Alert archive / Pennsylvania / Flash Flood Warnings in 1999

Flash Flood Warning 21, NWS State College, PA

January 24, 1999Union County, Pennsylvania

NWS State College, PA issued this flash flood warning at Jan 24, 1999, 8:00 AM EST for Union County, Pennsylvania. It was in force for 4 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
Jan 24, 1999, 8:00 AM EST (13:00 UTC)
Expired
Jan 24, 1999, 12:00 PM EST
In force
4 hr
Issued by
NWS State College, PA
Area
Whole counties

County Union County, PA

The radar

The State College radar (KCCX), 79 km from the middle of the area, began a volume at 13:02 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 1.0 hours before the alert went out and 257 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, Buffalo Intl Airport, NY at 12:00Z on 1999-01-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Buffalo Intl Airport, NY at 12:00Z on 1999-01-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -144 square meters per square second.1939587897117136Sfc1 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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
490 m above ground
0-6 km bulk shear
76 kt
0-1 km storm-relative helicity
-144 m²/s²
0-3 km storm-relative helicity
-121 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 241301
FFWCTP
PAC037-097-119-241700-

BULLETIN - EAS ACTIVATION REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
800 AM EST SUN JAN 24 1999

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* FLOOD WARNING FOR...
  UNION COUNTY IN CENTRAL PENNSYLVANIA.
  NORTHUMBERLAND COUNTY IN CENTRAL PENNSYLVANIA.
  COLUMBIA COUNTY IN CENTRAL PENNSYLVANIA.

* UNTIL 1200 PM EST.

* AT 8 AM...RAIN WAS ENDING ACROSS CENTRAL AND EASTERN PENNSYLVANIA.

* RUNOFF FROM EARLIER RAIN AND SNOWMELT HAS CAUSED FLOODING OF SOME
  STREAMS AND POOR DRAINAGE AREAS. IN NORTHUMBERLAND COUNTY...
  HAMILTON AND REGAN STREET UNDERPASSES ARE CLOSED IN THE TOWN OF
  SUNBURY. ELSEWHERE IN THE WARNING AREA...NUMEROUS SECONDARY ROADS
  HAVE BEEN FLOODED.

USE CAUTION WHILE TRAVELING TODAY...AS SOME ROADS AND LOW-LYING
AREAS MAY BE COVERED BY FLOODWATERS.

.END/KF

&

The office that day

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

IssuedProductOfficeCountiesLasted
Jan 23, 7:32 PM ESTFlash Flood WarningCTPHuntingdon6 hr
Jan 23, 10:40 PM ESTFlash Flood WarningCTPCentre6 hr
Jan 23, 11:01 PM ESTFlash Flood WarningCTPJuniata, Mifflin6 hr
Jan 24, 1:58 AM ESTFlash Flood WarningCTPHuntingdon3 hr
Jan 24, 3:58 AM ESTFlash Flood WarningCTPNorthumberland, Union4 hr
Jan 24, 4:39 AM ESTFlash Flood WarningCTPCentre, Huntingdon, Juniata, Mifflin3 hr
Jan 24, 7:51 AM ESTFlash Flood WarningCTPCentre4 hr
Jan 24, 7:51 AM ESTFlash Flood WarningCTPJuniata4 hr
Jan 24, 8:00 AM ESTFlash Flood WarningCTPColumbia, Northumberland4 hr
Jan 24, 9:23 AM ESTFlash Flood WarningCTPHuntingdon3 hr
Jan 24, 11:59 AM ESTFlash Flood WarningCTPHuntingdon4 hr
Jan 24, 11:59 AM ESTFlash Flood WarningCTPColumbia4 hr
Jan 24, 11:59 AM ESTFlash Flood WarningCTPUnion4 hr
Jan 24, 1:16 PM ESTFlash Flood WarningCTPLycoming3 hr

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; radar from the NEXRAD Level II archive.