318 FXUS61 KLWX 071412 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 1012 AM EDT Fri Oct 7 2022 .SYNOPSIS... A strong but moisture-starved cold front will cross the Mid- Atlantic this afternoon. Cold high pressure will follow for the weekend. A backdoor front will likely approach by Tuesday before dissipating. && .NEAR TERM /THROUGH TONIGHT/... A surface cold front will cross the Ohio Valley around midday and then proceed into the mid-Atlantic. This front will bring breezy and noticeably cooler conditions to the region late this afternoon and into much of the weekend. Moisture is limit so relying on an upslope component to the wind and the lift of the front, there will be a few showers in the mountains. A few of the convective models show some shower activity around the metro areas later this afternoon into early evening. The best opportunity for showers in the metro area would be between 5-11 PM. Temperatures will be mild with highs in the 70s. For areas east of the Blue Ridge, a few spots may even reach the 80 degree mark. Otherwise, the other story will be the breezy northwesterly winds behind the front. Gusts up to 25-30 mph are possible during the evening and into portions of the night. Cold advection continues into the overnight which will allow temperatures to fall. While most are in the 40s, some mid/upper 30s are expected across the higher terrain. Any freeze potential would be near the ridgetops, with frost production stunted by the continued winds. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... Previous discussion... The frontal system will have exited into the offshore waters by Saturday morning. Residual pressure gradients should keep wind fields up a bit through the afternoon hours. Some of the expected cooling will be offset by the downsloping flow. The 00Z NAM model sounding showed notable mixing up to 850-mb which would favor dry-adiabatic lapse rates. Forecast highs top out in the upper 50s to low 60s, with 40s across the mountain locales. Plenty of sunshine can be expected on Saturday with breezes dropping off into the evening and night. Upstream high pressure settles off to the south and west by Saturday night. However, its close proximity should allow winds to drop off, favoring a chilly night. The most likely regions for patchy frost would be along and west of the Blue Ridge and Catoctins. Some of the cooler DC/Baltimore suburbs may see an outside chance as well. Meanwhile, a Freeze Watch has been issued for Highland and Pendleton counties with lows expected to be near 30 degrees. This presently runs from 10 PM Saturday until 9 AM Sunday. Cyclonic flow aloft continues to finish out the weekend. The cold advection regime does relax which will allow temperatures to slightly bump up from Saturday's readings. The current forecast calls for low/mid 60s with mid 40s to mid 50s across the mountains. High pressure will maintain lots of sunshine with dry conditions ahead. Forecast lows are a few degrees milder than the prior night. Patchy frost will again be possible for the Blue Ridge westward. && .LONG TERM /MONDAY THROUGH THURSDAY/... High pressure will continue to build over the Mid-Atlantic Sunday into Monday as an upper-level trough lifts away across the Canadian Maritimes. Below normal temperatures are expected Sunday, moderating some by Monday. A backdoor front may approach by Tuesday, but no precipitation is expected with it since forcing and moisture appear to be lacking. Its biggest impact will be a slight pause in moderating temperatures. A stronger trough/front will likely approach during the second half of next week, though timing/strength/amplitude uncertainties increase during this time. This system will probably bring the next chance for appreciable precipitation, but with questions remaining around exactly when and how much. && .AVIATION /14Z FRIDAY THROUGH TUESDAY/... VFR conditions expected at all terminals through the weekend. A cold front will move through the area this afternoon and evening leading to a shift to west to northwesterly winds. These may become locally gusty up to around 25 knots by the mid- evening and into portions of the night. VCSH for the Baltimore terminals, but without any expected restrictions. These breezy winds persist through the first half of Saturday before dropping off as a high pressure approaches from the west. Tranquil conditions are expected on Sunday with the ridge in place. VFR conditions are expected Monday and Tuesday with W/NW winds becoming S generally 10 knots or less. && .MARINE... A cold front approaching from the Ohio Valley will lead to changes across the area waterways. A surge of northwesterly winds reach the northern Chesapeake Bay by the late afternoon to early evening. This eventually overspreads the tidal Potomac and remainder of the Chesapeake Bay. Consequently, Small Craft Advisories remain in effect from the late afternoon and into early Saturday morning. Such conditions likely will continue into portions of the morning and afternoon as well. Winds gradually begin to relax Saturday evening and into Sunday. High pressure is expected to be moving offshore early next week. This should result in generally light W/NW flow becoming S. && .TIDES/COASTAL FLOODING... A Coastal Flood Advisory remains in effect for Anne Arundel County around Annapolis. There has been a slight upward trend in the anomalies upstream, and these area most likely to creep northward given the light flow. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...Freeze Watch from Saturday evening through Sunday morning for VAZ503-504. WV...Freeze Watch from Saturday evening through Sunday morning for WVZ505-506. MARINE...Small Craft Advisory from 2 PM this afternoon to 6 AM EDT Saturday for ANZ530. Small Craft Advisory from 2 PM this afternoon to 1 PM EDT Saturday for ANZ531-538-539. Small Craft Advisory from 6 PM this evening to 1 PM EDT Saturday for ANZ532-533-536-537-540>542. Small Craft Advisory from 6 PM this evening to 4 PM EDT Saturday for ANZ534-543. Small Craft Advisory from 6 PM this evening to 6 AM EDT Saturday for ANZ535. && $$ SYNOPSIS...DHOF NEAR TERM...BRO/KLW SHORT TERM...BRO LONG TERM...DHOF AVIATION...KLW/DHOF MARINE...KLW/DHOF TIDES/COASTAL FLOODING...KLW