Severe Thunderstorm Warning 233, NWS Quad Cities, IA

Area Forecast Discussion
National Weather Service Quad Cities IA IL
227 PM CDT Fri Aug 7 2026

.KEY MESSAGES...

- A cold front will bring scattered showers and thunderstorms
  (30-50% coverage) to the area late this afternoon into the
  evening hours. A few of these storms could be severe with the
  primary hazards being gusty winds and locally heavy
  downpours.

- An active pattern keeps rain chances on the table through the
  middle of next week with plenty of dry hours in between, but
  muggy to oppressive humidity returns.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 158 PM CDT Fri Aug 7 2026

A line of thunderstorms continues to develop across central
Iowa early this afternoon. This line of storms is forecast to
move south southeastward along a CAPE gradient across central
and eastern Iowa this afternoon into this evening. There is a
severe thunderstorm watch in effect through 10 PM for area along
and west of a line from Manchester to Tipton to Wapello. Damaging
winds and heavy rain are the main threats. Storms are forecast
to exit the area prior to 6 UTC.

Later tonight, patchy fog is possible overnight as winds
becoming light with low abundant level moisture across the
area. Low temperatures are expected to be in the 60s. A cold
front is forecast to move across the area tonight and turn winds
to the west.

Winds are forecast to turn the south on Saturday with increasing
moisture during the afternoon and evening hours. High
temperatures on Saturday will be in the 80s across the area.

Another shortwave is forecast to move across the area Saturday
and bring chances of showers and thunderstorms to the area
mainly after midnight. Severe thunderstorms are possible
overnight. There is a Marginal (level 1 out of 5) Risk of
severe thunderstorms Saturday along and west of the Mississippi
River.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 116 AM CDT Fri Aug 7 2026

Sunday-Monday...As the two shortwaves quickly move to the
southeast, the deformation zone remain in place Sunday, but
PoPs should decrease to 30-50% with the lack of upper-level
dynamical support. The low pressure over the Central Plains is
also expected to stall out which will be an issue heading into
Sunday night as another subtle shortwave zooms across Wyoming
into South Dakota and Nebraska. A second LLJ is likely to
develop, spawning another round of showers and storms Sunday
night into Monday. This shortwave trough will also reinvigorate
the deformation zone and pull it northward. The increased
southwesterly flow, low-level WAA, and moisture advection could
lead to excessive heat developing, especially in our south where
clearing skies are more likely. Current LREF guidance has a
20-30% chance of heat indices exceeding 100 degrees south of
Interstate 80 Monday afternoon. Regardless though, dew points
are going to be in the 70s, possibly in the mid-to-upper 70s
(40-60% chance per 06.12z LREF guidance), making it feel muggy
to oppressive outside even with potential cloud cover.

Tuesday-Thursday...Multiple shortwaves passages will keep
precipitation chances around through the middle of next week, but
these repeated passages should slowly push the deformation zone
further south as high pressure eventually settles back in over
the region. There is general consensus among the ensembles that
a return to north-to-northeasterly flow in the low-levels
should erode away at the high dew points and temperatures,
returning to the area to seasonable conditions by the end of
next week.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1240 PM CDT Fri Aug 7 2026

In the wake of fog this morning, periods of MVFR ceilings
continue across the area at all TAF sites. A storm system is
forecast to move across the area later this afternoon into this
evening with low confidence in the exact timing and locations.
Used 3 to 4 hour prob30 window at each TAF site to account for
the timing of these storms. If storms do occur than MVFR
ceilings are possible in storms with periods of IFR to LIFR
visibilities in the strongest storms. Conditions are expected to
improve to VFR behind the storm but fog is possible tonight
with MVFR to IFR visibilities possible after 06 UTC with
conditions improving by 14 UTC Saturday. Southerly winds today
will shift to the northwest behind the front from west to east.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.

&&

SHORT TERM...Cousins
LONG TERM...Delaune
AVIATION...Cousins

Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
600 AM CDT Fri Aug 7 2026

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-081100-
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-
600 AM CDT Fri Aug 7 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

Dense fog will reduce visibility to a quarter mile or less at
times across portions of eastern Iowa and northeast Missouri
through the early morning commute.

Scattered thunderstorms (30% to 50% chance) are possible late
this afternoon into the overnight, mainly west of the
Mississippi River. Isolated severe storms with hail and
strong winds is possible along with locally heavy rain.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

Another round of scattered showers and thunderstorms are possible
Saturday night and Sunday. A few of these storms could turn
severe with gusty winds, hail and heavy downpours.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed late this afternoon and evening.

Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
428 PM CDT Fri Aug 7 2026

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

0415 PM     Tstm Wnd Dmg     Fairbank                42.64N 92.05W
08/07/2026                   Buchanan           IA   Emergency Mngr

            Multiple utility poles down in Fairbank.
            Possible tornado. Time estimated from radar.

&&

ALE

Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
430 PM CDT Fri Aug 7 2026

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

0415 PM     Hail             Fairbank                42.64N 92.05W
08/07/2026  M1.75 Inch       Buchanan           IA   Emergency Mngr

            Time estimated from radar.

&&

ALE

Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
434 PM CDT Fri Aug 7 2026

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

0418 PM     Tstm Wnd Gst     Fairbank                42.64N 92.05W
08/07/2026  M58 MPH          Buchanan           IA   Public

            PWS.

&&

Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
445 PM CDT Fri Aug 7 2026

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

0437 PM     Tstm Wnd Gst     2 SSW Three Elms County 42.42N 91.88W
08/07/2026  M55 MPH          Buchanan           IA   Public

            PWS.

&&