Alert archive / New York / Flash Flood Warnings in 2009

Flash Flood Warning 11, NWS Buffalo, NY

August 5, 2009Erie County, New York

NWS Buffalo, NY issued this flash flood warning at Aug 5, 2009, 12:33 AM EDT for Erie County, New York. It was in force for 2 hr. 4 reports 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 5, 2009, 12:33 AM EDT (04:33 UTC)
Expired
Aug 5, 2009, 2:40 AM EDT
In force
2 hr
Issued by
NWS Buffalo, NY
Area
Storm-based polygon
Flood severity
None

County Erie County, NY

The radar

The Buffalo radar (KBUF), 37 km from the middle of the area, began a volume at 04:36 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 5, 12:55 AM EDTFLASH FLOODBoston, NYBACK CREEK ROAD WASHED OUT. WILL BE CLOSED 5-7 DAYS.
Aug 5, 1:30 AM EDTFLASH FLOODEden, NYWIDESPREAD FLOODING OF ROADS AND BASEMENTS.
Aug 5, 1:58 AM EDTFLASH FLOODEden, NYSCHNITZIUS ROAD WASHED OUT. WILL BE CLOSED 5-7 DAYS.
Aug 5, 2:00 AM EDTFLASH FLOODEvans Center, NYWIDESPREAD FLOODING OF ROADS AND BASEMENTS.

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 00:00Z, 4.6 hours before the alert went out and 37 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 00:00Z on 2009-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1480 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, Buffalo Intl Airport, NY at 00:00Z on 2009-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 104 square meters per square second.1939587897Sfc1 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
1480 J/kg
Mixed-layer CIN
-15 J/kg
Mixed-layer LCL
735 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
104 m²/s²
0-3 km storm-relative helicity
202 m²/s²
Significant tornado parameter
0.9
Supercell composite
4.8

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KBUF 050433
FFWBUF
NYC029-050730-
/O.NEW.KBUF.FF.W.0011.090805T0433Z-090805T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BUFFALO NY
1233 AM EDT WED AUG 5 2009

THE NATIONAL WEATHER SERVICE IN BUFFALO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHERN ERIE COUNTY IN WESTERN NEW YORK...
  THIS INCLUDES THE CITIES OF EDEN...DERBY...NORTH COLLINS AND ANGOLA...

* UNTIL 330 AM EDT

* AT 1227 AM EDT...VERY HEAVY RAINS FROM SLOW MOVING THUNDERSTORMS   
  CONTINUE OVER EVANS...COLLINS AND DERBY. RADAR INDICATES THAT OVER 
  TWO INCHES OF RAIN HAS FALLEN IN JUST OVER AN HOUR. THE RAIN       
  SHOULD TAPER OFF AFTER 1 AM...BUT FLOODING OF STREAMS AND CREEKS   
  SUCH AS EIGHTEENMILE CREEK MAY OCCUR DUE TO RAPID RUNOFF. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL 
CREEKS AND STREAMS...SUCH AS EIGHTEENMILE CREEK...AS WELL AS 
FARMLAND ALONG THE BANKS OF CREEKS AND STREAMS. FLOODING AT NIGHT IS 
ALWAYS DANGEROUS...ESPECIALLY IN RURAL HILLY AREAS.

&&

LAT...LON 4263 7911 4267 7907 4270 7906 4274 7896
      4276 7864 4256 7873 4260 7913

$$

SFM
2 follow-up statements
000 
WGUS71 KBUF 050532
FFSBUF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
132 AM EDT WED AUG 5 2009

NYC029-050730-
/O.CON.KBUF.FF.W.0011.000000T0000Z-090805T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ERIE NY-
132 AM EDT WED AUG 5 2009

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 AM EDT FOR
SOUTHERN ERIE COUNTY...

AT 129 AM EDT...THE SHOWERS AND THUNDERSTORMS WHICH DROPPED OVER TWO 
INCHES OF RAIN IN AN HOUR FROM MIDNIGHT TO 1 AM HAVE MOVED SOUTH AND 
EAST OF THE AREA. THERE HAVE BEEN REPORTS OF FLOODING THOUGH...AND 
EXCESSIVE RUNOFF WILL CONTINUE FOR AWHILE LONGER...ESPECIALLY AS 
MUCH OF THIS AREA HAS VERY HILLY TERRAIN...SO THE WARNING WILL 
CONTINUE.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
DERBY...BOSTON...EVANS AND EDEN.

LAT...LON 4263 7911 4267 7907 4270 7906 4274 7896
      4276 7864 4256 7873 4260 7913

$$

SFM
000 
WGUS71 KBUF 050640
FFSBUF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
240 AM EDT WED AUG 5 2009

NYC029-050649-
/O.CAN.KBUF.FF.W.0011.000000T0000Z-090805T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ERIE NY-
240 AM EDT WED AUG 5 2009

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHERN ERIE
COUNTY...

RUNOFF FROM THE TWO TO THREE INCHES OF RAIN THAT FELL IN 
THUNDERSTORMS BETWEEN MIDNIGHT AND 130 AM HAS RECEDED. NO FURTHER 
FLOODING IS EXPECTED...THUS THE FLOOD WARNING HAS BEEN CANCELLED.

LAT...LON 4263 7911 4267 7907 4270 7906 4274 7896
      4276 7864 4256 7873 4260 7913

$$

SFM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 11:10 PM EDTSpecial Marine WarningBUF65 min
Aug 5, 12:11 AM EDTAreal Flood AdvisoryBUFErie3 hr
Aug 5, 9:34 AM EDTSmall Craft AdvisoryBUF12 hr

Nearby

Flash Flood Warnings in New York, 2009Every flash flood warning in 2009

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.