Alert archive / Iowa / Flash Flood Warnings in 2026

Flash Flood Warning 22, NWS Quad Cities, IA

June 17, 2026Johnson County, Linn County, Iowa

NWS Quad Cities, IA issued this flash flood warning at Jun 17, 2026, 7:24 AM CDT for Johnson County, Linn County, Iowa. It was in force for 6 hr. 7 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 17, 2026, 7:24 AM CDT (12:24 UTC)
Expired
Jun 17, 2026, 1:18 PM CDT
In force
6 hr
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Flood severity
None

Counties Johnson County, IA, Linn County, IA

The radar

The Quad Cities radar (KDVN), 93 km from the middle of the area, began a volume at 12:27 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.

What was reported inside it

TimeReportWhereRemark
Jun 17, 7:29 AM CDTFLASH FLOOD3 Wsw Cedar Rapids, IA2 to 3 feet deep water with a car stuck at location.
Jun 17, 7:41 AM CDTFLASH FLOOD2 Ne Cedar Rapids, IA6 to 10 inches of water running across the roads in the area including 19th St SE and 2nd Ave SE. Cars driving through are stalling out. Delayed report.
Jun 17, 9:17 AM CDTRAIN 1.312 Nw North Liberty, IA
Jun 17, 9:45 AM CDTFLASH FLOOD3 W Cedar Rapids, IAWiley Blvd NW is closed north of Johnson Ave NW due to flooding. Also, flooding reported at 33rd Ave SW and 6th St. SW.
Jun 17, 11:35 AM CDTRAIN 2.352 W Cedar Rapids, IA
Jun 17, 11:38 AM CDTRAIN 2.111 Ne Fairfax, IARainfall so far today.
Jun 17, 12:54 PM CDTFLASH FLOOD3 Sse Ely, IARoads closed due to high water - 140th St between Ely Rd and Naples, Sandy Beach Rd at the Beach, and Chambers Ave at posted low water crossing. Time estimated.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 4 storm reports to this flash flood warning; the first came 5 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 0.4 hours before the alert went out and 99 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 12:00Z on 2026-06-17Temperature 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 12:00Z on 2026-06-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 179 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2165 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
179 m²/s²
0-3 km storm-relative helicity
218 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

654 
WGUS53 KDVN 171224
FFWDVN
IAC103-113-171830-
/O.NEW.KDVN.FF.W.0022.260617T1224Z-260617T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Quad Cities IA IL
724 AM CDT Wed Jun 17 2026

The National Weather Service in Quad Cities has issued a

* Flash Flood Warning for...
  Johnson County in east central Iowa...
  Southern Linn County in east central Iowa...

* Until 130 PM CDT Wednesday.

* At 724 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Additional rainfall amounts of 0.5 to 1.5 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Cedar Rapids, Iowa City, West Branch, Marion, Coralville, North 
  Liberty, Hiawatha, Mount Vernon, Lisbon, Fairfax, Solon, Tiffin, 
  Ely, Walford, Springville, University Heights, Swisher, Oxford, 
  Shueyville and Bertram.

This includes the following highways...
	Interstate 80 in Iowa between mile markers 230 and 253.
	Interstate 380 between mile markers 1 and 25.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4204 9183 4204 9166 4204 9137 4176 9137
      4162 9137 4163 9183 4201 9183

FLASH FLOOD...RADAR INDICATED

$$

Schreck
2 follow-up statements
702 
WGUS73 KDVN 171447
FFSDVN

Flash Flood Statement
National Weather Service Quad Cities IA IL
947 AM CDT Wed Jun 17 2026

IAC103-113-171830-
/O.CON.KDVN.FF.W.0022.000000T0000Z-260617T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Johnson IA-Linn IA-
947 AM CDT Wed Jun 17 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 130 PM CDT THIS 
AFTERNOON FOR JOHNSON AND SOUTHERN LINN COUNTIES...

At 947 AM CDT, Emergency Management in Linn County reported flash 
flooding near 33rd Ave SW and 6th St SW as well as on Wylie Blvd 
north of Johnson Ave NW. Between 1 and 3 inches of rain have fallen 
this morning. Additional rainfall amounts up to 0.5 inches are 
possible in the warned area. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Emergency management reported.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Cedar Rapids, Iowa City, West Branch, Marion, Coralville, North 
  Liberty, Hiawatha, Mount Vernon, Lisbon, Fairfax, Solon, Tiffin, 
  Ely, Walford, Springville, University Heights, Swisher, Oxford, 
  Shueyville and Bertram.

This includes the following highways...
	Interstate 80 in Iowa between mile markers 230 and 253.
	Interstate 380 between mile markers 1 and 24.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4204 9183 4204 9166 4204 9137 4176 9137
      4162 9137 4163 9183 4201 9183

FLASH FLOOD...OBSERVED

$$

Schreck
858 
WGUS73 KDVN 171818
FFSDVN

Flash Flood Statement
National Weather Service Quad Cities IA IL
118 PM CDT Wed Jun 17 2026

IAC103-113-171828-
/O.CAN.KDVN.FF.W.0022.000000T0000Z-260617T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Johnson IA-Linn IA-
118 PM CDT Wed Jun 17 2026

...FLASH FLOOD WARNING IS CANCELLED FOR JOHNSON AND SOUTHERN LINN 
COUNTIES...

The heavy rain has ended and flood waters have receded. Flooding is 
no longer expected to pose a threat. Please continue to heed 
remaining road closures.

A Flood Watch remains in effect until 700 PM CDT for portions of 
Illinois, Iowa, and northeast Missouri.

&&

LAT...LON 4204 9183 4204 9166 4204 9137 4176 9137
      4162 9137 4163 9183 4201 9183

$$

Schreck

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Jun 17, 6:48 AM CDT, 36 minutes earlier. Its key messages:

  • Slight/Enhanced Risk (level 2/3 of 5) for severe storms early this morning around sunrise, lasting through mid morning.The primary threat with these storms will be large to very large hail.
  • Late this morning and through the afternoon, much of the area will have a threat for more severe storms, with the whole area under a severe threat ranging from a Slight Risk (level 2 of 5) in our northwest to a Moderate Risk (level 4 of 5) in our extreme southeast/east.
  • High moisture content over the area will allow for heavy rainfall with any storms through today. Flash flooding will be possible in areas that see repeating rounds of storms, especially in areas that recently saw heavy rainfall. Flood Watch remains in effect for areas in West-Central Illinois.
  • Quiet weather will be seen through the second half of the work week, with the pattern becoming active again this weekend and beyond.
Area forecast discussion, Jun 17, 6:48 AM CDT, 36 minutes before
Area Forecast Discussion
National Weather Service Quad Cities IA IL
648 AM CDT Wed Jun 17 2026

.KEY MESSAGES...

- Slight/Enhanced Risk (level 2/3 of 5) for severe storms early
  this morning around sunrise, lasting through mid morning.The
  primary threat with these storms will be large to very large
  hail.

- Late this morning and through the afternoon, much of the area
  will have a threat for more severe storms, with the whole
  area under a severe threat ranging from a Slight Risk (level 2
  of 5) in our northwest to a Moderate Risk (level 4 of 5) in
  our extreme southeast/east.

- High moisture content over the area will allow for heavy
  rainfall with any storms through today. Flash flooding will be
  possible in areas that see repeating rounds of storms,
  especially in areas that recently saw heavy rainfall. Flood
  Watch remains in effect for areas in West-Central Illinois.

- Quiet weather will be seen through the second half of the
  work week, with the pattern becoming active again this weekend
  and beyond.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 215 AM CDT Wed Jun 17 2026

Severe weather is expected today as a seasonably strong system moves
through the region. This will bring two rounds of storms to eastern
Iowa, northwest Illinois, and northeast Missouri: a first round
in the morning hours (4-9 AM) and second round in the afternoon
hours (12-7 PM). Morning storms are anticipated to have a
primary threat of large hail and low damaging wind potential,
while afternoon storms will be capable of all hazards, including
tornadoes. In addition, heavy rain will lead to localized flash
flooding, especially in areas that see repeated rounds of
storms.

A strong shortwave will move from the Northern Plains into the Upper
Midwest this morning. Pressure heights are near or at the NAEFS
climatological minimum for mid-June, while winds aloft are near or
at their maximum. This can be seen in a strong (50-60 kts) zonal jet
at 500 mb sampled upstream with today's 00Z soundings. As this
system translates into the Upper Midwest early this morning,
southerly to southwesterly flow across the central Plains will
provide warm air advection and moisture, which will amplify with the
LLJ towards sunrise. As a result, dewpoints are forecast to rise
into the mid to upper 60s within a few hours after sunrise, creating
a sharp gradient between the northern and southern halves of
the CWA. Lift along this WAA wing will provide the focus for
morning convection, with showers and storms across the area.

For the morning, the greatest risk for severe storms is along and
south of Interstate 80, though there is some uncertainty given a
strong cap over the region. If storms are able to develop, shear
magnitude and direction suggests a mixed storm mode with multicell
and supercells storms. A favorable severe environment of high lapse
rates (7.5-8.5 degC/km) and up to 2000 J/kg of MUCAPE will support a
primary risk of large hail. In addition to the risk of large hail,
heavy rain will be possible with these these storms. This should be
a soaking rain this morning and flash flooding threat should be
limited, save for areas that have a long residence time with storms.
This would primarily occur with cells that move over the same areas,
as storms in this first round will be moving quickly towards the
east at 40-50 kts.

By mid- to late morning, these storms will move east into central
Illinois, giving the airmass time to recover. At this point, strong
southwesterly flow will continue to feed in moisture and
instability, providing the energy necessary for the second round of
storms. The greatest area of uncertainty is in how much recovery
time will be possible, as morning storms and showers could persist
longer than anticipated. If the atmosphere is able to recover
following morning storms, an environment favoring supercells will
develop, leading to the potential for all hazard severe
thunderstorms.

Around 12 PM, forcing along the cold front will plow into a region
of 2000 (north) to 4000 (south) J/kg of CAPE, providing the forcing
necessary for convective initiation. These storms will be fast
moving, with a storm motion of 50 kts to the east. Large hail and
damaging winds are possible with all storms. Tornado threat will be
more limited, with the best low level shear supporting the highest
tornado threat in west-central Illinois. These storms will exit into
central Illinois around 6-7 PM.

Once these storms move off to our east, CAA advection behind the
front will support westerly to northwesterly winds up to 20-25 mph,
leading to a breezy night.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 215 AM CDT Wed Jun 17 2026

Several pleasant, mainly dry days will follow our big system today.
This will lead to temperatures below normal for highs and lows
Thursday and Friday.  Dry air should keep any rain threat low,
though some energy skirting by aloft could bring some sprinkles
or even a tiny thunderstorm as early as Friday night.

Warm begins to spread northward again towards Saturday, as the flow
aloft shifts towards a more active zonal flow regime. Models remain
consistent in showing a warm front developing over the Midwest
Saturday night, and having at least one significant wave of
rain and thunderstorms/ potentially an MCS Sunday and Sunday
night. There is latitude differences in the latest
deterministic guidance, with the GFS shifting that axis a bit
south, and the EC and GEM maintaining a more northerly frontal
zone. Regardless, that will be the next period for us to focus
on for both heavy rainfall and a thunderstorm risk.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 648 AM CDT Wed Jun 17 2026

A severe, bowing line of storms is bearing down on KCID around
12Z and will quickly track southeast through KMLI and KBRL in
the 13Z to 14Z timeframe. There have been several reports of
50-60+ kt gusts with this line and expect that threat, along
with heavy rain, hail, lightning, and IFR conditions to
accompany the line of storms. Additional storms are following in
the wake of this line, so expect scattered to widespread storms
through early afternoon, with some strong to severe thunderstorm
development again possible at KMLI and KBRL in the early
afternoon with potential for damaging winds, hail, and possibly
tornadoes. Farther north, KDBQ will remain north of the severe
line of storms in more stratiform rain with embedded
thunderstorm activity and occasional lightning through around
18-19Z. Additional isolated storms are possible with the cold
frontal passage late this afternoon into early evening for KCID,
KDBQ, and KMLI, and a lower potential (less than 30%) at KBRL.
Winds remain breezy throughout the day outside of storms, with
breezy winds and VFR conditions behind storms this afternoon
and evening. Low-level wind shear develops at most terminals
again for a few hours this evening.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...Flood Watch through this evening for ILZ009-016>018.
MO...None.

&&

SHORT TERM...Ellingworth
LONG TERM...Ervin
AVIATION...NWS
Hazardous weather outlook, Jun 17, 3:21 AM CDT, 4 hours 3 minutes before
Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
321 AM CDT Wed Jun 17 2026

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-180830-
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-
321 AM CDT Wed Jun 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

The Wapsipinicon River is experiencing flooding. Please see the
latest Flood Statements and Flood Warnings for details.

A strong system will bring the potential for severe thunderstorms
today. A Moderate, level 4 of 5, risk is forecast for central
Illinois, with an Enhanced, level 3 of 5, risk of severe
thunderstorms south of Highway 30 and the remainder of the area
under a Slight, level 2 of 5, risk. The first round of thunderstorms
will continue through late morning today, with a primary risk of
large hail. After 12 PM, a second round of thunderstorms is expected
along and ahead of the cold front, with all severe weather hazards
possible, including tornadoes. Localized flash flooding will be
possible during both rounds, especially in areas that see multiple
rounds of storms.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

The next chance for thunderstorms will be Sunday and Sunday night.

.SPOTTER INFORMATION STATEMENT...
Spotter activation is expected this morning and this afternoon.

Ellingworth/Ervin

In the hours before

Local storm report, Jun 17, 6:58 AM CDT, 26 minutes before
Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
658 AM CDT Wed Jun 17 2026

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

0652 AM     Tstm Wnd Gst     1 ESE Walford           41.88N 91.83W
06/17/2026  M75 MPH          Linn               IA   Mesonet

&&

arg
Local storm report, Jun 17, 7:01 AM CDT, 23 minutes before
Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
701 AM CDT Wed Jun 17 2026

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

0657 AM     Tstm Wnd Gst     Cedar Rapids Municipali 41.88N 91.71W
06/17/2026  M66 MPH          Linn               IA   Public

&&

arg
Local storm report, Jun 17, 7:06 AM CDT, 18 minutes before
Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
706 AM CDT Wed Jun 17 2026

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

0701 AM     Tstm Wnd Gst     Cedar Rapids Municipali 41.88N 91.71W
06/17/2026  M78 MPH          Linn               IA   ASOS

&&

arg
Local storm report, Jun 17, 7:15 AM CDT, 9 minutes before
Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
715 AM CDT Wed Jun 17 2026

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

0711 AM     Tstm Wnd Gst     2 NW North Liberty      41.76N 91.62W
06/17/2026  E70 MPH          Johnson            IA   Public

&&

arg
Local storm report, Jun 17, 7:21 AM CDT, 3 minutes before
Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
721 AM CDT Wed Jun 17 2026

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

0714 AM     Tstm Wnd Gst     1 N North Liberty       41.75N 91.61W
06/17/2026  M64 MPH          Johnson            IA   Mesonet

&&

arg
Local storm report, Jun 17, 7:24 AM CDT, 0 minutes before
Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
724 AM CDT Wed Jun 17 2026

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

0716 AM     Rain             1 N Ely                 41.89N 91.59W
06/17/2026  M1.70 Inch       Linn               IA   Trained Spotter

&&

arg

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 17, 5:52 AM CDTSevere Thunderstorm WarningDVNJohnson, Louisa, Muscatine, Washington53 min
Jun 17, 6:09 AM CDTSevere Thunderstorm Warning Considerable damage threatDVNBenton, Iowa66 min
Jun 17, 6:45 AM CDTSevere Thunderstorm Warning Considerable damage threatDVNJohnson, Keokuk, Linn, Washington60 min
Jun 17, 7:08 AM CDTSevere Thunderstorm Warning Destructive damage threatDVNCedar, Johnson, Jones, Keokuk, Linn, Louisa and 2 more52 min
Jun 17, 7:17 AM CDTSevere Thunderstorm Warning Considerable damage threatDVNDes Moines, Henry, Jefferson, Keokuk, Louisa, Washington58 min
Jun 17, 7:35 AM CDTSevere Thunderstorm Warning Considerable damage threatDVNClinton, Jackson, Muscatine, Scott55 min
Jun 17, 7:55 AM CDTFlash Flood WarningDVNCedar, Iowa, Johnson, Jones, Keokuk, Linn and 3 more5 hr
Jun 17, 7:57 AM CDTSevere Thunderstorm Warning Considerable damage threatDVNDes Moines, Henry, Lee, Louisa, Van Buren63 min
Jun 17, 8:06 AM CDTSevere Thunderstorm WarningDVNJefferson, Lee, Van Buren39 min
Jun 17, 8:25 AM CDTFlash Flood WarningDVNCedar, Clinton, Muscatine, Scott5 hr
Jun 17, 8:43 AM CDTFlash Flood WarningDVNDes Moines, Henry, Jefferson3 hr
Jun 17, 8:43 AM CDTSevere Thunderstorm Warning Considerable damage threatDVNLee, Van Buren62 min
Jun 17, 10:22 AM CDTRiver Flood WarningDVNJohnson, Washington70 hr
Jun 17, 3:29 PM CDTSevere Thunderstorm WarningDVNLee61 min

Nearby

Flash Flood Warnings in Iowa, 2026Every flash flood 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.