Severe Thunderstorm Warning 519, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
1100 AM CDT MON JUL 4 2011

.UPDATE...

OF PARTICULAR INTEREST THIS MORNING IS THE CONVECTIVE PRECIPITATION
OVER NRN AR/WRN TN IN ASSOCIATION WITH A WEAK SHORTWAVE TROUGH AND FRONTAL
BOUNDARY. AN OUTFLOW BOUNDARY EMANATING FROM THIS CONVECTION IS
SURGING SOUTHWARD THROUGH ERN AR AND INTO NW MS...BUT IT REMAINS TO
BE SEEN HOW MUCH OF A FOCUS THIS WILL SERVE FOR ADDITIONAL
SHOWER/TSTM ACTIVITY THIS AFTN. HAVE INCREASED POPS A BIT ALONG THE
HWY 82 CORRIDOR THIS AFTN/EVNG GIVEN PROGGED MID LEVEL HEIGHT FALLS
AND POTENTIAL OUTFLOW BOUNDARY EFFECTS. OTHERWISE...THE FORECAST IS
GENERALLY ON TRACK WITH SOME RISK FOR PULSE-SEVERE STORMS PRIMARILY
DURING THE LATE AFTN/EARLY EVNG. /EC/

&&

.PREV DISCUSSION... /ISSUED 402 AM CDT MON JUL 4 2011/

SHORT TERM...THE AIR MASS WILL REMAIN UNSTABLE IN THE SHORT TERM
WITH HEALTHY CAPE FIELDS...LAPSE RATES ABOVE 7 DEGREES AND LIFTED
INDICES IN THE UPPER 20S. UPPER RIDGING WILL CONTINUE TO GIVE WAY
WITH WEAK CYCLONIC FLOW DEVELOPING INTO NRN ZONES LATE IN THE DAY.
DIFFUSE UPPER TROUGHING WILL WORK ITS WAY SWD INTO THE FORECAST AREA
BY TUESDAY. SATELLITE PIX SHOW A FETCH OF DEEPER MOISTURE HAS WORKED
INTO THE AREA FROM THE EAST. ANOTHER REGION OF DEEPER MOISTURE WILL
WORK ITS WAY SWD INTO THE REGION AHEAD OF THE APPROACHING UPPER
TROUGH.

MAV MOS POPS REFLECT SLIGHTLY DRIER AIR OVER NRN ZONES...ESPECIALLY
NWRN ZONES...BUT POPS FOR NERN ZONES LOOK TOO LOW. HAVE OPTED TO USE
AVERAGE ENSEMBLE GFS MOS NUMBERS WHICH PAINT HIGHER RAIN CHANCES
OVER EAST CENTRAL ZONES WHERE MOISTURE ADVECTION WILL BE A LITTLE
HIGHER TODAY. MAV MOS POPS ALSO LOOK TOO LOW OVER NRN ZONES TOMORROW
WHEN THE UPPER TROUGH AND ASSOCIATED MOISTURE FETCH APPROACH FROM
THE NORTH. HAVE TRENDED ONCE AGAIN WITH AVERAGE ENSEMBLE GFS MOS
NUMBERS WITH GENERALLY SCT CONVECTION ACROSS THE FORECAST AREA FOR
TUESDAY. CONTINUED TREND OF AVERAGE ENSEMBLE GFS MOS FOR NIGHTTIME
POPS... DECREASING CONVECTIVE COVERAGE OVERNIGHT.

EXPECT TEMPERATURES TO BE A LITTLE LOWER TODAY THAN SUNDAY DUE TO
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS...INCREASED CLOUD
COVER AND DECREASING HEIGHTS. EVEN SO...INCREASED HIGHS SLIGHTLY
OVER MOS NUMBERS FOR TODAY IN CONSIDERATION OF WARM SOIL TEMPS AND
THE RECENT COOLER MAV MOS BIAS ON AFTERNOON TEMPS.

LONG TERM...(WEDNESDAY THROUGH SUNDAY)...THE UPSWING IN AFTERNOON
SHOWER AND THUNDERSTORM ACTIVITY WILL PERSIST THROUGH THE WEEKEND AS
A WARM AND UNSTABLE AIRMASS DRAPED OVER THE DEEP SOUTH REMAINS IN
PLACE. NO REAL CHANGE IS EXPECTED AT THE SURFACE THROUGH THE WEEK AS
DEW POINTS HANG IN THE LOW TO MID 70S...ACCOMPANIED BY LIGHT
SOUTHERLY SURFACE WINDS. A WEAK FRONTAL BOUNDARY LIMPING INTO
NORTHERN MS ON WEDNESDAY WILL PROVIDE A FOCUS FOR DEEP MOIST
CONVECTION IN THAT VICINITY THROUGH THE WEEK...WITH TYPICAL
SUMMERTIME CONVECTION EXPECTED ELSEWHERE AS INTENSE SURFACE HEATING
RAMPS UP THE INSTABILITY. ENHANCED SEA BREEZE ACTIVITY WILL HAVE TO
BE MONITORED ACROSS SOUTHERN ZONES FOR POSSIBLE FOCUSING OF
CONVECTIVE POTENTIAL IN THOSE AREAS.

AS FOR SEVERE POTENTIAL...WEDNESDAY APPEARS TO HAVE AT LEAST A
DECENT SHOT AT A FEW SEVERE STORMS PRIMARILY DUE TO AN UPPER
TROPOSPHERIC LOW DRIFTING NORTH FROM THE GULF OF MEXICO THAT WILL
PROVIDE SOME ADDED FORCING...COUPLED WITH A VERY UNSTABLE AIRMASS
MARKED BY VERTICAL TOTALS IN EXCESS OF 26C. PRIMARY RISK WITH
ANYTHING THAT DEVELOPS WILL BE DAMAGING WIND GUSTS FROM MICROBURSTS
THANKS TO STEEP LOW LEVEL LAPSE RATES AND ASSOCIATED HIGH VALUES OF
DCAPE...AS WELL AS LOCALLY HEAVY RAINFALL UNDER THUNDERSTORM CORES.
VERTICAL TOTAL VALUES DROP-OFF SOMEWHAT THURSDAY INTO THE WEEKEND
WHICH SHOULD HELP LIMIT UPDRAFT INTENSITIES THE LATTER HALF OF THE
WEEK...KEEPING SEVERE POTENTIAL MORE ISOLATED IN NATURE.
REGARDLESS...CONVECTIVE ACTIVITY CAN BE EXPECTED EACH DAY STARTING
IN THE EARLY AFTERNOON HOURS DIMINISHING IN THE MID TO LATE EVENING
HOURS.

ON THE TEMPERATURE FRONT REALLY NOT EXPECTING MUCH CHANGE THROUGH
THE WEEK. HIGHS SHOULD TOP IN THE MID 90 DEGREE RANGE EACH
AFTERNOON...JUST A TAD ABOVE NORMAL. HEAT INDEX VALUES WILL RISE TO
NEAR 100 DEGREES EACH DAY. OVERNIGHT LOWS WILL FALL INTO THE LOW TO
MID 70S...NEAR NORMAL FOR EARLY JULY. /BK/

&&

.AVIATION...
A FEW SITES REPORTED VISIBILITY RESTRICTIONS TO 5SM BETWEEN 11-12Z
THIS MORNING BUT THE PATCHY FOG HAS BURNED OFF AND VFR CONDITIONS
WERE BEING REPORTED AREAWIDE. VFR CONDITIONS WILL PREVAIL UNTIL
ISOLATED TO SCT SHWRS AND TSTMS DEVELOP DURING THE AFTERNOON. SCT-BKN
DECKS 3-5K FEET CAN BE EXPECTED THIS AFTERNOON WITH LCL MVFR/IFR
CIGS/VSBYS IN TSTMS. A FEW TSTMS WILL HAVE THE POTENTIAL TO BECOME
SEVERE WITH WIND GUSTS TO 60 MPH AND QUARTER SIZE HAIL. MOST OF THE
CONVECTION WILL DISSIPATE BY 03Z THU BUT MODELS ALSO INDICATE SOME
ACTIVITY MAY PERSIST THROUGH THE NIGHT IN THE NORTH AS A BOUNDARY
SAGS FURTHER SOUTH. A BRIEF PERIOD BETWEEN 10Z AND 12Z OF 3-5SM
VISIBILITIES WILL AGAIN BE POSSIBLE... ESPECIALLY AREAS THAT RECEIVE
SIGNIFICANT RAINFALL TODAY. /22/

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
500 AM CDT MON JUL 4 2011

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
051000-
ASHLEY-CHICOT-MOREHOUSE-WEST CARROLL-EAST CARROLL-RICHLAND-
MADISON LA-FRANKLIN LA-CATAHOULA-TENSAS-CONCORDIA-BOLIVAR-
SUNFLOWER-LEFLORE-GRENADA-CARROLL-MONTGOMERY-WEBSTER-CLAY-LOWNDES-
CHOCTAW-OKTIBBEHA-WASHINGTON-HUMPHREYS-HOLMES-ATTALA-WINSTON-
NOXUBEE-ISSAQUENA-SHARKEY-YAZOO-MADISON MS-LEAKE-NESHOBA-KEMPER-
WARREN-HINDS-RANKIN-SCOTT-NEWTON-LAUDERDALE-CLAIBORNE-COPIAH-
SIMPSON-SMITH-JASPER-CLARKE-JEFFERSON-ADAMS-FRANKLIN MS-LINCOLN-
LAWRENCE-JEFFERSON DAVIS-COVINGTON-JONES-MARION-LAMAR-FORREST-
500 AM CDT MON JUL 4 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL MISSISSIPPI...
NORTHEAST LOUISIANA...AND EXTREME SOUTHEAST ARKANSAS.

.DAY ONE...TODAY AND TONIGHT

ISOLATED SEVERE THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON AND
EVENING. THESE STORMS WILL HAVE THE POTENTIAL FOR DAMAGING WIND
GUSTS TO 60 MPH...QUARTER SIZE HAIL AND DANGEROUS CLOUD TO GROUND
LIGHTNING.

AFTERNOON HEATING WILL PRODUCE A FEW SEVERE THUNDERSTORMS IN THE
MOIST AND UNSTABLE AIR MASS CURRENTLY IN PLACE ACROSS THE AREA. WITH
MANY OUTDOOR ACTIVITIES TAKING PLACE THIS 4TH OF JULY HOLIDAY...
PLEASE REMEMBER TO TAKE COVER ONCE THUNDER IS HEARD AS LIGHTNING CAN
STRIKE MANY MILES FROM THE THUNDERSTORM.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER CALL TO ACTION STATEMENT...
THE ACTIVATION OF STORM SPOTTERS...HAM RADIO OPERATORS...AND
EMERGENCY MANAGEMENT PERSONNEL IN SUPPORT OF SEVERE WEATHER
OPERATIONS IS NOT EXPECTED THROUGH NEXT SUNDAY.

FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT
WWW.SRH.NOAA.GOV/JAN.

03

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE JACKSON MS
222 PM CDT MON JUL 4 2011

MSZ051-052-057-058-042020-
CLARKE MS-JASPER MS-NEWTON MS-LAUDERDALE MS-
222 PM CDT MON JUL 4 2011

A LINE OF STRONG THUNDERSTORMS CAPABLE OF PRODUCING PEA TO DIME SIZE
HAIL AND 40 TO 50 MPH WINDS WAS LOCATED FROM 3 MILES WEST OF ALAMUCHA
TO PAULDING AT 222 PM CDT...MOVING NORTHWEST AT 30 MPH.

PEOPLE IN LAUDERDALE...SOUTHERN NEWTON...JASPER AND NORTHWESTERN
CLARKE COUNTIES SHOULD MONITOR THESE STORMS CLOSELY.

LAT...LON 3184 8914 3242 8931 3258 8856 3235 8841
      3232 8842
TIME...MOT...LOC 1922Z 155DEG 24KT 3237 8853 3205 8904

MME

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JACKSON MS
223 PM CDT MON JUL 04 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0220 PM     HAIL             ROXIE                   31.51N 91.07W
07/04/2011  E0.75 INCH       FRANKLIN           MS   TRAINED SPOTTER

&&

JCULIN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE JACKSON MS
236 PM CDT MON JUL 4 2011

MSZ048-053-054-059-061-062-042035-
JEFFERSON MS-CLAIBORNE MS-HINDS MS-FRANKLIN MS-LINCOLN MS-COPIAH MS-
236 PM CDT MON JUL 4 2011

A LINE OF STRONG THUNDERSTORMS CAPABLE OF PRODUCING PEA TO DIME SIZE
HAIL AND 40 TO 50 MPH WINDS WAS LOCATED FROM 4 MILES EAST OF GALLMAN
TO 6 MILES SOUTH OF CASEYVILLE AT 236 PM CDT...MOVING NORTHWEST AT 10
MPH.

PEOPLE IN COPIAH...NORTHWESTERN LINCOLN...NORTHEASTERN FRANKLIN...
SOUTH CENTRAL HINDS...SOUTHEASTERN CLAIBORNE AND EASTERN JEFFERSON
COUNTIES SHOULD MONITOR THESE STORMS CLOSELY.

LAT...LON 3193 9018 3156 9064 3175 9093 3219 9045
TIME...MOT...LOC 1936Z 138DEG 7KT 3193 9032 3159 9070

MME

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JACKSON MS
302 PM CDT MON JUL 04 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0145 PM     TSTM WND GST     WESSON                  31.70N 90.40W
07/04/2011  E50.00 MPH       COPIAH             MS   PUBLIC

            TREE LIMBS ON SOME POWERLINES RESULTING IN SOME POWER
            OUTAGES.

0229 PM     TSTM WND GST     5 W ELLISVILLE          31.60N 89.29W
07/04/2011  E50.00 MPH       JONES              MS   LAW ENFORCEMENT

            TREE DOWN ACROSS HWY 588 AT OAKEY WOODS LANE

&&

JCULIN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JACKSON MS
306 PM CDT MON JUL 04 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0145 PM     TSTM WND DMG     WESSON                  31.70N 90.40W
07/04/2011                   COPIAH             MS   LAW ENFORCEMENT

            3 TREES DOWN ACROSS ROADS AND PART OF THE ROOF OF A SHED
            BLOWN OFF.

&&

JCULIN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JACKSON MS
312 PM CDT MON JUL 04 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0220 PM     HAIL             5 N ELLISVILLE          31.67N 89.21W
07/04/2011  E1.00 INCH       JONES              MS   UNKNOWN

            RELAYED BY BROADCAST MEDIA

&&

JCULIN