FXUS61 KLWX 080123 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 923 PM EDT Tue Jul 7 2026 .WHAT HAS CHANGED... The Flood Watch was cancelled as the flood threat has diminished across the area. Showers continue across portions of the area through late this evening. && .KEY MESSAGES... - 1) Another round of heavy showers and thunderstorms is expected through this evening. - 2) Daily shower and thunderstorm chances continue through the weekend. && .DISCUSSION... KEY MESSAGE 1...Another round of heavy showers and thunderstorms are expected this evening. As of 18Z/2PM EDT, showers and thunderstorms were steadily developing west of the Blue Ridge Mountains. Additional development looks probable into the central VA piedmont given towering cumulus along a stalled front. To the north, widespread stratus remains. Underneath mainly overcast skies, temperatures are gradually rising through the 70s (north) and 80s (south). The expectation is for the front to meander north to south, generally being repositioned by convective-scale processes and where cloud breaks occur. A weak wave of low pressure approaching western MD drifts east tonight, giving the front a reinforcing push to the south. A tropical air mass remains in place with precipitable water values staying in the 2 to 2.25 inch range. The tropospheric flow stays on the weaker side which favors slow and rather chaotic cell motions. Latest high-resolution models continue to focus for more concentrated convection along/west of US-15 until early evening, then north-central VA this evening. This generally marks where the Weather Prediction Center has a Slight Risk for flash flooding today. With heavy rainfall characterized by intense rainfall rates and a threat for repeat/training convection, Flood Watches remain in effect. The watch may need to be expanded into NoVA. The most vulnerable spots would be areas hit by recent heavy rainfall over the past couple of days, as well as urban areas or areas of complex terrain. River and stream levels began low due to ongoing drought conditions. However, these have risen in some areas recently which makes them more vulnerable to future flooding. On the severe weather side of the equation, moist profiles and a lack of steeper low-level lapse rates or shear should keep the severe weather threat low, though a couple storms may produce locally gusty winds in the I-64 corridor. By mid-week, the parent frontal zone is expected to reach the Carolinas while stretching back up into the central Appalachians. As an upstream shortwave trough continues to shear on its eastward approach, the residual energetics from this feature will keep convection in the forecast. Any severe threat appears minimal, but some non-zero flood threat persists given recent bouts of heavy rainfall mainly near the stalled front over west-central VA. Owing to mainly east to northeasterly surface winds, Wednesday will yield below average temperatures with highs in the upper 70s to mid 80s, with mid 60s to mid 70s for the mountains. KEY MESSAGE 2...Daily shower and thunderstorm chances continue through the weekend. A nearly zonal flow aloft is expected during this time while several upper-level disturbances pass through the area. A weak boundary overhead Wednesday will lift to the north as a warm front Thursday allowing for more warm and humid conditions that persist through the weekend. The lifting warm front could trigger thunderstorms mainly east of the Blue Ridge late Wednesday night into early Thursday morning. The combination of having the boundary overhead Wednesday along with the increase heat and humidity late in the week will cause daily shower/thunderstorm chances, with the highest probabilities for convection being in the afternoon and evening hours each day. The highest coverage of showers/t-storms may be Thursday where most guidance is showing a strong upper-level disturbance in the quasi-zonal flow aloft. Another weak boundary may move into the area during the weekend, bringing more unsettled conditions. High pressure will likely return briefly late in the weekend, then another vigorous shortwave may approach early next week. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Mainly MVFR conditions (in the form of lower CIGs) were being observed at the TAF sites as of 18Z/2PM EDT (though IAD was still having intermittent IFR CIGs). A gradual lifting and scattering of these clouds may result in a period of VFR late this afternoon into this evening. Thunderstorms were developing west of the Blue Ridge, with mid to late afternoon the most likely period for TS near MRB/CHO. This evening, as a ripple of low pressure glides along the stalled boundary over the area, TS may become possible in the metros. Confidence in coverage is low. Another round of low ceilings is expected tonight into Wednesday morning. Winds turn more easterly through the day with some diurnal showers and thunderstorms possible. Any stronger storm could yield brief sub-VFR conditions, though precip chances are much lower in the metros Wednesday and therefore not mentioned in the TAF at this time. VFR conditions are most likely for most of the time Thursday through Saturday, but a few showers and thunderstorms are possible each day, especially during the afternoon and evening hours. There may be a higher focus for strong storms Thursday. && .MARINE... Sub-advisory caliber winds are expected across the waters given weaker gradients through at least mid week. Any hazardous conditions are likely going to be tied to convection, lightning, and any accompanying gust fronts/outflows. Additional thunderstorm chances are maintained in the afternoon/evening forecast. Special Marine Warnings are looking less likely through Wednesday as most storms may stay west of the waters. Through mid-week, expect mainly east to northeasterly winds at or below 10 knots Southerly winds are expected Thursday and could briefly approach SCA levels. Some strong afternoon/evening storms are possible as a cold front approaches. A west to northwest flow is expected Friday into Saturday. The flow may turn onshore during each afternoon/evening. Winds should remain below SCA criteria most of the time, but a few showers and thunderstorms are possible each day, especially during the afternoon and evening. && .TIDES/COASTAL FLOODING... Light onshore (east to northeast flow) the next couple days followed by southerly flow will cause rising tides over the next couple of days. This will likely result in near minor flooding of vulnerable shoreline the second half of this week. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...None. && $$ DISCUSSION...AVS/BRO/DHOF AVIATION...AVS/BRO/DHOF MARINE...AVS/BRO/DHOF