Alert archive / New York / Flash Flood Warnings in 2021

Flash Flood Warning 23, NWS Buffalo, NY

September 13, 2021Erie County, Genesee County, Wyoming County, New York

NWS Buffalo, NY issued this flash flood warning at Sep 13, 2021, 12:25 AM EDT for Erie County, Genesee County, Wyoming County, New York. 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
Sep 13, 2021, 12:25 AM EDT (04:25 UTC)
Expired
Sep 13, 2021, 3:15 AM EDT
In force
3 hr
Issued by
NWS Buffalo, NY
Area
Storm-based polygon
Flood severity
None

Counties Erie County, NY, Genesee County, NY, Wyoming County, NY

The radar

The Buffalo radar (KBUF), 18 km from the middle of the area, began a volume at 04:30 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
Sep 13, 12:30 AM EDTFLASH FLOOD2 N Buffalo, NYWATER FLOWING OVER SEVERAL ROADS NEAR DELAWARE PARK, UP TO THE BOTTOM OF CAR DOORS IN SOME LOCATIONS.

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, 4.4 hours before the alert went out and 19 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 2021-09-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 412 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 2021-09-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 205 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
412 J/kg
Mixed-layer CIN
-125 J/kg
Mixed-layer LCL
706 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
205 m²/s²
0-3 km storm-relative helicity
168 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.5

Open this sounding in Storm Lab

The text

As transmitted.

103 
WGUS51 KBUF 130425
FFWBUF
NYC029-037-121-130830-
/O.NEW.KBUF.FF.W.0023.210913T0425Z-210913T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Buffalo NY
1225 AM EDT Mon Sep 13 2021

The National Weather Service in Buffalo has issued a

* Flash Flood Warning for...
  Erie County in western New York...
  Southwestern Genesee County in western New York...
  Northwestern Wyoming County in western New York...

* Until 430 AM EDT.

* At 1225 AM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Additional rainfall amounts of 0.5 to 1 inch are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Buffalo, Cheektowaga, West Seneca, North Tonawanda, Clarence, 
  Lackawanna, Kenmore, Depew, Amherst, Tonawanda, Lancaster, 
  Hamburg, East Aurora, Williamsville, Darien Lakes State Park, 
  Grand Island, Evans, Elma, Boston and Eden.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4258 7919 4272 7909 4276 7899 4280 7892
      4284 7893 4292 7891 4296 7893 4297 7897
      4303 7894 4302 7884 4303 7882 4303 7842
      4257 7845

FLASH FLOOD...RADAR INDICATED

$$

AR
1 follow-up statement
998 
WGUS71 KBUF 130715
FFSBUF

Flash Flood Statement
National Weather Service Buffalo NY
315 AM EDT Mon Sep 13 2021

NYC029-037-121-130725-
/O.CAN.KBUF.FF.W.0023.000000T0000Z-210913T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Erie NY-Genesee NY-Wyoming NY-
315 AM EDT Mon Sep 13 2021

...FLASH FLOOD WARNING IS CANCELLED FOR ERIE, SOUTHWESTERN GENESEE 
AND NORTHWESTERN WYOMING COUNTIES...

Flood waters continue to recede and the heavy rain from earlier has 
ended. Flooding is no longer expected to pose a threat. Please 
continue to heed remaining road closures.

LAT...LON 4258 7919 4272 7909 4276 7899 4280 7892
      4284 7893 4292 7891 4296 7893 4297 7897
      4303 7894 4302 7884 4303 7882 4303 7842
      4257 7845

$$

JLA

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 12, 10:53 PM EDTSpecial Marine WarningBUF82 min
Sep 12, 11:00 PM EDTSevere Thunderstorm Warning Considerable damage threatBUFCattaraugus, Chautauqua, Erie75 min
Sep 12, 11:49 PM EDTSevere Thunderstorm WarningBUFAllegany, Cattaraugus, Chautauqua, Erie, Livingston, Wyoming86 min
Sep 13, 12:09 AM EDTSevere Thunderstorm WarningBUFErie, Genesee, Wyoming66 min
Sep 13, 12:50 AM EDTSevere Thunderstorm WarningBUFLivingston, Ontario55 min
Sep 13, 1:09 AM EDTSpecial Weather StatementBUFGenesee, Monroe, Ontario, Wayne66 min

Nearby

Flash Flood Warnings in New York, 2021Every flash flood warning in 2021

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.