Hail in Mississippi, February 1, 2011

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MEMPHIS TN
928 AM CST TUE FEB 1 2011

.UPDATE...

LARGE AREA OF SHOWERS AND THUNDERSTORMS HAVE BEEN ADVANCING INTO
THE MIDSOUTH THIS MORNING. LOW PRESSURE IS CURRENTLY CENTERED
JUST SOUTH OF HOT SPRINGS ARKANSAS AND IS TRACKING TO THE
NORTHEAST. STORMS HAVE EXHIBITED A WEAKENING TREND AS THEY PUSH
INTO MORE STABLE AIR NORTH OF CENTRAL MS...BUT THIS MAY CHANGE
EARLY THIS AFTERNOON DEPENDING ON THE STORM TRACK. MODELS HAVE
SHIFTED IT EASTWARD A BIT...BUT THIS DOESN/T SEEM LIKELY SINCE
REALITY IS STILL TO THE WEST. ANOTHER REASON THIS UPDATE HAS NOT
UPGRADED THE FAR NORTHWEST INTO A WINTER STORM OR ICE STORM
WARNING DESPITE TEMPERATURES ALREADY IN THE MID 30S IS THE FURTHER
WEST THE STORM TRACKS...THE LONGER IT SHOULD TAKE TO GET FREEZING
AIR INTO THOSE COUNTIES. THIS WILL BE MONITORED OVER THE NEXT FEW
HOURS CLOSELY WITH UPDATES COMING AS NEEDED.

BORGHOFF

&&

.PREV DISCUSSION... /ISSUED 742 AM CST TUE FEB 1 2011/

UPDATE...MOVED UP THE START TIME OF THE WIND ADVISORY AS CORNING
AND WALNUT RIDGE ARKANSAS ARE ALREADY APPROACHING WIND ADVISORY
CRITERIA. ALSO INCREASED MENTION OF THUNDER THIS MORNING ACROSS
THE MID SOUTH. NO OTHER CHANGES MADE AT THIS TIME.

CJC

&&

.PREV DISCUSSION... /ISSUED 540 AM CST TUE FEB 1 2011/

DISCUSSION...10Z SURFACE ANALYSIS PLACES A 1003 MB AREA OF LOW
PRESSURE NEAR SAN ANTONIO TEXAS THIS MORNING WITH A WARM FRONT
EXTENDING FROM THE LOW UP INTO SOUTHEAST MISSOURI BETWEEN PERRYVILLE
AND CAPE GIRARDEAU. ACROSS THE LOWER MISSISSIPPI VALLEY...REGIONAL
WSR-88D RADAR TRENDS SHOW RAIN SHOWERS BECOMING WIDESPREAD ACROSS
ARKANSAS WITH THE DEVELOPMENT OF THUNDERSTORMS ACROSS EAST
TEXAS...SOUTHERN ARKANSAS...AND LOUISIANA. VERY GUSTY WINDS...STRONG
TO SEVERE THUNDERSTORM POTENTIAL AND WINTER WEATHER POTENTIAL TODAY
INTO TONIGHT ARE THE PREDOMINANT CONCERNS IN THIS MORNING/S FORECAST
PACKAGE.

SHORT TERM...(TODAY THROUGH WEDNESDAY)...A VERY COMPLEX AND
DYNAMIC PATTERN IS EVOLVING ACROSS THE SOUTHERN PLAINS AND
MIDDLE/LOWER MISSISSIPPI VALLEYS TODAY AS A STRONG AREA OF LOW
PRESSURE MOVES INTO THE LOWER MISSISSIPPI VALLEY TODAY AND INTO
THE OHIO VALLEY BY LATE TONIGHT. WRF/GFS SHORT TERM MODELS ARE IN
DECENT AGREEMENT EJECTING THE SURFACE LOW OUT OF TEXAS AND
DEEPENING AS IT MOVES INTO THE MID SOUTH THIS AFTERNOON AND
TONIGHT. REGIONAL WSR-88D RADAR TRENDS OVER THE PAST FEW HOURS
HAVE SHOWN A RAPID INCREASE OF SHOWERS AND THUNDERSTORMS ACROSS
ARKANSAS EARLY THIS MORNING. AS THE SURFACE LOW MOVES CLOSER TO
THE FORECAST AREA...SHOWERS AND THUNDERSTORMS WILL BECOME
WIDESPREAD ACROSS THE FORECAST AREA LATER THIS MORNING INTO THIS
AFTERNOON.

MEANWHILE AS THE SURFACE LOW TRACKS ACROSS THE MID SOUTH
TODAY...AN UPPER LEVEL TROUGH WILL BECOME NEGATIVELY TILTED AS IT
ROTATES THROUGH THE LOWER MISSISSIPPI VALLEY THIS AFTERNOON AND
TONIGHT. STRONG MID-LEVEL HEIGHT FALLS...STEEP 700-500 MB LAYER
MID LEVEL LAPSE RATES AT OR ABOVE 7 C/KM...0-1KM STORM RELATIVE
HELICITY VALUES BETWEEN 600-800 M2/S2...AND FAVORABLE UPPER LEVEL
DIVERGENCE ON THE SOUTHERN PERIPHERY OF AN 160KT JET STREAK WILL
HAVE THE POTENTIAL TO PRODUCE STRONG TO PERHAPS SEVERE
THUNDERSTORMS ACROSS PORTIONS OF THE MID SOUTH SOUTH OF I-40
/ESPECIALLY ACROSS NORTH MISSISSIPPI/ THIS AFTERNOON INTO EARLY
EVENING. THE MOST LIKELY MODE OF CONVECTION IS ANTICIPATED TO BE
LINEAR WITH THE POTENTIAL FOR SOME SEGMENTS TO EXHIBIT MINI-
SUPERCELLULAR TYPE CHARACTERISTICS. HOWEVER...A LINGERING CONCERN
AS OF THIS DISCUSSION IS THAT TOO MUCH SHEAR MAY BECOME A LIMITING
FACTOR TO THE OVERALL SEVERE THUNDERSTORM THREAT. IN ADDITION TO THE
SEVERE THUNDERSTORM THREAT...LOCALIZED FLASH FLOODING MAY ALSO BE
POSSIBLE AS PRECIPITABLE WATER VALUES APPROACH 1.5 INCHES.

AS THE SURFACE PRESSURE GRADIENT TIGHTENS ACROSS THE AREA
SOUTHEAST WINDS WILL INCREASE AND BECOME GUSTY ACROSS THE MID
SOUTH BY THIS AFTERNOON WITH SUSTAINED WINDS AVERAGING BETWEEN 20
TO 30 MPH AND GUSTS TO 35/40 MPH. WINDS WILL GRADUALLY VEER WEST
AS THE LOW BEGINS TO DEPART THE MID SOUTH TONIGHT INTO THE OHIO
VALLEY. AS A RESULT...KEPT THE WIND ADVISORY IN EFFECT ACROSS THE
AREA FROM NOON TODAY THROUGH 6 AM WEDNESDAY MORNING.

AS COLDER ARCTIC AIR BEGINS TO FILTER IN BEHIND THE LOW LATER THIS
AFTERNOON INTO THIS EVENING ACROSS ARKANSAS...SHORT TERM MODEL
SOUNDINGS SUGGEST A WARM NOSE ALOFT WILL BE PRESENT AS SURFACE
TEMPERATURES DROP BELOW FREEZING ACROSS NORTHEAST ARKANSAS.
CONSEQUENTLY...THIS WILL RESULT IN PRECIPITATION CHANGING OVER TO
FREEZING RAIN LATE THIS AFTERNOON AND PERHAPS A FREEZING
RAIN/SLEET MIXTURE BEFORE ENDING LATER THIS EVENING ACROSS THIS
AREA. ICE ACCUMULATION AMOUNTS ARE ANTICIPATED TO REMAIN BELOW ONE
QUARTER INCH WITH ANY SLEET ACCUMULATIONS BELOW ONE HALF INCH.
ONGOING WINTER WEATHER ADVISORY SEEMS REASONABLE FOR LAWRENCE AND
RANDOLPH COUNTIES AT THIS TIME AND MADE NO CHANGES. GUSTY WINDS AND
COLD ARCTIC AIR WILL DROP WIND CHILL VALUES INTO THE SINGLE DIGITS
ABOVE ZERO ACROSS PORTIONS OF THE MID SOUTH TONIGHT.

NONETHELESS...THE DAY SHIFT WILL CONTINUE TO MONITOR THE SEVERE
THUNDERSTORM/WIND ADVISORY POTENTIAL...THE NECESSITY FOR ANY
CHANGES/UPGRADES TO THE ONGOING WINTER WEATHER HEADLINES AND THE
POTENTIAL FOR A WIND CHILL ADVISORY TONIGHT. STAY TUNED...

COLD ARCTIC HIGH PRESSURE WILL BUILD INTO THE MID SOUTH WEDNESDAY
WITH HIGH TEMPERATURES STRUGGLING TO REACH 30 DEGREES ACROSS THE
NORTHERN THIRD OF THE FORECAST AREA.

LONG TERM...(THURSDAY THROUGH MONDAY)...AN ACTIVE WEATHER PATTERN
IS EXPECTED TO CONTINUE ACROSS THE LOWER MISSISSIPPI VALLEY LATE
THIS WEEK INTO EARLY NEXT WEEK AS A SERIES OF UPPER LEVEL TROUGHS
EJECT OUT OF THE ROCKIES...DIG INTO THE SOUTHERN PLAINS AND EJECT
OUT OVER THE LOWER MISSISSIPPI VALLEY. THE FIRST OF THE UPPER
LEVEL TROUGHS WILL ARRIVE THURSDAY NIGHT THROUGH SATURDAY MORNING
BRINGING A CHANCE FOR RAIN AND SNOW...AND THE SECOND UPPER LEVEL
TROUGH WILL BRING ANOTHER COLD FRONT AND AN ADDITIONAL CHANCE FOR
RAIN/SNOW THROUGH THE REGION SUNDAY NIGHT THROUGH MONDAY NIGHT.

CJC

&&

.AVIATION...
12Z TAFS

A DEEP SURFACE LOW WAS LOCATED OVER NORTHEAST TX AT DISCUSSION
TIME. KJBR WILL LIKELY SEE FZRA BY MID-AFTERNOON... PERHAPS EARLIER
IF SHALLOW SUBFREEZING AIR SPILLS SOUTH FROM MO FASTER THAN COLDER
NAM MODEL IS INDICATING.

THE REMAINING TERMINALS...INCLUDING KMEM...WILL SPEND THE MORNING
AND EARLY AFTERNOON IN THE WARM SECTOR. IFR/LIFR CIGS WILL PREVAIL...
AS MOISTURE RICH AND MILD GULF AIR IS DRAWN NORTH OF THE SURFACE
LOW...AND RAIN FALLS INTO A RELATIVELY STABLE SURFACE LAYER.

SURFACE LOW PRESSURE WILL MOVE INTO FAR WESTERN KY BY 00Z...WITH
THE ATTENDANT ARCTIC FRONT WILL MOVING THROUGH THE KMEM TRACON IN
THE 21Z/22Z TIME FRAME. TSRA WILL LIKELY ACCOMPANY THE FRONT OVER
NORTH MS.

DRIER LOW LEVEL AIR WILL FILTER INTO THE REGION AFTER 00Z...WITH
MVFR CIGS AND UNRESTRICTED VSBY PREVAILING AREAWIDE BY 03Z.

PWB

&&

.PRELIMINARY POINT TEMPS/POPS...
MEM  60  24  35  18 / 100  50  10  10
MKL  58  25  32  16 / 100  70  10  10
JBR  45  23  27  13 / 100  50  10  10
TUP  61  26  39  22 / 100  70  10  10

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 9 PM CST
     THIS EVENING FOR LAWRENCE-RANDOLPH.

     WIND ADVISORY UNTIL 6 AM CST WEDNESDAY FOR CLAY-CRAIGHEAD-
     CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
     PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.

MO...WIND ADVISORY UNTIL 6 AM CST WEDNESDAY FOR DUNKLIN-PEMISCOT.

MS...WIND ADVISORY UNTIL 6 AM CST WEDNESDAY FOR ALCORN-BENTON MS-
     CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE MS-
     MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
     TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.

TN...WIND ADVISORY UNTIL 6 AM CST WEDNESDAY FOR CARROLL-CHESTER-
     CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-HARDEMAN-HARDIN-
     HAYWOOD-HENDERSON-HENRY-LAKE-LAUDERDALE-MADISON-MCNAIRY-
     OBION-SHELBY-TIPTON-WEAKLEY.

&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MEMPHIS TN
747 AM CST TUE FEB 1 2011

ARZ008-009-017-018-026>028-035-036-048-049-058-MOZ113-115-
MSZ001>017-020>024-TNZ001>004-019>021-048>055-088>092-021200-
ALCORN-BENTON MS-CALHOUN-CARROLL-CHESTER-CHICKASAW-CLAY-COAHOMA-
CRAIGHEAD-CRITTENDEN-CROCKETT-CROSS-DESOTO-DECATUR-DUNKLIN-DYER-
FAYETTE-GIBSON-GREENE-HARDEMAN-HARDIN-HAYWOOD-HENDERSON-HENRY-
ITAWAMBA-LAFAYETTE-LAKE-LAUDERDALE-LAWRENCE-LEE AR-LEE MS-MADISON-
MARSHALL-MCNAIRY-MISSISSIPPI-MONROE-OBION-PANOLA-PEMISCOT-
PHILLIPS-POINSETT-PONTOTOC-PRENTISS-QUITMAN-RANDOLPH-SHELBY-
ST. FRANCIS-TALLAHATCHIE-TATE-TIPPAH-TIPTON-TISHOMINGO-TUNICA-
UNION-WEAKLEY-YALOBUSHA-
747 AM CST TUE FEB 1 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST ARKANSAS...
THE MISSOURI BOOTHEEL...NORTH MISSISSIPPI...AND WEST TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

A LARGE STORM SYSTEM WILL DEVELOP OVER THE SOUTHERN PLAINS AND
PUSH ACROSS THE MID SOUTH TODAY AND TONIGHT. THIS SYSTEM WILL LIKELY
BRING A VARIETY OF INCLEMENT WEATHER TO THE MID SOUTH INCLUDING
THE POTENTIAL FOR HEAVY RAINFALL...WINDY CONDITIONS...SEVERE
THUNDERSTORMS...AND SOME WINTRY PRECIPITATION.

A WIND ADVISORY IS IN EFFECT FOR THE ENTIRE MIDSOUTH THROUGH 6 AM
WEDNESDAY MORNING. SUSTAINED WINDS OF 20 TO 30 MPH WITH GUSTS TO 45
MPH ARE LIKELY.

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS MAINLY SOUTH OF
I-40 THIS AFTERNOON AS NUMEROUS SHOWERS AND THUNDERSTORMS DEVELOP
ACROSS THE LOWER MISSISSIPPI VALLEY TODAY AND MOVE RAPIDLY NORTHEAST.
LOCALIZED HEAVY RAINFALL MAY ALSO ACCOMPANY THE STRONGEST STORMS
THIS AFTERNOON.

RAIN WILL TURN TO FREEZING RAIN AND POSSIBLY SLEET OVER PORTIONS OF
NORTHEAST ARKANSAS LATE THIS AFTERNOON AND EARLY TUESDAY EVENING
BEFORE ENDING. A LIGHT GLAZING OF ICE IS EXPECTED OVER LAWRENCE AND
RANDOLPH COUNTIES WHERE A WINTER WEATHER ADVISORY IS IN EFFECT.

THE COMBINATION OF STRONG WINDS AND COLD TEMPERATURES WILL MAKE WIND
CHILL VALUES APPROACH ZERO OVER NORTHEAST ARKANSAS AND THE MISSOURI
BOOTHEEL WEDNESDAY NIGHT. A WIND CHILL ADVISORY MAY BECOME NECESSARY.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THE PROBABILITY OF WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TODAY IN SUPPORT OF SEVERE WEATHER
OPERATIONS.