Severe Thunderstorm Warning 280, NWS Memphis, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEMPHIS TN
911 PM CDT SUN JUL 12 2009

.DISCUSSION...01Z SURFACE ANALYSIS PLACES A WEAK QUASI-STATIONARY
BOUNDARY ACROSS NORTHERN ARKANSAS AND NORTHWEST TENNESSEE.
SCATTERED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS
GIBSON/CARROLL COUNTIES OVER THE PAST HOUR ON THE BACK EDGE OF A
DEPARTING MCS. THIS CONVECTIVE ACTIVITY HAS BEEN SLOWLY MOVING
SOUTHEAST TOWARDS MIDDLE TENNESSEE. TEMPERATURES ACROSS THE MID
SOUTH THIS EVENING ARE PREDOMINANTLY IN THE 80S AS OF 8 PM CDT.
MAIN FORECAST CHALLENGE THIS EVENING IS CONVECTIVE POTENTIAL
ACROSS THE FORECAST AREA FOR THE REMAINDER OF THE NIGHT.

FOR NOW...THE 00Z RUC SEEMS TO HAVE THE BEST HANDLE ON THE
CONVECTIVE TRENDS. THE ATMOSPHERE ACROSS THE MID SOUTH THIS
EVENING REMAINS HIGHLY UNSTABLE WITH SURFACE BASED CAPE VALUES AT
OR ABOVE 3000 J/KG...LI/S AROUND -8 AND MODERATELY STEEP 700-500
MB LAYER MID LEVEL LAPSE RATES AROUND 6.5 C/KM. HOWEVER...UNCERTAINTY
REMAINS AS TO WHETHER A TRIGGERING MECHANISM WILL BE IN PLACE TO
PRODUCE ADDITIONAL DEVELOPMENT ACROSS THE FORECAST AREA FOR THE
REMAINDER OF THE NIGHT. UPPER AIR PROFILERS/RUC ANALYSIS SUGGEST
A SUBTLE 700 MB SHORTWAVE LOCATED ACROSS SOUTH CENTRAL MISSOURI
MAY POTENTIALLY BE THE TRIGGERING MECHANISM NEEDED FOR ADDITIONAL
CONVECTIVE DEVELOPMENT. HOWEVER...FOR NOW WILL CONTINUE TO
MONITOR CONVECTIVE TRENDS BEFORE MAKING ADJUSTMENTS DOWNWARD TO
RAIN CHANCES OVERNIGHT.

CJC
&&

.PREV DISCUSSION... /ISSUED 641 PM CDT SUN JUL 12 2009/

UPDATE...

UPDATED AVIATION DISCUSSION FOR 00Z TAFS.

DISCUSSION...

/ISSUED 233 PM CDT SUN JUL 12 2009/

LATEST RADAR IMAGES CONTINUE TO SHOW AN MCS TRACKING ACROSS
SOUTHWEST ILLINOIS. THE MCS IS STARTING TO TURN TOWARD THE
SOUTHEAST AS THE UPPER RIDGE CONTINUES TO WEAKEN WHICH MAY PUT THE
REMNANTS ENTERING NORTHEASTERN PORTIONS OF THE CWA AROUND 00Z.
SOME OF THE STORMS COULD BE STRONG TO SEVERE THIS EVENING WITH
DAMAGING WINDS AND FLASH FLOODING BEING THE MAIN THREATS.
ADDITIONAL MCS DEVELOPMENT COULD OCCUR NORTH OF THE AREA AND MOVE
SOUTH INTO THE CWA DURING THE OVERNIGHT HOURS. WILL CONTINUE WITH
THE HIGHEST POPS ACROSS THE NORTHEAST. WITH THE CLOUD COVER AND
THE RAIN...LOWS MAY BE A TOUCH COOLER THAN PREVIOUSLY THOUGHT WITH
READINGS IN THE LOWER TO MID 70S.

MONDAY INTO MONDAY NIGHT...STATIONARY FRONT WILL BE LOCATED ALONG
THE MO/AR AND KY/TN BORDERS. REDEVELOPMENT WOULD LIKELY OCCUR ALONG
THIS FRONT BY MONDAY AFTERNOON AS ANOTHER SHORTWAVE MOVES THROUGH
THE CWA. ACTIVITY SHOULD DIE OFF DURING THE OVERNIGHT HOURS OF
MONDAY NIGHT. HIGHS WILL BE COOLER WITH READINGS IN THE MID 80S TO
LOWER 90S. LOWS WILL BE IN THE LOWER TO MID 70S.

TUESDAY INTO WEDNESDAY...UPPER RIDGE STRENGTHENS OVER THE AREA AS
THE FRONT PUSHES BACK TO THE NORTH. CONDITIONS SHOULD BE DRY. CAN/T
RULE OUT AN ISOLATED SHOWER OR THUNDERSTORM BUT NOT ENOUGH TO PUT
POPS IN THE FORECAST. WITH HUMIDITY LEVELS REMAINING HIGH ACROSS THE
AREA AND WARMER TEMPERATURES MOVING INTO THE REGION...HEAT INDICES
MAY REACH AT OR ABOVE 105 DEGREES. THUS HEAT ADVISORIES MAY BE
NEEDED FOR TUESDAY AND WEDNESDAY. HIGHS WILL BE IN THE MID TO UPPER
90S. LOWS WILL BE MUGGY WITH READINGS IN THE MID TO UPPER 70S.

WEDNESDAY NIGHT INTO FRIDAY...COLD FRONT WILL SAG SOUTH INTO THE
MIDSOUTH AND BRING CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE
AREA. BEHIND THE FRONT COOLER TEMPERATURES WILL MOVE INTO THE AREA.
HIGHS WILL BE IN THE UPPER 80S TO LOWER 90S.

FRIDAY NIGHT INTO SATURDAY...COLD FRONT MAY STALL OUT ALONG
SOUTHWEST PORTIONS OF THE CWA KEEPING CHANCES FOR RAIN ACROSS THIS
PART OF THE CWA. MEANWHILE...DRIER AND COOLER AIR WILL FILTER INTO
THE NORTHEAST PORTIONS OF THE CWA. HIGHS WILL BE IN THE MID TO UPPER
80S. LOWS WILL BE IN THE MID 60S TO AROUND 70 DEGREES.

SUNDAY...SFC HIGH PRESSURE WILL BUILD INTO THE CWA FROM THE
NORTHEAST BRINGING DRIER AIR INTO THE ENTIRE MIDSOUTH. HIGHS WILL BE
IN THE MID TO UPPER 80S.

KRM

&&
.AVIATION...

00Z TAFS

THROUGH 06Z...MAINLY VFR CONDITIONS ARE EXPECTED AT ALL TAF
SITES...UNLESS A SITE GETS DIRECTLY AFFECTED BY TSRA/SHRA.

BELIEVE ISOLATED TO SCATTERED TSRA WILL DEVELOP OVER THE AREA AS A
COLD FRONT APPROACHES..FIRST IN THE 00-03Z TIME FRAME OVER NORTHWEST
TENNESSEE...MISSOURI BOOTHEEL...AND NORTHEAST ARKANSAS...THEN MOVE
SOUTHEAST. HAVE DELAYED VCTS AT ALL LOCATIONS EXCEPT KMKL. IF TSRA
BECOME BETTER ORGANIZED...WILL AMEND TO ADD TEMPO MENTION OF BRIEF
GUSTY WINDS AND MVFR/IFR CONDITIONS...WHICH WOULD ONLY OCCUR LESS
THAN 1 HOUR IN DURATION. HAVE NO DOUBT THAT TSRA/SHRA WILL OCCUR
OVER THE AREA...PINPOINTING EXACTLY WHEN AND WHERE REMAINS
DIFFICULT.

06-13Z...BELIEVE TSRA/SHRA WILL BE IN THE KMEM AND KTUP AREAS.
BRIEF GUSTY WINDS AND MVFR/IFR CONDITIONS IN TSRA ARE POSSIBLE AT
KMEM AND KTUP DURING THIS TIME FRAME. KEPT MVFR TEMPOS AT ALL TAF
SITES EXCEPT KMEM 10-13Z...OTHERWISE MAINLY VFR CONDITIONS SHOULD
PREVAIL.

BEYOND 13Z...GENERALLY VFR CONDITIONS ARE EXPECTED AT THIS TIME.
THERE IS A SMALL CHANCE OF MVFR CONDITIONS AT KJBR AND KMKL
THROUGH 17Z JUST NORTH OF THE COLD FRONT...BUT LEFT MENTION OUT
FOR NOW WITH LOW CONFIDENCE OF OCCURRENCE. COLD FRONT WILL SLOWLY
SAG SOUTH AND SHIFT WINDS TO THE NORTH...AS WELL AS PUSH TSRA/SHRA
FARTHER SOUTH. ADDED VCTS AT KMEM AND KTUP AFTER 18Z AS THESE TWO
SITES HAVE THE BEST CHANCES FOR TSRA.

MBS

&&

.PRELIMINARY POINT TEMPS/POPS...
MEM  76  92  76  96 /  40  40  20  10
MKL  70  86  71  93 /  50  50  20  10
JBR  73  88  74  97 /  40  40  20  10
TUP  75  90  73  95 /  40  40  20  10

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MEMPHIS TN
821 PM CDT SUN JUL 12 2009

TNZ003-004-020-021-054-055-130215-
DECATUR TN-CARROLL TN-GIBSON TN-HENRY TN-WEAKLEY TN-HENDERSON TN-
821 PM CDT SUN JUL 12 2009

...THIS SIGNIFICANT WEATHER ALERT IS FOR...

  DECATUR COUNTY IN TENNESSEE...
  CARROLL COUNTY IN NORTHWEST TENNESSEE...
  EAST CENTRAL GIBSON COUNTY IN NORTHWEST TENNESSEE...
  SOUTHWESTERN HENRY COUNTY IN NORTHWEST TENNESSEE...
  SOUTHERN WEAKLEY COUNTY IN NORTHWEST TENNESSEE...
  HENDERSON COUNTY IN SOUTHWEST TENNESSEE...

A STRONG THUNDERSTORM PRODUCING PEA TO DIME SIZE HAIL AND 40 TO 50
MPH WINDS WAS LOCATED OVER HUNTINGDON AT 821 PM CDT...MOVING
SOUTHEAST AT 45 MPH.

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

THIS STORM IS INTENSIFYING AND COULD BECOME SEVERE RAPIDLY.

PEOPLE IN CARROLL...DECATUR...GIBSON...HENDERSON...HENRY AND WEAKLEY
COUNTIES...INCLUDING LOCATIONS NEAR HUNTINGDON...LEXINGTON...
MCKENZIE...NATCHEZ TRACE STATE FOREST AND NATCHEZ TRACE STATE PARK...
SHOULD MONITOR THIS STORM CLOSELY THIS SIGNIFICANT WEATHER ALERT IS
IN EFFECT UNTIL 915 PM CDT. THIS SIGNIFICANT WEATHER ALERT ALSO
INCLUDES BEECH LAKE...PIN OAK LAKE AND PINE LAKE.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MEMPHIS TN
915 PM CDT SUN JUL 12 2009

TNZ021-054-055-130245-
DECATUR TN-CARROLL TN-HENDERSON TN-
915 PM CDT SUN JUL 12 2009

...THIS SIGNIFICANT WEATHER ALERT IS FOR...

  DECATUR COUNTY IN TENNESSEE...
  EASTERN CARROLL COUNTY IN NORTHWEST TENNESSEE...
  NORTHEASTERN HENDERSON COUNTY IN SOUTHWEST TENNESSEE...

A STRONG THUNDERSTORM PRODUCING 40 TO 50 MPH WINDS WAS LOCATED 7
MILES SOUTHWEST OF BRUCETON AT 915 PM CDT...MOVING SOUTHEAST AT 30
MPH.

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

THIS STORM IS INTENSIFYING AND COULD BECOME SEVERE RAPIDLY.

PEOPLE IN CARROLL...DECATUR AND HENDERSON COUNTIES...INCLUDING
LOCATIONS NEAR NATCHEZ TRACE STATE FOREST AND NATCHEZ TRACE STATE
PARK...SHOULD MONITOR THIS STORM CLOSELY THIS SIGNIFICANT WEATHER
ALERT IS IN EFFECT UNTIL 945 PM CDT. THIS SIGNIFICANT WEATHER ALERT
ALSO INCLUDES PIN OAK LAKE.