Alert archive / Missouri / Flash Flood Warnings in 2020

Flash Flood Warning 4, NWS St. Louis, MO

April 24, 2020Monroe County, Missouri

NWS St. Louis, MO issued this flash flood warning at Apr 24, 2020, 1:51 PM CDT for Monroe County, Missouri. It was in force for 6 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: Apr 24, 2020, 1:51 PM CDT (18:51 UTC)
Expired: Apr 24, 2020, 7:45 PM CDT
In force: 6 hr
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Flood severity: None

County Monroe County, MO

The radar

The St Louis radar (KLSX), 149 km from the middle of the area, began a volume at 18:54 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

Davenport, (KDVN), launched 12:00Z, 6.9 hours before the alert went out and 261 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 539 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 5 m²/s²
0-3 km storm-relative helicity: 52 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

864 
WGUS53 KLSX 241851
FFWLSX
MOC137-250045-
/O.NEW.KLSX.FF.W.0004.200424T1851Z-200425T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
151 PM CDT Fri Apr 24 2020

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Northern Monroe County in northeastern Missouri...

* Until 745 PM CDT.

* At 150 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to three inches of rain have
  already fallen. Flash flooding is ongoing or expected to begin
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  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...
  Monroe City, Granville, Holliday, Stoutsville and Indian Creek. 

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 3952 9220 3961 9210 3966 9197 3966 9172
      3953 9171 3947 9214

FLASH FLOOD...RADAR INDICATED

$$

Gosselin

1 follow-up statement

340 
WGUS73 KLSX 250045
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
745 PM CDT Fri Apr 24 2020

MOC137-250055-
/O.EXP.KLSX.FF.W.0004.000000T0000Z-200425T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Monroe MO-
745 PM CDT Fri Apr 24 2020

...THE FLASH FLOOD WARNING FOR NORTHERN MONROE COUNTY IN NORTHEASTERN
MISSOURI HAS EXPIRED...

Flood waters have receded. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 3952 9220 3961 9210 3966 9197 3966 9172
      3953 9171 3947 9214

$$

Tilly

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 24, 3:06 AM CDT	Dense Fog Advisory	LSX	Iron, Jefferson, Madison, Reynolds, Sainte Genevieve, Saint Francois and 1 more	6 hr
Apr 24, 1:24 PM CDT	Areal Flood Advisory	LSX	Monroe	3 hr
Apr 24, 2:01 PM CDT	Severe Thunderstorm Warning	LSX	Cole	44 min
Apr 24, 2:41 PM CDT	Severe Thunderstorm Warning	LSX	Monroe, Ralls	49 min

Nearby

Flash Flood Warnings in Missouri, 2020 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.