Alert archive / Oklahoma / Mesoscale Discussions in 2011

Mesoscale Discussion 98

February 8, 201118 counties in Oklahoma; 4 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Feb 8, 2011, 10:45 PM CST for 18 counties in Oklahoma; 4 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Feb 8, 2011, 10:45 PM CST (04:45 UTC)
Expired
Feb 9, 2011, 1:45 AM CST
In force
3 hr
Issued by
the Storm Prediction Center
All 22 counties

Beckham County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Comanche County, OK, Custer County, OK, Dewey County, OK, Garfield County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Kingfisher County, OK, Kiowa County, OK, Logan County, OK, Major County, OK, Oklahoma County, OK, Roger Mills County, OK, Washita County, OK, Childress County, TX, Collingsworth County, TX, Donley County, TX, Wheeler County, TX

The radar

The Altus AFB radar (KFDR), 111 km from the middle of the area, began a volume at 04:51 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, 4.8 hours before the alert went out and 168 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 00:00Z on 2011-02-09Temperature 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 00:00Z on 2011-02-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 342 square meters per square second.1939587897117136156Sfc1 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
1114 m above ground
0-6 km bulk shear
103 kt
0-1 km storm-relative helicity
342 m²/s²
0-3 km storm-relative helicity
753 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.

740 
ACUS11 KWNS 090445
SWOMCD
SPC MCD 090445 
OKZ000-TXZ000-090745-

MESOSCALE DISCUSSION 0098
NWS STORM PREDICTION CENTER NORMAN OK
1045 PM CST TUE FEB 08 2011

AREAS AFFECTED...THE TX PANHANDLE AND WESTERN/CNTRL OKLAHOMA

CONCERNING...HEAVY SNOW 

VALID 090445Z - 090745Z

MODELS SUGGEST THAT FRONTOGENETIC FORCING ACROSS THE SOUTH CENTRAL
PLAINS WILL TEND TO WEAKEN OVERNIGHT...AND THE POTENTIAL FOCUS FOR
SUSTAINED HEAVY SNOW BANDS IS NOT CLEAR.  HOWEVER...GUIDANCE DOES
APPEAR SIMILAR IN DEVELOPING/MAINTAINING AN AREA OF STRONG UPWARD
VERTICAL MOTION IN THE 700 TO 500 MB LAYER ACROSS THE WEST CENTRAL
OKLAHOMA DURING THE 06-09Z TIME FRAME.  THIS COINCIDES WITH THE
MIXED PHASE LAYER FAVORABLE FOR LARGE DENDRITIC ICE CRYSTAL
GROWTH...WHICH PROBABLY WILL PROMOTE HEAVY SNOW RATES IN EXCESS OF 1
INCH PER HOUR...PERHAPS UP TO 2 INCHES PER HOUR...PARTICULARLY AS
HIGHER PRECIPITABLE WATER CONTINUES TO ADVECT NORTHWARD INTO THE
REGION.  HEAVIEST SNOW RATES MAY NOT IMPACT THE OKLAHOMA CITY
METROPOLITAN AREA...ESPECIALLY DOWNTOWN AND SOUTHEASTERN
SECTIONS...UNTIL CLOSER TO 09Z.

..KERR.. 02/09/2011

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

ATTN...WFO...OUN...LUB...AMA...

LAT...LON   35500050 36279953 36419773 35769704 35019798 34549865
            34419951 34640176 35500050

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 8, 7:16 PM CSTMesoscale DiscussionSPCBeckham, Blaine, Custer, Dewey, Ellis, Greer and 4 more3 hr
Feb 9, 2:33 AM CSTMesoscale DiscussionSPCBryan, Choctaw4 hr
Feb 9, 3:29 AM CSTMesoscale DiscussionSPCAdair, Atoka, Canadian, Cherokee, Cleveland, Coal and 36 more6 hr
Feb 9, 10:03 AM CSTMesoscale DiscussionSPCChoctaw, Latimer, LeFlore, McCurtain, Pushmataha6 hr

Nearby

Mesoscale Discussions in Oklahoma, 2011Mesoscale Discussions in Texas, 2011Every mesoscale discussion in 2011

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.