Alert archive / Illinois / Tornado Warnings in 2026

Tornado Warning 92, NWS Quad Cities, IA

August 21, 2026Putnam County, Illinois

NWS Quad Cities, IA issued this tornado warning at Aug 21, 2026, 8:09 PM CDT for Putnam County, Illinois. It was in force for 21 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 21, 2026, 8:09 PM CDT (01:09 UTC)
Expired
Aug 21, 2026, 8:30 PM CDT
In force
21 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Putnam County, IL

The radar

The Chicago radar (KLOT), 104 km from the middle of the area, began a volume at 01:12 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 21, 2:57 PM CDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 1.2 hours before the alert went out and 110 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 2026-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3453 joules per kilogram.LCLEL10008507005003002001001 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 2026-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 89 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
3453 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
863 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
89 m²/s²
0-3 km storm-relative helicity
165 m²/s²
Significant tornado parameter
1.2
Supercell composite
7.8

Open this sounding in Storm Lab

The text

As transmitted.

127 
WFUS53 KDVN 220109
TORDVN
ILC155-220130-
/O.NEW.KDVN.TO.W.0092.260822T0109Z-260822T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Quad Cities IA/IL
809 PM CDT Fri Aug 21 2026

The National Weather Service in the Quad Cities has issued a

* Tornado Warning for...
  Northeastern Putnam County in north central Illinois...

* Until 830 PM CDT.

* At 804 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Mark, or over Hennepin, moving east at 15 mph.

  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...
  Granville and Mark around 810 PM CDT.

This also includes Donnelley DePue State Fish and Wildlife Area.
 
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.

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

&&

LAT...LON 4123 8932 4130 8934 4131 8929 4131 8928
      4132 8927 4132 8926 4131 8923 4131 8916
      4122 8916
TIME...MOT...LOC 0104Z 278DEG 7KT 4127 8928 

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

$$

Gross
2 follow-up statements
859 
WWUS53 KDVN 220121
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
821 PM CDT Fri Aug 21 2026

ILC155-220130-
/O.CON.KDVN.TO.W.0092.000000T0000Z-260822T0130Z/
Putnam IL-
821 PM CDT Fri Aug 21 2026

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR
NORTHEASTERN PUTNAM COUNTY...

At 821 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Granville, or near Hennepin, moving southeast at 10
mph.

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...
  Standard around 825 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.

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4128 8927 4129 8926 4130 8922 4130 8916
      4122 8916 4123 8927
TIME...MOT...LOC 0121Z 299DEG 9KT 4124 8923 

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

$$

Gross
765 
WWUS53 KDVN 220126 RRA
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
826 PM CDT Fri Aug 21 2026

ILC155-220135-
/O.EXP.KDVN.TO.W.0092.000000T0000Z-260822T0130Z/
Putnam IL-
826 PM CDT Fri Aug 21 2026

...THE TORNADO WARNING FOR NORTHEASTERN PUTNAM COUNTY WILL EXPIRE AT
830 PM CDT...

The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.  However, heavy rain is still possible with
this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for
north central Illinois.

&&

LAT...LON 4128 8927 4129 8926 4130 8922 4130 8916
      4122 8916 4123 8927
TIME...MOT...LOC 0125Z 278DEG 7KT 4124 8922 

$$

Gross

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 21, 5:45 PM CDT, 2 hours 24 minutes earlier. Its key messages:

  • Cold frontal passage will bring a risk of strong to severe storms through sunset.
  • Outside of yet another system centered around Wednesday, mainly dry conditions should be seen until late next week.
Area forecast discussion, Aug 21, 5:45 PM CDT, 2 hours 24 minutes before
Area Forecast Discussion
National Weather Service Quad Cities IA IL
545 PM CDT Fri Aug 21 2026

.KEY MESSAGES...

- Cold frontal passage will bring a risk of strong to severe
  storms through sunset.

- Outside of yet another system centered around Wednesday,
  mainly dry conditions should be seen until late next week.

&&

.SHORT TERM /THROUGH SATURDAY/...
Issued at 153 PM CDT Fri Aug 21 2026

At 18z the cool front was located roughly from KY51 southwest to
KIFA and near KEBS. Ahead of the front was a pre-frontal trof
running from roughly KOVS to near KDSM. Satellite has agitated
clouds along the front between KY51 and KDEH with showers a few
storms developing. There is a layer of low to mid level steep lapse
rates between the trof and front that will sweep through during the
late afternoon/evening with some showers or storms along the
pre-frontal trof. An associated upper level disturbance will
help to enhance the overall mesoscale lift and maintain the
showers/storms along the cool front.

The CAMs are struggling with what will happen late this
afternoon/evening due to the overall weak forcing.

Based on what has occurred so far from satellite/radar, some low end
convection will be seen along the pre-frontal trof. The stronger
convection, associated with the upper level disturbance, will be tied
to the passage of the cool front.

That being said, prime time for strong to severe storms looks to be
3 to 8 PM with the storms quickly decaying in the 8 to 10 PM time
frame.

The primary risks still look to be damaging winds and hail. However,
storm-scale interactions cannot fully rule out the potential of
brief spin-up tornadoes.

The relatively higher severe risk still looks to be along/east of
the Mississippi and the I-80 corridor on north.

After 10 PM quiet conditions will then be seen the remainder of the
night with slowly falling dew points as the cool front slowly exits
the area.

Seasonable temperatures will be seen on Tuesday with breezy
conditions developing around mid-day.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
Issued at 153 PM CDT Fri Aug 21 2026

Saturday night through Friday
Assessment...low (20-30%) confidence on rain around Wednesday

Northwest flow aloft will persist through the coming week. The best
chance for any rain looks to be tied to around Wednesday during the
passage of yet another cool front. However, this system will only
have the moisture associated with it. As a result, the model
consensus only has 20-30% chances for rain.

Prior to and after next Wednesday, there will be additional but
weaker upper level disturbances moving through in the flow aloft.
While an isolated shower or storm cannot be ruled out, over 90% of
the area will likely remain dry with near seasonable temperatures.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 541 PM CDT Fri Aug 21 2026

Isolated to scattered SHRA/TSRA will continue through 03z/22
with the better coverage along/east of the Mississippi and
generally north/east of KGBG. Once the cold front passes winds
will drop to under 10 knots overnight. Gusts up to 24 knots will
be possible after 16z/22 across eastern Iowa and northern
Illinois once the nocturnal inversion breaks.

&&

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

&&

SHORT TERM...08
LONG TERM...08
AVIATION...08
Hazardous weather outlook, Aug 21, 3:10 AM CDT, 16 hours 59 minutes before
Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
310 AM CDT Fri Aug 21 2026

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-220815-
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-
310 AM CDT Fri Aug 21 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

There will be the chance for strong to severe storms today,
especially for areas along and east of the Mississippi River. Storms
are expected to develop through the afternoon hours with damaging
winds and hail being the primary threats, with isolated tornadoes
being secondary. The Storm Prediction Center has highlighted areas
along and east of the river in a Slight Risk, or level 2 of 5, for
severe weather. A Marginal Risk, level 1 of 5, remains for areas
west.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Storm spotter activation is expected today, especially in Illinois
this afternoon and evening.

ERVIN

In the hours before

Special weather statement, Aug 21, 5:25 PM CDT, 2 hours 44 minutes before
Special Weather Statement
National Weather Service Quad Cities IA IL
525 PM CDT Fri Aug 21 2026

IAZ051>053-063>065-067-076>078-220100-
Benton-Linn-Jones-Iowa-Johnson-Cedar-Muscatine-Keokuk-Washington-
Louisa-
Including the cities of Vinton, Cedar Rapids, Anamosa, Marengo,
Iowa City, Tipton, Muscatine, Sigourney, Washington, and Wapello
525 PM CDT Fri Aug 21 2026

...Funnel clouds and weak, brief tornadoes possible through 8 PM...

Conditions are favorable for the development of funnel clouds, and
possibly brief, weak tornadoes.  The National Weather Service will
continue to closely monitor the situation, and may issue a
Tornado Warning if the threat increases. If you see a funnel cloud
or tornado, seek shelter indoors and then contact your local law
enforcement agency for relay to the National Weather Service.
Local storm report, Aug 21, 7:47 PM CDT, 22 minutes before
Preliminary Local Storm Report
National Weather Service Quad Cities IA IL
747 PM CDT Fri Aug 21 2026

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

0730 PM     Tstm Wnd Dmg     1 E Fulton              41.86N 90.15W
08/21/2026                   Whiteside          IL   Public

            Power lines down across the road in Fulton
            Illinois on Illinois 136 towards Clinton.
            Time estimated from radar.

&&

ALE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 7:22 PM CDTTornado Warning Tornado observedDVNPutnam23 min
Aug 21, 8:12 PM CDTFlash Flood WarningDVNBureau, Putnam4 hr
Aug 21, 8:13 PM CDTSevere Thunderstorm WarningDVNBureau, Henry, Rock Island, Whiteside34 min
Aug 21, 8:54 PM CDTSpecial Weather StatementDVNBureau, Henry, Mercer66 min
Aug 21, 9:22 PM CDTSevere Thunderstorm WarningDVNHenry23 min

Nearby

Tornado Warnings in Illinois, 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.