Doing this Monday to Monday now…
Cold and windy in the East – Much below normal temperatures will sit over the eastern U.S. throughout the week. Combined with windy conditions Mon-Wed, it’ll be a bitter start to the week.
The lake-effect continues – The cold air and stiff westerly/northerly winds has caused lake-effect snow storms in the Great Lakes region, and should continue through the first half of the week.
Warmth in the West – On the flip-side of the coin, the western U.S. will be relatively warm as an upper-level ridge sits over the Southwest.
Weekend storm in the East – While the details are far from certain, there is a strong signal that a storm system will rapidly develop over the mid-country around Friday and will move into the eastern U.S. Sat-Mon. This system has the potential to provide a healthy dose of wintry weather to parts of the Mid-Atlantic and Northeast.
La Nina is starting to really show its form this week as it has over the last several days. A cold connection with western Canada will stretch across the Northern Plains and into the eastern U.S. through most of the week, with a slight alteration in the East over the weekend as we see a new storm system develop. The cold air will be trapped over the eastern half of the nation, with some areas in the Midwest and Southeast seeing -10F to -15F anomalies through Friday. This cold air will be accompanied by brisk westerly and northerly winds Mon-Wed, which will make conditions pretty raw. It will also keep the lake-effect machine cranking as the Great Lakes sits under lake-effect warnings as locally significant snowfall is possible. A clipper system will bring some additional snowfall to the northern U.S. during the second half of the work week.
Meanwhile, an amplified upper-level ridge will reside over the Southwest throughout the week, which will keep the Southwest in the above normal temperature category. It will also keep the southern border states very dry as storm systems track across the Pacific Northwest.
A significant pocket of upper-level energy is expected to dive into the mid-country around Friday and rapidly develop into a strong low pressure system over the weekend. This will bring rain and snow to the eastern half of the nation. The models are having a tough time getting a handle on this system, so I will post an update on the event when it gets closer (Thu/Fri). It looks like a big rain producer for the East Coast, with a wintry mix over the Appalachians and snow in the Midwest. It’s looking like it will track over the Midwest and Southeast Saturday, moving northeastward into the Mid-Atlantic Sunday and into Monday. There is also a chance for this system to be a severe weather producer, so that will have to be carefully monitored for the Southeast and Mid-Atlantic as the situation becomes clearer.