Area Forecast Discussion
Issued by NWS Sterling, VA

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390 FXUS61 KLWX 070846 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 346 AM EST Sat Mar 7 2026 .WHAT HAS CHANGED...
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No significant changes to the forecast this morning, but added a new key point regarding a strong frontal passage by the middle of next week.
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&& .KEY MESSAGES...
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- 1) Rain chances continue through Sunday, as multiple fronts impact the region. This will be followed by a warming trend into next week. - 2) A strong cold front is likely to push through the region midweek, bringing back chances for significant rain followed by a sharp drop in temperatures.
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&& .DISCUSSION...
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KEY MESSAGE 1...Rain chances continue through Sunday, as multiple fronts impact the region. This will be followed by a warming trend into next week. Onshore flow has continued to funnel in a potent marine layer this morning, with some very low stratus and even some fog/mist. This is going to take some time to scour out this morning, but do expect it to occur a bit quicker than previous days. This is because high pressure will shift further east today, while a potent shortwave and associated area of low pressure rapidly track northeastward from the Upper Midwest/Great Lakes toward Quebec. As this occurs, winds at the surface will turn southerly and winds aloft will increase out of the southwest. This will likely allow the cold air damming wedge to finally break to the east of the Blue Ridge by the afternoon and evening hours. As a result, temperatures are forecast to be a good bit warmer today further northeast, with most of the forecast area (with the exception being Northeast Maryland) climbing into the 60s and 70s by mid-late afternoon. The combination of deeper moisture advecting into the area in southerly flow (dewpoints reaching into the upper 50s to lower 60s), daytime heating, and glancing ascent as the shortwave passes to our north and west will enable showers and thunderstorms to develop by later this afternoon into the evening. This will come in two rounds, with the first round forming within a surface trough just to the east of the Alleghenies during the mid-late afternoon hours. Model soundings show a fair amount of dry air in place aloft, and large scale forcing for ascent won`t be overly strong, so areal coverage with this first round of storms is only expected to be isolated to scattered in nature. If storms do become well established, the background environment will have enough instability (around 1000 J/kg of MLCAPE) and shear (around 40 knots in the 0-6 km layer) to promote updraft rotation. Isolated instances of damaging winds or hail may be possible with these storms as they move eastward from the Potomac Highlands toward the I-81 corridor and then the Blue Ridge/Catoctins during the mid-late afternoon hours. Conditions will likely remain dry to the east of US-15 during the daylight hours. A second round of pre-existing storms will approach from the Ohio Valley, reaching the Allegheny Front around sunset. This round of storms could be well organized into a squall line, and may potentially be quite intense. With the loss of daytime heating, the trend will likely be downward with the strength of this activity as it moves into our area, but damaging winds may still be possible, especially along and west of the Allegheny Front. Large scale forcing for ascent may enable these storms to hold together in a weakened form as they move eastward across the forecast area during the first half of the night. SPC has Garrett County in Slight Risk for severe thunderstorms, with locations further east to about US-15 in a Marginal Risk. The actual surface cold front will move through the area late tonight into Sunday morning. There is still some disagreement amongst guidance regarding the timing of the frontal passage, and how much daytime heating will occur ahead of the front during the day on Sunday. We`ll likely have some lingering cloud cover and showers during the morning ahead of the front. Depending on how fast the front progresses, some daytime heating could occur ahead of the front across southern Maryland, potentially leading to the development of a few thunderstorms. Clearing is expected from northwest to southeast during the afternoon and evening hours as drier air starts to work in behind the front. High temperatures on Sunday will be in the 60s and 70s for most, with 50s in the mountains. Temperatures mainly in the 70s and 80s Monday and Tuesday under partly to mostly sunny skies as high pressure builds back into the region. KEY MESSAGE 2...A strong cold front is likely to push through the region midweek, bringing back chances for significant rain followed by a sharp drop in temperatures. Relatively calm and sunny conditions are likely to continue on Tuesday, before zonal flow aloft starts to transition to an upper trough centered over the Northeast on Wednesday. This will result in a strong cold front set to push through the East Coast over the Wednesday/Thursday timeframe, likely bringing significant rain to the region followed by a sharp drop in temperatures by the end of next week. The ECMWF and GFS are currently showing this temperature drop to start on Thursday night, and there are early signals showing lows to shift back to sub-freezing temps out over the mountains for a period as high pressure takes over towards the end of the week. Within the rest of the region, temps could drop to the 40s-50s on Thursday and Friday.
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&& .AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
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LIFR CIGs are being observed at all terminals at this time, and that will continue through this morning for all. Patchy dense fog is still possible, but likely closer to sunrise, and very brief. Either way, some VSBY reductions likely during that period, and CIGs will not improve until later. Gradual improvement is expected through the day, with conditions clearing out first at CHO, and last at MTN. CIGs will likely climb a few hours quicker than yesterday as winds turn out of the south and pick up to around 15 to 20 knots. Showers and thunderstorms will approach from the west this evening, but will likely be weakening as they do so. For now, left the mention out of any TAFs, but will continue to monitor as the day moves on. A cold front will move through on Sunday, leading to a return to VFR conditions and a shift to westerly winds. Prevailing VFR conditions across terminals on Monday and Tuesday, followed by periods of lowered CIGs and VSBYs associated with a strong cold front impacting the region between late Wednesday and Thursday. Southerly winds likely to shift northwesterly on Wednesday, with gusts up to 20 knots possible.
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&& .MARINE...
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Winds will turn out of the south today, and remain sub-SCA in nature through much of the day. However, am expecting winds to pickup a bit during the afternoon/evening, with SCAs being issued as a result. Warm air moving over cooler waters will likely be a limiting factor to some extent, especially over the wider waters, but think there has been enough of a trend upwards to expect some solid 20 knot gusts. Winds drop below SCA criteria by Sunday morning and shift out of the west by Sunday afternoon as a cold front moves over the waters. No marine hazards Monday through Tuesday night. Winds generally south to southwest 5 to 10 knots. SCA conditions are possible on Wednesday, with gusts up to 20 knots throughout the bay currently forecasted associated with a strong cold front pushing through midweek. Winds may further strengthen on Thursday before gradually decreasing towards the end of the week.
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&& .LWX WATCHES/WARNINGS/ADVISORIES...
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DC...None. MD...Dense Fog Advisory until 10 AM EST this morning for MDZ501-510. VA...Dense Fog Advisory until 10 AM EST this morning for VAZ026>031. WV...Dense Fog Advisory until 10 AM EST this morning for WVZ050>053- 055-503-504. MARINE...Small Craft Advisory from 7 PM this evening to 5 AM EST Sunday for ANZ531-532-538>540. Small Craft Advisory from 7 PM this evening to 8 AM EST Sunday for ANZ533-534-537-541>543. Small Craft Advisory from 2 PM this afternoon to 5 AM EST Sunday for ANZ535-536.
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&& $$ DISCUSSION...CJL/KJP/SRT AVIATION...CJL/KJP/SRT MARINE...CJL/KJP/SRT