Area Forecast Discussion
Issued by NWS Sterling, VA

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401 FXUS61 KLWX 101848 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 248 PM EDT Fri May 10 2024 .SYNOPSIS...
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Shower chances continue today as a stalled frontal boundary sits south of the region. Additional shower and thunderstorm chances are likely Saturday and Sunday as another front passes through. Drier conditions return with brief high pressure Monday into Tuesday. High pressure pushes offshore by the middle of next week leading to a return of warmer temperatures and unsettled conditions.
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&& .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
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A weak trough over the area, combined with a slow moving backdoor cold front and CAD wedge continue to produce widespread light rain and showers across the area. Areas north of I-66/US-48 are starting to transition from stratiform light rain to more convective light showers. Expect this to continue through the evening, before diminishing overnight. To the south of I-66 where there has been more instability built up through the afternoon, scattered showers and a few thunderstorms are ongoing. This activity will push to the south/east through sunset. Additional lower clouds build in this evening, then conditions begin to dry out for most overnight. Noticeably cooler conditions tonight as lows settle in the 40s.
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&& .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
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A second upper trough and associated surface cold front look to cross the area Saturday afternoon into Saturday night, bringing widespread showers and perhaps a few thunderstorms. The system moves east of the area Sunday morning, though some residual moisture on the backside of the broad low could bring some on-and-off showers to the eastern half of the area through Sunday afternoon. Conditions dry out Sunday evening as high pressure builds in. Cooler temperatures through the weekend. Highs in the 60s each day, with some low 70s possible in Central VA Sunday afternoon. Overnight lows mostly in the 40s.
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&& .LONG TERM /MONDAY THROUGH FRIDAY/...
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Monday looks to be our driest day of the next 7 days with mid level ridging overhead and surface high pressure sitting just to the south of the region. This will yield a seasonable Spring day with high temperatures in the mid to upper 70s and overnight lows in the 50s. Unfortunately, the dry time will be brief as an upper trough develops in the lee of the Rockies, and deepens as it tracks eastward from the mid-Mississippi River Valley during the middle part of workweek. Meanwhile, high pressure will shift off the VA/NC coast Tuesday into Wednesday allowing for south to southeasterly return flow to ensue. This will allow Atlantic and eventually Gulf of Mexico moisture to increase across the region yielding daily isolated to scattered chances for showers and thunderstorms. Uncertainty remains in the placement and timing of the heaviest precipitation with a focus midweek (late Tuesday into Wednesday). This is due largely in part to a warm frontal boundary that will be lifting northward into the region. The severe weather threat appears to be minimal with richer moisture suppressed toward the Gulf Coast. Locally heavy rainfall is possible especially during the midweek timeframe due to increasing moisture and the placement of a warm front draped nearby. High temperatures will remain at or slightly below normal midweek. Expect highs in the low to mid 70s Wednesday and mid to upper 70s Thursday. Lows will fall into the mid to upper 50s. Low pressure and it`s resulting trough depart offshore Thursday into Friday. A cold front will quickly follow bringing in drier air as high pressure builds over eastern Canada. The dry time once again will be short lived as another trough and area of low pressure approach from the Ohio River Valley.
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&& .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
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MVFR to IFR conditions in light rain continue to impact most terminals through late this evening. Showers around CHO this afternoon should dissipate after sunset, then lower CIGs to around IFR could build back in for the evening and first half of tonight. Conditions begin to improve late tonight. VFR conditions are likely for most of the weekend, though abundant cloud cover is expected through at least Sunday morning. Showers and perhaps a few thunderstorms moving through Saturday evening into Saturday night could produce some sub-VFR conditions. Light north winds Saturday morning quickly shift to south by late morning. A cold front sweeps through early Sunday, with winds shifting to northwest behind the front. VFR conditions are expected with high pressure nearby. Sub VFR ceilings along with a showers and a few thunderstorms are possible Tuesday and Wednesday as an area of low pressure and front push into the region. Shower and thunderstorm chances look to linger Thursday with high pressure briefly returning Friday. South to southwesterly winds are expected Monday before switching to the south and southeast Tuesday and Wednesday. Gusts of 15 to 20 kts can be expected each afternoon.
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&& .MARINE...
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SCA winds continue at times across all the waters through tonight, though the time for strongest winds looks to be this evening into early tonight. Winds quickly diminish overnight, except for the southern Chesapeake Bay where gusty winds could last through early Saturday morning. Rain showers and thunderstorms could impact the waters again Saturday evening into Saturday night, though not looking at any strong storms at this point. Winds look to remain below SCA levels through the weekend. However, will need to keep an eye for Sunday afternoon as northwest winds increase behind a cold front that crosses the local waters Sunday morning. SCA conditions will likely continue Monday, Tuesday, and Wednesday as low pressure approaches from the south and high pressure pushes offshore. South to southeasterly winds will gusts up to 20 kts each day with the potential for a few thunderstorms on both Tuesday and Wednesday afternoon/evening.
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&& .TIDES/COASTAL FLOODING...
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Tidal anomalies remain elevated through tonight, then drop off by Sunday when offshore northwest flow kicks in across the area. Could see additional minor coastal flooding during high tide this evening.
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&& .LWX WATCHES/WARNINGS/ADVISORIES...
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DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory until 4 AM EDT Saturday for ANZ530>533- 538>541. Small Craft Advisory until 8 AM EDT Saturday for ANZ534-537- 542-543. Small Craft Advisory until midnight EDT tonight for ANZ535-536.
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&& $$ SYNOPSIS...EST NEAR TERM...KRR SHORT TERM...KRR LONG TERM...EST AVIATION...KRR/EST MARINE...KRR/EST TIDES/COASTAL FLOODING...KRR