FXUS61 KRLX 050801
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
400 AM EDT SUN JUL 5 2009
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL SPREAD RAIN INTO THE REGION THROUGH 
SUNDAY. HIGH PRESSURE BUILDS IN FOR DRY WEATHER MONDAY THROUGH MID 
WEEK. ANOTHER FRONT ARRIVES LATER IN THE WEEK OR NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
WHILE THE WEAK SURFACE LOW SLOWLY EDGES EASTWARD...AT 7Z IT WAS OVER 
SOUTHERN ILLINOIS...THE MAIN RAIN SHIELD IS WELL IN ADVANCE OF THE 
FRONT AND THE UPPER TROUGH.  BUT IT IS IN THE BEST 850 MB JET REGION 
ON THE EAST SIDE OF THE UPPER TROUGH.  AS THE 850 MB JET SHIFT TO 
THE EAST SO WITH THE PRECIPITATION.  SO HAVE HELD ON TO SOME HIGH 
POPS EARLY TODAY ACROSS THE SOUTH...BUT ONCE THE 850 MB JET AND 
ASSOCIATED ISENTROPIC LIFT SHIFT EAST...EXPECT TO SEE THE CHANCES 
FOR RAIN DROP BACK PRETTY QUICKLY THERE AFTER.  BY LATE THIS 
AFTERNOON...WILL SEE THE SURFACE LOW REFORMING EAST OF THE MOUNTAIN 
ALONG A STALLED OUT FRONTAL BOUNDARY.  ONCE THIS LOW REFORMS AND THE 
UPPER TROUGH AXIS PASSES...SHOULD SEE THE CHANCES FOR RAIN DROP 
PRETTY QUICKLY THIS EVENING.  BUT WITH THE WEAK INITIAL SURFACE LOW 
TO THE WEST AND THE ABUNDANT LOW LEVEL MOISTURE STILL AROUND SHOULD 
SEE LOTS OF CLOUDS PERSIST INTO THE EVENING HOURS BEFORE THE CLOUDS 
BREAK UP.  ONCE THE CLOUDS DO BREAK SHOULD SEE QUITE A BIT OF FOG 
FORM...ESPECIALLY FOR AREAS THAT GET RAIN.
FOR TEMPERATURES TODAY...STAYED WELL BELOW THE GUIDANCE AS THE 
CLOUDS AND LIGHT RAIN SHOULD KEEP TEMPERATURES DOWN.  THE ONLY 
EXCEPTION COULD BE PKB AND AREAS WEST WHERE SOME  SUNSHINE COULD BE 
AROUND TO PUSH READINGS HIGHER. TONIGHT SHOULD SEE GOOD RADIATIVE 
COOLING CONDITIONS ONCE THE CLOUDS BREAK.  BUT THEN WITH THE SURFACE 
MOIST SHOULD SEE FOG DEVELOP WHICH COULD HOLD TEMPS UP A DEGREE OR 
TWO SO LEANED TOWARD THE SLIGHTLY WARMER MET.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MODELS SHOW HIGH PRESSURE BUILDING OVER THE REGION ON 
MONDAY...PROVIDING DRY WEATHER. MODEL DIFFERENCES THEN BEGIN TO 
APPEAR WITH HANDLING OF A FRONTAL BOUNDARY FOR MID WEEK. GFS KEEPS 
THE BOUNDARY TO THE NORTH WITH JUST SOME MOISTURE EDGING INTO THE 
NORTHERN COUNTIES. NAM WOULD BRING THE BOUNDARY OVER THE FORECAST 
AREA. SREF AND ECMWF KEEP THE BOUNDARY OUT OF THE REGION. BASED ON 
ENSEMBLES...WILL STAY WITH CURRENT FORECAST AND KEEP DRY FOR NOW. 
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
WENT MOSTLY WITH ECMWF PER HPC AND ISC.  NW FLOW REGIME PERSISTS 
OVERALL THROUGH THE PERIOD WITH UPPER RIDGE MAINLY OVER SOUTHERN 
ROCKIES INTO SOUTHERN PLAINS.  CONTINUED WITH DRY SOLN FOR NOW WITH 
VIGOROUS SHORT WAVE TROUGH MOVING SE...MOST OF ITS ENERGY PASSING NE 
OF THE FCST AREA.  HIGH PRESSURE BRINGS DRY WEATHER FOR THE 
BALANCE OF THE WORK WEEK AS HEIGHTS BUILD SOMEWHAT.  NEXT FRONT 
APPROACHES SAT DAY 7 PER ECMWF.
TEMPERATURES WERE MOSTLY A BLEND OF ONGOING...GFS AND HPC...WITH THE 
DRY WEATHER ACTUALLY ALLOWING FOR HIGHS MORE TYPICAL OF SUMMER 
DESPITE THE NW FLOW ALOFT...BECAUSE THE HEIGHTS COME UP.  THE NIGHTS 
REMAIN TOLERABLE FOR THIS TIME OF YEAR EXCEPT FRI NT AHEAD OF THE 
NEXT COLD FRONT.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
COMPLEX WEATHER SYSTEM IS PUSHING RAIN ACROSS THE REGION AT THIS
TIME. THE SURFACE LOW IS NEAR SPARTA ILLINOIS AND IS TRACKING OFF
TO THE EAST...WITH A WARM FRONT STRETCHING EASTWARD ACROSS KY.
NORTH OF THE FRONT...THE BEST OVERRUNNING IS SETTING UP ACROSS SRN
OHIO INTO WV AND IS BEING ENHANCED BY AN UPPER LEVEL SHORTWAVE. AT
THIS TIME...CEILINGS ARE STILL VFR...BETWEEN 4K AND 7KT FT. THEY
COULD FLUCTUATE DOWN TO AROUND 2500 FT IN THE HEAVIER SHOWERS THAT
WILL MOVE ACROSS HTS/CRW/BKW THROUGH 11Z. ELSEWHERE...CEILINGS
SHOULD VARY LITTLE AS THE BEST RAIN REMAINS TO THE SOUTH...JUST
NORTH OF THE WARM FRONT.
BY AROUND 12Z...THE SURFACE LOW SHOULD BE MOVING ACROSS CENTRAL
KY...BUT WITH THE UPPER SUPPORT SWING THROUGH...WILL BEGIN TO SEE
THE SURFACE LOW REDEVELOP EAST OF THE MOUNTAINS AND THIS FEATURE
WILL THEN RACE OFF TO THE EAST...PUSHING THE FRONTAL BOUNDARY BACK
TO THE SOUTH. THIS WILL CAUSE THE SHOWER ACTIVITY TO DIMINISH
BETWEEN 12Z AND 18Z...BUT AS THE FLOW TURNS MORE OUT OF THE EAST
AND NORTHEAST...EXPECT CEILINGS TO FALL DOWN TO MVFR
LEVELS...ESPECIALLY IN THE MOUNTAINS AND SOUTHERN COAL FIELDS.
DRIER AIR TO THE NORTHWEST WILL SLOWLY ERODE THE CLOUDS AWAY
THIS EVENING AS THE UPPER TROUGH AXIS AT 850 MB AND 700 MB SLOWLY
SAGS SOUTHWARD. ONCE PAST...THE LOW LEVEL MOISTURE WILL BEGIN TO
THIN...ALLOWING THE SKY TO CLEAR...BUT ONCE IT DOES...FOG SHOULD
FORM BEHIND PRETTY QUICKLY...ESPECIALLY IN LOCATIONS THAT RECEIVE
THE RAIN.
AFTER 06Z MONDAY...
IFR FOG EXPECTED OVERNIGHT MONDAY ALONG RIVER VALLEYS AND THE 
SOUTHERN AREAS THAT RECEIVED RAIN.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ESS/RPY
NEAR TERM...ESS
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...ESS