12/27/14

So: Where's our Winter and Snow Thus Far??? Looking Back and Foward into the New Year of 2015

The cold season started out with a bang in November but then quickly went to a whimper in December, the true cold or winter month. This December has been well above average in the temperature department and has had little in the way of measurable snow. Officially in Detroit; just a trace of snow has fallen thru the 27th and it's liable to stay that way through the end of the month! It would be the second least snowfall ever recorded in Detroit since 1880 with only 1889 seeing NO snow. And, all this coming after last winter's record snowfall; I just tell people Mom Nature used up her snow allotment last winter ;-).

So, what's going on?  Well, I have a few hypotheses and a theory about that and it actually finds it's roots in my Winter Outlook when looking at the broad key players this winter.

Ok; then what am I posting about, what are the basic key players, the hypothesis's and resulting theory?

The key players or passengers as you will, in our jet stream "vehicle" since November: NAO/AO, North-Central Pacific Water Temperatures, EPO and El Nino  (in order of precedence).

NAO/AO: North Atlantic and Arctic Oscillations

Should be no question about this one, the main driver or pilot in our weather this late fall and early winter. Or is it? Is there another, while not the main driver - a "back-seat" driver?

First, note the NAO track record thus far this cold season: it's mainly encompassed in a positive phase. Also, see the NAO remains weakly positive thru most of January; but what of the AO?











Now the AO, Arctic Oscillation did show some life back in November and early December with negative phases and our temperatures in Southeast Lower Michigan acted accordingly by falling below normal. Note the decline or negative phase estimate the remainder of the winter and early spring. I wonder if that trajectory will verify?













North and Central Pacific Water Temperatures:

In my opinion or hypothesis, this and not the weak El Nino has been the co-pilot or "back-seat driver" thus far during the cold season and the "co-conspirator" (along with NAO/AO) as to why December has been mild and uneventful. The wide area of above normal temperatures across the general Pacific has been a major contributor the mild month.
In my Winter Outlook, I stated that the second area of warmer than average water temperatures stretching across the Pacific, north of the El Nino may be just as important as the up and coming El Nino. Here is my explanation and Map from the Outlook:

"It is still assumed however, that the weak El Nino will affect the cold season upper and surface wind flow by aiding and abetting the subtropical flow into the country. In addition, another item of importance is the large area of above normal water temperatures seen out in the mid Pacific north of the standard El Nino. I feel this too will also influence the sub-tropical jet, especially the late Autumn into early winter anyway (see Nov map below). By mid to late winter, the warmer waters all around the central Pacific are understandably projected to wane (Feb map). 

The below Pacific water temperatures pattern is now reminiscent of a positive PDO /PDO+/ along with the weak El Nino. Recently, negative PDO conditions have held sway out over this region. Below are the current November water temperatures including the positive PDO with warmer waters surrounding cooler waters in a horse-shoe shape".



Check out the dominant flow across that region and the U.S. this past 30 days in the boxed-in areas.





Mid November to mid December's 500H trajectory below shows very well the strong Pacific jet and also the cold polar vortex /500 Upper Low/ over eastern Canada. Both of which we've had a taste of since November...and battle is ON!




Meanwhile our third player or passenger /EPO/ has remained rather quiet this winter /Dec/ trip thus far, being mainly in a positive phase but it too seems to becoming restless.


EPO: Eastern Pacific Oscillation

Unlike last winter and main reason we were so cold last winter, the EPO has not been in a dominant negative phase. When in a negative phase, it encourages ridging along the west coast of Canada which connects with a cross polar projection of Arctic air and frequently works in conjunction with the NAO/AO but this conjunction as we saw last winter, is not always needed for a Arctic air delivery to U.S.

Note the phases of the actual observance of the EPO phase this fall and early winter on the top panel, of the EPO Index. However, more interesting developments are the change that is projected (and is actually happening as I write) on the successive 4, 7, 10 and 14 day forecast below. Check out the dates on the bottom then look again at the top panel. A strongly negative phase corresponds well with much of November, the cold month, the well below normal temperature month we just felt. See the change in the phase index in December? Nearly the whole month has been positive and that to a lesser extent, along with a positive NAO/AO and the warm waters in the Pacific; have all helped keep the bitter cold air in mainly Canada since early December.






El Nino:

The fourth "passenger" in this winters jet stream "vehicle" is of course the one everyone makes a fuss over, the boy child; El Nino. While he's been squakin and fussing some, he's terribly weak and really not even at "official" El Nino status yet.



From the Climate Prediction Center

Although the SST anomalies alone might imply weak El Niño conditions, the patterns of wind and rainfall anomalies generally do not clearly indicate a coupling of the atmosphere to the ocean. Therefore, despite movement toward El Niño from one month ago, the combined atmospheric and oceanic state remains ENSO-neutral.
 
Similar to last month, most models predict SST anomalies to be at weak El Niño levels during November-January 2014-15 and to continue above the El Niño threshold into early 2015 (Fig. 6). Assuming that El Niño fully emerges, the forecaster consensus favors a weak event. In summary, there is an approximately 65% chance of El Niño conditions during the Northern Hemisphere winter, which are expected to last into the Northern Hemisphere spring 2015 (click CPC/IRI consensus forecast for the chance of each outcome).

That is another great reason why this very mild and uneventful December is actually a "psuedo El Nino", there really isn't one but it's been like one. El Nino really hasn't had an influence on the States by most accounts, which leads me back to what I feel are the main drivers in this winter thus far: NAO/AO and the mild Pacific waters and strong jet across them.

Why Have the Models Been So Erratic (Lousy)?

So what gives for the immediate future and why have the models been all over the place with storm development and cold air delivery timing?  Well just look at what they are up against, two or three "passengers" trying to gain control over the weather pattern into the country. The "main driver" or pilot; NAO/AO is fighting against a stubborn "backseat driver" or co-pilot the Pacific Jet and mild above normal water temperatures. Yes the analogies are somewhat silly but very "apropos" given the radical and inconsistent behavior of the forecast models dealing with them.  After all, when people think about the chaos of driving and other "drivers", it is a common image yet it really does capture the multifaceted battle in the atmosphere. ;-)

Near Term Outlook

As you can tell by some of the prognostic data presented here there is a change afoot this week anyway; and when there is a change in the overall pattern that usually involves a storm and colder air. Well again the models are dancing around with possibilities of a New Years weekend storm /3rd-4th/ and again it's everything from a major snowstorm to rain or freezing rain to nothing for us. Stay Tuned! Also, after we'll look into what January is likely to have in store and compare its past - analogues - with this December and into January.

New Years Eve looks good weather-wise right now with only the drinkers and subsequent drivers to be concerned about!

Have a Happy, Healthy and Prosperous New Year for 2015!

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

12/21/14

Ghost of Christmases Past; The Whitest of Christmases and Other Christmases Past

The Whitest of Christmases and Other Christmases Past 
 
By: William R Deedler; Southeast Michigan Weather Historian
Date: 7AM Sunday Dec 21st, 2014
 

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, but not necessarily have to fall on Christmas. 

At this time /21st/, we have the likelihood of a storm but just a slight chance of a white Christmas across all of Southeast Lower Michigan from any residual snowfall late Christmas Eve into Christmas.  Over the years extreme Southeast Lower Michigan has average about 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 is falls on the day.  Now officially there must be an inch of snow on the ground Christmas MORNING at 7am. That is how the official "white Christmases" have been tallied n the past. So 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 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.

Timing isn't the issue this year it's more technical than that; while precipitation is likely before and maybe on Christmas - how much of it falls as snow /need an inch/ is the big question. As of the 21st, it looks like most of the precipitation will be rain before Christmas and maybe just snow showers  Christmas Eve and Day. Also, like many years before,  it may depend where you are in Southeast Lower Michigan as to whether or not you will enjoy a white Christmas this year (similar to last year). 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.

Previous recent Christmases
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 114 (including 1900) Christmases in Detroit, 54 (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.

Based on the Detroit records, the Santa award for the "whitest" (most snow on the ground) and also the second snowiest Christmas (snow falling on Christmas) goes to the Christmas of 1951! Just over a foot /13 inches/ of snow was recorded on ground late Christmas day with 6.2 inches of the snow falling on Christmas. Temperatures held well below freezing (HI-26/LOW-18), so what snow did fall, remained. A close second to the "whitest" Christmas, occurred the Christmas after the big stock market crash in 1929. Eleven and a half inches of snow was measured December 25th, 1929 at Detroit but only three tenths /.3/ fell on Christmas. 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 2015! 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

12/15/14

Update-12/24/14>>>Extended Models Intimating Notable Pattern Change Christmas Week - HO HO HO?

12/24/14-Update 230p
Very little change from earlier thinking, any residual moisture behind this system will fall as rain and snow showers. Temperatures will be contrary to any snow accumulations except possibly in the Saginaw Valley where moisture will be last to leave and temperatures first to fall. Any light accumulations would be on grassy areas in that area and mainly an inch or less. Overnight lows will fall into the 30s to around 40 and hover in that range Christmas Day.

Latest Indications Point To a Wet Christmas Eve & Light Snow and Snow Showers For Christmas Day  

A reasonable pattern evolution of the Christmas week storm is unfolding for the Great Lakes and Southeast Lower Michigan. The storm development previously blogged below, remains intact while the Great Lakes tract depicted as one of the possibilities, the most likely winner. 

Jet structure and max winds depict a large negatively tilted trough developing over the region on the 23rd into the 24th, Christmas Eve. At the surface, a deep cyclone will develop along a slow moving - quasi stationary cold front extending from the Gulf States northward into Lower Michigan during the day on Christmas Eve. This deepening storm center will pull substantial moisture and moderate warmth northward into the Great Lakes and Southeast Lower Michigan in the form of rain on the 24th and then light snow and snow showers Christmas Day. With any luck, we'll see enough snow showers on Christmas for a "snow in the air" Christmas but I wouldn't count on an official "white Christmas" this year - at least as things look now. I wish I could be more hopeful for a white Christmas but possibly enough moisture will remain behind the system in the seasonably colder air to generate the inch needed /per GFS/, so will update as the time rolls on closer. Speaking of "White Christmas" look for my annual "Ghost of Christmases Past; The Whitest of Christmases and Other Christmases Past, shortly. 

Surface Maps Particulars

Note the European is faster and further north with the low over Lower Michigan by Christmas Eve 7AM, whereas the GFS brings the center into the region by Christmas Eve 7PM.




Then by Christmas morning on Thursday, the Euro has the center of the storm
well up into Canada where as the GFS holds more moisture and energy aloft along with the surface reflection over the Great Lakes and thus, a better chance for light snow and snowshowers.




Look for a further update early this week.
  
Merry Christmas & A Happy and Healthy New Year
_______________________________________________________________________

12/15/14 - Initial Post

Meteorologists and Weather Enthusiasts have seen it before, too many times to count in extended model la la land, an overhaul or notable change of the prevailing pattern being suggested a week to 10 days out. This time, the pattern change is rather strongly intimated by the GFS and European model right around Christmas - or at least Christmas week /22nd-28th/. Each day something new and different pops up; a snowstorm for the East Coast, the Midwest or the Ohio Valley and Great Lakes followed by a sharp cold blast in its wake. The only thing for "certain" is that an overall Jet Stream pattern change will evolve sometime the latter part of December and that will likely create a mess for someone (more further below) around the holiday.

Autumn into Early Winter 

No one has to be told it's been a rather tranquil and boring beginning of the meteorological winter /Dec-Feb/ and this coming after a rip-snortin' unusually cold, blustery and busy November (which had its deep cold roots in place by Halloween time). Looking back, the pattern this fall into early winter was well projected by upper air and surface patterns of the past with similar hemispheric traits in the Autumn Outlook.

Fall is cited for its wild swings in temperatures and this fall certainly should be no different as impressive upper lows in Canada dive south and southeast into the U.S. The aggressiveness of this overall, now common-place pattern shows little change in the last year. Both upper air and analogues also do suggest typical to strong cold outbreaks along with some contrasting upper ridging to bring classic Indian Summer weather.

Oscillations of upper and related surface patterns with a preference toward troughing and cooler than normal weather should be balanced out somewhat, leaving us with an average or normal fall with notable sharply contrasting patterns. I look for temperatures to average around normal...or within two degrees of the normal. 

As it turned out; temperatures this past autumn did fall well within the projected spread of the selected analogues and Outlook across Southeast Lower Michigan averaging exactly a degree /-1.0/ below normal at 49.8 /norm 50.8/. September and October averaged near to slightly above normal where as our cold November, averaged well below normal.

This "now suitable, now brutal" kind of weather regime was projected to persist into the winter with strongly oscillating weather patterns resulting in cold, mild, stormy and tranquil kind of winter. I bring this all up because as you know; recently we've had a few weeks of the rather tranquil weather to start off December and the winter thus far - BUT there is a change afoot!

 

Back to the present and future...

Many meteorological indicators are pointing to a colder and stormy pattern with this change, certainly not uncommon and pretty much expected. It's the questions of where (and thus who), what and when that have to be answered.  The NAO and AO both are pointing to radical hemispheric change later in the month while the PNA remains weakly positive (or suggests troughing east of the Rockies). Both the NAO and especially AO are rather extreme with their collapse into negative territory (likelihood of colder weather). There still are variances in the overall decline from positive to negative and thus, problems in forecasting are strongly affected.

 

 

 

It is easy to see as both oscillations advanced into their positive phases beginning in December, the month became more tranquil and progressively milder over Southeast Lower Michigan, the Great Lakes and East. And generally, when there is a notable change like this projected there is a storm-a-brewin for someone and some part of the country. Here's some scenarios spit out by the GFS & European models for Christmas time.

 

Dec 15th 00z GFS, Snowstorm for the Eastern Lakes Christmas Eve 12/24>>>

 

This morning's, Dec 15th 12z GFS run (note the storm is again over the Eastern Lakes but it's now Friday morning 12/26)


 

The Dec 15th 12z Euro has a different view, she puts most of her eggs in a Northwestern Lakes Low Christmas Eve Day with a second forming just west of the Appalachians but as you can see (second map below), it undoubtedly makes headway toward the Northeast Coast just in time for Christmas

 

 

Of course, there is a lot of time between now and Christmas week and thus, numerous scenarios will be created in model la la land. In the meantime, it would be prudent to keep abreast of this change in the weather projections since it is definitely a heavily traveled time.

 

As the time gets closer I'll look at what's the most likely scenario - and where and when.

 

Merry Christmas & A Happy and Healthy New Year

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

12/3/14

40TH Anniversary of Detroit's Highest Snowfall in Modern Times!

This week marks the 40th anniversary of Detroit's biggest snowfall in amounts in modern times; December 1st, 1974 - including surface maps. The biggest snowfall of all time was way back on April 6th, 1886. Back in 2000; I wrote what I called "A Tale of Two Storms" which paralleled the two biggest snowstorms (in amount) to ever hit Metro Detroit. The second storm in the article, I will never forget as I worked it during my first year as a novice with the NWS. To this day, I have yet to see a storm quite like it; as far as the magnitude it snowed and for such a long period of time! Enjoy!  Here are reviews of both storms:

THE TALE OF TWO STORMS
By: William R Deedler, Southeast Michigan Weather Historian

Initially, I had intended to write about Detroit's biggest snowstorm ever recorded (24.5") but while researching the storm (which occurred way back on April 6th, 1886), I was struck by the uncanny similarities between that storm and Detroit's second biggest snowstorm (19.3") which occurred nearly a century later on December 1st, 1974. Besides the obvious similar snowfall amount between the two systems, other significant parallels could also be drawn. In addition,  while I was obviously not around to observe the first huge storm, I did have the opportunity to witness the second first-hand, in my earliest days with the National Weather Service. Unfortunately, weather maps for the1886 storm are unavailable, unlike the 1974 storm (below). With the aid of surface observations and weather journals however, at least an estimate of the surface and upper air data can be made. Perusing through the carefully scrolled weather journals of the late 1800's, one can't help but be amazed and "taken back" by the simplistic, yet stylish way of which they were written. In addition to hourly weather observations and climatic statistics, each day contains usually a short synopsis of the weather experienced for that day. It is the weather logs from late on April 5th - April 7th, 1886 that really commands ones attention and awe.
 
APRIL 1886 -
By early April 1886, some residents of Southeast Lower Michigan had most likely started on spring outdoor activities. High temperatures frequently pushed well into the 50s from mid March on; the last hint of snow fell nearly two weeks before on the 23rd. No doubt the growing season's new green vegetation was well underway.
 
The weather days proceeding the massive and incredible snowstorm hinted little of what was yet to come; however, there were some subtle signs of trouble brewing. The first was a fresh, brisk northeast wind that blew continuously for nearly three days prior to 6th (generally, an easterly wind along with a falling barometer in this region, foretells of foul weather approaching the area). On the 4th into the 5th, observations including temperatures, wind flow and pressure changes indicated an unseasonably cold high pressure system pushing slowly into Southern Canada and the Northern Great Lakes. This persistent and strengthening northeast wind along with an extended period of steady, then slowly falling barometric pressure, during the three-day period (3rd, 4th and 5th), indicates this high was a fairly strong, resilient and a blocking type of high pressure. A second and more foreboding sign of what was to come was indeed a rapidly falling barometric pressure later on the 5th, which foretold of the major storm approaching Southeast Lower Michigan. The surface observations late on the 5th indicated a low pressure and storm center approaching the Southern Great Lakes from the south or southwest (most likely from Illinois, Indiana or Ohio) as the cold high to the north slowly retreated.
 
The afternoon high on the 5th reached only 38 degrees (about 15 degrees below normal) and then held nearly steady into the evening. Increasing high cirrostratus clouds mingled with the sunset but then, quickly lowered to altostratus and nimbostratus as midnight approached. Light snow began to fly just after midnight and remained light until becoming heavy during the predawn hours. Note the following taken from the actual Detroit Weather Log dated April 6th, 1886:
"Snow began at 12:30 AM and fell light until about 4:30 AM when it began to fall heavy and a tremendous fall of snow continued all day, ending at 9:00 PM. The fall at 7:00 AM was 4.6" and at 3:00 PM was 17.1" and at 11:00 PM, 2.4" making the total of 24.1 inches melted from the snow gauge. The rain gauge was soon snowed full and was practically useless. Total fall of the snow on the level was 24.5 inches. The snow was badly drifted by the heavy gale. The drifts in some places were 12 feet high and the snow in the street was from 10" to 40" inches deep. A heavy north gale set in at 1:45 AM and raged in fury all day reaching 40 miles north at 2:15 PM and continued all the remainder of the day. Its force with the snow was appalling. It blew the snow in fine particles against the face, cutting like a knife."
The synopsis continues with a description of numerous street cars that were abandoned, strewn about and laying in all sorts of positions. As one might expect with the snow falling in April, the snow contained a high water content (2.43") and, therefore, it was very heavy and packed down well. Obviously, wading through the snow to get around on foot was extremely difficult - so much so that it became necessary to use crowbars and ice picks just to clean a path on the street. Maneuvering through, or just moving the snow, was such a monumental chore that even several ton railroad cars were "held prisoner in their houses". On the train tracks, freight cars were immobilized and abandoned across all of Southeast Lower Michigan. Temperatures held in the upper 20s to around 30 through the entire snowfall, with over two feet of snow reported on the ground. The strong northeast to north gale sculptured towering drifts of snow up to 12 feet high across the landscape .The howling wind averaged over 30 mph during the 24 hour period. The lowest barometric pressure reading noted was 29.60 inches at 11:00 AM on the 6th. This reading isn't too terribly deep or severe (the lowest pressure ever observed in Detroit was 28.34 inches during the late January blizzard of 1978), but the pressure was taken only five times daily (7:00 AM, 11:00 AM, 3:00 PM, 7:00 PM and 11:00 PM), so it likely fell lower As the center of the low pressure drifted further north into the Great Lakes on the 7th, milder air from the south was drawn into Southeast Lower Michigan. The sky cleared as the wind shifted to the south and the temperature rose to 40 degrees, in spite of the very heavy snow cover. In the days following the storm, temperatures managed to push up well into the 50s and even reached the mid 70s by mid month, after all, this was April, right?
 
This storm stands as Detroit's biggest and severest snowstorm and is well summarized by the following quote in the journal and actually would still stand to this day. . .
"The storm was unprecedented in fierceness, snowfall and blockades in the history of the service and the oldest inhabitants can recall nothing to equal it".
DECEMBER 1974 -
It would be nearly a century later before a very similar storm, a sort of "meteorological clone" would arrive and again leave the region snowbound with the second highest snowfall (19.3" as compared to 24.5") ever recorded in metropolitan Detroit in a single storm. While there were several similarities between the two storms, one obvious difference was their timing in the snow season. Also, it is interesting to note here, that neither storm occurred during what is officially called "winter." While the 1974 storm occurred in late fall at the forefront of the 1974-75 winter season, the April 1886 storm showed up on the doorstep of spring.

Besides the similar heavy snowfall between the storms, there is the likeness of the surface observations taken before and during each storm. As its predecessor, the 1974 storm was proceeded by a few days of persistent northeast winds along with an initially rising barometric pressure, then after, an extended period of steady pressure readings before giving way, slowly at first, to falling pressure. Also, like the 1886 storm, temperatures crept up into the mid to upper 30s on both the 29th and 30th (though these highs were not anywhere near as below normal as in the April 1886 storm). On the 30th, the northeast wind averaged around 19 mph with peak gusts close to 30 mph. The persistent strong northeast wind with just a slow climb in daytime temperature was a result of a large stationary polar ridge axis of high pressure that extended in a horseshoe shape (an Omega High) from the Great Plains, north into the Dakotas, then east across Lake Superior into Quebec, Canada and finally south along the East Coast. The high's strength and position also recalls that of the1886's high pressure mentioned previously.
The development and track of this super snowstorm was complicated and quite a hassle for forecasters that Thanksgiving weekend. The primitive forecast models (when compared to the more sophisticated and better resolution of today's models) had quite a time in predicting the track of the storm and its intensity. Even up to the day of the storm, the forecast models continued to weaken the center of the storm as it moved into Kentucky and Ohio, while intensifying a new storm along the East coast. On Saturday, November 30th, a strong closed-off 500 MB Low advanced into the Mid-Mississippi Valley, while at the same time, at the surface, an inverted trough of low pressure extended from a low over the northern Gulf of Mexico, north northwest to a second low over Missouri. The consensus of the forecast models was to bring the 500 MB and surface low generally east, into the Ohio Valley and weakening both. In the meantime, the Gulf Low was forecast to track north northeast up the East Coast and intensify; thus, becoming the main low and storm center of the entire system. This was the accepted forecast scenario with the data available at the time and could hardly be argued otherwise. Actually, this predicted path and subsequent weakening of the Ohio Valley low as the East Coast storm intensifies or "bombs-out" is what generally happens. The models failed in forecasting the weakening trend of the Ohio Valley system. The 500 MB Low and the surface low not only did not weaken, they actually intensified and became vertically stacked in the atmosphere. Generally, when this happens the system tends to hold on to its intensity longer and slow down in movement, both of which proved detrimental to the computer forecast.
 
Light snow moved into extreme Southeast Lower Michigan during the predawn hours between 5:00 AM and 7:00 AM. Even at the 5:00 AM forecast issuance, it looked as if just one to three inches of snow would blanket extreme Southeast Lower Michigan for this event. However, by sunrise, already up to three inches of snow covered the region and the snow was not getting any lighter. A stiff northeaster' also accompanied this storm, though not as severely as the 1886 storm, averaging 20 to 30 mph with gusts above 30 mph. By sunrise, an area of snow had settled over extreme Southeast Lower Michigan. On radar during the forenoon hours, bands of heavier snow appeared over Northern Ohio and Lake Erie, trekking west-northwest toward Michigan. By now, the forecasters knew the forecast was in trouble and updated the forecast to read "six or more" inches of snow.

The 500 MB Low and associated energy to support the surface system drifted east over Kentucky, while the surface low that was over Missouri drifted east right along with it. A huge conveyor belt of moisture had set up in the atmosphere extending from the Gulf of Mexico and the Western Atlantic, east into the Ohio Valley and Southern Great Lakes. Not only had the storm tapped the usual Gulf moisture; now Atlantic moisture started to be drawn into the mix. After analyzing surface data from the 1886 storm, it is strongly suspected that this too was the case at that time. Huge moisture plumes from both the Atlantic and Gulf of Mexico fed the1974 storm and likely, the1886 storm, with nearly duplicate surface observations before and during the event.

Bands of snow (much of it moderate to heavy) continued to be produced across the Eastern Great Lake States on the "conveyor-belt" through the afternoon, with the heaviest snow falling across extreme Southern Ontario, extreme Southeast Lower Michigan and extreme Northwest Ohio. By mid afternoon, already between six and ten inches of snow was on ground across much of extreme Southeast Lower Michigan, with generally eight to ten inches in the metro Detroit area. Visibilities were frequently near zero and moderate northeast winds blew the heavy, wet snow into at least three to five foot drifts. Another notable item observed during the storm was frequency of large snow flakes. Generally in the majority of snowstorms there may be a period or two of heavy snow with large flakes and a quick accumulation of snow. During this storm however, there were several periods, or waves, of heavy snow with continuous large flakes and very low visibilities, migrating in from the east over the region.



 
The surface low drifted north northeast from Kentucky into West Virginia by Sunday evening on the 1st and gradually matured and occluded. It still remained however, the dominant low (which was not forecasted by the forecast models), while the second low on east coast moved north at the triple point (at the point where the occluded, warm and cold front of the system met) and never really developed. As darkness fell, generally up to a foot and a half of snow smothered the metro Detroit area, with six to twelve inches elsewhere in extreme Southeast Lower Michigan. During the evening the snowfall became lighter and by midnight, 18.4" was officially observed at Detroit Metro Airport. Another nine tenths of an inch fell early on the 2nd, for a grand total of 19.3" (19.2" of it falling in 24 hours) with Flint reporting a snowstorm total of 8.1". As the low drifted northward, milder air filtered into the region and the snow became mixed with, and then changed to drizzle.

Coincidentally, the next day (Monday, December 2nd, 1974), the temperature also warmed to 40 degrees in the afternoon, but the wind remained more northerly rather that shifting to the south (as on April 7th, 1886). This was due to the fact that the center of the low tracked further east of Southeast Lower Michigan into Pennsylvania, rather than into the suspected Great Lakes area in 1886.
 
Some other accounts of the storm:





http://www.annarbor.com/news/top-10-storm-snowfall-totals-for-the-ann-arbor-area/

http://www.theoaklandpress.com/general-news/20130208/10-worst-snowstorms-in-metro-detroit-history

http://www.toledohistorybox.com/2010/12/01/snowstorm-buries-toledo-december-1-1974/


From a reader -

Attn: Bill Deedler re: snowstorm Dec 1, 1974

Sir, I remember that storm well: I was visiting a friend in Kalamazoo. She watched the fledgling Weather Channel early in the morning when she awoke to lightly falling snow. She told me to leave early because the snow would fall first there. Little did I know that the farther east I drove back to Ann Arbor, the snow would get worse and worse. A normal trip of maybe 2 hours turned into 5 hours. It took me an hour to exit I-94 up the State Street exit, at times pushing my car myself. When I finally arrived at my apartment, I got stuck outside. I left it there. Cold, wet, tired, frustrated and alone, I got a phone call from a friend whose parents took him back to U of M early that morning. He walked 3 miles in 18 inches of blowing snow to comfort me. I married that man and am still happily married to him to this day. I will never forget December 1st!!

Sincerely, Judi -  Allen Park, MI
Any other accounts, I can publish in Comments section below.

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

11/16/14

Is It Cold Enough Yet?? Eh, Mom Nature's Just Gettin' Started; Now For Round 2 & 3...

Last week, I warned of the unseasonably cold air projected in our extended guidance to slam the region. "The polar plunge is slated to push into Southeast Lower Michigan by Tuesday night and then, hang around to get reinforcements into the following week (11/16-22)"!

Well hang on because those cold reinforcements are yet to come for Southeast Lower Michigan. They, basically will come down in two cold waves; the first (and the worst) will arrive during Monday, while the second comes down later Wednesday, just to "seal the deal". Gusty winds with bone chilling wind chills down as low as zero or below will accompany snow showers and squalls to complete the 5 week before winter scenario. Looks for temperatures to range from mainly the 20s for highs and teens and even some single figures for lows, during the coldest time in the up coming week. Normals this week; mid to upper 40s for highs and lower 30s for lows. So several days we won't crack the normal lows! In fact, some days this week won't match the normals for the coldest winter days in later January!

Ironically (as mentioned in my last blog, below), we should be engulfed in the throws of the Arctic regime around the same time as the incredible cold wave of 1880!  A welcome moderation, finally should commence this next weekend /22nd-23rd/ and beyond (at least for awhile) so those records for next weekend /22, 23/ look more than safe.

"It will be interesting to see if we can challenge the resilient stretch of record low temperatures for mid November that I wrote about here, previously as SE_Mich Weather Historian (and earlier with the NWS). This record cold stretch occurred /1880/ way back near the dawn /1874/ of official records at Detroit and still hold up till this day! Both the intensity of the cold that we experience and timing may be an issue, we'll see. Something to keep in mind, especially if we have snow on the ground at the time".

DETROIT - NOVEMBER RECORD LOW MAXS AND LOWS IN BLUE
18 48 34 41.0 69/1941 18/1880 55/1954 11/1880 60/1954 14/1880 0.97/1929 18
19 47 33 40.0 68/1985 22/1880 58/1985 9/1880 63/1985 16/1880 1.07/1948 19
20 47 33 40.0 70/1942 23/1895 57/1913 12/1880 60/1931 19/1880 1.02/1988 20
21 46 33 39.0 67/1913 12/1880 56/1931 3/1880 61/1931 8/1880 1.16/2007 21
22 46 32 39.0 69/1913 16/1880 57/2010 0/1880 62/1913 8/1880 2.59/1909 22
23 45 32 38.0 69/1931 21/1880 57/1931 8/1880 63/1931 14/1880 1.24/1891 23

Now while it remains to be seen if we can break any of those archaic records at Detroit from 1880. Flint and Saginaw may be another story, as their records don't include the brutal cold of 1880 for November and little, if any heat island affects those sites. Still, they both have some decent standings in the cold record department this week and several may be a tough "ice-cube" to crack....

FLINT - NOVEMBER RECORD LOW MAXS AND LOWS IN BLUE
18 46 30 38.0 68/1975 25/1989 52/1971 11/1959 59/1971 19/1989 1.03/2003 18
19 45 30 38.0 70/1953 28/1927 58/1985 13/1986 63/1985 22/1927 1.20/1921 19
20 45 30 37.0 68/1953 25/1969 56/1942 14/1969 61/1934 20/1969 1.40/1942 20
21 44 29 37.0 66/1931 24/1964 55/1934 7/1969 60/1934 17/1969 0.65/2007 21
22 44 29 36.0 65/1934 23/1929 57/2010 9/1929 61/1934 16/1929 1.02/1992 22
23 43 29 36.0 68/1931 25/1956 54/2003 10/1956 60/2003 18/1956 0.61/1983 23

SAGINAW - NOVEMBER RECORD LOW MAXS AND LOWS IN BLUE
18 45 31 38.0 68/1975 24/1989 52/1971 11/1989 60/1971 0/1998 1.30/2003 18
19 44 30 37.0 72/1953 29/1951 56/1985 11/1914 61/1991 0/1998 1.16/1913 19
20 44 30 37.0 69/1931 25/1914 52/1982 11/1914 58/1931 0/1998 0.85/1942 20
21 43 30 36.0 69/1913 25/1964 55/1934 10/1969 62/1913 0/1998 0.60/1979 21
22 43 29 36.0 66/1913 23/1929 55/2010 11/1929 58/2010 0/1998 1.70/2010 22
23 42 29 36.0 72/1931 25/1917 56/1931 7/1950 64/1931 0/1998 1.06/1983 2

It will largely depend on the cloud cover and snow cover. While this air certainly has the potential for record cold, I would be remiss if I didn't mention the importance of cloud cover, snow cover AND perhaps the most important; the overall moderating affects on the Arctic air mass - the Great Lakes. Still with the right conditions...

Here are the villains in the piece this week....



* Latest Euro's Polar Vortex prog below; 11/18/12z
That's incredible to have such a low height/cold Polar Vortex over the northern Lakes in   MID NOVEMBER! Got to be a record in upper air data if she verifies...

  
Keep you and the pets warm.


Next Up - What's the big travel day Wednesday along with Thanksgiving/Thanksgiving weekend look like?


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

11/9/14

Polar Surge Heading for the Region Impressive for November Standards!

I will say; it's been awhile since I've seen the likes of the upcoming cold projected by our models for November (both in intensity and extent) for several days now. First of all, "some 3 - 4 standard deviations below normal" when speaking of the depth of the trough - from WPC. Then today again from WPC - "Well-advertized cold snap will lead the medium range period next week (week coming up) as strong ridging /500MB standard anomaly nearing +4 - which is VERY rare/. Here, the "Italian" gent (I assume) Mr. Fracasso is referring to the giant "ridge or hill" developing off and over the west coasts of the US and Canada and well into Alaska. This, ridge in turn, will grab and help plunge the polar air that two polar vortex's (one, over Siberia/Russian and the other over eastern Canada) have pinwheeling between them in a very cold conveyor-belt more reminiscent of January! Take a look>>>




And the map above is a week from now (11/9) which brings up the third notable item about this cold wave - it's endurance! The polar plunge is slated to push into Southeast Lower Michigan by Tuesday night (below) and then, hang around to get reinforcements into the following week (11/16-22)!



Two other things come to my mind this early on; One- I'll be damn surprised if we don't place in or near the top 10 coldest Novembers - barring any extreme warm-up the last week. The last time we placed in the top 20 record coldest November's list was back 1997, in the 20th position with 37.1 degrees. A colder and much better placement occurred just the year before in 1996 with a 34.2 - which placed 3rd! Ironically, the year before that /1995/ we again placed in coldest Novembers list, with 35.5 degrees - 9th spot.

Rank Detroit Area* Flint Bishop** Saginaw Area***
Coldest Warmest Coldest Warmest Coldest Warmest
Temp Year Temp Year Temp Year Temp Year Temp Year Temp Year
1 29.8 1880 47.8 1931 31.3 1951 47.3 1975 29.8 1951 47.2 1931
2 33.5 1976 47.6 2001 32.0 1995 46.6 2001 31.6 1995 45.9 1975
3 34.2 1996 46.9 1902 32.6 1996 46.2 1931 32.5 1959 45.5 1902
4 34.5 1875 46.8 1975 33.0 1959 44.4 1934 33.3 1976 45.3 2001
5 34.6 1951 46.6 2011 33.3 1976 43.8 1938 33.6 1933 43.5 1909
6 34.9 1894 46.0 1963 34.3 1936 43.7 2011 33.9 1996 43.2 2009
7 35.2 1967 45.7 1948 34.4 1933 43.3 1963 33.9 1955 43.1 2011
8 35.4 1936 45.5 1994 34.8 1967 43.2 1948 34.2 1989 43.0 1963
9 35.5 1995 45.3 2009 34.8 1955 42.8 1999 34.2 1967 42.4 1999
10 35.5 1911 45.2 1999 35.0 1947 42.5 2003 34.2 1950 42.4 1948


Two - It will be interesting to see if we can challenge the resilient stretch of record low temperatures for mid November that I wrote about here, previously as SE_Mich Weather Historian (and earlier with the NWS). This record cold stretch occurred /1880/ way back near the dawn /1874/ of official records at Detroit and still hold up till this day! Both the intensity of the cold that we experience and timing may be an issue, we'll see. Something to keep in mind, especially if we have snow on the ground at the time. By the way, the last time we had a record low temperature in November is back in 1991 - and we had four during that cold snap.


DETROIT - NOVEMBER RECORD LOW MAXS AND LOWS IN BLUE
18 48 34 41.0 69/1941 18/1880 55/1954 11/1880 60/1954 14/1880 0.97/1929 18
19 47 33 40.0 68/1985 22/1880 58/1985 9/1880 63/1985 16/1880 1.07/1948 19
20 47 33 40.0 70/1942 23/1895 57/1913 12/1880 60/1931 19/1880 1.02/1988 20
21 46 33 39.0 67/1913 12/1880 56/1931 3/1880 61/1931 8/1880 1.16/2007 21
22 46 32 39.0 69/1913 16/1880 57/2010 0/1880 62/1913 8/1880 2.59/1909 22
23 45 32 38.0 69/1931 21/1880 57/1931 8/1880 63/1931 14/1880 1.24/1891 23

Again, if you'd like to read about the November 1880 stretch of record cold, click here.

And if you missed the upcoming winter's outlook, click here.

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