Severe Thunderstorm Warning 380, NWS Jackson, MS

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
1059 AM CDT SUN AUG 14 2016

.UPDATE...Have opted to cancel the Falsh Flood Watch for our
southwest zones today. Surface and weakened mid level low was noted
over southwest Arkansas. The resulting deep southerly flow will
continue over our CWA and will maintain extensive cloud cover over
the western half of our area. This has limited insolation this
morning and will limit instability through the afternoon. Although
rainfall is likely this afternoon, rates and amounts should not be
enough to contribute to flash flooding. Heaviest rainfall rates are
expected to occur over the eastern half of our Mississippi zones
where a few breaks in the clouds will allow for greater instability.
Morning cloud cover has led to a slower warmup over much of our CWA
but visible satellite imagery shows breaks in the clouds that will
allow temperatures to achieve forecasted highs. /22/

&&

.AVIATION...MVFR flight categories will again prevail for much of
the day due to ceilings remaining below 3000 feet across much of the
area.  Ceilings should improve later this evening over locations
along and east of the Interstate 55 corridor, with VFR categories
possible at most TAF sites, except KGLH and KGWO, overnight.
Scattered showers and isolated thunderstorms will remain possible
throughout the morning and afternoon hours. Any convection observed
on station could result in a brief degradation to IFR visibilities
and/or ceilings. Winds today will be southerly between 10-15 knots,
gusting up around 20 knots at times.  Winds will again subside to
between 5 knots this evening, and remain such overnight. /19/

&&

.PREV DISCUSSION... /issued 512 AM CDT SUN AUG 14 2016/

DISCUSSION...Today through Monday night,

The threat for flash flooding continues to be a concern over extreme
southwest portions of the area where storm total rainfall is now
exceeding 10 inches in some locations. Per coordination with
SHV/LIX, have opted to keep the flash flood watch going today as it
looks like one more round of potential heavy rain may affect the
area in association with a weakening mid level low center now moving
into Arkansas. Southerly low level flow of ~ 35 knots on the east
side of the low is transporting very moist air (Precipitable Water
near 2.5 inches) northward along the Mississippi River, and this is
helping to maintain a healthy and persistent band of rain. Rainfall
rates haven't been extraordinary, especially by summer standards, but
the continued soaking will keep the moisture primed for rapid runoff
should heavier rainfall materialize later this morning. A deterrent
to heavier rainfall in our area has been the semi-permanent area of
convection along the LA coast, but convection isn't quite as robust
this morning, and this along with increasing influence from the
westerlies will allow a greater threat for significant rainfall over
at least western portions of the forecast area.

To the east of the Mississippi River, over central/eastern MS, a
dominant mid level high is keeping the atmosphere drier (relatively
speaking), and this is resulting in a fairly sharp west-east
gradient in the deep layer moisture. With daytime heating, recent
HRRR runs are pretty consistent showing a developing convective band
that would move east of the current rain area. While a similar model
scenario progged yesterday didn't pan out, there is a better chance
for it to happen today due to reasons stated previously.

As we go into the early week, the westerlies will continue to play a
more prominent role in maintaining a wet weather pattern, but a
fairly tight west to east gradient of rain chances and QPF will
continue. /EC/

Tuesday through Saturday,

On Tuesday, we will have an upper ridge weakness over the Central
and Southern Plains which will be associated with a stationary
surface boundary. This feature will help to lift the old mid level low
into the westerlies. A series of disturbances will push through the
westerlies with some of the energy dipping into the Southern Plains
and into the Lower Mississippi Valley. Meanwhile the Bermuda High
will be centered over the Southeast Atlantic coast,which will help to
push a very moist airmass (2 plus inches pwats) in southerly flow.
The surface boundary will dissipate by Wednesday. As we push into the
weekend models converge on an upper trough which will become flat
across into the region from the north. Another surface boundary will
push toward the region. Otherwise models and their ensembles shows a
rather wet pattern through the period. This will help to develop good
chances of showers and thunderstorms through the period. Could see
some locally heavy downpours. Models show that the best QPF values
will be along and west of MS River. As far as temps are concerned -
rain chances will keep temps below normal with highs in the 80s.
Lows will be mainly in the lower 70s. Looking into early next week
the wet pattern will continue. /17/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       87  73  89  73 /  63  26  42  33
Meridian      90  73  90  73 /  30  20  40  23
Vicksburg     85  73  89  74 /  67  35  45  38
Hattiesburg   88  74  89  74 /  61  20  45  33
Natchez       84  73  87  74 /  68  36  50  38
Greenville    85  73  88  74 /  67  41  45  48
Greenwood     88  73  89  73 /  54  33  33  35

&&

.JAN Watches/Warnings/Advisories...
MS...None.
LA...None.
AR...None.
&&

22/19/EC/17

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
1035 AM CDT SUN AUG 14 2016

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
141930-
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-
1035 AM CDT SUN AUG 14 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE ENTIRE ARKLAMISS REGION.

.DAY ONE...THE REST OF TODAY AND TONIGHT...

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY...

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 SATURDAY.

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&&

...HAZARD LEGEND...

NO SHORT TERM HAZARDS EXPECTED.

...USEFUL WEATHER WEB PAGES (URLS)...

NWS JAN HOME PAGE...
   WWW.WEATHER.GOV/JAN
STAY AWARE, STAY SAFE NWS JAN BRIEFING PAGE...
   WWW.SRH.NOAA.GOV/JAN/?N=SAFE
NWS JAN TROPICAL PAGE...
   WWW.SRH.NOAA.GOV/JAN/?N=TROPICAL
NATIONAL HURRICANE CENTER HOME PAGE...
   WWW.NHC.NOAA.GOV/
FIND NWS JAN ON FACEBOOK...
   WWW.FACEBOOK.COM/NWSJACKSONMS
FOLLOW NWS JAN ON TWITTER...
   @NWSJACKSONMS

   PLEASE CONVERT ALL WEB ADDRESSES TO LOWER CASE BEFORE ENTERING!

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE JACKSON MS
140 PM CDT SUN AUG 14 2016

MSZ032-038-045-141930-
WINSTON MS-CHOCTAW MS-NESHOBA MS-
140 PM CDT SUN AUG 14 2016

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN NESHOBA...
SOUTHEASTERN CHOCTAW AND WESTERN WINSTON COUNTIES UNTIL 230 PM CDT...

AT 139 PM CDT...METEOROLOGISTS WERE TRACKING A STRONG THUNDERSTORM
NEAR STALLO...OR 12 MILES SOUTHWEST OF LOUISVILLE...MOVING NORTH AT
40 MPH.

WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH THIS STORM.

THIS STRONG THUNDERSTORM WILL BE NEAR...
  LOUISVILLE AND MCMILLAN AROUND 200 PM CDT.
  ACKERMAN AROUND 215 PM CDT.
  CHESTER AROUND 220 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS STORM INCLUDE WEIR.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 3280 8930 3310 8932 3328 8932 3329 8933
      3338 8934 3338 8909 3329 8908 3280 8908
TIME...MOT...LOC 1839Z 179DEG 34KT 3298 8919

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SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE JACKSON MS
145 PM CDT SUN AUG 14 2016

MSZ039-141915-
NOXUBEE MS-
145 PM CDT SUN AUG 14 2016

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL NOXUBEE COUNTY UNTIL 215
PM CDT...

AT 145 PM CDT...METEOROLOGISTS WERE TRACKING A STRONG THUNDERSTORM
NEAR MACON...OR 20 MILES NORTHEAST OF PRESTON...MOVING NORTH AT 25
MPH.

WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH THIS STORM.

THIS STRONG THUNDERSTORM WILL BE NEAR...
  BROOKSVILLE AROUND 200 PM CDT.
  DEERBROOK AROUND 205 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS STORM INCLUDE SHUQUALAK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 3296 8850 3296 8872 3329 8876 3329 8848
TIME...MOT...LOC 1845Z 182DEG 24KT 3312 8861

19