Alert archive / Missouri / Flash Flood Watches in 2012

Flash Flood Watch 2, NWS St. Louis, MO

April 13, 201216 counties in Missouri; 5 counties in Illinois

NWS St. Louis, MO issued this flash flood watch at Apr 13, 2012, 9:19 PM CDT for 16 counties in Missouri; 5 counties in Illinois. It was in force for 13 hr.

The area

The counties it named.

The facts

Issued
Apr 13, 2012, 9:19 PM CDT (02:19 UTC)
Expired
Apr 14, 2012, 10:00 AM CDT
In force
13 hr
Issued by
NWS St. Louis, MO
Flood severity
None
All 21 counties

Calhoun County, IL, Jersey County, IL, Madison County, IL, Monroe County, IL, Saint Clair County, IL, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Lincoln County, MO, Moniteau County, MO, Montgomery County, MO, Osage County, MO, Saint Charles County, MO, Saint Louis County, MO, Warren County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 34 km from the middle of the area, began a volume at 02:19 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

Lincoln, IL (KILX), launched 00:00Z, 2.3 hours before the alert went out and 271 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 00:00Z on 2012-04-14Temperature 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 00:00Z on 2012-04-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 260 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
739 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
260 m²/s²
0-3 km storm-relative helicity
284 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

261 
WGUS63 KLSX 140219
FFALSX

URGENT - IMMEDIATE BROADCAST REQUESTED
FLOOD WATCH
NATIONAL WEATHER SERVICE ST LOUIS MO
919 PM CDT FRI APR 13 2012

.SEVERAL ROUNDS OF THUNDERSTORMS WILL BE MOVING ACROSS CENTRAL AND
EAST CENTRAL MISSOURI OVERNIGHT AND EARLY SATURDAY MORNING.
BECAUSE THE STORMS WILL CONTINUE TO IMPACT THE SAME AREAS...HEAVY
RAIN AND FLASH FLOODING WILL BECOME A VERY REAL THREAT.

ILZ098>102-MOZ041-047>052-059>065-072-073-141500-
/O.NEW.KLSX.FF.A.0002.120414T0219Z-120414T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-BOONE MO-
MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-LINCOLN MO-
GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-ST. LOUIS MO-
ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-WASHINGTON MO-
INCLUDING THE CITIES OF...EDWARDSVILLE...BELLEVILLE...COLUMBIA...
JEFFERSON CITY...ST CHARLES...UNION...ST LOUIS
919 PM CDT FRI APR 13 2012

...FLASH FLOOD WATCH IN EFFECT THROUGH SATURDAY MORNING...

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* FLASH FLOOD WATCH FOR PORTIONS OF SOUTHWEST ILLINOIS AND 
  MISSOURI...INCLUDING THE FOLLOWING COUNTIES...IN SOUTHWEST 
  ILLINOIS...CALHOUN IL...JERSEY IL...MADISON IL...MONROE IL 
  AND ST. CLAIR IL. IN MISSOURI...BOONE MO...CALLAWAY MO...COLE 
  MO...CRAWFORD MO...FRANKLIN MO...GASCONADE MO...JEFFERSON 
  MO...LINCOLN MO...MONITEAU MO...MONTGOMERY MO...OSAGE MO...
  ST. CHARLES MO...ST. LOUIS CITY MO...ST. LOUIS MO...WARREN MO 
  AND WASHINGTON MO.

* THROUGH SATURDAY MORNING

* SEVEREAL ROUNDS OF THUNDERSTORMS WILL BE MOVING ACROSS CENTRAL
  AND EAST CENTRAL MISSOURI AND SOUTHWEST ILLINOIS OVERNIGHT AND
  EARLY SATURDAY MORNING. THIS WILL RESULT IN HEAVY RAINS OF 1 TO
  3 INCHES...WITH LOCALLY HIGHER AMOUNTS.

* RUNOFF FROM THIS HEAVY RAIN WILL CAUSE RAPID RISES AND POSSIBLY
  FLOODING ON SMALL CREEKS AND STREAMS...AND WILL ALSO CAUSE
  FLOODING IN LOW LYING AND POORLY DRAINED AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT FLASH FLOODING IS POSSIBLE BUT NOT
IMMINENT IN THE WATCH AREA. PEOPLE IN THE WATCH AREA SHOULD BE
AWARE OF THE POSSIBILITY OF HEAVY RAINFALL AND FLASH FLOODING.
CHECK YOUR PREPAREDNESS REQUIREMENTS...ESPECIALLY IF YOU LIVE IN
FLOOD PRONE AREAS. STAY INFORMED...AND BE READY FOR QUICK ACTION
IF FLOODING IS OBSERVED OR IF A FLASH FLOOD WARNING IS ISSUED.

&&

$$

TRUETT
2 follow-up statements
280 
WGUS63 KLSX 140900
FFALSX

FLOOD WATCH
NATIONAL WEATHER SERVICE ST LOUIS MO
400 AM CDT SAT APR 14 2012

ILZ098>102-MOZ041-047>052-059>065-072-073-141500-
/O.CON.KLSX.FF.A.0002.000000T0000Z-120414T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-BOONE MO-
MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-LINCOLN MO-
GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-ST. LOUIS MO-
ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-WASHINGTON MO-
INCLUDING THE CITIES OF...EDWARDSVILLE...BELLEVILLE...COLUMBIA...
JEFFERSON CITY...ST CHARLES...UNION...ST LOUIS
400 AM CDT SAT APR 14 2012

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 10 AM CDT THIS
MORNING...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF SOUTHWEST ILLINOIS AND MISSOURI...INCLUDING THE 
  FOLLOWING COUNTIES...IN SOUTHWEST ILLINOIS...CALHOUN IL...
  JERSEY IL...MADISON IL...MONROE IL AND ST. CLAIR IL. IN 
  MISSOURI...BOONE MO...CALLAWAY MO...COLE MO...CRAWFORD MO...
  FRANKLIN MO...GASCONADE MO...JEFFERSON MO...LINCOLN MO...
  MONITEAU MO...MONTGOMERY MO...OSAGE MO...ST. CHARLES MO...ST. 
  LOUIS CITY MO...ST. LOUIS MO...WARREN MO AND WASHINGTON MO.

* UNTIL 10 AM CDT THIS MORNING

* DOPPLER RADAR ESTIMATES THAT 1 TO 2 INCHES OF RAIN HAS ALREADY
  FALLEN OVER THE PAST 24 HOURS...WITH LOCALIZED AMOUNTS IN EXCESS
  OF 3 INCHES ACROSS PARTS OF CENTRAL MISSOURI. ADDITIONAL HEAVY
  RAIN IS LIKELY THIS MORNING ACROSS THE WATCH AREA.

* RUNOFF FROM THIS HEAVY RAIN WILL CAUSE RAPID RISES AND 
  POSSIBLY FLOODING ON SMALL CREEKS AND STREAMS...AND WILL ALSO 
  CAUSE FLOODING IN LOW LYING AND POORLY DRAINED AREAS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT FLASH FLOODING IS POSSIBLE BUT NOT
IMMINENT IN THE WATCH AREA. PEOPLE IN THE WATCH AREA SHOULD BE
AWARE OF THE POSSIBILITY OF HEAVY RAINFALL AND FLASH FLOODING.
CHECK YOUR PREPAREDNESS REQUIREMENTS...ESPECIALLY IF YOU LIVE IN
FLOOD PRONE AREAS. STAY INFORMED...AND BE READY FOR QUICK ACTION
IF FLOODING IS OBSERVED OR IF A FLASH FLOOD WARNING IS ISSUED.

&&

$$

CARNEY
048 
WGUS63 KLSX 141518
FFALSX

FLOOD WATCH
NATIONAL WEATHER SERVICE ST LOUIS MO
1018 AM CDT SAT APR 14 2012

ILZ098>102-MOZ041-047>052-059>065-072-073-141630-
/O.EXP.KLSX.FF.A.0002.000000T0000Z-120414T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-BOONE MO-
MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-LINCOLN MO-
GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-ST. LOUIS MO-
ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-WASHINGTON MO-
INCLUDING THE CITIES OF...EDWARDSVILLE...BELLEVILLE...COLUMBIA...
JEFFERSON CITY...ST CHARLES...UNION...ST LOUIS
1018 AM CDT SAT APR 14 2012

...FLASH FLOOD WATCH HAS EXPIRED...

THE FLASH FLOOD WATCH FOR PORTIONS OF SOUTHWEST ILLINOIS AND
CENTRAL AND SOUTHEAST MISSOURI HAS EXPIRED. ALTHOUGH SHOWERS AND
THUNDERSTORMS WILL CONTINUE IN THIS AREA FOR THE REST OF THE
MORNING...THE RAINFALL RATES OR INTENSITY OF THE RAINFALL WILL WEAKEN.
RESIDENTS OF THIS AREA WILL STILL NEED TO DRIVE WITH EXTRA
CAUTION AS PREVIOUS HEAVY RAINFALL HAS CAUSED SOME CREEKS TO FLOOD
WITH WATER OVER ROADWAYS IN PLACES THAT HAS YET TO RECEDE.


$$

GKS

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 14, 1:26 AM CDTRiver Flood WarningLSXCole3 days
Apr 14, 1:53 AM CDTAreal Flood AdvisoryLSXSaint Louis, City of Saint Louis4 hr
Apr 14, 6:27 AM CDTAreal Flood AdvisoryLSXCole, Osage4 hr
Apr 14, 7:06 AM CDTRiver Flood WarningLSXOsage24 hr
Apr 14, 7:13 AM CDTFlash Flood WarningLSXCole, Osage6 hr
Apr 14, 7:38 AM CDTAreal Flood AdvisoryLSXGasconade4 hr
Apr 14, 11:14 AM CDTRiver Flood WarningLSXSaint Charles20 hr
Apr 14, 3:30 PM CDTRiver Flood WarningLSXLincoln16 hr

Nearby

Flash Flood Watches in Missouri, 2012Flash Flood Watches in Illinois, 2012Every flash flood watch in 2012

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.