Alert archive / Pennsylvania / Flash Flood Warnings in 1990

Flash Flood Warning 12, NWS State College, PA

October 13, 1990Adams County, Pennsylvania

NWS State College, PA issued this flash flood warning at Oct 13, 1990, 9:44 AM EDT for Adams County, Pennsylvania. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Oct 13, 1990, 9:44 AM EDT (13:44 UTC)
Expired
Oct 13, 1990, 12:45 PM EDT
In force
3 hr
Issued by
NWS State College, PA
Area
Whole counties

County Adams County, PA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 1.7 hours before the alert went out and 104 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, Washington/Dulle, VA at 12:00Z on 1990-10-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 372 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 1990-10-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 68 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
372 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
602 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
68 m²/s²
0-3 km storm-relative helicity
120 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.8

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KHAR 131344 RRA
FFWHAR
PAC001-131645-
 
BULLETIN - EBS ACTIVATION REQUESTED
SMALL STREAM AND URBAN FLOOD WARNING
NATIONAL WEATHER SERVICE HARRISBURG PA
944 AM EDT SAT OCT 13 1990
 
THE NATIONAL WEATHER SERVICE IN HARRISBURG HAS ISSUED A
SMALL STREAM AND URBAN FLOOD WARNING EFFECTIVE UNTIL 1245 PM EDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN SOUTH CENTRAL PENNSYLVANIA
          ...ADAMS
 
ADAMS COUNTY CONTROL REPORTED CONDWAGO CREEK...TOMS CREEK AND MARSH
CREEK OUT OF THEIR BANKS. AT 940 AM RADAR SHOWED RAIN AND SHOWERS
FALLING OVER MOSY OF ADAMS COUNTY ALTHOUGH THE HEAVY RAIN HAS MOVED
TO THE EAST INTO YORK COUNTY.
 
 
 
 
DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY.  T!HE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO
CROSS SAFELY.  VEHICLES CAUGHT IN RISING WATER SHOULD BE
ABANDONED QUICKLY.  MOVE TO HIGHER GROUND.

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.

In the hours before

Special weather statement, Oct 13, 9:19 AM EDT, 25 minutes before
PAZ009-131430-
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HARRISBURG PA.
910 AM EDT    SAT  OCT 13 1990

...SMALL STREAM FLOOD WATCH REMAINS IN EFFECT FOR ALL THE SUSQUEHANNA
    VALLEY...
...THUNDERSTORMS WITH HEAVY RAIN MOVING THROUGH THE EASTERN PORTIONS OF
   THE LOWER SUSQUEHANNA VALLEY...

AT 905 AM RADAR SHOWED A BROKEN BAND OF THUNDERSTORMS REACHING FROM
NORTHERN DAUPHIN COUNTY...SOUTH TO JUST EAST OF HARRISBURG AND ON SOUTH
TO NEAR HANOVER IN YORK COUNTY. RAIN AND SCATTERED SHOWERS COVERED MOST
OF THE REMAINDER OF THE SUSQUEHANNA VALLEY.

THE THUNDERSTORMS WERE MOVING NORTH AROUND 15 MILES AN HOUR AND THE RAIN
AND SHOWERS WERE MOVING NORTH NORTHEAST AROUND 20 TO 25 MILES AN HOUR.

WSO HAR JORDAN

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 13, 1:49 AM EDTFlash Flood WarningCTPNorthumberland, Perry56 min
Oct 13, 2:25 AM EDTFlash Flood WarningCTPCumberland, Perry65 min
Oct 13, 2:25 AM EDTFlash Flood WarningCTPNorthumberland, Union65 min
Oct 13, 3:44 AM EDTFlash Flood WarningCTPNorthumberland, Snyder, Union61 min
Oct 13, 3:44 AM EDTFlash Flood WarningCTPCumberland, Juniata, Perry61 min
Oct 13, 4:50 AM EDTFlash Flood WarningCTPNorthumberland, Perry, Snyder, Union55 min
Oct 13, 5:42 AM EDTFlash Flood WarningCTPNorthumberland, Perry, Snyder, Union2 hr
Oct 13, 6:50 AM EDTFlash Flood WarningCTPBradford4 hr
Oct 13, 7:55 AM EDTFlash Flood WarningCTPLycoming4 hr
Oct 13, 9:50 AM EDTFlash Flood WarningCTPLycoming4 hr
Oct 13, 10:28 AM EDTFlash Flood WarningCTPUnion3 hr
Oct 13, 3:49 PM EDTFlash Flood WarningCTPCumberland4 hr

Nearby

Flash Flood Warnings in Pennsylvania, 1990Every flash flood warning in 1990

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.