Alert archive / New York / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 73, NWS Buffalo, NY

July 29, 2020Allegany County, Livingston County, Ontario County, New York

NWS Buffalo, NY issued this severe thunderstorm warning at Jul 29, 2020, 3:45 PM EDT for Allegany County, Livingston County, Ontario County, New York. It was in force for 45 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 29, 2020, 3:45 PM EDT (19:45 UTC)
Expired: Jul 29, 2020, 4:30 PM EDT
In force: 45 min
Issued by: NWS Buffalo, NY
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Allegany County, NY, Livingston County, NY, Ontario County, NY

The radar

The Buffalo radar (KBUF), 99 km from the middle of the area, began a volume at 19:49 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, 7.8 hours before the alert went out and 96 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: 95 J/kg
Mixed-layer CIN: -33 J/kg
Mixed-layer LCL: 995 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 59 m²/s²
0-3 km storm-relative helicity: 217 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted.

403 
WUUS51 KBUF 291945
SVRBUF
NYC003-051-069-292030-
/O.NEW.KBUF.SV.W.0073.200729T1945Z-200729T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Buffalo NY
345 PM EDT Wed Jul 29 2020

The National Weather Service in Buffalo has issued a

* Severe Thunderstorm Warning for...
  Southeastern Livingston County in western New York...
  Northeastern Allegany County in western New York...
  Southwestern Ontario County in western New York...

* Until 430 PM EDT..

* At 344 PM EDT, severe thunderstorms were located along a line
  extending from near Conesus to 7 miles east of Belfast, moving east
  at 30 mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Dansville, Naples, Groveland, Springwater, Ossian, Canaseraga,
  Birdsall, Ossian Center, Hunt Hollow and Swain.

 This includes Interstate 390 between exits 4 and 5.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in Buffalo.

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4268 7777 4267 7736 4267 7737 4258 7737
      4258 7766 4253 7766 4253 7772 4235 7773
      4234 7799
TIME...MOT...LOC 1944Z 250DEG 28KT 4265 7773 4234 7796 

HAIL...0.75IN
WIND...60MPH
 
$$

Fries

2 follow-up statements

311 
WWUS51 KBUF 292005
SVSBUF

Severe Weather Statement
National Weather Service Buffalo NY
405 PM EDT Wed Jul 29 2020

NYC003-292015-
/O.CAN.KBUF.SV.W.0073.000000T0000Z-200729T2030Z/
Allegany NY-
405 PM EDT Wed Jul 29 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN ALLEGANY COUNTY
IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 4267 7736 4267 7737 4258 7737 4258 7766
      4268 7763
TIME...MOT...LOC 2005Z 261DEG 29KT 4268 7754 4254 7764 

$$

NYC051-069-292030-
/O.CON.KBUF.SV.W.0073.000000T0000Z-200729T2030Z/
Livingston NY-Ontario NY-
405 PM EDT Wed Jul 29 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM EDT
FOR SOUTHEASTERN LIVINGSTON AND SOUTHWESTERN ONTARIO COUNTIES...

At 405 PM EDT, severe thunderstorms were located along a line
extending from 7 miles east of Conesus to near Wayland, moving east
at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Naples, Springwater and Hunt Hollow. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Buffalo.

&&

LAT...LON 4267 7736 4267 7737 4258 7737 4258 7766
      4268 7763
TIME...MOT...LOC 2005Z 261DEG 29KT 4268 7754 4254 7764 

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

Fries

207 
WWUS51 KBUF 292014
SVSBUF

Severe Weather Statement
National Weather Service Buffalo NY
414 PM EDT Wed Jul 29 2020

NYC051-292023-
/O.CAN.KBUF.SV.W.0073.000000T0000Z-200729T2030Z/
Livingston NY-
414 PM EDT Wed Jul 29 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN LIVINGSTON COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4258 7749 4267 7748 4267 7737 4258 7737
TIME...MOT...LOC 2013Z 267DEG 31KT 4263 7741 

$$

NYC069-292030-
/O.CON.KBUF.SV.W.0073.000000T0000Z-200729T2030Z/
Ontario NY-
414 PM EDT Wed Jul 29 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM EDT
FOR SOUTHWESTERN ONTARIO COUNTY...

At 413 PM EDT, a severe thunderstorm was located over Naples, or 15
miles east of Dansville, moving east at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Naples and Hunt Hollow. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Buffalo.

&&

LAT...LON 4258 7749 4267 7748 4267 7737 4258 7737
TIME...MOT...LOC 2013Z 267DEG 31KT 4263 7741 

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

Fries

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 29, 4:20 AM EDT	Small Craft Advisory	BUF		16 hr
Jul 29, 10:06 AM EDT	Special Weather Statement	BUF	Erie	54 min
Jul 29, 10:51 AM EDT	Special Weather Statement	BUF	Genesee	54 min
Jul 29, 10:55 AM EDT	Special Marine Warning	BUF		23 min
Jul 29, 11:35 AM EDT	Special Weather Statement	BUF	Livingston	55 min
Jul 29, 11:51 AM EDT	Special Weather Statement	BUF	Wyoming	54 min
Jul 29, 12:21 PM EDT	Special Weather Statement	BUF	Wyoming	39 min
Jul 29, 12:26 PM EDT	Special Weather Statement	BUF	Ontario	34 min
Jul 29, 1:09 PM EDT	Special Weather Statement	BUF	Livingston	36 min
Jul 29, 1:19 PM EDT	Severe Thunderstorm Warning	BUF	Allegany, Livingston, Ontario	41 min
Jul 29, 1:28 PM EDT	Severe Thunderstorm Warning	BUF	Chautauqua	62 min
Jul 29, 1:48 PM EDT	Special Marine Warning	BUF		42 min
Jul 29, 2:10 PM EDT	Severe Thunderstorm Warning	BUF	Cattaraugus, Chautauqua	65 min
Jul 29, 2:13 PM EDT	Special Weather Statement	BUF	Erie	32 min
Jul 29, 2:25 PM EDT	Special Marine Warning	BUF		50 min
Jul 29, 2:49 PM EDT	Severe Thunderstorm Warning	BUF	Allegany, Cattaraugus, Erie, Livingston, Wyoming	56 min
Jul 29, 2:53 PM EDT	Special Weather Statement	BUF	Erie, Wyoming	52 min
Jul 29, 3:27 PM EDT	Severe Thunderstorm Warning	BUF	Livingston, Wyoming	48 min
Jul 29, 3:41 PM EDT	Severe Thunderstorm Warning	BUF	Livingston, Ontario	64 min
Jul 29, 4:15 PM EDT	Special Weather Statement	BUF	Monroe	45 min
Jul 29, 4:20 PM EDT	Severe Thunderstorm Warning	BUF	Cayuga, Ontario, Wayne	40 min
Jul 29, 4:40 PM EDT	Severe Thunderstorm Warning	BUF	Monroe, Wayne	38 min
Jul 29, 4:56 PM EDT	Severe Thunderstorm Warning	BUF	Cayuga, Oswego, Wayne	64 min
Jul 29, 5:35 PM EDT	Special Weather Statement	BUF	Genesee	25 min
Jul 29, 5:42 PM EDT	Severe Thunderstorm Warning	BUF	Genesee, Orleans	48 min
Jul 29, 6:34 PM EDT	Special Weather Statement	BUF	Livingston	26 min
Jul 29, 6:37 PM EDT	Severe Thunderstorm Warning	BUF	Genesee, Livingston, Monroe, Ontario	51 min
Jul 29, 6:41 PM EDT	Severe Thunderstorm Warning	BUF	Genesee, Orleans	34 min
Jul 29, 6:50 PM EDT	Tornado Warning	BUF	Livingston, Monroe, Ontario	28 min

Nearby

Severe Thunderstorm Warnings in New York, 2020 Every severe thunderstorm warning in 2020

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.