Area Forecast Discussion
Issued by NWS Sterling, 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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
535 FXUS61 KLWX 290900 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 400 AM EST Tue Nov 29 2016 .SYNOPSIS...
-- Changed Discussion --
A warm front will lift through the area today. An area of low pressure will move across the area Wednesday with a cold frontal passage Wednesday night. High pressure will return to the region Friday and Saturday. Low pressure will approach the region Sunday.
-- End Changed Discussion --
&& .NEAR TERM /TODAY/...
-- Changed Discussion --
As of 3am, vertically stacked cold core low with a 981mb surface low is over junction of ND, SD, and MN. A shortwave trough axis is apparent in water vapor imagery over MI. An associated cold front is over the TN valley and extends SW to Houston. A swath of rain continues to move NE from AL, though most of the moisture is being squeezed out over the SErn states. One brief round of rain has moved across the LWX CWA with the second round being much more substantial and taking through most of today to cross the area. QPF generally a quarter to half an inch through tonight. Gusty winds up to 40 mph possible with showers particularly over SErn portions of the CWA where convective activity is most robust. Maxima upper 50s north and mid 60s south. 60F dewpoints lift into southern portions of the area, a rarity for late November. Fog is expected to develop tonight especially east of the Blue Ridge where rain clears near or after sunset. Minima generally less than 10 degrees below the maxima with continued south winds.
-- End Changed Discussion --
&& .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
-- Changed Discussion --
A digging long wave trough/jet stream over the intermountain west will keep the low centered over MN through tonight and keep the SErn CONUS cold front essentially in place. It will take until Wednesday night for the longwave trough axis to move across the OH valley for the cold front to push through the Mid-Atlantic. Rain associated with the second round/long wave trough breaks out late tonight as convergence spreads in from the OH valley. Weak instability may allow isolated thunderstorms east of I-95 Wednesday afternoon. Gusty west wind up to 30 mph Thursday behind the cold front with little upslope snow. Maxima mid to upper 50s in dry air advection.
-- End Changed Discussion --
&& .LONG TERM /FRIDAY THROUGH MONDAY/...
-- Changed Discussion --
High pressure over the area Friday and Saturday. Highs both days in the lower 50s east of the mountains...mid to upper 40s west except colder in the Highlands. Lows both night close to freezing. Sunday...models are diverging on the timing of the short wave that could bring the region some more rain. Euro is the faster of the two..bringing extensive moisture into the Mid Atlantic Sunday afternoon ahead of a warm front draped over the Gulf states. Rain showers would be the predominant p-type...although this could mix with snow at elevation above 2000 feet. Short wave to approach and move through the region Monday. It is again possible that rain could mix with snow Sunday night as temperatures drop close to freezing. This would revert to all rain Monday..with precipitation chances likely ending by the end of the day as the trough moves offshore.
-- End Changed Discussion --
&& .AVIATION /TODAY THROUGH SATURDAY/...
-- Changed Discussion --
MVFR conds generally today as rain overspreads the DC metros with increasing south winds. IFR cigs possible by this evening. Fog likely overnight between two rain events, the second beginning late tonight. Showers with isolated thunder east of I-95 Wednesday. Cold front crosses Wednesday night with 25 kt peak west gusts Thursday. VFR conditions expected Friday and Saturday.
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
South winds increase today as rain overspreads the area. Gusty showers and strong winds mainly this afternoon warrant gale warning for central and southern MD waters today. SCA conditions at least through Thursday with a cold front crossing Wednesday night. Strong south winds ahead may mix down Wednesday and warrant another Gale. SCA may be needed for portions of the waters Friday as high pressure builds into the waters. No problems expected Saturday.
-- End Changed Discussion --
&& .TIDES/COASTAL FLOODING...
-- Changed Discussion --
Water levels will continue to rise on southerly flow. Minor coastal flooding will be possible at Annapolis at times of high tide (5:28 pm).
-- End Changed Discussion --
&& .LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...None. MD...Wind Advisory until 1 PM EST this afternoon for MDZ501. VA...Wind Advisory until 1 PM EST this afternoon for VAZ025>027-029- 503-504-507-508. WV...Wind Advisory until 1 PM EST this afternoon for WVZ055-501>503- 505-506. MARINE...Small Craft Advisory until 6 AM EST early this morning for ANZ532>534-537-540>543. Small Craft Advisory from 6 PM this evening to 6 AM EST Wednesday for ANZ532>534-537-540>543. Gale Warning from 6 AM this morning to 6 PM EST this evening for ANZ532>534-537-540>543. Small Craft Advisory until 6 AM EST Wednesday for ANZ531-536- 538-539. Small Craft Advisory until 6 PM EST this evening for ANZ530- 535.
-- End Changed Discussion --
&& $$ PRODUCTS...BAJ/WOODY!

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