Alert archive / Iowa / Tornado Warnings in 2026

Tornado Warning 81, NWS Quad Cities, IA

August 10, 2026Delaware County, Iowa

NWS Quad Cities, IA issued this tornado warning at Aug 10, 2026, 9:02 PM CDT for Delaware County, Iowa. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 10, 2026, 9:02 PM CDT (02:02 UTC)
Expired
Aug 10, 2026, 9:45 PM CDT
In force
43 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Delaware County, IA

The radar

The Quad Cities radar (KDVN), 114 km from the middle of the area, began a volume at 02:04 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this tornado warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

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 00:00Z, 2.0 hours before the alert went out and 118 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 2026-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4334 joules per kilogram.LCLLFCEL10008507005003002001001 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 2026-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 71 square meters per square second.193958Sfc1 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
4334 J/kg
Mixed-layer CIN
-25 J/kg
Mixed-layer LCL
919 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
71 m²/s²
0-3 km storm-relative helicity
314 m²/s²
Significant tornado parameter
4.6
Supercell composite
37.0

Open this sounding in Storm Lab

The text

As transmitted.

331 
WFUS53 KDVN 110202
TORDVN
IAC055-110245-
/O.NEW.KDVN.TO.W.0081.260811T0202Z-260811T0245Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Quad Cities IA/IL
902 PM CDT Mon Aug 10 2026

The National Weather Service in the Quad Cities has issued a

* Tornado Warning for...
  Southwestern Delaware County in northeastern Iowa...

* Until 945 PM CDT.

* At 901 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Ryan, or 8 miles south of Manchester, and is
  nearly stationary.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Ryan around 905 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4234 9157 4242 9156 4244 9144 4231 9145
TIME...MOT...LOC 0201Z 258DEG 3KT 4237 9152 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Ervin
5 follow-up statements
627 
WWUS53 KDVN 110211
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
911 PM CDT Mon Aug 10 2026

IAC055-110245-
/O.CON.KDVN.TO.W.0081.000000T0000Z-260811T0245Z/
Delaware IA-
911 PM CDT Mon Aug 10 2026

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 945 PM CDT FOR
SOUTHWESTERN DELAWARE COUNTY...

At 911 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Ryan, or 8 miles south of Manchester, and is nearly
stationary.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Ryan around 915 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4234 9155 4241 9154 4244 9144 4233 9145
TIME...MOT...LOC 0211Z 258DEG 3KT 4237 9151 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

Ervin
129 
WWUS53 KDVN 110217
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
917 PM CDT Mon Aug 10 2026

IAC055-110245-
/O.CON.KDVN.TO.W.0081.000000T0000Z-260811T0245Z/
Delaware IA-
917 PM CDT Mon Aug 10 2026

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 945 PM CDT FOR
SOUTHWESTERN DELAWARE COUNTY...

At 917 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Ryan, or 8 miles south of Manchester, and is nearly
stationary.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Ryan around 925 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4234 9155 4241 9154 4244 9144 4233 9145
TIME...MOT...LOC 0217Z 258DEG 3KT 4237 9150 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

Ervin
557 
WWUS53 KDVN 110227
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
927 PM CDT Mon Aug 10 2026

IAC055-110245-
/O.CON.KDVN.TO.W.0081.000000T0000Z-260811T0245Z/
Delaware IA-
927 PM CDT Mon Aug 10 2026

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 945 PM CDT FOR
SOUTHWESTERN DELAWARE COUNTY...

At 927 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Ryan, or 7 miles south of Manchester, and is nearly
stationary.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
southwestern Delaware County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4234 9152 4240 9152 4242 9144 4233 9145
TIME...MOT...LOC 0227Z 260DEG 4KT 4237 9148 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

Ervin
718 
WWUS53 KDVN 110231
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
931 PM CDT Mon Aug 10 2026

IAC055-110245-
/O.CON.KDVN.TO.W.0081.000000T0000Z-260811T0245Z/
Delaware IA-
931 PM CDT Mon Aug 10 2026

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 945 PM CDT FOR
SOUTHWESTERN DELAWARE COUNTY...

At 931 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Ryan, or 7 miles south of Manchester, and is nearly
stationary.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
southwestern Delaware County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4234 9152 4240 9152 4242 9144 4233 9145
TIME...MOT...LOC 0231Z 260DEG 4KT 4238 9148 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

Ervin
908 
WWUS53 KDVN 110236
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
936 PM CDT Mon Aug 10 2026

IAC055-110245-
/O.EXP.KDVN.TO.W.0081.000000T0000Z-260811T0245Z/
Delaware IA-
936 PM CDT Mon Aug 10 2026

...THE TORNADO WARNING FOR SOUTHWESTERN DELAWARE COUNTY WILL EXPIRE
AT 945 PM CDT...

The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
the Quad Cities.

&&

LAT...LON 4234 9152 4240 9152 4242 9144 4233 9145
TIME...MOT...LOC 0235Z 258DEG 3KT 4238 9148 

$$

Ervin

What forecasters said that day

The local office's own words before this tornado 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 tornado warning went out at Aug 10, 6:37 PM CDT, 2 hours 25 minutes earlier. Its key messages:

  • There is a chance of severe storms this afternoon/evening mainly east of the Mississippi where there is a slight, level 2 out of 5, risk of severe storms. The primary risk is damaging winds. Brief tornadoes are a secondary risk.
  • A QLCS, likely severe, will impact areas along/north of I-80 Tuesday morning. Damaging wind is the primary risk with a secondary risk of brief spin-up tornadoes. Much of the area is in a slight to enhanced, levels 2 and 3 out of 5, risk for Tuesday.
  • A heat advisory has been issued for areas along/south of an Ottumwa, IA to Galesburg, IL line. Depending upon storm evolution Tuesday, this headline may need to be extended further north.
Area forecast discussion, Aug 10, 6:37 PM CDT, 2 hours 25 minutes before
Area Forecast Discussion
National Weather Service Quad Cities IA IL
637 PM CDT Mon Aug 10 2026

.KEY MESSAGES...

- There is a chance of severe storms this afternoon/evening
  mainly east of the Mississippi where there is a slight, level
  2 out of 5, risk of severe storms. The primary risk is
  damaging winds. Brief tornadoes are a secondary risk.

- A QLCS, likely severe, will impact areas along/north of I-80
  Tuesday morning. Damaging wind is the primary risk with a
  secondary risk of brief spin-up tornadoes. Much of the area is
  in a slight to enhanced, levels 2 and 3 out of 5, risk for
  Tuesday.

- A heat advisory has been issued for areas along/south of an
  Ottumwa, IA to Galesburg, IL line. Depending upon storm
  evolution Tuesday, this headline may need to be extended
  further north.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 157 PM CDT Mon Aug 10 2026

A convectively induced vort max continues to move east across Iowa
and will generate diurnal showers and storms along/east of the
Mississippi through the evening. With a boundary present and high
CAPE values building in the atmosphere, isolated to scattered severe
storms will be possible with the primary risk being damaging winds.
Brief spin-up tornadoes are a secondary risk.

Once storms dissipate this evening a period of quiet but very muggy
conditions will be seen until an approaching storm complex arrives
around sunrise Tuesday.

Tuesday morning will be interesting.

Data so far indicates that the Tuesday morning storm complex will
likely be a QLCS. Damaging winds, potentially over 70 mph, will
be the primary risk. A secondary risk will be brief spin-up
tornadoes. Right now areas along/north of I-80 appear to have the
higher risk of severe storms.

A fairly significant cold pool should be generated from the storm
complex which may bring some relief to the very humid conditions
across the northern half of the area Tuesday. However, the cold pool
and associated outflow boundary will then provide the focus for
potential diurnal storm development Tuesday afternoon.

Further south, hot and humid conditions will be seen. A heat
advisory has been issued for areas along/south of an Ottumwa, IA to
Galesburg, IL line. Depending upon how the Tuesday morning storms
develop/evolve, the heat headline may or may not need to be extended
further north.

If diurnal storms develop Tuesday afternoon they will dissipate
shortly after sunset leaving another muggy night for the area.

There are questions regarding late Tuesday night as another
disturbance moves around the edge of the heat dome. This disturbance
could initiate another storm complex that arrives in the area around
sunrise Wednesday.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 255 AM CDT Mon Aug 10 2026

Tuesday...May initially be active if the Monday night-Tue morning
shortwave and MCS verifies, but after that feature exits the rest of
Tue and Tue night may be mainly dry or at risk for only an isolated
storm. Current NBM loaded temps and DPTs are hot and very humid for
Tuesday and easily supportive of heat headlines. But again there is
much uncertainty on convective trends, and cloud debris/storm
outflow interfering with the ambient temps and how much afternoon
time there would be for recovery. Will still message the potential
but make heat headline issuance a day by day process for now.

Wednesday through Sunday...Medium range ensembles and upper jet
patterns show the main upper ridge bulge trying to press it's way
eastward acrs the southern plains and low to mid MS RVR Valley mid
to late week. This process may try to shunt the main storm track
more off just to the north of the local area, or if it stalls some
keep us in the bullseye of continued daily ring of fire late week
and even into the weekend. The temperature battle will continue as
well with LLVL baroclinicity and thermal ribbon wavering acrs the
region for high heat or not so bad depending on the daily flux. Will
keep the idea if this pattern holds, there could be quite a bit of
rainfall build up over the week from the west central plains, acrs
IA/IL and over to the eastern OH RVR Valley. It's still early, but
currently Thu night looks like a potentail heavy rainfall MCS night
in the area especially south of I-80.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 637 PM CDT Mon Aug 10 2026

Mostly VFR conditions were observed over the area early this
evening, with some isolated MVFR ceilings seen near DBQ.
Speaking of DBQ, there may be some isolated storms this evening
there, but confidence is pretty low on them occurring, given
the spread among the models, so used a PROB30 group there.

The main focus for this TAF set remains on a thunderstorm
complex that's expected to move through the northern portions of
the area near/after sunrise Tuesday morning. DBQ and CID are
likely to be impacted by this complex, and the storms could be
pretty strong, possibly packing winds to around 40 to 50 knots.
With this said, we've opted for TEMPO groups to highlight the
most likely timing of the storms. If this storm moves overhead,
expect IFR to possibly LIFR conditions (mainly from visibility
reductions) for a time. Once the storms move out, the remainder
of the TAF period should be dry, with southerly flow around 5
to 10 knots.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Heat Advisory from noon to 8 PM CDT Tuesday for IAZ087>089-098-
     099.
IL...Heat Advisory from noon to 8 PM CDT Tuesday for ILZ025-026-034-
     035.
MO...Heat Advisory from noon to 8 PM CDT Tuesday for MOZ009-010.

&&

SHORT TERM...08
LONG TERM...12
AVIATION...Schultz
Hazardous weather outlook, Aug 10, 2:26 PM CDT, 6 hours 36 minutes before
Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
226 PM CDT Mon Aug 10 2026

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-111930-
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-
226 PM CDT Mon Aug 10 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

Severe thunderstorms are possible this afternoon and evening.
Damaging winds will be the primary risk with hail and brief spin-
up tornadoes a secondary risk. There is a slight, level 2 out of
5, risk for severe storms north of a Sigourney, Iowa to Galesburg,
Illinois line. A marginal, level 1 out of 5, risk for severe
storms exists for the rest of the area.

Locally heavy rainfall and flooding will be possible in areas with
repeated storm activity.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

A storm complex, likely severe, will impact areas mainly
along and north of Interstate 80 Tuesday morning. Damaging winds,
potentially over 70 mph, will be the primary risk. Brief spin-up
tornadoes will be a secondary risk. Much of the area is in a
slight to enhanced, levels 2 and 3 out of 5, risk for severe
storms.

Boundaries from the Tuesday morning storms will provide the focus
for new storm development Tuesday afternoon and evening. Some of
these storms could be severe.

A heat advisory has been issued for areas along and south of an
Ottumwa, Iowa to Galesburg, Illinois line Tuesday afternoon and
evening.

Rounds of strong to severe storms will again be possible Wednesday
as the area continues to lay under an active storm track. There is
a marginal, level 1 out of 5, risk for severe weather for the
outlook Area. Locally heavy rain and flooding will also be a
concern.

There will continue to be an almost daily chance for thunderstorms
into the upcoming weekend.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is possible this afternoon and evening for
areas east of the Mississippi. Spotter activation is likely
Tuesday morning.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 5:08 AM CDTSpecial Weather StatementDVNBenton37 min
Aug 11, 6:53 AM CDTSevere Thunderstorm WarningDVNBenton, Buchanan, Linn52 min
Aug 11, 7:09 AM CDTSevere Thunderstorm WarningDVNBenton, Buchanan, Delaware, Jones, Linn81 min
Aug 11, 7:11 AM CDTSevere Thunderstorm Warning Destructive damage threatDVNBuchanan, Delaware, Jones, Linn49 min
Aug 11, 7:15 AM CDTTornado WarningDVNBuchanan, Delaware45 min
Aug 11, 7:33 AM CDTSevere Thunderstorm Warning Considerable damage threatDVNDubuque, Jackson57 min
Aug 11, 7:36 AM CDTTornado WarningDVNDelaware, Dubuque39 min
Aug 11, 7:59 AM CDTSevere Thunderstorm Warning Considerable damage threatDVNClinton, Jackson, Jones61 min
Aug 11, 8:01 AM CDTTornado WarningDVNClinton, Jackson44 min
Aug 11, 8:20 AM CDTSevere Thunderstorm Warning Considerable damage threatDVNClinton, Scott43 min
Aug 11, 8:29 AM CDTTornado WarningDVNClinton20 min
Aug 11, 8:38 AM CDTTornado WarningDVNScott23 min
Aug 11, 8:54 AM CDTSevere Thunderstorm WarningDVNScott81 min

Nearby

Tornado Warnings in Iowa, 2026Every tornado warning in 2026Tornadoes 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.