Area Forecast Discussion
Issued by NWS Sterling, VA

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624 FXUS61 KLWX 300036 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 836 PM EDT Mon Aug 29 2016 .SYNOPSIS...
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High pressure will remain over the Mid Atlantic will move offshore late Tuesday. A cold front will move through the area Wednesday night. High pressure returns for late in the week.
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&& .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
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High pressure remains across the northeastern United States. There wasn`t much thunderstorm activity to begin with, mainly confined to the spine of the Appalachians west of Highland and Pendleton Counties, but the loss of daytime heating suggests that the rest of the night will be dry across the area. (The 00z LWX RAOB depicts weak CINH in both the surface and mean layers.) Drier air (dewpoints below 60F) have infiltrated the northern parts of the area. Fog development will be real sparce, if at all. Going temperature forecast in line with latest LAMP. At this juncture will not be making any adjustments.
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&& .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... Models suggesting a weak nearly stationary boundary remains in placed over portions of the area Tuesday as near zonal flow minimizes any further southern progression of the front. Another warm day with afternoon convection possible, especially out west over the higher elevations. By Wednesday, a cold front will slowly approach from the west, eventually passing through Wednesday night. This will bring another chance for showers and thunderstorms, though now possible across the entire CWA. The above normal temps will continue through this time period. && .LONG TERM /THURSDAY THROUGH MONDAY/... The cold front dropping south of the area by Thursday morning is expected to push Tropical Depression 8 out to sea, avoiding any significant impacts to the area. For the latest of TD 8, please see the latest forecasts from the National Hurricane Center. An unusually strong surface high will build into the region from the north behind the front and persist through the end of the week bringing slightly below normal temperatures and a much drier airmass. Tropical Depression 9 (or whatever becomes of it) is then forecast to pass well south and east of the area over the weekend, again preventing significant impacts. However, its future is much less certain given the time range. Again, for the latest forecasts on TD 9, please see products from the National Hurricane Center. A gradual warming trend is then forecast by the end of the weekend into early next week as high pressure moves offshore and establishes itself over the northwestern Atlantic. && .AVIATION /01Z TUESDAY THROUGH SATURDAY/... Generally VFR conditions through the end of the week. Only restrictions would come in some patchy fog at night/early morning and any scattered showers/thunderstorms late Wednesday and Thursday. Winds through the period 10 knots or less, && .MARINE...
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Winds expected to remain below SCA values today through Wednesday. Latest mesoscale guidance suggests that there may be a surge of winds down the Bay late tonight into early Tuesday morning. In light of dewpoints across Pennslyvania, that remains possible. Will be capping these winds at 15 kt though. Northerly channeling behind a departing cold front may result in Small Craft Advisory level winds Thursday into Thursday night, gradually subsiding into Friday as high pressure builds into the area.
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&& .TIDES/COASTAL FLOODING...
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Water levels departures are fairly static just under a half-foot above astronomical normals. These elevated water levels are forecasted to remain in place through at least Wednesday night. If tidal anomalies reach a half to three-quarters of a foot above normal, minor coastal flooding would be possible nightly (early morning, actually) at Annapolis. It will be a real close call, but based on trends this evening do not trust it will happen tonight; thus no Advisory...yet.
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&& .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...None. && $$ SYNOPSIS...Sears/HTS NEAR TERM...HTS SHORT TERM...Sears LONG TERM...DFH AVIATION...Sears/HTS/DFH MARINE...Sears/HTS/DFH TIDES/COASTAL FLOODING...HTS

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