Alert archive / New York / Special Weather Statements in 2021

Special Weather Statement, NWS Buffalo, NY

July 27, 2021Allegany County, New York

NWS Buffalo, NY issued this special weather statement at Jul 27, 2021, 2:02 PM EDT for Allegany County, New York. It was in force for 43 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 27, 2021, 2:02 PM EDT (18:02 UTC)
Expired
Jul 27, 2021, 2:45 PM EDT
In force
43 min
Issued by
NWS Buffalo, NY

County Allegany County, NY

The radar

The Buffalo radar (KBUF), 109 km from the middle of the area, began a volume at 18:04 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, 6.0 hours before the alert went out and 106 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 2021-07-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 15 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 2021-07-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 95 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
15 J/kg
Mixed-layer CIN
-173 J/kg
Mixed-layer LCL
1473 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
95 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

632 
WWUS81 KBUF 271802
SPSBUF

Special Weather Statement
National Weather Service Buffalo NY
202 PM EDT Tue Jul 27 2021

NYZ021-271845-
Allegany-
202 PM EDT Tue Jul 27 2021

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT SOUTHERN ALLEGANY
COUNTY...

At 159 PM EDT, radar indicated strong thunderstorms were located 
along a line extending from near Cuba to near Alfred. While the 
movement of the line of storms is to the southeast at 25 mph, the 
individual thunderstorms are moving east at 35 mph. This scenario 
will encourage multiple storms to pass over the same area thus 
producing multiple bouts of heavy rain. 

Winds in excess of 40 mph are possible with these storms.

Locations impacted include...
Wellsville, Cuba, Whitesville, Friendship, Scio, Bolivar, Andover,
Belmont, Alma, Richburg, Stannards, Knight Creek, West Clarksville,
Paynesville, Little Genesee and Ceres.

This includes Interstate 86 between exits 28 and 29.
 
If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms, and may 
cause localized flooding. Doppler radar estimates that multiple 
rounds of storms will likely produce an average of a half to one 
inch of rain in less than an hour. Do not drive your vehicle through 
flooded roadways.

LAT...LON 4200 7830 4223 7830 4223 7774 4200 7775
TIME...MOT...LOC 1759Z 291DEG 27KT 4216 7825 4221 7777 
$$

RSH

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 27, 10:59 AM EDTSpecial Marine WarningBUF91 min
Jul 27, 11:15 AM EDTSpecial Marine WarningBUF60 min
Jul 27, 1:11 PM EDTSpecial Weather StatementBUFWyoming34 min
Jul 27, 1:48 PM EDTSpecial Weather StatementBUFAllegany27 min

Nearby

Special Weather Statements in New York, 2021Every special weather statement 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.