Area Forecast Discussion
Issued by NWS Sterling, VA

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867 FXUS61 KLWX 071425 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 1025 AM EDT Sun Jun 7 2026 .WHAT HAS CHANGED...
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No changes to the forecast. A cold front, currently bisecting the region into a northern half and southern half, will move south of the region later this afternoon. A few storms are still possible along the I-64 corridor. High pressure will bring cooler and drier conditions to the region tonight through Tuesday before hot and humid conditions return later this week along with thunderstorm chances.
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&& .KEY MESSAGES...
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- 1)) A cold front descends across the area through tonight. A couple of showers and a thunderstorm or two could develop along the I-64 corridor. - 2) Briefly cooler conditions develop in onshore flow Monday into Tuesday. - 3) Heat, humidity, and thunderstorm chances return mid to late week, with heat index values possibly approaching 100.
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&& .DISCUSSION...
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KEY MESSAGE 1...A cold front descends across the area through tonight. A couple of showers and a thunderstorm or two could develop along the I-64 corridor. A surface cold front is bisecting our region into a northern and southern half. Currently, the radar is quiet. However; with additional heating this afternoon, we could see showers and a few thunderstorms develop in parts of the central Shenandoah Valley, across the Virginia Piedmont, and far southern Maryland. The I-64 corridor could be focal zone for a strong thunderstorm or two given the proximity of the front. The main threats will be 55-65 mph wind gusts and small hail in the strongest thunderstorms. Timing of this convection still appears to be between 11am and 2pm. Cooler nighttime lows in the 60s (50s mountains) are expected with lower humidity tonight into early Monday morning. KEY MESSAGE 2...Briefly cooler conditions develop in onshore flow Monday into Tuesday. A rather stout area of surface high pressure is expected to build from the Northeast into the Mid-Atlantic early this week in the wake of the front. This may actually push the front as far south as Florida by mid week. Locally, this area of high pressure results in cooler onshore flow (relatively speaking, though highs still look to be in the 80s). Despite the onshore flow, the origin of the high pressure is dry so dew points also look to be lower. The ridge begins to break down on Tuesday as high pressure nudges to the east. A rogue shower could approach the central Appalachians Monday afternoon, but better chances for a shower or thunderstorm exist over the Appalachians Tuesday afternoon. KEY MESSAGE 3...Heat, humidity, and thunderstorm chances return mid to late week, with heat index values possibly approaching 100. As the aforementioned area of high pressure slides offshore, strong ridging aloft will build over the East Coast. This will slide a dome of higher heat from the central CONUS into the local area the second half of the week. Recent bouts of heat have been somewhat dry/continental in nature, but this next wave looks to have some more moist/tropical component to it. The higher humidity may lend toward a more notable heat index increase. I will caution that the NBM can sometimes bias-correct too high for dew points in the longer term depending on the setup (probably due to mesonets that read too high during these setups), but even lower to mid 90s air temps with mid to upper 60s dew points would result in 95-100 F heat index values during the afternoon hours Thursday/Friday. With the increasing heat and humidity comes increasing shower and thunderstorm chances. With ridging nearby, flow aloft won`t be particularly strong. But, the moderate to strongly unstable airmass could still result in isolated/localized but still potent storms capable of gusty winds. A more appreciable front/trough may drift toward the area by next weekend, though ensemble spread and therefore forecast uncertainty increases by this time.
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&& .AVIATION /14Z SUNDAY THROUGH THURSDAY/...
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VFR with mid/high clouds are expected for another hour or two with gradual clearing this afternoon as a cold front slides to the south. A shower or two can`t be ruled out just about anywhere into the early afternoon, but there is a slightly higher chance near the CHO terminal. Winds W/NW winds gust 15-20 kts into early this evening before becoming light N/NE tonight. NE to E flow is expected Monday into Monday night, becoming S Tuesday through Wednesday then SW/W Thursday. VFR conditions are anticipated with winds AOB 15 kts most of the time, though some daytime gusts to near 20 kts can`t be ruled out. Despite the onshore flow Monday, the origin (from a dry high) likely precludes more widespread lower ceiling potential. Shower and thunderstorm chances increase the second half of the week in typical pop up summer fashion.
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&& .MARINE...
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West to northwest flow will increase over waterways and along the western shore of the Chesapeake Bay through early this evening as a cold front slides south and diurnal mixing increases. Hot air over cooler water may preclude gustiness over wider/eastern waterways. A shower or thunderstorm could approach the waters near southern Maryland this afternoon. Light north winds are expected tonight, turning northeast to east on Monday. An increase in onshore flow is expected Monday which will likely warrant additional SCAs. Dry weather is expected during this time. As high pressure drifts offshore Tuesday through Thursday, southerly flow/channeling effects may prompt SCAs at times. Winds may become more southwest/west Thursday. Shower and thunderstorm chances increase the second half of the week.
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&& .LWX WATCHES/WARNINGS/ADVISORIES...
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DC...None. MD...Small Craft Advisory until 8 PM EDT this evening for MDZ008. VA...None. WV...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ530>533-535-536-538-542.
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&& $$ DISCUSSION...KLW/DHOF AVIATION...KLW/DHOF MARINE...KLW/DHOF