Flash Flood Warning 22, NWS State College, PA

Issued

Sep 11, 1997, 12:57 AM EDT (04:57 UTC)

Expired

Sep 11, 1997, 4:55 AM EDT

In force

4 hr

Issued by

NWS State College, PA

Area

Whole counties

Counties Snyder County, PA, Union County, PA

000 
TTAA00 KCTP 110458
FFWCTP
PAC067-109-119-110855-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1257 AM EDT THU SEP 11 1997

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL 455 AM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...

IN SOUTH CENTRAL PENNSYLVANIA

   ...JUNIATA COUNTY

IN CENTRAL PENNSYLVANIA

   ...UNION COUNTY
   ...SNYDER COUNTY
 
AT 1250 AM EDT... DOPPLER RADAR FROM STATE COLLEGE SHOWED A BAND OF
VERY HEAVY RAIN EXTENDING FROM WESTERN UNION COUNTY SOUTHWEST
ACROSS WESTERN SNYDER COUNTY AND INTO CENTRAL JUNIATA COUNTY.
DOPPLER RADAR RAINFALL ESTIMATES SHOWED BETWEEN ONE AND THREE
INCHES OF RAIN SINCE LAST EVENING ACROSS CENTRAL JUNIATA COUNTY
AND FAR SOUTHERN SNYDER COUNTY. THE HEAVIEST RAIN SO FAR WAS NEAR
PORT ROYAL AND MIFFLINTOWN IN JUNIATA COUNTY.

THE BAND OF HEAVY RAINFALL WAS DRIFTING SLOWLY EAST AND WILL
CONTINUE TO PELT MUCH OF NORTHERN JUNIATA COUNTY AND MANY LOCATIONS
IN SNYDER AND UNION COUNTIES EARLY THIS MORNING. RUNOFF FROM THE
RECENT HEAVY RAINFALL AND ADDITIONAL HEAVY RAINFALL OVERNIGHT WILL
LIKELY CAUSE FLOODING OF STREAMS... CREEKS AS WELL AS URBAN
AND POOR DRAINAGE AREAS.
 
BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE
THE DANGERS OF FLASH FLOODING.

IF FLASH FLOODING IS OBSERVED...ACT QUICKLY.  MOVE TO ESCAPE FLOOD
WATERS.  DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS
RISING.

NICOSIA

NWS State College, PA wrote its last area forecast discussion before this flash flood warning went out at Sep 10, 9:18 PM EDT, 3 hours 39 minutes earlier.

CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
915 PM EDT WED SEP 10 1997

...SUGGESTIONS...

.PIT/PHL...FCST ON TRACK. WILL NEED TO WATCH ACTIVITY MOVING
NORTHWARD OVER CENTRAL VA. PER CORD WITH PHL/PIT HAVE REQ THAT THE
FOLLOWING COUNTIES BE PUT IN A FLASH FLOOD WATCH FOR TONIGHT:
26,27,28,35,36,56,57,59,63>66. REPORTS FROM YORK...ADAMS AND
FRANKLIN COUNTIES INDICATE ANYWHERE FROM 1-3 INCHES OF RAIN HAS
FALLEN IN THE LAST SEVERAL HRS. ADDITIONAL RAINS MOVING IN MAY
CAUSE PROBLEMS.

...DISCUSSION...

THE NGM HAS AGAIN OUT-PERFORMED THE OTHER MODELS WITH THIS SYS.

AT 00Z SFC LOW WAS OVER LK ERI AND UPPER LOW OVER W OH. COLD FRONT
WHICH IS NOW BECOMING OCCLUDED IS MOVING INTO W PA ATTM. WRM FRONT
EXTENDS SOUTH TO BLF-LYH-IAD-MIV.

OF SOME CONCERN IS SHRTWV SLIDING N ACROSS VA ALONG N-S WRM FRONT.
WATCHING KLWX LOOP AS LONG NARROW LINE OF HVY PRECIP ETENDS FROM S-
CENTRAL PA INTO S VA. IR PICTURE FROM RAMSDIS SHOWS CLD TOPS
WARMING AND AS ACTIVITY CONTINUES N EXPECT A WEAKENING TREND.
BUT...WITH WARM FRONT SLIDING N INTO S PA WILL LIKELY KEEP ACTIVITY
TRAINING OVER SAME AREA OVERNIGHT.

NGM HAS A GOOD HANDLE ON THIS SHRTWV AS IT SLIDES INTO FCST/A ARND
06Z. NOTICED THE NGM WENT BONKERS WITH FCST LI'S ON THU. THIS IS
PARTLY DUE TO THE COLDER 5H FCST TEMPS (-17C) AND THE EXPECTATION
OF WARM SFC TEMPS. THE ETA LOOKS MORE REASONABLE.

WINTHER

Flash Flood Warnings in Pennsylvania, 1997Every flash flood warning in 1997

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.