Alert archive / New York / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 76, NWS Buffalo, NY

July 17, 2021Allegany County, New York

NWS Buffalo, NY issued this severe thunderstorm warning at Jul 17, 2021, 1:48 PM EDT for Allegany County, New York. It was in force for 42 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 17, 2021, 1:48 PM EDT (17:48 UTC)
Expired: Jul 17, 2021, 2:30 PM EDT
In force: 42 min
Issued by: NWS Buffalo, NY
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

County Allegany County, NY

The radar

The Buffalo radar (KBUF), 120 km from the middle of the area, began a volume at 17:49 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, 5.8 hours before the alert went out and 117 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 558 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 32 m²/s²
0-3 km storm-relative helicity: 137 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

279 
WUUS51 KBUF 171748
SVRBUF
NYC003-171830-
/O.NEW.KBUF.SV.W.0076.210717T1748Z-210717T1830Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Buffalo NY
148 PM EDT Sat Jul 17 2021

The National Weather Service in Buffalo has issued a

* Severe Thunderstorm Warning for...
  Southeastern Allegany County in western New York...

* Until 230 PM EDT..

* At 147 PM EDT, a severe thunderstorm was located near Genesee, or
  11 miles south of Wellsville, moving northeast at 25 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Whitesville, Andover, Alma, Stannards and Paynesville. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4200 7807 4202 7808 4218 7774 4200 7775
TIME...MOT...LOC 1747Z 244DEG 21KT 4195 7792 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

Mitchell

2 follow-up statements

932 
WWUS51 KBUF 171811
SVSBUF

Severe Weather Statement
National Weather Service Buffalo NY
211 PM EDT Sat Jul 17 2021

NYC003-171830-
/O.CON.KBUF.SV.W.0076.000000T0000Z-210717T1830Z/
Allegany NY-
211 PM EDT Sat Jul 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 230 PM EDT
FOR SOUTHEASTERN ALLEGANY COUNTY...

At 211 PM EDT, a severe thunderstorm was located over Whitesville, or
11 miles southeast of Wellsville, moving northeast at 25 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Whitesville, Andover, Stannards and Paynesville. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4200 7789 4208 7795 4218 7774 4200 7775
TIME...MOT...LOC 1811Z 242DEG 21KT 4203 7776 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

Mitchell

859 
WWUS51 KBUF 171832
SVSBUF

Severe Weather Statement
National Weather Service Buffalo NY
232 PM EDT Sat Jul 17 2021

NYC003-171842-
/O.EXP.KBUF.SV.W.0076.000000T0000Z-210717T1830Z/
Allegany NY-
232 PM EDT Sat Jul 17 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN ALLEGANY COUNTY
HAS EXPIRED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been allowed to expire.

LAT...LON 4200 7789 4208 7795 4218 7774 4200 7775
TIME...MOT...LOC 1832Z 244DEG 21KT 4208 7762 

$$

Mitchell

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 4:15 AM EDT	Beach Hazards Statement	BUF	Chautauqua, Monroe, Niagara, Orleans, Wayne	32 hr
Jul 17, 4:42 AM EDT	Special Weather Statement	BUF	Chautauqua	48 min
Jul 17, 6:12 AM EDT	Areal Flood Warning	BUF	Erie, Genesee, Livingston, Monroe, Niagara, Orleans and 1 more	13 hr
Jul 17, 7:39 AM EDT	Special Weather Statement	BUF	Chautauqua	36 min
Jul 17, 7:59 AM EDT	Flash Flood Warning	BUF	Chautauqua	3 hr
Jul 17, 9:11 AM EDT	Areal Flood Warning	BUF	Chautauqua	3 hr
Jul 17, 2:10 PM EDT	Areal Flood Warning	BUF	Monroe	40 hr
Jul 17, 3:15 PM EDT	Flash Flood Warning	BUF	Cattaraugus, Erie	6 hr
Jul 17, 3:15 PM EDT	Tornado Warning	BUF	Cattaraugus, Erie	30 min
Jul 17, 3:46 PM EDT	Severe Thunderstorm Warning	BUF	Allegany, Cattaraugus, Erie, Wyoming	44 min
Jul 17, 4:30 PM EDT	Special Weather Statement	BUF	Livingston	45 min
Jul 17, 4:35 PM EDT	River Flood Warning	BUF	Cattaraugus, Chautauqua, Erie, Wyoming	10 hr
Jul 17, 5:15 PM EDT	Areal Flood Warning	BUF	Livingston, Ontario	3 hr
Jul 17, 5:28 PM EDT	Areal Flood Warning	BUF	Allegany, Cattaraugus	5 hr

Nearby

Severe Thunderstorm Warnings in New York, 2021 Every severe thunderstorm 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.