Alert archive / Pennsylvania / Flash Flood Warnings in 1999

Flash Flood Warning 70, NWS State College, PA

September 30, 1999Snyder County, Union County, Pennsylvania

NWS State College, PA issued this flash flood warning at Sep 30, 1999, 1:25 AM EDT for Snyder County, Union County, Pennsylvania. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Sep 30, 1999, 1:25 AM EDT (05:25 UTC)
Expired
Sep 30, 1999, 4:30 AM EDT
In force
3 hr
Issued by
NWS State College, PA
Area
Whole counties

Counties Snyder County, PA, Union County, PA

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 00:00Z, 5.4 hours before the alert went out and 176 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Phillips Aaf/Abe, MD at 00:00Z on 1999-09-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phillips Aaf/Abe, MD at 00:00Z on 1999-09-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1173 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
155 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KCTP 300533
FFWCTP
PAC109-119-300830-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
125 AM EDT THU SEP 30 1999

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SNYDER COUNTY.
  UNION COUNTY.

* UNTIL 430 AM EDT.

* AT 125 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  A LARGE AREA OF MODERATE TO HEAVY RAINFALL OCCURRING ACROSS UNION  
  AND SNYDER COUNTIES. RAINFALL SINCE THE EVENING HOURS OF WEDNESDAY 
  TOTALED BETWEEN 2.5 AND 3 INCHES ACROSS THE WARNED AREA.           
  ADDITIONAL RAINFALL OF AROUND 1 INCH WILL OCCUR OVER THE NEXT 
  3 HOURS.

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING OF 
SMALL CREEKS AND STREAMS...ALONG WITH SIGNIFICANT PONDING OF WATER 
IN POOR DRAINAGE AREAS ON HIGHWAYS...STREETS AND UNDERPASSES.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE 
DANGERS OF FLOODS AND FLA&SH FLOODS. DO NOT DRIVE YOUR VEHICLE INTO 
AREAS WHERE THE WATER COVERS THE ROADWAY. VEHICLES CAUGHT IN RISING 
WATER SHOULD BE ABANDONED. MOVE TO HIGHER GROUND.

.END/ LAMBERT

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS State College, PA wrote its last area forecast discussion before this flash flood warning went out at Sep 29, 9:30 PM EDT, 3 hours 55 minutes earlier.

Area forecast discussion, Sep 29, 9:30 PM EDT, 3 hours 55 minutes before
CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
930 PM EDT WED SEP 29 1999

COLD FRONT MOVING A BIT FASTER THAN PREVIOUSLY THOUGHT...JUST ABOUT
TO ENTER THE WESTERN AREAS OF CTP CWA.

TWO THINGS TO CONSIDER. FIRST IS HIGH WIND WARNING. WITH VAD WINDS
PRETTY MUCH CONFIRMING WHAT THE MODELS WERE PROJECTING...THAT IS A
50 KT WIND AT AROUND 5K FEET...THINK I WILL KEEP HIGH WIND WARNING.
GOOD BAND OF CONVECTION AHEAD OF THE FRONT MAY MIX DAMAGING WINDS
DOWN TO THE SURFACE. ALTHOUGH SEVERE THREAT DIMINISHED...NEED TO
KEEP SOME TYPE OF WARNING OUT FOR THE HIGH WINDS.

AS FOR THE FLOODING...HAVE NOT SEEN ANY YET. IF FRONT CONTINUES TO
MOVE AT A GOOD CLIP...PROBABLY WILL SEE LITTLE IN THE WAY OF
FLOODING. HOWEVER STILL EXPECTING PCPN TO BLOSSOM SOMEWHAT OVER
CENTRAL AND EASTERN ZONES...WITH ADDED LL CONVERGENCE OF STRONG WEST
WIND BEHIND FRONT AND SOUTHEAST OVER SUSQUEHANNA VALLEY. ALSO...GULF
AND ATLANTIC MOISTURE WILL CONTINUE TO BE INCREASINGLY TAPPED WITH
TIME OVERNIGHT. HATE TO MAKE ADJUSTMENTS JUST AS HEAVIEST RAIN
MOVING INTO THE CWA. WILL THEREFORE KEEP THE WATCH INTACT AS WELL.

OVERALL...SEE NO MAJOR CHANGES TO THE OVERNIGHT ZONES...AS FORECAST
PACKAGE WAS PRETTY MUCH TAILORED A FEW HOURS AGO WITH THE PREVIOUS
UPDATE. WILL ADJUST TIMING OF WSHFT AND FROPA AS NEEDED.

.CTP...FLASH FLOOD WATCH INTO THU AM ALL COUNTIES.
    ...HIGH WIND WATCH OVERNIGHT ALL COUNTIES.

JUNG

In the hours before

Special weather statement, Sep 29, 8:10 PM EDT, 5 hours 15 minutes before
PAZ004>006-010>012-017>019-024>026-033>035-045-300200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
810 PM EDT WED SEP 29 1999

...THE TORNADO WATCH FOR CENTRAL PENNSYLVANIA HAS BEEN CANCELLED...

THE NATIONAL WEATHER SERVICE HAS CANCELLED THE TORNADO WATCH FOR THE
FOLLOWING COUNTIES IN CENTRAL PENNSYLVANIA...

WARREN... MCKEAN... POTTER... ELK... CAMERON... CLINTON... CENTRE...
CLEARFIELD... CAMBRIA... BLAIR... HUNTINGDON... SOMERSET... BEDFORD
AND FULTON.

SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE REGION OVERNIGHT.
ALTHOUGH ANY INDIVIDUAL THUNDERSTORM MAY PRODUCE A LOCAL GUST OF
DAMAGING WIND...THE THREAT OF TORNADOES IS NO LONGER PRESENT.

A HIGH WIND WARNING REMAINS IN EFFECT FOR ALL OF CENTRAL
PENNSYLVANIA OVERNIGHT.

STAY TUNED TO NOAA WEATHER RADIO...THE OFFICIAL VOICE OF THE
NATIONAL WEATHER SERVICE...OR YOUR FAVORITE TELEVISION OR COMMERCIAL
RADIO NEWS SOURCE FOR LATER STATEMENTS AND FORECASTS.

.END/ JUNG

ADDITIONAL WEATHER INFORMATION CAN BE FOUND ON THE WORLD WIDE WEB AT:

HTTP://BOOKEND.MET.PSU.EDU (ALL LOWER CASE)
Special weather statement, Sep 29, 8:10 PM EDT, 5 hours 15 minutes before
PAZ004>006-010>012-017>019-024>026-033>035-045-300200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
810 PM EDT WED SEP 29 1999

...THE TORNADO WATCH FOR CENTRAL PENNSYLVANIA HAS BEEN CANCELLED...

THE NATIONAL WEATHER SERVICE HAS CANCELLED THE TORNADO WATCH FOR THE
FOLLOWING COUNTIES IN CENTRAL PENNSYLVANIA...

WARREN... MCKEAN... POTTER... ELK... CAMERON... CLINTON... CENTRE...
CLEARFIELD... CAMBRIA... BLAIR... HUNTINGDON... SOMERSET... BEDFORD
AND FULTON.

SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE REGION OVERNIGHT.
ALTHOUGH ANY INDIVIDUAL THUNDERSTORM MAY PRODUCE A LOCAL GUST OF
DAMAGING WIND...THE THREAT OF TORNADOES IS NO LONGER PRESENT.

A HIGH WIND WARNING REMAINS IN EFFECT FOR ALL OF CENTRAL
PENNSYLVANIA OVERNIGHT.

STAY TUNED TO NOAA WEATHER RADIO...THE OFFICIAL VOICE OF THE
NATIONAL WEATHER SERVICE...OR YOUR FAVORITE TELEVISION OR COMMERCIAL
RADIO NEWS SOURCE FOR LATER STATEMENTS AND FORECASTS.

.END/ JUNG

ADDITIONAL WEATHER INFORMATION CAN BE FOUND ON THE WORLD WIDE WEB AT:

HTTP://BOOKEND.MET.PSU.EDU (ALL LOWER CASE)

The office that day

Everything else NWS State College, PA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 29, 10:06 PM EDTSevere Thunderstorm WarningCTPBlair, Cambria, Centre, Clearfield54 min
Sep 29, 10:06 PM EDTSevere Thunderstorm WarningCTPCameron54 min
Sep 29, 10:27 PM EDTSevere Thunderstorm WarningCTPClinton, Potter78 min
Sep 29, 11:43 PM EDTSevere Thunderstorm WarningCTPClinton47 min
Sep 29, 11:46 PM EDTSevere Thunderstorm WarningCTPClinton44 min
Sep 30, 12:09 AM EDTSevere Thunderstorm WarningCTPJuniata, Snyder51 min
Sep 30, 12:09 AM EDTSevere Thunderstorm WarningCTPJuniata, Snyder66 min
Sep 30, 12:35 AM EDTSevere Thunderstorm WarningCTPCumberland, Dauphin40 min
Sep 30, 1:01 AM EDTSevere Thunderstorm WarningCTPColumbia, Lycoming, Sullivan59 min
Sep 30, 1:01 AM EDTSevere Thunderstorm WarningCTPMontour, Northumberland59 min
Sep 30, 1:02 AM EDTSevere Thunderstorm WarningCTPLebanon, Schuylkill43 min

Nearby

Flash Flood Warnings in Pennsylvania, 1999Every flash flood warning in 1999

Sources

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.