Alert archive / Missouri / Flash Flood Warnings in 2021
Flash Flood Warning 34, NWS St. Louis, MO
NWS St. Louis, MO issued this flash flood warning at Jul 31, 2021, 7:39 AM CDT for Marion County, Missouri. It was in force for 3 hr. 4 reports 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
- Jul 31, 2021, 7:39 AM CDT (12:39 UTC)
- Expired
- Jul 31, 2021, 10:45 AM CDT
- In force
- 3 hr
- Issued by
- NWS St. Louis, MO
- Area
- Storm-based polygon
- Flood severity
- None
County Marion County, MO
The radar
The St Louis radar (KLSX), 142 km from the middle of the area, began a volume at 12:43 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 |
|---|---|---|---|
| Jul 31, 8:17 AM CDT | FLASH FLOOD | 1 Ene Hannibal, MO | WATER OVER THE ROADWAY AT HIGHWAY 61 AND ROSS IN HANNIBAL, MO. THE ROADWAY IS CLOSED. |
| Jul 31, 9:15 AM CDT | FLASH FLOOD | 1 E Hannibal, MO | WATER OVER THE ROADWAY AT 7TH STREET NEAR WARREN BARRETT IN HANNIBAL, MO. |
| Jul 31, 9:38 AM CDT | FLASH FLOOD | 1 Sse Hannibal, MO | LAW ENFORCEMENT REPORTED FLOODING ON LINDELL/PATCHEN IN HANNIBAL. HIGH WATER HAS ACCUMULATED DEBRIS AGAINST THE BRIDGE NEAR WARREN BARRETT/LINDELL. |
| Jul 31, 10:06 AM CDT | FLASH FLOOD | 2 S Hannibal, MO | WATER OVER THE ROADWAY AT 30TH AND WARREN BARRETT DRIVE. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 0.7 hours before the alert went out and 218 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1355 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 1 m²/s²
- 0-3 km storm-relative helicity
- 123 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
253
WGUS53 KLSX 311239
FFWLSX
MOC127-311545-
/O.NEW.KLSX.FF.W.0034.210731T1239Z-210731T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
739 AM CDT Sat Jul 31 2021
The National Weather Service in St Louis has issued a
* Flash Flood Warning for...
Marion County in northeastern Missouri...
* Until 1045 AM CDT.
* At 739 AM CDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Two to three inches have fallen
already. 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...
Hannibal, Palmyra, Warren, Philadelphia and Taylor.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3969 9148 3978 9184 3995 9184 3995 9144
3992 9142 3988 9145 3984 9144 3980 9137
3973 9137 3968 9132
FLASH FLOOD...RADAR INDICATED
$$
KD2 follow-up statements
022
WGUS73 KLSX 311315
FFSLSX
Flash Flood Statement
National Weather Service St Louis MO
815 AM CDT Sat Jul 31 2021
MOC127-311545-
/O.CON.KLSX.FF.W.0034.000000T0000Z-210731T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Marion MO-
815 AM CDT Sat Jul 31 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1045 AM CDT THIS
MORNING FOR MARION COUNTY IN NORTHEASTERN MISSOURI...
At 815 AM CDT, local law enforcement reported roadways in Hannibal
were under water. Between 2 and 4 inches of rain have fallen. Flash
flooding is ongoing.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Law enforcement reported.
IMPACT...Flash flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other poor
drainage and low-lying areas.
Some locations that will experience flash flooding include...
Hannibal, Palmyra, Warren, Philadelphia and Taylor.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3969 9148 3978 9184 3995 9184 3995 9144
3992 9142 3988 9145 3984 9144 3980 9137
3973 9137 3968 9132
FLASH FLOOD...OBSERVED
$$
KD520
WGUS73 KLSX 311541
FFSLSX
Flash Flood Statement
National Weather Service St Louis MO
1041 AM CDT Sat Jul 31 2021
MOC127-311551-
/O.EXP.KLSX.FF.W.0034.000000T0000Z-210731T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Marion MO-
1041 AM CDT Sat Jul 31 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 1045 AM CDT THIS MORNING FOR
MARION COUNTY IN NORTHEASTERN MISSOURI...
Flood waters continue to recede. The heavy rain has ended. Please
continue to heed remaining road closures.
LAT...LON 3969 9148 3978 9184 3995 9184 3995 9144
3992 9142 3988 9145 3984 9144 3980 9137
3973 9137 3968 9132
$$
KDThe office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 31, 5:34 AM CDT | Areal Flood Advisory | LSX | Knox, Lewis | 3 hr |
| Jul 31, 6:51 AM CDT | Areal Flood Advisory | LSX | Marion, Shelby | 3 hr |
| Jul 31, 9:49 AM CDT | River Flood Warning | LSX | Marion | 18 hr |
| Jul 31, 9:50 AM CDT | River Flood Warning | LSX | Marion | 3 days |
| Jul 31, 3:05 PM CDT | River Flood Warning | LSX | Lewis | 49 hr |
| Jul 31, 5:15 PM CDT | Severe Thunderstorm Warning | LSX | Iron, Reynolds | 21 min |
Nearby
Flash Flood Warnings in Missouri, 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.