Alert archive / Pennsylvania / Flash Flood Warnings in 2014

Flash Flood Warning 13, NWS Pittsburgh, PA

August 21, 2014Jefferson County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Aug 21, 2014, 5:12 PM EDT for Jefferson County, Pennsylvania. It was in force for 3 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 21, 2014, 5:12 PM EDT (21:12 UTC)
Expired
Aug 21, 2014, 8:15 PM EDT
In force
3 hr
Issued by
NWS Pittsburgh, PA
Area
Storm-based polygon
Flood severity
None

County Jefferson County, PA

The radar

The State College radar (KCCX), 74 km from the middle of the area, began a volume at 21:15 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.

What was reported inside it

TimeReportWhereRemark
Aug 21, 5:14 PM EDTFLASH FLOOD2 S Sykesville, PAROUTE 119 CLOSED DUE TO FLOODING IN MULTIPLE LOCATIONS.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Pittsburgh, PA (KAGC), launched 12:00Z, 9.2 hours before the alert went out and 119 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, Pittsburgh, PA at 12:00Z on 2014-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 324 joules per kilogram.LCLLFCEL10008507005003002001001 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, Pittsburgh, PA at 12:00Z on 2014-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 24 square meters per square second.19395878Sfc1 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
324 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
1058 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
100 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

456 
WGUS51 KPBZ 212112
FFWPBZ
PAC065-220015-
/O.NEW.KPBZ.FF.W.0013.140821T2112Z-140822T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
512 PM EDT THU AUG 21 2014

THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN JEFFERSON COUNTY IN WEST CENTRAL PENNSYLVANIA...

* UNTIL 815 PM EDT

* AT 505 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  VERY HEAVY RAIN CAPABLE OF PRODUCING FLASH FLOODING OVER SOUTHEAST
  JEFFERSON COUNTY.

* THE HEAVY RAIN WILL AFFECT MAINLY RURAL AREAS OF THE INDICATED
  COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PLEASE REPORT HIGH WATER BY CALLING...412-262-1988...POSTING TO THE
NWS PITTSBURGH FACEBOOK PAGE...OR USING TWITTER @NWSPITTSBURGH.

&&

LAT...LON 4091 7890 4091 7891 4110 7910 4106 7880
      4091 7880 4090 7880

$$
1 follow-up statement
437 
WGUS71 KPBZ 212211
FFSPBZ

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH PA
611 PM EDT THU AUG 21 2014

PAC065-220015-
/O.CON.KPBZ.FF.W.0013.000000T0000Z-140822T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
JEFFERSON PA-
611 PM EDT THU AUG 21 2014

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM EDT FOR
JEFFERSON COUNTY IN WEST CENTRAL PENNSYLVANIA...

NATIONAL WEATHER SERVICE DOPPLER RADAR SHOWED THAT THE HEAVY RAIN 
HAS MOVED OUT OF SOUTHERN JEFFERSON COUNTY. RUNOFF FROM THE 
THUNDERSTORMS...HOWEVER...WILL CONTINUE TO CAUSE FLOODING. RADAR 
ESTIMATES THAT UP TO 2.50 INCHES OF RAIN FELL DURING THE LATE 
AFTERNOON.

JEFFERSON COUNTY EMERGENCY MANAGEMENT REPORTS THAT ROUTE 119 IS 
CLOSED IN HENDERSON TOWNSHIP DUE TO FLOODING.  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

NEVER ATTEMPT TO DRIVE THROUGH FLOODED ROADWAYS. 

PLEASE REPORT HIGH WATER BY CALLING...412-262-1988...POSTING TO THE
NWS PITTSBURGH FACEBOOK PAGE...OR USING TWITTER @NWSPITTSBURGH.

&&

LAT...LON 4091 7890 4091 7891 4110 7910 4106 7880
      4091 7880 4090 7880

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 8:13 PM EDTSpecial Weather StatementPBZForest47 min
Aug 20, 8:34 PM EDTSpecial Weather StatementPBZFayette41 min
Aug 20, 8:39 PM EDTSevere Thunderstorm WarningPBZFayette, Greene, Washington51 min
Aug 20, 9:04 PM EDTSpecial Weather StatementPBZJefferson41 min
Aug 20, 9:51 PM EDTAreal Flood AdvisoryPBZJefferson3 hr
Aug 21, 2:24 PM EDTSpecial Weather StatementPBZMercer36 min
Aug 21, 3:09 PM EDTSpecial Weather StatementPBZJefferson51 min
Aug 21, 3:50 PM EDTFlash Flood WarningPBZJefferson5 hr
Aug 21, 3:53 PM EDTFlash Flood WarningPBZMercer5 hr
Aug 21, 4:16 PM EDTTornado WarningPBZJefferson29 min

Nearby

Flash Flood Warnings in Pennsylvania, 2014Every flash flood warning in 2014

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.