Area Forecast Discussion
Issued by NWS Sterling, VA

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FXUS61 KLWX 241357
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
957 AM EDT FRI OCT 24 2014

.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVERHEAD THROUGH SATURDAY. A REINFORCING
COLD FRONT WILL PASS THROUGH THE REGION LATE SATURDAY NIGHT INTO
SUNDAY BEFORE HIGH PRESSURE RETURNS FOR MONDAY. THE HIGH WILL MOVE
OFF THE COAST DURING THE MIDDLE PORTION OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
LOW PRESSURE LOCATED ACROSS THE NORTHERN ATLANTIC WILL CONTINUE TO
MOVE EASTWARD AND AWAY FROM THE MID ATLANTIC COAST TODAY. A TIGHT
PRESSURE STILL EXISTS ACROSS THE EASTERN HALF OF THE LOOKOUT AREA.
NW WINDS 15-20 MPH WITH GUSTS UP TO 25 MPH ARE POSSIBLE TODAY IN
THIS AREA. WINDS SHOULD SUBSIDE BY LATE AFTERNOON AS THE GRADIENT
MOVES EASTWARD.

A SHORTWAVE TROUGH WILL CONTINUE TO DIG INTO THE TN VALLEY THIS
MORNING AND MOVE ACROSS THE REGION LATER TODAY. MID-HIGH LEVEL
CLOUDS AHEAD OF THE SYSTEM WILL STREAM INTO THE MID ATLANTIC
TODAY. DRY WEATHER IS EXPECTED TODAY WITH FCST MAX TEMPS REACHING
THE MID TO UPPER 60S.

PREV DISCUSSION...
THIS FEATURE WILL KEEP ITS INFLUENCES AWAY FROM THE MID-ATLC
BUT WILL HELP TO USHER-IN THE MORE CALMING EFFECT OF AN UPPER
MIDWEST HIGH. AFTER THE SFC FLOW DISSIPATES POST-SUNSET
TONIGHT...DEWPOINTS WILL SLOWLY REBOUND AGAIN INTO THE 40S...FOR
ANOTHER REL MILD TEMP RANGE FOR OUR OVERNIGHT LOWS. APPLIED A
BIAS-CORRECTED MET/MEX FOR TODAY`S HIGH/LOW TEMP GRIDS. ALSO
MODIFIED WINDS IN THE NEAR/SHORT TERMS W/ NEWER HI-RES WRK
GUIDANCE.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE NOSE OF A POTENT UPPER LEVEL JET WILL MAKE A QUICK ENTRANCE ON
SAT...SLAMMING UP AGAINST THE EXITING UPPER LEVEL JET FROM THE
OFFSHORE LOW. THIS FAST UPPER NW FLOW WILL START TO BRING IN THE
CLOUD COVER TO THE MTNS ON SAT...BUT LEAVE THE REMAINDER OF THE AREA
FAIRLY DRY AND CLEAR UNTIL LATER IN THE EVE. BEING ON THE RIGHT-EXIT
DOWNWARD MOTION SIDE OF THE UPPER JET WILL KEEP THE AREA DRY HEADING
INTO THE WEEKEND. WEAK BUT STEADY DOWNSLOPING FLOW MAY HELP BRING
TEMPS UP A FEW MORE DEG...PEAKING IN THE M-U60S - POSSIBLY JUST
ABOVE 70F FOR SAT AFTN.

LOW PRESSURE WILL TRACK THROUGH EASTERN CANADA SATURDAY NIGHT AND
EVENTUALLY TOWARD NOVA SCOTIA ON SUNDAY. THE COLD FRONT ASSOCIATED
WITH THIS SYSTEM WILL PASS THROUGH OUR REGION LATE SATURDAY NIGHT
INTO SUNDAY. LITTLE FORCING AND LITTLE MOISTURE WILL BE ASSOCIATED
WITH THE FRONT. THEREFORE...MOST AREAS WILL REMAIN DRY WITH JUST
A FEW CLOUDS NEAR THE BOUNDARY. THERE MAY BE A FEW SHOWERS ALONG
AND WEST OF THE ALLEGHENY FRONT DUE TO AN UPSLOPE FLOW...BUT EVEN
ACROSS THESE AREAS ANY PRECIPITATION WILL BE LIGHT. LEANED TOWARD
THE WARMER GUIDANCE SATURDAY NIGHT DUE TO SOME CLOUD COVER AND A
GRADIENT WIND HOLDING OFF ANY RADIATIONAL COOLING. MIN TEMPS ARE
FORECAST TO RANGE FROM NEAR 40 ALONG THE RIDGE TOPS OF THE POTOMAC
HIGHLANDS TO THE LOWER AND MIDDLE 50S IN DOWNTOWN WASHINGTON AND
BALTIMORE.

HIGH PRESSURE WILL APPROACH THE REGION SUNDAY BEHIND THE COLD
FRONT...BUT THE GRADIENT WILL REMAIN STRONG BETWEEN THE APPROACHING
HIGH AND THE DEPARTING COLD FRONT...RESULTING IN BREEZY CONDITIONS.
NORTHWEST WINDS WILL GUST AROUND 20 TO 30 MPH DURING THE LATE
MORNING AND AFTERNOON HOURS. SUNSHINE AND A DOWNSLOPING FLOW WILL
OFFSET ANY WEAK COLD AIR ADVECTION...ALLOWING FOR MAX TEMPS TO BE
ABOVE CLIMO. OF COURSE...THE MILD CONDITIONS MAY BE OFFSET BY THE
GUSTY WINDS. LEANED TOWARD THE WARMER SIDE OF GUIDANCE...WITH MAX
TEMPS FORECAST TO RANGE FROM THE 50S IN THE MOUNTAINS TO THE MIDDLE
70S ACROSS CENTRAL VIRGINIA INTO SOUTHERN MARYLAND. HIGH PRESSURE
WILL BUILD OVERHEAD SUNDAY NIGHT...CAUSING WINDS TO DIMINISH.
LIGHT WINDS...MAINLY CLEAR SKIES AND DRY CONDITIONS WILL PROVIDE A
GOOD SETUP FOR RADIATIONAL COOLING. THEREFORE...MIN TEMPS SUNDAY
NIGHT WILL BE CHILLY...RANGING FROM THE MIDDLE 30S ACROSS NORTHERN
MARYLAND AND FOR LOCATIONS NEAR AND WEST OF THE BLUE RIDGE
MOUNTAINS...TO THE MIDDLE 40S IN DOWNTOWN WASHINGTON AND BALTIMORE.
FROST IS POSSIBLE ACROSS MANY LOCATIONS OVERNIGHT SUNDAY.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL MOVE OFF THE COAST MONDAY AND TUESDAY. A
SOUTHERLY WIND WILL ALLOW FOR MILDER CONDITIONS DURING THIS TIME.
A COLD FRONT WILL PASS THROUGH THE AREA TUESDAY NIGHT INTO
WEDNESDAY...AND IT WILL STALL OUT NEARBY FOR LATER WEDNESDAY AND
THURSDAY. UNSETTLED CONDITIONS ARE POSSIBLE DURING THIS TIME...BUT
CERTAINTY REMAINS LOW THIS FAR OUT IN THE FORECAST PERIOD.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
ANOTHER BREEZY AFTN TODAY BUT A TIER LOWER IN TERMS OF PEAK
GUSTS...WHERE 15-25KT WILL BE FAIRLY COMMON FROM AFTER SUNRISE.
SEVERAL MORE HEADING INTO THE DAYTIME HRS...OF THE STEADY BREEZE
TODAY. WINDS WILL THEN QUICKLY DROP OFF TOWARD SUNSET. HIGH
PRESSURE CONTINUE STRENGTHENING OVER THE AREA INTO SAT.

NORTHWEST WINDS WILL GUST AROUND 20 TO 25 KNOTS SUNDAY. WINDS WILL
DIMINISH AROUND SUNSET SUNDAY EVENING...AND LIGHT WINDS ARE
EXPECTED OVERNIGHT AS HIGH PRESSURE BUILDS OVERHEAD. SOUTH-
SOUTHWEST WINDS ARE EXPECTED MONDAY AND TUESDAY AS HIGH PRESSURE
MOVES OFF THE COAST. VFR CONDITIONS ARE EXPECTED SUNDAY THROUGH
TUESDAY.

&&

.MARINE...
A WEAK UPPER LOW WILL MEANDER JUST OFF THE COAST INTO THE LATE
NIGHT HRS TONIGHT...KEEPING BREEZY CONDITIONS OVER THE AREA UNTIL
LATER THIS EVE. SCA CONTINUED FOR ALL THE WATERS TODAY.

A REINFORCING COLD FRONT WILL PASS THROUGH THE WATERS LATE
SATURDAY NIGHT INTO SUNDAY. A SMALL CRAFT ADVISORY MAY BE NEEDED
FOR PORTIONS OF THE WATERS SATURDAY NIGHT. A SMALL CRAFT ADVISORY
WILL LIKELY BE NEEDED FOR NORTHWEST WINDS BEHIND THE FRONT SUNDAY
INTO SUNDAY NIGHT.

HIGH PRESSURE WILL BUILD OVERHEAD LATE SUNDAY NIGHT INTO MONDAY
BEFORE MOVING OFF THE COAST LATER MONDAY THROUGH THE MIDDLE
PORTION OF NEXT WEEK. A SOUTHERLY FLOW WILL INCREASE DURING THIS
TIME. A SMALL CRAFT ADVISORY MAY BE NEEDED FOR PORTIONS OF THE
WATERS TUESDAY AND WEDNESDAY.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR
     ANZ530>543.

&&

$$
SYNOPSIS...BJL
NEAR TERM...GMS/HAS
SHORT TERM...BJL/GMS
LONG TERM...BJL
AVIATION...BJL/GMS
MARINE...BJL/GMS







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