Alert archive / Mississippi / Flash Flood Watches in 2011

Flash Flood Watch 6, NWS Memphis, TN

April 23, 20118 counties in Mississippi; Lake County, Obion County, Tennessee; 4 counties in Arkansas

NWS Memphis, TN issued this flash flood watch at Apr 23, 2011, 9:31 AM CDT for 8 counties in Mississippi; Lake County, Obion County, Tennessee; 4 counties in Arkansas. It took effect at Apr 23, 2011, 12:00 PM CDT. It was in force for 4 days.

The area

The counties it named.

The facts

Issued
Apr 23, 2011, 9:31 AM CDT (14:31 UTC)
In effect from
Apr 23, 2011, 12:00 PM CDT
Expired
Apr 27, 2011, 6:44 PM CDT
In force
4 days
Issued by
NWS Memphis, TN
Flood severity
None

Counties Clay County, AR, Greene County, AR, Lawrence County, AR, Randolph County, AR, Calhoun County, MS, Chickasaw County, MS, Itawamba County, MS, Lee County, MS, Monroe County, MS, Pontotoc County, MS, Tallahatchie County, MS, Yalobusha County, MS, Lake County, TN, Obion County, TN

The radar

The Memphis radar (KNQA), 45 km from the middle of the area, began a volume at 14:34 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Little Rock, AR (KLZK), launched 12:00Z, 2.5 hours before the alert went out and 37 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Little Rock, AR at 12:00Z on 2011-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1696 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Little Rock, AR at 12:00Z on 2011-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 216 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1696 J/kg
Mixed-layer CIN
-99 J/kg
Mixed-layer LCL
677 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
216 m²/s²
0-3 km storm-relative helicity
243 m²/s²
Significant tornado parameter
1.2
Supercell composite
12.4

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Memphis, TN wrote its last area forecast discussion before this flash flood watch went out at Apr 23, 6:38 AM CDT, 2 hours 53 minutes earlier.

Area forecast discussion, Apr 23, 6:38 AM CDT, 2 hours 53 minutes before
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Hazardous weather outlook, Apr 23, 5:02 AM CDT, 4 hours 29 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MEMPHIS TN
502 AM CDT SAT APR 23 2011

ARZ008-009-017-018-026>028-035-036-048-049-058-MOZ113-115-
MSZ001>017-020>024-TNZ001>004-019>021-048>055-088>092-241215-
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-
502 AM CDT SAT APR 23 2011

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

.DAY ONE...TODAY AND TONIGHT

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS TODAY AND TONIGHT
GENERALLY ALONG AND NORTH OF THE INTERSTATE TO CORRIDOR. THESE
STORMS COULD PRODUCE LARGE HAIL AND DAMAGING WINDS AND SHORT
LIVED TORNADOES.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

A MUCH BETTER CHANCE FOR SEVERE THUNDERSTORMS APPEARS PROBABLE
EARLY NEXT WEEK. TWO STRONG SYSTEMS WILL TRACK NORTH OF THE
MIDSOUTH BETWEEN MONDAY AND WEDNESDAY. DAMAGING WINDS...VERY LARGE
HAIL AND TORNADOES ARE POSSIBLE MONDAY. A GREATER THREAT OF STRONG
LONG TRACKED TORNADOES IS EXPECTED ON WEDNESDAY ALONG WITH
DAMAGING WIND AND LARGE HAIL.

MULTIPLE ROUNDS OF THUNDERSTORMS MONDAY THROUGH WEDNESDAY WILL BRING
SEVERAL INCHES OF RAIN TO THE MIDSOUTH RESULTING IN THE THREAT
FOR FLASH FLOODING. THE HIGHEST THREAT AREA APPEARS TO BE ALONG
AND NORTH OF THE TENNESSEE/MISSISSIPPI STATE LINE AT THIS TIME.

AREA RIVERS WILL RISE THROUGH NEXT WEEK...AND SIGNIFICANT RIVER
FLOODING IS POSSIBLE ON THE MISSISSIPPI BY LATE NEXT WEEK AS HEAVY
RAINFALL UPSTREAM OVER THE NEXT FEW DAYS BEGINS TO WORK ITS WAY
SOUTH.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED NEXT WEEK.

30/SIRMON

The office that day

Everything else NWS Memphis, TN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 23, 3:15 PM CDTSevere Thunderstorm WarningMEGObion, Weakley30 min
Apr 23, 12:34 PM CDTSpecial Weather StatementMEGRandolph41 min
Apr 23, 2:50 PM CDTSpecial Weather StatementMEGRandolph25 min
Apr 23, 3:07 PM CDTSpecial Weather StatementMEGClay23 min
Apr 23, 3:34 PM CDTAreal Flood AdvisoryMEGClay, Greene116 min
Apr 23, 4:30 PM CDTRiver Flood WarningMEGClay, Greene44 days
Apr 23, 4:30 PM CDTRiver Flood WarningMEGSt. Francis39 days

Nearby

Flash Flood Watches in Mississippi, 2011Flash Flood Watches in Arkansas, 2011Flash Flood Watches in Tennessee, 2011Every flash flood watch in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.