More Maryland Moisture while New England Stays Dry

Monday 830

During the weekend, heavy rain soaked much of Virginia, Maryland and the central and southern parts of Pennsylvania (but not the Philadelphia area). In the I95 corridor, Richmond had 3.6 inches of rain, Washington, D.C., had just over 1.6 inches and Baltimore 0.65, but Philadelphia, New York City and points north and east had nothing. The Canadian model did the best with this system, keeping the rain out of New England by building a blocking high pressure area over the region. Now, the high is starting to expand southward, and the rain will slowly retreat southward as well.

Low clouds have been common along the coast from southern New Hampshire to New Jersey. When high pressure areas build south or southwestward in the spring and the coastal flow is from the east initially, it is very difficult to be sure when the clouds will dissipate. We expect this to happen in New England later today, then tomorrow in New Jersey, Delaware and Pennsylvania. It may take until Wednesday for much sunshine to take over in Maryland and Virginia.

A cold front approaching the region from the west late Wednesday will trigger thunderstorms as it crosses the Great Lakes and Ohio Valley, but there seems to be less support for rain in the Northeast. The Canadian model, which correctly kept the current storm out of New England, is maintaining basically dry weather in the same areas all week. The GFS, which last week had a cold shot for the Northeast at the end of the month, now has a warm vs cool boundary becoming established from the Middle Atlantic states to the central Plains. Such a setup would pave the way for a series of waves to move eastward along the frontal zone to cause episodes of rain. We'll just watch the situation for now.