Area Forecast Discussion
Issued by NWS Sterling, VA

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 KLWX 300119 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 919 PM EDT SAT AUG 29 2015 .SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE REMAINS OVER THE REGION THROUGH THE MIDDLE OF THE WEEK BEFORE WEAKENING LATE IN THE WEEK.
-- End Changed Discussion --
&& .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --
HIGH CLOUDS DISSIPATING/MOVING OUT OF THE AREA THIS EVENING. MOSTLY CLEAR CONDITIONS BY LATE TONIGHT. HOWEVER...HIGHER SFC MOISTURE COMPARED TO YESTERDAY WILL RESULT IN A WARMER NIGHT... LOWS IN THE 60S XCPT L70S IN THE CITIES AND ALONG THE BAY. LGT FOG LIKELY IN SHELTERED VALLEYS AND PORTIONS OF THE PIEDMONT.
-- End Changed Discussion --
&& .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
-- Changed Discussion --
SUNDAY SAME STORY DIFFERENT DAY - HIGH PRES RMNS OVR THE AREA. HIGHS 85-90. LOW 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.
-- End Changed Discussion --
&& .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 /01Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
VFR CONDS XPCTD TNGT AND SUN. MVFR VSBYS LIKELY AT CHO/MRB...MIFG AT IAD. 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.
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
SLY CHANNELING SURGE WITH GUSTS TO 20 KT CURRENTLY OVER CNTRL AND NRN MD BAY WATERS WILL CONTINUE TO LIFT NORTH THROUGH THE REST OF THE EVENING. MARINE WEATHER STATEMENT FOR THESE GUSTS THROUGH 10PM. 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.
-- End Changed Discussion --
&& .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ UPDATE...JACKSON PREVIOUS...WOODY!/ADS/IMR

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