**Note: A new member--John Yarchoan--has joined DCweather.com and will add posts from time to time. We are also planning on adding a "weather wars" section in which we both battle over temperatures and weather forecasts**An offshore closed low seen on visable satellite (right) will keep the D.C. metro area unsettled for at least the first part of the work week. While we are not talking about a washout, scattered showers and thunderstorms are possible on Monday and even more likely on Tuesday and Wednesday. On a positive note, due to a lack in upper level winds, any shower or storm that may pop up in the afternoon hours has the potential of dropping a solid quarter to half an inch of rain, and thus may help us make a dent into the rainfall deficit. Also, temperatures will strugle to get out of the 70s for much of the week.
The closed low seen off the coast of Cape Cod (above)
The problem can be more clearly identified if we take a look at the 500 mb chart (left). A small disturbance which is what is left from the severe thunderstorm outbreak across the east on Friday is being forced between the troph from the closed low and a developing ridge across the deep south. When this happens, unsettled weather often takes control. The pattern will stay in place at least until Wednesday because as the disturbance drifts south, it will drag the closed low with it.
This can best be seen on the 500 mb chart
for Wednesday. In this frame, the disturbance as strengthened and drifted south to a position around Mobile, AL. As it has done so, it has forced the closed low south and west, thus continuing to give us unsettled weather.500 mb chart for Monday (top) and Wednesday
(bottom) showing the closed low across the
Northeast and a weak disturbance drift from
the Ohio River Valley to the deep south .
Images courtesy of Unisys Weather and NOAA
for this post
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