Area Forecast Discussion
Issued by NWS Sterling, VA

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277 FXUS61 KLWX 221429 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 1029 AM EDT Sat Oct 22 2016 .SYNOPSIS... AN upper trough will cross the region this morning. Surface high pressure will be moving in as low pressure strengthens as it moves away to the NE. The result will be gusty winds. A reinforcing cold front moves through Monday with cool high pressure to follow for mid week. A weak warm front nearing the area may bring some showers Thursday. && .NEAR TERM /THROUGH TONIGHT/... Upper level trough axis pivoting eastward with last of the showers exiting the Bay. Some upslope precipitation continues, with snow observed across the ridge at Canaan Valley. In between, clearing is taking place, which is allowing mixing to increase. Numerous reports of wind gusts 30-40 MPH are currently occurring. The gradient actually decreases through the afternoon, which means the peak winds will likely occur through noon. The peak gust at Wintergreen (WNTRE) was 49 kt at 7 AM. Will likely be able to let the advisory expire as winds aloft decrease slightly. However, must consider that winds above 3kft may once again increase tonight, although CAA pattern will be ceasing, which may limit downward transport. At lower elevations, the winds will decrease this evening, but remain gusty through the night outside of sheltered valleys. Temperatures are largely following the forecast curve, so minimal adjustments are needed. After highs in the 50s to perhaps lower 60s, temperatures will fall into the 40s tonight (excluding the colder higher elevations). && .SHORT TERM /SUNDAY THROUGH MONDAY/... High pressure will produce a pleasant fall day for Sunday. A reinforcing cold front moves through on Monday with cool temps for midweek. No precip expected with the front however. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... High pressure will settle over the Mid Atlantic states Tuesday into Wednesday, providing sunny skies and cool temperatures. Its still looking like a good radiational cooling setup for Tuesday night, making it the most obvious choice for upcoming frost potential. The forecast for the end of the week not clear-cut at all, as GFS/ECMWF depicting distinctly different solutions. Am not certain either is all that likely. Even the various GEFS members in complete disarray. Will be maintaining some semblance of continuity in that there will be POPs at the end of the forecast from a transitory shortwave and surface reflection. Fairly low confidence at this time as to how strong this cold front will be. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... Gusty NW winds to contend with this morning (35+ kt possible)...gradually diminishing this afternoon. Gusts up to 25 kt continue through Sunday. Otherwise VFR conditions through the weekend and early week. Aside from patchy early morning valley fog, VFR Tuesday- Wednesday under high pressure. && .MARINE... Gale warnings for the waters today for NW winds. A few observed reports up to 40 kt, although should see some gradual decreasing this afternoon. Small Craft Advisory level winds will persist for most of the waters into Tuesday morning before high pressure builds across the waters. Headlines will be adjusted by this afternoon. Otherwise, diminishing north winds Tuesday becoming light Wednesday. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...Wind Advisory until noon EDT today for VAZ025>027-029-503-504- 507-508. WV...Wind Advisory until noon EDT today for WVZ055-501-502-505-506. MARINE...Small Craft Advisory from 2 AM to 8 PM EDT Sunday for ANZ531>534-539>541-543. Gale Warning until 2 AM EDT Sunday for ANZ531>534-539>541-543. Gale Warning until 6 PM EDT this evening for ANZ530-535>538- 542. && $$ SYNOPSIS...CAS NEAR TERM...ADS SHORT TERM...CAS LONG TERM...HTS AVIATION...ADS/CAS/HTS MARINE...ADS/CAS/HTS is the U.S. government's official web portal to all federal, state and local government web resources and services.