Alert archive / Ohio / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 212, NWS Wilmington, OH

August 11, 2001Clermont County, Ohio

NWS Wilmington, OH issued this severe thunderstorm warning at Aug 11, 2001, 8:57 PM EDT for Clermont County, Ohio. It was in force for 48 min. 1 report 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, 2001, 8:57 PM EDT (00:57 UTC)
Expired: Aug 11, 2001, 9:45 PM EDT
In force: 48 min
Issued by: NWS Wilmington, OH
Area: Whole counties

County Clermont County, OH

The radar

The Cincinnati radar (KILN), 50 km from the middle of the area, began a volume at 00:57 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, 9:10 PM EDT	Thunderstorm Wind 50 E	Countywide, OH	Trees knocked down in several locations across the county.

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

Cncnati-Daytn, OH (KILN), launched 00:00Z, 1.0 hours before the alert went out and 52 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1223 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 909 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 27 m²/s²
0-3 km storm-relative helicity: 89 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 3.1

Open this sounding in Storm Lab

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 Wilmington, OH wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 11, 2:40 PM EDT, 6 hours 17 minutes earlier.

Area forecast discussion, Aug 11, 2:40 PM EDT, 6 hours 17 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
240 PM EDT SAT AUG 11 2001

SFC WAVE HAS MOVED INTO SE INDIANA LATE THIS AFTN...WITH FRONTAL
BNDRY NOW APPARENTLY NORTH OF CVG.  L-M 70S DWPTS WERE POOLING ALONG
AND SOUTH OF THE BNDRY...LIKELY SETTING THE STAGE FOR SOME EFFICIENT
RAINERS OVER FAR SOUTHERN (NORTHERN KY) PARTS OF THE FORECAST AREA.
DECENT LLVL CONVERGENCE PROGGED ACRS THE ENTIRE AREA OVERNIGHT AS
WAVE MOVES ACRS...AND PLAN ON CARRYING POPS ALL ZONES.  WL HIT POPS
HARDEST OVER THE SOUTH WHERE PCPN EFFICIENCY THE GREATEST...AND DUE
TO SLOW MOVEMENT WL MENTION +RA.  BASICALLY PLANNING A 20% NORTH TO
60% FAR SOUTH BREAKDOWN.  FWC TEMPS HV GOTTEN A LOT BETTER...BUT
STILL WL LIKELY RAISE A DEG OR SO.

GUID IN PRETTY GD AGREEMENT THAT SFC WAVE/UPPER FORCING WL SHIFT
EAST OF THE CWFA BY LATE AFTN SUN...FOLLOWED BY A DEEP DRYING OF THE
ATMOS.  WL CARRY MORNING CHC POPS SOUTHWEST...AND THRU ERLY AFTN IN
THE EAST...AND ADVERTISE SOME MANNER OF CLEARING ALL ZONES.  WITH
FAIRLY WIDESPRD CLDS ERLY...AND CAA KICKING IN LATE...HV UNDERCUT
THE FWC TEMPS A DEG OR 2.

FLOW CONTS TO AMPLIFY THRU THE SHORT RANGE...WITH THE NEW GUID INDC
A WEAK BNDRY WL MV ACRS THE RGN ON MONDAY.  MSTR LKS SPARSE
HWVR...AND DO NOT PLAN ON INTRODUCING POPS.

.ILN...NONE.

JOHNSTONE

In the hours before

Local storm report, Aug 11, 8:32 PM EDT, 25 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE WILMINGTON, OH
832 PM EDT SAT AUG 11 2001

TIME(EDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0810 PM    SOUTHERN PART OF COUNTY   OH   WIND DAMAGE
08/11/01   WARREN                         TREES DOWN
                                          REPORTED BY
                                          LAW ENFORCEMENT
                                          OFFICIALS

WILKINSON

The office that day

Everything else NWS Wilmington, OH issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 11, 11:05 PM EDT	Flash Flood Warning	ILN	Mason	85 min
Aug 12, 12:25 AM EDT	Flash Flood Warning	ILN	Mason	2 hr
Aug 12, 12:54 AM EDT	Flash Flood Warning	ILN	Lewis	2 hr

Nearby

Severe Thunderstorm Warnings in Ohio, 2001 Every severe thunderstorm warning in 2001

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.