wednesday Night into Thursday. Gale Warnings for the Great Lakes were hoisted the following Wednesday morning, along with the Watch. A weaker system had moved through the region earlier during the day on Tuesday and already dropped some snow on the region (a Winter Storm Watch had been issued for this system as well, earlier on Monday, the 23rd). After Tuesday's snow, the headline on the Special Weather Statement that was issued by the NWS Tuesday evening read as follows: "Another Winter Storm Threatens Lower Michigan" and thus, a second Winter Storm Watch was officially posted.

Meanwhile, the ingredients of what would later prove to be a truly fascinating yet vicious winter storm were coming together from different parts of the country. As with the "White Hurricane of 1913," the massive storm actually began as two smaller but distinct storms. A strong low pressure with an attending arctic air mass was entering the Northern Plains by way of Northern Minnesota on Tuesday evening (24th). At the same time, another developing low pressure system was taking shape over the eastern Texas/Louisiana area.

The phasing of two distinct jet streams aloft proved to be the key as to the subsequent strength and massive extent of the storm. A very strong and energetic Arctic impulse surged almost due south and plowed the Arctic front through the Northern Plains late on the 24th. At the same time, another very strong upper wind impulse surged south through southern Arizona. These two jet streaks made up the larger North American jet stream as a huge upper ridge of high pressure along the West Coast of the U.S. diverted the powerful Pacific Jet north into Northern Canada. This northern jet (containing a wind max of 110 knots) then dove due south, like on a giant roller coaster, across the western U.S. as the second, subtropical jet (with an even stronger wind max of 130 knots) surged across southwestern states. On Wednesday (25th), a deepening area of low pressure made its way east across the Gulf States into Georgia by evening (surface | 500mb). Meanwhile, across the north, the Arctic front barreled east across the Upper Midwest into the Western Lakes by Wednesday evening.

Earlier that Wednesday morning, the Winter Storm Watch for Southeast Lower Michigan was changed to a Heavy Snow Warning, while a Travelers Advisory was issued for Western and Northern Lower Peninsula. Later, at the issuance of the evening forecast, the entire Lower Peninsula was upgraded to a Heavy Snow Warning. Meanwhile, a rapid deepening of the surface low over the southeast portion of the country also commenced on Wednesday evening. As the low intensified over Alabama and Georgia, Atlanta registered its lowest barometric pressure ever late on the 25th. At the same time, further north in Michigan, snow was falling over much of the Lower Peninsula. In and around the Ann Arbor and Metro Detroit, the snow mixed with or changed to light rain Wednesday night as slightly warmer air surged northwest into that area ahead of the deepening storm.

While the storm was organizing in the lower levels of the atmosphere over Georgia, the Subtropical and Arctic jet aloft began to merge and phase over the Southeast part of the country. This merging of jet streaks contained a wind max of 150 knots which helped induce a rapid intensification of the Georgia Low as it surged northward into West Virginia early on the 26th. Record low barometric pressures were set all along its path as an ominous track (trough) began to materialize toward the Eastern Great Lakes.

Bands of heavier snow spread north into much of Southern Lower Michigan during the very early morning hours of the 26th. Rain continued to fall, however, over the extreme southeast corner of Lower Michigan. At 1 AM EST, rain was observed at Detroit Metro Airport with the temperature comfortably above freezing at 36 degrees. Further north at Flint, however, sleet and freezing rain were falling as the temperature hovered around freezing. Air pressure tendencies were noted as falling rapidly /PRESFR/ and continued that way for several hours (in fact, several stations in this storms path had to re-adjust their barographs for station pressures traces that were BELOW initial chart scale).

The aforementioned Arctic cold front that was across the Western Great Lakes advanced steadily east into Lower Michigan as the main southern low underwent explosive deepening (this low's central pressure fell 40 millibars in 24 hours)! The central pressure was recorded at 28.28 inches as it tracked north across eastern Ohio, just west of Cleveland, at 7AM EST. As the low moved out over Lake Erie, the Arctic cold front over Southeast Lower Michigan was pulled sharply east into it's mammoth cyclonic circulation. Any residual rain over Southeast Lower Michigan quickly changed to heavy snow and blowing snow during the pre-dawn hours of the 26th. As the Arctic front plowed through the Cleveland area, the wind gusted to an incredible 82 mph! As the Arctic air flooded the Cleveland area, the temperature dropped from a relatively balmy 44 degrees at 4AM EST to a bitterly cold 7 degrees by 1000 AM EST.

Blizzard Warnings were hoisted across much of the Great Lakes and Upper Ohio Valley Region by daybreak Thursday. The center of the huge storm (surface | 500mb) continued to trek north northwest across Southwest Ontario (roughly between Chatham and London) while Detroit measured its lowest pressure reading at 28.34 inches at 650 AM EST. The incredibly deep center made its way north along the St. Clair River with Sarnia ON reporting the lowest pressure on land at 28.21 inches. Not only was the depth of this mammoth storm's center very impressive, so too was the extent of low pressure from its center. Even locations that were far removed from the storm's center also reported record low pressures. Stations such as Cincinnati OH, Rochester NY and Toronto ON and even as far east as Wilmington N.C., all recorded record low pressure readings from this monster. In fact, at Toronto, where records go back as far back as 1840, the lowest pressure reading of 28.40 inches broke the old record of 28.57 inches by 0.17 inches. In addition, dozens of other cities, with records going back a century, also recorded their lowest pressure reading of all time or, for at least the month of January. This massively intense storm was responsible for strong wind gusts as far away from the center as Boston /72 MPH/ and Chesapeake Bay Bridge /90 MPH/ with even damaging winds reported as far south as Tallahassee FL.

As the Arctic air circulated throughout the storm while it made its way over Lake Huron, the lowest pressure was reached around 950 millibars or a hurricane-like 28.05 inches! "A Great Storm is Upon Michigan" read the headline of the 800 AM EST Special Weather Statement issued by the National Weather Service Forecast Office in Ann Arbor that Thursday /26th/ morning. Heavy snow and blizzard conditions were extensive as wind gusts in excess of 35 mph whipped the snow into huge drifts across much of Southeast Lower Michigan. Other areas of Eastern Michigan, Indiana and Ohio reported near hurricane-force winds, heavy snow and temperatures hovering between zero and 10 above, resulting in extreme blizzard conditions. These conditions later expanded further east into Pennsylvania and West Virginia and prevailed into the night (26-27th) across much of the Eastern Great Lakes, Southern Ontario and the Upper Ohio Valley. With the storm generating copious amounts of snow and very strong winds, whiteout conditions were widespread. All land and air traffic came to a stand still in the affected regions. Several major roads were closed for at least two to three days, if not longer, while clean up got underway. Numerous NWS employees were stranded at work, home, or on the road somewhere between the two. Several employees worked double shifts into at least Friday (some longer) because of the impassable roads with others simply unable to get to work.

The Blizzard Warnings were allowed to die across Michigan during the forenoon hours of Friday, the 27th. Record 24 hour snowfall totals from the storm included, 16.1 inches at Grand Rapids, 15.4 inches at Houghton Lake and 12.2 at Dayton, OH. Snowfalls for the entire storm (25-27th) included a whopping 30.0 inches at Muskegon (some of which was Lake Michigan enhanced), 19.3 inches at Lansing and 19.2 at Grand Rapids. Snowfalls were less over Southeast Lower Michigan (mainly because of the rain that fell for a period) and included 9.9 inches at Flint and 8.2 inches at Detroit.

The following is a quote from the summary written about the storm by Meteorologist in Charge, C.R. Snider on January 30th, 1978 at the National Weather Service Ann Arbor:
"The most extensive and very nearly the most severe blizzard in Michigan history raged throughout Thursday January 26, 1978 and into part of Friday January 27. About 20 people died as a direct or indirect result of the storm, most due to heart attacks or traffic accidents. At least one person died of exposure in a stranded automobile. Many were hospitalized for exposure, mostly from homes that lost power and heat. About 100,000 cars were abandoned on Michigan highways, most of them in the southeast part of the state."
The employees of the National Weather Service Forecast Office in Ann Arbor had just set up shop at the new quarters at the Ann Arbor Federal Building a WEEK before the storm hit. The forecast staff had transferred from the Detroit Metropolitan Airport Office while the observing and radar staff remained at the airport. The majority of employees still lived in and around the metro Detroit area and all major roads between Detroit and Ann Arbor were blocked for approximately 18 hours due to the storm. Several employees put forth efforts beyond the call of duty, stated Mr. Snider in his storm report.

Yet, as mentioned earlier, the Winter was not yet over by any means as the month of February (after the storm) was brutally cold across much of country. The below normal temperature departures of February 1978 were strikingly similar to that of January 1978 (and in some places, February was actually colder). The average temperature for Detroit that winter came in at just 20.5 degrees /normal 27.1/ which again, made it the seventh coldest winter on record. Snowfall totaled a hefty 61.7 inches which made the winter of 1977-78 the ninth snowiest winter on record in Detroit at that time. Flint's average temperature of 19.1 degrees made it the fifth coldest winter on record, but Flint received less snow than Detroit with 50.6 inches. Saginaw's winter average temperature of 17.9 degrees made it the sixth coldest winter on record and was accompanied by 55.6 inches of snow. The 1977-78 snow season at both Flint and Saginaw has since dropped off the top 20 snowiest winters list.

More on the storm in surrounding areas can be found here.



Making weather fun while we all learn,
Bill Deedler -SEMI_WeatherHistorian



Winter Storm to Blow Through With Less Snow Fan-Fare /Update 3PM Thu 12/22/22/

The Pre-Christmas storm is still expected along and back behind the the Arctic front moving through overnight into Friday. Warmer air ahead of the storm center will allow more rain to fall and less snow on the back-side of the system. Majority of models bring the change over around midnight Thursday and create icy road conditions and strong winds Friday morning into Friday.

What's still threatening with the system is the strong, frigid winds accompanying the backside of the storm. Wind gusts will be strongest on Friday and Friday night; possibly reaching the 40 - 50 mph range. Major concern will still be flash freezing on the roads creating hazardous driving conditions along with local power outages, certainly a risk.

Yesterday I stated; 

I've posted parts of the the GFS and Euro /12z/ just to give an idea of the range of weather conditions projected at this time /Wed-2pm/. At this time I'd side closer to the European expectations for weather conditions and local snow amounts with GFS greater than and also less than the European.Variability in intensity, location, movement resulting in duration and precipitation (snow ratios) is causing a variation in model output.

This is the case with guidance; I still prefer the European and snowfall totals have come down a notch for a few reasons. The system is moving faster; a subtle dry-slot behind the occlusion is a risk and more rain is expected ahead of the low/front. Even lower amounts of snow are showing up on a few models in the metro Detroit area /1-2"/; we'll see if this materializes. The range and intensities of this system for days has been a nightmare on the models. 

Checking latest preferred Euro guidance:



Generally 2-4" of snow is expected around the Metro Detroit area with 4-6" over the western/highland regions and downwind of lake Huron. Some pockets of higher snow amounts are possible; especially with Lake Effect snow into Saturday.   

Making weather fun while we all learn,
Bill Deedler - SEMI_WeatherHistorian




Major Winter Storm to Impact The Great Lakes Region Including Southeast Lower Michigan Pre-Christmas Period

Traveling during the period overnight Thursday /22nd/ into early Christmas Eve /24th/ will be challenging especially Friday into Friday night. Sharply colder air will blast the region early Friday as the storm center intensifies and "bombs out" over the Southern Great Lakes. To be considered a bombogenensis event the central pressure of the low pressure would have to deepen 24 MB in 24 hours by definition. It should come close to or exceed that as the center gets into the region. 

What's really threatening with the system is the strong, frigid winds accompanying the storm. Wind gusts will be strongest on Friday and Friday night; possibly reaching the 45 - 55 mph range. Major concern will be flash freezing on the roads creating hazardous driving conditions along with damaging winds and local power outages, certainly a risk.

While most snow amounts shouldn't be on the higher side (better than a foot) as with most major storms over Southeast Lower Michigan; snow totals likely will range from 4" - 9" with the highest amounts over the western/highland regions and downwind of lake Huron. I've posted parts of the the GFS and Euro /12z/ just to give an idea of the range of weather conditions projected at this time /Wed-2pm/. At this time I'd side closer to the European expectations for weather conditions and local snow amounts with GFS greater than and also less than the European.

It should be noted here that this is under the assumption the low will be progressive and move fairly quickly through the Southern and Eastern Great Lakes. I am concerned about the low pressure deepening and holding a bit longer over the Eastern Great Lakes/Southeast Lower Michigan/Lake Huron region. This would enhance snowfall with Lake Effect snow with the bitter cold wind extending from the Lake down across the Thumb Region Southward into parts of Metro Detroit. The Great Lakes are relatively warm with the normal to mild fall and the lack of intense storms; resulting in somewhat less temperature mixing of deeper waters. The relatively warmer Lakes are a favored region; especially in the fall into winter for low pressure intensification and thus; breeding ground for these storms.

Variability in intensity, location, movement resulting in,duration and precipitation (snow ratios) is causing a variation in model output.  In any event; the Arctic blast will cause extensive blowing and drifting snow with local ground blizzard (little of no snow falling) conditions creating whiteouts with limited visibilities.

 GFS Thursday Eve thru Christmas Day

 EURO Thursday Eve thru Christmas Day

GFS Upper Wind Jet Structure Thursday Eve thru Christmas Day 

EURO Upper Wind Jet Structure Thursday Eve thru Christmas Day 

GFS Snowfall Thursday Eve thru Christmas Day

EURO Snowfall Thursday Eve thru  Christmas Day

Look for an update Thursday and Friday before the Christmas Holiday

Making weather fun while we all learn,
Bill Deedler - SEMI_WeatherHistorian


 The Whitest of Christmases and Other Christmases Past and Chances for a White Christmas - 2022

Frequently during the Christmas Season, meteorologists are asked; Are we going to have white Christmas?  Generally, it is agreed among meteorologists that in order to "officially" have a white Christmas, an average of an inch of snow must cover the ground Christmas morning /7AM/, but not necessarily have to fall on Christmas. 

At this time /Monday/; December 19th 2022 chances of a white Christmas across all of Southeast Lower Michigan continue "to change with every model run" (I love it, this was the line I sent out last year). Seriously; as of the latest run trend; all areas should see the needed inch of snow on the ground Christmas morning. 
❅❅❅ ⛄ A major winter storm is brewing on all models for later this week as Christmas approaches ~ snow and rain, then snow, strong winds and hazardous, icy traveling conditions. More on the storm in the next few days when the sampling of the atmosphere mid week gets better. ⛄❅❅❅ 
Last Christmas /2021/ we ended up with no white Christmas. Christmas 2020; we lucked out with generally an inch or two of snow falling over the region on Christmas Eve into Christmas morning. A nice picture-perfect light snow cover.
Christmas /2019/ no white Christmas was to be had - and also back in 2018; around Metro Detroit there was no white Christmas. In fact; temperatures pushed up into the 40s and 50s in the few days following Christmas. Further north from the Flint area into the Saginaw Valley and Thumb Region however; a inch or two remained on the ground for a white Christmas across that region.

Over the years, extreme Southeast Lower Michigan has averaged just under a 50 percent chance for a white Christmas.  Some years it's already on the ground, some years not, some years it melts while other years it falls on the day. However, theoretically, you could actually have nothing on the ground Christmas morning and have a snowstorm dump a foot on the region during the day and still have NO official white Christmas under the standing morning rule. It works the other way too; you could have a several inches on the ground at 7am 12/25 but warmer air and/or rain melts it away by afternoon or evening and still officially have a white Christmas.

Four years ago /2017/; an unexpected white Christmas was had in spades as low pressure system overachieved; developing robustly over the southern Great Lake/northern Ohio Valley. The system developed into a notable little snowstorm falling mainly on Christmas Eve over the southeast area as seen in this map, bringing snow for a picturesque, classic Christmas scene. The only negative - and a notable one - was the lousy driving conditions Christmas Eve into early Christmas Day but with improving conditions later for Christmas dinnertime.

For more on the system from the NWS; see here.

In 2016; even with mild weather with temperatures in the 30s; Southeast Lower Michigan was able to hold on to a white Christmas as the snow (generally 2-5") slowly melted. In fact; the day after Christmas, warm air surged into the region and pushed temperatures into mainly the 50s and took care of any remaining snow! Back in December /2015/; it was a mild and snowless Christmas with a high temperatures near 50. Of course, the year before, /2014/ contained our record breaking warm El Nino December, therefore the hopes for a white Christmas were low anyway. Back on Christmas 2014, the chances for a white Christmas were very similar to 2015 with record setting low amounts of snow for the month (in the top 5 snowless). Officially on 12/25/14 at 7am; no snow was on the ground with a trace of light rain on the date. Only a TRACE of snow had fallen up to that day in December /0.1 for the entire month/.  Most areas over the remainder of Southeast Lower Michigan had a few tenths of snow Christmas eve or Christmas but with less than the amount needed and mild temperatures rising into the upper 30s to around 40...none of the area saw a white Christmas.

More Previous Christmases back to 2004:

In 2013;  even with all the snowfall throughout last winter, officially on 12/25/13 at 7am Detroit Metro Airport had only a TRACE of snow on the ground. Most areas into the remainder of Southeast Lower Michigan had some residual snow and ice on the ground for a white Christmas. Back in 2012, enough snow did fall at Detroit Metro Arpt (an inch of fresh snow Christmas Eve) to make it an official white Christmas was on the ground as of 7AM. The necessary inch or more was also on the ground at both Flint and Saginaw. Ironically the day after Christmas, the best snowstorm of the winter season hit the region...a day late and several inches short for Christmas. A year earlier in 2011, it was a relatively mild Christmas with temperatures in the 40s and no snow on the ground; so no white Christmas. However back in 2010; residents across Southeast Lower Michigan did enjoy a white Christmas with generally 1” to 6” of snow across as temperatures hovered in the 20s. Then further back in 2009, much of the Detroit area south did not have a white Christmas but points north across Flint, Saginaw and the thumb region generally had a 1” to 3” snow cover. Back in 2008, we saw a “sloppy, melting white” Christmas. That white Christmas involved the melting of a heavy snow cover from past snows that accumulated throughout December. The best of the snowstorms came before Christmas on the 19th (with another, lesser intense snow falling on the doorstep of Christmas, 23rd -24th). After, however, the heavy snow cover melted in earnest as milder air overspread the region Christmas Eve right through the 26th. Christmas of 2007, saw temperatures rise into the mid 40s to mid 50s a couple of days prior to Christmas and that, combined with light rain, pretty much took care of any hopes for a white Christmas as then, like the later Christmas of 2008, the  previous heavy snow cover melted (but this time in its entirety before Christmas). Some scattered light snow did return, skirting the landscape on Christmas Eve but most areas around Southeast Lower Michigan still only had a trace of snow for Christmas. At White Lake and Saginaw, however, the official inch of snow to make it a white Christmas was barely attained in 2007.

Going back further to the Christmas of 2006; it was also mild and therefore, there was no white Christmas. In 2005, we just barely squeaked out a white Christmas (at Detroit Metro Airport, anyway) as a mild spell moved in just before Christmas along with rain, melting the snow down from 4” to 1” by Christmas morning. Originally, there had been 8” of snow on the ground on the 15th. The last really scenic (no slop)  with fresh white snow for Christmas occurred in 2004. A snowstorm brought heavy snow (ranging from 8”at Detroit to around 4” in Saginaw and Flint) on the 23rd, which left the region with a nice white cover for Christmas. It was also a cold Christmas also with highs only in the teens and overnight lows below zero. 

Looking over historical weather records of Christmases past since 1900, a wide range of weather conditions were found. While most people would like to believe that Christmas in the Detroit area should be snowy-white and picturesque, more often than not, they're not. Over the past 121 (including 1900) Christmases in Detroit, 57 (or 47%) have been what would be called "white" with an inch or better of snow on the ground. Keep in mind however, these records are for Detroit; farther north in Flint, the chance of a white Christmas jumps to 56 percent, while in Saginaw and the Thumb region it rises to 61 percent.

  Recently, the Christmas of 2000 was very white indeed, but as to how much of a white Christmas (snow depths) is where the confusion came in. Let me elaborate, officially at Detroit Metro Airport, just six inches of snow was recorded on the ground at 7AM Christmas Day. However, just about anywhere west/north and in the city of Detroit itself, amounts were considerably higher with generally 8 to at least 15 inches. At the National Weather Service in White Lake, 15 inches was observed on the ground Christmas 2000 morning. No additional snow fell on Christmas Day (nor was anymore really wanted with the surplus already at hand). In any event, for Detroit and surrounding communities, the six inches at Detroit Metro Airport is the official snow depth used for the area.

The snowiest Christmas (most snow falling on Christmas), occurred in 1915 when 6.4 inches fell with a snow depth of seven inches on the ground. The timing of this snowfall was impeccable for Christmas with it actually starting Christmas Eve around sunset. Then, it continued to snow through the night into Christmas day. Actually, even more than the 6.4 inches fell from the entire storm with an additional 1.6 inches falling on Christmas Eve. This gave a snowstorm total of eight inches.  A little light rain did mix with the snow during the forenoon hours of Christmas but with a high temperature of only 33, it did little to mar the "Christmas card" scene. Speaking of "Christmas card" scenes, another heavy wet snowfall blanketed the area just after the turn of the century early on Christmas in 1901. The scene is described in the historical weather books as follows:

    "Night of the 24 - 25 cloudy; moist snow continued,
     heaviest between hours of 1:30 and 4:30 am, ended
     at 6 am. amount of precipitation .62 inches. The
     street cars ran all night to keep the tracks open.
     the snow adhered to trees etc, and made a very
     beautiful scene. Depth of snow on ground at 8 am,
     5.5 inches".

 This "Norman Rockwell Christmas scene" was further enhanced by a heavy coating of frost deposited on the buildings and windows Christmas Eve due to the moisture-laden air. But just like memories of some Christmases past, this majestic Christmas scene quickly faded (melted) during the day as temperatures climbed to 41 degrees, leaving just slush , slop and water. During the Christmases of 2002 and 2003, the weather was similar to both of the white Christmases mentioned above /1901 & 1915/. Here again in 2003, snow started falling Christmas Eve and lasted into at least part of, if not all of Christmas Day. On Christmas Day 2003, snowfalls ranged from at least an inch in the far southeast corner of Lower Michigan to as much as six inches across Detroit's northern suburbs, extending northward across Flint and Saginaw. On Christmas Day of 2002, total snowfall at Detroit Metro Airport was measured at 6.4” inches for both days (Christmas Eve and Christmas) with 3.4” of it falling on Christmas Day, itself. Across all of Southeast Lower Michigan snowfalls generally ranged from four to seven inches. A picture perfect Christmas was created both years with the freshly fallen snow. Like the Christmas snowstorms of 1901 and 1915, the snow Christmas 2002 was also somewhat heavy and wet with high temperatures in the lower 30s and lows only in the mid 20s.

Probably one of the slushiest and sloppiest Christmas Days happened in 1973. What started out as a white Christmas with a heavy 7 inch snow cover, quickly melted to a meager 2” slush mess by nightfall. To add insult to injury, it rained nearly a half an inch during the day.The wettest Christmas on record occurred in 1945 when 1.16 inches of rain fell. The rain actually began Christmas Eve as a light freezing rain and continued freezing until nearly dawn on Christmas, when the temperature pushed above freezing. Until the ice melted, a few tenths of an inch of ice coated everything by Christmas dawn. Needless to say, walking and driving early the Christmas of 1945 was treacherous but Santa was in and out of town in a flash!

Without a doubt, and still in the memories of long term inhabitants of Southeast Lower Michigan, is the warmest Christmas on record, the Christmas of 1982. It was as though the whole area was shipped to Florida for the holiday! The official record high at Detroit was 64 degrees, while Flint did one degree better at 65! These readings are about normal for Tallahassee, Florida! Scenes of shirt sleeved people with shorts running or riding bikes, instead of visions of sugar plums, made the Christmas of 1982 to some Michigan Christmas traditionalist, very hard to take.  This spring-like day was complete with scattered showers and, of all things, thunderstorms! Ironically, the bitterest cold Christmas came just a year later in 1983! Maybe a payback from Mother Nature for the warm weather we were treated to, the Christmas past? The temperature plummeted Christmas eve to a record low of -9 at Detroit and was accompanied by a stiff west wind averaging 25 to 30 mph, creating life threatening wind chills at times of near 40 below zero! Santa certainly brought the North Pole with him the Christmas of 1983, when he made his rounds very early that morning. In addition to the record low Christmas eve, another record low /-10/ was established during the very early morning hours of Christmas.

These Christmases past discussed are more the extreme than the norm across extreme Southeast Lower Michigan. But they do show the variable weather that can occur at Christmas (or any other time for that matter). The "normal" (or average) highs in extreme Southeast Lower Michigan Christmas Day are in the lower 30s, while lows average in the upper teens.

And now, I'd like to wish all who read this a very Merry Christmas and/or Holiday Season and the best in 2023!  I plan on continuing my blog for the new year if the fates allow and look forward in reaching out to more people (and hear their comments and ideas) across the globe.

Making weather fun while we all learn,
Bill Deedler - SEMI_WeatherHistorian


Now That One Of The Driest Autumn's Has Passed - What Does The Computer Guidance Say For The Winter?

Mom Nature gives and takes away - and that's certainly the case this past fall (and year). In recent years; the abundance of precipitation at least partially, resulted in the Great Lake flooding levels. On that note; Great Lake and adjoining rivers levels have notably receded in the last year or two. See an update on the Lake Levels, October 2022. The drop in precipitation so far this year is the most seen in several years in metro Detroit. Last time we were significantly below normal was in 2012 for Detroit with 27.12" (still not even close to this year's thus far; 21.97") and Flint at 22.61" a ways from 2010 /25.57"/  thus far.  Saginaw just over 2010 /25.57"/ with current total /25.97"/. The last time Detroit's precipitation was this low was 20 years ago in 2002 /22.14"/. Again note; these are all entire year's totals and all should be over current annual totals. Finally; little change has been noted the first few days of December.












Making weather fun while we all learn,
Bill Deedler - SEMI_WeatherHistorian


Third La Nina Winter ~ Triple the Weather Variety ~ Winter Weather Early and Aggressive?

After beautiful spells of Indian Summer weather in a delightful but abnormally dry autumn; there's a change in the offing - commencing now, this mid November. Models are progging aggressive cold fronts (of varying degrees) to drive south into much of the country east of Rockies through the upcoming week and at least through the next weekend. The veritable "Summer to Winter" familiar narrative looks appropriate for mid month. Recent record or near record temperatures in the 60s and 70s will fall into the 40s, 30s & 20s.

The projected 500 MB polar projection for November 2022 as of the 9th is below. Both the Polar/Arctic jet and the Pacific jet (Sub Tropical) are displayed for the the remainder of the month and I feel basically; for the winter period.


On to the Winter Outlook...



Upper Air/Surface Patterns and subsequent chosen La Nina analogues; suggest normal to slightly below normal temperatures or +1.5 to -2.0 of the new 1991-2020 norms. See analogue section for particulars.



Upper Air/Surface Patterns and subsequent chosen La Nina analogues; suggest normal to locally above the new 1991-2020 norms snowfalls and precipitation. See analogue section for particulars.


Hemispheric Layout

La Nina conditions just keep hanging around in the Pacific. So much so, the Winter of 2022-23 will be the third consecutive La Nina winter to occur since the first in the current set, 2020-21. In the past 130 years, this has only happened four times since the late 1800's. Each three La Nina sets are in the following order with the third La Nina highlighted.

















While La Nina winters have their own set of weather trends across the country; they can vary or be influenced by many other factors, sometimes to the extent they resemble little of the initial La Nina climate/weather standard trends. This is why I feel it is more important to compare "apples to apples rather than bushels to bushels" What do I mean? In my chosen and emphasized analogues; I research the timing, type, and stronger relevance to the up coming La Nina (and in this round; third La Ninas highlighted) rather than all La Nina's in the past century or so. This brings up another relevant point. The majority of La Nina's used in analysis are only since 1950. Why? Because some the data from the later period is based on measured data; especially in water temperature and departures. Instead of trying to explain why I use data at least back 100 years; I'll let the experts explain it. Please read the full article because it is interesting and explains the larger data set which goes back a "century" further to 1854 rather than 1950. The following is excerpts from NOAA Climate.gov "

Exactly the same, but completely different: why we have so many different ways of looking at sea surface temperature

ERSSTv4 goes back to 1854 (although due to a lack of observations in the Pacific Ocean, for El Niño purposes, the dataset reliably goes back to only 1950), and scientists have already put in a lot of time and effort to make this dataset consistent regardless of era (2). So why do we need another one? The easiest answer is that our seasonal climate models don’t run just once a month, but daily. Not surprisingly, they produce better forecasts when they are launched (we say “inititalized”) with a more detailed, more up-to-date view of what the oceans look like at that time.

For this situation, we want as much information as we can get it regardless of the historical consistency. So we rely on a dataset that combines in situ measurements with near-real-time satellite measurements. Satellites are not equipped with magical space thermometers that can measure the ocean temperature directly. Instead, instruments on the satellite detect energy radiating from earth to space. We use algorithms, physics equations and estimations to calculate what the sea surface temperature must have been to generate the amount of energy the satellite detected.

So the next time you want to compare the strength of this El Niño with past historical cases, use the ERSSTv4 dataset, compiled from buckets, boats, and buoys. That is what it was created for. But if you want to see the smaller-scale spatial and more frequent temporal changes of sea surface temperatures that occur within an event, OISST is more useful.

ERSST stands for the Extended Reconstructed Sea Surface Temperature dataset and is updated and maintained by our colleagues at the National Centers for Environmental Information.

 La Nina   La Nina   La Nina

Autumn thus far has contained classic La Nina weather with drier than average fall weather and normal to above temperatures. Plenty of sunshine along with average frost/freeze days rounded off the overall, pleasant weather. Checking the previous La Nina, autumns in our current set of analogues shows the past weather (Temps/Pcpn):

As we move into the winter; a weak to moderate La Nina will prevail across the Pacific and influence the climate and weather patterns over North America.

Late October La Nina SST conditions


Model La Nina Forecast

Types of La Ninas related to placement of colder, below normal Pacific water temps

Thus far the projection for the La Nina is for the coldest departures to be located in the central-eastern Pacific, closer to the resultant seasonal to colder winters (1st and 2nd examples).


Pacific Decadal Oscillation /PDO/ and associated subset EPO

Late October Pacific water temperatures (map 1, above) indicate closest semblance oscillation phase is currently a negative PDO. Note the negative /-PDO/ below on both collection of maps. Generally, a negative PDO coincides with a La Nina (as seen on the negative PDO anomaly pattern map).


Temperatures across Southeast Lower Michigan on the prevailing negative PDO map are normal to slightly above (last map).


Currently; the Pacific Decadal Oscillation is settling into a cool phase and is represented on the right of the following example; and, compare it to the current state. The cool phase PDO on the right contains a large area of warmer waters extending from Japan east to the mid Northern Pacific. Waters along the Alaskan and Pacific coastline tend to cool somewhat leading to the cool phase.


                      Warm Phase of the PDO         Cool Phase of the PDO


 "When SSTs are anomalously cool in the interior North Pacific and warm along the Pacific Coast, and when sea level pressures are below average over the North Pacific, the PDO has a positive value. When the climate anomaly patterns are reversed, with warm SST anomalies in the interior and cool SST anomalies along the North American coast, or above average sea level pressures over the North Pacific, the PDO has a negative value" (Courtesy of Mantua, 1999).

"The Pacific Decadal Oscillation (PDO) is a pattern of Pacific climate variability similar to ENSO in character, but which varies over a much longer time scale. The PDO can remain in the same phase for up to 20 to 30 years, while ENSO cycles typically only last 6 to 18 months. The PDO, like ENSO, consists of a warm and cool phase which alters upper level atmospheric winds. Shifts in the PDO phase can have significant implications for global climate, affecting Pacific and Atlantic hurricane activity, droughts and flooding around the Pacific basin, the productivity of marine ecosystems, and global land temperature patterns. Experts also believe the PDO can intensify or diminish the impacts of ENSO according to its phase. If both ENSO and the PDO are in the same phase (as in this and last Winter of 2021-22), it is believed that El Niño/La Nina impacts may be magnified. Conversely, if ENSO and the PDO are out of phase, it has been proposed that they may offset one another, preventing "true" ENSO impacts from occurring". 


Two years back, during the Winter of 2020-21 and our first La Nina of the current three, water temperatures of the La Nina and PDO were out of phase. As it turned out; the winter was indeed notably warmer than what is generally seen in a La Nina winter. This possibility was mentioned in the write-up of the Winter Outlook 2020-21 and one of the reasons noted that may interfere with the normal LA Nina winter jet and temperature pattern.

The evolving cold phase of the PDO this fall and weak La Nina are displayed well in this recent Global SST scan on October 29th, 2022, below.

 Eastern Pacific Oscillation /EPO/

The Eastern Pacific Oscillation /EPO/ is a variation in the atmospheric flow pattern across the eastern Pacific many times into Alaska. When the EPO is in a positive phase, mild Pacific air flows straight into the West Coast of North America. When the EPO is in a negative phase, a ridge forms in the upper winds along or off the West Coast over the eastern Pacific.

North Atlantic Oscillation/Arctic Oscillation - NAO/AO

 As usual; this should be one of the most important meteorological influences for this winter. In the last few years, it's had an on and off again effect on our weather, working with Stratospheric warming (delivering cold air to the surface) and the EPO. Refreshing our memory on this little number shows why it is the major influence with our weather.

 +AO(NAO) and -AO(NAO) explained:
The Arctic Oscillation is tracked by observing 1000-millibar geopotential height anomalies over the far upper latitudes of the Northern Hemisphere, above 20 degrees North to be specific. The AO has two phases: a positive phase, and a negative phase. When the AO is said to be positive (+AO), geopotential height anomalies over the upper latitudes are lower than normal. This means the tropospheric polar vortex is stronger than normal, and this stronger vortex “locks up” the colder air at the upper latitudes, keeping it from flowing south. As a result, a positive AO is associated with above-normal temperatures in the United States. When the AO is said to be negative (-AO), geopotential height anomalies over the upper latitudes are higher than normal. This means the tropospheric polar vortex is weaker, and enables colder air masses to flow down to lower latitudes. As a result, a negative AO is commonly associated with below-normal temperatures in the United States.



Generally when the NAO/AO index is in the positive phase; more zonal winds dominate as the polar vortex lifts up toward or over it's home, the North Pole region. However; when in a negative phase; the cold vortex or wind flow is more meridional and thus; cold Polar or Arctic air is readily pushed south from the Pole; down into the eastern half of the U.S. (among other Northern Hemisphere areas). Many times ridges of higher pressure develop in conjunction on the North American west coast and/or into Greenland. 



 Siberia/Eurasia /North America Snow Cover 

One of the studies by Dr. Jonah Cohen uses October snow-cover over Siberia/Eurasia to aid in projecting out the main phase of the NAO and likely corresponding temperature pattern for the winter. Recently, early November is also considered in the comparisons sometimes.

The snow-cover over Siberia has actually been less than average until right at the end of October when it became slightly above normal. The first week of November was above normal. 

From recent Dr Jonah Cohen

As can be seen from Figure i, the SCE was relatively low the entire second half of the month.  But please keep in mind of all the years shown in the plot, only 2011 was below normal so, 2022 is low relative to recent years but high compared to the long-term average.  And I have been estimating over the past month, the final number will still likely come in slightly above normal due to the fast start to the month. 

In Figure ii, I present the timeseries for Eurasian mean October SCE anomalies since 1979 and 2022 was slightly indeed above normal.  In fact, it is very similar to the observed values for the past two Octobers.  It is my impression that El Niño does favor a faster advance of Eurasian SCE than La Niña, and it could be the three-peat La Niña has suppressed the SCE the past three Octobers, albeit at historically high values.


Quasi-Biennial Oscillation /QBO/


The QBO, or Quasi-Biennial Oscillation, is an oscillation in the wind direction in the stratosphere within about 15 degrees of the equator. Over a roughly two-year period, winds tend to oscillate between westward and eastward, with the switch between west and east winds starting high in the stratosphere and then shifting lower in altitude with time. The QBO is the result of waves propagating vertically in the atmosphere that then interact with the mean flow to slowly change wind speeds and direction. These changes influence the overall global circulation patterns, which in turn influence winter weather patterns across North America. 
If you notice on my analogues; I included the QBO's for each available winter and compared it to the upcoming winter's QBO phase and trend. The present and expected QBO this winter is for a light to possibly moderate westerly wind.  The set of maps below show the differing influences of the QBO dependent on phase and trend. The QBO is presently in the light westerly (closest being maps in sequence; D).



Finally, a new kid on the block in my write-up; see the video from the Met Office in England (click on "What is the Atlantic Multidecadal (AMO).  I've known about the AMO since I started my outlooks but since the effects are mainly east especially in the Winter Outlook, I left out of my discussions. Like all Oscillations; the AMO does occasionally affect the Great Lakes. 


Solar cycle actual effects on short term weather and longer term climate variability remain a controversial subject. I've read several articles which support or are against their shorter term winter relevancy. Some theorize that both natural solar cycles and man's influence affect our climate. I am in favor of the solar cycle being somewhat relevant and sometimes giving the present winter cycle a "little kick" in regard to hemispheric wind flow patterns and resulting temperatures.  Numerous recent studies for example, do in fact make the connection to our climate and solar activity including wintertime effects. One of the studies stated the following:

 "The Euro–Atlantic sector seems to be a region with a par-
     ticularly strong solar influence on the troposphere. In fact,
significant positive correlations between solar activity and
   surface temperature in Europe have been reported in several
 papers (e.g. Tung and Camp, 2008; Lean and Rind, 2008;
 Lockwood et al., 2010; Woollings et al., 2010), although
  long records tend to give very weak signals (van Olden-
    borgh et al., 2013). We found a weak but significant change
      in the mean late winter circulation over Europe, which re-
  sults in detectable impacts on the near-surface climate. Fig-
   ure 9 suggests that during solar minima more cold air is ad-
  vected from the Arctic, thus resulting in a slightly increased
probability of colder winters for large parts of the continent.
 Sirocko et al. (2012) recently reached the same con-
 clusion after analyzing 140 yr in 20CR, although their results
are strongly dependent on their selection criteria for
  the solar minimum composite (van Oldenborgh et al., 2013),
    which includes only one winter for each solar cycle". 

 Analogue Sunspots

When reviewing the analogues; I look at where in the solar cycle the sun was in past relevant years and compare them to current sunspot cycle. Since this set of analogues are grouped with La Nina three year periods, the solar X's on the chart are averaged in the three year period.

Ironically; all of the analogue solar cycles during the three year La Nina cycles are at similar strengths as this La Nina years. The all averaged around 100 like this current set of three La Nina's. This three year cycle also averaged from around 75 to 130. Two solar cycles were on the way up and two were on the way down on the analogues. This current set of La Nina's solar cycle is positioned on the way up - like 1892-95 and 1998-2001. As far as the entire weaker solar wave; 1892-95, 1908-11 and 1973-76 are all similar.

 Winter 2022-23 Analogues

Temperature, precipitation and snowfall are limited, scant or obviously missing in Flint and Saginaw and those years were excluded from averages. The columns contain a M (no data) and are shaded light purple on the chart. The questionable data is entered but shaded darker purple and again, not included in calculations and averaged.



Analogue La Nina Winters - Temperatures



Analogue Third La Nina Winter - Temperatures


 Analogue La Nina Winters - Precipitation/Snowfall


Analogue Third La Nina Winter - Precipitation/Snowfall


Analogue Findings

Late Autumn-Early Winter

If anything; the data shows quite variable temperatures (a.k.a. roller-coaster pattern) especially month to month or intra-month.  However; one of the first things you notice is that many analogues are "front-end loaded" this time around. Aggressive cold snaps followed by moderation; some with notable snows in November and December. At this early junction; 1975-76 winter stands out at this time as being a potential "predictive analogue" for the winter -  given some hemispheric/local similarities thus far. But it is way to early for any "season projection'' and why we must look at all trends and patterns in the analogues.

The last 5 Decembers have been on the mild to warm side for December; I can't vouch for this one but the analogues do suggest this December; colder than average and snowy. Out of all the analogues /12/; eight Decembers averaged below normal while seven had above normal snow. As mentioned above; this would be quite a contrast to the the past several December's temperatures. Of course; patterns usually don't fit neatly into a monthly time-table. Generally the first half of the winter, December - January seemed to be the most notable.

Mid - Late Winter - Early Spring

Mid winter on is more variable; with the entire winter temperatures averaging normal to below. With the warmer climate as of late; it also is prudent to keep that in mind as the norms have risen. While snowfalls are variable; there is a drop-off mid or late winter but with a risk of a late season storm or two. Analogues do intimate the heaviest snow for the 2022-23 season to be over central and northern areas of Southeast Lower Michigan. Basically; roughly northwest of a line from the Ann Arbor area to Port Huron (or a more typical snow layout). We shall see.


Upper Air/Surface Patterns and subsequent chosen La Nina analogues; suggest normal to slightly below normal or +1.5 to -2.0 of the new 1991-2020 norms.


Upper Air/Surface Patterns and subsequent chosen La Nina analogues; suggest normal to locally above of the new 1991-2020 norms snowfalls and precipitation. 

 All Analogue La Nina 500mb Anomalies/Storm Tracks


 Analogue Third La Nina 500mb Anomalies

 Next we'll take a look at the Computer Guidance around the world for this upcoming winter

Making weather fun while we all learn,
Bill Deedler - SEMI_WeatherHistorian