Sunday, January 19, 2014

Early February 2014 Forecast

This post will address the predicted weather pattern for the first half of February.

January 23-24 500mb height anomaly forecast
As we enter February, expect the pattern to be on the warm-up, as ridging over Japan on January 23rd and 24th means ridging over the US from a January 29th to February 3rd period. Because the ridge in Japan is rather progressive, I wouldn't doubt we see the same result here in the United States when the ridge comes along for early February. By the time we reach February 5-7, it appears we will see another shot of Arctic air.

This image shows an analysis (not a forecast) of the 500mb height anomalies over the Pacific, as of 6 PM Central Time last night. We can see the deep negative height anomalies over the Bering Sea, and the identifier of the Bering Sea Rule, Joe Renken, sees this as a signal that the February 7-12 period will see significant cold weather. I agree with this idea, and it does look like the first 10 or so days of February will be characterized by an up-and-down weather pattern.

GEFS 500mb height anomaly forecast for January 31

I expect we see tentative settling-down of the pattern by the middle of the month, as persistent high pressure just south of the Bering Sea at the end of January indicates we could see a zonal flow situation not unlike we saw earlier this winter, where high pressure dominated the Southeast and stormy weather affected the West Coast. Because of this Southeast ridge returning, I expect we see the late January East Coast snow zone retreating back into the Midwest and Plains. Unfortunately for those in the East, this winter does look to be confined more to the Central US as opposed to coastal regions.

To sum up:

•February 1-7: Warming up in the Central/East US before a cool-down at the end of the period.
•February 8-14: Potentially intense cold in the beginning and middle of the period before a relaxation into more moderate temperatures, especially in the South and East.