Mesoscale Discussion 101

Issued

Feb 9, 2011, 10:03 AM CST (16:03 UTC)

Expired

Feb 9, 2011, 4:00 PM CST

In force

6 hr

Issued by

the Storm Prediction Center

The Little Rock radar (KLZK), 63 km from the middle of the area, began a volume at 16:05 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.

183 
ACUS11 KWNS 091604
SWOMCD
SPC MCD 091603
TNZ000-MSZ000-MOZ000-ARZ000-LAZ000-TXZ000-OKZ000-092200-

MESOSCALE DISCUSSION 0101
NWS STORM PREDICTION CENTER NORMAN OK
1003 AM CST WED FEB 09 2011

AREAS AFFECTED...ERN OK...FAR NE TX...AR...NRN LA...WRN TN...NW MS

CONCERNING...HEAVY SNOW

VALID 091603Z - 092200Z

SNOWFALL WILL GRADUALLY INCREASE IN THE ARKLATEX AND LOWER TO MID-MS
VALLEY THIS AFTERNOON. SNOWFALL RATES SHOULD REACH 1 INCH PER HOUR
ACROSS CNTRL AND ERN AR...NW MS AND WRN TN. A MIX OF RAIN...SLEET
AND SNOW SHOULD EXIST FROM FAR NE TX EWD ACROSS FAR NRN LA INTO
WCNTRL MS.

A LARGE AREA OF SNOW IS CURRENTLY ONGOING ACROSS ERN OK AND AR
LOCATED ALONG AND TO THE EAST OF A WELL-DEFINED INVERTED SFC TROUGH.
EAST OF THE SFC TROUGH SFC WINDS ARE NELY WHICH COMBINED WITH WARM
ADVECTION AND STRONG ISENTROPIC LIFT WILL CREATE CONDITIONS
FAVORABLE FOR HEAVY SNOW THIS AFTERNOON. THE HEAVIEST SNOW IS
LOCATED IN ERN OK AND NW AR JUST AHEAD OF A VORTICITY MAX IN NE OK.
THE ASSOCIATED UPPER-LEVEL TROUGH WILL MOVE EWD ACROSS OK INCREASING
LARGE-SCALE ASCENT ACROSS THE OZARKS. THIS SHOULD RESULT IN A
GRADUAL INCREASE IN SNOWFALL RATES ACROSS CNTRL AND SRN AR LATER
THIS AFTERNOON WITH UP TO 1 INCH PER HOUR RATES BECOMING LIKELY
ESPECIALLY AFTER 18Z.

FURTHER TO THE SOUTH FROM NE TX ENEWD ACROSS FAR NRN LA INTO NCNTRL
MS...SFC TEMPS CURRENTLY RANGE FROM AROUND 32 F IN NCNTRL MS TO THE
MID TO UPPER 30S F IN THE VICINITY OF SHREVEPORT LA. HOWEVER...NORTH
TO NELY SFC WINDS SHOULD ENABLE SFC TEMPS TO DROP BELOW FREEZING
ACROSS MOST OF THIS CORRIDOR THIS AFTERNOON. FORECAST SOUNDINGS
ACROSS NRN LA AND NCNTRL MS SHOW MOST OF THE COLUMN WILL BE BELOW
FREEZING SUGGESTING RAIN SHOULD QUICKLY CHANGEOVER TO SLEET AND MAY
BE MIXED WITH SNOW. AS SFC TEMPS COOL LATER THIS AFTERNOON...A
TRANSITION TO ALL SNOW APPEARS LIKELY AND 1 INCH PER HOUR SNOWFALL
RATES MAY OCCUR.

..BROYLES.. 02/09/2011

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

ATTN...WFO...OHX...PAH...MEG...JAN...LZK...SHV...TSA...FWD...

LAT...LON   34989529 36139399 36429088 36338852 35478796 34458847
            33119007 32539187 32309356 32319474 33029550 33799568
            34989529

Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Mississippi, 2011Mesoscale Discussions in Tennessee, 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.