Alert archive / New York / Flash Flood Warnings in 2004

Flash Flood Warning 21, NWS Buffalo, NY

July 20, 2004Niagara County, New York

NWS Buffalo, NY issued this flash flood warning at Jul 20, 2004, 4:52 PM EDT for Niagara County, New York. It was in force for 113 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 20, 2004, 4:52 PM EDT (20:52 UTC)
Expired
Jul 20, 2004, 6:45 PM EDT
In force
113 min
Issued by
NWS Buffalo, NY
Area
Counties, with a storm outline in the text

County Niagara County, NY

The radar

The Buffalo radar (KBUF), 30 km from the middle of the area, began a volume at 20:52 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, 8.9 hours before the alert went out and 33 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 2004-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 145 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 12:00Z on 2004-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 112 square meters per square second.1939Sfc1 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
145 J/kg
Mixed-layer CIN
-47 J/kg
Mixed-layer LCL
1084 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
112 m²/s²
0-3 km storm-relative helicity
124 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 
WGUS51 KBUF 202052
FFWBUF
NYC063-202245-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BUFFALO NY
452 PM EDT TUE JUL 20 2004

THE NATIONAL WEATHER SERVICE IN BUFFALO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NIAGARA COUNTY IN WESTERN NEW YORK

* UNTIL 645 PM EDT

* AT 444 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM NEAR SANBORN...OR ABOUT 9 MILES
  NORTH OF NORTH TONAWANDA...MOVING EAST AT 10 MPH.

* THE THUNDERSTORM PRODUCING FLASH FLOODING WILL BE NEAR...
  NEWFANE AT 515 PM EDT...
  LOCKPORT AT 525 PM EDT...
  GASPORT AT 550 PM EDT...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE 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.


LAT...LON 4327 7899 4310 7897 4312 7857 4332 7852

$$

TJP
2 follow-up statements
000 
WGUS71 KBUF 202140
FFSBUF
NYC063-202245-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
540 PM EDT TUE JUL 20 2004

...A FLASH FLOOD WARNING CONTINUES UNTIL 645 PM EDT FOR NIAGARA
COUNTY...

AT 530 PM EDT...FLOODING FROM EARLIER STORMS WAS SUBSIDING...BUT 
WILL STILL BE A PROBLEM FOR AWHILE. 

THE THUNDERSTORM THAT PRODUCED THE FLASH FLOODING HAS WEAKENED AND 
MOVED SOUTH OUT OF THE COUNTY.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW
LYING AREAS ARE SUBJECT TO FLOODING.


LAT...LON 4327 7899 4310 7897 4312 7857 4332 7852

$$

APB
000 
WGUS71 KBUF 202240
FFSBUF
NYC063-202255-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
640 PM EDT TUE JUL 20 2004

...THE FLASH FLOOD WARNING FOR NIAGARA COUNTY IS EXPIRING AT 645 
PM...

AT 630 PM EDT RADAR SHOWED THE RAIN HAD EXITED NIAGARA COUNTY. 
FLOODING FROM EARLIER STORMS WAS SUBSIDING...BUT MAY STILL BE A 
PROBLEM FOR AWHILE. 


LAT...LON 4327 7899 4310 7897 4312 7857 4332 7852

$$

APB

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 12:42 PM EDTSevere Thunderstorm WarningBUFOrleans63 min
Jul 20, 1:30 PM EDTSpecial Marine WarningBUF2 hr
Jul 20, 2:37 PM EDTSevere Thunderstorm WarningBUFMonroe68 min
Jul 20, 2:49 PM EDTSevere Thunderstorm WarningBUFNiagara56 min
Jul 20, 4:30 PM EDTSevere Thunderstorm WarningBUFNiagara60 min

Nearby

Flash Flood Warnings in New York, 2004Every flash flood warning in 2004

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.