Alert archive / Ohio / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 710

August 1, 201155 counties in Ohio; 4 counties in West Virginia

The Storm Prediction Center issued this severe thunderstorm watch at Aug 1, 2011, 1:19 PM EDT for 55 counties in Ohio; 4 counties in West Virginia. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Aug 1, 2011, 1:19 PM EDT (17:19 UTC)
Expired
Aug 1, 2011, 7:19 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 59 counties

Allen County, OH, Ashland County, OH, Ashtabula County, OH, Auglaize County, OH, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Coshocton County, OH, Crawford County, OH, Cuyahoga County, OH, Defiance County, OH, Delaware County, OH, Erie County, OH, Fulton County, OH, Geauga County, OH, Guernsey County, OH, Hancock County, OH, Hardin County, OH, Harrison County, OH, Henry County, OH, Holmes County, OH, Huron County, OH, Jefferson County, OH, Knox County, OH, Lake County, OH, Licking County, OH, Logan County, OH, Lorain County, OH, Lucas County, OH, Mahoning County, OH, Marion County, OH, Medina County, OH, Mercer County, OH, Monroe County, OH, Morrow County, OH, Muskingum County, OH, Noble County, OH, Ottawa County, OH, Paulding County, OH, Portage County, OH, Putnam County, OH, Richland County, OH, Sandusky County, OH, Seneca County, OH, Shelby County, OH, Stark County, OH, Summit County, OH, Trumbull County, OH, Tuscarawas County, OH, Union County, OH, Van Wert County, OH, Wayne County, OH, Williams County, OH, Wood County, OH, Wyandot County, OH, Brooke County, WV, Hancock County, WV, Marshall County, WV, Ohio County, WV

The radar

The Cleveland radar (KCLE), 106 km from the middle of the area, began a volume at 17:21 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
30%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

16 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Aug 1, 1:19 PM EDTSevere Thunderstorm WarningCLELucas, Ottawa, Wood56 min
Aug 1, 1:32 PM EDTSevere Thunderstorm WarningCLEErie, Sandusky58 min
Aug 1, 1:42 PM EDTSevere Thunderstorm WarningCLEWood63 min
Aug 1, 1:53 PM EDTTornado WarningCLESandusky, Wood37 min
Aug 1, 2:10 PM EDTSevere Thunderstorm WarningCLELorain54 min
Aug 1, 2:16 PM EDTSevere Thunderstorm WarningCLEMedina, Portage, Summit, Wayne44 min
Aug 1, 2:24 PM EDTSevere Thunderstorm WarningCLESeneca66 min
Aug 1, 2:31 PM EDTSevere Thunderstorm WarningCLEMedina44 min
Aug 1, 2:42 PM EDTSevere Thunderstorm WarningIWXFulton46 min
Aug 1, 2:57 PM EDTSevere Thunderstorm WarningCLEMedina, Stark, Summit, Wayne63 min
Aug 1, 3:09 PM EDTSevere Thunderstorm WarningCLEWyandot66 min
Aug 1, 4:04 PM EDTSevere Thunderstorm WarningCLEMarion56 min
Aug 1, 4:15 PM EDTSevere Thunderstorm WarningCLEWyandot30 min
Aug 1, 5:15 PM EDTSevere Thunderstorm WarningILNDelaware, Union45 min
Aug 1, 5:35 PM EDTSevere Thunderstorm WarningIWXHenry, Putnam29 min
Aug 1, 5:38 PM EDTSevere Thunderstorm WarningILNDelaware, Franklin, Madison, Union52 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

Detroit, MI (KDTX), launched 12:00Z, 5.3 hours before the alert went out and 161 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-pSkew-T log-p diagram, Detroit, MI at 12:00Z on 2011-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2432 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Detroit, MI at 12:00Z on 2011-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 118 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
2432 J/kg
Mixed-layer CIN
-38 J/kg
Mixed-layer LCL
864 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
118 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
1.0
Supercell composite
7.2

Open this sounding in Storm Lab

The text

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

006 
WWUS20 KWNS 011719
SEL0
SPC WW 011719
OHZ000-WVZ000-LEZ000-020100-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 710
NWS STORM PREDICTION CENTER NORMAN OK
120 PM EDT MON AUG 1 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

       NORTHERN AND CENTRAL OHIO
       FAR NORTHERN WEST VIRGINIA
       LAKE ERIE

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 120 PM UNTIL 900
PM EDT.

HAIL TO 2 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 60
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 60 MILES WEST
SOUTHWEST OF TOLEDO OHIO TO 25 MILES SOUTH SOUTHEAST OF
YOUNGSTOWN OHIO.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).

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 709...

DISCUSSION...TSTM WILL LIKELY CONTINUE TO INTENSIFY THIS AFTERNOON
AHEAD OF SURFACE FRONT WHERE AIR MASS HAS BECOME STRONGLY UNSTABLE
WITH MLCAPE OF 3000 J/KG.  THE PRESENCE OF STEEP MIDLEVEL LAPSE
RATES AND 40 KT OF DEEP NWLY SHEAR /REF. 12Z DTX SOUNDING/ WILL
PROMOTE SUPERCELLS CAPABLE OF LARGE HAIL AND DAMAGING WINDS WITH
ACTIVITY SPREADING SWD/SEWD ACROSS WATCH AREA.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 33030.


...MEAD

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 1, 3:47 AM EDTMesoscale DiscussionSPCBay, Clinton, Genesee, Gladwin, Gratiot, Ingham and 12 more58 min
Aug 1, 8:01 AM EDTMesoscale DiscussionSPCMonroe89 min
Aug 1, 1:06 PM EDTMesoscale DiscussionSPCBranch, Calhoun, Eaton, Hillsdale, Jackson, Lenawee and 2 more24 min
Aug 1, 3:39 PM EDTMesoscale DiscussionSPCAllen, Ashland, Ashtabula, Auglaize, Belmont, Carroll and 64 more66 min
Aug 1, 3:22 PM EDTMesoscale DiscussionSPCBerkeley, Grant, Hampshire, Hardy, Jefferson, Mineral and 2 more83 min

Nearby

Severe Thunderstorm Watches in Ohio, 2011Severe Thunderstorm Watches in West Virginia, 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.