Severe Thunderstorm Warning 217, NWS Quad Cities, IA

Area Forecast Discussion
National Weather Service Quad Cities IA IL
248 PM CDT Fri Jul 3 2026

.KEY MESSAGES...

-  Extreme Heat Warning continues through this evening for the south,
   the other areas cloud debris and lingering precip should
   keep heat index readings below headline criteria. Still very
   humid and uncomfortable. Not as hot early next week with more
   seasonable temps.

-  Messy storm pattern through the weekend with several rounds
   of storms possible. But many dry hours embedded in with the
   storm chances as well.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 243 PM CDT Fri Jul 3 2026

The outflow boundary from last nights storm complex is now moving
back north and allowing the atmosphere to recover. The heat
headlines will remain in place with the 10 PM expiration time
looking reasonable.

The flood watch has been expanded in areal coverage down to Highway
34 in southeast Iowa and extended through 7 AM Saturday morning.

As the boundary moves back north, it will collide the other
boundaries across the area. Each boundary and the intersection of
boundaries will provide numerous foci for diurnal convection
development any time after 4 PM. Overall coverage will be isolated
to scattered (10-35%) through sunset with said convection slowly
decaying through midnight.

Late this afternoon storms will fire in eastern Nebraska and grow
upscale into another organized storm complex. The storm complex will
then move generally east across Iowa and arrive in eastern Iowa at
after midnight.

Thus rain chances will be low through 4 PM followed by an uptick
through sunset and then perhaps another lull. Depending upon where
the storm complex forms and moves tonight, there should be a general
uptick with rain chances after midnight.

Moisture levels in the atmosphere remain quite high so storms will
have plenty of moisture available to produce rain. Warm rain
processes have a 50-70% probability of coming into play so rainfall
rates in the stronger storms will potentially be high. Corfidi
vectors become perpendicular to each other and at times are opposed
to each other. This raises the potential for storms to repeat over
the same areas or move very slowly. If this occurs then rainfall
would have a high probability of being excessive.

As for the severe risk tonight, the better risk is the western half
of Iowa. Storms should be in a decaying mode when they arrive in
eastern Iowa. An isolated severe storm cannot be ruled out with
damaging winds and hail being the primary risks.

Saturday will likely be similar to Friday morning; a decaying storm
complex entering or over eastern Iowa that has new convection
developing along outflow boundaries. This scenario will likely be
seen through mid-morning followed by convection dissipating in the
late morning. Boundaries left over from the nocturnal convection
will provide numerous foci for diurnal development mid to late
afternoon Saturday. Like Friday, coverage will be low at 10-30
percent. There may be a couple of severe storms Saturday with
damaging wind and hail being the primary risks.

Heat and humidity will continue across the area on Saturday but peak
afternoon heat indices along/south of Highway 30 look to be 95 to
100. North of Highway 30, peak heat indices look to be 90 to 95.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 300 AM CDT Fri Jul 3 2026

Saturday night...there are signs of short wave energy and mid
level jet flux starting to angle the steering flow acrs the
upper Midwest more northwesterly. this process may form
nocturnal thunderstorms right overhead, just off to the
southwest, or north to northeast of the local CWA into Sunday
morning. Several models and ensembles support all three of these
scenarios and makes for high uncertainty at this juncture in
time. Will have to cover these chances with decent POPs and
await further runs for any changes.

Sunday...Not as hot and with a northwest flow upper wave overhead,
there will be the chance for isolated to widely sctrd showers and
storms popping up in the afternoon heating. High CAPE-low shear type
of scenario.

Quick look at next week, appears to be large/broad ridging regime
developing acrs much of the upper mid CONUS, meaning mainly dry and
seasonable for the home team through at least mid week.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1236 PM CDT Fri Jul 3 2026

Weak forcing and numerous outflow boundaries across eastern Iowa
and northern Illinois means isolated to scattered (10-30%
coverage) of SHRA/TSRA will be possible through sunset. After
02z/04 yet another organized storm complex will develop across
western Iowa and slowly move east through 12z/04. After 12z/04
the storm complex will slowly decay. Given the high moisture
levels in the atmosphere, IFR/LIFR conditions are possible for
any TSRA that impacts a TAF site.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Flood Watch through Saturday morning for IAZ040>042-051>053-
     063>065-067-076>078-087>089.
     Extreme Heat Warning until 10 PM CDT this evening for
     IAZ087>089-098-099.
IL...Extreme Heat Warning until 10 PM CDT this evening for ILZ025-
     026-034-035.
MO...Extreme Heat Warning until 10 PM CDT this evening for MOZ009-
     010.

&&

SHORT TERM...08
LONG TERM...12/08
AVIATION...08

Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
254 PM CDT Fri Jul 3 2026

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-042000-
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-
254 PM CDT Fri Jul 3 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...THIS AFTERNOON AND TONIGHT

The Extreme Heat Warning will continue through this evening
for areas generally along and south of an Ottumwa, Iowa to
Galesburg, Illinois line. Peak heat indices just over 100 are
expected.

The entire Outlook Area will be susceptible to rounds of
thunderstorms tonight. The potential for strong to severe storms
and flash flooding will also continue through this period. Most of
the area is in Slight Risk(Level 2 out of 5) tonight with
damaging winds the primary concern. Repeated storms producing
heavy rainfall at high rates will also have the capability to
produce flash flooding.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

There is a Marginal Risk(Level 1 out of 5) for severe weather on
Saturday for areas generally south and east of a Mount Pleasant
Iowa, to Quad Cities, to Princeton Illinois line.

Locally heavy rain and flash flooding will also continue to be a
threat on Saturday. The repeated rounds of heavy rain will produce
rises on some area creeks and tributary rivers, with a few
potentially reaching bankfull or even approach the flood stage
through early next week.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed at times today through Saturday.

Special Weather Statement
National Weather Service Quad Cities IA/IL
455 PM CDT Fri Jul 3 2026

IAZ051-052-063-064-032300-
Linn IA-Iowa IA-Benton IA-Johnson IA-
455 PM CDT Fri Jul 3 2026

...Strong thunderstorms will impact portions of southwestern Linn,
northeastern Iowa, southeastern Benton and northwestern Johnson
Counties through 600 PM CDT...

At 454 PM CDT, Doppler radar was tracking a couple strong
thunderstorm over northern Iowa County, including one near Marengo,
and the other 2 miles east of Ladora, both moving east at 15 mph.

HAZARD...Winds in excess of 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could cause minor tree limb damage and blow
         around unsecured objects. Minor damage to outdoor objects
         is possible.

Locations impacted include...
Cedar Rapids, Marengo, Williamsburg, Fairfax, Walford, Oxford,
Norway, Amana, Conroy, Middle Amana, South Amana, Homestead, West
Amana, Upper South Amana, East Amana, Genoa Bluff, Watkins, F.W. Kent
Park, High Amana, and Iowa County Fairgrounds.

This includes Interstate 80 in Iowa between mile markers 212 and 234.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is occurring and may lead to localized flooding.
Do not drive your vehicle through flooded roadways. Stay away from
flooded areas. Report any flooding to local law enforcement.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4168 9217 4181 9218 4199 9173 4166 9173
TIME...MOT...LOC 2154Z 248DEG 13KT 4175 9214

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

Friedlein

Special Weather Statement
National Weather Service Quad Cities IA/IL
513 PM CDT Fri Jul 3 2026

IAZ040>042-051>054-066-ILZ001-002-032330-
Jo Daviess IL-Stephenson IL-Clinton IA-Linn IA-Buchanan IA-
Delaware IA-Benton IA-Jackson IA-Dubuque IA-Jones IA-
513 PM CDT Fri Jul 3 2026

...Strong thunderstorms will impact portions of Jo Daviess,
Stephenson, northwestern Clinton, Linn, southeastern Buchanan,
Delaware, northeastern Benton, Jackson, Dubuque and Jones Counties
through 630 PM CDT...

At 512 PM CDT, Doppler radar was tracking scattered strong
thunderstorms across the U.S. Highway 30 to U.S. Highway 20
corridors in eastern Iowa and far northwest Illinois. Movement was
east at 35 mph.

HAZARD...Winds in excess of 40 mph and minor flooding.

SOURCE...Radar indicated.

IMPACT...Gusty winds could cause minor tree limb damage and blow
         around unsecured objects. Slowing or redirecting of traffic
         due to ponding or flowing water. Closure of waterfront
         access due to flooding.

Locations impacted include...
Cedar Rapids, Dubuque, Freeport, Anamosa, Vinton, Manchester, Galena,
Marion, Hiawatha, Mount Vernon, Asbury, Dyersville, Monticello,
Robins, Lena, Center Point, Bellevue, Cascade, Lisbon, and Fairfax.

This includes Interstate 380 between mile markers 12 and 45.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is occurring and may lead to localized flooding.
Do not drive your vehicle through flooded roadways.

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4265 9077 4263 9070 4252 9064 4251 9064
      4250 8940 4220 8940 4219 9031 4218 9033
      4186 9162 4186 9174 4214 9209 4265 9136
      4265 9090 4268 9090
TIME...MOT...LOC 2212Z 255DEG 29KT 4216 9136 4193 9164

MAX HAIL SIZE...<0.75 IN
MAX WIND GUST...40 MPH

Friedlein

Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
555 PM CDT Fri Jul 3 2026

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

0538 PM     Tstm Wnd Dmg     2 SE Scioto Mills       42.33N 89.64W
07/03/2026                   Stephenson         IL   Law Enforcement

            Tree fell and took down power lines.

&&

ALE

Special Weather Statement
National Weather Service Quad Cities IA/IL
615 PM CDT Fri Jul 3 2026

IAZ042-053-054-064>066-068-ILZ001-002-007-040000-
Carroll IL-Jo Daviess IL-Stephenson IL-Scott IA-Clinton IA-
Jackson IA-Dubuque IA-Cedar IA-Jones IA-Johnson IA-
615 PM CDT Fri Jul 3 2026

...Strong thunderstorms will impact portions of northwestern Carroll,
Jo Daviess, western Stephenson, northwestern Scott, Clinton, Jackson,
southeastern Dubuque, Cedar, southeastern Jones and northern Johnson
Counties through 700 PM CDT...

At 614 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near St. Donatus to Canton to near Olin to near
Tiffin. Movement was east at 30 mph.

HAZARD...Winds in excess of 40 mph, minor flooding and penny size
         hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could cause minor tree limb damage and blow
         around unsecured objects. Minor damage to outdoor objects
         is possible. Slowing or redirecting of traffic due to
         ponding or flowing water. Closure of waterfront access due
         to flooding.

Strong thunderstorms will be near...
  Iowa City, Galena, Stanwood, Coralville, North Liberty, University
  Heights, Oxford Junction, La Motte, Monmouth, and St. Donatus
  around 620 PM CDT.
  Fulton and Nashville around 625 PM CDT.
  Tipton, West Branch, Lost Nation, Andrew, and Hurstville around
  630 PM CDT.

Other locations in the path of these storms include Maquoketa,
Bellevue, Lowden, Toronto, Springbrook, Elizabeth and Schapville.

This includes the following highways...
 Interstate 80 in Iowa between mile markers 237 and 279.
 Interstate 380 near mile marker 1.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4250 8993 4236 8992 4211 9010 4190 9033
      4160 9095 4160 9136 4163 9181 4196 9115
      4251 9054
TIME...MOT...LOC 2314Z 275DEG 24KT 4239 9057 4217 9087 4196 9110 4167
9168

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

Gross