Alert archive / Oklahoma / Mesoscale Discussions in 2011

Mesoscale Discussion 38

January 19, 201125 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at Jan 19, 2011, 10:50 PM CST for 25 counties in Oklahoma. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Jan 19, 2011, 10:50 PM CST (04:50 UTC)
Expired
Jan 20, 2011, 3:15 AM CST
In force
4 hr
Issued by
the Storm Prediction Center
All 25 counties

Blaine County, OK, Canadian County, OK, Cleveland County, OK, Creek County, OK, Custer County, OK, Dewey County, OK, Garfield County, OK, Kingfisher County, OK, Lincoln County, OK, Logan County, OK, Major County, OK, Mayes County, OK, Noble County, OK, Nowata County, OK, Okfuskee County, OK, Oklahoma County, OK, Okmulgee County, OK, Osage County, OK, Pawnee County, OK, Payne County, OK, Rogers County, OK, Tulsa County, OK, Wagoner County, OK, Washington County, OK, Woodward County, OK

The radar

The Norman radar (KTLX), 61 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 70 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 2011-01-20Temperature 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 2011-01-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 271 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1359 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
271 m²/s²
0-3 km storm-relative helicity
382 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.

821 
ACUS11 KWNS 200450
SWOMCD
SPC MCD 200450 
OKZ000-200915-

MESOSCALE DISCUSSION 0038
NWS STORM PREDICTION CENTER NORMAN OK
1050 PM CST WED JAN 19 2011

AREAS AFFECTED...NORTHERN HALF OF OK

CONCERNING...WINTER MIXED PRECIPITATION 

VALID 200450Z - 200915Z

A MIX OF FREEZING DRIZZLE/SOME SLEET WILL YIELD TO
INCREASING/EASTWARD EXPANDING SNOW OVERNIGHT ACROSS THE NORTHERN
HALF OF OK.

WINTRY PRECIPITATION IS EXPECTED TO STEADILY INCREASE ACROSS THE
NORTHERN HALF OF OK OVERNIGHT TO THE NORTH OF A SOUTHWARD ADVANCING
SURFACE COLD FRONT. WITH AN INITIAL BOUT OF DRY AIR IN THE MID
LEVELS...03Z RUC/00Z NAM FORECAST SOUNDINGS GENERALLY IMPLY AN
INITIAL MIX OF FREEZING DRIZZLE/SOME SLEET. OF NOTE...A BAND OF
CONVECTIVE PRECIPITATION CURRENTLY EVOLVING ACROSS WESTERN
OK...EVIDENCED BY SOME CLOUD-GROUND LIGHTNING IN DEWEY COUNTY OK AND
STEEP MID LEVEL LAPSE RATES AS DEDUCED FROM RUC SOUNDINGS...WILL BE
CONDUCIVE FOR A RELATIVELY NARROW CORRIDOR OF SLEET AS ICE IS
INTRODUCED ALOFT. OTHERWISE...SNOW WILL LIKELY BECOME MORE
PREVALENT/EXPAND EASTWARD ACROSS NORTH CENTRAL AND
NORTHEAST/EAST-CENTRAL OK THROUGH THE EARLY MORNING HOURS...WITH
BOUTS OF MODERATE SNOW BECOMING MORE PROBABLE TOWARD 08Z-10Z AND
BEYOND.

..GUYER.. 01/20/2011

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

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

LAT...LON   35409972 36549947 36829564 36209461 35299618 35159770
            35409972

Nearby

Mesoscale Discussions in Oklahoma, 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.