12/08/2009-12/09/2009 Winter Storm

[Joel Wright]

The GEM remains remarkably consistent and therefore is my model of choice. GFS appears to be doing quite well too. NAM is still playing catchup to the idea of a stronger solution, and therefore little confidence with that.

At this point there's no question that a major snowstorm will impact much of the Midwest and Great Lakes. Many of the models continue to advertise a sub 980mb surface low by the time it enters lower MI Wednesday morning. Since the storm won't fully close off in the mid-levels the rain/snow line will remain relatively close to the low pressure track.

The grand prize snow totals should line up from near Falls City NE, to Lamoni IA, to Dubuque IA, to Madison WI, to Fond du Lac WI. In these areas 8-12" is a good bet. A few isolated amounts higher than that are possible with any convective element. Even areas well to the north of that will see very respectable snows due to high ratios and 850mb frontogenesis. Wouldn't be surprised to see areas as far north as Minneapolis come in with 6-8" of fluff.

Still a day or so to watch trends, but the overall scheme of things is starting to become much clearer...

 

[Dustin Wilcox]

Unlike many, I don't get jollies from winter weather forecasting, thus I haven't been following this system much beyond peaking at the models snow totals briefly each night. That being said, both the GFS and NAM have been quite consistent in some convective type snowfall rates across SE NE. These 15" + totals are impressive totals given the short duration of the event due to the speed of the system, probably more realistic to count on about 2/3rd of what totals the GFS keeps placing across the area, though even a solid 8" snow with the 30+ mph winds will make things quite adventrous across the area by late Tuesday.

H\As of right now its been snowing since around 4 PM and i would guess that we have about 3-4inches on the ground.

Solid 3" on the ground in Beatrice, with another 8" or so on the way, we'll probably actually have a foot around by the time the winds start to really blow.

 

[J West]

Storm forecast for first significant winter weather event gets all Milwaukee meteorologists saying storm will hit Chicago, giving Milwaukee just an inch or two.

Storm decides to go north of forecast track and slam Milwaukee and give Chicago just an inch or two.

I will eat my words if this doesn't happen this time around with this storm.

You've got this backwards. If this (or any) projected winter storm track moves north of Chicago, Milwaukee usually gets nothing or rain...not slammed as you claim. The further south into Illinois a storm track is during winter, the better chances SE WI gets the heavy snow.

Also, you apparently haven't been paying attention to the forecasts, as Chicago proper will not be slammed as hard as the western suburbs or places like Rockford or Sterling. Currently, Chicago proper is not included in any advisories or watches because of the forecast track of the low, even as winter storm and blizzard watches are hoisted all around them...not to mention the modifying effect the relative warmth generated by the city this early in the season.

The crew at MKX are still not confident that the present storm will track far enough south to allow all snow for Milwaukee and points south.

 

[Chris Carter]

3 different scenarios. The low tracks across the KS/OK border and closes off for a little bit before moving into the great lakes region which enhances the snow across the plains, pointed out by the GEM/EC. The GFS is right on target with the GEM/EC as far as track goes, but it never closes off the low significantly changing the snow amounts and winds. Then there is the NAM which does the same as the GFS, never closes off the low but it has low track further north.

After the GFS performance of Sunday's system, I'm going with the NAM as it handle the track very well, it was just too strong on the amounts. But in my experience with winter weather, no matter how accurate or persistent the models may be, nothing is for sure when it comes to winter weather until it happens.

 

[Mark Sefried]

Models consistant now with the heaviest snow track across Eastern Iowa into North Central lower MI roughly along a Des Moines Iowa Northeast to a little North of Saginaw, MI. This will be a little north of the 850 mb low track where the heaviest snow axis usually sets up. All I can say is thank goodness I should be SE of the low and just get a glancing blow with the snow of maybe a few inches at best. Talk about a freakin bomb, lol.

 

[Robert Dewey]

12z UKMET is out, and fairly consistent... tracking a 988mb low just W of KSTL at 6z 12/09, to 980mb just SE of KORD at 12z 12/09, to 970mb just E of KAPN at 0z 12/10. That looks pretty reasonable; 12z GFS is nearly identical with the low track and strength, until the system reaches Lake Huron, in which case the UKMET is 5mb deeper. 0z ECMWF also similar with the track, and is 2mb deeper than the GFS. 12z NAM is the outlier, it's weaker with the SFC low and further NW.

I'm going to say that the center of the heaviest band of snow will setup along a SW to NE axis of 50 miles on either side of a line from Superior NE, NE into Ames IA, NE toward Green Bay WI, and NE towards Traverse City MI and Alpena MI. Areas further SE of that envelope (St. Joseph MO, Moline IL, Mount Pleasant MI) will be flirting with the R/S line, cutting down significantly on totals. With that said, those areas will still likely pick up a few inches... and with the wind, could easily create blizzard-like conditions.

 

[Mark Sefried]

Agree with Robert on this one. I thought Saginaw was further north, lol. A little North of Des Moines, IA to Alpina, MI line looks good to me for a heavy snow axis also.

 

[Mike Kovalchick]

Looking at the models and BUFKIT soundings..the Gaylord, MI area stands to get some of the higher system totals along with a healthy dose of WNW wind lake effect to backlash behind the system. Looks like 24"+ possible between Tuesday evening and Friday evening. If model trends continue, I will head back up that way tomorrow evening for the big show.
(I was up near the Pellston area last Saturday to watch a rather impressive snow band crash ashore and impact the Boyne Higlands.)

 

[Joel Wright]

I expect the rain/snow line to back as far west as southeast IA, to extreme southeast WI Tuesday night. Pretty much right through the Quad Cities. The heaviest snow should fall just west of that from south-central IA to southern WI. Still think the heaviest totals will line up from Lamoni, to Dubuque, to Madison and Fond du Lac. 8-12" looks quite likely here. Keep in mind that even well to the northwest of this band very respectable snows will be seen. As far north as MSP they are in line for several inches of dry, fluffy snow.

Chicago is in a very interesting location with respect to this storm. They'll start out as snow as the WAA wing envelopes them tomorrow, but will quickly swing over to rain from south to north during the evening. There could be a huge range in accumulations across the metro. An inch or two in the far south to as much as 7-8" out near Crystal Lake and Woodstock.

The GEM, GFS, and Euro all remain very consistent so confidence is relatively good with the track. UK has come into agreement with the last several runs as well. The RGEM looks a little too bullish in closing off the mid-level circulation early on, and thus bombing the surface low to 973mb west of Chicago. It, along with the NAM appear to be the outliers. Big surprise there huh? LOL

 

[Robert Dewey]

Looking at the models and BUFKIT soundings..the Gaylord, MI area stands to get some of the higher system totals along with a healthy dose of WNW wind lake effect to backlash behind the system. Looks like 24"+ possible between Tuesday evening and Friday evening. If model trends continue, I will head back up that way tomorrow evening for the big show.
(I was up near the Pellston area last Saturday to watch a rather impressive snow band crash ashore and impact the Boyne Higlands.)

I also think northern lower MI will be the "winner" with this event. Not only does the low wrap up tightly over Lake Huron, you'll get plenty of lake enhancement ahead of the system, and then pure lake effect behind it. I'm sure this will be one for the record books up there. I think everyone between Grayling and the Bridge is going to get absolutely hammered.

Also what will be interesting is how the low will act over Lake Huron. There have been a few cases where the warm(er) waters of Lake Huron have caused local deepening of surface lows, further increasing wind gradients. One such case was the November 1913 storm - http://en.wikipedia.org/wiki/Great_Lakes_Storm_of_1913 - which featured waves >35ft and wind gusts up around 100mph.

 

[Chris Carter]

After looking at the latest runs from the GFS/GEM, I can see why OAX has been mentioning about dropping some counties from the WSW as they might not appear to meet the criteria since the track is consistently too far south. I think Omaha will just barely make the winter storm warning criteria as they get 6-7", i think here in Lincoln we will more than likely get 8".

 

[Mike Kovalchick]

I also think northern lower MI will be the "winner" with this event. Not only does the low wrap up tightly over Lake Huron, you'll get plenty of lake enhancement ahead of the system, and then pure lake effect behind it. I'm sure this will be one for the record books up there. I think everyone between Grayling and the Bridge is going to get absolutely hammered.

Gaylord is located at the "divide" which seems to maximize system snow there. (Easterly winds will bring in some Lake Huron effects as well.)

Behind the storm, the lake effect parameters look impressive to say the least:

Delta T's in the "Extreme" range.

Little wind shear.

Winds out of virtually the same direction for 48 hours which should allow for well developed snow bands/overall good band morphology.

WNW flow which targets the Gaylord area.

35 Knot boundary level flow which causes good inland penetration and plenty of low-level omega due to terrain effects/convergence.

Warm lake waters...wide open Green Bay.

Adequate humidity.

Little diurnal effects due to the low sun angle and snowcover.

The only real negative is dentritic growth layer will be very close to the surface due to the exceptionally cold air mass which could limit snow flake sizes. However, with it being so early in the season-the heat flux off the lake will likely mix enough warm air in the boundary layer to keep the snowflakes sizeable. (I've seen colder air masses at the same location still generate big snow flake sizes for whatever the reason.) I also would rather see the winds have a bit more veered to pull a Lake Superior connection into the mix.

 

[Chris Carter]

18Z GFS has now got the low tracking further south into the TX panhandle and into central OK and weaker at 996mb. Now it looks like Chicago is in the cold sector of the storm and with more precip.

Think this might be right as the isentropic warm advection is beginning to break out light snow over Central KS and back into the OK panhandle, which a little south than the previous runs of the GFS.

 

[Mark Sefried]

Based upon today's 12z models, If I was snow chasing my target city would be Waterloo, IA. A major town, on an interstate, and just NW of the 850 mb low. Not to mention just out of town there are rolling hills/flat terrain for all of the snow to blow around. If one were to find a motel in a small town off a major Interstate, they may be stuck there for several days. I imagine a few may be chasing this one.

 

[jshields]

warnings now out for a HUGE section of the midwest, also blizzard watches now out for eastern ne and all of iowa. here's the latest snowfall map from the omaha wfo. i know someone said there was doubt by the office on how far north the heavy snow would fall. apparently they've decided with 10-12" forecast in omaha!! also the sioux falls south dakota office has added warnings all the way up to se s. dakota and nw iowa. some incredible wording by the des moines office as well with 8-12 FEET drifts possible!!

http://www.crh.noaa.gov/news/display_cmsstory.php?wfo=oax&storyid=43804&source=0