Alert archive / New York / Severe Thunderstorm Warnings in 2004

Severe Thunderstorm Warning 21, NWS Buffalo, NY

May 20, 2004Livingston County, New York

NWS Buffalo, NY issued this severe thunderstorm warning at May 20, 2004, 8:40 PM EDT for Livingston County, New York. It was in force for 65 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: May 20, 2004, 8:40 PM EDT (00:40 UTC)
Expired: May 20, 2004, 9:45 PM EDT
In force: 65 min
Issued by: NWS Buffalo, NY
Area: Counties, with a storm outline in the text

County Livingston County, NY

The radar

The Buffalo radar (KBUF), 77 km from the middle of the area, began a volume at 00:42 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 00:00Z, 0.7 hours before the alert went out and 74 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: 1163 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 875 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 284 m²/s²
0-3 km storm-relative helicity: 339 m²/s²
Significant tornado parameter: 2.2
Supercell composite: 9.4

Open this sounding in Storm Lab

The text

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

077 
WUUS51 KBUF 210040
SVRBUF
NYC051-210145-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BUFFALO NY
841 PM EDT THU MAY 20 2004

THE NATIONAL WEATHER SERVICE IN BUFFALO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  LIVINGSTON COUNTY IN WESTERN NEW YORK

* UNTIL 945 PM EDT

* AT 837 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM.  THIS STORM WAS LOCATED 6 MILES WEST OF
  CALEDONIA...OR ABOUT 11 MILES EAST OF BATAVIA...AND WAS MOVING
  SOUTHEAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  CALEDONIA AT 845 PM EDT...
  YORK AT 850 PM EDT...
  AVON AT 900 PM EDT...
  LIMA AT 915 PM EDT...

DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN BUFFALO.

LAT...LON 4283 7783 4289 7796 4291 7793 4295 7793
          4299 7789 4298 7773 4294 7775 4294 7757
          4287 7756 4279 7770

$$

SAGE

The office that day

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

Issued	Product	Office	Counties	Lasted
May 20, 8:29 PM EDT	Severe Thunderstorm Warning	BUF	Genesee	31 min
May 21, 12:56 AM EDT	Flash Flood Warning	BUF	Allegany	2 hr
May 21, 2:25 AM EDT	Severe Thunderstorm Warning	BUF	Cattaraugus, Chautauqua	50 min
May 21, 2:28 AM EDT	Severe Thunderstorm Warning	BUF	Chautauqua	47 min
May 21, 5:45 AM EDT	Flash Flood Warning	BUF	Chautauqua	3 hr

Nearby

Severe Thunderstorm Warnings in New York, 2004 Every severe thunderstorm warning in 2004

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.