Alert archive / Missouri / Flash Flood Warnings in 2018

Flash Flood Warning 43, NWS St. Louis, MO

September 8, 2018Crawford County, Missouri

NWS St. Louis, MO issued this flash flood warning at Sep 8, 2018, 2:56 AM CDT for Crawford County, Missouri. It was in force for 6 hr. 2 reports 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: Sep 8, 2018, 2:56 AM CDT (07:56 UTC)
Expired: Sep 8, 2018, 9:00 AM CDT
In force: 6 hr
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Flood severity: None

County Crawford County, MO

The radar

The St Louis radar (KLSX), 109 km from the middle of the area, began a volume at 07:59 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
Sep 8, 6:00 AM CDT	HEAVY RAIN 4.36	7 S Steelville, MO	STORM TOTAL SO FAR. 2.70 INCHES HAS FALLEN SINCE MIDNIGHT.
Sep 8, 8:45 AM CDT	FLOOD	Steelville, MO	SEVERAL ROADS FLOODED AND CLOSED AROUND STEELVILLE.

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 00:00Z, 7.9 hours before the alert went out and 247 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: 729 J/kg
Mixed-layer CIN: 0 J/kg
Mixed-layer LCL: 470 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 31 m²/s²
0-3 km storm-relative helicity: 62 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

841 
WGUS53 KLSX 080756
FFWLSX
MOC055-081400-
/O.NEW.KLSX.FF.W.0043.180908T0756Z-180908T1400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
256 AM CDT SAT SEP 8 2018

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Crawford County in east central Missouri...

* Until 900 AM CDT Saturday.

* At 255 AM CDT, Doppler radar indicated heavy rain across the 
  warned area. Between three and five inches of rain have already 
  fallen. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Cuba, Steelville, Bourbon, Leasburg, Cherryville, Dillard, Cook
  Station and Davisville.

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

This includes Interstate 44 in Missouri between exits 203 and 214.
 
This also includes  Onondaga Cave State Park and Dillard Mill
Historic Site.
 
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.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

&&

LAT...LON 3770 9131 3779 9131 3779 9153 3814 9152
      3816 9110 3786 9109 3774 9110 3774 9115
      3770 9115

$$

Byrd

1 follow-up statement

141 
WGUS73 KLSX 081142
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
642 AM CDT SAT SEP 8 2018

MOC055-081400-
/O.CON.KLSX.FF.W.0043.000000T0000Z-180908T1400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Crawford MO-
642 AM CDT SAT SEP 8 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 900 AM CDT FOR
CRAWFORD COUNTY...

At 638 AM CDT, Doppler radar indicated the heavy rain has tapered 
off across the warned area. Between 2 and 6 inches has fallen across 
the county. The heaviest amounts were in an area between Leasburg 
and Steelville. Even though the rain has tapered off flash flooding 
is still expected to begin shortly.

Some locations that will experience flooding include...
Cuba, Steelville, Bourbon, Leasburg, Cherryville, Dillard, Cook
Station and Davisville.

This includes Interstate 44 in Missouri between exits 203 and 214.
 
This also includes  Onondaga Cave State Park and Dillard Mill
Historic Site.
 
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.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

&&

LAT...LON 3770 9131 3779 9131 3779 9153 3814 9152
      3816 9110 3786 9109 3774 9110 3774 9115
      3770 9115

$$

Byrd

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 7, 7:28 PM CDT	River Flood Warning	LSX	Marion	17 hr
Sep 7, 8:02 PM CDT	Flash Flood Warning	LSX	Franklin, Jefferson, Washington	6 hr
Sep 7, 8:34 PM CDT	Flash Flood Warning	LSX	Jefferson, Sainte Genevieve	5 hr
Sep 7, 9:27 PM CDT	Areal Flood Advisory	LSX	Saint Charles, Saint Louis, City of Saint Louis	4 hr
Sep 8, 1:31 AM CDT	Areal Flood Warning	LSX	Franklin, Jefferson, Sainte Genevieve, Washington	12 hr
Sep 8, 8:44 AM CDT	Areal Flood Warning	LSX	Jefferson, Saint Louis, City of Saint Louis	6 hr
Sep 8, 8:59 AM CDT	Areal Flood Warning	LSX	Crawford	6 hr
Sep 8, 1:28 PM CDT	Areal Flood Warning	LSX	Jefferson, Sainte Genevieve	6 hr

Nearby

Flash Flood Warnings in Missouri, 2018 Every flash flood warning in 2018

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.