Alert archive / Arkansas / Flash Flood Warnings in 2009

Flash Flood Warning 114, NWS Memphis, TN

July 21, 2009Lake County, Tennessee; 8 counties in Arkansas

NWS Memphis, TN issued this flash flood warning at Jul 21, 2009, 11:35 AM CDT for Lake County, Tennessee; 8 counties in Arkansas. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 21, 2009, 11:35 AM CDT (16:35 UTC)
Expired: Jul 21, 2009, 5:30 PM CDT
In force: 6 hr
Issued by: NWS Memphis, TN
Area: Storm-based polygon
Flood severity: None

Counties Craighead County, AR, Crittenden County, AR, Cross County, AR, Lee County, AR, Mississippi County, AR, Phillips County, AR, Poinsett County, AR, St. Francis County, AR, Lake County, TN

The radar

The Memphis radar (KNQA), 55 km from the middle of the area, began a volume at 16:37 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

Springfield, MO (KSGF), launched 12:00Z, 4.6 hours before the alert went out and 344 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 593 J/kg
Mixed-layer CIN: -33 J/kg
Mixed-layer LCL: 590 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 67 m²/s²
0-3 km storm-relative helicity: 84 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning 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 warning went out at Jul 21, 11:07 AM CDT, 28 minutes earlier.

Area forecast discussion, Jul 21, 11:07 AM CDT, 28 minutes before

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Hazardous weather outlook, Jul 21, 10:13 AM CDT, 1 hour 22 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MEMPHIS TN
1013 AM CDT TUE JUL 21 2009

ARZ008-009-017-018-026>028-035-036-048-049-058-MOZ113-115-
MSZ001>017-020>024-TNZ001>004-019>021-048>055-088>092-221100-
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-
1013 AM CDT TUE JUL 21 2009

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 OF SEVERE THUNDERSTORMS FROM PORTIONS OF
EAST-CENTRAL ARKANSAS INTO PORTIONS OF NORTH MISSISSIPPI THIS
AFTERNOON AND EVENING. THE AREA AFFECTED IS GENERALLY ALONG AND TO
THE SOUTH OF A LINE FROM MARIANNA ARKANSAS TO SENATOBIA MISSISSIPPI
TO PITTSBORO MISSISSIPPI. THE BEST TIME FOR SEVERE WEATHER IS
BETWEEN NOON AND MIDNIGHT. DAMAGING WINDS...LARGE HAIL...AND
ISOLATED TORNADOES ARE POSSIBLE. A FEW STRONG THUNDERSTORMS ARE
POSSIBLE ACROSS THE REMAINDER OF NORTH MISSISSIPPI WITH GUSTY
WINDS UP TO 45 MPH AND SMALL HAIL.

A FLASH FLOOD WATCH HAS BEEN ISSUED FOR THE ENTIRE MIDSOUTH
THROUGH TONIGHT. RAINFALL AMOUNTS FROM SHOWERS AND THUNDERSTORMS
BETWEEN 3 AND 5 INCHES...LOCALLY MORE...IS POSSIBLE.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BECOME NECESSARY THIS AFTERNOON AND EVENING
FOR THE SLIGHT RISK AREA. ALSO...SPOTTERS THROUGHOUT THE ENTIRE
MIDSOUTH ARE ENCOURAGED TO RELAY ANY REPORTS OF FLOODING TO THE
NATIONAL WEATHER SERVICE OFFICE IN MEMPHIS.

JCL

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 21, 10:06 AM CDT	Flash Flood Watch	MEG	Alcorn, Benton, Calhoun, Chickasaw, Coahoma, DeSoto and 16 more	17 hr
Jul 21, 1:13 PM CDT	Flash Flood Warning	MEG	Coahoma, DeSoto, Lafayette, Marshall, Panola, Quitman and 4 more	6 hr
Jul 21, 9:52 AM CDT	Flash Flood Warning	MEG	Clay, Craighead, Cross, Greene, Lawrence, Poinsett and 2 more	6 hr

Nearby

Flash Flood Warnings in Arkansas, 2009 Flash Flood Warnings in Tennessee, 2009 Every flash flood warning in 2009

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.