Wintery Mixed Precipitation to Accompany Warm Air Advection Wednesday

Epilogue:
System behaved itself with generally light amounts of snow and sleet reported over northern areas of Southeast Lower Michigan; and a bit of snow with more sleet and freezing rain central and southern areas. Most of the freezing rain was over central areas of the region with ice totals remaining below a 1/4".

http://forecast.weather.gov/product.php?site=DTX&issuedby=DTX&product=LSR&format=CI&version=2&glossary=0

http://forecast.weather.gov/product.php?site=DTX&issuedby=DTX&product=LSR&format=CI&version=1&glossary=0

blog:

At this time, it looks as though central and northern Southeast Lower Michigan...or a line roughly from north of Ann Arbor into Detroit's northern suburbs and areas northward...could see the longest period of mixed precipitation before the changeover. While light amounts of snow, sleet and freezing rain are expected, the sleet and freezing rain will be most problematic with ice amounts less than 1/4" in freezing rain areas. 

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Initial blog below:

Look for weather conditions to deteriorate after midnight during the early morning hours of Wednesday /29th/ as strong warm air advection aloft pushes into Southern Lower Michigan. This increasingly moisture-laden warmer air will trigger snow, then sleet and freezing rain as it rides over the colder air at and just above the ground. The storm center bringing the snow, sleet and freezing rain will move west of the region over southern Minnesota but will act as a pin-wheel; advecting the warmer, moist air into the region from the south. Blizzard conditions are expected out over the Upper Midwest with heavy snow into the Northern Lakes with this storm.

Much of the mixed precipitation should fall from the early morning hours into the forenoon hours of Wednesday as it moves in from the south and works its was north. The mixed precipitation will change to light rain, drizzle with just cloudy conditions thereafter in the afternoon.  In addition, a moderate east to southeast wind will accompany the event. While there will be strong warmer air riding aloft; indications are the colder air near the surface will begrudgingly give way over portions of Southeast Lower Michigan. At this time, it looks as though central and northern Southeast Lower Michigan...or a line roughly from north of Ann Arbor into Detroit's northern suburbs and areas northward...could see the longest period of mixed precipitation before the changeover. While light amounts of snow, sleet and freezing rain are expected, the sleet and freezing rain will be most problematic with ice amounts less than 1/4" in freezing rain areas. However; this is subject to change if more moisture works in or change-over is delayed.

A sharp temperature-gradient will form over Southeast Lower Michigan on Wednesday with readings rising into at least the 40s behind the surface warm front, while hovering in the lower to mid 30s ahead of it. Look for the warmer air to overtake the entire region during the after as readings rise into the 40s, to around 50 in the south. Then; look for colder air and snow showers to move back into the region Wednesday night.

Motorists be advised driving conditions will deteriorate rapidly as the mixed precipitation encompasses Southeast Lower Michigan during the early morning hours while temperatures are at/or below freezing.

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

Review of Winter Storm: February 23-24th, 2012

Epilogue 2/23-2/24/12 Storm:

Thursday 2/23 model runs on the system pivoted the storm further south than my initial projection across Northern Indiana and Northern Ohio.  In accordance; I raised snowfalls to 4" - 8" rather than the 2"- 4" with pockets of 3" - 6" forecast a day earlier on Wednesday. In retrospect, the low tracked closer to my original thinking; south of Tuesday's model projections over Illinois/Indiana but wound up further north of Thursday's model projections, over the corner of Southeast Lower Michigan early Friday. Just as important however, was the track of the upper air support which /vorticity max/ which tracked right across Southeast Lower Michigan. This was northwest of the surface low and provided maximum lift and dynamics for the system. Heaviest snow generally falls to the left (or north-northwest) of the vorticity center which was across Saginaw Valley into the Thumb (where 3" - 5" of snow with maximum pockets of 6" was observed). Heavier amounts were observed further northwest into central and northern Michigan.             
                                                      Snowfall Amounts & Map from DTX

What was learned in this event?

Just because they are the latest model runs (versions); doesn't mean they are the most accurate. Sometimes your earlier and initial analysis on a snow forecast is the better one and you must have faith to stick with it; even in the face of "model contrariness". On that premise, I failed by changing my original snowfall amounts Thursday. On the positive: I alerted the public of a storm that would impact Southeast Lower Michigan and the Great Lakes days ahead of the storm. The storm did develop and affected residents of Southeast Lower Michigan; in a winter that has been virtually "stormless"; see initial 2/21/12 blog below. 
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Blog: 2/23
Latest indications continue to show the winter storm first written about here on Tuesday will indeed affect all of Southeast Lower Michigan as she tracks eastward and then northeastward through the Northern Ohio Valley. Nearly all the models now paint an intensifying cyclone, shifting from southern Indiana northeast through central Ohio and then toward the Cleveland area by Friday afternoon. This more southerly track is in accord with earlier thinking and then some with the track now proficient for the likelihood of heavy snow across much of Southeast Lower Michigan.

While the track will be south of Southeast Lower Michigan, enough warm air will be drawn up ahead of the system to bring rain or rain mixed with snow up into the region toward sunset across the far south and this will move northeast;  encompassing all of Southeast Lower Michigan during the evening hours. Much of Southeast Lower Michigan should receive 4" to 8" of snow with this system with the highest amounts likely north of I-94. Heaviest snow inducing lower visibilities should occur toward the midnight hour and continue through the early morning hours.

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Earlier blog 2/22/12 of model and my positions:

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Initial Blog: 2/21

Latest model trends are converging on an intensifying Eastern Great Lakes low pressure system late Thursday into Friday. This system will be brought about as strong Pacific energy aloft aligns with/and phases with Polar energy diving in from central Canada.

On to the particulars; Strong energy aloft at varying levels is projected to dive east southeast from the Pacific into the Midwest by late Thursday. At the 250 MB /35,000 Ft/, the core wind max is expected to be at least around 130 knots! This upper level energy will proceed generally east and align itself along a potent stationary frontal boundary that will form and extend from the southern Great Lakes east into Pennsylvania and then, off the East Coast. At this time it looks a though a few waves of low pressure will be induced along the front while rippling east with time. As this scenario becomes more established across the southern Great Lakes and northern Ohio Valley; additional moisture will be drawn northward from the Ohio Valley and then subsequently, westward from the Atlantic. This moisture, in conjunction with the strong upper level dynamics and surface boundary, will be aiding and a betting with the development of the main Eastern Great Lakes cyclone or low pressure system by Friday. How quickly this above scenario takes place will have a lot to do with the final outcome of the weather to affect Southeast Lower Michigan.

On the projected 7 pm Thursday weather maps below; 

Map 1 from the GFS model denotes the 250 MB wind jet at 35,000 feet and speeds. The first jet core /1/ will help with the initial development of our frontal boundary and low pressure system as phasing commences; while the second jet core /2/ comes in from the rear to deepen and intensify the system during the day Friday. The second GFS map places the main developing low pressure near the tri-state area of Michigan-Indiana-Ohio also at 7pm Thursday. I feel the GFS may be too far north with the main surface low and its track could be further to the south; over the northern half of Indiana and Ohio rather than the border area.

                                                                          Map - 1

                                                                              Map - 2

Of course, this a projection of a few days out and therefore will be attentively watched and analyzed as updates from various models zero in on this system. Not only do the usual problematic winter storm specifics apply here; such as track and available moisture but also the temperatures in the lower levels of the atmosphere and surface which will dictate initially the amount of rain and snow and later, potential snow accumulation. At this time is does look as though the worst of the system will be east of Southeast Lower Michigan but it still bears watching, so stay tuned.

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

Another Arctic Air Pest To Visit For The Weekend / Epilogue-2-11-12/

The Forecast:

"The very latest indications are enough moisture will be transported into Southeast Michigan as a weak wave of low pressure transverses the front (see second map) to bring 1 to possibly 3 inches of snow across the region. Gusty north winds and falling temperatures later on Friday will exacerbate driving problems. Motorists driving Friday up through Michigan should be prepared for this winter weather and any subsequent lake effect snows with higher amounts."

Epilogue: System was a bit of a overachiever as she wound up in the eastern lakes feeding on the better moisture as the Arctic cold wrung out the moisture. Generally; a one notch higher 2-4" category would have been the most accurate call (some isld 5"s ). Overall, my Friday AM forecast did indicate the stronger trends, along with the timing and driving conditions being spot on. Enjoy the winter wonderland this weekend; now on to the next challenge.....

recent snow amounts /per NWS/
Snow map

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 Previous blog:
In a winter where true Arctic air infiltrations (a.k.a. pests this winter ;-)) have been as rare as its snowstorms, an impressive plunge of Arctic air will again be our weekend guest, arriving this Friday. Ironically, it was exactly a month ago in January on Friday the 13th, when the first in a series of Arctic waves surged south into the Great Lakes. In any other winter, these plunges of Arctic air and resulting temperatures would not be very noteworthy but given the extraordinary mild winter thus far, they are and it will be noticed! High temperatures will actually drop to below normal levels for a couple of days in the teens and 20s. Normally as we move into the second week of February, our highs across Southeast Lower Michigan average in the 30 to 35 degree range while lows place between 15 to 20.  

                                                   250 MB Upper Jet

                                                                       Surface Map

Likewise as in that first mid January visit, this new Arctic air pest will take its harshness out on the inhabitants of Southeast Michigan late Friday into Saturday but then; quickly begin to slide off to the northeast as the weekend comes to a close on Sunday. Snow showers and squalls we also accompany this latest blast (as it did back in January). The very latest indications are enough moisture will be transported into Southeast Michigan as a weak wave of low pressure transverses the front (see second map) to bring 1 to possibly 3 inches of snow across the region. Gusty north winds and falling temperatures later on Friday will exacerbate driving problems. Motorists driving Friday up through Michigan should be prepared for this winter weather and any subsequent lake effect snows with higher amounts.

                                                                        Surface Map

After this weekend, indications are the action will focus back to our southwest early in the week as the Jet Stream begins to re-group out over the Plains. At this time it looks as though some light snow or mixed precipitation may move back into the region toward Valentine's Day.

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

Wicked winter weather remains at bay on Ground Hog Day over Southeast Lower Michigan. Reasons why remain just as relevant now as discussed in my Mid Winter Outlook.

Mid Winter Weather Outlook Update issued 1/22/2012

Strong Solar Storm Arrived Tuesday 1/24/2012...Auroral Forecast From NOAA

A strong solar storm arrived in the earth's atmosphere on Tuesday morning. An neat experimental web site from NOAA's Space Weather Prediction Center does an auroral forecast which displays where the Aurora Borealis (or northern lights) are expected based on solar wind and the interplanetary magnetic field /IMF/.

Also; check out these Aurora Borealis vidoes, courtesy of You Tube and The Inquisitor.

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

Mid-Winter 2011-12 Update...What Has Been Going On and What to Expect The Remainer of The Winter

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

                                                                    1/22/2012

Well this has certainly been a difficult winter to initially forecast; then observe. Some of the main issues I stated in the Outlook and subsequent blog troublesome winter have unfortunately materialized. 

From the Outlook:

The Ever Elusive NAO/AO

The other main ingredient in this winter’s weather (like any other) is of course, 

the trend of the North Atlantic Oscillation/Arctic Oscillation throughout the winter. 

Of course, this is the biggest challenge to the forecast and potentially, has the 

biggest bust potential. While trends with La Ninas and El Ninos are seen (and 

these are not always consistent, either) the NAO is highly elusive and generally

trends are seen only a week or two out. The near term has been neutral to positive

reflecting the recent mild weather but what of the projected? Seems as though

the model ensembles are having a bit of trouble.

The first and utmost problem with this winter is one of the main issues every winter, the North Atlantic/Arctic Oscillation phase. Most forecasts this winter were counting on a negative or at least neutral average of the NAO like the past several winters but this surely has not been the case. The NAO/AO has been in positive mode (sometimes strongly) since last fall. Of course when the NAO/AO is in a positive mode or phase, the real Arctic cold air remains bottled up around the polar regions and other far northern latitudes; one of the reasons why Alaska has been so cold and stormy this winter. In the strongly positive NAO/AO phase, basically the Arctic Jet stream retracts northward somewhat as it circumnavigates around the North Pole. It has been only recently where the NAO/AO has been transitioning toward a neutral or occasionally, a negative phase. It is interesting to note that the projected phase of NAO/AO is mainly neutral-negative early, then becomes quite variable again but with a subtle trend downward as of 1/21/2012. One positive note in this recent transition is the fact it does reflect the Winter Outlook's analogue's call that the second half of the winter would contain the worst of the weather: being the coldest part of the winter and back-end loaded with snowfall. Of course the obvious question that arises; will the NAO/AO trend continue?

The second reason why much of the lower 48 and Southeast Lower Michigan have been mild is also the reason Alaska has been so stormy: the strong northern Pacific Jet Stream discussed in the Outlook and later in the Troublesome Winter. This part of our Winter Outlook equation is there, in spades. The jet has been so strong, occasionally it established a strong zonal flow into the US, ironically not unlike the jet seen in moderate to strong El Ninos; just further north. The analogue projected Pacific Jet "did it's part" to verify our expected winter jet pattern but it's partner, the Arctic Jet in which phasing or pardon the expression, "mating" was routinely expected but has occurred, infrequently. Therefore, much of the country has actually experienced in my opinion a "pseudo El Nino" winter with the strong Pacific jet bringing modified air into the country. In addition, many times this strong jet off the Pacific dug into the West and actually creating ridging into the center and eastern part of the country in the absence of the Arctic Jet.  This in turn; brought periods of above to well above normal temperatures. So much so, that up until recently Southeast Lower Michigan had experienced perpetually late fall-like temperatures with readings the first half of the winter averaging a good 5 degrees above normal!

Visualizing this further:
The Pacific Jet of the analogue's winter (Fig -1) upper wind pattern has been fairly accurate; while the Arctic Jet pattern has been focused further north across Alaska east into north and central Canada. It's interesting to note that between these patterns there was a notable absence of wind or "lighter wind path" west to east, across the center part of the country just north of sub-tropical jet. In the absence of the Arctic Jet, which has retreated north, one can visualize how the intense Pacific Jet would easily flood across the country in this basic analysis of the pattern (fig-2) (and remember to take into consideration the Arctic Jet being further north).

                                                                              Fig -1

                                                                              Fig - 2

Ok, this is the past and present; what about the future?

While we have definitely seen a pattern change of late, the NAO/AO is still in a transitioning or "unstable" pattern which has been even more erratic than usual, which makes forecasting the second half of the winter just as troublesome (or difficult) as the first. But, if you know me by my years with NWS and my Southeast Lower Michigan Outlooks (and now Weather Historian Blog), I'm not going to let a "little" adversity get in the way. If I fall on my face, so be it...it wouldn't be the first time nor the last. And, using the famous pep-talk line; "Get up and put one foot in front of the other and get on with it!" ;-)

Temperatures:
Well, obviously taking into consideration the first half of the winter, my original call of 1 to 3 degrees below normal was much too cold. Therefore, adjusting for the exceptional warmth first half of the winter (with an average departure through mid January of +5.0) , I now expect the entire winter average temperature to range 2 to 4 degrees above normal. With these departures, one would expect the second half of the winter to be colder than the first half but I still look for it to average around 1 to 3 degrees above normal.

Snowfall: 

The snowfall issue was visualized and foreseen in the original Outlook:

"The ranges of snow each month (from the analogues) is extraordinary with some ranges two to nearly three feet. Just in February alone: Detroit ( 2.6" to 31.7" ), Flint (1.5" to 31.4") and Saginaw ( 3.7" to 34.2"). This handily shows this incredible range of snowfalls. Really, the only thing I can gather here is that these set of winter's seemed to be more back-end loaded with the worst of the winter coming the second half."

"If the storms ride further north than expected, this could also botch up the temperature forecast too with the upper level ridge holding stronger in the Southeast."

The second quoted line here has happened and mainly due to the positive NAO/AO and subsequent retreat of the Arctic Jet. My original snowfall call here was normal to above snowfall and thus far, most areas have seen around 6-10" below normal (and one decent storm would take care of that); whereas the Saginaw Valley region has had about normal snowfall.

Taking all this into account; I look for the majority of the region to still see close to normal snowfall (within 6") but with a few areas above that mark and a few below.

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

Third Wave of Arctic Air Reinforcement to Arrive Thursday...Most Snow of the Season Thus Far Arrives Friday /Update on Actual Snowfall/

1/21/2012-
The system produced generally just 1 - 3" snowfalls across much of the region. The heavier band of snow ended up falling just south of the region across northern Indiana and Ohio where I saw heavier reports of 5 -  8" as the bulk of the moisture stayed south of our region.  Another related problem here was snowflake size which was very small with the very cold air in place prior to the event. My forecast of generally 2 - 4" with areas of 3 - 5" was a bit too aggressive in this Saturday morning quarterbacking review with a 1 - 3" call better suiting the event. 

Snowfall reports from NWS White Lake Mi
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 Original Post

A quick third shot of Arctic air will plow through Southeast Lower Michigan Thursday. This reinforcing blast of Arctic air will be accompanied by gusty winds, snow showers and flurries. While accumulations of snow will be around an inch or less, falling temperatures and blustery winds will make for an uncomfortable January day for sure.

The better snow maker will move into Southeast Lower Michigan quickly on heels of the Thursday system during the day Friday. Our extended and now short term models have been fairly consistent with this system with its broad area of moisture, good forcing and lift which will squeeze out any available, layered moisture. While the center of the actual low pressure will be far south over the lower Ohio Valley, moisture will be flung far to the north over the Southern Great Lakes. Even though the moisture and precipitation amounts are not high with the system; they will be more than sufficient, given the dynamics of this system, to give much of the region its best snowfall of the season (considering the previous light amounts). I'm generally looking for at least 2 - 4"  of snow but with higher areas of 3 - 5" possible in the heaver snow. Even scattered pockets of 6" amounts are not unreasonable given the cold air mass in place and resultant high snow to water ratios of the system. The snow to water equivalent ratios should generally fall in the 15-20 to 1. This means for every .10" of precipitation (or melted water equivalent), snowfall should range in the 1.5" to 2.0" (possibly even as high as 2.5"). There's even a slight risk of some freezing rain near the Ohio border if the warmer moist layer is flung far enough north to clip that region. This system will have to be watched for any type of path change as some of the models are beginning to hint a bit further north with the core moisture. Any updates will be issued if needed in my blog.

Needless to say driving beginning Friday afternoon into Saturday morning will become slippery and dangerous and all cautions should be exercised. 


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

And The Battle Is On! Round One...And Now Round Two /Update 1/15/2012/

Overall, the first wave of cold air behaved well in regards to expectations of snowfall and temperatures in my most recent blog. Generally, "one to three inches of snow"  was forecast across the region Thursday night into Friday with some locally higher amounts possible. As one can see by this snow map through the 13th (courtesy of the NWS) actual snowfall pretty well fit the bill. 

In addition, more snow fell behind the system on Saturday, converging in and around Wayne county with an inch or two of additional snow (and I must say; it was a beautiful scene as the nice size flakes of snow fell while walking in the local snow covered woods). So now it at least looks and feels like winter with temperatures falling off into the teens and some single figures (Sunday Jan 15th) as some breaks in the clouds allowed over the freshly snow covered landscape.
 
I ended the blog by writing:  A second wave of Arctic air will already be charging south for round two of this winter onslaught early next week. Stay Tuned.... 

I also briefly stated in that blog, this next in the series of cold shots of air will be proceeded by a mild surge of air early this week with temperatures shooting back up above freezing. Latest indications are as this wave of cold air approaches late Monday night and Tuesday, some energy aloft sliding up along the cold front should enhance the rain and snow associated with it. This energy should help focus in the development of a low pressure system nearby as the front slides southeast down into our neck of the woods. In response to the upper level support, the low will deepen somewhat as it moves off  to the east out over the eastern Great Lakes. Therefore, the timing of the colder air flooding into Southeast Lower Michigan behind the low on overnight Monday into Tuesday and its subsequent deepening and moisture supply will determine when the rain changes to snow scenario along with how much snow falls. At this time, it does look like some of the area will see some light measurable snow with this system with the preferred area over the Saginaw Valley and Thumb Region. Temperatures under this next Arctic air mass should be at least as cold, if not a bit colder than over the weekend.

If things change appreciably with snow expectations or temperatures, I'll make note of it in my bog.


Now, reflecting back to the upper air plots I posted projected by the NCEP ensemble members last week I stated the following:

"As the two jets align and merge next week, a strong zonal flow is expected to evolve mid month over southern Canada and the northern US. Occasional ridging in the west is also projected to develop and thus, help divert and phase the Pacific air northeast into the Arctic jet over Canada. This would then create a strong west-northwest jet stream across the northern and eastern part of the country".

It is said a picture (or two) is worth a thousand words: Take a look at the GFS projected upper wind pattern at about 39,000 FT /200 MB/ and at 18,000 Ft /500 MB/ for roughly mid week. It is easy to see the jet core here over the Northern Plains with a wind jet max of around 150 knots. The second map shows the strong Pacific and Arctic jet at the "jet stream" level of 18,000 feet /500 MB/.

                                                                           

Another wider western view of the same time period shows this strong phasing nicely, initially over the Gulf of Alaska and additionally over North America!   

Coming in the next week or so: The Mid-Winter Outlook Update

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

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Initial Blog of January 12th

In my previous post, I displayed and discussed the NCEP model ensembles regarding the up and coming changes I expected by mid January.  I gave details of these changes and the likelihood of the alignment of the jet cores in the swiftly moving Arctic and northern Pacific jet streams by next week. This, in turn would set up an ongoing battle into next week of the milder air we've become accustom to and the Arctic air hovering over Canada.

Well, the first onslaught in a series of Arctic blasts is slated to surge through the region by Friday /good 'ole Friday the 13th - so don't temp fate, watch you driving ;-)/.  This "Arctic air" (and I use the word loosely since at this time of the year, it could be a lot worse) will settle in as a weekend guest. This abrupt change in air mass will be accompanied by snow showers and squalls, surely enough to leave untreated roads icy & dicey through Friday. This won't be a big system as far as snow amounts for Southeast Lower Michigan still; the system should deposit one to three inches of snow (but locally higher amounts are possible if she wraps up a bit better and is aided by Lake Huron). Much worse lake effect snow squalls are expected on the west side of the state downwind of Lake Michigan into Northern Indiana so motorists heading that-a-way should also be advised.

This "weekend guest"  (or maybe it should be "pest") of snow and cold will bring the first interval of notably below normal temperatures this season, quite atypical by this time. Temperatures across Southeast Lower Michigan during the period will be mainly in the teens and 20s with some overnight lows possibly dipping into the single figures (especially with the snow cover and partial clearing). Therefore, it truly will be a shocking reminder to the inhabitants of Southeast Lower Michigan what season this truly is...winter. On the brighter side, it should give the winter weather enthusiast (of which I am one) something to talk about and the winter weather sport persons, something in which to be out and about.

However, as I mentioned above, she'll (after all, La Nina is running the show this winter ;-)) just be a weekend guest and will quickly scurry off to the east later Sunday and be replaced by a sharp moderating trend, in time for Martin Luther King Day.

A second wave of Arctic air will already be charging south for round two of this winter onslaught early next week. Stay Tuned....

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

Bitter Arctic Air to Pool Over Canada Mid January

NCEP ensemble model members continue to advertise a change in the upper air pattern across the northern hemisphere in mid January. The some of the coldest air of the season is projected to relocate or "drain" from Siberia, Alaska and the Polar regions and settle east southeast over northern Canada over the weekend into next week (14th-21st). This in turn will "recharge the freezer" so to speak up in northern Canada. To check on the evolution of this projected ensemble model pattern, click here.

In addition, this air is expected to migrate south at times into the US. How far south this air is able to infiltrate the US is questionable since the northern Pacific La Nina jet stream has been strong and has acted as a door, shuting off much of the true Arctic air this season. 

 
As the two jets align and merge next week, a strong zonal flow is expected to evolve mid month over southern Canada and the northern US. Occasional ridging in the west is also projected to develop and thus, help divert and phase the Pacific air northeast into the Arctic jet over Canada. This would then create a strong west-northwest jet stream across the northern and eastern part of the country. It is way too early to tell how much of this true Arctic air projected to pool over northern Canada will be caught up in this strong west-northwest flow and make it into Southeast Michigan. Stay Tuned... 

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

Oh Winter Where Art Thou??

The way things are going, pretty soon the Winter of 2011-12 will become to be known as the year without a winter. A bit exaggerated I know but the winter thus far has not only been exceptionally mild, it's been exceptionally BORING! In the first five weeks of "winter", temperatures across Southeast Michigan have averaged in the lower to mid 30s...not the highs...the averages or means. Our normal highs this time of year are generally in the lower 30s, so this is pretty much where our temperature averages have been. In the past five weeks, the high temperatures across the region have averaged around 40 degrees...give or take a degree. So, if you've thought the weather has been behaving and feeling like a "perpetual late fall", then you are right on the money. Average high temperatures across Southeast Lower Michigan late fall, say around Thanksgiving, are generally in the lower 40s.

So what gives? Did mother nature suddenly become senile lately and just forget what season we are supposed to be in? Did she fail to read the Winter Outlook and behave accordingly?  You'd think so ;-).  But seriously, the reasons I discussed on why we have been so mild into Christmas Day, have more or less persisted into early January.  However, in that same discussion I also reasoned and explained why I expected a pattern change to commence in January. This explanation also jived well with the mild analogue Novembers I researched and posted along with the difficult winter to forecast ahead! 

However, I'm not blind to the fact that the mild and lack of snow beginning of the winter will obviously affect the outcome of the winter 2011-12 statistics! Therefore, in that same vein, I will be updating my Winter Outlook within the next few weeks to account for the exceptionally mild and boring beginning. Oh, I'm not giving up on winter just yet and I believe the notable change I talked about at Christmas time is now happening, albeit slowly.


Summarizing...Mother Nature has become a pain in the Butt!

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