Alert archive / Missouri / Flash Flood Warnings in 2018

Flash Flood Warning 28, NWS St. Louis, MO

August 9, 2018Sainte Genevieve County, Saint Francois County, Missouri

NWS St. Louis, MO issued this flash flood warning at Aug 9, 2018, 11:00 AM CDT for Sainte Genevieve County, Saint Francois County, Missouri. It was in force for 5 hr. 1 report 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
Aug 9, 2018, 11:00 AM CDT (16:00 UTC)
Expired
Aug 9, 2018, 3:46 PM CDT
In force
5 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

Counties Saint Francois County, MO, Sainte Genevieve County, MO

The radar

The St Louis radar (KLSX), 110 km from the middle of the area, began a volume at 16:00 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

TimeReportWhereRemark
Aug 9, 12:35 PM CDTFLASH FLOOD4 Se Coffman, MOFLOODING IS OCCURRING ALONG COLDWATER AND ALEXANDER CREEKS, FLOODING COLDWATER CLUB RD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 4.0 hours before the alert went out and 308 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, Lincoln, IL at 12:00Z on 2018-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Lincoln, IL at 12:00Z on 2018-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 77 square meters per square second.1939Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1244 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
77 m²/s²
0-3 km storm-relative helicity
78 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

101 
WGUS53 KLSX 091600
FFWLSX
MOC186-187-092200-
/O.NEW.KLSX.FF.W.0028.180809T1600Z-180809T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
1100 AM CDT THU AUG 9 2018

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Southern Ste. Genevieve County in southeastern Missouri...
  Southern St. Francois County in southeastern Missouri...

* Until 500 PM CDT Thursday.

* At 1059 AM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to three inches of rain have
  already fallen. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Farmington, Bismarck, Park Hills, Iron Mountain Lake, Iron
  Mountain, Coffman, Womac, Knob Lick, Leadington, Libertyville, Doe
  Run and Minnith.

This also includes St. Joe State Park and Hawn State Park.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3783 9064 3784 8998 3768 9011 3764 9015
      3765 9065

$$

Tilly
2 follow-up statements
562 
WGUS73 KLSX 091739
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
1239 PM CDT THU AUG 9 2018

MOC186-187-092200-
/O.CON.KLSX.FF.W.0028.000000T0000Z-180809T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Ste. Genevieve MO-St. Francois MO-
1239 PM CDT THU AUG 9 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 500 PM CDT FOR
SOUTHERN STE. GENEVIEVE AND SOUTHERN ST. FRANCOIS COUNTIES...

At 1237 PM CDT, the public reported flash flooding occurring in 
southern portions of Ste. Genevieve County. Three to five inches of 
rain have fallen. Flash flooding is already occurring along portions 
of Coldwater and Alexander Creeks.

Some locations that will experience flooding include...
Farmington, Bismarck, Park Hills, Iron Mountain Lake, Iron Mountain,
Coffman, Womac, Knob Lick, Leadington, Libertyville, Doe Run and
Minnith.

This also includes Mark Twain National Forest, St. Joe State Park 
and Hawn State Park.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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. 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 3783 9064 3784 8998 3768 9011 3764 9015
      3765 9065

$$

Tilly
635 
WGUS73 KLSX 092046
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
346 PM CDT THU AUG 9 2018

MOC186-187-092055-
/O.CAN.KLSX.FF.W.0028.000000T0000Z-180809T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Ste. Genevieve MO-St. Francois MO-
346 PM CDT THU AUG 9 2018

...THE FLASH FLOOD WARNING FOR SOUTHERN STE. GENEVIEVE AND SOUTHERN
ST. FRANCOIS COUNTIES IS CANCELLED...

The heavy rainfall has ended and flood waters are receding. Flooding 
is no longer expected to pose a threat. Please continue to heed any 
remaining road closures.

LAT...LON 3783 9064 3784 8998 3768 9011 3764 9015
      3765 9065

$$

Tilly

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 10:02 AM CDTAreal Flood AdvisoryLSXCrawford, Iron, Reynolds, Washington118 min

Nearby

Flash Flood Warnings in Missouri, 2018Every 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.