Area Forecast Discussion
Issued by NWS Wakefield, VA

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163 FXUS61 KAKQ 290157 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 957 PM EDT Wed Jun 28 2017 .SYNOPSIS...
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High pressure will reside off the Mid Atlantic Coast tonight through Friday. A trough of low pressure will set up over the area for late Friday night through Saturday.
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Update...High clouds have cleared the area as high pressure resides just off the Mid Atlantic Coast this evening. Temperatures are cooling off nicely as a result and still anticipate lows in the upper 50s NW to mid 60s SE. High clouds will return overnight as westerly flow aloft allows for re-generation of leeside cirrus. Additional (albeit weak) support from shortwave energy/moisture passing across nrn VA should focus the cirrus across the nrn half of the forecast area.
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&& .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... The high will continue to slide out to sea later Thu thru Fri. Dry wx will prevail thru at least the first part of Fri for the entire region. SSW flow will start to increase on Thu resulting in a warmer and slightly more humid airmass. Mostly sunny with highs in the mid to upper 80s. Mostly clear Thu night with lows in the mid to upper 60s. That SSW flow will bring increasing dewpts/low level moisture into the region for Fri thru Sat. An isolated shower or tstm could affect srn third of the area Fri aftn into Fri night. Then, isolated to sctd showers or tstms will be possible Sat aftn into Sat evening, as a trough of low pressure sets up over the region. Highs on Fri will range fm the mid 80s to lower 90s. Lows Fri night mainly in the lower 70s. Highs on Sat in the upper 80s to lower 90s. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... Long term period will feature a fairly typical summertime pattern with a cold front weakening near or just N of the area Sat night/Sun morning. Still capping PoPs at 20-40% Sat night (highest N) as more significant forcing stays NW closer to the decaying front. Sunday will see the front wash out across the local area, will maintain 20% PoPs N/NW and 30% PoPs most other areas (up to 40% over northeast NC). Highs in the upper 80s to lower 90s. Mon/Tue will see the local area generally in light flow and minimal forcing. It will be very warm and humid with enough aftn/early evening instability for ~20% PoPs most areas (and with a little more instability will keep PoPs to near 30% for interior NE NC) Highs 90-95 F inland and mid- upper 80s/lower 90s near the coast. Lows generally 70-75 F. GFS/ECMWF diverge with respect to details late Tue/Wed, the ECMWF suggesting building heat and lower PoPs while the GFS supports slightly cooler wx and a higher chance for daily tstms. Have genly split the difference and just carried 20 to 30% PoPs during climo favored timeframe (late aftn and evening). Highs continue to be 90-95 F inland and upper 80s/around 90 F along the coast. && .AVIATION /02Z THURSDAY THROUGH MONDAY/... High pressure moves off the coast overnight allowing for more of a southerly flow on Thursday. A cold front over the Midwest will approach this weekend and then stall to the north of the area. High confidence that VFR conditions will continue through the 00Z TAF period. Mainly clear skies and variable winds are anticipated overnight. Scattered cumulus, around 6000 feet, develops mainly after 16Z. Winds increase out of the south by tomorrow afternoon, occasionally gusting to near 20 knots. Outlook: Afternoon/evening showers and thunderstorms will be possible Saturday through Monday. && .MARINE... Sfc high pressure now centered along the SE VA coast, with a light onshore flow of 5-10 kt over the waters. Seas avg 2-3 ft for NC coastal waters and 1-2 ft or less elsewhere. The high slides just offshore tonight, allowing a brief surge of SSE flow up the Bay. Not enough gradient with this for any headlines, but waves may build to 2-3 ft across the northern Bay by 06Z tonight with ~15 kt winds. A somewhat more significant southerly flow will result;t from a tighter pressure gradient by late Thu aftn and especially Thu night. Have raised SCA headlines for the Bay zones N of New Pt Comfort for S winds around 20 kt with some gusts to around 25 kt (strongest winds most likely from 00-06Z/Fri). Farther south in the Bay and across the rivers, the gradient is a little weaker and confidence therefore lower and have held off for now regarding headlines as this is a late 2nd/3rd period event. In these areas, expect sustained winds to avg 15 kt with gusts to around 20 kt. Other area where a marginal SCA event will be possible is the coastal waters N of Parramore Island with a SSW wind to around 20 kt. Wavewatch/NWPS blend suggests mainly 4 ft seas in these areas with the potential for seas approaching 5 ft out 20 NM offshore. Seas farther south should stay at or below 3-4 ft. Similar conditions Fri aftn/evening, though guidance supports winds being slightly weaker compared to Thu night. A slow moving cold front approaches from the NW Sat but weakens by the time it reaches the local area on Sunday. Outside of any tstms, conditions will be sub-SCA with winds 10-15 kt or less and seas mainly 2-3 ft and waves 1-2 ft. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory from 4 PM Thursday to 4 AM EDT Friday for ANZ630-631. && $$ SYNOPSIS...BMD/TMG NEAR TERM...BMD SHORT TERM...TMG LONG TERM...LKB AVIATION...AJB/LSA MARINE...LKB is the U.S. government's official web portal to all federal, state and local government web resources and services.