Mesoscale Discussion 62

Issued

Jan 31, 2011, 11:29 PM CST (05:29 UTC)

Expired

Feb 1, 2011, 4:30 AM CST

In force

5 hr

Issued by

the Storm Prediction Center

The Dyess AFB radar (KDYX), 41 km from the middle of the area, began a volume at 05:29 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.

687 
ACUS11 KWNS 010530
SWOMCD
SPC MCD 010529
OKZ000-TXZ000-011030-

MESOSCALE DISCUSSION 0062
NWS STORM PREDICTION CENTER NORMAN OK
1129 PM CST MON JAN 31 2011

AREAS AFFECTED...PORTIONS W-CENTRAL/SW TX THROUGH N-CENTRAL
TX...PORTIONS S-CENTRAL/SERN OK.

CONCERNING...WINTER MIXED PRECIPITATION

VALID 010529Z - 011030Z

NWRN PORTIONS OF PRECIP BAND...FROM W-CENTRAL TX NEWD ACROSS
PORTIONS N-CENTRAL TX...SHOULD EXPERIENCE TRANSITION FROM RAIN TO
FREEZING RAIN AND SLEET AS SFC FREEZING LINE MOVES SWD BENEATH
ACTIVITY...WITH LIQUID EQUIVALENT RATES COMMONLY .25 INCH/HOUR AND
BRIEF/ISOLATED RATES .5 INCH/HOUR.  EMBEDDED TSTMS ALSO MAY PRODUCE
ISOLATED SVR HAIL.  PRECIP ACROSS WRN PORTIONS OF AREA SHOULD CHANGE
TO SNOW AFTER ABOUT 06Z WITH SPORADIC 1 INCH/HOUR RATES POSSIBLE.

05Z SFC ANALYSIS INDICATED FREEZING LINE NEAR ADM...20 NNW MWL...40
NW SJT...15 S MAF...AND EXPECTED TO CONTINUE MOVING SWD FROM
COMBINATION OF POSTFRONTAL CAA...DIABATIC SFC COOLING AND WET-BULB
EFFECTS.  PRECIP BAND INITIALLY EXTENDING FROM CROCKETT COUNTY NEWD
TO MONTAGUE/COOKE COUNTIES IS FCST TO TRANSLATE EWD ACROSS EDWARDS
PLATEAU...WRN/NRN HILL COUNTRY AND N-CENTRAL TX...BUT AT SLOWER PACE
THAN SEWD SHIFT OF SFC FREEZING LINE.  THIS EWD SHIFT OF PRECIP
SHOULD COINCIDE WELL WITH THAT OF MAX IN 700-850 MB LAYER
FRONTOGENESIS...IMPINGING UPON REGIME OF MOIST ADVECTION/TRANSPORT
ACCOMPANYING BROAD/30-35 KT LLJ.  ELEVATED MUCAPE 250-700 J/KG IS
EXPECTED JUST E OF MAIN CONVECTIVE BAND...WITH 40-55 KT EFFECTIVE
SHEAR SUPPORTING SOME ROTATION ALOFT IN RELATIVELY DISCRETE
CELLS...AND RELATED ENHANCEMENT TO MIDLEVEL UPDRAFT STRENGTH AND
HAIL GENERATION POTENTIAL.

MEANWHILE...FREEZING RAIN IS LIKELY IN REAR PORTION OF CONVECTIVE
PLUME...THEN TRANSITION TO SLEET AND SNOW IN WWD/NWWD
CROSS-SECTION...AS SUPERFREEZING LAYER ABOVE FRONTAL SURFACE BECOMES
MORE VERTICALLY COMPRESSED AND WEAKER IN MAGNITUDE.  RAIN MAY CHANGE
STRAIGHT TO SNOW AFTER 06Z ACROSS PERMIAN BASIN REGION...AS
CONTINUED DEEPENING OF POSTFRONTAL BOUNDARY LAYER COINCIDES WITH
COOLING OF COLUMN ALOFT...AND LARGE-SCALE DCVA/ASCENT AHEAD OF
STG/APCHG SHORTWAVE TROUGH.

..EDWARDS.. 02/01/2011

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

ATTN...WFO...TSA...FWD...OUN...SJT...LUB...MAF...

LAT...LON   32669704 31589896 30730036 30890212 31920177 33080011
            33019971 33189866 33649769 34329672 34209587 32669704

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

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.