Alert archive / Oklahoma / Mesoscale Discussions in 2012

Mesoscale Discussion 2204

December 25, 201227 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at Dec 25, 2012, 2:32 AM CST for 27 counties in Oklahoma. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: Dec 25, 2012, 2:32 AM CST (08:32 UTC)
Expired: Dec 25, 2012, 6:30 AM CST
In force: 4 hr
Issued by: the Storm Prediction Center

All 27 counties

Blaine County, OK, Caddo County, OK, Canadian County, OK, Cleveland County, OK, Comanche County, OK, Creek County, OK, Custer County, OK, Dewey County, OK, Garfield County, OK, Garvin County, OK, Grady County, OK, Kingfisher County, OK, Kiowa County, OK, Lincoln County, OK, Logan County, OK, Major County, OK, McClain County, OK, Noble County, OK, Okfuskee County, OK, Oklahoma County, OK, Pawnee County, OK, Payne County, OK, Pontotoc County, OK, Pottawatomie County, OK, Seminole County, OK, Stephens County, OK, Washita County, OK

The radar

The Norman radar (KTLX), 49 km from the middle of the area, began a volume at 08:35 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 00:00Z, 8.5 hours before the alert went out and 41 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2115 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 265 m²/s²
0-3 km storm-relative helicity: 368 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.

870 
ACUS11 KWNS 250833
SWOMCD
SPC MCD 250832
OKZ000-251230-

MESOSCALE DISCUSSION 2204
NWS STORM PREDICTION CENTER NORMAN OK
0232 AM CST TUE DEC 25 2012

AREAS AFFECTED...PORTIONS OF WESTERN AND CENTRAL OKLAHOMA

CONCERNING...WINTER MIXED PRECIPITATION

VALID 250832Z - 251230Z

SUMMARY...SNOW...SLEET AND FREEZING RAIN WILL IMPACTS PARTS OF
WESTERN AND CENTRAL OK THE NEXT FEW HOURS. WHILE PRECIPITATION IS
EXPECTED TO BE SCATTERED AND LIGHT...HAZARDOUS TRAVEL CONDITIONS CAN
DEVELOP WITH ONLY SMALL ICE ACCUMULATION.

DISCUSSION...LOW LEVEL MOISTURE WAS BEING TRANSPORTED INTO THE AREA
VIA ELY LOW LEVEL FLOW /AS EVIDENT IN KTLX 88-D VWP DATA/. AN
INITIAL SHORTWAVE IMPULSE MOVING ACROSS CENTRAL OKLAHOMA EARLY THIS
MORNING AHEAD OF THE MAIN UPPER TROUGH WAS PROVIDING FORCING FOR
ASCENT AND RESULTING IN LIGHT WINTRY MIX PRECIP TYPES. FREEZING
RAIN/SLEET AND SNOW RATES WILL BE LOW THE NEXT FEW HOURS AS MIDLEVEL
MOISTURE ONLY SLOWLY INCREASES. HOWEVER...LIGHT ACCUMULATIONS OF
SLEET AND FREEZING RAIN ON ROADWAYS WILL LEAD TO HAZARDOUS TRAVEL
CONDITIONS. AS MID LEVEL TEMPERATURES COOL AFTER SUNRISE...SLEET MAY
MIX WITH SNOW FOR A BRIEF PERIOD BEFORE A TRANSITION TO ALL SNOW
OCCURS AND PRECIPITATION BECOMES HEAVIER.

..LEITMAN.. 12/25/2012

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

ATTN...WFO...TSA...OUN...

LAT...LON   34689926 35049947 35699940 36289885 36409816 36439732
            36479686 36349657 35899631 35119626 34819638 34569688
            34509742 34459799 34559871 34689926

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 25, 9:31 AM CST	Mesoscale Discussion	SPC	Caddo, Canadian, Carter, Comanche, Cotton, Garvin and 9 more	5 hr
Dec 25, 11:02 AM CST	Mesoscale Discussion	SPC	Caddo, Carter, Comanche, Cotton, Garvin, Grady and 7 more	4 hr
Dec 25, 12:11 PM CST	Mesoscale Discussion	SPC	Atoka, Bryan, Choctaw, Coal, Haskell, Johnston and 6 more	5 hr
Dec 25, 2:50 PM CST	Mesoscale Discussion	SPC	Beckham, Caddo, Comanche, Cotton, Custer, Greer and 6 more	4 hr

Nearby

Mesoscale Discussions in Oklahoma, 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.