Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 270754 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 354 AM EDT SAT SEP 27 2014 .SYNOPSIS... HIGH PRESSURE OVER ONTARIO WILL REMAIN OVER THE REGION THROUGH LATE SUNDAY. A LOW PRESSURE SYSTEM WILL FORM OVER THE SOUTHEAST GULF COAST STATES SUNDAY NIGHT...AND MOVE TO THE NORTHEAST TOWARDS THE CAROLINAS MONDAY AND TUESDAY. HIGH PRESSURE WILL BUILD OVER MAINE AND ATLANIC CANADA IN THE LATTER PART OF THE WEEK. && .NEAR TERM /TODAY/... AS OF 07Z...1026MB SFC HIGH REMAINS OVER THE EASTERN GREAT LAKES. HOWEVER THERE IS A WEAK PRESSURE GRADIENT (1025MB ACROSS THE CWA)...SO FEW SITES ARE REPORTING WIND. IN SPITE OF CLEAR/CALM CONDITIONS...LITTLE FOG HAS FORMED SO FAR (GROUND IS LESS MOIST AFTER A SUNNY DAY). THE HIGH WILL PERSIST OVER SRN ONTARIO THROUGH THIS AFTERNOON WITH LIGHT NORTH FLOW RESUMING AFTER SUNRISE FOR THE CWA. NLY FLOW IS ACTUALLY WARM AIR ADVECTION TODAY AS CONTINENTAL AIR WRAPS AROUND THE GREAT LAKES HIGH (IT WAS IN THE MID 90S FRIDAY IN MANITOBA). MAX TEMPS GENERALLY AROUND 80F TODAY. && .SHORT TERM /TONIGHT THROUGH SUNDAY/... THE HIGH DRIFTS EAST TO NEW ENGLAND TONIGHT...VEERING OUR WIND TO AN ONSHORE FLOW INTO SUNDAY. QUIET WEATHER THROUGH THE WEEKEND WITH CONTINUED ABOVE NORMAL TEMPS. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... LAST NGT I DESCRIBED THE XTND WX PATTERN AS "NEBULOUS" AND THAT`S STILL HOW IT LOOKS ERLY THIS SAT MRNG. GFS SHOWS HIGH PRES MOVG AWAY FM THE RGN SUN NGT...AN E-W RUNNING CD FNT STRETCHING ACROSS ERN CANADA..AND AN ATTEMPT AT A WV FORMING OVR THE GULF STATES. BY TUE THE CD FNT DOES NOT MAKE IT FURTHER S THAN NRN NEW ENGLAND...PARTIALLY IN RESPONSE TO INCRSG SRLY FLOW OVR THE UPR MIDWEST AS AN AREA OF LOW PRES MOVES INTO THE DAKOTAS. THE GULF LOW NEVER REALLY GETS ORGANIZED INTO ANYTHING..BUT THERE IS AN AREA OF MOISTURE ASSO W/ IT THAT PUSHES INTO THE MID ATLC. AFTR MIDWEEK THE GFS HAS A 1033 HIGH MOVG OVR NRN ME. IF IT DOES WORK OUT THIS WAY I AM THINKING THERE WL BE A PBSLTY THAT A CAD WEDGE WL DVLP...KEEPING THE MID ATLC CLDY THU AND FRI. THIS IS STILL MANY DAYS AWAY...AND IT IS QUITE HARD TO DEFINITIVELY STATE SUCH A SET UP WL DVLP FIVE DAYS OUT...BUT THIS IS A PSBLTY. NAM ONLY GOES TO 00Z TUE...BUT ALSO SHOWS THE E-W FNT RMNG OVR NRN NEW ENGLAND..THE HIGH MOVG OUT INTO THE ATLC...AND A WEAK SHRT WV MOVG UP FM THE GULF SATES. ERUO IS SIMILAR BUT SHOWS AN UPR LVL SHORT WV DESCENDING FM THE NRN STREAM TUE...FORMING A SMALL CUT OFF LOW OVR ERN PA WED. NOT QUITE SURE HOW THIS WOULD INTERACT W/ THE GULF MOISTURE - ECM SORT OF SHOWS IT BEING SHUNTED OUT TO SEA FM THE CAROLINAS. WHAT IS ACTUALLY OF GRTR INTEREST...NOT NEBULOUS...BUT BYND THE SCOPE OF THIS FCST IS AN UPR LOW THAT THE ECM PROJECTS TO FORM OVR ERN CANADA NEXT WKND W/ A TROF SETTING UP TO OUR W. IF THIS HAPPENS IT LOOKS LK FLOW COULD COME OUT OF THE GULF..BRINGING US A PD WETNESS IN ERLY OCT. THE XTND FCST - HIGHS IN THE 70S MON-FRI..LOWS IN THE 50S XCPT L60S IN THE CITIES AND ALONG THE BAY. MON/TUE LOOK TO BE M CLDY W/ LOW CHC POPS. WED/THU SHOULD BE DRY. IF DAMMING SITUATION DOES DVLP WL HV LOW CHC POPS TO END THE WK...BUT IT IS OFTEN THE CASE IN CAD EVENTS THAT THERE IS XTNSV CLD CVR BUT LTL-TO-NO PCPN. && .AVIATION /07Z SATURDAY THROUGH WEDNESDAY/... LESS FOG THIS MORNING THAN LAST. HIGH PRESSURE/VFR PREVAILS THROUGH MONDAY. LIGHT NLY FLOW TODAY BECOMES ONSHORE TONIGHT. IT IS PSBL BUT NOT CERTAIN THAT SUB-VFR CIGS COULD OCCUR MON/TUE. && .MARINE... HIGH PRESSURE LINGERS OVER THE EASTERN GREAT LAKES THROUGH TODAY WITH LIGHT NLY FLOW CONTINUING UNTIL IT VEERS TO ONSHORE FLOW TONIGHT AS THE HIGH SHIFTS EAST. NEXT CHC FOR SCA WINDS WILL BE MON NIGHT INTO TUE AS LOW PRES PULLS AWAY FM CAPE HATTERAS. && .TIDES/COASTAL FLOODING... DEPARTURES INCREASING ACROSS THE WATERS...WATER LEVELS ARE EXPECTED TO APPROACH...BUT REMAIN BELOW MINOR FLOOD THRESHOLDS DURING THE LESSER HIGH TIDE THROUGH MID-MORNING. WINDS BECOME ONSHORE THROUGH THE DAY TODAY...AND SHOULD ALLOW MINOR COASTAL FLOODING AT SENSITIVE LOCATIONS FOR THE LATE AFTERNOON/EVENING PREFERRED HIGH TIDE. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ PRODUCTS...BAJ/WOODY!

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