Alert archive / New York / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 399
The Storm Prediction Center issued this severe thunderstorm watch at May 29, 2011, 8:52 PM EDT for 27 counties in New York. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- May 29, 2011, 8:52 PM EDT (00:52 UTC)
- Expired
- May 30, 2011, 1:27 AM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 27 counties
Allegany County, NY, Broome County, NY, Cattaraugus County, NY, Cayuga County, NY, Chautauqua County, NY, Chemung County, NY, Chenango County, NY, Cortland County, NY, Erie County, NY, Genesee County, NY, Livingston County, NY, Madison County, NY, Monroe County, NY, Niagara County, NY, Oneida County, NY, Onondaga County, NY, Ontario County, NY, Orleans County, NY, Oswego County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Tioga County, NY, Tompkins County, NY, Wayne County, NY, Wyoming County, NY, Yates County, NY
The radar
The Buffalo radar (KBUF), 63 km from the middle of the area, began a volume at 00:52 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
11 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 29, 9:17 PM EDT | Severe Thunderstorm Warning | BUF | Cattaraugus, Chautauqua | 58 min |
| May 29, 10:04 PM EDT | Severe Thunderstorm Warning | BUF | Allegany, Cattaraugus | 56 min |
| May 29, 10:21 PM EDT | Severe Thunderstorm Warning | BUF | Allegany, Genesee, Livingston, Wyoming | 34 min |
| May 29, 10:27 PM EDT | Severe Thunderstorm Warning | BUF | Genesee, Livingston, Monroe, Ontario, Orleans | 63 min |
| May 29, 10:30 PM EDT | Severe Thunderstorm Warning | BUF | Allegany | 26 min |
| May 29, 10:34 PM EDT | Severe Thunderstorm Warning | BGM | Steuben, Yates | 41 min |
| May 29, 10:41 PM EDT | Severe Thunderstorm Warning | BUF | Genesee, Livingston, Ontario, Wyoming | 50 min |
| May 29, 11:08 PM EDT | Severe Thunderstorm Warning | BGM | Cayuga, Chemung, Schuyler, Seneca, Steuben, Tompkins and 1 more | 37 min |
| May 29, 11:13 PM EDT | Severe Thunderstorm Warning | BUF | Monroe, Ontario, Wayne | 62 min |
| May 29, 11:36 PM EDT | Severe Thunderstorm Warning | BGM | Broome, Cayuga, Chemung, Cortland, Onondaga, Schuyler and 5 more | 54 min |
| May 29, 11:39 PM EDT | Severe Thunderstorm Warning | BUF | Cayuga, Oswego, Wayne | 66 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Buffalo Intl Airport, NY (KBUF), launched 00:00Z, 0.9 hours before the alert went out and 59 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.
- Mixed-layer CAPE
- 1339 J/kg
- Mixed-layer CIN
- -79 J/kg
- Mixed-layer LCL
- 834 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 118 m²/s²
- 0-3 km storm-relative helicity
- 136 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.4
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 29, 9:47 PM EDT | Mesoscale Discussion | SPC | Allegany, Cattaraugus, Cayuga, Chautauqua, Chemung, Cortland and 17 more | 58 min |
| May 30, 12:28 AM EDT | Mesoscale Discussion | SPC | Albany, Broome, Cayuga, Chemung, Chenango, Columbia and 20 more | 92 min |
| May 30, 3:46 AM EDT | Mesoscale Discussion | SPC | Bronx, Kings, New York, Orange, Queens, Richmond and 3 more | 119 min |
Nearby
Severe Thunderstorm Watches in New York, 2011Every severe thunderstorm watch in 2011
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.