Well, I've been telling you for some time a big change was coming and by golly it's here. Temperatures were down 25-30 degrees Wednesday and now that the chill has emerged, it will dominate the weather pattern for much of the next 10 days. Here's some temperature reports at 6pm Wednesday evening. 80's in lower Michigan, 20s in northern Minnesota!
That type of extreme thermal boundary is what drives storms and it sure looks like a big one will pound the Midwest this weekend. It looks to be the big enchilada with everything from snow to severe weather on the table. As it stands now, my area should avoid both the snow and severe weather thanks to a track that takes it directly overhead.
Here's a cool animation of the storms evolution at jet stream level (500mb). You can watch the energy dig into the southwest Thursday night, close off and then roll right over northeast Iowa Sunday night. A text book example of a strong mid-latitude cyclone. Classic!
It's also fascinating to watch moisture get injected into the system and then be drawn north into the deepening storm. You can see that in the PWAT (precipitable water vapor) animation below. Moist air is is green, blue, and pink. Watch it coming up out of the Gulf!
In this next animation you can watch as the surface low forms in Texas and then make its way north into Iowa and eventually Wisconsin. It deepens to about 988mb.
One change that might be significant for my local area is the 18z track of the storm on the GFS. Today's runs have deepened the system even more which has pushed the track further northwest. If that happens, and it's possible based on the incredible dynamics, a short burst of warmth could materialize late Sunday afternoon or evening. So, instead of the 40s suggested previously, temperatures could actually go into the 50s and 60s for a short period of time. This trend has only shown up on one run so confidence with this development is still low.
Anyway, here's the meteogram for Cedar Rapids. It shows highs going from 48 Saturday to 66 Sunday and then back to 44 Monday.
The Quad Cities gets even deeper into the warm sector and the GFS shows a 69 over that way Sunday afternoon after a 47 degree high on Saturday.
With the track further northwest the snow that's expected could also trend more in that direction as well. Here's the EURO snowfall forecast.
The GFS shows this for total snowfall.
Significant rain will be widespread and in some parts of Illinois and Missouri it will be excessive where amounts of 6-10" are shown on both the EURO and GFS. Lots of other places are looking at 1-3" totals. Take a look at both models starting with the EURO.
As I wrap this up it's very clear that the weather is going to be a big story in the Midwest for several days to come, especially this weekend when the big enchilada arrives on the scene. If you are into weather, particularly the dynamic and extreme type, this is going to be a fascinating period. This is the stuff I live for! Roll weather...TS