Alert archive / Missouri / Flash Flood Warnings in 2021
Flash Flood Warning 7, NWS St. Louis, MO
NWS St. Louis, MO issued this flash flood warning at Jun 20, 2021, 1:39 AM CDT for Boone County, Missouri. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Jun 20, 2021, 1:39 AM CDT (06:39 UTC)
- Expired
- Jun 20, 2021, 6:34 AM CDT
- In force
- 5 hr
- Issued by
- NWS St. Louis, MO
- Area
- Storm-based polygon
- Flood severity
- None
County Boone County, MO
The radar
The Pleasant Hill radar (KEAX), 156 km from the middle of the area, began a volume at 06:43 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.
The nearest sounding before it
Springfield, MO (KSGF), launched 00:00Z, 6.7 hours before the alert went out and 256 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
- 1685 J/kg
- Mixed-layer CIN
- -99 J/kg
- Mixed-layer LCL
- 1459 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 37 m²/s²
- 0-3 km storm-relative helicity
- 116 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 1.0
The text
As transmitted.
854
WGUS53 KLSX 200639
FFWLSX
MOC019-201230-
/O.NEW.KLSX.FF.W.0007.210620T0639Z-210620T1230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
139 AM CDT Sun Jun 20 2021
The National Weather Service in St Louis has issued a
* Flash Flood Warning for...
Central Boone County in central Missouri...
* Until 730 AM CDT.
* At 139 AM CDT, local law enforcement reported thunderstorms
producing heavy rain near the intersection of West Nifong
Boulevard and Bethel Street in Columbia, Missouri. Between 2 and 3
inches of rain have fallen. Additional rainfall amounts up to 1
inch are possible in the warned area. Flash flooding is already
occurring.
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...
Columbia, Rocheport, Midway and McBaine.
This includes the following State Parks...
Rock Bridge State Park and Jewell Cemetery Historic Site.
This includes the following highways...
Interstate 70 in Missouri between exits 115 and 133.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3906 9253 3900 9218 3883 9218 3885 9244
3889 9248 3890 9247 3891 9248 3892 9250
3894 9251 3895 9254 3898 9256 3898 9257
3899 9256 3900 9256
FLASH FLOOD...OBSERVED
EXPECTED RAINFALL...2-3 INCHES IN 1 HOUR
$$
MRM1 follow-up statement
957
WGUS73 KLSX 201134
FFSLSX
Flash Flood Statement
National Weather Service St Louis MO
634 AM CDT Sun Jun 20 2021
MOC019-201144-
/O.CAN.KLSX.FF.W.0007.000000T0000Z-210620T1230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Boone MO-
634 AM CDT Sun Jun 20 2021
...FLASH FLOOD WARNING IS CANCELLED FOR CENTRAL BOONE COUNTY...
Flood waters have receded. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
LAT...LON 3906 9253 3900 9218 3883 9218 3885 9244
3889 9248 3890 9247 3891 9248 3892 9250
3894 9251 3895 9254 3898 9256 3898 9257
3899 9256 3900 9256
$$
MRMThe office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 19, 7:12 PM CDT | Severe Thunderstorm Warning | LSX | Lincoln, Pike | 48 min |
| Jun 19, 7:31 PM CDT | Severe Thunderstorm Warning | LSX | Lincoln, Saint Charles | 44 min |
| Jun 19, 8:00 PM CDT | Severe Thunderstorm Warning | LSX | Franklin, Saint Charles, Saint Louis | 21 min |
| Jun 19, 8:42 PM CDT | Flash Flood Warning | LSX | Audrain, Boone, Monroe | 6 hr |
| Jun 19, 9:33 PM CDT | Severe Thunderstorm Warning | LSX | Callaway | 42 min |
| Jun 19, 11:49 PM CDT | Areal Flood Warning | LSX | Marion, Pike, Ralls | 11 hr |
| Jun 20, 2:13 AM CDT | Areal Flood Warning | LSX | Audrain, Boone, Monroe | 3 hr |
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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.