Flash Flood Warning 35, NWS Memphis, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEMPHIS TN
807 PM CDT TUE MAY 21 2013

.UPDATE...

A LINE OF SHOWERS AND THUNDERSTORMS CONTINUES TO MOVE EAST ACROSS
WEST TENNESSEE AND NORTH MISSISSIPPI. THE ATMOSPHERE ACROSS WEST
TENNESSEE HAS BEEN WORKED OVER AND THUS FAR THE STORMS HAVE NOT
APPROACHED SEVERE LIMITS. MEANWHILE FURTHER SOUTH...THE LINE IS
JUST GETTING INTO NORTHEAST MISSISSIPPI WHERE THE ATMOSPHERE IS
MUCH MORE UNSTABLE SINCE NO RAIN HAS FALLEN ACROSS THE AREA TODAY.
IN ADDITION...THE SECOND LINE OF SHOWERS AND THUNDERSTORMS
ASSOCIATED WITH THE UPPER SHORTWAVE IS BEGINNING TO TO STREAM
NORTHWARD ACROSS SOUTHEAST ARKANSAS. DON/T KNOW WHAT THE STORMS
WILL DO WHEN THEY MOVE INTO NORTHWEST MISSISSIPPI AS THE
ATMOSPHERE HAS BEEN WORKED OVER FROM FIRST LINE. HOWEVER...SEVERE
THUNDERSTORM WARNINGS CONTINUE TO BE ISSUED ALONG PORTIONS OF THE
LINE SO WILL HANG ON TO THE WATCH FOR NORTH MISSISSIPPI AFTER THE
FIRST LINE MOVES THROUGH UNTIL WE SEE WHAT THE STORMS DO ALONG THE
SECOND LINE. HOWEVER...WILL CONTINUE TO CLEAR THE WATCH BEHIND THE
FIRST LINE ACROSS WEST TENNESSEE.

KRM

&&

.DISCUSSION... /ISSUED 304 PM CDT TUE MAY 21 2013/

VERY ACTIVE RADAR THIS AFTERNOON. OVERNIGHT/EARLY MORNING
CONVECTION MAY HAVE US FROM A MUCH MORE SIGNIFICANT SEVERE WEATHER
OUTBREAK TODAY...ALTHOUGH SEVERE POTENTIAL STILL
EXISTS...ESPECIALLY ACROSS NORTH MISSISSIPPI. FARTHER NORTH THE
AIRMASS HAS BEEN WORKED OVER...AND ABUNDANT CLOUD COVER HAS KEPT
TEMPERATURES QUITE A BIT COOLER. INSTABILITY IS HIGHEST IN NORTH
MISSISSIPPI WHERE TEMPERATURES HAVE BEEN ABLE TO CLIMB INTO THE
MIDDLE AND UPPER 80S. DEW POINTS ARE IN THE UPPER 60S TO LOWER 70S
RESULTING IN CAPES IN EXCESS OF 2500 J/KG AND LI'S BELOW -6C. JUST
ACROSS THE STATE LINE IN MOST OF TN...THE MISSOURI BOOTHEEL AND
NORTHEAST ARKANSAS...CAPES ARE GENERALLY BELOW 1500 J/KG WITH LI'S
-4C OR GREATER. DEW POINTS ARE ALSO SLIGHTLY HIGHER. IN THE PAST
COUPLE OF HOURS STORMS HAVE DEVELOPED IN NORTH MISSISSIPPI AND
HAVE SHOWN SOME SIGNS OF ROTATION. 0-3KM HELICITY IS GENERALLY
50-90M^2/S^2 WHICH WOULD CERTAINLY SUPPORT ROTATING STORMS. UPPER
LEVEL SUPPORT IS NOT CURRENTLY AS FAVORABLE FOR SEVERE
THUNDERSTORMS...ALTHOUGH BETTER SUPPORT IS EXPECTED TO MOVE IN
TONIGHT.

ANOTHER ROUND OF STORMS CAN BE SEEN OVER NORTH TEXAS INTO
OKLAHOMA. THIS LINE WILL BRING ADDITIONAL SHOWERS AND
THUNDERSTORMS TO THE MIDSOUTH OVERNIGHT. NUMEROUS OUTFLOW
BOUNDARIES WILL ONLY HELP SUPPORT FOCUS UPDRAFTS AND MAINTAIN A
SEVERE THREAT.

A SHORTWAVE TROUGH CURRENTLY OVER THE TEXAS AND OKLAHOMA
PANHANDLES WILL SHIFT TO THE EAST THIS EVENING AND APPROACH THE
MISSISSIPPI RIVER BY SUNRISE. A SURFACE LOW HAS DEVELOPED OVER
NORTH TEXAS AND SHOULD TRACK NORTHEAST ACROSS CENTRAL ARKANSAS
DURING THE NIGHT. WE WILL SEE A 40-45KT LLJ DEVELOP BY MIDNIGHT
AND MUCH OF THE MIDSOUTH WILL BE IN THE RIGHT ENTRANCE REGION OF A
70-80KT UPPER LEVEL JET. THIS ADDITIONAL DYNAMIC SUPPORT WILL MOVE
IN JUST AS WE LOSE DAYTIME THERMODYNAMIC SUPPORT. THUS FEEL LIKE
THE THREAT FOR SEVERE WEATHER WILL REMAIN ABOUT THE SAME DURING
THE NIGHT...MARGINAL BUT CERTAINLY NOT ZERO.

RESEARCHERS AT MISSISSIPPI STATE UNIVERSITY LAUNCHED A WEATHER
BALLOON MIDDAY ABOUT 30 MILES SOUTHWEST OF GREENWOOD MISSISSIPPI.
IT SHOWS A BIT OF A CAP AT 10KFT...BUT CAPE IN EXCESS OF 3500
J/KG. FARTHER NORTH AT LITTLE ROCK A MIDDAY SOUNDING WAS
INDICATIVE OF A WORKED OVER ENVIRONMENT...FEATURING ONLY 343
JOULES OF CAPE. ANY THREATS FROM STORMS IN WEST TENNESSEE AND EAST
ARKANSAS WOULD BE PRIMARILY HAIL.

A COLD FRONT WILL SWEEP ACROSS THE MIDSOUTH TOMORROW BRINGING AN
END TO THE PRECIPITATION. THE FRONT SHOULD MOVE INTO EAST ARKANSAS
BY 10 AM...CROSS THE MISSISSIPPI RIVER MIDDAY AND EXIT INTO
CENTRAL TENNESSEE/NORTH ALABAMA DURING THE MID AFTERNOON HOURS.
RAIN WILL LIKELY LIMIT TEMPERATURES AGAIN TOMORROW BUT AS RAIN
ENDS...WE COULD SEE TEMPERATURES SURGE INTO THE LOW 80S DURING THE
AFTERNOON HOURS. THE DIURNAL TEMPERATURE PROFILE WILL LIKELY BE
TRICKY TOMORROW DUE THE RAINFALL AND FRONT.

THURSDAY THROUGH THE WEEKEND LOOK MOSTLY DRY. TEMPERATURES THURSDAY
WILL BE NEAR NORMAL...WITH COOLISH FRIDAY...THEN TRENDING
GRADUALLY WARMER THROUGH THE WEEKEND. FRIDAY THROUGH THE WEEKEND
OUR WEATHER SHOULD BE PRIMARILY INFLUENCED BY A WEAK RIDGE ALOFT
AND SURFACE HIGH PRESSURE RESULTING IN DRY CONDITIONS.

&&

.AVIATION...
00Z TAF CYCLE

ONGOING LINE OF THUNDERSTORMS WILL MOVE EAST OF THE MIDSOUTH..LEAVING
MAINLY STRATIFORM RAIN WITH SOME EMBEDDED THUNDERSTORMS MOVING
THROUGH THE REGION OVERNIGHT. CEILINGS SHOULD REMAIN ABOVE 2000FT
AT ALL SITES. EXPECT CONDITIONS TO SLOWLY IMPROVE THRU MIDMORNING
TOMORROW.

SAK

&&

&&

.PRELIMINARY POINT TEMPS/POPS...
MEM  69  83  61  82 / 100  60  10  10
MKL  67  81  58  81 / 100  60  10  10
JBR  65  82  57  80 / 100  40  10  10
TUP  67  83  60  86 / 100  70  10  10

&&

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

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MEMPHIS TN
318 PM CDT TUE MAY 21 2013

ARZ008-009-017-018-026>028-035-036-048-049-058-MOZ113-115-
MSZ001>017-020>024-TNZ001>004-019>021-048>055-088>092-222230-
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-
318 PM CDT TUE MAY 21 2013

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS ACROSS THE ENTIRE
MID SOUTH TODAY AND TONIGHT. MULTIPLE ROUNDS OF STRONG TO SEVERE
THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND OVERNIGHT AS A
STRONG AREA OF LOW PRESSURE MOVES INTO THE LOWER MISSISSIPPI
VALLEY. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE
WEATHER THREATS ALONG WITH A SECONDARY POTENTIAL FOR PERHAPS A
TORNADO. LOCALIZED FLASH FLOODING FROM HEAVY RAINFALL WILL ALSO BE
POSSIBLE.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THE PROBABILITY OF WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGERS MAY BE NEEDED IN
SUPPORT OF SEVERE WEATHER OPERATIONS TODAY AND TONIGHT.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEMPHIS TN
506 PM CDT TUE MAY 21 2013

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

0435 PM     FLASH FLOOD      HORN LAKE               34.96N 90.04W
05/21/2013                   DESOTO             MS   PUBLIC

            INTERSECTION OF NAIL ROAD AND TWIN LAKES COMPLETELY
            FLOODED.

0459 PM     FLASH FLOOD      SOUTHAVEN               34.97N 90.00W
05/21/2013                   DESOTO             MS   TRAINED SPOTTER

            WATER OVER RASCO ROAD EAST OF HWY 51. ALSO PEA SIZE HAIL.

&&

ZEI

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE MEMPHIS TN
508 PM CDT TUE MAY 21 2013

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

0314 PM     FUNNEL CLOUD     TRUMANN                 35.67N 90.52W
05/21/2013                   POINSETT           AR   PUBLIC

0343 PM     HAIL             3 NE TRUMANN            35.71N 90.48W
05/21/2013  E1.00 INCH       CRAIGHEAD          AR   TRAINED SPOTTER

0355 PM     HAIL             MARKED TREE             35.53N 90.42W
05/21/2013  E0.50 INCH       POINSETT           AR   PUBLIC

            PUBLIC REPORTS DIME SIZE HAIL.

0435 PM     FLASH FLOOD      HORN LAKE               34.96N 90.04W
05/21/2013                   DESOTO             MS   PUBLIC

            INTERSECTION OF NAIL ROAD AND TWIN LAKES COMPLETELY
            FLOODED.

0459 PM     FLASH FLOOD      SOUTHAVEN               34.97N 90.00W
05/21/2013                   DESOTO             MS   TRAINED SPOTTER

            WATER OVER RASCO ROAD EAST OF HWY 51. ALSO PEA SIZE HAIL.

&&

ZEI

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEMPHIS TN
534 PM CDT TUE MAY 21 2013

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

0521 PM     FLASH FLOOD      HORN LAKE               34.96N 90.04W
05/21/2013                   DESOTO             MS   BROADCAST MEDIA

            LAW ENFORCEMENT CLOSED US HWY51 JUST SOUTH OF STATELINE
            ROAD.

&&

ZEI

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEMPHIS TN
557 PM CDT TUE MAY 21 2013

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

0537 PM     FLASH FLOOD      HORN LAKE               34.96N 90.04W
05/21/2013                   DESOTO             MS   BROADCAST MEDIA

            NUMEROUS HOMES REPORT FLOODING IN DESOTO VILLAGE. UP TO
            TWO FEET DEEP IN PLACES.

0542 PM     HAIL             3 N COLLIERVILLE        35.10N 89.68W
05/21/2013  E1.00 INCH       SHELBY             TN   PUBLIC

            QUARTER SIZE HAIL COLLIERVILLE-ARLINGTON AND RALEIGH
            LAGRANGE.

&&

ZEI

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEMPHIS TN
637 PM CDT TUE MAY 21 2013

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

0604 PM     FLASH FLOOD      3 ENE ARLINGTON         35.30N 89.62W
05/21/2013                   FAYETTE            TN   TRAINED SPOTTER

            STATE HWY 196 AT ORR RD COVERD BY WATER.

0604 PM     FLASH FLOOD      OLIVE BRANCH            34.95N 89.83W
05/21/2013                   DESOTO             MS   TRAINED SPOTTER

            HOMES AND BUSINESSES ON GOODMAN NEAR MALONE FLOODED WITH
            UP TO 3 FEET OF WATER.

0615 PM     FLASH FLOOD      DOWNTOWN MEMPHIS        35.13N 90.05W
05/21/2013                   SHELBY             TN   BROADCAST MEDIA

            I-55 NORTH AFTER 3RD CLSED DUE TO FLOODING.

&&

ZEI

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEMPHIS TN
650 PM CDT TUE MAY 21 2013

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

0630 PM     FLASH FLOOD      HORN LAKE               34.96N 90.04W
05/21/2013                   DESOTO             MS   STORM CHASER

            MAJOR FLASH FLOODING ACROSS SOUTHAVEN AND HORN LAKE WITH
            MANY ROADS IMPASSABLE. RAIN GAUGE MEASURED 4.29INCHES AT
            CHASERS HOME LOCATION OVER A PERIOD OF FOUR HOURS.

&&

ZEI