Area Forecast Discussion
Issued by NWS Sterling, VA
Issued by NWS Sterling, VA
510 FXUS61 KLWX 261755 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 155 PM EDT Fri Jul 26 2024 .SYNOPSIS... A cold front will move south of the area later today. Weak high pressure will build to our north today and Saturday, before becoming established offshore early next week. Precipitation chances return by mid to late next week. && .NEAR TERM /THROUGH TONIGHT/... A cold front that brought showers and thunderstorms yesterday is continuing to move further south of the area early this afternoon. Earlier thicker clouds have began to slowly dissipate from north to south, with some mid to high-level clouds lingering across central VA. Cannot rule out an isolated shower or thunderstorm across portions of central VA later today given the slowness of the progression of the weak cold front. This may allow for some low-level moisture to stick around before moving further south. Afternoon highs will top out in the mid to maybe even some upper 80s across the lower elevations. Overnight lows will drop down into the low to mid 60s for most areas aside from the Allegheny Front where mid 50s may be possible given the weak flow aloft. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... High pressure will dominate the area this weekend. This will allow for mostly sunny skies and lower humidity to persist through Sunday. Air temperatures will still be slightly above normal with low 90s expected across the lower elevations. Winds will remain light and variable as the high lingers around the region. Overnight lows will be in the low to mid 60s Saturday night before increasing slightly for Sunday night as a warmer, moist airmass moves in for the start of the workweek. Cannot rule out a stray shower across the far southwest areas by late Sunday night into early Monday morning. && .LONG TERM /MONDAY THROUGH THURSDAY/... By Monday, upper troughing will move into the Upper Midwest, while a cutoff upper low circulates off the Mid-Atlantic/southern New England coastline. Over time, the trough over the center of the country will slowly translate eastward. Induced southerly flow over the upper low`s circulation will draw it north or northwestward toward the Northeast US, but models differ significantly with respect to its exact placement by Tuesday. The cutoff low should depart well off to our northeast by Wednesday, but weak upper level troughing should remain overhead through Wednesday and Thursday. At the surface, high pressure will remain in place offshore, maintaining southerly flow locally. Continued southerly flow will lead to increasing low-level moisture. Much of Monday should remain dry, with just low end chances for showers and thunderstorms, especially to the west of the Blue Ridge. Chances for diurnal showers and thunderstorms will increase for Tuesday through Thursday as low-level moisture increases and the upper trough approaches from the west. Temperatures should stay within a few degrees of seasonal normals, with highs mostly in the upper 80s and lower 90s. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... Winds have diminished early this afternoon with an occasional gust to 10 knots possible through the remainder of the day. KCHO will have the only real chance for an isolated shower or thunderstorm later this afternoon/evening. Light winds and VFR conditions are expected for the weekend with high pressure dominating the Mid-Atlantic. Prevailing VFR conditions and southerly winds are expected on both Monday and Tuesday. Thunderstorms may lead to temporary drops to sub- VFR conditions on Tuesday afternoon. && .MARINE... Winds will continue to be light and variable throughout the afternoon and evening today and continue through much of the weekend as a result of high pressure over the waters. Cannot rule out an occasional gust to 10-15 knots during the afternoon and evening hours. Winds may near low-end SCA levels in channeled southerly flow on both Monday and Tuesday afternoon. && .TIDES/COASTAL FLOODING... Weak return flow as high pressure lingers to the north today into the weekend will allow for some of the more sensitive tidal locations like Annapolis to reach Action Stage today and Saturday and maybe even touching Minor Flood Stage by Sunday`s high tide cycle. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...None. && $$ SYNOPSIS...LFR/ADM NEAR TERM...ADM SHORT TERM...ADM LONG TERM...KJP AVIATION...KJP/ADM MARINE...KJP/ADM TIDES/COASTAL FLOODING...LWX