Area Forecast Discussion
Issued by NWS Wakefield, VA

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000 FXUS61 KAKQ 290836 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 336 AM EST Tue Nov 29 2016 .SYNOPSIS... 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 PM THIS EVENING/... Deep upper level trough is located over the Plains states attm...w/ strong SW flow across the ern CONUS. Initial area of shras approaching from the W...though there has been a decreasing trend. Initial impulse will be crossing the local area through today. Dynamics rather weak as S low level flow continues to bring increasing moisture. Will have the highest PoPs (50-80%) across the NW 1/2 of the FA through this afternoon/early evening...tapering to 15-30% in far SE VA-NE NC. S winds will be gusty through the 20-30 kt. Temperatures have risen overnight...into the 50s for most areas. Highs today from the m60s NW to the l70s SE. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/... Mid-upper level moisture largely departs early tonight...leaving lo levels moist. Winds to lower...and potential exists for lo cigs/vsbys developing...esp inland. Otherwise...PoPs to be 20-30% w/ lows in the u50s-l60s. A second s/w will be tracking NE in SW flow aloft...initially invof TN/OH Valleys by late tonight...then to the local area by Wed afternoon. Modest instability at best ahead of that system by Wed afternoon...mainly E of I 95. Developing area of shras expected over the higher terrain to the W Wed morning...which spreads to the E by late Wed. Potential for moderate/heavy RA and isold T the farther E the systems gets. Highest PoPs W and central locations Wed...then shifts E by late Wed evening. Otherwise...mostly cloudy inland (highs Wed in the u60s-around 70F)...VRB clouds at the coast (highs Wed in the l-m70s). After shras/possible isold T in the evening (highest PoPs E of I 95)...clearing out W-E after midnight Wed night. Lows in the u40s W to u50s at the coast. Cooler/dry wx expected Thu w/ WNW winds. Sunny to partly cloudy w/ highs in the m-u50s...except l60s in far 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 /08Z TUESDAY THROUGH SATURDAY/... Starting w/ VFR conditions as cigs lowering to 3-6kft across the FA the next few hours. Area of shras approaching from the W as sfc winds increase. Low level jet in place w/ strongest winds generally from 1-2kft...have continued LLWS for RIC until 11-13Z/29. Expect cigs to fall to MVFR by daybreak into central VA...but still not anticipating IFR conditions at the TAF sites due to mixing. Light shras become likely KRIC and KSBY early Tuesday morning. Light shras to persist through Tue morning...w/ the best probs RIC nwd. Lower confidence to the SE. MVFR ceilings anticipated to persist, with MVFR visibilities at times. Showers taper NW to SE during the late afternoon/evening. Breezy...w/ S gusts of 20 knots inland and 25 to 30 knots near the coast. Lo prob for LIFR/IFR conditions by late tonight as winds subside and mid-upper level moisture clears out. Periodic sub-VFR conditions are expected into Wed night with another (better) chance of RA by Wed afternoon/evening. Clearing out/VFR conditions return Thu-Fri. && .MARINE...
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A trough pushing through the Ohio Valley will cause an increase in wind speeds across the marine area today, reaching 15-25kt with gusts up to 30 kt over the ocean. Waves in the Bay build to 3-4ft, with 5-7ft seas in the ocean (highest n). The trough lifts newd through New England tonight with the wind becoming sw to w and diminishing to 10-15kt. Waves in the Bay subside to 2-3ft. However, seas remain 4-6ft. SCAs for the Bay/Rivers/Sound come down by 7 pm. 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 to the 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. Therefore, have extended SCAs for the ocean into Wed night. 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.
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&& .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 4 PM EST this afternoon for ANZ635>638. Small Craft Advisory until 7 PM EST this evening for ANZ630>634. Small Craft Advisory until 6 AM EST Thursday for ANZ650-652- 654-656-658. && $$ SYNOPSIS...ALB/JAO NEAR TERM...ALB SHORT TERM...ALB/JAO LONG TERM...AJZ AVIATION...ALB/SAM MARINE...JDM is the U.S. government's official web portal to all federal, state and local government web resources and services.