FXUS61 KRNK 061909
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
309 PM EDT MON OCT 6 2008

.SYNOPSIS...
COOL HIGH PRESSURE BUILDS ACROSS THE MID ATLANTIC REGION TONIGHT
THROUGH TUESDAY. THE HIGH SHOULD BEGIN TO WEAKEN AND SLIDE
OFFSHORE BY MIDWEEK AHEAD OF A COMPLEX LOW PRESSURE SYSTEM THAT
WILL AFFECT THE AREA WEDNESDAY THROUGH FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
HIGH PRESSURE WILL BUILD DOWN THE LEE OF THE APPALACHIANS
TONIGHT. THIS WILL BRING THE LOW LEVEL WINDS AROUND TO THE
NORTHEAST THEN EAST AND INCREASE THE MOISTURE BEING BANKED UP
AGAINST THE SOUTHERN BLUE RIDGE. THE NAM IS STILL MORE AGGRESSIVE
WITH THE AMOUNT OF CLOUD COVER GENERATED AFTER 06Z. THE GFS STAYS
DRIER. HAVE BASED THE CLOUD COVER ON A COMPROMISE...SIMILAR TO THE
CANADIAN...WITH STRATUS DEVELOPING SOUTH OF ROANOKE AND FILLING IN
DURING THE EARLY MORNING HOURS.

RAISED MINIMUM TEMPERATURES A FEW DEGREES ABOVE GUIDANCE FOR
TONIGHT. THE MAV MAY BE TOO COOL...ESPECIALLY IN THE SOUTHWEST
SINCE IT IS NOT EXPECTING MUCH CLOUD COVER.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
HIGH SHOULD BRIDGE DOWN EAST OF THE BLUE RIDGE TUESDAY WITH THE
LOW LEVEL FLOW TURNING MORE SE UNDER STRONG S/W RIDGING ALOFT.
THIS COMBO WITH HEATING SHOULD SUPPORT GRADUALLY MIXING OUT ANY
MORNING LOW CLOUDS WITH ONLY THE FAR SW POSSIBLY HOLDING A LOW
DECK INTO THE AFTERNOON. AIRMASS THOUGH IS PRETTY COOL AND IF
CLOUDS GET STUCK COULD BE A RATHER CHILLY DAY SIMILAR TO THE QUITE
COOL MET MOS. SINCE EXPECTING MORE SUN LEANED TEMPS TOWARD THE
WARMER MAV MOS OR SIMILAR TO THE ENSEMBLES GIVEN SUCH A LARGE
SPREAD IN TUE HIGHS.


&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
FOR WEDNESDAY...UPPER LOW TO THE WEST WILL BEGIN TO PUSH ITS WARM
ADVECTION/ISENTROPIC LIFT PRECIP SHIELD TOWARD THE AREA AS RIDGING
SLIPS OFFSHORE. MODELS CONTINUE TO SPLIT ON THE SPEED OF THE
SYSTEM...WITH THE 12Z CMC/GFS THE FASTEST AND THE 12Z NAM THE
SLOWEST. LEANING THE FORECAST TOWARD THE 09Z SREF/00Z
ECMWF...WHICH SITUATES AREA INTO OVERRUNNING FOR WEDNESDAY. HAVE
INCREASED CLOUDS AND BROUGHT THE SLIGHT CHANCE FURTHER EAST INTO
THE FOOTHILLS. DRY AIRMASS SHOULD DELAY THE ONSET OF RAIN. FURTHER
WEST BROUGHT LOW CHANCE IN.

WEDNESDAY NIGHT INTO THURSDAY THE SFC LOW DEVELOPS UNDER THE UPPER
LOW ACROSS GA/SC. INFLUX OF MOISTURE ARRIVES IN FULL...ALTHOUGH
SHOULD SEE HEAVIER PRECIP OVER THE SOUTHEAST COAST INTO INTERIOR
GA. WILL HAVE LIKELY POPS OVER THE SOUTH TO 40-50 NORTH INTO
THURSDAY MORNING...THEN DECREASE SOMEWHAT TO JUST CHANCE THU
AFTERNOON-THU NIGHT AS THE LOW PUSHES INTO THE ATLANTIC. APPEARS
FRONT MAY HANG UP OVER THE SOUTHEAST FRIDAY-SATURDAY...AND WILL
KEEP SLIGHT CHANCE SHOWERS IN FOR THE SOUTHEAST CWA INTO SATURDAY
BEFORE DRY WEDGE OF HI PRESSURE NOESES IN FROM THE NORTHEAST SUN-
MON. ANOTHER FRONT LOOKS TO ARRIVE BY THE END OF DAY 7.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
HIGH PRESSURE WILL BUILD DOWN THE EAST COAST TONIGHT AND TUESDAY.
THIS WILL BRING THE LOW LEVEL WINDS AROUND TO THE SOUTHEAST BY
TUESDAY MORNING AND BRING INCREASING MOISTURE TO THE EAST SIDE OF
THE APPALACHIANS OVERNIGHT. STRATUS IS EXPECTED TO DEVELOP ALONG
AND EAST OF THE SOUTHERN BLUE RIDGE WITH IFR CEILINGS AFTER 06Z
THAT LIFT TO MVFR CEILINGS AFTER 15Z.

AT THIS TIME DON'T EXPECT THE LOWER CLOUDS TO GET INTO ROA...LYH OR DAN
BUT HAVE MVFR CONDITIONS IN AT BLF AND LWB.

RAIN WILL BE MOVING INTO THE AREA BY THURSDAY AND THEN LINGERING
INTO FRIDAY AS SURFACE LOW MOVES FROM THE CENTRAL PLAINS ACROSS
THE SOUTHEAST UNITED STATES.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.

&&

$$
SYNOPSIS...JH/WP
NEAR TERM...AMS
SHORT TERM...JH/WP
LONG TERM...JH/WP
AVIATION...AMS/JH



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