Area Forecast Discussion
Issued by NWS Wakefield, VA

Home | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KAKQ 202359 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 759 PM EDT Thu Oct 20 2016 .SYNOPSIS... A cold front approaches from the west tonight and crosses the region on Friday...followed by breezy and much cooler, more seasonable conditions Friday night through the weekend. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... Latest sfc analysis shows a frontal boundary over the OH Valley, low pressure well east of FL, and high pressure centered over SE Canada. The cold front approaches from the west tonight, with dry conditions expected ahead of the front and some increasing clouds late. Otherwise, included some patchy fog with calm/light winds. Low temps in the lwr 60s. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY/... After several recent dry days, shwrs are likely across the area Fri as a cold frnt and associated mid-level shortwave trough cross the Mid Atlc. The frnt has slowed down a bit with the latest guidance, so expect the rain to not start along the I-95 corridor until early-mid aftn, and closer to the coast late aftn-early eveng. PoPs are 60-70% most areas. Kept thunder out of the forecast as well, with most areas expected to only receive a tenth to a quarter inch of qpf. Temps Fri lwr than previous days...highs mainly in the 70s...highest over eastern areas. Chances of rain decrease fm west to east Fri evening as the frnt pushes offshore and drier air moves in from the west. Low temps Fri night mainly 45-50F. Dry wx with decreasing clouds for Sat with much cooler conditions under strong caa...high temps only in the low-mid 60s. Winds will be highest along the coast Fri night/Sat where sustained winds will average 20-25 mph with gusts of 30-35 mph. Farther inland, gusts will average 20-25 mph. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... High pressure settles across the sern states Sat night and Sun as intense low pressure moves into eastern Canada. Dry with slowly diminishing winds Sat nite. Lows in the low to mid 40s except upr 40s to lwr 50s sern coastal areas. Highs Sun in the mid 60s. Lows in the upr 40s to lwr 50s. Next cold front crosses the region Monday. No significant moisture noted so expect a dry fropa. CAA lags so expect a milder day with highs in the upr 60s to lwr 70s. Lows in the 40s except lwr 50s sern coastal areas. Canadian high pressure builds across the area for the mid week period. Remaining cool and dry. Highs Tue 60-65. Lows in the 40s to lwr 50s sern coastal areas. Highs Wed in the 60s. Lows in the mid 40s to lwr 50s. Low pressure progged to move from the nations mid section Wed to the Gt Lakes region Thurs. Limited moisture returns in advance of the approaching warm front. Added slght chc pops Thu across the northern half of fa with this feature. Highs 65-70. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
As of 23Z...High pressure remains centered over Atlantic Canada with weak low pressure lingering to our west over portions of the Cumberland Plateau. Low pressure is still expected to gradually lift to the northeast tonight as a strong upper level trough digs across the Midwest. Weak high pressure will linger near Mid- Atlantic coast tonight before a cold front approaches the area Friday afternoon. Tricky forecast tonight with the potential for fog development. Weak high pressure near the coast and modest low-level moisture will bring the potential for IFR/stratus at all TAF sites tonight. Guidance continues to show the most favorable fog development near the coastal sites with less confidence further inland. As with the previous couple of mornings, conditions should begin to improve after 14Z. A trough and associated cold front will approach the area during the afternoon. Am expecting some shower activity to work into RIC after 18Z and continue to move west to east across the area. Winds will flip towards the west/northwest and begin to increase Friday afternoon. Outlook: High pressure will build back into the region late in theday on Saturday and into Sunday. Another cold front (dry frontal passage) will sweep across the area Monday before high pressure makes a return on Tuesday.
-- End Changed Discussion --
&& .MARINE... Return S-SW flow around high pressure off the sern coast results winds below 15 kts through mid day Fri. Latest guidance has slowed the cold frontal passage down by about 2-3 hours Fri aftrn. Thus, made a few tweeks in the SCA headlines for the rivers. Pushed back the starting time until 22Z which comes up Fri eve rather than Fri aftrn. Went ahead and extended the SCA headlines for the rivers and Currituck sound through Sat aftrn (end of 4th period). Most if not all guidance points to a strong CAA surge late Fri night into Sat morning across the Ches Bay and coastal waters. Given rather sharp pressure rises behind the front, 925-950 MB winds between 35-40 kt, falling H85 temps and water temps arnd 70F, confidence is high that enough mixing occurs to upgrade the gale watch to a warning with this package. Even the old "Boston Technique" suggests the strongest gusts (up to 40 KTS) across the northern waters with gusts to 35 KT across the south. Gusts to 35 KT possible for a few hours late Fri nite across the NC coastal waters so went ahead and added them to the gale warning. The offshore NW flow will keep seas from building to anything higher than 5-7 ft most areas (highest out 20 NM offshore). Bay waves build to 4-5 ft. Winds remain elevated Sat night and Sunday but should diminish to some extent. The next front crosses the area Mon. Appears another surge (albeit much weaker) will likely require minimal SCA headlines late Monday or Monday night. && .CLIMATE... Record high temperatures for today are listed below: RIC 89 (1984) ORF 87 (1984) SBY 84 (1984) && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory from 6 PM Friday to 4 PM EDT Saturday for ANZ633-635>638. Gale Warning from 8 PM Friday to noon EDT Saturday for ANZ630>632-634-650-652-654-656-658. && $$ SYNOPSIS...MAS NEAR TERM...MAS SHORT TERM...MAS LONG TERM...MPR AVIATION...AJB MARINE...MPR CLIMATE... is the U.S. government's official web portal to all federal, state and local government web resources and services.