Alert archive / Iowa / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 124, NWS Quad Cities, IA

May 21, 2024Benton County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at May 21, 2024, 6:21 AM CDT for Benton County, Iowa. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 21, 2024, 6:21 AM CDT (11:21 UTC)
Expired: May 21, 2024, 7:00 AM CDT
In force: 39 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Benton County, IA

The radar

The Quad Cities radar (KDVN), 134 km from the middle of the area, began a volume at 11:21 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 21, 6:15 AM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 11.4 hours before the alert went out and 139 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: 812 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 1664 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 15 m²/s²
0-3 km storm-relative helicity: 47 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Quad Cities, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at May 21, 5:38 AM CDT, 43 minutes earlier.

Area forecast discussion, May 21, 5:38 AM CDT, 43 minutes before

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Hazardous weather outlook, May 21, 4:15 AM CDT, 2 hours 6 minutes before

Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
415 AM CDT Tue May 21 2024

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-220915-
Buchanan-Delaware-Dubuque-Benton-Linn-Jones-Jackson-Iowa-Johnson-
Cedar-Clinton-Muscatine-Scott-Keokuk-Washington-Louisa-Jefferson-
Henry IA-Des Moines-Van Buren-Lee-Jo Daviess-Stephenson-Carroll-
Whiteside-Rock Island-Henry IL-Bureau-Putnam-Mercer-Henderson-
Warren-Hancock-McDonough-Scotland-Clark-
415 AM CDT Tue May 21 2024

This Hazardous Weather Outlook is for portions of north central
Illinois...northwest Illinois...west central Illinois...east
central Iowa...northeast Iowa...southeast Iowa and northeast
Missouri.

.DAY ONE...TODAY AND TONIGHT

There is a Moderate Risk, or a level 4 out of 5 for severe
weather today for the entire outlook area. All severe hazards will
be possible including damaging winds of 60 to 80 mph, tornadoes,
and large hail. In addition, repeated rounds of thunderstorms may
bring an isolated flash flood risk and ponding of water.

Portions of the Cedar, Skunk, and Wapsipinicon rivers are
experiencing flooding. Please see the latest Flood Statements and
Flood Warnings for details.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will be needed today and tonight.

GENERAL STORM MOTION OF THE DAY:

To the northeast at 55 mph.

Gross

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 20, 7:43 PM CDT	River Flood Watch	DVN	Benton, Iowa	14 hr
May 20, 7:47 PM CDT	River Flood Watch	DVN	Keokuk	3 hr
May 20, 7:47 PM CDT	River Flood Watch	DVN	Clinton, Scott	3 days
May 20, 10:17 PM CDT	River Flood Warning	DVN	Keokuk	7 days
May 21, 1:45 AM CDT	Flood Watch	DVN	Benton, Buchanan, Delaware, Iowa, Johnson, Linn	19 hr
May 21, 6:51 AM CDT	Severe Thunderstorm Warning	DVN	Benton, Iowa, Linn	28 min
May 21, 8:46 AM CDT	Special Weather Statement	DVN	Jones	44 min
May 21, 9:40 AM CDT	River Flood Warning	DVN	Benton, Iowa	14 days
May 21, 10:54 AM CDT	Special Weather Statement	DVN	Benton, Buchanan, Delaware, Dubuque, Linn	51 min
May 21, 10:56 AM CDT	River Flood Watch	DVN	Cedar, Jones, Linn	6 days
May 21, 11:51 AM CDT	Severe Thunderstorm Warning	DVN	Iowa	54 min
May 21, 12:34 PM CDT	Flash Flood Warning	DVN	Iowa	4 hr
May 21, 12:43 PM CDT	Severe Thunderstorm Warning	DVN	Benton, Iowa, Johnson, Linn	29 min
May 21, 1:16 PM CDT	Special Weather Statement	DVN	Johnson, Jones, Linn	59 min
May 21, 2:52 PM CDT	Severe Thunderstorm Warning	DVN	Delaware, Dubuque, Jones	43 min
May 21, 3:28 PM CDT	Severe Thunderstorm Warning	DVN	Dubuque	33 min
May 21, 5:21 PM CDT	Severe Thunderstorm Warning	DVN	Van Buren	39 min
May 21, 5:43 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DVN	Benton, Buchanan	47 min
May 21, 5:54 PM CDT	Severe Thunderstorm Warning	DVN	Delaware, Dubuque, Jones	51 min
May 21, 5:54 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DVN	Henry, Jefferson, Van Buren, Washington	33 min
May 21, 6:02 PM CDT	Severe Thunderstorm Warning	DVN	Cedar, Clinton, Jackson, Jones	43 min
May 21, 6:05 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DVN	Des Moines, Henry, Lee, Louisa, Van Buren	25 min
May 21, 6:18 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DVN	Benton, Iowa, Johnson, Keokuk	42 min
May 21, 6:24 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DVN	Benton, Buchanan, Delaware, Linn	51 min
May 21, 6:29 PM CDT	Severe Thunderstorm Warning	DVN	Dubuque	31 min
May 21, 6:32 PM CDT	Tornado Warning	DVN	Benton, Buchanan	28 min
May 21, 6:38 PM CDT	Severe Thunderstorm Warning	DVN	Cedar, Clinton, Johnson, Louisa, Muscatine, Scott	52 min
May 21, 6:43 PM CDT	Severe Thunderstorm Warning	DVN	Van Buren	47 min
May 21, 6:47 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DVN	Jackson	43 min
May 21, 6:52 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DVN	Benton, Buchanan, Delaware, Johnson, Jones, Linn	38 min
May 21, 6:55 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DVN	Cedar, Clinton, Jackson, Jones	50 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2024 Every severe thunderstorm warning in 2024

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.