Alert archive / Iowa / Severe Thunderstorm Warnings in 2025

Severe Thunderstorm Warning 27, NWS Quad Cities, IA

April 18, 20254 counties in Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Apr 18, 2025, 1:11 AM CDT for 4 counties in Iowa. It was in force for 21 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
Apr 18, 2025, 1:11 AM CDT (06:11 UTC)
Expired
Apr 18, 2025, 1:32 AM CDT
In force
21 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Johnson County, IA, Louisa County, IA, Muscatine County, IA, Washington County, IA

The radar

The Quad Cities radar (KDVN), 73 km from the middle of the area, began a volume at 06:10 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

Davenport, (KDVN), launched 00:00Z, 6.2 hours before the alert went out and 79 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, Davenport, at 00:00Z on 2025-04-18Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 2025-04-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 584 square meters per square second.1939587897Sfc1 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
1462 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
584 m²/s²
0-3 km storm-relative helicity
935 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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 Apr 17, 6:55 PM CDT, 6 hours 16 minutes earlier.

Area forecast discussion, Apr 17, 6:55 PM CDT, 6 hours 16 minutes before
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Hazardous weather outlook, Apr 17, 4:59 AM CDT, 20 hours 12 minutes before
Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
459 AM CDT Thu Apr 17 2025

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-181100-
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-
459 AM CDT Thu Apr 17 2025

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 will be a chance for isolated to scattered thunderstorms
this morning with small hail and lightning the main threats. Later
tonight scattered strong to severe storms will be possible
especially across eastern Iowa. Large hail will be the primary
threat, with damaging wind bursts a secondary concern. There is a
Slight Risk(Level 2 out of 5) for generally the west half of the
Outlook Area tonight, with a Marginal Risk(Level 1 out of 5)
across the rest of the area.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

There is a Slight Risk for severe storms Friday afternoon and
evening generally across Illinois as a cold front sweeps through
the region. A Marginal Risk extends further to the west across far
eastern Iowa and northeast Missouri. All modes of severe weather
will be possible if these storms manage to form in the local area.

There may be another chance for thunderstorms on Sunday. Any risk
of severe weather and heavy rain will be better determined in the
coming days.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed later tonight especially across
Iowa. There is also a chance that spotter activation will be
needed Friday afternoon and evening especially across Illinois.

GENERAL STORM MOTION OF THE DAY: Northeast at 40 to 50 MPH

12

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 17, 11:44 PM CDTSpecial Weather StatementDVNIowa46 min
Apr 18, 1:01 AM CDTSpecial Weather StatementDVNWashington29 min
Apr 18, 7:40 AM CDTSpecial Weather StatementDVNJo Daviess, Stephenson50 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2025Every severe thunderstorm warning in 2025

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.