Alert archive / Ohio / Mesoscale Discussions in 2021

Mesoscale Discussion 1869

October 16, 202111 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at Oct 16, 2021, 2:16 AM EDT for 11 counties in Ohio. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued: Oct 16, 2021, 2:16 AM EDT (06:16 UTC)
Expired: Oct 16, 2021, 3:45 AM EDT
In force: 89 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 20%

Counties Coshocton County, OH, Fairfield County, OH, Guernsey County, OH, Harrison County, OH, Hocking County, OH, Morgan County, OH, Muskingum County, OH, Noble County, OH, Perry County, OH, Pickaway County, OH, Tuscarawas County, OH

The radar

The Cincinnati radar (KILN), 153 km from the middle of the area, began a volume at 06:20 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

Cncnati-Daytn, OH (KILN), launched 00:00Z, 6.3 hours before the alert went out and 151 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: 8 J/kg
Mixed-layer CIN: -85 J/kg
Mixed-layer LCL: 841 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 37 m²/s²
0-3 km storm-relative helicity: 91 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

517 
ACUS11 KWNS 160617
SWOMCD
SPC MCD 160616 COR
OHZ000-160745-

Mesoscale Discussion 1869
NWS Storm Prediction Center Norman OK
0116 AM CDT Sat Oct 16 2021

Areas affected...portions of southeast Ohio

Concerning...Severe potential...Watch unlikely 

Valid 160616Z - 160745Z

CORRECTED FOR GRAPHIC ERROR

Probability of Watch Issuance...20 percent

SUMMARY...A weak, brief tornado or two may occur over parts of
southern Ohio over the next couple of hours.

DISCUSSION...A persistent supercell near the southeastward-advancing
cold front has produced several moderate mesos with radar-indicted
tornado debris signatures in Highland and Ross counties over the
past hour. This cell appears to be located near a meso low and/or
MCV, which is likely supporting locally enhanced SRH. Furthermore,
this cell is within an area of relatively stronger low-level
instability and surface vorticity as noted in latest mesoanalysis.
Downstream surface dewpoints are in the low/mid 60s with locally
backed surface winds. This should continue to support at least low
potential for sporadic re-intensification of ongoing convection and
some threat for weak/brief spin-ups to occur over a relatively small
area. The broader environment appears unlikely to support a more
widespread threat or increasing convective coverage. While a tornado
watch is not expected at this time, trends will continue to be
monitored.

..Leitman/Edwards.. 10/16/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...PBZ...RLX...ILN...

LAT...LON   39958275 40338190 40468145 40438113 40228102 39928109
            39698142 39508195 39368245 39398280 39448300 39628312
            39778301 39958275

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 15, 10:44 PM EDT	Mesoscale Discussion	SPC	Adams, Brown, Clermont, Clinton, Fayette, Highland and 6 more	2 hr

Nearby

Mesoscale Discussions in Ohio, 2021 Every mesoscale discussion in 2021

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.