190 FXUS61 KLWX 260727 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 327 AM EDT Sat Jul 26 2025 .SYNOPSIS... A weak frontal boundary will drop into the region today and linger through early next week before eventually fizzling out. A stronger cold front will push through during the middle of the next week, leading to a more substantial air mass change towards the end of the week into next weekend. && .NEAR TERM /THROUGH TONIGHT/... Today will start fairly quiet and humid with temperatures a few degrees cooler than we saw on Friday and heat indices a couple of degrees cooler than Friday as well. Heat indices may get close to advisory criteria in eastern parts of the Virginia Piedmont and eastern Virginia, particularly near the Fredericksburg area. For now, have held off on Heat Advisories at this time, but it will be very close. Main question was how cloudcover will impact temperatures during peak heating. As always with this time of year, even though we may not quite hit Advisory criteria, it will still be very hot, so take plenty of breaks and stay cool and hydrated today. Additionally, chances for showers and thunderstorms will increase today as a weak frontal boundary drops south into the region. Scattered heavy convection in the form of showers and strong to possibly severe thunderstorms are anticipated to develop this afternoon/evening as a result of this boundary colliding with very warm and humid air that remain entrenched across our area. While any given location could encounter showers or a thunderstorm today, a few isolated spots could receive 1 to 2 inches of rain in a short period of time, frequent lightning, wind gusts to 50 mph or all of the above. SPC has much of our region in a Marginal Risk for Severe Thunderstorms on Saturday into Saturday night. High temperatures lower 90s for most, with heat indices in the low 100s. Going into this evening, the lingering boundary and continued humidity will likely allow for some showers and storms to continue well into the overnight hours. Low temperatures will only drop down into the mid 70s overnight. As any showers do come to an end, fog looks likely to develop, especially in areas that get rain during the day. Current model guidance is really hitting central VA, especially east of the Blue Ridge. There is the potential that some patchy Dense Fog could develop into Sunday morning in those areas. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... As we get into the day Sunday into Sunday night, a more active shower and thunderstorm day is anticipated for most as a more potent piece of shortwave energy pushes through the region from the northwest. The aforementioned frontal boundary remains stalled nearby and continues to interact with a hot and humid air mass. There is a possibility that thunderstorms could become strong to severe once again as they generate in or around this heat and humidity. The main threats will be torrential rainfall rates, frequent cloud-to-ground lightning, and damaging wind gusts. The front may dissipate to the south by Monday, allowing weak surface high pressure to build across the area. Forcing will be nebulous, so thunderstorm chances appear to be relatively lower and focused on the diurnal terrain circulations. However, we will be in northwest flow aloft around the mid-CONUS ridge, so will have to be mindful of any remnant MCVs that could provide an extra source of lift. && .LONG TERM /TUESDAY THROUGH FRIDAY/... Warm and humid conditions continue through midweek as surface high pressure remains over the forecast area. A cold front will slowly approach from the northwest through Wednesday, before moving through the area on Thursday. This will yield daily afternoon shower and thunderstorm chances Tuesday through Thursday. As the cold front settles over the Carolinas, precipitation chances will linger in the southern portions of the forecast area Friday. Conditions dry out in the northern half of the forecast area Friday afternoon and through the overnight as surface high pressure builds in from the Great Lakes. In addition to the daily thunderstorm chances, the main story of the long term period will be the summertime heat. High temperatures Tuesday and Wednesday will be in the 90s for most with higher elevations staying in the upper 80s. Dewpoint temperatures in the low/mid 70s will yield heat indices of 100-105 for most of the lower elevations. Heat indices could reach 110 east of the Blue Ridge, mainly on Tuesday afternoon. High temperatures cool on Thursday in the wake of a cold front, with highs in the 80s (70s mtns) expected. Heat indices fall below criteria level, with values in the 80s and 90s. High temperatures continue to cool on Friday with highs in the 70s to low 80s across the area. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... Showers and thunderstorms are expected to develop this afternoon through this evening as a front drops through the region amidst very warm and humid air. While the overall condition today is expected to be VFR, could see some reductions if storms hit a terminal directly. Torrential rainfall (1-2"/hour), frequent lightning, and wind gusts up to 50 mph will all be threat this afternoon. These will be scattered in nature though, so exact impacts on any one given terminal are still somewhat uncertain, so kept the PROB30 groups in. For MRB, certainty is higher though, so did a prevailing group with a tempo for more intense storms. later TAF AMDs may be able to hone in on the threat a little better. IFR CIGS seem likely tonight across much of the region as low- level moisture increases and becomes trapped beneath the inversion. Could even see some dense fog in areas, but not sure if that will impact any of the terminals at this time. More showers and gusty thunderstorms are expected Sunday as a more potent piece of upper-level energy traverses the region. Expect the same threats as we see today, but with a bit more certainty. Expect this activity to show up with the afternoon TAF package. On Monday, the upper ridge begins to build back overhead, which could lead to a decrease in thunderstorm coverage. However, there does appear to be a disturbance moving around the eastern edge of this ridge, which could bring storms to MRB and CHO. Flight restrictions are possible Tuesday and Wednesday afternoon due to shower and thunderstorm chances. Otherwise, prevailing VFR conditions are expected across all terminals. Northwesterly winds blow 5 to 10 knots each afternoon before becoming light and variable overnight. && .MARINE... The only marine hazards that are anticipated will be Special Marine Warnings that could be issued pending heavy showers and strong to severe thunderstorms this afternoon and evening. This will be a threat again on Sunday afternoon and evening with a more potent upper-level disturbance traversing the region and interacting with the stalled frontal boundary. Monday may remain mostly dry over the waters as the upper ridge begins to build back into the region. There is a slight chance that a disturbance around the eastern periphery of the ridge moves over the water, but keeping chances below 30 percent for now, as this activity should remain over the higher elevations. Daily shower and thunderstorm chances may lead to hazardous conditions over the waters Tuesday and Wednesday afternoon. SMWs may be needed if storms become strong to severe. Otherwise, winds remain below SCA criteria both days, blowing out of the northwest both days. && .TIDES/COASTAL FLOODING... Tides will be on the gradual rise throughout the weekend and could reach Minor Flooding at the sensitive sites like Annapolis by Sunday night into early Monday. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...None. && $$ SYNOPSIS...CJL NEAR TERM...CJL SHORT TERM...LFR/CJL LONG TERM...AVS AVIATION...AVS/CJL MARINE...AVS/CJL TIDES/COASTAL FLOODING...LWX