Alert archive / Missouri / Flash Flood Warnings in 2017

Flash Flood Warning 20, NWS St. Louis, MO

August 22, 2017Shelby County, Missouri

NWS St. Louis, MO issued this flash flood warning at Aug 22, 2017, 12:47 AM CDT for Shelby County, Missouri. It was in force for 8 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
Aug 22, 2017, 12:47 AM CDT (05:47 UTC)
Expired
Aug 22, 2017, 8:45 AM CDT
In force
8 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

County Shelby County, MO

The radar

The St Louis radar (KLSX), 164 km from the middle of the area, began a volume at 05:49 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, 5.8 hours before the alert went out and 239 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 2017-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 366 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 2017-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 149 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
366 J/kg
Mixed-layer CIN
-168 J/kg
Mixed-layer LCL
1050 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
149 m²/s²
0-3 km storm-relative helicity
124 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

623 
WGUS53 KLSX 220547
FFWLSX
MOC205-221345-
/O.NEW.KLSX.FF.W.0020.170822T0547Z-170822T1345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
1247 AM CDT TUE AUG 22 2017

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Eastern Shelby County in northeastern Missouri...

* Until 845 AM CDT Tuesday.

* At 1247 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Two to three inches of rain 
  have fallen. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Shelbina, Shelbyville, Emden, Hunnewell and Bethel. 

Additional rainfall amounts of up to 1-2 inches are possible in the 
warned area.

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 flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 3981 9185 3966 9185 3970 9213 3985 9215
      3989 9202

$$

Gosselin
2 follow-up statements
105 
WGUS73 KLSX 220937
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
437 AM CDT TUE AUG 22 2017

MOC205-221345-
/O.CON.KLSX.FF.W.0020.000000T0000Z-170822T1345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Shelby MO-
437 AM CDT TUE AUG 22 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 AM CDT FOR
EASTERN SHELBY COUNTY...

At 436 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Two to four inches of rain have fallen. 

Some locations that will experience flooding include...
Shelbina, Shelbyville, Emden, Hunnewell and Bethel. 

Additional rainfall amounts of up to a half inch are possible in the 
warned area.

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 flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 3981 9185 3966 9185 3970 9213 3985 9215
      3989 9202

$$

Gosselin
072 
WGUS73 KLSX 221350
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
850 AM CDT TUE AUG 22 2017

MOC205-221359-
/O.EXP.KLSX.FF.W.0020.000000T0000Z-170822T1345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Shelby MO-
850 AM CDT TUE AUG 22 2017

...THE FLASH FLOOD WARNING FOR EASTERN SHELBY COUNTY HAS EXPIRED...

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

LAT...LON 3981 9185 3966 9185 3970 9213 3985 9215
      3989 9202

$$

GKS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 7:19 PM CDTSevere Thunderstorm WarningLSXBoone, Cole, Moniteau41 min
Aug 22, 12:36 AM CDTAreal Flood AdvisoryLSXMarion6 hr
Aug 22, 8:57 AM CDTRiver Flood WarningLSXCole62 hr

Nearby

Flash Flood Warnings in Missouri, 2017Every flash flood warning in 2017

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.