Alert archive / Missouri / Flood Watches in 2023

Flood Watch 4, NWS St. Louis, MO

May 15, 202311 counties in Missouri; 9 counties in Illinois

NWS St. Louis, MO issued this flood watch at May 15, 2023, 2:07 PM CDT for 11 counties in Missouri; 9 counties in Illinois. It was in force for 16 hr.

The area

The counties it named.

The facts

Issued: May 15, 2023, 2:07 PM CDT (19:07 UTC)
Expired: May 16, 2023, 6:27 AM CDT
In force: 16 hr
Issued by: NWS St. Louis, MO
Flood severity: None

Counties Bond County, IL, Clinton County, IL, Fayette County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, City of Saint Louis, MO, Crawford County, MO, Franklin County, MO, Iron County, MO, Jefferson County, MO, Madison County, MO, Reynolds County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 67 km from the middle of the area, began a volume at 19:07 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, 7.1 hours before the alert went out and 354 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: 833 J/kg
Mixed-layer CIN: -29 J/kg
Mixed-layer LCL: 813 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 83 m²/s²
0-3 km storm-relative helicity: 76 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flood watch 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 flood watch went out at May 15, 1:23 PM CDT, 44 minutes earlier.

Area forecast discussion, May 15, 1:23 PM CDT, 44 minutes before

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Hazardous weather outlook, May 15, 3:36 AM CDT, 10 hours 31 minutes before

Hazardous Weather Outlook
National Weather Service St Louis MO
336 AM CDT Mon May 15 2023

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-160845-
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-Saint 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-Saint Charles MO-Franklin MO-
Saint Louis MO-Saint Louis City MO-Jefferson MO-Crawford MO-
Washington MO-Saint Francois MO-Sainte Genevieve MO-Iron MO-
Madison MO-Reynolds MO-
336 AM CDT Mon May 15 2023

This Hazardous Weather Outlook is for portions of eastern and
central Missouri as well as west central and southwest Illinois.

.DAY ONE...Today and tonight.

Thunderstorms are likely late this afternoon and early evening across
parts of southeast Missouri. A few of these storms may be strong to
severe with large hail and damaging winds possible. There is also the
potential for locally heavy rainfall in these same locations.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Another chance of thunderstorms exists across the area Thursday night
through Friday night.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report any hail or damaging winds to the
National Weather Service.

Gosselin

In the hours before

Local storm report, May 15, 12:35 PM CDT, 1 hour 32 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
1235 PM CDT MON MAY 15 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0516 PM     TSTM WND DMG     3 NNW FREEBURG          38.47N 89.92W
05/14/2023                   ST. CLAIR          IL   PUBLIC

            DELAYED REPORT. PHOTOS ON TWITTER SHOW A
            TREE SPLIT NEAR ITS BASE LEANING ON A HOUSE.
            TIME ESTIMATED FROM RADAR.

&&

AE

The office that day

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

Issued	Product	Office	Counties	Lasted
May 15, 4:18 AM CDT	River Flood Warning	LSX	Reynolds	52 hr
May 15, 3:09 PM CDT	Severe Thunderstorm Warning	LSX	Reynolds	24 min
May 15, 3:22 PM CDT	Severe Thunderstorm Warning	LSX	Iron, Reynolds	19 min
May 15, 3:51 PM CDT	Areal Flood Advisory	LSX	Reynolds	3 hr
May 15, 4:51 PM CDT	Areal Flood Advisory	LSX	Reynolds	100 min
May 14, 7:28 PM CDT	Severe Thunderstorm Warning	LSX	Marion	47 min
May 14, 7:32 PM CDT	Severe Thunderstorm Warning	LSX	Montgomery	28 min
May 14, 7:44 PM CDT	Areal Flood Advisory	LSX	Fayette, Montgomery	32 min
May 14, 7:48 PM CDT	Areal Flood Advisory	LSX	Marion	35 min
May 14, 7:53 PM CDT	Areal Flood Advisory	LSX	Macoupin	3 hr
May 14, 8:16 PM CDT	Flash Flood Warning	LSX	Fayette, Montgomery	2 hr
May 14, 8:23 PM CDT	Flash Flood Warning	LSX	Marion	2 hr
May 14, 9:09 PM CDT	Areal Flood Advisory	LSX	Bond, Fayette	3 hr
May 14, 10:25 PM CDT	Areal Flood Warning	LSX	Montgomery	6 hr
May 14, 10:29 PM CDT	Areal Flood Warning	LSX	Marion	6 hr
May 14, 10:42 PM CDT	Areal Flood Warning	LSX	Macoupin	6 hr
May 15, 3:26 PM CDT	River Flood Warning	LSX	Fayette	15 hr

Nearby

Flood Watches in Missouri, 2023 Flood Watches in Illinois, 2023 Every flood watch in 2023

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.