Alert archive / Oklahoma / Mesoscale Discussions in 2012

Mesoscale Discussion 236

March 8, 201220 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at Mar 8, 2012, 2:54 PM CST for 20 counties in Oklahoma. It was in force for 66 min.

The area

The outline as issued.

The facts

Issued
Mar 8, 2012, 2:54 PM CST (20:54 UTC)
Expired
Mar 8, 2012, 4:00 PM CST
In force
66 min
Issued by
the Storm Prediction Center

Counties Atoka County, OK, Bryan County, OK, Carter County, OK, Choctaw County, OK, Coal County, OK, Cotton County, OK, Garvin County, OK, Grady County, OK, Hughes County, OK, Jefferson County, OK, Johnston County, OK, Love County, OK, Marshall County, OK, McClain County, OK, McCurtain County, OK, Murray County, OK, Pittsburg County, OK, Pontotoc County, OK, Pushmataha County, OK, Stephens County, OK

The radar

The Norman radar (KTLX), 126 km from the middle of the area, began a volume at 20:55 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

Norman, OK (KOUN), launched 12:00Z, 8.9 hours before the alert went out and 124 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, Norman, OK at 12:00Z on 2012-03-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 9 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 12:00Z on 2012-03-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 195 square meters per square second.1939587897Sfc1 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
9 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
405 m above ground
0-6 km bulk shear
68 kt
0-1 km storm-relative helicity
195 m²/s²
0-3 km storm-relative helicity
205 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.4

Open this sounding in Storm Lab

The text

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

811 
ACUS11 KWNS 082055
SWOMCD
SPC MCD 082054
OKZ000-TXZ000-082200-

MESOSCALE DISCUSSION 0236
NWS STORM PREDICTION CENTER NORMAN OK
0254 PM CST THU MAR 08 2012

AREAS AFFECTED...S-CNTRL AND SERN OK

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 082054Z - 082200Z

AN ISOLATED/MARGINAL THREAT FOR SVR HAIL WILL EXIST OVER PORTIONS OF
SRN OK. A WW IS NOT ANTICIPATED.

2030Z RADAR LOOP SHOWS INTENSIFICATION OF ISOLATED ELEVATED TSTMS
OVER SRN OK. THIS IS OCCURRING WITHIN A BROAD WARM ADVECTION
ZONE...ROOTED NEAR 1.5-2 KM AGL AND AIDED BY 30 KTS OF SWLY FLOW
/PER REGIONAL VWP DATA/. WITH STEEP MIDLEVEL LAPSE RATES IN PLACE /7
DEG C PER KM/ AND EFFECTIVE SHEAR VALUES NEAR 50 KTS...AN ISOLATED
THREAT FOR SVR HAIL WILL ACCOMPANY ORGANIZED/STRONGER UPDRAFTS.
HOWEVER...THIS THREAT APPEARS TO BE RELATIVELY CONFINED TO AREAS
ALONG AND IMMEDIATELY N OF THE RED RIVER...WHERE MIDLEVEL THERMAL
GRADIENT AND FOCUSED AREA OF ISENTROPIC ASCENT APPEAR TO BE
MAXIMIZED /PER 20Z RUC OBJECTIVE ANALYSIS/. ADDITIONALLY...ELEVATED
INSTABILITY BECOMES INCREASINGLY MORE MARGINAL WITH NWD
PROGRESSION...WITH TSTMS RAPIDLY MOVING N-NEWD INTO AN ENVIRONMENT
LESS FAVORABLE FOR LARGE HAIL PRODUCTION. GIVEN THESE
FACTORS...COVERAGE AND INTENSITY APPEAR TOO MARGINAL TO WARRANT
ISSUANCE OF A WW ATTM.

..ROGERS.. 03/08/2012

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

ATTN...WFO...SHV...TSA...FWD...OUN...

LAT...LON   33909508 33799621 33889742 34039809 34259845 34799829
            35119778 35149698 35069632 35049589 34779515 34429460
            34039464 33909508

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 7, 7:36 PM CSTMesoscale DiscussionSPCAlfalfa, Beckham, Blaine, Caddo, Canadian, Custer and 22 more84 min
Mar 8, 10:19 AM CSTMesoscale DiscussionSPCBryan, Choctaw, McCurtain, Pushmataha56 min

Nearby

Mesoscale Discussions in Oklahoma, 2012Every 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.