Alert archive / New York / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 68, NWS Buffalo, NY

September 21, 20186 counties in New York

NWS Buffalo, NY issued this severe thunderstorm warning at Sep 21, 2018, 6:31 PM EDT for 6 counties in New York. It was in force for 59 min. 11 reports 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 21, 2018, 6:31 PM EDT (22:31 UTC)
Expired: Sep 21, 2018, 7:30 PM EDT
In force: 59 min
Issued by: NWS Buffalo, NY
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Genesee County, NY, Livingston County, NY, Monroe County, NY, Ontario County, NY, Wayne County, NY, Wyoming County, NY

The radar

The Buffalo radar (KBUF), 97 km from the middle of the area, began a volume at 22:30 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 21, 6:39 PM EDT	TSTM WND DMG	Caledonia, NY	TREE DOWN AND WIRES.
Sep 21, 6:39 PM EDT	NON-TSTM WND DMG	Caledonia, NY	TREE DOWN AND WIRES.
Sep 21, 6:40 PM EDT	TSTM WND DMG	Castile, NY	TREES AND WIRES DOWN.
Sep 21, 6:46 PM EDT	TSTM WND DMG	Avon, NY	WIRES DOWN.
Sep 21, 6:46 PM EDT	TSTM WND DMG	Portageville, NY	GAZEBO DAMAGED BY WIND.
Sep 21, 7:05 PM EDT	TSTM WND DMG	1 Sse Holcomb, NY	MULTIPLE HARDWOOD TREES DOWN, LIMBS DOWN, AND SHINGLES BLOWN OFF A ROOF NEAR US 20 AND FLATIRON ROAD
Sep 21, 7:07 PM EDT	TSTM WND DMG	Bloomfield, NY	TREE AND WIRES DOWN WEST MAIN.
Sep 21, 7:09 PM EDT	TSTM WND DMG	1 E Bloomfield, NY	LARGE TREE DOWN.
Sep 21, 7:10 PM EDT	TSTM WND DMG	2 Ese Holcomb, NY	MOBILE SIGNAGE AND RECREATIONAL DEVICES OVERTURNED
Sep 21, 7:12 PM EDT	TSTM WND DMG	1 W Canandaigua, NY	TREES AND LIMBS DOWN ALONG BUFFALO ST EXT AND N PEARL ST
Sep 21, 7:13 PM EDT	TSTM WND DMG	Dansville, NY	MULTIPLE TREES AND WIRES DOWN.

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 21, 4:50 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 10.5 hours before the alert went out and 93 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: 445 J/kg
Mixed-layer CIN: -72 J/kg
Mixed-layer LCL: 1045 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 334 m²/s²
0-3 km storm-relative helicity: 332 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 4.9

Open this sounding in Storm Lab

The text

As transmitted.

157 
WUUS51 KBUF 212231
SVRBUF
NYC037-051-055-069-117-121-212330-
/O.NEW.KBUF.SV.W.0068.180921T2231Z-180921T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Buffalo NY
631 PM EDT FRI SEP 21 2018

The National Weather Service in Buffalo has issued a

* Severe Thunderstorm Warning for...
  Southwestern Wayne County in western New York...
  Wyoming County in western New York...
  Livingston County in western New York...
  Southern Monroe County in western New York...
  Eastern Genesee County in western New York...
  Ontario County in western New York...

* Until 730 PM EDT..

* At 630 PM EDT, severe thunderstorms were located along a line
  extending from Churchville to 6 miles northeast of Arcade, moving
  northeast at 115 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Rochester, Chili, Geneva, Canandaigua, Geneseo, East Rochester,
  Fairport, Dansville, Brighton and Letchworth State Park.

This includes the following highways...
 Interstate 390 between exits 4 and 12.
 Interstate 90 between exits 47 and 42.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Damaging winds and frequent 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.

Intense thunderstorm lines can produce brief tornadoes and 
widespread significant wind damage. Although a tornado is not 
immediately likely, it is best to move to an interior room on the 
lowest floor of a building. These storms may cause serious injury 
and significant property damage.

&&

LAT...LON 4247 7784 4252 7784 4252 7843 4312 7800
      4314 7697 4276 7699 4276 7731 4267 7737
      4258 7737 4258 7766 4253 7766 4253 7772
      4247 7773
TIME...MOT...LOC 2230Z 236DEG 99KT 4310 7788 4261 7835 

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

RSH

2 follow-up statements

082 
WWUS51 KBUF 212306
SVSBUF

Severe Weather Statement
National Weather Service Buffalo NY
706 PM EDT FRI SEP 21 2018

NYC037-055-121-212315-
/O.CAN.KBUF.SV.W.0068.000000T0000Z-180921T2330Z/
Wyoming NY-Monroe NY-Genesee NY-
706 PM EDT FRI SEP 21 2018

...THE SEVERE THUNDERSTORM WARNING FOR WYOMING...SOUTHERN MONROE AND
EASTERN GENESEE COUNTIES IS CANCELLED...

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

A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
western New York.

LAT...LON 4247 7784 4252 7784 4253 7806 4258 7805
      4259 7801 4260 7803 4267 7795 4281 7796
      4293 7776 4294 7748 4300 7748 4314 7697
      4276 7699 4276 7731 4267 7737 4258 7737
      4258 7766 4253 7766 4253 7772 4247 7773
TIME...MOT...LOC 2305Z 268DEG 49KT 4313 7711 4264 7759 

$$

NYC051-069-117-212330-
/O.CON.KBUF.SV.W.0068.000000T0000Z-180921T2330Z/
Wayne NY-Livingston NY-Ontario NY-
706 PM EDT FRI SEP 21 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM EDT
FOR SOUTHWESTERN WAYNE...LIVINGSTON AND ONTARIO COUNTIES...

At 705 PM EDT, severe thunderstorms were located along a line
extending from near Marion to near Wayland, moving east at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Geneva, Canandaigua, Geneseo, Dansville, Letchworth State Park,
Newark, Lyons, Palmyra, Avon and Mount Morris.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

LAT...LON 4247 7784 4252 7784 4253 7806 4258 7805
      4259 7801 4260 7803 4267 7795 4281 7796
      4293 7776 4294 7748 4300 7748 4314 7697
      4276 7699 4276 7731 4267 7737 4258 7737
      4258 7766 4253 7766 4253 7772 4247 7773
TIME...MOT...LOC 2305Z 268DEG 49KT 4313 7711 4264 7759 

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

Thomas

888 
WWUS51 KBUF 212334
SVSBUF

Severe Weather Statement
National Weather Service Buffalo NY
734 PM EDT FRI SEP 21 2018

NYC051-069-117-212344-
/O.EXP.KBUF.SV.W.0068.000000T0000Z-180921T2330Z/
Wayne NY-Livingston NY-Ontario NY-
734 PM EDT FRI SEP 21 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN WAYNE...
LIVINGSTON AND ONTARIO COUNTIES HAS EXPIRED...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been allowed to expire.

A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
western New York.

LAT...LON 4247 7784 4252 7784 4253 7806 4258 7805
      4259 7801 4260 7803 4267 7795 4281 7796
      4293 7776 4294 7748 4300 7748 4314 7697
      4276 7699 4276 7731 4267 7737 4258 7737
      4258 7766 4253 7766 4253 7772 4247 7773
TIME...MOT...LOC 2334Z 263DEG 47KT 4331 7646 4282 7694 

$$

Thomas

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 20, 10:00 PM EDT	Beach Hazards Statement	BUF	Chautauqua, Erie, Jefferson, Niagara, Orleans	22 hr
Sep 21, 4:45 PM EDT	Special Marine Warning	BUF		60 min
Sep 21, 5:15 PM EDT	Severe Thunderstorm Warning	BUF	Cattaraugus, Chautauqua, Erie	45 min
Sep 21, 5:22 PM EDT	Severe Thunderstorm Warning	BUF	Cattaraugus, Chautauqua	38 min
Sep 21, 5:27 PM EDT	Severe Thunderstorm Warning	BUF	Erie, Genesee, Niagara, Orleans	48 min
Sep 21, 5:54 PM EDT	Severe Thunderstorm Warning	BUF	Allegany, Cattaraugus, Chautauqua, Erie, Wyoming	66 min
Sep 21, 6:38 PM EDT	Special Marine Warning	BUF		70 min
Sep 21, 6:48 PM EDT	Tornado Warning	BUF	Allegany, Cattaraugus	42 min
Sep 21, 6:51 PM EDT	Severe Thunderstorm Warning	BUF	Allegany	54 min
Sep 21, 7:07 PM EDT	Tornado Warning	BUF	Ontario	23 min
Sep 21, 7:29 PM EDT	Special Marine Warning	BUF		46 min

Nearby

Severe Thunderstorm Warnings in New York, 2018 Every severe thunderstorm warning in 2018

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.