Area Forecast Discussion
Issued by NWS Wakefield, VA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KAKQ 112052 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 352 PM EST Mon Dec 11 2017 .SYNOPSIS... A low pressure system will move east from the Great Lakes region tonight into the Northeast states Tuesday. This low will drag a strong cold front through the Mid Atlantic by late Tuesday. Expect markedly colder temperatures across the region then for Tuesday night and Wednesday. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... Latest sfc analysis shows ~1024 mb high pressure centered over the GOM with ~1004 mb low pressure over the Midwest. Aloft, a potent mid-level shortwave trough is diving down towards the base of the longwave trough. Dry weather expected tonight with just some increasing clouds late ahead of the approaching system. With light southerly flow and some cloud cover, temps will be a bit higher than those of last night...lows ranging through the 30s. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... Short term period will feature below normal temps on avg with a couple small chances for pcpn. For Tue...aforementioned strong cold front will cross the area late in the day. WNW winds will gust up to 20-30 mph. Despite decent forcing, moisture will be lacking and thus have limited any chance for pcpn (plain rain) in the aftn to the Lwr Eastern Shore where 20-30% PoPs are carried. Any amounts will be very light. High temps in the upr 40s to mid 50s. Dry and cold then for Tue night with lows in the upr teens to low 20s most areas. This combined with continued gusty winds will lead to wind chill values in the upr single digits to teens...lowest over northern areas. Dry into Wed as well as weak sfc high pres slides south of the area. Expect wind chill values in the 20s even during the middle of the day with winds gusting up to 20-30 mph and high temps only in the mid 30s most spots...15-20 degrees below normal. Next chance of pcpn arrives Wed night with an approaching clipper system. Have introduced a 20% of snow showers everywhere...and may have to do potentially increase PoPs in future updates. Any snow should end by Thu morning, with a dry day then for Thu. Temps moderate then into Thu with highs in the 40s under a partly cloudy sky. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... Clipper system approaches from the WNW Thu night...then crosses the local area Fri as weak sfc lo pres passes just S and E. 12Z/11 GFS and ECMWF both suggest there is a potential for wintry pcpn on Fri (esp N and NW sections)...maintaining cold air across the region. During the weekend...upper level flow relaxes allowing for moderation into next week. Lows Thu night from the m20s NW to the m30s at the coast in SE VA-NE NC. Highs Fri from the m30s NW to around 50F in far SE VA-NE NC. Lows Fri night from the m-u20s inland to 30-35F at the immediate coast. Highs Sat in the l-m40s. Lows Sat night in the l-m30s. Highs Sun in the l-m50s. Lows Sun night in the 30s to l40s. Highs Mon in the l-m50s. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... VFR conditions expected through the 18z TAF period and beyond. SKC for today with light S/SW winds. Some increasing clouds tonight into Tue ahead of a mid-level shortwave trough and associated strong sfc cold front. Mainly just some SCT-BKN mid clouds with this. SW winds shift to W then NW as the front slides through the area Tue, with gusts up to 20-30 kt at times Tue aftn. Expect VFR conditions to prevail for much of the week ahead. && .MARINE... A complex marine forecast expected over the next 2-3 days as a strong and prolonged CAA surge progged behind an arctic cold front Tues night into Wed. Ahead of all this is a "lull" in sfc winds this evening as high pressure slides across the region. The return SSW flow progged to quickly increase later tonight as the pressure gradient tightens ahead of the approaching cold front. The different SCA criteria for the Bay vs the ocean results in different starting times across the marine area. Thus, will start SCA headlines for the Ches Bay later tonight and continue thru 00Z Wed as the gradient tightens. Winds across the Currituck sound and local rivers don`t get to SCA levels until Tue. Cold frontal passage by 00Z Wed. Strong CAA surge noted on all models with most of the guidance showing gusts in the 35-40 kt range across the coastal waters / mouth of the bay with 35 kt over the rest of the Ches Bay. Thus, think confidence high enough to go with a gale warning for these areas starting at 00Z Wed and continuing through 21Z Wed. Left strong SCA`s for the rivers and sound for now. A weaker system progged to cross the region later in the week. Winds/seas subside by Thursday under SCA levels. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory from 10 AM Tuesday to 4 PM EST Wednesday for ANZ633-635>638. Small Craft Advisory from 1 AM to 7 PM EST Tuesday for ANZ630>632-634. Gale Warning from 7 PM Tuesday to 4 PM EST Wednesday for ANZ630>632-634-650-652-654-656-658. && $$ SYNOPSIS...MAS NEAR TERM...MAS SHORT TERM...MAS LONG TERM...ALB AVIATION...MAS MARINE...MPR is the U.S. government's official web portal to all federal, state and local government web resources and services.