Alert archive / New York / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 41, NWS New York, NY
NWS New York, NY issued this severe thunderstorm warning at Aug 11, 1999, 4:36 PM EDT for Rockland County, Westchester County, New York. It was in force for 39 min. 2 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Aug 11, 1999, 4:36 PM EDT (20:36 UTC)
- Expired
- Aug 11, 1999, 5:15 PM EDT
- In force
- 39 min
- Issued by
- NWS New York, NY
- Area
- Whole counties
Counties Rockland County, NY, Westchester County, NY
The radar
The Brookhaven radar (KOKX), 92 km from the middle of the area, began a volume at 20:37 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 |
|---|---|---|---|
| Aug 11, 4:37 PM EDT | Thunderstorm Wind 50 | Stony Pt, NY | |
| Aug 11, 5:19 PM EDT | Thunderstorm Wind 52 | Congers, NY |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 8.6 hours before the alert went out and 92 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
- 214 J/kg
- Mixed-layer CIN
- -33 J/kg
- Mixed-layer LCL
- 886 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 194 m²/s²
- 0-3 km storm-relative helicity
- 280 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.6
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS New York, NY wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 11, 3:00 PM EDT, 1 hour 36 minutes earlier.
Area forecast discussion, Aug 11, 3:00 PM EDT, 1 hour 36 minutes before
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Local storm report, Aug 11, 1:04 PM EDT, 3 hours 32 minutes before
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</html>The office that day
Everything else NWS New York, NY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 9:15 AM EDT | Severe Thunderstorm Warning | OKX | Suffolk | 75 min |
| Aug 11, 9:17 AM EDT | Flash Flood Warning | OKX | Suffolk | 3 hr |
| Aug 11, 12:30 PM EDT | Flash Flood Warning | OKX | Suffolk | 3 hr |
| Aug 11, 5:05 PM EDT | Severe Thunderstorm Warning | OKX | Richmond | 60 min |
| Aug 11, 5:05 PM EDT | Severe Thunderstorm Warning | OKX | Kings | 60 min |
| Aug 11, 5:16 PM EDT | Severe Thunderstorm Warning | OKX | Rockland | 64 min |
| Aug 11, 5:52 PM EDT | Severe Thunderstorm Warning | OKX | Westchester | 63 min |
| Aug 11, 7:07 PM EDT | Severe Thunderstorm Warning | OKX | Essex, Passaic | 43 min |
Nearby
Severe Thunderstorm Warnings in New York, 1999Every severe thunderstorm warning in 1999
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.