ONE CHILL PILL COMING UP...
Much cooler air is opening eyes around the Midwest as we head into the weekend. What's ahead will be a bit of a jolt as 11 of October's first 12 days were in the 60s and 70s in the Quad Cities (8 of those days were in the 70s).
The pattern reversal is due to a potent upper air low that slowly pinwheels southeast over the upper Midwest and Great Lakes the next 5-6 days. The strong system will deliver a steady supply of chilly air to the region that actually gets even colder early next week. Here's an animation of the 500mb energy evolving through Tuesday. That's a pretty intense circulation.
The average temperature departures over the 5 day period Saturday through Wednesday show widespread cold centered on the Midwest.
The core of the cold is expected to be overhead next Tuesday morning when temperature anomalies on the GFS are at least 20 degrees below normal.
That results in lows Tuesday morning that are in the 20s. Wednesday morning looks frigid as well.
The hard freeze occurs despite brisk winds resulting in wind chills that are shown reaching the level of 10-15 degrees. I for one am not ready for that.
The air is cold enough aloft for snow to accumulate in the upper reaches of the Midwest. It's possible a snow shower might make it as far south as HWY 20 in my far northern counties. The GFS indicates this for snow accumulations through next Tuesday. Look at the lake effect snow in Upper Michigan, northern Wisconsin and even the lee shores of Lake Michigan. Impressive for mid-October.
Closer to my area the tight pressure gradient and cyclonic flow may kick up some brief rain showers Friday and again Sunday and Monday when the coldest of the air arrives. Again, while models don't indicate it yet, the depth of the cold air aloft and the steep lapse rates associated with it could get some snowflakes down to the ground Sunday night or Monday, especially in the north. Something to watch.
Here's what the national blend of models shows for temperatures over the weekend and into Thursday of next week.
As I mentioned there could be a few light instability showers around the next few days but little if any measurable amounts. That's the trend of the next 10 days with the EURO showing this for 10 day rain totals.
That resulting 10 day rainfall departures like this.
The dry weather will only serve to worsen the dry conditions that have developed over the region since August. The latest drought monitor shows the entire state of Iowa now in at least moderate drought conditions. That marks the first time since August 27th, 2013 that 100 percent of that state had some sort of drought classification. About 60 percent of Iowa is now considered in either moderate, severe, or extreme drought.
Parts of NW Iowa and southern Minnesota are in the worst shape with extreme drought showing in some of that region.
The next 30 days ending November 13th the EURO weeklies do show a slightly wetter pattern but nothing that would put a serious dent in the overall dry conditions.
That's enough for now. Have a good weekend and keep that coat handy, you are going to need it, especially early next week as we swallow a big old chill pill. Roll weather...TS