I know it seems like a week since we started talking about this cold air, but it’s still not here yet. It’s right on schedule for tonight, but it’s slow methodically march across the country has had people talking for 5-7 days now.
We still get one more really nice and mild day today with high temperatures in the low 70s in spots under sunny skies. The Arctic front is still over in Tennessee as of this writing and won’t cross the mountains until later this evening.
So you won’t really feel much cold air until tomorrow. We start Thursday actually close to average, but the temperatures will hold steady or even fall as another surge of cold air moves in Thursday afternoon.
Then by Friday it’s just plain old cold around here with highs only in the mid-40s.
Once this cold air gets here it will be sticking around for a while. As the very active and turbulent polar jet stream brings another wave of cold air down early next week. This time there is what we call “cross-polar” flow. Where very cold air from Siberia crosses over the pole and moves into Canada. Notice the subzero temperatures in shades of light and dark green cross over the poll late this weekend on the GFS model below.
GFS MODEL through the Weekend:
Once this cold air gets here it looks to be sticking around. The long-range GFS ensemble mean or average of all that model runs shows consistently cooler than average temperatures over the eastern U.S. through at least Thanksgiving.
NCEP GFS Ensemble mean temperature anomaly:
The CPC(Climate Prediction Center) outlook for days 6-10 still has below average temperatures. Compared to this weekend and early next week though it actually will be slightly warmer. Just shows you how cold this air is this weekend and early next week.