- Oct 1, 2020

TO FROST OR NOT, THAT'S THE QUESTION...

The wicked winds of the west were blowing today with gusto Wednesday! Gusts of 40-45 mph were common with the Quad Cities measuring a top speed of 48 mph.

The winds were the result of a strong surge of cold air that's arriving from the north. You can see the arc of chilly air pushing steadily southward on Monday's early evening satellite image.

These clouds are going to be the big forecast challenge the next 48 hours as they will have a significant impact on temperatures. The cold air aloft should see to it that low clouds and stratus build again Thursday. A few spotty showers are also likely but they will be light and very much of the hit and miss variety. Considerable cloudiness will hold highs well into the 50s. The GFS shows this and is very close to the EURO.

That brings us to Thursday night and the prospect of frost. If skies clear and winds diminish the potential is certainly in the table and the GFS is in that camp. Here's what it shows for cloud cover at 3:00 am. Clear skies are denoted by a zero, 100 overcast.

The fair skies on the GFS allows lows to crash into the low to mid 30s, upper 20s in some of the valleys of NE Iowa and SW Wisconsin.

On the other hand, the EURO has clouds lingering much of the night acting as a blanket.

As a result the EURO is 10 degrees warmer and does not show the frost threat.

Both models have been staunch on their solutions the past couple of days so this is a tough call. I do think that clouds will break (if not clear altogether at some point) but how extensive and fast is impossible to know. As a result, I prefer a middle of the road solution for now with mid-to upper 30s indicating the potential for at least scattered frost exists. Best chances would be in the NW half of my area. However, a freeze would not be in the offing and the growing season would continue. We will know much more on the threat Thursday afternoon as critical trends begin to unfold.

The next order of business is rain chance Saturday, especially Saturday night. Models continue to trend further southwest with the system but are in decent agreement on track and intensity compared to yesterday. As a result, it appears shower chances are in play for all of my area but amounts are nothing to write home about as moisture is slow to enter the system until it's off to the east. Any lingering showers would end early Sunday morning east of the Mississippi. Here's what the EURO shows for rain totals.