Alert archive / Mississippi / Flash Flood Warnings in 2021

Flash Flood Warning 89, NWS Jackson, MS

August 30, 2021Rankin County, Smith County, Mississippi

NWS Jackson, MS issued this flash flood warning at Aug 30, 2021, 8:21 AM CDT for Rankin County, Smith 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, 8:21 AM CDT (13:21 UTC)
Expired: Aug 30, 2021, 12:15 PM CDT
In force: 4 hr
Issued by: NWS Jackson, MS
Area: Storm-based polygon
Flood severity: None

Counties Rankin County, MS, Smith County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 22 km from the middle of the area, began a volume at 13:22 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

Time	Report	Where	Remark
Aug 30, 12:00 PM CDT	FLASH FLOOD	3 Nnw Burns, MS	FLOODING CAUSED A WASHOUT ON SMITH CO RD 559.

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 12:00Z, 1.4 hours before the alert went out and 29 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: 49 J/kg
Mixed-layer CIN: -7 J/kg
Mixed-layer LCL: 463 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 387 m²/s²
0-3 km storm-relative helicity: 547 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

118 
WGUS54 KJAN 301321
FFWJAN
MSC121-129-301715-
/O.NEW.KJAN.FF.W.0089.210830T1321Z-210830T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Jackson has issued a

* Flash Flood Warning for...
  Southern Rankin County in central Mississippi...
  Smith County in central Mississippi...

* Until 1215 PM CDT.

* At 821 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 5 inches of rain 
  have fallen. 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 thunderstorms.

  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...
  Jackson, Star, Florence, Raleigh, Taylorsville, White Oak, Burns, 
  Johns, Center Ridge, Cato, Pineville, Piney Woods, Monterey, 
  Whites, Polkville, Mize, Puckett and Sylvarena.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3218 9021 3223 8974 3222 8932 3180 8932
      3178 8965 3205 8966 3205 9023 3209 9023
      3209 9025 3215 9025 3218 9024

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

$$

TW

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 30, 3:32 AM CDT	Flash Flood Warning	JAN	Forrest, Lamar, Marion	6 hr
Aug 30, 5:35 AM CDT	Flash Flood Warning	JAN	Lawrence, Lincoln	3 hr
Aug 30, 6:00 AM CDT	Flash Flood Warning	JAN	Covington, Jefferson Davis	4 hr
Aug 30, 6:41 AM CDT	Flash Flood Warning	JAN	Copiah, Simpson	4 hr
Aug 30, 7:08 AM CDT	Flash Flood Warning	JAN	Jones	4 hr
Aug 30, 8:14 AM CDT	Flash Flood Warning	JAN	Rankin, Smith	4 hr
Aug 30, 8:33 AM CDT	Flash Flood Warning	JAN	Covington, Hinds, Jasper, Jones, Rankin, Scott and 2 more	4 hr
Aug 30, 12:38 PM CDT	Special Weather Statement	JAN	Madison	22 min
Aug 30, 3:17 PM CDT	Flash Flood Warning	JAN	Lauderdale	118 min
Aug 30, 4:33 PM CDT	Flash Flood Warning	JAN	Kemper, Noxubee	2 hr
Aug 30, 5:01 PM CDT	Flash Flood Warning	JAN	Clarke, Lauderdale	3 hr

Nearby

Flash Flood Warnings in Mississippi, 2021 Every 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.