Alert archive / Ohio / Mesoscale Discussions in 2008

Mesoscale Discussion 39

January 9, 20086 counties in Kentucky; 25 counties in Ohio; Mason County, West Virginia

The Storm Prediction Center issued this mesoscale discussion at Jan 9, 2008, 12:26 AM EST for 6 counties in Kentucky; 25 counties in Ohio; Mason County, West Virginia. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued: Jan 9, 2008, 12:26 AM EST (05:26 UTC)
Expired: Jan 9, 2008, 2:00 AM EST
In force: 94 min
Issued by: the Storm Prediction Center

All 32 counties

Boyd County, KY, Carter County, KY, Fleming County, KY, Greenup County, KY, Lewis County, KY, Rowan County, KY, Athens County, OH, Carroll County, OH, Coshocton County, OH, Fairfield County, OH, Gallia County, OH, Guernsey County, OH, Hocking County, OH, Holmes County, OH, Jackson County, OH, Knox County, OH, Lawrence County, OH, Licking County, OH, Meigs County, OH, Morgan County, OH, Morrow County, OH, Muskingum County, OH, Noble County, OH, Perry County, OH, Pickaway County, OH, Pike County, OH, Ross County, OH, Scioto County, OH, Tuscarawas County, OH, Vinton County, OH, Wayne County, OH, Mason County, WV

The radar

The Cincinnati radar (KILN), 125 km from the middle of the area, began a volume at 05:28 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.

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 13Jan 9, 12:55 AM EST

The nearest sounding before it

Cncnati-Daytn, OH (KILN), launched 00:00Z, 5.4 hours before the alert went out and 123 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: 63 J/kg
Mixed-layer CIN: -37 J/kg
Mixed-layer LCL: 1018 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 428 m²/s²
0-3 km storm-relative helicity: 454 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 090526
SWOMCD
SPC MCD 090526 
OHZ000-WVZ000-KYZ000-090700-

MESOSCALE DISCUSSION 0039
NWS STORM PREDICTION CENTER NORMAN OK
1126 PM CST TUE JAN 08 2008

AREAS AFFECTED...NERN KY THROUGH CNTRL AND ERN OH AND EXTREME WRN WV

CONCERNING...TORNADO WATCH 12...

VALID 090526Z - 090700Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 12 CONTINUES.

THREAT FOR MAINLY ISOLATED DAMAGING WIND AND POSSIBLY A TORNADO OR
TWO WILL PERSIST NEXT FEW HOURS MAINLY FROM NERN KY THROUGH E CNTRL
OH. SOME POTENTIAL EXISTS FOR ACTIVITY TO REMAIN CAPABLE OF ISOLATED
DAMAGING WIND GUSTS AS CONVECTION BEGINS TO MOVE EAST OF WW 12 BY
06Z. TRENDS ARE BEING MONITORED FOR ANOTHER WW DOWNSTREAM OF WW 12
THAT WOULD INCLUDE PARTS OF ERN OH AND POSSIBLY EXTREME WRN WV. 

SEVERAL FORCED LINE SEGMENTS OF LOW TOPPED CONVECTION WITH LITTLE OR
NO LIGHTNING CONTINUE FROM S CNTRL THROUGH CNTRL OH WITHIN ZONE OF
DPVA AND PRESSURE FALLS ATTENDING AN ENEWD EJECTING NEGATIVELY
TILTED SHORTWAVE TROUGH. DESPITE A VERY MARGINAL THERMODYNAMIC
ENVIRONMENT WITH MUCAPE AOB 300 J/KG...THE STRONG 70+ KT LOW LEVEL
JET IS CONTRIBUTING TO POTENTIAL FOR DOWNWARD MOMENTUM TRANSPORT
WITHIN THE HEAVIER RAIN CORES OF THE LINE SEGMENTS. DEWPOINTS DROP
INTO THE 40S AND INSTABILITY IS EVEN MORE MARGINAL ACROSS ERN OH TO
THE EAST OF WW 12. HOWEVER...THIS DRYER BOUNDARY LAYER MAY ENHANCE
THE POTENTIAL FOR DOWNWARD MIXING AND EVAPORATIVE COOLING PROVIDED
THERE IS ENOUGH INSTABILITY AND FORCING TO MAINTAIN THE CONVECTION.

..DIAL.. 01/09/2008

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...PBZ...RLX...CLE...JKL...ILN...

40568102 38838177 38268263 38148387 38928341 40038294
40568289 40888202

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 8, 9:01 PM EST	Mesoscale Discussion	SPC	Anderson, Boone, Bracken, Breckinridge, Bullitt, Campbell and 21 more	89 min
Jan 8, 10:07 PM EST	Tornado Watch	SPC	Boone, Bourbon, Bracken, Campbell, Carroll, Franklin and 15 more	4 hr
Jan 9, 12:53 AM EST	Severe Thunderstorm Watch	SPC	Boyd, Carter, Greenup, Lawrence	3 hr
Jan 8, 11:30 PM EST	Mesoscale Discussion	SPC	Ashland, Crawford, Erie, Holmes, Huron, Medina and 8 more	60 min

Nearby

Mesoscale Discussions in Ohio, 2008 Mesoscale Discussions in Kentucky, 2008 Mesoscale Discussions in West Virginia, 2008 Every mesoscale discussion in 2008

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.