Alert archive / Mississippi / Flash Flood Warnings in 2021

Flash Flood Warning 86, NWS Jackson, MS

August 30, 2021Copiah County, Simpson County, Mississippi

NWS Jackson, MS issued this flash flood warning at Aug 30, 2021, 6:41 AM CDT for Copiah County, Simpson County, Mississippi. It was in force for 4 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 30, 2021, 6:41 AM CDT (11:41 UTC)
Expired
Aug 30, 2021, 10:45 AM CDT
In force
4 hr
Issued by
NWS Jackson, MS
Area
Storm-based polygon
Flood severity
None

Counties Copiah County, MS, Simpson County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 63 km from the middle of the area, began a volume at 11:46 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.

What was reported inside it

TimeReportWhereRemark
Aug 30, 9:23 AM CDTFLASH FLOODMagee, MSSOCIAL MEDIA PICTURE OF STREET FLOODING IN MAGEE, OVER 4 INCHES OF RAIN WAS ALSO REPORTED.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 11.7 hours before the alert went out and 63 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, Jackson, MS at 00:00Z on 2021-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 91 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, Jackson, MS at 00:00Z on 2021-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 226 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
91 J/kg
Mixed-layer CIN
-62 J/kg
Mixed-layer LCL
697 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
226 m²/s²
0-3 km storm-relative helicity
209 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

243 
WGUS54 KJAN 301141
FFWJAN
MSC029-127-301545-
/O.NEW.KJAN.FF.W.0086.210830T1141Z-210830T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Jackson MS
641 AM CDT Mon Aug 30 2021

The National Weather Service in Jackson has issued a

* Flash Flood Warning for...
  Copiah County in central Mississippi...
  Simpson County in central Mississippi...

* Until 1045 AM CDT.

* At 641 AM CDT, Doppler radar indicated heavy rain across the 
  warned area. Between 2 and 4 inches of rain have fallen. The 
  expected rainfall rate is 1 to 2 inches in 1 hour. Additional 
  rainfall amounts of 2 to 3 inches are possible in the warned area. 
  Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Crystal Springs, Magee, Hazlehurst, Mendenhall, Pinola, Union, 
  Wesson, Hopewell, Rockport, Harrisville, Shivers, Gallman, 
  Martinsville, Glancy, Sanatorium, Martinville, Barlow, Allen, 
  Pleasant Hill and D'Lo.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3182 9074 3205 9039 3205 8966 3178 8965
      3176 9013 3170 9026 3170 9038 3169 9038
      3169 9041 3170 9041 3170 9074

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

TW
2 follow-up statements
493 
WGUS74 KJAN 301518
FFSJAN

Flash Flood Statement
National Weather Service Jackson MS
Issued by National Weather Service Shreveport LA
1018 AM CDT Mon Aug 30 2021

MSC029-127-301545-
/O.CON.KJAN.FF.W.0086.000000T0000Z-210830T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Copiah MS-Simpson MS-
1018 AM CDT Mon Aug 30 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1045 AM CDT THIS 
MORNING FOR COPIAH AND SIMPSON COUNTIES...

At 1018 AM CDT, Doppler radar indicated heavy rain across the warned 
area. Between 2 and 4 inches of rain have fallen. The expected 
rainfall rate is 1 to 2 inches in 1 hour. Additional rainfall 
amounts of 2 to 3 inches are possible in the warned area. Flash 
flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Crystal Springs, Magee, Hazlehurst, Mendenhall, Pinola, Union, 
  Wesson, Hopewell, Rockport, Harrisville, Shivers, Gallman, 
  Martinsville, Glancy, Sanatorium, Martinville, Barlow, Allen, 
  Pleasant Hill and D'Lo.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3182 9074 3204 9039 3204 8966 3178 8965
      3176 9013 3170 9026 3170 9038 3169 9038
      3169 9041 3170 9041 3170 9074

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

13
943 
WGUS74 KJAN 301546
FFSJAN

Flash Flood Statement
National Weather Service Jackson MS
Issued by National Weather Service Shreveport LA
1046 AM CDT Mon Aug 30 2021

MSC029-127-301556-
/O.EXP.KJAN.FF.W.0086.000000T0000Z-210830T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Copiah MS-Simpson MS-
1046 AM CDT Mon Aug 30 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR COPIAH AND SIMPSON COUNTIES...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 3182 9073 3204 9039 3204 8966 3178 8965
      3176 9013 3170 9026 3169 9038 3170 9074

$$

The office that day

Everything else NWS Jackson, MS issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 30, 3:32 AM CDTFlash Flood WarningJANForrest, Lamar, Marion6 hr
Aug 30, 5:35 AM CDTFlash Flood WarningJANLawrence, Lincoln3 hr
Aug 30, 6:00 AM CDTFlash Flood WarningJANCovington, Jefferson Davis4 hr
Aug 30, 7:08 AM CDTFlash Flood WarningJANJones4 hr
Aug 30, 8:14 AM CDTFlash Flood WarningJANRankin, Smith4 hr
Aug 30, 8:21 AM CDTFlash Flood WarningJANRankin, Smith4 hr
Aug 30, 8:33 AM CDTFlash Flood WarningJANCovington, Hinds, Jasper, Jones, Rankin, Scott and 2 more4 hr
Aug 30, 12:38 PM CDTSpecial Weather StatementJANMadison22 min
Aug 30, 3:17 PM CDTFlash Flood WarningJANLauderdale118 min
Aug 30, 4:33 PM CDTFlash Flood WarningJANKemper, Noxubee2 hr
Aug 30, 5:01 PM CDTFlash Flood WarningJANClarke, Lauderdale3 hr

Nearby

Flash Flood Warnings in Mississippi, 2021Every flash flood warning in 2021

Sources

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