Alert archive / Missouri / Flash Flood Warnings in 2020
Flash Flood Warning 47, NWS St. Louis, MO
NWS St. Louis, MO issued this flash flood warning at Jul 31, 2020, 8:33 AM CDT for Gasconade County, Missouri. It was in force for 6 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
- Jul 31, 2020, 8:33 AM CDT (13:33 UTC)
- Expired
- Jul 31, 2020, 2:30 PM CDT
- In force
- 6 hr
- Issued by
- NWS St. Louis, MO
- Area
- Storm-based polygon
- Flood severity
- None
County Gasconade County, MO
The radar
The St Louis radar (KLSX), 77 km from the middle of the area, began a volume at 13:33 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, 10:38 AM CDT | FLOOD | Gasconade, MO | HIGHWAY 100 IN GASCONADE IS CLOSED BOTH WAYS DUE TO HIGH WATER. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Springfield, MO (KSGF), launched 12:00Z, 1.6 hours before the alert went out and 279 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
- 590 J/kg
- Mixed-layer CIN
- -6 J/kg
- Mixed-layer LCL
- 484 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 10 m²/s²
- 0-3 km storm-relative helicity
- 25 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
170
WGUS53 KLSX 311333
FFWLSX
MOC073-311930-
/O.NEW.KLSX.FF.W.0047.200731T1333Z-200731T1930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
833 AM CDT Fri Jul 31 2020
The National Weather Service in St Louis has issued a
* Flash Flood Warning for...
Northwestern Gasconade County in east central Missouri...
* Until 230 PM CDT.
* At 832 AM CDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Up to three inches of rain have
already fallen and heavy rain continues. Flash flooding is ongoing
or expected to begin shortly.
HAZARD...Flash flooding caused by heavy showers.
SOURCE...Radar indicated.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other
drainage and low lying areas.
* Some locations that will experience flooding include...
Gasconade and Morrison.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.
&&
LAT...LON 3870 9162 3868 9159 3868 9155 3869 9151
3871 9149 3871 9147 3861 9152 3861 9164
3870 9164
FLASH FLOOD...RADAR INDICATED
$$
KD1 follow-up statement
726
WGUS73 KLSX 311542
FFSLSX
Flash Flood Statement
National Weather Service St Louis MO
1042 AM CDT Fri Jul 31 2020
MOC073-311930-
/O.CON.KLSX.FF.W.0047.000000T0000Z-200731T1930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gasconade MO-
1042 AM CDT Fri Jul 31 2020
...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 230 PM CDT FOR
NORTHWESTERN GASCONADE COUNTY...
At 1040 AM CDT, law enforcement and the Missouri Department of
Transportation reported Highway 100 was closed in northern Gasconade
County due to flooding. Up to four inches of rain have already
fallen this morning, with additional rainfall continuing. Flash
flooding is already occurring.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Law enforcement and MODoT.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other drainage
and low lying areas.
Some locations that will experience flooding include...
Gasconade and Morrison.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.
&&
LAT...LON 3870 9162 3868 9159 3868 9155 3869 9151
3871 9149 3871 9147 3861 9152 3861 9164
3870 9164
FLASH FLOOD...OBSERVED
$$
KDThe office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 30, 8:52 PM CDT | Flash Flood Warning | LSX | Cole, Osage | 4 hr |
| Jul 31, 3:25 AM CDT | Flash Flood Watch | LSX | Crawford, Franklin, Iron, Jefferson, Lincoln, Madison and 8 more | 21 hr |
| Jul 31, 7:28 AM CDT | Areal Flood Advisory | LSX | Boone, Callaway, Cole, Gasconade, Moniteau, Montgomery and 1 more | 3 hr |
| Jul 31, 11:31 AM CDT | Areal Flood Advisory | LSX | Franklin, Gasconade, Montgomery, Warren | 3 hr |
| Jul 31, 12:10 PM CDT | Flash Flood Warning | LSX | Franklin, Gasconade, Montgomery, Warren | 6 hr |
| Jul 31, 1:19 PM CDT | Flash Flood Warning | LSX | Franklin, Gasconade, Warren | 6 hr |
| Jul 31, 4:18 PM CDT | Flash Flood Warning | LSX | Iron, Reynolds | 5 hr |
| Jul 31, 4:29 PM CDT | Areal Flood Advisory | LSX | Saint Charles | 3 hr |
Nearby
Flash Flood Warnings in Missouri, 2020Every flash flood warning in 2020
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.