Alert archive / New York / Flash Flood Warnings in 2021

Flash Flood Warning 17, NWS Buffalo, NY

August 7, 2021Livingston County, Monroe County, New York

NWS Buffalo, NY issued this flash flood warning at Aug 7, 2021, 6:29 PM EDT for Livingston County, Monroe County, New York. It was in force for 94 min. 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 7, 2021, 6:29 PM EDT (22:29 UTC)
Expired
Aug 7, 2021, 8:03 PM EDT
In force
94 min
Issued by
NWS Buffalo, NY
Area
Storm-based polygon
Flood severity
None

Counties Livingston County, NY, Monroe County, NY

The radar

The Buffalo radar (KBUF), 83 km from the middle of the area, began a volume at 22:33 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 7, 7:02 PM EDTFLASH FLOOD2 Ssw Scottsville, NYSOUTH ROAD AND BOWERMAN ROAD AREAS CLOSED DUE TO WATER OVER ROADWAY.

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, 10.5 hours before the alert went out and 80 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 2021-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 54 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 2021-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 48 square meters per square second.193958Sfc1 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
54 J/kg
Mixed-layer CIN
-138 J/kg
Mixed-layer LCL
1411 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
48 m²/s²
0-3 km storm-relative helicity
55 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

548 
WGUS51 KBUF 072229
FFWBUF
NYC051-055-080130-
/O.NEW.KBUF.FF.W.0017.210807T2229Z-210808T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Buffalo NY
629 PM EDT Sat Aug 7 2021

The National Weather Service in Buffalo has issued a

* Flash Flood Warning for...
  North Central Livingston County in western New York...
  South Central Monroe County in western New York...

* Until 930 PM EDT.

* At 629 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain in excess of 2 inches across 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...
  Henrietta, Avon, Scottsville, Rush, Martin, Industry and Garbutt.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4300 7783 4301 7783 4305 7768 4308 7761
      4302 7754 4292 7773

FLASH FLOOD...RADAR INDICATED

$$

RSH
1 follow-up statement
078 
WGUS71 KBUF 080003
FFSBUF

Flash Flood Statement
National Weather Service Buffalo NY
803 PM EDT Sat Aug 7 2021

NYC051-055-080013-
/O.CAN.KBUF.FF.W.0017.000000T0000Z-210808T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Livingston NY-Monroe NY-
803 PM EDT Sat Aug 7 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTH CENTRAL LIVINGSTON AND 
SOUTH CENTRAL MONROE COUNTIES...

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

LAT...LON 4300 7783 4301 7783 4305 7768 4308 7761
      4302 7754 4292 7773

$$

RSH

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 2:56 PM EDTSpecial Marine WarningBUF94 min
Aug 7, 4:26 PM EDTSpecial Marine WarningBUF94 min
Aug 7, 6:03 PM EDTSpecial Weather StatementBUFMonroe42 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.