Flash Flood Warning 23, NWS State College, PA

CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
115 AM EDT MON JUL 31 2000

IT ALMOST SEEMS WORTH IT TO BRING UP MY DISCUSSION FROM LAST NIGHT
AND BLOCK COPY IT HERE...AS WEATHER HAS REMAINED VIRTUALLY
UNCHANGED. SCATTERED LOCALLY HEAVY CONVECTION SUNDAY WAS MORE ALONG
THE LINES OF WHAT I HAD EXPECTED FOR SATURDAY WHEN CLOUDS COVER PUT
A LID ON THINGS. HIGH DEWPOINTS AND SOME MARGINAL HEATING MANAGED TO
FUEL ACTIVITY TODAY WITH SOME ISOLATED REPORTS OF WIND DAMAGE... MUD
SLIDES AND FLOODING. DON'T SEE ANY REASON FOR SIG CHANGE TOMORROW AS
DEEP TROPICAL MOISTURE WILL STAY ENTRENCHED.

WEAK SHORTWAVES ROTATING UP ERN SIDE OF TROF TO OUR WEST SHUD ALLOW
THINGS TO LIGHT UP ONCE AGAIN LATER TODAY. WATER VAPOR IMAGERY SHOWS
MOISTURE CONTINUING TO FUNNEL FROM DEEP TROPICS NORTHWARD ALONG
EASTERN SEABOARD...WITH ANY NUMBER OF SMALL SHORTWAVES EMBEDDED IN
THE FLOW. MODEL OUTPUT INDICATES FLOW UP THRU AT LEAST 850 REMAINS
SE-SLY 15-20KT THRU LATE TODAY. PROGGED THETA-E RIDGE REMAINS IN
PLACE SO SEE NO CUT OFF OF FUEL FOR STORMS ANY TIME SOON. STILL NO
BUFKIT SOUNDING DATA AVAIL TONIGHT...SOMETHING FOR COMPUTER-HEADS TO
TAKE A LOOK AT TODAY. AWIPS SOUNDINGS CONTINUE TO SHOW DEEP MOISTURE
AND IMPRESSIVE INSTABILITY BY LATER TODAY. ALSO CONTINUES WITH THE
ODD LI OF -500+ THROWN IN FOR GOOD MEASURE. STILL MAINTAIN ITS AN
"AWIPS THING" AS ALGORITHM OBVIOUSLY AWRY WITH CALCULATIONS.
INTERESTING FEATURE TO NOTICE HOWEVER IS DECENT LOW LEVEL WIND
PROFILE FROM A SELY DIRECTION IN BOUNDARY LAYER TO A SWLY DIRECTION
FROM ABOUT 700-500MB. WINDS IN EXTREME LOW LEVELS ARE ON THE ORDER
OF 10-20KT BUT DON'T INCREASE MUCH WITH HGHT OR HELICITIES WUD BE
PRETTY IMPRESSIVE. MAIN THING THIS INDICATES IS CONTINUED ABILITY OF
STORMS TO TAP LOW LEVEL MOISTURE. STILL WAITING ON LATEST ENSEMBLE
DATA FROM MM5 AND IN HOUSE ETA MODEL RUNS...BUT LATEST DATA
CONTINUES TO SHOW ANOMALOUSLY HIGH LOW LEVEL MOISTURE POOLING OVER
THE REGION THRU LATER TODAY. THE 30/06Z MM5 RUN SHOWS 850 MOISTURE
ON THE ORDER OF 2-3 STANDARD DEVIATIONS ABOVE NORMAL BY THIS
EVENING...WHICH HAS PROVEN TO BE A GOOD INDICATOR OF HEAVY RAIN
POTENTIAL. WE MANAGED LOCAL FLOODING TODAY WITH STD DEVIATIONS ON
THE ORDER OF 1-2 ABOVE NORMAL. WITH PRECIPITABLE WATERS APPROACHING
2 INCHES AND PROGGED TO REMAIN HIGH...HAVE TO THINK LOCALIZED
FLOODING AGAIN A POSSIBILITY LATER TODAY AND THIS EVENING. STILL NO
REAL FEEL FOR WHERE THE BEST FOCUS WILL BE SO WILL HOLD OFF ON A
FLASH FLOOD WATCH...AND WILL ISSUE A POTENTIAL STATEMENT TO ADDRESS
OUR CONCERNS.

MED RANGE SHOWS SUMMER TO HAVE FINALLY ARRIVED AND EXPECTED TO STICK
AROUND AT LEAST THRU NEXT WEEKEND WHEN SLIGHTLY LOWER HGHTS FCST TO
DEVELOP OVER THE NERN US. IN THE MEANTIME WE GRADUALLY LOSE OUR
TROF...BUT STAY IN THE WEAKNESS BETWEEN THE BERMUDA RIDGE AND THE
MONSTER RIDGE THAT HAS BEEN BAKING THE WESTERN STATES FOR WHAT SEEMS
LIKE WEEKS NOW. AVN/MRF STILL TRY AND DEVELOP A TROPICAL SYSTEM FOR
GULF STATES LATER IN WEEK. SAT DOES SHOW AN AREA OF CLOUDS MOVING
INTO CTRL CARIBBEAN...BUT AT THIS TIME IT IS UNDER AN UPPER LOW AND
COLD POOL...NON TROPICAL LOOKING. HARD TO FOLLOW WHAT EXACTLY AVN IS
LATCHING ONTO WITH ITS DEVELOPMENT...BUT IT DEFINITELY HAS A WARM
CORE CYCLONE MOVING INTO GULF AT 72 HRS. SOMETHING TO WATCH I GUESS.

.CTP...ESF TO BE ISSUED TO ADDRESS HEAVY RAIN POTENTIAL.

LA CORTE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE STATE COLLEGE, PA
830 PM EDT SUN JUL 30 2000

TIME(EDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0445 PM    MARYSVILLE                PA   WIND DAMAGE
07/30/00   PERRY                          TREES DOWN.

0500 PM    MARYSVILLE                PA   FLOOD
07/30/00   PERRY                          WATER COVERED ROADWAYS IN
                                          MARYSVILLE.

0630 PM    5 SW CAMP HILL            PA   FLOOD
07/30/00   CUMBERLAND                     MINOR MUDSLIDES REPORTED
                                          IN HAMPDEN TOWNSHIP
                                          BETWEEN CAMP HILL AND
                                          MECHANICSBURG. NO
                                          PROPERTY DAMAGE
                                          REPORTED.

0700 PM    NANTY-GLO                 PA   WIND DAMAGE
07/30/00   CAMBRIA                        TREE DOWN ON PLANK ROAD

0705 PM    SALISBURY                 PA   FLOOD
07/30/00   SOMERSET                       ROUTE 219S BETWEEN BOYTON
                                          AND SALISBURY FLOODED IN
                                          NUMEROUS
                                          LOCATIONS. REPORTS OF
                                          SEVERAL ROAD WASHOUTS IN
                                          SALISBURY.

PAJ

PAZ012-017>019-024>028-033>037-041-042-045-046-049>053-056>059-
063>066-310900-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1020 PM EDT SUN JUL 30 2000

...THE THREAT OF FLOODING RAINS WILL GRADUALLY DECREASE LATE
TONIGHT...

SCATTERED THUNDERSTORMS WILL GRADUALLY DIMINISH IN INTENSITY ACROSS
CENTRAL PENNSYLVANIA LATE TONIGHT. HOWEVER...A FEW ISOLATED
THUNDERSTORMS MAY STILL BE CAPABLE OF CAUSING LOCALIZED FLOODING
UNTIL SHORTLY AFTER MIDNIGHT.

SCATTERED THUNDERSTORMS PRODUCED LOCALIZED FLOODING ACROSS CENTRAL
PENNSYLVANIA THIS EVENING. MUDSLIDES WERE REPORTED IN CUMBERLAND AND
COLUMBIA COUNTIES. BASEMENT FLOODING WAS REPORTED IN SOMERSET AND
COLUMBIA COUNTIES.

ISOLATED STORMS COULD STILL PRODUCE LOCALIZED 3 OR 4 INCH RAINFALL
AMOUNTS IN JUST A COUPLE OF HOURS UNTIL SHORTLY AFTER MIDNIGHT.
RAINFALL AMOUNTS OF OVER 3 INCHES IN A FEW HOURS CAN CAUSE FLOODING.
BE CAREFUL WHtEN TRAVELING THROUGH FLOOD PRONE AREAS AT NIGHT. NEVER
TRY TO CROSS WATER OF UNKNOWN DEPTH.

MSE