Alert archive / Oklahoma / Mesoscale Discussions in 2012

Mesoscale Discussion 2209

December 25, 201213 counties in Oklahoma; Wichita County, Wilbarger County, Texas

The Storm Prediction Center issued this mesoscale discussion at Dec 25, 2012, 11:02 AM CST for 13 counties in Oklahoma; Wichita County, Wilbarger County, Texas. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Dec 25, 2012, 11:02 AM CST (17:02 UTC)
Expired
Dec 25, 2012, 3:00 PM CST
In force
4 hr
Issued by
the Storm Prediction Center

Counties Caddo County, OK, Carter County, OK, Comanche County, OK, Cotton County, OK, Garvin County, OK, Grady County, OK, Jackson County, OK, Jefferson County, OK, Kiowa County, OK, Murray County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK, Wichita County, TX, Wilbarger County, TX

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 5.0 hours before the alert went out and 106 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 2012-12-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2012-12-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 312 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
524 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
312 m²/s²
0-3 km storm-relative helicity
223 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.

599 
ACUS11 KWNS 251702
SWOMCD
SPC MCD 251702 
OKZ000-TXZ000-252100-

MESOSCALE DISCUSSION 2209
NWS STORM PREDICTION CENTER NORMAN OK
1102 AM CST TUE DEC 25 2012

AREAS AFFECTED...SWRN/W-CNTRL/S-CNTRL OK...WRN NORTH TX

CONCERNING...BLIZZARD 

VALID 251702Z - 252100Z

SUMMARY...BLIZZARD CONDITIONS ARE DEVELOPING ACROSS
SWRN/W-CNTRL/S-CNTRL OK...AND WILL CONTINUE THROUGH AROUND 22-23Z.
NLY WINDS OF 25-35 MPH WITH FREQUENT GUSTS OF 40-45 MPH WILL COMBINE
WITH SNOWFALL RATES OF 1-1.5 IN/HR TO GENERATE NEAR-ZERO
VISIBILITIES AND WHITEOUT CONDITIONS.

DISCUSSION...LATEST SFC MESOANALYSIS AND OK MESONET OBSERVATIONS
SUGGEST THAT THE TIGHT SFC PRESSURE GRADIENT AND STRENGTH OF THE
LOW-LEVEL FLOW ARE TRENDING STRONGER THAN THE BULK OF SHORT-RANGE
MODEL GUIDANCE. WITH CONTINUED DEEPENING OF AN E-TX SFC
LOW...LOW-LEVEL FLOW WILL FURTHER STRENGTHEN. THIS IS SUGGESTED BY
RAPID-REFRESH FORECAST SOUNDINGS...WHICH DEPICT 0-1-KM MEAN FLOW
INCREASING TO ABOVE 40 KT DURING THE NEXT FEW HOURS. INCREASING
DIFFERENTIAL COLD ADVECTION AND DECREASING STATIC STABILITY IN THE
LOWEST KILOMETER AGL WILL ALLOW THIS FLOW TO BE MANIFESTED AT THE
SFC AS SUSTAINED WINDS OF 25-35 MPH WITH FREQUENT GUSTS OF 40-45
MPH. THESE WINDS WILL COMBINE WITH SNOWFALL RATES OF 1-1.5
IN/HR...AS ADDRESSED IN MESOSCALE DISCUSSION NUMBER 2208...TO
GENERATE WHITEOUT CONDITIONS WITH NEAR-ZERO VISIBILITIES AND
WIDESPREAD BLIZZARD CONDITIONS. QUARTER-MILE VISIBILITIES HAVE
ALREADY BEEN OBSERVED AT CLINTON OK WITH 30 KT SUSTAINED WINDS
GUSTING TO 38 KT...AND SIMILAR CONDITIONS WILL SPREAD ACROSS THE
AREA THROUGH THE AFTERNOON. THESE WINDS/SNOW SHOULD CONTINUE THROUGH
AROUND 22-23Z. ACCORDINGLY...THIS BLIZZARD MESOSCALE DISCUSSION HAS
BEEN ISSUED UPON COORDINATION WITH THE NORMAN OK WEATHER FORECAST
OFFICE.

..COHEN.. 12/25/2012

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

ATTN...WFO...FWD...OUN...

LAT...LON   33889904 34149937 34999954 35439934 35559879 35289822
            34919732 34609667 34199670 34079680 33979727 33829832
            33889904

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 25, 2:32 AM CSTMesoscale DiscussionSPCBlaine, Caddo, Canadian, Cleveland, Comanche, Creek and 21 more4 hr
Dec 25, 9:31 AM CSTMesoscale DiscussionSPCCaddo, Canadian, Carter, Comanche, Cotton, Garvin and 9 more5 hr
Dec 25, 12:11 PM CSTMesoscale DiscussionSPCAtoka, Bryan, Choctaw, Coal, Haskell, Johnston and 6 more5 hr
Dec 25, 2:50 PM CSTMesoscale DiscussionSPCBeckham, Caddo, Comanche, Cotton, Custer, Greer and 6 more4 hr
Dec 25, 1:01 AM CSTMesoscale DiscussionSPCAnderson, Angelina, Austin, Bell, Bosque, Brazos and 37 more59 min
Dec 25, 1:37 AM CSTSevere Thunderstorm WatchSPCAnderson, Angelina, Bell, Bosque, Brazos, Burleson and 36 more7 hr
Dec 25, 5:56 AM CSTMesoscale DiscussionSPCAnderson, Angelina, Bell, Bosque, Brazos, Burleson and 38 more94 min
Dec 25, 7:00 AM CSTMesoscale DiscussionSPCBrazoria, Chambers, Galveston, Hardin, Harris, Jasper and 9 more60 min
Dec 25, 8:46 AM CSTMesoscale DiscussionSPCAngelina, Brazoria, Chambers, Cherokee, Fort Bend, Galveston and 26 more59 min
Dec 25, 9:02 AM CSTSevere Thunderstorm WatchSPCAngelina, Cherokee, Gregg, Harrison, Marion, Nacogdoches and 6 more7 hr
Dec 25, 9:17 AM CSTTornado WatchSPCAustin, Brazoria, Chambers, Fort Bend, Galveston, Grimes and 16 more8 hr
Dec 25, 12:19 PM CSTMesoscale DiscussionSPCChambers, Galveston, Hardin, Jasper, Jefferson, Newton and 1 more71 min
Dec 25, 1:00 PM CSTMesoscale DiscussionSPCBowie, Camp, Cass, Collin, Dallas, Delta and 16 more5 hr

Nearby

Mesoscale Discussions in Oklahoma, 2012Mesoscale Discussions in Texas, 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.