Alert archive / Missouri / Areal Flood Advisories in 2011

Areal Flood Advisory 13, NWS St. Louis, MO

May 20, 2011Cole County, Missouri

NWS St. Louis, MO issued this areal flood advisory at May 20, 2011, 5:35 PM CDT for Cole County, Missouri. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
May 20, 2011, 5:35 PM CDT (22:35 UTC)
Expired
May 20, 2011, 10:00 PM CDT
In force
4 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon

County Cole County, MO

The radar

The St Louis radar (KLSX), 141 km from the middle of the area, began a volume at 22:35 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

Springfield, MO (KSGF), launched 12:00Z, 10.6 hours before the alert went out and 223 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, Springfield, MO at 12:00Z on 2011-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 537 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Springfield, MO at 12:00Z on 2011-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 222 square meters per square second.193958Sfc1 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
537 J/kg
Mixed-layer CIN
-280 J/kg
Mixed-layer LCL
940 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
222 m²/s²
0-3 km storm-relative helicity
161 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS St. Louis, MO wrote its last area forecast discussion before this areal flood advisory went out at May 20, 3:55 PM CDT, 1 hour 40 minutes earlier.

Area forecast discussion, May 20, 3:55 PM CDT, 1 hour 40 minutes before
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Hazardous weather outlook, May 20, 4:01 PM CDT, 1 hour 34 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
401 PM CDT FRI MAY 20 2011

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-211130-
GREENE IL-MACOUPIN IL-MONTGOMERY IL-BOND IL-FAYETTE IL-CLINTON IL-
MARION IL-WASHINGTON IL-RANDOLPH IL-ADAMS IL-BROWN IL-PIKE IL-
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-KNOX MO-
LEWIS MO-SHELBY MO-MARION MO-MONROE MO-RALLS MO-PIKE MO-BOONE MO-
AUDRAIN 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-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO-
MADISON MO-REYNOLDS MO-
401 PM CDT FRI MAY 20 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN AND
CENTRAL MISSOURI AS WELL AS WEST CENTRAL AND SOUTHWEST ILLINOIS.

.DAY ONE...TONIGHT

THUNDERSTORMS ARE EXPECTED ACROSS THE AREA TONIGHT. SOME OF THE
STORMS COULD PRODUCE LOCALLY HEAVY RAINFALL. A FEW STORMS ACROSS
SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS COULD BE SEVERE AND
CAPABLE OF PRODUCING HAIL AND DAMAGING WIND GUSTS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THUNDERSTORMS ARE LIKELY ON SATURDAY. SOME OF THE STORMS COULD BE
STRONG TO SEVERE AND CAPABLE OF PRODUCING LARGE HAIL AND DAMAGING
WIND GUSTS.

THERE IS A CHANCE FOR THUNDERSTORMS FOR MUCH OF THE PERIOD FROM
SATURDAY NIGHT THROUGH WEDNESDAY NIGHT. SOME OF THE STORMS ON
SUNDAY AFTERNOON AND EVENING MAY BE STRONG TO SEVERE.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ASKED TO REPORT SEVERE WEATHER TO THE NATIONAL
WEATHER SERVICE IN ST. LOUIS.

KANOFSKY

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 4:09 AM CDTRiver Flood WarningLSXOsage33 hr
May 20, 10:55 AM CDTRiver Flood WarningLSXCallaway, Osage104 days
May 20, 10:55 AM CDTRiver Flood WarningLSXGasconade, Montgomery106 days
May 20, 10:55 AM CDTRiver Flood WarningLSXGasconade, Montgomery102 days
May 20, 1:18 PM CDTFlash Flood WarningLSXMoniteau4 hr
May 20, 4:56 PM CDTFlash Flood WarningLSXMoniteau5 hr

Nearby

Areal Flood Advisories in Missouri, 2011Every areal flood advisory in 2011

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.