Alert archive / New York / Flash Flood Watches in 2021

Flash Flood Watch 1, NWS Buffalo, NY

July 12, 2021Allegany County, Cattaraugus County, Chautauqua County, New York

NWS Buffalo, NY issued this flash flood watch at Jul 12, 2021, 9:02 AM EDT for Allegany County, Cattaraugus County, Chautauqua County, New York. It took effect at Jul 12, 2021, 2:00 PM EDT. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued
Jul 12, 2021, 9:02 AM EDT (13:02 UTC)
In effect from
Jul 12, 2021, 2:00 PM EDT
Expired
Jul 12, 2021, 9:12 PM EDT
In force
7 hr
Issued by
NWS Buffalo, NY
Flood severity
None

Counties Allegany County, NY, Cattaraugus County, NY, Chautauqua County, NY

The radar

The Buffalo radar (KBUF), 76 km from the middle of the area, began a volume at 13:05 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, 1.0 hours before the alert went out and 73 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 2021-07-12Temperature 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 2021-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
524 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
114 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

887 
WGUS61 KBUF 121302
FFABUF

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Buffalo NY
902 AM EDT Mon Jul 12 2021

.A warm front will result in another round of showers and 
thunderstorms with heavy rain across the Southern Tier this 
afternoon into early this evening. Additional heavy rain combined 
with the recent heavy rainfall could produce flooding in some areas.

NYZ019>021-122115-
/O.NEW.KBUF.FF.A.0001.210712T1800Z-210713T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chautauqua-Cattaraugus-Allegany-
Including the cities of Jamestown, Olean, and Wellsville
902 AM EDT Mon Jul 12 2021

...FLASH FLOOD WATCH IN EFFECT FROM 2 PM EDT THIS AFTERNOON THROUGH 
THIS EVENING...

The National Weather Service in Buffalo has issued a

* Flash Flood Watch for a portion of western New York, including the 
  following counties, Allegany, Cattaraugus and Chautauqua.

* From 2 PM EDT this afternoon through this evening.

* Recent heavy rainfall of 1 to 2 inches since Sunday morning 
  combined with heavy rain from additional showers and thunderstorms 
  this afternoon into early this evening may result in flooding 
  across the Southern Tier.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

JLA
2 follow-up statements
659 
WGUS61 KBUF 121942
FFABUF

Flood Watch
National Weather Service Buffalo NY
342 PM EDT Mon Jul 12 2021

NYZ019>021-130300-
/O.CON.KBUF.FF.A.0001.000000T0000Z-210713T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chautauqua-Cattaraugus-Allegany-
Including the cities of Jamestown, Olean, and Wellsville
342 PM EDT Mon Jul 12 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 11 PM EDT THIS 
EVENING...

The Flash Flood Watch continues for

* A portion of western New York, including the following counties, 
  Allegany, Cattaraugus and Chautauqua.

* Until 11 PM EDT this evening.

* Recent heavy rainfall of 1 to 2 inches since Sunday morning 
  combined with heavy rain from additional showers and thunderstorms 
  into this evening may result in flash flooding across portions of 
  the Southern Tier.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Apffel
143 
WGUS61 KBUF 130112
FFABUF

Flood Watch
National Weather Service Buffalo NY
912 PM EDT Mon Jul 12 2021

NYZ019>021-130215-
/O.CAN.KBUF.FF.A.0001.000000T0000Z-210713T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chautauqua-Cattaraugus-Allegany-
Including the cities of Jamestown, Olean, and Wellsville
912 PM EDT Mon Jul 12 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for a portion of western New York, including 
the following areas, Allegany, Cattaraugus and Chautauqua has been 
cancelled.

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

$$

Apffel

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 12, 2:46 AM EDTSpecial Weather StatementBUFJefferson, Lewis, Oswego89 min
Jul 12, 6:26 PM EDTSpecial Weather StatementBUFChautauqua64 min

Nearby

Flash Flood Watches in New York, 2021Every flash flood watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.