|Dew Point:||34.0°F (1.1°C)|
|Sea Level Pressure:||30.16" (1021.2 mb)|
Hi 55 °F
Hi 66 °F
Hi 68 °F
Hi 67 °F
Mostly cloudy, with a low around 37. East wind 6 to 8 mph becoming southeast after midnight.
Mostly cloudy, with a high near 55. South wind 8 to 11 mph.
A slight chance of showers after 1am. Mostly cloudy, with a low around 45. Southwest wind 9 to 13 mph. Chance of precipitation is 20%.
A slight chance of showers before 1pm. Partly sunny, with a high near 66. West wind 6 to 8 mph. Chance of precipitation is 20%.
Partly cloudy, with a low around 51. Southwest wind around 7 mph.
A chance of rain after 1pm. Mostly cloudy, with a high near 68. Chance of precipitation is 30%.
A chance of rain. Mostly cloudy, with a low around 51. Chance of precipitation is 30%.
Partly sunny, with a high near 67.
A chance of showers. Mostly cloudy, with a low around 51. Chance of precipitation is 30%.
Mon Feb 20 2017
SYNOPSIS... High pressure will build overhead through tonight. Cooler air will seep south tonight into Tuesday. A weak disturbance will cross the area Tuesday night into Wednesday. High pressure will be located off the southeast coast of the United States Thursday through Friday. A cold front will pass through the area during the weekend.
NEAR TERM /THROUGH TUESDAY/... Upper-level ridge will build overhead through tonight while surface high pressure builds into New England. The surface ridge axis associated with the high will build over our area during this time. An easterly flow around the high will usher in cooler air compared to recent night. In fact...some areas may decouple overnight and radiational cooling may lead to chilly conditions...especially over northern Maryland. Min temps will range from the lower 30s in northern Maryland to the upper 30s and lower 40s in central Virginia.
High clouds will gradually increase as they rotate around the periphery of the upper-level ridge. A broken deck of lower clouds are possible overnight across the Shenandoah Valley into the Potomac Highlands due to light overrunning of the cooler air in place. However...no precipitation is expected.
The surface high will move off the New England coast Tuesday...but it will continue to wedge into the Mid-Atlantic. The upper-level ridge will also gradually move off to the east. An onshore flow around the high will cause cooler conditions compared to recent days...but max temps will still be above climo. An upper-level disturbance will approach from the west...bringing some clouds to the area but it should remain dry.
SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/... An upper-level disturbance associated with the northern stream of the jet will pass through our area Tuesday night into Wednesday...but it will be weakening as it moves through. Cutoff low pressure will develop in the southern stream of the jet...but that should remain well off to our south. A couple showers are possible Tuesday night into Wednesday...but with our area split between the northern and southern stream of the jet most areas may end up dry. The best chance for showers will be in the Allegheny Highlands due to an upslope component to the low-level flow.
High pressure will build offshore for Wednesday and Wednesday night...allowing for unusually warm conditions to return. Max temps Wednesday will once again be well into the 60s and 70s.
LONG TERM /THURSDAY THROUGH MONDAY/... Dry conditions expected for Thursday with southerly flow over our region and high temperatures in the 60s and low 70s. A frontal boundary will be approaching the region from the north allowing for some showers Thursday afternoon into Thursday night. Warm air advection continues Friday into Friday night with an increase in PoPs as cold front approaches from the west.
Deep low moves across the Great Lakes and a cold front moves across the Mid-Atlantic on Saturday... showers and thunderstorms likely. Dry conditions return Sunday into Monday as high pressure builds behind the front... high temperatures will be in the 50s and 60s, and in the 40s and 50s at higher elevations.