Alert archive / New York / Tornado Watches in 2012
Tornado Watch 645
The Storm Prediction Center issued this tornado watch at Sep 18, 2012, 1:21 PM EDT for 10 counties in New York. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 18, 2012, 1:21 PM EDT (17:21 UTC)
- Expired
- Sep 18, 2012, 6:09 PM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 0.5 in
- Strongest gust expected
- 60 kt
Counties Broome County, NY, Chenango County, NY, Cortland County, NY, Delaware County, NY, Madison County, NY, Oneida County, NY, Onondaga County, NY, Otsego County, NY, Tioga County, NY, Tompkins County, NY
The radar
The Binghamton radar (KBGM), 60 km from the middle of the area, began a volume at 17:24 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
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 18, 1:28 PM EDT | Severe Thunderstorm Warning | BGM | Cayuga, Cortland, Onondaga, Tompkins | 62 min |
| Sep 18, 2:01 PM EDT | Severe Thunderstorm Warning | BGM | Chemung, Cortland, Madison, Oneida, Onondaga, Tioga and 1 more | 59 min |
| Sep 18, 2:51 PM EDT | Severe Thunderstorm Warning | BGM | Madison, Oneida | 54 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
Albany, NY (KALY), launched 12:00Z, 5.4 hours before the alert went out and 163 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
- 2 J/kg
- Mixed-layer CIN
- -126 J/kg
- Mixed-layer LCL
- 572 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km storm-relative helicity
- 251 m²/s²
- 0-3 km storm-relative helicity
- 226 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
248
WWUS20 KWNS 181717
SEL5
SPC WW 181717
NYZ000-182300-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 645
NWS STORM PREDICTION CENTER NORMAN OK
120 PM EDT TUE SEP 18 2012
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
SOUTH-CENTRAL NEW YORK
EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 120 PM UNTIL
700 PM EDT.
TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 50 STATUTE
MILES EAST AND WEST OF A LINE FROM 10 MILES WEST NORTHWEST OF
UTICA NEW YORK TO 20 MILES SOUTHEAST OF BINGHAMTON NEW YORK. FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU5).
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.
OTHER WATCH INFORMATION...CONTINUE...WW 641...WW 642...WW
643...WW 644...
DISCUSSION...A FORCED CONVECTIVE BAND OVER S-CNTRL NY IS EXPECTED TO
INTENSIFY AND GRADUAL DEVELOP NWD WHILE AT THE SAME TIME ADVANCING
EWD. AMBIENT ENVIRONMENT IS ONLY MARGINALLY UNSTABLE BUT STRONGLY
SHEARED AND FORCED WHICH WILL PROMOTE EMBEDDED LEWP STRUCTURES AND
MESOVORTICES CAPABLE OF DAMAGING WINDS AND POSSIBLY TORNADOES.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
350. MEAN STORM MOTION VECTOR 23040.
...MEADSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 18, 11:14 AM EDT | Mesoscale Discussion | SPC | Bronx, Dutchess, Kings, Nassau, New York, Orange and 5 more | 91 min |
| Sep 18, 11:19 AM EDT | Mesoscale Discussion | SPC | Albany, Broome, Chenango, Delaware, Fulton, Greene and 8 more | 86 min |
| Sep 18, 12:10 PM EDT | Tornado Watch | SPC | Bronx, Kings, New York, Orange, Queens, Richmond and 2 more | 9 hr |
| Sep 18, 12:57 PM EDT | Mesoscale Discussion | SPC | Albany, Broome, Chemung, Chenango, Columbia, Cortland and 11 more | 93 min |
| Sep 18, 1:56 PM EDT | Mesoscale Discussion | SPC | Kings, New York, Orange, Richmond, Rockland | 64 min |
| Sep 18, 2:10 PM EDT | Mesoscale Discussion | SPC | Clinton, Essex, Franklin, Fulton, Hamilton, Herkimer and 6 more | 95 min |
| Sep 18, 3:26 PM EDT | Mesoscale Discussion | SPC | Albany, Columbia, Dutchess, Essex, Franklin, Fulton and 11 more | 34 min |
| Sep 18, 3:38 PM EDT | Tornado Watch | SPC | Albany, Columbia, Dutchess, Fulton, Greene, Hamilton and 13 more | 8 hr |
| Sep 18, 4:21 PM EDT | Mesoscale Discussion | SPC | Albany, Bronx, Chenango, Columbia, Delaware, Dutchess and 24 more | 114 min |
| Sep 18, 6:08 PM EDT | Mesoscale Discussion | SPC | Bronx, Kings, New York, Queens, Richmond | 67 min |
| Sep 18, 7:42 PM EDT | Mesoscale Discussion | SPC | Bronx, Kings, Nassau, Putnam, Queens, Suffolk and 1 more | 63 min |
Nearby
Tornado Watches in New York, 2012Every tornado watch in 2012
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.