Alert archive / Iowa / Tornado Warnings in 2017

Tornado Warning 49, NWS Quad Cities, IA

July 21, 2017Cedar County, Johnson County, Muscatine County, Iowa

NWS Quad Cities, IA issued this tornado warning at Jul 21, 2017, 5:39 PM CDT for Cedar County, Johnson County, Muscatine County, Iowa. It was in force for 51 min. 1 report 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: Jul 21, 2017, 5:39 PM CDT (22:39 UTC)
Expired: Jul 21, 2017, 6:30 PM CDT
In force: 51 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.5 in

Counties Cedar County, IA, Johnson County, IA, Muscatine County, IA

The radar

The Quad Cities radar (KDVN), 73 km from the middle of the area, began a volume at 22:43 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

Time	Report	Where	Remark
Jul 21, 5:44 PM CDT	TORNADO	6 Ne Kalona, IA	REPORT DELAYED - POSSIBLE TORNADO MOVING NORTHEAST - FUNNEL CLOUD APPEARED TO BRIEFLY TOUCH DOWN THEN LIFTED BACK INTO THE STORM

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

The watch it was issued in

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

Issued	Product	Office	Lasted
Jul 21, 4:52 PM CDT	Severe Thunderstorm Watch	SPC	9 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.7 hours before the alert went out and 80 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 81 J/kg
Mixed-layer CIN: -302 J/kg
Mixed-layer LCL: 1173 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 125 m²/s²
0-3 km storm-relative helicity: 192 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

337 
WFUS53 KDVN 212239
TORDVN
IAC031-103-139-212330-
/O.NEW.KDVN.TO.W.0049.170721T2239Z-170721T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Quad Cities IA/IL
539 PM CDT FRI JUL 21 2017

The National Weather Service in the Quad Cities has issued a

* Tornado Warning for...
  Southwestern Cedar County in east central Iowa...
  Southeastern Johnson County in east central Iowa...
  Northwestern Muscatine County in east central Iowa...

* Until 630 PM CDT
    
* At 539 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Hills, or 7 miles southeast of Iowa City, moving
  east at 20 mph.

  HAZARD...Tornado and ping pong ball size hail. 

  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...
  West Liberty around 615 PM CDT. 

Other locations impacted by this tornadic thunderstorm include Hills
Access and Muscatine County Fairgrounds.

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 4152 9163 4160 9163 4165 9120 4149 9120
TIME...MOT...LOC 2239Z 272DEG 16KT 4156 9147 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

Gibbs

3 follow-up statements

002 
WWUS53 KDVN 212251
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
551 PM CDT FRI JUL 21 2017

IAC031-103-139-212330-
/O.CON.KDVN.TO.W.0049.000000T0000Z-170721T2330Z/
Cedar IA-Johnson IA-Muscatine IA-
551 PM CDT FRI JUL 21 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 630 PM CDT FOR
SOUTHWESTERN CEDAR...SOUTHEASTERN JOHNSON AND NORTHWESTERN MUSCATINE
COUNTIES...
    
At 551 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Lone Tree, or 9 miles south of West Branch, moving
east at 15 mph.

HAZARD...Tornado and ping pong ball size hail. 

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...
  West Liberty around 620 PM CDT. 

Other locations impacted by this tornadic thunderstorm include Hills
Access and Muscatine County Fairgrounds.

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.

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

&&

LAT...LON 4152 9157 4161 9157 4165 9120 4149 9120
TIME...MOT...LOC 2251Z 279DEG 13KT 4154 9141 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

Gibbs

014 
WWUS53 KDVN 212303
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
603 PM CDT FRI JUL 21 2017

IAC031-212312-
/O.CAN.KDVN.TO.W.0049.000000T0000Z-170721T2330Z/
Cedar IA-
603 PM CDT FRI JUL 21 2017

...THE TORNADO WARNING FOR SOUTHWESTERN CEDAR COUNTY IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore, the warning has been cancelled.

A severe thunderstorm watch remains in effect until midnight CDT for
east central Iowa.

LAT...LON 4151 9147 4160 9144 4159 9120 4149 9120
TIME...MOT...LOC 2302Z 292DEG 13KT 4151 9136 

$$

IAC103-139-212330-
/O.CON.KDVN.TO.W.0049.000000T0000Z-170721T2330Z/
Johnson IA-Muscatine IA-
603 PM CDT FRI JUL 21 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 630 PM CDT FOR
SOUTHEASTERN JOHNSON AND NORTHWESTERN MUSCATINE COUNTIES...
    
At 602 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Nichols, or 11 miles south of West Branch, moving
east at 15 mph.

HAZARD...Tornado and ping pong ball size hail. 

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...
  West Liberty around 615 PM CDT. 

Other locations impacted by this tornadic thunderstorm include
Muscatine County Fairgrounds.

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.

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

&&

LAT...LON 4151 9147 4160 9144 4159 9120 4149 9120
TIME...MOT...LOC 2302Z 292DEG 13KT 4151 9136 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

Gibbs

840 
WWUS53 KDVN 212312
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
612 PM CDT FRI JUL 21 2017

IAC103-212320-
/O.CAN.KDVN.TO.W.0049.000000T0000Z-170721T2330Z/
Johnson IA-
612 PM CDT FRI JUL 21 2017

...THE TORNADO WARNING FOR SOUTHEASTERN JOHNSON COUNTY IS
CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved east 
out of the warned area. Therefore, the warning has been cancelled.

A severe thunderstorm watch remains in effect until midnight CDT for
east central Iowa.

LAT...LON 4160 9137 4160 9130 4159 9130 4159 9120
      4149 9120 4150 9137
TIME...MOT...LOC 2310Z 272DEG 16KT 4151 9131 

$$

IAC139-212330-
/O.CON.KDVN.TO.W.0049.000000T0000Z-170721T2330Z/
Muscatine IA-
612 PM CDT FRI JUL 21 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 630 PM CDT FOR
NORTHWESTERN MUSCATINE COUNTY...
    
At 610 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Nichols, or 11 miles south of West Branch, moving
east at 20 mph.

HAZARD...Tornado and ping pong ball size hail. 

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. 

Locations impacted include...  
Nichols.

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.

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

&&

LAT...LON 4160 9137 4160 9130 4159 9130 4159 9120
      4149 9120 4150 9137
TIME...MOT...LOC 2310Z 272DEG 16KT 4151 9131 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

12

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 20, 7:05 PM CDT	Severe Thunderstorm Warning	DVN	Des Moines, Henry	40 min
Jul 20, 7:37 PM CDT	Severe Thunderstorm Warning	DVN	Henry, Jefferson	53 min
Jul 20, 7:56 PM CDT	Flash Flood Warning	DVN	Henry, Jefferson	6 hr
Jul 20, 8:27 PM CDT	Severe Thunderstorm Warning	DVN	Henry, Jefferson	46 min
Jul 20, 8:45 PM CDT	Severe Thunderstorm Warning	DVN	Louisa, Muscatine	31 min
Jul 20, 8:58 PM CDT	Flash Flood Warning	DVN	Henry, Jefferson, Louisa, Muscatine, Washington	6 hr
Jul 20, 9:44 PM CDT	Severe Thunderstorm Warning	DVN	Muscatine, Scott	46 min
Jul 20, 9:46 PM CDT	Severe Thunderstorm Warning	DVN	Jefferson, Keokuk, Washington	30 min
Jul 20, 10:13 PM CDT	Severe Thunderstorm Warning	DVN	Clinton, Scott	45 min
Jul 20, 10:39 PM CDT	Severe Thunderstorm Warning	DVN	Clinton, Scott	35 min
Jul 20, 11:39 PM CDT	Severe Thunderstorm Warning	DVN	Benton, Iowa, Keokuk	27 min
Jul 21, 12:40 AM CDT	Special Weather Statement	DVN	Cedar, Johnson, Muscatine	65 min
Jul 21, 1:27 AM CDT	Special Weather Statement	DVN	Scott	63 min
Jul 21, 5:10 AM CDT	Special Weather Statement	DVN	Buchanan, Cedar, Jones, Linn	65 min
Jul 21, 2:56 PM CDT	River Flood Watch	DVN	Delaware, Jones	67 hr
Jul 21, 2:56 PM CDT	River Flood Watch	DVN	Jackson	4 days
Jul 21, 2:56 PM CDT	River Flood Watch	DVN	Buchanan, Linn	5 days
Jul 21, 3:51 PM CDT	Severe Thunderstorm Warning	DVN	Iowa, Johnson, Washington	54 min
Jul 21, 4:39 PM CDT	Severe Thunderstorm Warning	DVN	Iowa, Johnson	66 min
Jul 21, 4:49 PM CDT	Tornado Warning	DVN	Johnson	56 min
Jul 21, 5:01 PM CDT	Severe Thunderstorm Warning	DVN	Cedar, Jones, Linn	59 min
Jul 21, 5:16 PM CDT	Flash Flood Warning	DVN	Cedar, Johnson, Jones, Linn	6 hr
Jul 21, 5:24 PM CDT	Severe Thunderstorm Warning	DVN	Dubuque	37 min
Jul 21, 6:10 PM CDT	Tornado Warning	DVN	Muscatine	50 min
Jul 21, 6:50 PM CDT	Special Weather Statement	DVN	Clinton, Scott	55 min

Nearby

Tornado Warnings in Iowa, 2017 Every tornado warning in 2017 Tornadoes in 2017

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.