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.
WeatherHistorian-SeMI: Celebrating 25 years - Retired NWS Weather Historian after 37 years, Bill Deedler, continues his thoughts and forecasts on evolving weather patterns and Season Outlooks affecting Southeast Lower Michigan.
Another Risk of Frost BUT a Nice Holiday Weekend Follows!
45 years ago Jan 26-27TH, 1978 ~ "A GREAT STORM IS UPON MICHIGAN"
THE GREAT BLIZZARD OF 1978!
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.
The Great Storm
"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."
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,
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,
The Whitest of Christmases and Other Christmases Past and Chances for a White Christmas - 2022
More Previous Christmases back to 2004:
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:
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,
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.
LATEST COMPUTER GUIDANCE ON WINTER 2022-23
BRITISH MET /UK/
MULTI MODELS (BRITISH MET /UK/, EUROPEAN /ECMWF/, DWD - GERMAN, METRO FRANCE, ITALY, NCEP, JMA - JAPAN)
Making weather fun while we all
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.
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/
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.
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
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
Quasi-Biennial Oscillation /QBO/
THE QBO INFLUENCE
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.
What is the Atlantic Multidecadal Oscillation (AMO)?
SOLAR CYCLE /SC/
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:
Sirocko et al. (2012) recently reached the same con-
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
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
Bill Deedler - SEMI_WeatherHistorian