Alert archive / Missouri / Flash Flood Warnings in 2021

Flash Flood Warning 22, NWS St. Louis, MO

July 1, 2021Marion County, Shelby County, Missouri

NWS St. Louis, MO issued this flash flood warning at Jul 1, 2021, 12:35 AM CDT for Marion County, Shelby County, Missouri. It was in force for 3 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
Jul 1, 2021, 12:35 AM CDT (05:35 UTC)
Expired
Jul 1, 2021, 3:21 AM CDT
In force
3 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

Counties Marion County, MO, Shelby County, MO

The radar

The St Louis radar (KLSX), 156 km from the middle of the area, began a volume at 05:36 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 00:00Z, 5.6 hours before the alert went out and 241 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-pSkew-T log-p diagram, Davenport, at 00:00Z on 2021-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 38 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 2021-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 6 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
38 J/kg
Mixed-layer CIN
-40 J/kg
Mixed-layer LCL
1480 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
6 m²/s²
0-3 km storm-relative helicity
33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

629 
WGUS53 KLSX 010535
FFWLSX
MOC127-205-010830-
/O.NEW.KLSX.FF.W.0022.210701T0535Z-210701T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
1235 AM CDT Thu Jul 1 2021

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Southwestern Marion County in northeastern Missouri...
  Central Shelby County in northeastern Missouri...

* Until 330 AM CDT.

* At 1235 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1.5 and 2.5 inches of 
  rain have fallen. Additional rainfall amounts of 1 to 2 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...
  Shelbina and Warren.

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.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3981 9216 3977 9169 3969 9171 3969 9172
      3968 9172 3971 9218

FLASH FLOOD...RADAR INDICATED

$$

BRC
1 follow-up statement
924 
WGUS73 KLSX 010821
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
321 AM CDT Thu Jul 1 2021

MOC127-205-010831-
/O.CAN.KLSX.FF.W.0022.000000T0000Z-210701T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Marion MO-Shelby MO-
321 AM CDT Thu Jul 1 2021

...FLASH FLOOD WARNING FOR SOUTHWESTERN MARION AND CENTRAL SHELBY 
COUNTIES IN NORTHEASTERN MISSOURI HAS BEEN REPLACED WITH A FLOOD 
ADVISORY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

A Flash Flood Watch remains in effect until 700 AM CDT for Portions 
of central, east central, and northeast Missouri.

LAT...LON 3981 9216 3977 9169 3969 9171 3969 9172
      3968 9172 3971 9218

$$

BRC

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 30, 8:41 PM CDTAreal Flood AdvisoryLSXSaint Charles3 hr
Jun 30, 10:44 PM CDTAreal Flood AdvisoryLSXMonroe, Ralls7 hr
Jul 1, 12:12 AM CDTAreal Flood AdvisoryLSXMarion, Shelby23 min
Jul 1, 2:57 AM CDTAreal Flood AdvisoryLSXMarion, Monroe, Shelby3 hr
Jul 1, 3:21 AM CDTAreal Flood AdvisoryLSXMarion, Shelby2 hr
Jul 1, 5:16 AM CDTAreal Flood AdvisoryLSXCallaway, Montgomery, Warren3 hr
Jul 1, 5:51 AM CDTAreal Flood AdvisoryLSXSaint Charles3 hr
Jul 1, 6:04 AM CDTAreal Flood AdvisoryLSXBoone, Callaway, Cole, Moniteau28 min
Jul 1, 6:32 AM CDTFlash Flood WarningLSXBoone, Callaway, Cole, Moniteau3 hr
Jul 1, 6:59 AM CDTRiver Flood WarningLSXMonroe37 hr
Jul 1, 8:21 AM CDTRiver Flood WarningLSXCole32 hr
Jul 1, 11:54 AM CDTRiver Flood WarningLSXLincoln27 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.