Alert archive / Illinois / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 124, NWS Quad Cities, IA

April 17, 2026Bureau County, Putnam County, Illinois

NWS Quad Cities, IA issued this severe thunderstorm warning at Apr 17, 2026, 8:46 PM CDT for Bureau County, Putnam County, Illinois. It was in force for 23 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 17, 2026, 8:46 PM CDT (01:46 UTC)
Expired
Apr 17, 2026, 9:09 PM CDT
In force
23 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

Counties Bureau County, IL, Putnam County, IL

The radar

The Quad Cities radar (KDVN), 104 km from the middle of the area, began a volume at 01:46 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.

IssuedProductOfficeLasted
Apr 17, 12:40 PM CDTTornado WatchSPC9 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 1.8 hours before the alert went out and 98 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 2026-04-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 30 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 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 2026-04-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 202 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
30 J/kg
Mixed-layer CIN
-223 J/kg
Mixed-layer LCL
1085 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
202 m²/s²
0-3 km storm-relative helicity
202 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, 6:20 PM CDT, 2 hours 26 minutes earlier. Its key messages:

  • A strong storm system will bring the threat for severe storms once again to our area through this evening. SPC continues to highlight nearly our entire area in an Enhanced Risk (level 3 of 5) for severe weather.
  • A flood watch has been issued for much of the area through tonight for the potential of excessive rainfall with the final round of storms this afternoon/tonight. Soils across the area are saturated north of I-80 and very moist south of I-80.
  • Much cooler conditions are expected this weekend. Unseasonably cool temperatures in the 30s Saturday night and Sunday night will bring the potential for frost/freeze, especially in our north.
  • Area rivers are on the rise from the recent rounds of heavy rain, and heavy rainfall later today may push them even higher. Refer to the hydro section below for more details.
Area forecast discussion, Apr 17, 6:20 PM CDT, 2 hours 26 minutes before
Area Forecast Discussion
National Weather Service Quad Cities IA IL
620 PM CDT Fri Apr 17 2026

.KEY MESSAGES...

- A strong storm system will bring the threat for severe storms
  once again to our area through this evening. SPC continues to
  highlight nearly our entire area in an Enhanced Risk (level 3
  of 5) for severe weather.

- A flood watch has been issued for much of the area through
  tonight for the potential of excessive rainfall with the final
  round of storms this afternoon/tonight. Soils across the area
  are saturated north of I-80 and very moist south of I-80.

- Much cooler conditions are expected this weekend. Unseasonably cool
  temperatures in the 30s Saturday night and Sunday night will
  bring the potential for frost/freeze, especially in our north.

- Area rivers are on the rise from the recent rounds of heavy
  rain, and heavy rainfall later today may push them even
  higher. Refer to the hydro section below for more details.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 1252 PM CDT Fri Apr 17 2026

Convective initiation has occurred across eastern Iowa. The
individual discrete cells will rapidly grow upscale into one or
more broken lines ahead of the cold front.

The atmosphere is becoming increasingly moist so the storms will
have plenty of fuel to produce heavy rainfall. The axis for the
heavier rain is somewhat narrow but rainfall amounts of an inch
in an hour will be possible with the stronger storms. Where
storms linger or repeat over the same areas, rainfall amounts
of 2 to 3 inches in a short time will be possible.

The pre-frontal line(s) of storms look to push east of the
Mississippi in the 6-8 PM time frame with the cold front
arriving during the mid to late evening hours. Very short range
models which had been pointing to a solid line of storms with
the front are now trending toward a scattered to broken line
with not much thunder associated with it. This 'may' be an
indication the convective allowing models are struggling with
the overall forcing from the upper level system.

The bulk of the rain looks to end across the area by midnight
but scattered rain showers along and immediately behind the
front will linger past midnight. However, the overall trend will
be decreasing areal coverage from west to east after midnight.

&&

.LONG TERM /SATURDAY THROUGH FRIDAY/...
Issued at 306 AM CDT Fri Apr 17 2026

Much colder air will continue to move into the area for the weekend
as a northwest flow pattern develops aloft. An area of high pressure
will build into the area Saturday night, which could set up our
first bout of frost/freeze conditions during the growing season.
There does appear to be a mid-level trough sweeping through the area
Saturday night, which could result in some cloud cover that could
keep our temperatures from falling too much, limiting our
frost/freeze potential. Despite this, the NBM probabilities of
freezing temperatures Saturday night are still around 50-80% along
and north of Interstate 80. Another night of frost/freeze conditions
are possible Sunday night as well, with similar exceedance
probabilities for freezing temperatures.

A quieter weather pattern will persist into early next week as a
broad upper ridge remains in place through the central US. A larger
trough begins to take shape across the western US into the latter
portion of the week. Therefore, some warming and a move toward some
smaller precipitation chances (20-40%) start to return to the area
by Thursday with a larger storm system potentially nearing the
region for Friday.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 619 PM CDT Fri Apr 17 2026

A line of storms continue to progress across the area along a
cold front. Most of the TSRA is forecast to be at or moving away
from the Terminals within the first 2 hours of the forecast
period, mainly impacting MLI and BRL as the line as has already
cleared DBQ and CID as of writing. Some low IFR CIGS and
possible lingering showers this evening through about 10pm to
midnight at the latest are plausible behind the cold front with
only occasional lightning associated. Gusty northwesterly winds
overnight into Saturday, with skies clearing.

&&

.HYDROLOGY...
Issued at 1136 AM CDT Thu Apr 16 2026

Discussion...

Over the past five days, multiple rounds of heavy rain have
impacted eastern Iowa, northern Illinois and southern Wisconsin.
Rainfall amounts have run from 2 to 5 inches of rain; much of
this rain has been north of Highway 30.

Another round of heavy rain is forecast this afternoon and
evening with amounts running from a half inch to around 1.5
inches. With area soils running from moist to near saturation,
this additional rainfall will quickly run off into area
waterways resulting in new or increased river flooding along
with the potential for flash flooding.

Much of this rain is forecast to fall across southeast Iowa,
west central Illinois and into northern Illinois. River basins
impacted would be the Rock, lower Iowa, Skunk, Des Moines and La
Moine.

Rock River...

Based on overall river forecasts and another round of heavy rain
expected today, confidence is high (>80%) that the entire
length of the Rock River will reach flood stage by the weekend
and remain above flood stage into much of next week.

Mississippi River...

Routed flow coming down from the upper Mississippi, Wisconsin,
Rock, Iowa and other tributary rivers will cause general rises
along the length of the Mississippi. Based on the current routed
flow and another round of heavy rain, confidence is high (>80%)
that the Mississippi will reach flood stage from Muscatine down
through Keithsburg and at Gregory Landing. Gladstone and
Burlington are already above flood stage and will see additional
rises as the additional routed flow arrives over the weekend
and into next week.

Iowa Tributary Rivers...

Rivers in eastern Iowa are running high from the rounds of heavy
rain. Flood warnings continue for the lower Wapsipinicon River
near DeWitt and the Iowa River above Coralville near Marengo.
Based on routed flow, the lower Cedar River near Conesville will
go above flood stage over the weekend.

The North Skunk River near Sigourney is forecast to go above
flood stage tonight with general rises expected farther
downstream and on the Skunk River.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Flood Watch until 4 AM CDT Saturday for IAZ040>042-052>054-
     064>068-077-078-088-089-099.
IL...Flood Watch until 4 AM CDT Saturday for ILZ001-002-007-009-
     015>018-024>026-034-035.
MO...Flood Watch until 4 AM CDT Saturday for MOZ010.

&&

SHORT TERM...08
LONG TERM...Schultz
AVIATION...NWS
HYDROLOGY...08
Hazardous weather outlook, Apr 17, 3:23 AM CDT, 17 hours 23 minutes before
Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
323 AM CDT Fri Apr 17 2026

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-180900-
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-
323 AM CDT Fri Apr 17 2026

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

An Enhanced Risk (Level 3 of 5) for severe weather remains in
place across the area for this afternoon and evening. Damaging
winds and tornadoes, some possibly strong, are the primary
threats. Localized flash flooding is also possible.

Southerly winds will gust to around 40 mph this afternoon prior to
the severe thunderstorm development.

Area rivers are experiencing flooding. Please see the latest Flood
Statements and Flood Warnings for details.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

Much colder air will bring the potential for frost and freeze
conditions to parts of the area Saturday night and Sunday night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is likely for this afternoon and evening.

JTS

In the hours before

Local storm report, Apr 17, 6:59 PM CDT, 1 hour 47 minutes before
Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
659 PM CDT Fri Apr 17 2026

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

0345 PM     Tstm Wnd Dmg     Lena                    42.38N 89.83W
04/17/2026                   Stephenson         IL   Public

            Photos show structural damage to houses.
            Relayed via social media. Tornado possible.

&&

CMD
Local storm report, Apr 17, 7:56 PM CDT, 50 minutes before
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Local storm report, Apr 17, 8:01 PM CDT, 45 minutes before
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Local storm report, Apr 17, 8:15 PM CDT, 31 minutes before
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Local storm report, Apr 17, 8:21 PM CDT, 25 minutes before
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Local storm report, Apr 17, 8:36 PM CDT, 10 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Apr 18, 11:22 AM CDTRiver Flood WatchDVNClinton, Scott58 hr
Apr 17, 7:08 PM CDTTornado Warning Tornado observedDVNHancock, McDonough52 min
Apr 17, 7:42 PM CDTSevere Thunderstorm Warning Considerable damage threatDVNBureau, Putnam63 min
Apr 17, 7:44 PM CDTTornado WarningDVNBureau, Putnam61 min
Apr 18, 5:50 AM CDTRiver Flood WarningDVNHancock, McDonough70 hr

Nearby

Severe Thunderstorm Warnings in Illinois, 2026Every severe thunderstorm warning in 2026

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.