Yesterday we talked about the developing blocking pattern in the atmosphere (negative NAO) and how this gives hope to snow lovers in the Mid-Atlantic region even though time is running short this winter (spring training games begin this weekend!). The latest 12Z GFS model run continues to suggest negative NAO will persist into early March and the height and temperature anomaly maps are quite impressive for cold and blocking during the first week of March.
The first map below shows the 11-15 day 500 mb height anomaly chart for the northern hemisphere and it is reflective of a blocking pattern in the northern latitude region from Hudson Bay, Canada to Greenland with significant positive anomalies (orange, yellow).This type of pattern would likely force some cold air masses into the central and eastern US and indeed a sharp upper-level trough (negative anomalies) is indicated in the eastern US on this map for the 1st week in March (blues, purples).The second map below is very impressive for its forecasted negative temperature anomalies at 850 mb in the central and eastern US (blues, purples).
Bottom line, an interesting “teleconnection” pattern is just now setting up for this part of the country and it looks like it’ll continue right into March and perhaps even peak in early March with respect to temperature departures from normal.(Both maps below from the raleighwx.americanwx. web site).