Alert archive / Iowa / Tornado Warnings in 2017

Tornado Warning 29, NWS Quad Cities, IA

May 17, 20175 counties in Iowa

NWS Quad Cities, IA issued this tornado warning at May 17, 2017, 3:55 PM CDT for 5 counties in Iowa. It was in force for 50 min. 8 reports 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: May 17, 2017, 3:55 PM CDT (20:55 UTC)
Expired: May 17, 2017, 4:45 PM CDT
In force: 50 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.5 in

Counties Des Moines County, IA, Henry County, IA, Lee County, IA, Louisa County, IA, Van Buren County, IA

The radar

The Quad Cities radar (KDVN), 106 km from the middle of the area, began a volume at 20:56 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
May 17, 3:56 PM CDT	TSTM WND DMG	Farmington, IA	BRANCHES DOWN
May 17, 3:56 PM CDT	HAIL 0.25	Farmington, IA	TIME ESTIMATED - PEA TO DIME SIZE HAIL DURING STORM
May 17, 4:11 PM CDT	HAIL 0.25	1 Nnw Mount Pleasant, IA	PEA TO DIME SIZE HAIL
May 17, 4:20 PM CDT	HAIL 0.5	Mount Pleasant, IA
May 17, 4:20 PM CDT	HAIL 1.75	Mount Pleasant, IA	VIA SOCIAL MEDIA - TIME ESTIMATED
May 17, 4:28 PM CDT	HAIL 1.25	Mount Union, IA
May 17, 4:30 PM CDT	TSTM WND DMG	2 W Yarmouth, IA	TIME IS ESTIMATED - LARGE TREE BRANCH APPROX 18 FEET LONG WAS TORN OFF TREE
May 17, 4:32 PM CDT	TSTM WND DMG	2 W Yarmouth, IA	RFD OF THUNDERSTORM BROUGHT DOWN TREE BRANCHES.

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
May 17, 3:44 PM CDT	Tornado Watch	SPC	9 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 8.9 hours before the alert went out and 112 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: 103 J/kg
Mixed-layer CIN: -348 J/kg
Mixed-layer LCL: 1223 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 84 m²/s²
0-3 km storm-relative helicity: 79 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

994 
WFUS53 KDVN 172055
TORDVN
IAC057-087-111-115-177-172145-
/O.NEW.KDVN.TO.W.0029.170517T2055Z-170517T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Quad Cities IA/IL
355 PM CDT WED MAY 17 2017

The National Weather Service in the Quad Cities has issued a

* Tornado Warning for...
  Henry County in southeastern Iowa...
  Northwestern Des Moines County in southeastern Iowa...
  Southeastern Van Buren County in southeastern Iowa...
  Southwestern Louisa County in southeastern Iowa...
  Northwestern Lee County in southeastern Iowa...

* Until 445 PM CDT
    
* At 354 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Donnellson, or 16 miles east of Keosauqua, moving
  northeast at 45 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...
  St. Paul and Pilot Grove around 405 PM CDT. 
  Salem around 410 PM CDT. 
  Lowell around 415 PM CDT. 
  Mount Pleasant and New London around 420 PM CDT. 
  Mount Union around 435 PM CDT. 
  Winfield, Morning Sun and Wyman around 440 PM CDT. 
  Amber around 445 PM CDT. 

Other locations impacted by this tornadic thunderstorm include Henry
County Fairgrounds, Charleston, Mt Hamill, Oakland Mills, Geode State
Park, Elrick Junction, Oakland Mills Park, Mount Pleasant Municipal
Arpt, Lee County Fairgrounds and Shimek State Forest.

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 4065 9180 4116 9151 4116 9148 4120 9149
      4126 9145 4112 9110 4055 9156
TIME...MOT...LOC 2054Z 207DEG 39KT 4069 9165 

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

$$

12

4 follow-up statements

725 
WWUS53 KDVN 172105
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
405 PM CDT WED MAY 17 2017

IAC177-172113-
/O.CAN.KDVN.TO.W.0029.000000T0000Z-170517T2145Z/
Van Buren IA-
405 PM CDT WED MAY 17 2017

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

A tornado watch remains in effect until 1100 PM CDT for southeastern
Iowa.

LAT...LON 4072 9172 4079 9172 4116 9151 4116 9148
      4121 9149 4126 9145 4112 9110 4066 9147
TIME...MOT...LOC 2103Z 205DEG 40KT 4080 9159 

$$

IAC057-087-111-115-172145-
/O.CON.KDVN.TO.W.0029.000000T0000Z-170517T2145Z/
Henry IA-Des Moines IA-Louisa IA-Lee IA-
405 PM CDT WED MAY 17 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 445 PM CDT FOR HENRY...
NORTHWESTERN DES MOINES...SOUTHWESTERN LOUISA AND NORTHWESTERN LEE
COUNTIES...
    
At 403 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Pilot Grove, or 11 miles south of Mount Pleasant,
moving northeast at 45 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...
  Lowell around 410 PM CDT. 
  Mount Pleasant and New London around 420 PM CDT. 
  Mount Union around 430 PM CDT. 
  Winfield around 435 PM CDT. 
  Morning Sun and Wyman around 440 PM CDT. 

Other locations impacted by this tornadic thunderstorm include Henry
County Fairgrounds, Mt Hamill, Oakland Mills, Geode State Park,
Elrick Junction, Oakland Mills Park, Mount Pleasant Municipal Arpt,
Houghton, Water Works Park and Stephenson Park.

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 4072 9172 4079 9172 4116 9151 4116 9148
      4121 9149 4126 9145 4112 9110 4066 9147
TIME...MOT...LOC 2103Z 205DEG 40KT 4080 9159 

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

$$

12

805 
WWUS53 KDVN 172121
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
421 PM CDT WED MAY 17 2017

IAC111-172130-
/O.CAN.KDVN.TO.W.0029.000000T0000Z-170517T2145Z/
Lee IA-
421 PM CDT WED MAY 17 2017

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

A tornado watch remains in effect until 1100 PM CDT for southeastern
Iowa.

LAT...LON 4090 9160 4092 9164 4116 9151 4116 9148
      4121 9149 4126 9145 4112 9110 4081 9136
TIME...MOT...LOC 2120Z 207DEG 39KT 4097 9148 

$$

IAC057-087-115-172145-
/O.CON.KDVN.TO.W.0029.000000T0000Z-170517T2145Z/
Henry IA-Des Moines IA-Louisa IA-
421 PM CDT WED MAY 17 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 445 PM CDT FOR EASTERN
HENRY...NORTHWESTERN DES MOINES AND SOUTHWESTERN LOUISA COUNTIES...
    
At 420 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Mount Pleasant, moving northeast at 45 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...
  Mount Union around 430 PM CDT. 
  Winfield around 435 PM CDT. 
  Morning Sun and Wyman around 440 PM CDT. 

Other locations impacted by this tornadic thunderstorm include Henry
County Fairgrounds, Water Works Park, Oakland Mills, Pleasant Grove,
Cairo, Oakland Mills Park, Virginia Grove Recreation Area, Mount
Pleasant Municipal Arpt, Marsh and Garland.

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 4090 9160 4092 9164 4116 9151 4116 9148
      4121 9149 4126 9145 4112 9110 4081 9136
TIME...MOT...LOC 2120Z 207DEG 39KT 4097 9148 

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

$$

12

987 
WWUS53 KDVN 172131
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
431 PM CDT WED MAY 17 2017

IAC057-087-115-172145-
/O.CON.KDVN.TO.W.0029.000000T0000Z-170517T2145Z/
Henry IA-Des Moines IA-Louisa IA-
431 PM CDT WED MAY 17 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 445 PM CDT FOR
NORTHEASTERN HENRY...NORTHWESTERN DES MOINES AND SOUTHWESTERN LOUISA
COUNTIES...
    
At 429 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Mount Union, or 10 miles northeast of Mount 
Pleasant, moving northeast at 45 mph. This storm has produced large 
hail earlier in the Mount Pleasant area.

HAZARD...Tornado and golf 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...
  Morning Sun around 440 PM CDT. 
  Amber around 445 PM CDT. 

Other locations impacted by this tornadic thunderstorm include
Pleasant Grove, Cairo, Virginia Grove Recreation Area, Marsh,
Garland, Yarmouth and Elrick Junction.

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 4104 9157 4116 9151 4116 9148 4121 9149
      4126 9145 4112 9110 4090 9129
TIME...MOT...LOC 2129Z 217DEG 38KT 4104 9138 

TORNADO...RADAR INDICATED
HAIL...1.75IN

$$

12

273 
WWUS53 KDVN 172145
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
445 PM CDT WED MAY 17 2017

IAC057-087-115-172154-
/O.EXP.KDVN.TO.W.0029.000000T0000Z-170517T2145Z/
Henry IA-Des Moines IA-Louisa IA-
445 PM CDT WED MAY 17 2017

...THE TORNADO WARNING FOR NORTHEASTERN HENRY...NORTHWESTERN DES
MOINES AND SOUTHWESTERN LOUISA COUNTIES WILL EXPIRE AT 445 PM CDT...
        
The storm which prompted the warning has moved north just out of the 
area. Therefore, the warning will be allowed to expire.

A tornado watch remains in effect until 1100 PM CDT for southeastern
Iowa.

LAT...LON 4104 9157 4116 9151 4116 9148 4121 9149
      4126 9145 4112 9110 4090 9129
TIME...MOT...LOC 2144Z 207DEG 39KT 4118 9129 

$$

12

The office that day

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

Issued	Product	Office	Counties	Lasted
May 17, 1:23 AM CDT	Special Weather Statement	DVN	Benton, Buchanan, Delaware, Iowa, Johnson, Jones and 3 more	37 min
May 17, 8:50 AM CDT	Special Weather Statement	DVN	Scott	25 min
May 17, 3:16 PM CDT	Severe Thunderstorm Warning	DVN	Benton, Buchanan, Linn	43 min
May 17, 3:36 PM CDT	Severe Thunderstorm Warning	DVN	Delaware, Dubuque, Jones, Linn	54 min
May 17, 3:38 PM CDT	Tornado Warning	DVN	Jefferson, Keokuk, Washington	52 min
May 17, 3:45 PM CDT	Severe Thunderstorm Warning	DVN	Des Moines, Henry, Lee, Van Buren	30 min
May 17, 3:49 PM CDT	Tornado Warning	DVN	Henry, Jefferson, Van Buren, Washington	41 min
May 17, 4:23 PM CDT	Severe Thunderstorm Warning	DVN	Iowa, Johnson, Washington	44 min
May 17, 4:40 PM CDT	Tornado Warning	DVN	Des Moines, Henry, Louisa, Muscatine	50 min
May 17, 5:03 PM CDT	Severe Thunderstorm Warning	DVN	Benton, Iowa, Keokuk	57 min
May 17, 5:24 PM CDT	Severe Thunderstorm Warning	DVN	Cedar, Clinton, Muscatine, Scott	30 min
May 17, 5:39 PM CDT	Severe Thunderstorm Warning	DVN	Henry, Jefferson, Keokuk, Van Buren, Washington	66 min
May 17, 5:50 PM CDT	Severe Thunderstorm Warning	DVN	Benton, Buchanan, Delaware, Iowa, Johnson, Linn and 1 more	55 min
May 17, 5:54 PM CDT	Severe Thunderstorm Warning	DVN	Jefferson, Van Buren	51 min
May 17, 6:01 PM CDT	Tornado Warning	DVN	Henry, Jefferson, Lee, Van Buren	59 min
May 17, 6:19 PM CDT	Tornado Warning	DVN	Johnson, Louisa, Washington	41 min
May 17, 6:28 PM CDT	Flash Flood Warning	DVN	Johnson, Linn	3 hr
May 17, 6:31 PM CDT	Severe Thunderstorm Warning	DVN	Buchanan, Cedar, Clinton, Delaware, Dubuque, Jackson and 5 more	59 min
May 17, 6:32 PM CDT	Tornado Warning Tornado observed	DVN	Delaware, Dubuque, Jones, Linn	43 min
May 17, 6:38 PM CDT	Severe Thunderstorm Warning	DVN	Henry, Louisa, Muscatine, Washington	52 min
May 17, 6:48 PM CDT	Tornado Warning	DVN	Cedar, Johnson, Muscatine	42 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.