Sunday, April 28, 2013

Late Season Snowstorm Targets Midwest

The GFS model is predicting a late season snowstorm will hit the Midwest and western Great Lakes regions over the next 5-10 days.

Shown above is the accumulated snowfall forecast from now until May 6th. We see a swath of accumulating snowfall stretching from the eastern half of Iowa into Wisconsin and the Upper Peninsula of Michigan. The amounts in this swath of snow are anywhere from 2 inches to nearly one foot, with the latter end of the spectrum centered over Iowa and the U.P. of Michigan. Accumulating snow even goes as far south as Missouri, with that state and Illinois getting in on amounts as high as 2 to as much as 4 inches in isolated spots.

I am incredibly skeptical of this forecast. The GFS model is known to have a cold bias when it comes to winter weather, and the impending pattern change does nothing to help forecast accuracy. In my opinion, if this scenario even works out, we would see a chilly night in IL/MO without any snow, and maybe some plowable snow into Iowa- certainly not at the level being predicted. I find it hard to believe that the GFS model has a viable case at this point in time.



Anonymous said...

this comment does not have anything to do with this post but in a way it does - this spring is just plain wacky!!
i am a farmer here in northern kansas and yes nws says it will snow overnite wednesday. i have seen may snow before but what bugs me is the trees normally by now they have leaves on them but most dont also by now most pastures are green with lots of new grass growing but they are no where near that. the last 30 days have had more moisture than all of last fall and winter combined. is this more than a sign that the reat of spring and summer are going to be wacked to. maybe cooler and wetter than normal
would like your opinion

Andrew said...

Spring should be put on hold until mid May. After that, a better, more springlike pattern could be in the cards. Best of luck to you, I know farmers have had it pretty rough recently.

Anonymous said...

Same here in Palmer Lake, Colorado, the grass is coming in beautifully, or at least the newer grass that hasn't been killed by extreme cold is, but the trees have really yet to even bud for the most part, a sign that winter is not done with us yet, in fact, Andrew, your snowfall model there may not be so farfetched, at least for Colorado, as the NWS is now forecasting around 5"-10" of snow for Palmer Lake and surrounding mountain locales, and highs that may not even get out of the 20s for Wednesday...lows in the 10s, I don't know about you guys, but going from near record highs to near record lows in such a short period of time over such a large area is likely going to spell trouble, I would almost bet on a pretty nasty severe weather outbreak from such a huge temperature contrast, in fact, it's almost a certainty in my opinion.
By the way, I do agree with that farmer's question...
could it really end up being a wacky summer from the Rocky mountains to the upper Midwest this year.
One thing is for sure, it seems like we are continuing to see wetter and more unstable conditions across the major drought areas, let's just hope we can keep it coming.

Ray Timmons said...

Iowa, southeast Minnesota and into Wisconsin look to see potentially a few inches, but not a foot as indicated by this model output. That tail of snow branching out into Illinois and Missouri is not there today. It was certainly a surprise to us here at the NWS in Romeoville, IL, and we too were thinking it can not be right and didn't even bother putting it into our forecast discussion knowing it was not a valid solution, and it in fact isn't. Don't worry folks, there no longer looks to be any snow, let alone accumulating snow across Illinois. Far northern Missouri could see some, but none that will accumulate. Models have had major trouble with this huge closed low developing. Typically, closed low's are not that potent, but this one is a rarity. It will hang around into next weekend, but the warmth will build back in next week.

Eric said...

Interestingly, if it snows with this next storm system in the Minneapolis area, it would be one of the first major May snowstorms since 1954. At that time, like what's being observed now we were in a cold PDO warm AMO regime, and also 1954 seemed to fall near the bottom of the solar cycle, and this is a trend I have noted in late season Minneapolis snowfalls, in that many of them seem to occur near the peaks and minimums of the solar cycle. Also, that following hurricane season in 1954 was devastating with 3 major hurricanes on the east coast, and other years with major late season snows in Minneapolis like 1933 and 1893 also were devastating for the US, and both years also fell on the extremities of the solar cycle, like this year. Interesting to say the least and this is something I talked about in my latest post on Apr 21 at weatheradvance.