Area Forecast Discussion
Issued by NWS Wakefield, VA

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000 FXUS61 KAKQ 282237 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 537 PM EST Mon Nov 28 2016 .SYNOPSIS... High pressure becomes shifts off the coast tonight resulting in an increasing southerly flow Tuesday and Wednesday. A complex weather system approaches the region from the west for midweek...bringing an increased chance of rain to the region. A cold front will push through the area early Thursday. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... Surface high pressure has shifted off the coast resulting in a gradually increasing southerly flow. High level cirrus streaming across the area ahead of the next system has a few thinning areas, but the thinning occurred a little too late to realize peak heating for the day keeping highs in the low to mid 50s. Mid level clouds will start to spread in from the SW early this evening rapidly overspreading much of the forecast area overnight as the low level jet increases. models suggest a low level jet of 40 to 50 kt setting up between 06z and 12z. This along with a weak upper wave will bring some light rain and drizzle to portions of the forecast area late tonight, but qpf overnight will be low. Temperatures will fall into the upper 40s (some mid 40s well inland possible) this evening, but then warm overnight as the low level jet sets up and surface southerly flow increases. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... The primary upper trough will continue to sharpen and dig south over the Plains Tue and Wed. Models are in continued agreement suggesting showers tuesday morning into the afternoon mainly along and north of I-64 (including MD) as the first weak upper wave moves through. Even in areas (across southeast VA and northeast NC) where there is less shower activity skies will remain mostly cloudy. There will be a break/lull in the overall shower activity Tue night and Wed morning before the main push with the upper trough and attending cold front come through late Wed. POPS increase once again Wed afternoon as forcing increases ahead of the front with likely to categorical POPS expected across the entire region Wed afternoon into Wed night as the system pushes from west to east. Given the warm/moist airmass in place and forcing there is a risk for a few thunderstorms and SPC has the area in a Marginal Risk for severe storms. Total (average) QPF Tue-Wed 0.50-0.75" NW to 0.20-0.35" SE.Everything pushes off the coast Thursday morning as much cooler air rushes in behind the front. Strong pre-frontal WAA will make for a couple of very mild to warm days Tue and Wed. Highs Tue in the upper 60s well inland to lower 70s SE VA- NE NC. Highs Wed in the near 70 well inland mid 70s in SE VA- NE NC. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... The extended period is expected to begin with cool high pressure gradually building across the Southeast Conus. This will result in dry conditions, with temperatures slightly below seasonal averages, but within -1 st dev. Sky cover is expected to be mostly clear, however, increasing high clouds are possible Saturday. Forecast lows Friday morning range from the mid 30s to around 40, followed by highs Friday in the low/mid 50s. Slightly cooler Friday night and Saturday with lows ranging from the low 30s inland to the mid/upper 30s along the coast, and highs around 50. There is the potential for highs to remain in the 40s Saturday if thicker high clouds arrive earlier. GFS/ECMWF diverge Saturday night through Sunday night, with the GFS depicting a progressive nrn stream wave tracking across the region, while the ECMWF shows a phased system lifting ne through the Ohio Valley. At this time forecast PoPs are ~30%, which is slightly above climo. Model differences continue into Monday, but the consensus is for a drier pattern. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... VFR to start off the 18Z taf period with sfc hi pressure sliding offshore and high clouds streaming in from the west. A low pressure systm also approaches from the west tonight, and southerly winds increase tonight into Tue as cigs drop as well. Included shras in the last six hours of the TAF period at KRIC/KSBY where confidence is the highest, but rain is psbl at all the TAF sites Tue as are MVFR cigs. Periodic sub-VFR conditions are expected through midweek with another (better) chance of rain Wed/Wed night. && .MARINE... High pressure slides offshore tonight ahead of a trough pushing through the Ohio Valley. Southerly flow is expected to increase later tonight into Tuesday with wind speeds reaching 15- 25kt, with gusts up to 30 kt over the ocean. Waves in the Bay build to 3-4ft, with 5-7ft (highest n) in the ocean. The trough lifts newd through New England Tuesday night with the wind becoming sw and diminishing to 10-15kt. Waves in the Bay subside to 2-3ft. However, seas likely remain 4-6ft. SCAs for the Bay/ocean/sound remain as is, and an SCA flag has been raised for the rivers from 12z-21z. A cold front is expected to push through the Ohio Valley Wednesday and then push off the Mid-Atlantic Coast late Wednesday night. The wind should shift bay to south Wednesday into Wednesday evening and increase to 15-25kt. It is likely that another round of SCAs will be necessary for the Bay/Sound/rivers, while seas may not drop below 5ft (especially n) between the two events. The wind becomes westerly at 10-15kt (minimal CAA) behind the front late Wednesday night into Thursday as the front shifts offshore. A nw wind of 10-15kt should prevail Friday into Saturday as high pressure builds across the Southeast Conus. Seas subside from 3-4ft to 2-3ft, with ~2ft waves in the Bay. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory from 7 AM to 4 PM EST Tuesday for ANZ635>638. Small Craft Advisory from 4 AM to 7 PM EST Tuesday for ANZ630>634. Small Craft Advisory from 7 AM Tuesday to 6 AM EST Wednesday for ANZ650-652-654-656-658. && $$ SYNOPSIS...ALB/JAO NEAR TERM...ALB/JAO SHORT TERM...ALB/JAO LONG TERM...AJZ AVIATION...MAS MARINE...AJZ/JDM is the U.S. government's official web portal to all federal, state and local government web resources and services.