Alert archive / New York / Flash Flood Warnings in 2011

Flash Flood Warning 1, NWS Buffalo, NY

April 26, 2011Allegany County, New York

NWS Buffalo, NY issued this flash flood warning at Apr 26, 2011, 5:27 PM EDT for Allegany County, New York. It was in force for 5 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
Apr 26, 2011, 5:27 PM EDT (21:27 UTC)
Expired
Apr 26, 2011, 10:52 PM EDT
In force
5 hr
Issued by
NWS Buffalo, NY
Area
Storm-based polygon
Flood severity
None

County Allegany County, NY

The radar

The Buffalo radar (KBUF), 113 km from the middle of the area, began a volume at 21:30 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
Apr 26, 6:30 PM EDTFLASH FLOODWellsville, NYFLOODING 2-3 FEET OF WATER IN THE STREETS OF WELLSVILLE... NY.

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

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 9.5 hours before the alert went out and 110 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 2011-04-26Temperature 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 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 2011-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 128 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
493 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
128 m²/s²
0-3 km storm-relative helicity
237 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

934 
WGUS51 KBUF 262127
FFWBUF
NYC003-270130-
/O.NEW.KBUF.FF.W.0001.110426T2127Z-110427T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BUFFALO NY
527 PM EDT TUE APR 26 2011

THE NATIONAL WEATHER SERVICE IN BUFFALO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN ALLEGANY COUNTY IN WESTERN NEW YORK...
  THIS INCLUDES THE CITY OF WELLSVILLE...

* UNTIL 930 PM EDT

* AT 521 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  FLASH FLOODING FROM A THUNDERSTORM OVER THE WARNED AREA. ADDTIONAL 
  STORMS MAY MOVE INTO THE AREA THROUGH 630 PM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

ADDITIONAL RAINFALL AMOUNTS OF AN INCH ARE POSSIBLE IN THE WARNED 
AREA. WITH RECENT RAINFALL...ANY RAIN THAT DOES FALL WILL RUN OFF 
QUICKLY...AND MAY CAUSE WASHOUTS.

DO NOT DRIVE THROUGH FLOODED ROADWAYS...AS THE WATER MAY BE DEEPER 
THAN YOU THINK.

&&

LAT...LON 4200 7820 4220 7800 4236 7773 4225 7772
      4223 7774 4200 7774 4199 7802

$$

APFFEL
3 follow-up statements
769 
WGUS71 KBUF 262235
FFSBUF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
635 PM EDT TUE APR 26 2011

NYC003-270130-
/O.CON.KBUF.FF.W.0001.000000T0000Z-110427T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ALLEGANY NY-
635 PM EDT TUE APR 26 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 930 PM EDT FOR
SOUTHEASTERN ALLEGANY COUNTY...

AT 629 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
ANOTHER THUNDERSTORM CROSSING THE WARNED AREA. THIS STORM MAY BRING 
AN ADDITIONAL RAIN BETWEEN 630 PM AND 700 PM...WITH STORM TOTALS UP 
TO 3 INCHES.

SOME FLOODING HAS ALREADY OCCURRED IN AND NEAR WELLSVILLE. WITH 
ADDITIONAL RAINFALL...EXPECT CREEKS TO CONTINUE TO RISE RAPIDLY IN 
SPOTS. SOME ADDITIONAL FLOODING AND ROAD WASHOUTS ARE LIKELY IN 
EASTERN ALLEGANY COUNTY...INCLUDING THE CITY OF WELLSVILLE. CREEKS 
MAY CONTINUE TO RISE EVEN AFTER THE HEAVIEST RAIN HAS FALLEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED 
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 4200 7820 4220 7800 4236 7773 4225 7772
      4223 7774 4200 7774 4199 7802

$$

APFFEL
607 
WGUS51 KBUF 270057
FFWBUF
NYC003-270400-
/O.EXT.KBUF.FF.W.0001.000000T0000Z-110427T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BUFFALO NY
857 PM EDT TUE APR 26 2011

THE NATIONAL WEATHER SERVICE IN BUFFALO HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN ALLEGANY COUNTY IN WESTERN NEW YORK...
  THIS INCLUDES THE CITY OF WELLSVILLE...

* UNTIL MIDNIGHT EDT

* AT 849 PM EDT...NUMEROUS REPORTS OF FLOODING IN AND AROUND THE     
  CITY OF WELLSVILLE HAVE BEEN RECEIVED. WHILE THE MAJORITY OF THE   
  RAINFALL HAS ENDED...SOME OF THE SLOWER RESPONDING CREEKS MAY      
  CONTINUE TO RISE THROUGH THIS EVENING. FLOODING HAS ALSO DAMAGED   
  SOME AREA ROADS IN BOTH WELLSVILLE AND NEARBY RURAL LOCATIONS IN   
  ALLEGANY COUNTY. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

NEVER DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE 
ROADWAY. FLOOD WATERS ARE USUALLY DEEPER THAN THEY APPEAR. JUST ONE 
FOOT OF FLOWING WATER IS POWERFUL ENOUGH TO SWEEP VEHICLES OFF THE 
ROAD. WHEN ENCOUNTERING FLOODED ROADS MAKE THE SMART CHOICE...TURN 
AROUND...DONT DROWN.

LAT...LON 4200 7820 4220 7800 4236 7773 4225 7772
      4223 7774 4200 7774 4199 7802

$$

APFFEL
070 
WGUS71 KBUF 270252
FFSBUF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
1052 PM EDT TUE APR 26 2011

NYC003-270301-
/O.CAN.KBUF.FF.W.0001.000000T0000Z-110427T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ALLEGANY NY-
1052 PM EDT TUE APR 26 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHEASTERN
ALLEGANY COUNTY...

LAW ENFORCEMENT HAS INDICATED THAT THE FLOODING HAS 
RECEDED...THEREFORE THE FLOOD WARNING HAS BEEN CANCELLED.

LAT...LON 4200 7820 4220 7800 4236 7773 4225 7772
      4223 7774 4200 7774 4199 7802

$$

JJR

The office that day

Everything else NWS Buffalo, NY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 25, 8:36 PM EDTAreal Flood AdvisoryBUFChautauqua, Erie, Genesee6 hr
Apr 26, 3:07 AM EDTRiver Flood WarningBUFErie, Wyoming3 hr
Apr 26, 3:07 AM EDTRiver Flood WarningBUFErie3 hr
Apr 26, 3:41 AM EDTSmall Craft AdvisoryBUF18 hr
Apr 26, 12:59 PM EDTSpecial Weather StatementBUFAllegany31 min
Apr 26, 2:00 PM EDTSevere Thunderstorm WarningBUFOntario45 min
Apr 26, 2:26 PM EDTSevere Thunderstorm WarningBUFCayuga, Ontario, Oswego, Wayne49 min
Apr 26, 3:53 PM EDTSpecial Weather StatementBUFOswego52 min
Apr 26, 4:43 PM EDTSevere Thunderstorm WarningBUFGenesee, Monroe, Orleans47 min
Apr 26, 4:44 PM EDTSevere Thunderstorm WarningBUFMonroe46 min
Apr 26, 4:50 PM EDTSevere Thunderstorm WarningBUFCayuga, Oswego55 min
Apr 26, 4:53 PM EDTSpecial Marine WarningBUF58 min
Apr 26, 5:05 PM EDTSevere Thunderstorm WarningBUFLewis, Oswego40 min
Apr 26, 5:40 PM EDTSevere Thunderstorm WarningBUFCayuga, Ontario, Wayne50 min
Apr 26, 5:46 PM EDTSpecial Weather StatementBUFLewis59 min
Apr 26, 5:49 PM EDTSpecial Marine WarningBUF86 min
Apr 26, 6:14 PM EDTSpecial Weather StatementBUFAllegany61 min
Apr 26, 6:19 PM EDTAreal Flood AdvisoryBUFOntario, Wayne2 hr
Apr 26, 6:22 PM EDTSevere Thunderstorm WarningBUFAllegany38 min
Apr 26, 7:10 PM EDTFlash Flood WarningBUFOntario, Wayne3 hr

Nearby

Flash Flood Warnings in New York, 2011Every flash flood warning in 2011

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.