Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 291848 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 248 PM EDT SAT AUG 29 2015 .SYNOPSIS... HIGH PRESSURE REMAINS OVER THE REGION THROUGH SUNDAY AND THEN SLIDES OFFSHORE FOR THE WEEK AHEAD. && .NEAR TERM /TONIGHT/... HIGH PRES RMNS OVR THE AREA. PRNSTLY CU FORMING OVR THE MTNS...LOW CHCS THAT ANY OF THESE WL FORM INTO A SHWR/TSTM. OVRNGT NOT QUITE AS COOL AS THE PRVS FEW NGTS W/ LOWS IN THE 60S XCPT L70S IN THE CITIES AND ALONG THE BAY. LGT FOG MAY FORM IN THE CENTRAL SHEN VLLY AFTR MDNGT. && .SHORT TERM /SUNDAY/... TMRW SAME STORY DIFFERENT DAY - HIGH PRES RMNS OVR THE AREA. HIGHS 85-90. A LTL BETTER CHC OF RW/TRW TMRW...ESPECIALLY OVR THE MTNS...BUT AT THIS TIME OF YR UPR LVL WIND FIELD IS GNRLY PRETTY LGT...AS IS THE CASE SUNDAY. HENCE SVR THREAT IS NIL. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... BY SUNDAY NIGHT...TROUGH IN THE NORTHERN STREAM INVOF THE EASTERN GREAT LAKES WILL PROVIDE THE WEAKNESS FOR THE CLOSED LOW WHICH HAS BEEN RESIDING ON THE CENTRAL GULF COAST TO LIFT NE. WHILE DIURNAL CONVECTION OVER THE HIGH TERRAIN WILL BEGIN TO WEAKEN DURING THE EVENING...HAD TO CONTINUE LOW END POPS THROUGH THE NIGHT AS THE TROUGH APPROACHES FROM THE SOUTHWEST. LOWS WILL BE IN THE 60S WITH LOWER 70S E OF I-95. THERE ARE SOME SLIGHT TIMING DIFFERENCES...BUT THE TROUGH SHOULD LIFT ACROSS THE AREA DURING THE MORNING TO MIDDAY HOURS...SHEARING OUT AS IT INTERACTS WITH THE NORTHERN STREAM. AT THE MINIMUM...MONDAY WILL BE A MOSTLY CLOUDY INTERRUPTION TO OUR HIGH PRESSURE-DOMINATED WEATHER PATTERN. LOW LEVEL MOISTURE AND FORCING WILL BE POOR...BUT ELECTED TO LEAVE AT LEAST SLIGHT CHANCE POPS ACROSS THE ENTIRE AREA. THUNDER CHANCES WILL BE MINIMAL WITH THIS FEATURE. ALSO SHADED HIGH TEMPERATURES A LITTLE LOWER DUE TO THE CLOUDS...MAINLY IN THE MID 80S. LATE SUMMER PATTERN RESUMES MONDAY NIGHT INTO TUESDAY...AND IF ANYTHING...MID/UPPER RIDGING WILL BUILD FURTHER OVER THE EASTERN CONUS. THIS WILL MEAN RISING TEMPERATURES...WITH MANY AREAS NEAR OR ABOVE 90 FOR HIGHS. WITHOUT A PROMINENT TRIGGER PRESENT AND POOR MID- LEVEL LAPSE RATES...ANY DIURNAL CONVECTION WILL BE CONFINED TO THE MOUNTAINS. TUE NGT-SAT: HIGH PRES WILL MOSTLY DOMINATE CONDITIONS DURING THIS PERIOD...WITH SOME UPPER LEVEL SHORTWAVES THAT WILL MOVE THROUGH OR NEAR OUR AREA. 00Z ECMWF KEEPS OUR CWA DRIER THAN THE 12Z GFS...WITH BOTH MODELS BRINGING PRECIP OVER OR NEAR OUR CWA NEXT SAT. KEPT A CHANCE OF SHOWERS AND TSTMS DURING THE LATE AFTN/ERLY EVE EACH DAY BUT MAJORITY OF TIME WL BE DRY. TEMPS WILL BE FIVE TO TEN DEGREES ABOVE NORMAL FOR ERLY SEPT. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... VFR CONDS XPCTD TNGT AND SUN. LGT FOG IS PSBL AT CHO/MRB. UPPER DISTURBANCE PASSES OVER SUNDAY NIGHT-MONDAY...BUT VFR CONDITIONS SHOULD PREVAIL AND ANY ISOLATED SHOWER SHOULD BE LIGHT. TUESDAY MORNING WILL PROBABLY REPRESENT THE BETTER OPPORTUNITY FOR MORNING BR AT MRB/CHO AS SKIES CLEAR. ANY DIURNAL STORMS TUESDAY AFTERNOON LIKELY STAY WEST OF TERMINALS. && .MARINE... WINDS ARE XPCTD TO RMN BLO SCA VALUES MAJORITY OF NEXT 24 HRS. THERE MAY BE A PD THIS EVE WHEN SRLY CHANNELING WL PUSH WINDS INTO THE UPR TEENS. IF SO A 3 HR MWS OR SCA MAY NEED TO BE ISSUED FOR PORTIONS OF THE BAY. TROUGH OF LOW PRESSURE TO THE NORTH WILL TIGHTEN THE PRESSURE GRADIENT SUNDAY EVENING...AND WHEN COMBINED WITH SOUTHERLY CHANNELING THERE COULD BE A BRIEF WINDOW FOR SCA CONDITIONS. HOWEVER HAVE LIMITED FORECAST TO 15 KT FOR NOW DUE TO LOW CONFIDENCE. WESTERLY FLOW 5-10 KT MONDAY WILL BECOME LIGHTER AND MORE VARIABLE MONDAY NIGHT AND TUESDAY AS HIGH PRESSURE IS REESTABLISHED. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ PRODUCTS...WOODY!/ADS/IMR

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