Alert archive / Ohio / Severe Thunderstorm Watches in 2012
Severe Thunderstorm Watch 77
The Storm Prediction Center issued this severe thunderstorm watch at Mar 15, 2012, 5:28 PM EDT for 8 counties in Indiana; 10 counties in Kentucky; 19 counties in Ohio. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 15, 2012, 5:28 PM EDT (21:28 UTC)
- Expired
- Mar 15, 2012, 8:10 PM EDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 37 counties
Dearborn County, IN, Fayette County, IN, Franklin County, IN, Ohio County, IN, Ripley County, IN, Switzerland County, IN, Union County, IN, Wayne County, IN, Boone County, KY, Bracken County, KY, Campbell County, KY, Carroll County, KY, Gallatin County, KY, Grant County, KY, Kenton County, KY, Owen County, KY, Pendleton County, KY, Robertson County, KY, Auglaize County, OH, Brown County, OH, Butler County, OH, Champaign County, OH, Clark County, OH, Clermont County, OH, Clinton County, OH, Darke County, OH, Greene County, OH, Hamilton County, OH, Hardin County, OH, Logan County, OH, Mercer County, OH, Miami County, OH, Montgomery County, OH, Preble County, OH, Shelby County, OH, Union County, OH, Warren County, OH
The radar
The Cincinnati radar (KILN), 52 km from the middle of the area, began a volume at 21:28 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
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 50%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
10 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 15, 5:40 PM EDT | Severe Thunderstorm Warning | ILN | Switzerland | 35 min |
| Mar 15, 5:42 PM EDT | Severe Thunderstorm Warning | ILN | Logan, Shelby | 48 min |
| Mar 15, 5:45 PM EDT | Severe Thunderstorm Warning | ILN | Bracken, Pendleton | 45 min |
| Mar 15, 5:46 PM EDT | Severe Thunderstorm Warning | ILN | Fayette, Union, Wayne | 44 min |
| Mar 15, 5:59 PM EDT | Severe Thunderstorm Warning | ILN | Dearborn, Ohio, Switzerland | 46 min |
| Mar 15, 6:06 PM EDT | Flash Flood Warning | ILN | Dearborn, Ohio, Ripley, Switzerland | 2 hr |
| Mar 15, 6:09 PM EDT | Severe Thunderstorm Warning | ILN | Bracken, Mason, Pendleton, Robertson | 36 min |
| Mar 15, 6:25 PM EDT | Severe Thunderstorm Warning | ILN | Logan, Shelby | 33 min |
| Mar 15, 6:29 PM EDT | Severe Thunderstorm Warning | ILN | Bracken, Campbell, Kenton, Pendleton | 46 min |
| Mar 15, 6:42 PM EDT | Severe Thunderstorm Warning | ILN | Butler, Montgomery, Preble, Warren | 32 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
Cncnati-Daytn, OH (KILN), launched 12:00Z, 9.5 hours before the alert went out and 53 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
- 1236 J/kg
- Mixed-layer CIN
- -110 J/kg
- Mixed-layer LCL
- 1005 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 133 m²/s²
- 0-3 km storm-relative helicity
- 137 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.2
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 152126
SEL7
SPC WW 152126
INZ000-KYZ000-OHZ000-160200-
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 77
NWS STORM PREDICTION CENTER NORMAN OK
530 PM EDT THU MAR 15 2012
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
EXTREME EASTERN INDIANA
NORTHERN KENTUCKY
WESTERN OHIO
EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 530 PM UNTIL
1000 PM EDT.
HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 40
STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES NORTH OF
DAYTON OHIO TO 55 MILES SOUTH SOUTHWEST OF CINCINNATI OHIO. FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU7).
REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.
OTHER WATCH INFORMATION...CONTINUE...WW 75...WW 76...
DISCUSSION...SCATTERED THUNDERSTORMS OVER SOUTHERN IN AND KY WILL
SPREAD EASTWARD INTO WESTERN OH THIS EVENING. STEEP LAPSE RATES AND
COOL TEMPERATURES ALOFT...COMBINED WITH A MOIST BOUNDARY
LAYER...WILL PROMOTE VIGOROUS UPDRAFTS AND THE POTENTIAL FOR HAIL IN
THE STRONGER STORMS. EASTWARD PROGRESS OF THE ACTIVITY IS EXPECTED
TO BE LIMITED AS STORMS INTERACT WITH A MORE STABLE AIR MASS OVER
CENTRAL/EASTERN OH LATER THIS EVENING.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 24025.
...HARTSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 15, 2:08 PM EDT | Mesoscale Discussion | SPC | Brown, Clark, Crawford, Daviess, Dubois, Floyd and 20 more | 2 hr |
| Mar 15, 3:06 PM EDT | Severe Thunderstorm Watch | SPC | Clark, Crawford, Dubois, Floyd, Harrison, Jefferson and 4 more | 6 hr |
| Mar 15, 4:44 PM EDT | Mesoscale Discussion | SPC | Bartholomew, Clark, Dearborn, Decatur, Fayette, Floyd and 17 more | 61 min |
| Mar 15, 6:02 PM EDT | Mesoscale Discussion | SPC | Adams, Allen, Cass, DeKalb, Elkhart, Fulton and 19 more | 2 hr |
| Mar 15, 7:23 PM EDT | Mesoscale Discussion | SPC | Bath, Bell, Bourbon, Bracken, Breathitt, Campbell and 36 more | 97 min |
| Mar 15, 3:19 AM EDT | Mesoscale Discussion | SPC | Allen, Ashland, Champaign, Clark, Coshocton, Crawford and 41 more | 86 min |
| Mar 15, 3:52 PM EDT | Mesoscale Discussion | SPC | Allen, Defiance, Fulton, Hancock, Henry, Lucas and 8 more | 83 min |
Nearby
Severe Thunderstorm Watches in Ohio, 2012Severe Thunderstorm Watches in Kentucky, 2012Severe Thunderstorm Watches in Indiana, 2012Every severe thunderstorm 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.