Special Weather Statement, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
308 PM CDT SAT JUL 20 2013

.SHORT TERM...SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE
THROUGH THE LATE AFTERNOON AND EVENING AS A WEAK MID TO UPPER LEVEL
LOW SPINS ACROSS LOUISIANA. STORMS WILL DISSIPATE OVERNIGHT WITH THE
LOSS OF HEATING. SOME STRATUS MAY FORM OVERNIGHT THUS PARTLY CLOUDY
SKIES.

THE UPPER LOW WILL WEAKEN AND MOVE SLOWLY EAST ON SUNDAY. THIS SHOULD
HELP TO KICK OFF SCATTERED SHOWERS AND THUNDERSTORMS MAINLY IN THE
AFTERNOON AND EVENING. GOING WITH THE DRIER GFS GUIDANCE SO WILL HAVE
HIGHS IN THE LOWER 90S AND CHANCE POPS. THIS ACTIVITY MAY LINGER A
LITTLE MORE OVERNIGHT SO HAVE KEPT POPS GOING ALL NIGHT SUNDAY NIGHT.

A TRANSITION TO A NORTHWEST FLOW PATTERN WILL BEGIN ON MONDAY. MODELS
INDICATE A WAVE IN THE FLOW SO THERE WILL BE A HIGHER CHANCE OF RAINFALL
ON MONDAY. MOST ACTIVITY SHOULD BE DURING PEAK HEATING BUT CAN NOT
RULE OUT ACTIVITY IN THE MORNING AND CONTINUING INTO MONDAY NIGHT. /SW/

.LONG TERM...IT APPEARS A TRANSITION TO A NORTHWEST FLOW REGIME WILL
BE COMPLETE BY TUESDAY AS THE SUBTROPICAL RIDGE BUILDS TO OUR WEST
AND A LONGWAVE TROUGH REMAINS IN PLACE ACROSS THE EASTERN CONUS. A
FAIRLY ACTIVE PERIOD OF SHOWER AND THUNDERSTORM ACTIVITY LOOKS TO BE
IN STORE FOR AT LEAST THE FIRST HALF OF THE WEEK AS A SERIES OF
DISTURBANCES SWING DOWN THE BACK SIDE OF THE RIDGE AND ACROSS THE
DEEP SOUTH. AT THE SURFACE...A SURFACE HIGH OVER THE GULF WILL KEEP
PLENTY OF LOW LEVEL MOISTURE IN PLACE AS WEST/ SOUTHWESTERLY FLOW
PREVAILS. THE MODELS SHOW MID LEVEL LAPSE RATES STEEPENING AS THE
WEEK WEARS ON IN RESPONSE TO H5 TEMPS FALLING TO -9C AND PERHAPS -10C
BY MID WEEK. THESE VALUES WOULD YIELD RATHER POTENT VERTICAL TOTALS
CLOSING IN ON 28-30C BY WED...COUPLED WITH ABUNDANT AFTERNOON
INSTABILITY IN EXCESS OF 3000J/KG OF SBCAPE. AS SUCH...WE ARE GOING
TO HAVE TO KEEP A CLOSE EYE ON THE SEVERE STORM POTENTIAL THROUGH
THIS PERIOD. PINPOINTING STORM COMPLEXES VERY FAR IN ADVANCE WILL BE
TOUGH IN THIS REGIME...WHICH ISN'T UNUSUAL FOR THE MIDDLE OF SUMMER.
WILL KEEP THE HWO CLEAR FOR NOW...BUT WE MAY NEED TO START MENTIONING
THE SEVERE STORM POTENTIAL OVER THE NEXT DAY OR SO IF THESE MODEL
TRENDS CONTINUE.

THE MODELS ARE ALSO SHOWING A WEAK FRONTAL BOUNDARY SAGGING TOWARD
THE REGION BY WED OR THU WHICH WOULD AID IN CONVECTIVE POTENTIAL...
IF IT CAN GET THIS FAR SOUTH. WE SHALL SEE. BY LATE IN THE WEEK
(FRI-SAT) IT LOOKS LIKE THE SUBTROPICAL RIDGE TO OUR WEST MAY BUILD
THIS WAY SHUNTING THE BETTER PRECIP CHANCES OFF TO OUR EAST.
TEMPERATURES WILL ATTEMPT TO GO ON THE INCREASE AS A RESULT...BUT IF
WE GET SOME DECENT SUMMERTIME RAINS THROUGH THE FIRST PART OF THE
WEEK (WHICH LOOKS PRETTY LIKELY) IT MAY BE TOUGH TO GET OVERLY WARM.
DECIDED TO CUT HIGHS LATE IN THE WEEK AS UPPER 90S OFFERED BY THE
GFS MOS LOOK A LITTLE AGGRESSIVE AT THIS POINT...AND ALSO CUT HIGHS
A BIT THROUGH THE FIRST PART OF THE WEEK TO ACCOUNT FOR THE DECENT
RAIN CHANCES AND CLOUD COVER. /BK/

&&

.AVIATION...ISOLD TSTMS WERE NOTED ON RADAR DEVELOPING OVER THE AREA
AT EARLY AFTN. TSTM COVERAGE IS STILL EXPECTED TO BE GREATER ACROSS
THE SRN HALF OF THE AREA INTO THIS EVNG. VFR CONDITIONS WL PREVAIL
AWAY FROM TSTMS. SITES THAT RECEIVE RAIN THIS AFTN/EVNG WL HAVE A
GREATER CHANCE OF MVFR/IFR VSBY AND CEILING DEVELOPMENT 09-13Z
SUN...OTHERWISE VFR CONDITIONS LOOK TO PREVAIL AT MOST SITES INTO
SUNDAY. S-SW WINDS WL REMAIN LIGHT...GENERALLY LESS THAN 7KTS
THROUGH SUNDAY. SCATTERED TO NUMEROUS COVERAGE OF STORMS IS EXPECTED
SUNDAY AFTN/EVNG. /22/

&&

.PRELIMINARY POINT TEMPS/POPS...
JACKSON       71  93  73  90 /  25  31  28  49
MERIDIAN      71  92  71  90 /  28  40  31  53
VICKSBURG     70  93  73  90 /  26  26  27  40
HATTIESBURG   73  92  73  92 /  28  52  25  55
NATCHEZ       71  91  73  90 /  22  39  27  43
GREENVILLE    72  93  73  91 /  35  29  38  45
GREENWOOD     71  92  73  90 /  36  33  42  49

&&

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

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
148 PM CDT SAT JUL 20 2013

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
211900-
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-
148 PM CDT SAT JUL 20 2013

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

.DAY ONE...TONIGHT AND SUNDAY

STRONG THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING AND AGAIN
SUNDAY AFTERNOON AND EVENING. THE MOST INTENSE STORMS MAY CONTAIN WIND
GUSTS OF 40 TO 50 MPH...DIME TO NICKEL SIZED HAIL AND FREQUENT LIGHTNING.
INCREASING MOISTURE WILL MAKE HEAVY DOWNPOURS MORE LIKELY WITH MOST
STORMS. BURSTS OF HEAVY RAIN IN SHORT PERIODS OVER THE SAME AREAS MAY
LEAD TO WATER COLLECTING ON ROADS...AND MINOR FLOODING OF POOR
DRAINAGE AND LOW LYING AREAS.

.DAYS TWO THROUGH SEVEN...SUNDAY NIGHT THROUGH FRIDAY

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 FRIDAY.

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

22

MSZ035-041-042-202000-
SHARKEY MS-HUMPHREYS MS-YAZOO MS-
202 PM CDT SAT JUL 20 2013

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE JACKSON MS
202 PM CDT SAT JUL 20 2013

A STRONG THUNDERSTORM CAPABLE OF PRODUCING PEA TO DIME SIZE HAIL AND
40 TO 50 MPH WINDS WAS LOCATED 9 MILES SOUTH OF MIDNIGHT AT 202 PM
CDT...MOVING NORTH AT 5 MPH.

VERY HEAVY RAIN ALONG WITH CONTINUOUS CLOUD TO GROUND LIGHTNING ARE
ALSO POSSIBLE WITH THIS STORM.

PEOPLE IN NORTHWESTERN YAZOO...SOUTHERN HUMPHREYS AND NORTHEASTERN
SHARKEY COUNTIES SHOULD MONITOR THIS STORM CLOSELY.

LAT...LON 3308 9043 3306 9043 3284 9046 3284 9069
      3310 9070 3310 9068
TIME...MOT...LOC 1902Z 184DEG 4KT 3292 9057

MME

MSZ061-062-202150-
LINCOLN MS-FRANKLIN MS-
349 PM CDT SAT JUL 20 2013

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE JACKSON MS
349 PM CDT SAT JUL 20 2013

...GROWING CLUSTER OF THUNDERSTORMS MOVING NORTH INTO SOUTH-CENTRAL
MISSISSIPPI...

AN ELONGATED CLUSTER OF OCCASIONALLY STRONG AND SLOW MOVING
THUNDERSTORMS CAPABLE OF PRODUCING 45 MPH WIND GUSTS WAS LOCATED
FROM 3 MILES SOUTHEAST OF BROOKHAVEN TO 10 MILES SOUTH OF LITTLE
SPRINGS AT 348 PM CDT...MOVING NORTH AT 10 MPH.

VERY HEAVY RAIN ALONG WITH OCCASIONAL TO FREQUENT CLOUD TO GROUND
LIGHTNING STRIKES ARE ALSO POSSIBLE WITH THESE STORMS.

HIGH WINDS CAN BRING DOWN TREES AND LARGE LIMBS RESULTING IN SERIOUS
INJURY OR PROPERTY DAMAGE. EXERCISE EXTREME CAUTION WHEN OUTDOORS
DURING SUCH STRONG WINDS...AND BE ESPECIALLY AWARE OF OLDER TREES.

PEOPLE IN EASTERN FRANKLIN AND CENTRAL LINCOLN COUNTIES SHOULD
MONITOR THESE STORMS CLOSELY.

LAT...LON 3147 9078 3170 9056 3170 9041 3169 9041
      3169 9038 3170 9037 3170 9036 3153 9034
      3134 9052 3134 9076
TIME...MOT...LOC 2048Z 175DEG 8KT 3155 9042 3127 9068

BYB