Major East U.S. Snowfall Days 6-10 Followed by Vigorous Cold Days 11-15

Chart of the day: U.S. population weight HDD forecast.

Discussion: The latest U.S. gas population weight HDD forecast is similar to 24 hours ago and continues to indicate an accelerating high demand for heating the last third of December.    

Medium-range 6-10 Day Forecast Valid December 20-24, 2022 (24-hour change right)

Discussion: Arctic air surge into the U.S. remains in the 6-10-day forecast. The cold surges into the Gulf States/Southeast U.S. with greater ferocity than indicated yesterday.

Medium-range 11-15 Day Forecast Valid December 25-29, 2022 (24-hour change right)

Discussion: After a significant snow in the East during the 16-20-day period, the East collects a very cold 11-15-day period. Significant warming appears in the West.

U.S. Medium-range Precipitation Forecast

Discussion: The Northeast precipitation in the 6-10-day period is mostly heavy snow. The northwest quadrant of the U.S. is also snowy. Florida stays in a rainy storm track.

6-10-Day East Snowstorm

Discussion: In the 6-10-day period, an East U.S. snowstorm is forecast. GFS indicates a major snowfall centered on Virginia. However, a much stronger storm is indicated by ECM producing a gigantic area of heavy snow for the entire Northeast heading toward Christmas Day. Obviously, forecast confidence is low on amount BUT northeast quadrant of the U.S. locations should plan on a significant snow just-prior to Christmas.