Alert archive / Ohio / Mesoscale Discussions in 2012

Mesoscale Discussion 252

March 12, 201212 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at Mar 12, 2012, 11:09 PM EDT for 12 counties in Ohio. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: Mar 12, 2012, 11:09 PM EDT (03:09 UTC)
Expired: Mar 13, 2012, 12:45 AM EDT
In force: 96 min
Issued by: the Storm Prediction Center

Counties Defiance County, OH, Erie County, OH, Fulton County, OH, Hancock County, OH, Henry County, OH, Lucas County, OH, Ottawa County, OH, Paulding County, OH, Putnam County, OH, Sandusky County, OH, Seneca County, OH, Wood County, OH

The radar

The Detroit radar (KDTX), 155 km from the middle of the area, began a volume at 03:09 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 nearest sounding before it

Detroit, MI (KDTX), launched 00:00Z, 3.2 hours before the alert went out and 158 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: 6 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 519 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 434 m²/s²
0-3 km storm-relative helicity: 589 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

533 
ACUS11 KWNS 130309
SWOMCD
SPC MCD 130309 
OHZ000-MIZ000-INZ000-130445-

MESOSCALE DISCUSSION 0252
NWS STORM PREDICTION CENTER NORMAN OK
1009 PM CDT MON MAR 12 2012

AREAS AFFECTED...PARTS OF NE IND...NRN OH

CONCERNING...TORNADO WATCH 74...

VALID 130309Z - 130445Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 74 CONTINUES.

BUT THE THREAT IS CONTINUING TO GRADUALLY DIMINISH.

THE COLD FRONT HAS ADVANCED THROUGH MUCH OF LOWER MICHIGAN...AND
WILL LIKELY CONTINUE A STEADY EASTWARD PROGRESSION TOWARD THE LOWER
GREAT LAKES REGION...WHILE MORE SLOWLY MOVING SOUTHWARD TOWARD THE
OHIO VALLEY.  FORCING FOR UPWARD VERTICAL MOTION WITHIN A NARROW
PRE-FRONTAL INSTABILITY AXIS IS MAINTAINING A LINE OF THUNDERSTORMS
NEAR THE SOUTHERN MICHIGAN/OHIO/INDIANA BORDER AREA.  THROUGH
04-06Z...THIS ACTIVITY IS EXPECTED TO SPREAD ACROSS TOLEDO AND
ADJACENT AREAS OF NORTHWEST OHIO...INTO THE WESTERN LAKE
ERIE...BEFORE CONTINUING TO WEAKEN AND DISSIPATE OVERNIGHT. 
ALTHOUGH THE SEVERE WEATHER THREAT HAS ALREADY DIMINISHED
CONSIDERABLY...RUC GUIDANCE SUGGESTS THAT CONVECTION GENERALLY
COINCIDES WITH A 50+ KT WEST SOUTHWESTERLY 850 MB JET CORE...AND IT
MAY NOT BE OUT OF THE QUESTION THAT IT COULD AID THE DOWNWARD
TRANSPORT OF HIGHER MOMENTUM AIR TO THE SURFACE...SUPPORTING AT
LEAST SOME LINGERING RISK FOR POTENTIALLY DAMAGING SURFACE GUSTS.

..KERR.. 03/13/2012

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

ATTN...WFO...CLE...DTX...IWX...

LAT...LON   41008522 41698406 41788318 41738277 41518233 41058307
            40888454 41008522

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 12, 8:43 PM EDT	Mesoscale Discussion	SPC	Defiance, Fulton, Henry, Lucas, Ottawa, Williams and 1 more	92 min

Nearby

Mesoscale Discussions in Ohio, 2012 Every mesoscale discussion 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.