Area Forecast Discussion
Issued by NWS Sterling, VA

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
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 KLWX 110838 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 338 AM EST THU FEB 11 2016 .SYNOPSIS... HIGH PRESSURE BUILDS IN ACROSS THE REGION THROUGH FRIDAY. A STRONG COLD FRONT WILL CROSS THE REGION FRIDAY NIGHT WITH ARCTIC HIGH PRESSURE BUILDING IN THE WAKE FOR THE WEEKEND. LOW PRESSURE MAY IMPACT THE AREA MONDAY AND TUESDAY. && .NEAR TERM /THROUGH FRIDAY/... WIND CHILL ADVISORY AND WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR THE POTOMAC HIGHLANDS AND HIGHER ELEVATIONS OF THE BLUE RIDGE. SFC LOW PRESSURE MOVES AWAY FROM THE REGION TODAY AS THE FIRST CANADIAN HIGH PRESSURE BUILDS IN. ALOFT...BROAD UPPER LVL TROUGH LIFTS NORTH AS ZONAL FLOW BUILDS IN BRIEFLY TONIGHT INTO FRIDAY. OUTSIDE OF CONTINUAL UPSLOPE SNOW SHOWERS TODAY...DRY CONDITIONS EXPECTED INTO FRI MORNING. AS THE TROUGH LIFTS NORTH...SHORTWAVE ENERGY EXTENDING ACROSS CENTRAL MD COULD TRIGGER SCT FLURRIES. BUT WITH SUCH A DRY AIR MASS IN THE LOWER LVLS...NOT ANTICIPATING ACCUM SNOW. GUSTY NW FLOW TODAY WITH THE AREA REMAINING SANDWICHED BETWEEN THE DEPARTING LOW AND APPROACHING HIGH. HIGH TEMPS WELL BELOW NORMAL...AND COMBINED WITH THE GUSTY WINDS...WIND CHILLS WILL HOVER IN THE SINGLE DIGITS AND TEENS. TONIGHTS LOWS WILL DROP INTO SINGLE DIGITS ABV ZERO AND THE TEENS...BUT WITH LIGHTER WINDS NOT ANTICIPATING ANOTHER WIND CHILL ADVISORY BEING NEEDED. AS THE HIGH MOVES OVERHEAD FRIDAY...RETURN FLOW WILL USHER IN SLIGHTLY WARMER TEMPS AND INCREASED MOISTURE. HIGHS ON FRIDAY WILL REACH NEAR FREEZING MOST PLACES. PCPN CHCS INCREASE FOR WESTERN AND SOUTHEASTERN AREAS WITH TWO LOW PRESSURE AREAS TO BE NOTED...LOW PRESSURE ORGANIZING OFF THE CAROLINA COAST AND PRE-FRONTAL SFC TROUGH SPLITTING THE WESTERN CWA. A LOT OF DRIER AIR NEEDS TO BE OVERCOME...WHICH WILL MINIMIZE PCPN POTENTIAL...AT LAST THRU 00Z. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... UPPER LVL TROUGH SWINGS SOUTH FRIDAY NIGHT...SENDING THROUGH A STRONG ARCTIC COLD FRONT. DEFINITE UPSLOPE SNOW SHOWERS WITH THE COLD FROPA...AND SCT SNOW SHOWERS NORTHERN HALF OF THE CWA WITH STRONG FORCING ALOFT. RIGHT NOW HAVE LESS THAN ONE INCH SNOW CENTRAL MD (THOUGH WOULD BE A QUICK BURST)...WITH 1-3 INCHES OF UPSLOPE SNOW...THE LATTER POTENTIALLY REQUIRING ANOTHER WINTER WX ADVISORY. THE BIGGER STORY WITH THIS SYSTEM IS THE ARCTIC BLAST IN THE WAKE AS A STRONG CANADIAN HIGH PRESSURE DIPS SOUTH OVER THE EASTERN US. 850MB TEMPS PLUMMET FROM -10 DEGREES CELSIUS 00Z SAT TO AROUND -20 DEGREES BY 12Z SAT. RESULTING TEMPS WILL SEE HIGHS IN THE SINGLE DIGITS OUT WEST...TO THE 20S EAST OF THE BLUE RIDGE. LOWS SAT NIGHT WILL SEE BELOW ZERO TO RIGHT ABV ZERO WEST OF THE BLUE RIDGE...TO SINGLE DIGITS ABV ZERO FOR THE REMAINDER OF THE CWA. IN ADDITION... STRONG NW WINDS EXPECTED WITH THE CAA...GUSTS AT LEAST 20- 30 KTS AND 30-40 KTS IN HIGHER ELEVATIONS (WIND ADVISORIES MAY BE NEEDED). CONCERNING WIND CHILLS...FRI NIGHT MOST LIKELY WILL NEED AN ADVISORY FOR ALLEGHENY FRONT AND HIGHER BLUE RIDGE ZONES. THE ADVISORY COULD CARRY THRU SAT. FOR SAT NIGHT...WIND CHILL WARNINGS MAY BE NEEDED FOR THE AFOREMENTIONED AREA...WITH WIND CHILL ADVISORIES LIKELY FOR THE REMAINING CWA AS THE ENTIRE AREA DROPS BELOW FREEZING. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... COLD SFC HIPRES WL BE OVER THE CWFA SUN. THE ONLY SAVING GRACE MAY BE THE RELATIVE LACK OF WIND...THX TO SUBSIDENCE. ITLL STILL BE A COLD DAY NONETHELESS...WITH A FRIGID START AND MAXT THEN STRUGGLING TO CLIMB THRU THE 20S. THE PRESENCE OF THIS COLD AMS ATOP US WL PLAY A ROLE IN THE MON-TUE FCST. MASSIVE TEMP CHGS RARELY OCCUR GRACEFULLY. THATS LOOKING TO BE THE CASE MON INTO TUE. WAA WL ENSUE SUN NGT-MON AS THE HIGH DRIFTS OFFSHORE AND SRN STREAM LOW PRESSURE TRACKS ACRS THE SRN PLAINS... EVENTUALLY ARRIVING IN THE CAROLINAS MON NGT. GDNC SUGGESTING VERY DIFFERENT STRENGTH SOLNS UP TO THIS POINT...AND LOPRES TRACK FCSTS VARY AS WELL BYD THIS POINT. REGARDLESS OF THESE SPECIFICS...THE LINGERING AMS WL BE COLD ENUF FOR PTYPE TO BE SNOW AT ONSET. AFTER THAT...THERE ARE PLENTY OF QUESTIONS LEFT TO ANSWER. GDNC FROM THE CURRENT CYCLE SUGGESTS THAT THE AMS OVER THE CWFA WL REMAIN COLD ENUF TO HOLD OFF ANY MIXING/RAIN TIL TUE. THE NEARER THE TRACK HOLDS TO THE CWFA...THE GREATER THE OPPORTUNITY FOR MIXED PTYPE ISSUES. THERES PLENTY OF ROOM FOR THIS FCST TO CHG...MOST LKLY SVRL TIMES. BY TUE NGT OR WED...THE RESULTANT /AND DEEPENING/ CSTL LOW WL BE DEPARTING THE MID ATLC...W/ ZONAL FLOW AND SEASONABLE TEMPS IN ITS WAKE. && .AVIATION /09Z THURSDAY THROUGH MONDAY/... GENERALLY EXPECTING VFR CONDITIONS LASTING THRU SAT NIGHT. ANY SNOW SHOWER WILL BRING A BRIEF REDUCTION IN CIGS AND VIS...MAINLY LOOKING AT KMRB/KIAD/KBWI/KMTN FRI NIGHT. GUSTY NW WINDS TODAY... GUSTING BTW 20-30 KTS. LIGHT SW WINDS ON FRI...INCRSG QUICKLY FRI NIGHT AND GUSTING BTW 25-35 KTS THRU SAT NIGHT. VFR SUN UNDER HIPRES. FLGT CONDS TO DETERIORATE BY MON AS LOPRES APPROACHES THE AREA. PTYPE ISSUES ABOUND...BUT MOST LKLY ITLL BE SNOW AT ONSET. && .MARINE... SCA IN EFFECT FOR ALL WATERS TODAY WITH NW WINDS GUSTING BETWEEN 20-25 KTS. AS THE HIGH BUILDS IN TONIGHT...WINDS DIMINISH...DROPPING BELOW SCA CRITERIA ON ALL WATERS BY FRI MORNING. SUB-SCA CONDITIONS FRI WITH SCA CRITERIA RETURNING IN THE WAKE OF A COLD FRONT FRI NIGHT. GALES LIKELY ON THE CHESAPEAKE BAY WATERS BY 12Z SAT MORNING...AND THE TIDAL POTOMAC BY MIDDAY SAT...LASTING THRU AT LEAST SAT EVENING AND POSSIBLY TILL SUN MORNING. WINDS WL DECREASE SUN AS HIPRES BLDS. MAY STILL HV SOME SCA CONDS IN THE MRNG...BUT THESE WL DIMINISH THRU THE DAY. SLY FLOW BY MON AS LOPRES APPROACHES. LKLY WL HV SNOW APPROACHING THE WATERS. PTYPE AFTER THAT UNCERTAIN. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...WIND CHILL ADVISORY UNTIL 10 AM EST THIS MORNING FOR MDZ501. WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR MDZ501. VA...WIND CHILL ADVISORY UNTIL 10 AM EST THIS MORNING FOR VAZ503- 504-507-508. WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR VAZ503. WV...WIND CHILL ADVISORY UNTIL 10 AM EST THIS MORNING FOR WVZ501- 503-505-506. WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR WVZ501- 503-505. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR ANZ530>534- 537>543. SMALL CRAFT ADVISORY UNTIL 8 PM EST THIS EVENING FOR ANZ535- 536. && $$ SYNOPSIS...SEARS NEAR TERM...SEARS SHORT TERM...SEARS LONG TERM...HTS AVIATION...SEARS/HTS MARINE...SEARS/HTS

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