Alert archive / New York / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 109, NWS Buffalo, NY

September 13, 2021Livingston County, Ontario County, New York

NWS Buffalo, NY issued this severe thunderstorm warning at Sep 13, 2021, 12:50 AM EDT for Livingston County, Ontario County, New York. It was in force for 55 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: Sep 13, 2021, 12:50 AM EDT (04:50 UTC)
Expired: Sep 13, 2021, 1:45 AM EDT
In force: 55 min
Issued by: NWS Buffalo, NY
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Livingston County, NY, Ontario County, NY

The radar

The Buffalo radar (KBUF), 110 km from the middle of the area, began a volume at 04:52 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

Time	Report	Where	Remark
Sep 13, 12:57 AM EDT	TORNADO	3 Nw Springwater, NY	DOZENS OF HARDWOOD AND SOFTWOOD TREE TRUNKS WERE SHEARED IN HALF WITH DAMAGE TO THE ROOF OF AN OUTDOOR SHED. THE TRACK OF THE TORNADO STARTED JUST WEST OF ROUTE 15 AND ENDED JUST EAST OF MARROWBACK ROAD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Sep 12, 10:25 PM EDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 00:00Z, 4.8 hours before the alert went out and 107 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: 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.

414 
WUUS51 KBUF 130450
SVRBUF
NYC051-069-130545-
/O.NEW.KBUF.SV.W.0109.210913T0450Z-210913T0545Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Buffalo NY
1250 AM EDT Mon Sep 13 2021

The National Weather Service in Buffalo has issued a

* Severe Thunderstorm Warning for...
  Southeastern Livingston County in western New York...
  Central Ontario County in western New York...

* Until 145 AM EDT.

* At 1249 AM EDT, severe thunderstorms were located along a line
  extending from near Geneseo to 7 miles northwest of Dansville to 9
  miles west of Arkport, moving east at 75 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to trees and power lines.

* Locations impacted include...
  Bristol, Naples, Rushville, Honeoye, Hemlock, Gorham, Springwater,
  Canadice, Livonia and Cheshire.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with these storms. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 4285 7767 4285 7698 4276 7697 4276 7731
      4273 7734 4267 7737 4258 7737 4258 7766
      4254 7766 4253 7768
TIME...MOT...LOC 0449Z 281DEG 66KT 4281 7787 4261 7783 4240 7788 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

RSH

1 follow-up statement

326 
WWUS51 KBUF 130537
SVSBUF

Severe Weather Statement
National Weather Service Buffalo NY
137 AM EDT Mon Sep 13 2021

NYC051-069-130546-
/O.EXP.KBUF.SV.W.0109.000000T0000Z-210913T0545Z/
Livingston NY-Ontario NY-
137 AM EDT Mon Sep 13 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN LIVINGSTON AND
CENTRAL ONTARIO COUNTIES WILL EXPIRE AT 145 AM EDT...
    
The storms which prompted the warning have weakened below severe
limits, and have exited the warned area. Therefore, the warning will 
be allowed to expire.  However heavy rain is still expected with 
additional thunderstorms.

A Severe Thunderstorm Watch remains in effect until 200 AM EDT for
western New York.

LAT...LON 4285 7767 4285 7698 4276 7697 4276 7731
      4273 7734 4267 7737 4258 7737 4258 7766
      4254 7766 4253 7768
TIME...MOT...LOC 0536Z 281DEG 66KT 4266 7684 4246 7680 4225 7685 

$$

RSH

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 12, 10:53 PM EDT	Special Marine Warning	BUF		82 min
Sep 12, 11:00 PM EDT	Severe Thunderstorm Warning Considerable damage threat	BUF	Cattaraugus, Chautauqua, Erie	75 min
Sep 12, 11:49 PM EDT	Severe Thunderstorm Warning	BUF	Allegany, Cattaraugus, Chautauqua, Erie, Livingston, Wyoming	86 min
Sep 13, 12:09 AM EDT	Severe Thunderstorm Warning	BUF	Erie, Genesee, Wyoming	66 min
Sep 13, 12:25 AM EDT	Flash Flood Warning	BUF	Erie, Genesee, Wyoming	3 hr
Sep 13, 1:09 AM EDT	Special Weather Statement	BUF	Genesee, Monroe, Ontario, Wayne	66 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.