807
FXUS61 KPBZ 130810
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
410 AM EDT TUE AUG 13 2013
.SYNOPSIS...
AFTER A COLD FRONT BRINGS SHOWERS TODAY...COOL AND DRY CONDITIONS
CAN BE EXPECTED FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
TWO MAIN AREAS OF RAIN CONTINUE TO PUSH TO THE EAST. NORTHERNMOST
TIER OF COUNTIES WILL HAVE SOME STRONG STORMS OVER THE NEXT FEW
HOURS...WHILE HEAVY RAIN WILL CONTINUE SOUTH OF THE MASON-DIXON
LINE. ALTHOUGH RAIN RATES ACROSS THE SOUTH HAVE DIMINISHED
CONSIDERABLY FROM WHAT THEY WERE AT MIDNIGHT...WILL CONTINUE THE
FLASH FLOOD WATCH UNTIL THE RAIN CLEARS THE REGION. IN BETWEEN THESE
TWO AREAS OF RAIN...ISOLATED SHOWERS/STORMS HAVE STARTED TO DEVELOP.
MAJORITY OF RAIN WILL MOVE OFF TO THE EAST BY MID MORNING.
HOWEVER...COLD FRONT WILL BRING SIGNIFICANTLY COLDER TEMPERATURES AT
850MB. SFC-850 TEMPERATURE DIFFERENCES WILL BE LARGE ENOUGH FOR SOME
LAKE EFFECT CLOUDS AND EVEN ISOLATED SHOWERS TO DEVELOP ALONG THE
COLD FRONT. WHILE MESOSCALE MODELS KEEP THE FORECAST DRY...HI-RES
MODELS INCLUDING THE HRRR SHOW THESE SHOWERS TO BEGIN BY EARLY
AFTERNOON. HAVE KEPT ISOLATED SHOWERS IN THE FORECAST THROUGH MOST
OF THE DAY TO ACCOUNT FOR THIS PRECIPITATION. WENT WITH LAMP
GUIDANCE FOR TEMPERATURES...WHICH YIELDS HIGHS ABOUT 10 DEGREES
BELOW NORMAL.
WHILE LAKE EFFECT CLOUD COVER WILL CONTINUE TONIGHT...THINK THAT
SHOWERS WILL NOT CONTINUE. BEHIND THE COLD FRONT...LOWS WILL BE
10-15 DEGREES COLDER THAN LAST NIGHT.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
EXPECT QUIET WEATHER THROUGH THIS STRETCH WITH HIGH PRESSURE ACROSS
THE GREAT LAKES. HAVE LOWERED TEMPERATURES A COUPLE DEGREES
WEDNESDAY AND WEDNESDAY NIGHT. THIS NOW KEEPS LOCATIONS NORTH OF
PITTSBURGH IN THE 60S FOR HIGHS...AND DROPS MANY LOCATIONS TO THE
40S WEDNESDAY NIGHT. TEMPERATURES THURS/THURS NIGHT WILL BE ABOUT 5
DEGREES HIGHER THAN THE PREVIOUS DAY.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
WHILE HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER FRIDAY AND
FRIDAY NIGHT...TROPICAL MOISTURE WILL START TO MOVE IN FROM THE
SOUTH. THIS WILL RESULT IN INCREASING CHANCES FOR SHOWERS AND
STORMS. MODERATING TEMPERATURES SHOULD BE NEAR NORMAL BY SATURDAY.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
CONDITIONS OVERNIGHT SHOULD DETERIORATE WITH SHOWERS AND LOW CLOUDS
MOVING THROUGH. EXPECT MVFR. COULD SEE A BRF PD OF IFR AT PORTS N
AND W OF PIT. CLD FNT PASSES 10-14Z. MVFR CIGS SHOULD LINGER THROUGH
MOST OF THE MORNING AND INTO EARLY AFTERNOON. IT IS LIKELY THAT
EASTERN AND NORTHERN PORTS WILL HOLD ON TO MVFR CLOUDS THE LONGEST.
CONDITIONS WILL IMPROVE TO VFR CU/STRATOCU...FROM WEST TO EAST..
DURING THE AFTN. EXP A WSHFT FM SW TO NW AFT FROPA WITH SOME SPEEDS
12G20KT TUE AFTN.
.OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/...
VFR CONDS EXPD THRU THE PD WITH BLDG HIGH PRES.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FLASH FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR MDZ001.
OH...NONE.
PA...NONE.
WV...FLASH FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR WVZ012-
021>023-041.
&&
$$