Alert archive / New York / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 90, NWS Buffalo, NY

August 20, 2009Genesee County, Monroe County, Orleans County, New York

NWS Buffalo, NY issued this severe thunderstorm warning at Aug 20, 2009, 10:04 PM EDT for Genesee County, Monroe County, Orleans County, New York. It was in force for 56 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: Aug 20, 2009, 10:04 PM EDT (02:04 UTC)
Expired: Aug 20, 2009, 11:00 PM EDT
In force: 56 min
Issued by: NWS Buffalo, NY
Area: Storm-based polygon

Counties Genesee County, NY, Monroe County, NY, Orleans County, NY

The radar

The Buffalo radar (KBUF), 71 km from the middle of the area, began a volume at 02:04 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 watch it was issued in

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

Issued	Product	Office	Lasted
Aug 20, 6:54 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 00:00Z, 2.1 hours before the alert went out and 69 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: 828 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 1273 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 232 m²/s²
0-3 km storm-relative helicity: 306 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 6.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS51 KBUF 210204
SVRBUF
NYC037-055-073-210300-
/O.NEW.KBUF.SV.W.0090.090821T0204Z-090821T0300Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BUFFALO NY
1004 PM EDT THU AUG 20 2009

THE NATIONAL WEATHER SERVICE IN BUFFALO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN GENESEE COUNTY IN WESTERN NEW YORK
  WESTERN MONROE COUNTY IN WESTERN NEW YORK
  SOUTHEASTERN ORLEANS COUNTY IN WESTERN NEW YORK

* UNTIL 1100 PM EDT

* AT 1000 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM 5 MILES NORTHEAST OF OAKFIELD TO 6 MILES SOUTHWEST OF         
  BATAVIA...AND MOVING NORTHEAST AT 40 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  ALBION BY 1010 PM EDT...
  BYRON BY 1015 PM EDT...
  HOLLEY...KENDALL AND LE ROY BY 1020 PM EDT...
  BROCKPORT BY 1025 PM EDT...
  HAMLIN BEACH AND CHURCHVILLE BY 1030 PM EDT...
  SPENCERPORT AND SCOTTSVILLE BY 1035 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THESE STORMS. MOVE INDOORS
IMMEDIATELY LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT 
TONIGHT FOR WESTERN NEW YORK.

&&

LAT...LON 4321 7830 4337 7790 4336 7784 4334 7781
      4335 7776 4334 7772 4329 7766 4302 7769
      4299 7785 4299 7790 4297 7790 4289 7831
TIME...MOT...LOC 0204Z 242DEG 36KT 4315 7818 4295 7819

$$

HITCHCOCK

2 follow-up statements

000 
WWUS51 KBUF 210232
SVSBUF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
1032 PM EDT THU AUG 20 2009

NYC037-055-073-210300-
/O.CON.KBUF.SV.W.0090.000000T0000Z-090821T0300Z/
GENESEE NY-MONROE NY-ORLEANS NY-
1032 PM EDT THU AUG 20 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT
FOR SOUTHEASTERN ORLEANS...WESTERN MONROE AND EASTERN GENESEE
COUNTIES...

AT 1030 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM HILTON TO STAFFORD...OR ALONG A LINE EXTENDING FROM
HILTON TO BATAVIA...MOVING NORTHEAST AT 35 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  BRADDOCK BAY AND LE ROY AND BERGEN BY 1040 PM EDT...
  SPENCERPORT AND CHURCHVILLE BY 1045 PM EDT...
  MUMFORD BY 1050 PM EDT...
  SCOTTSVILLE AND GREECE BY 1055 PM EDT...
  GATES-NORTH GATES AND GATES BY 1100 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THESE STORMS. MOVE INDOORS
IMMEDIATELY LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT 
TONIGHT FOR WESTERN NEW YORK.

&&

LAT...LON 4291 7826 4336 7791 4336 7784 4334 7781
      4335 7776 4334 7771 4329 7766 4302 7769
      4299 7785 4299 7790 4297 7791
TIME...MOT...LOC 0232Z 241DEG 32KT 4327 7781 4297 7810

$$

HITCHCOCK

000 
WWUS51 KBUF 210257
SVSBUF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
1057 PM EDT THU AUG 20 2009

NYC037-055-073-210307-
/O.EXP.KBUF.SV.W.0090.000000T0000Z-090821T0300Z/
GENESEE NY-MONROE NY-ORLEANS NY-
1057 PM EDT THU AUG 20 2009

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN ORLEANS...WESTERN
MONROE AND EASTERN GENESEE COUNTIES WILL EXPIRE AT 1100 PM EDT...

AT 1057 PM EDT NATIONAL WEATHER SERVICE RADAR SHOWED THAT THE SEVERE
THUNDERSTORM THAT PROMPTED THE WARNING HAD WEAKENED AND WAS NO LONGER
SEVERE...THUS THE WARNING HAS BEEN ALLOWED TO EXPIRE.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT 
TONIGHT FOR WESTERN NEW YORK.

LAT...LON 4291 7826 4336 7791 4336 7784 4334 7781
      4335 7776 4334 7771 4329 7766 4302 7769
      4299 7785 4299 7790 4297 7791
TIME...MOT...LOC 0257Z 241DEG 32KT 4337 7754 4308 7784

$$

HITCHCOCK

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 20, 8:31 PM EDT	Special Marine Warning	BUF		44 min
Aug 20, 8:31 PM EDT	Severe Thunderstorm Warning	BUF	Orleans	59 min
Aug 20, 8:52 PM EDT	Areal Flood Advisory	BUF	Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Niagara and 2 more	3 hr
Aug 20, 8:59 PM EDT	Severe Thunderstorm Warning	BUF	Cattaraugus, Chautauqua	61 min
Aug 20, 9:16 PM EDT	Special Marine Warning	BUF		89 min
Aug 20, 9:52 PM EDT	Severe Thunderstorm Warning	BUF	Allegany, Cattaraugus	53 min
Aug 20, 10:06 PM EDT	Severe Thunderstorm Warning	BUF	Allegany	54 min
Aug 20, 10:19 PM EDT	Special Marine Warning	BUF		86 min
Aug 20, 10:25 PM EDT	Tornado Warning	BUF	Allegany	35 min
Aug 20, 11:28 PM EDT	Special Marine Warning	BUF		92 min

Nearby

Severe Thunderstorm Warnings in New York, 2009 Every severe thunderstorm warning in 2009

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.