THREE DOG NIGHTS...
Three dog night-definition
A very cold night. Back in pre-central heating days, on nights when a thick quilt wasn't available or didn't provide enough heat, rural dwellers might take a dog into bed to provide additional warmth. Chilly weather called for one dog, even colder for two, but when it was cold enough to freeze a brass monkey, you'd make room for three dogs.
Well, as far as I'm concerned, by mid-November standards it's cold enough to freeze a brass monkey! Put all the dogs you want on the bed and if you have a brass monkey, do what you do to keep it from freezing.
It would be an understatement to say this was not an abrupt change. Even though I saw it coming more than a week ago, it's still harsh reality to swallow. This meteogram for Cedar Rapids shows the sharp change nicely starting November 10th.
In Moline, the maximum of 78 on the 10th was a record warm high. This Saturday, if the mercury gets no more than 23 (which is the projection), that would be a record cold high. The old flip flop. This is what the HRRR is indicating for highs Saturday.
So basically, we are now in the epicenter of this cold outbreak. Highs both Friday and Saturday will hover in the upper teens north to the low 20s elsewhere. Due to clouds in the cold cyclonic flow and strong winds, temperatures won't be that much colder at night than what we see diurnally, generally mid to upper teens, slightly colder Sunday. Here's the 500mb jet stream structure delivering the cold. Note the strong cross-polar flow that originates in Siberia.
That essentially creates below normal temperatures across the entire continental United States.
Winds chills will be in the single digits and teens from now on out until Sunday afternoon when they may sneak above 20 in the far southwest. The worst will be Saturday night when sub-zero chills are expected in the north, perhaps pushing minus 10 near HWY 20. That's getting pretty close to advisory territory.
A WARMING TREND
As I've alluded to in recent posts, the upper level flow is going to lose amplitude and it's connection to polar air. As such we finally go back above freezing for highs Monday. The warming trend continues through Thanksgiving as zonal flow and Pacific air mix into the pattern. Highs should at least be seasonal in the 40s to perhaps 50 in the south Tuesday and Wednesday. The EURO ensemble meteogram indicates readings like this for Thanksgiving week in the Quad Cities.
Outside of some flurries the next couple days, I don't see much meaningful precipitation potential until Thanksgiving itself. Even that is low confidence, the result of track and intensity disputes among guidance. Due to the energetic nature of the pattern and the struggles models are having resolving it, it's likely to be at least a couple more days before we get a handle on what the outcome will be for Thanksgiving.
With that, grab you dogs, cats, gerbils, etc. and load 'em up on the bed. It's going to be a three dog night weekend. Roll weather...TS