Area Forecast Discussion
Issued by NWS Wakefield, VA

Current Version | Previous Version | Graphics & Text | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KAKQ 031955 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 255 PM EST Sat Dec 3 2016 .SYNOPSIS...
-- Changed Discussion --
High pressure builds across the region tonight and Sunday. Low pressure passes south of the region Sunday night into Monday. A complex area of low pressure crosses the region Tuesday. A strong cold front crosses the area Thursday.
-- End Changed Discussion --
&& .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --
Sfc high slides east ivof Mason - Dixon line tonight. Tsctns show high level moisture overspreading the region ahead of the developing low to the south. Thus, expect mstly clr/partly cloudy skies this evening becoming mstly cloudy across the west late. Temps quickly drop after sunset then level off. Lows in the low-mid 30s except upr 30s along the sern beaches.
-- End Changed Discussion --
&& .SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
-- Changed Discussion --
High pressure slides east at a position along the Delmarva Sunday aftrn. While this high keeps it dry in the lower levels, the mid/upr levels quickly moisten throughout the day. So while there could be some dim sunshine early Sun morning across the east, expect the day to turn out cloudy to mostly cloudy with any pcpn remaining sw of the fa thru 00Z Mon. The clouds hold temps down with highs in the upr 40s-lwr 50s. First wave of energy from the low over the deep south ejects ENE along a developing trof over the Carolinas Sunday night. Models agree in quickly spreading moisture NE across the fa Sun evening. Best lift/support progged over the SERN half of the fa where greatest QPF will be (1/4 to 1/3rd inch). Will carry chc/likely pops during the evening then ramp up to likely pops most areas except categorical pops across SERN zones after midnight. In-situ wedge leads to a chilly rain with lows in the upr 30s-lwr 40s. The sfc low pushes off the coast near HAT Monday morning with weak ridging building south across the area throughout the day. Despite the high pressure building in, TSCTNS show enough leftover moisture at various levels to keep cloudy to mostly cloudy skies. Chc pops in the morning (except likely across extreme SE zones) lower to slght chc across NC zones in the afternoon. Highs in the low-mid 50s. Timing differences arise wrt the pcpn arrival Monday night with the NAM the fastest, GFS the slowest with the 12Z ECMWF a compromise between the two. Will lean toward the faster solution given pcpn usually breaks out a bit faster given an overrunning scenario. Will carry low chc pops Monday eve ramping up to chc to likely pops after midnight. Lows in the mid 30s NW to upr 40s SE. Tuesdays forecast is another typical Mid Atlantic system where low pressure tracks NE along the mts with a secondary low tracking NE along the coast. Copious amounts of both GOM/Atlantic moisture will fall into a strong wedge across the piedmont. Expect a wide temp range across the fa along with a much needed/widespread rainfall. Challenge will be to define where the coastal low tracks as the NAM has an inland track with both the GFS/ECMWF tracking the low right along the coast. For now, will keep all pcpn stratiformed with categorical pops. QPF averaging bwtn 1/2 to 3/4 inches. Temps tricky but will continue with a sharp thermal gradient. Highs from mid-upr 40s across the wedged piedmont to near 60 across sern coastal zones.
-- End Changed Discussion --
&& .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... Lingering trofiness keeps residual moisture across the area Wed with low chc pops east of I95 Wed. Seasonable with highs 55-60. Lows mid 30s to mid 40s. An anomalous upper level trough digs across the central US Thursday and into the eastern US Friday. A quick moving cold front progged to push across the region Thursday, ushering in the coldest air mass of the season. Numerical and statistical guidance still indicating a large spread of temperatures Thursday ahead of the front (depending on the frontal timing), so have opted to follow the lowering mean into the low to mid 50`s Thursday. Limited moisture return and westerly flow will limit precipitation chances Thursday and Thursday night, but will keep mention of slight chance POPs for the northwest Piedmont to the Maryland Eastern Shore. As impressive dynamics/height falls reach the local area Thursday night, might not be able to rule out some flurries across the northeast as strong cold air advection combines with lingering mid level moisture. Lows drop into the mid/upper 20`s inland to low 30`s near the coast. A cool/breezy/sunny/dry day forecast Friday as the latest GEFS indicates 850mb temperatures around -10 to -12C (-2 standard deviations). Highs are expected to warm only into the low 40`s (upper 30`s possible Piedmont). Add in a breezy northwest wind and wind chills may only warm into the 30`s. Dewpoints in the teens will allow temperatures to drop into the 20`s (teens possible inland if trends continue) Friday night under a clear sky. 850Mb temperatures progged to warm to around -6 to -8 based on the latest ensemble guidance (still -1 standard deviation). Surface high pressure builds across the Southeast, resulting in less mixing and temperatures only warming to around 40. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... VFR conditions prevail across the region with generally NW-N winds less than 10 kt. Some gustiness to 20 kt is occurring across the Eastern Shore region. High pressure builds in from the west through the weekend leading to continued dry weather. Scattered mid to high clouds are possible across northern sections from RIC to SBY this evening, with any cloud bases generally to remain above 6000 feet. Outlook: Clouds will begin to increase late tonight and into Sunday. The next chance for showers arrives Sunday night, with rain likely into Tuesday with periodic visibility restrictions and MVFR conditions Tuesday afternoon and night. && .MARINE... Latest surface analysis centers ~990mb low pressure off the Canadian Maritime with ~1029mb high pressure over the Midwest. The result is a northwest wind of 15 to 25 knots over the local waters early this morning. Waves generally 2-4 feet and seas 3-5 feet. The pressure gradient relaxes over the lower Bay and southern coastal waters late morning/early afternoon as high pressure builds southeastward over the Carolinas. Northwest winds diminish to 10-20 knots in the southern waters this afternoon, but remain 15 to 25 knots in the northern waters. Have maintained SCA headlines for the southern waters through 1pm (seas subside to 3-4 feet), and have extended the northern waters through this evening. Seas in the northern waters 4- 5 feet. Sub-SCA conditions return to the waters late tonight as high pressure centers over the Mid-Atlantic region. High pressure centers over the waters Sunday with winds diminishing to at or below 10 knots. Waves 1-2 feet and seas 2 feet. High pressure slides offshore Sunday night and Monday, but a ridge remains over the waters as a coastal front aligns along the Southeast coast. Flow becomes southerly Sunday night, and then northwesterly late Monday and Monday night as high pressure builds over the Ohio Valley. Speeds remain at or below 15 knots. High pressure builds over the Northeast Tuesday as low pressure slowly lifts along the stalled Southeast coastal trough. Flow becomes onshore at 10-20 knots, with seas building to0 4-6 feet late Tuesday and Tuesday night. Waves build to 2-4 feet in the lower Bay. Low pressure lifts off the Mid-Atlantic coast Wednesday with northwest flow Wednesday night. A strong cold front Thursday will usher in the coldest and driest air mass of the season Thursday night through Friday night. Strong SCA (or even Gale) conditions are possible. && .AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 1 AM EST Sunday for ANZ630-631-650- 652.
-- End Changed Discussion --
&& $$ SYNOPSIS...MPR NEAR TERM...MPR SHORT TERM...MPR LONG TERM...MAS AVIATION...JEF MARINE...MAS

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.