Alert archive / Iowa / Tornado Warnings in 2017

Tornado Warning 22, NWS La Crosse, WI

July 19, 2017Winneshiek County, Iowa

NWS La Crosse, WI issued this tornado warning at Jul 19, 2017, 5:44 PM CDT for Winneshiek County, Iowa. It was in force for 13 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: Jul 19, 2017, 5:44 PM CDT (22:44 UTC)
Expired: Jul 19, 2017, 5:57 PM CDT
In force: 13 min
Issued by: NWS La Crosse, WI
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.0 in

County Winneshiek County, IA

The radar

The La Crosse radar (KARX), 89 km from the middle of the area, began a volume at 22:46 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.

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 19, 3:29 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.7 hours before the alert went out and 196 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: 147 J/kg
Mixed-layer CIN: -138 J/kg
Mixed-layer LCL: 1286 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 56 m²/s²
0-3 km storm-relative helicity: 96 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted.

891 
WFUS53 KARX 192244
TORARX
IAC191-192315-
/O.NEW.KARX.TO.W.0022.170719T2244Z-170719T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service La Crosse WI
544 PM CDT WED JUL 19 2017

The National Weather Service in La Crosse has issued a

* Tornado Warning for...
  Southeastern Winneshiek County in northeastern Iowa...

* Until 615 PM CDT

* At 544 PM CDT, severe thunderstorms capable of producing both
  tornadoes and extensive straight line wind damage were located over
  Ossian, or 11 miles north of West Union, moving east at 70 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 tornadic thunderstorm will remain over mainly rural areas of
  southeastern Winneshiek County, including the following locations:
  Castalia, Festina and Frankville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
La Crosse.

This cluster of thunderstorms is capable of producing tornadoes and
widespread significant wind damage. Do not wait to see or hear the
tornado. For your protection move to an interior room on the lowest
floor of a building.

&&

LAT...LON 4308 9189 4317 9188 4320 9161 4318 9160
      4310 9160 4308 9161
TIME...MOT...LOC 2244Z 268DEG 62KT 4312 9178 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

RRS

2 follow-up statements

824 
WWUS53 KARX 192252 RRA
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
552 PM CDT WED JUL 19 2017

IAC191-192315-
/O.CON.KARX.TO.W.0022.000000T0000Z-170719T2315Z/
Winneshiek IA-
552 PM CDT WED JUL 19 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 615 PM CDT FOR
SOUTHEASTERN WINNESHIEK COUNTY...

At 551 PM CDT, a severe squall line capable of producing both
tornadoes and extensive straight line wind damage was located near
Postville, or 12 miles southwest of Waukon, moving east at 60 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 tornadic thunderstorm will remain over mainly rural areas of
southeastern Winneshiek County, including the following locations:
Castalia, Frankville and County Road W 46 And Centennial Road.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This cluster of thunderstorms is capable of producing tornadoes and
widespread significant wind damage. Do not wait to see or hear the
tornado. For your protection move to an interior room on the lowest
floor of a building.

&&

LAT...LON 4308 9174 4319 9174 4320 9161 4318 9160
      4310 9160 4308 9161
TIME...MOT...LOC 2251Z 265DEG 53KT 4313 9164 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

RRS

666 
WWUS53 KARX 192257
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
557 PM CDT WED JUL 19 2017

IAC191-192307-
/O.CAN.KARX.TO.W.0022.000000T0000Z-170719T2315Z/
Winneshiek IA-
557 PM CDT WED JUL 19 2017

...THE TORNADO WARNING FOR SOUTHEASTERN WINNESHIEK COUNTY IS
CANCELLED...
    
The tornado threat has diminished and the Tornado Warning has been 
cancelled. However, damaging winds remain likely and a Severe 
Thunderstorm Warning remains in effect for the area.

A severe thunderstorm watch remains in effect until 900 PM CDT for
northeastern Iowa.

LAT...LON 4308 9174 4319 9174 4320 9161 4318 9160
      4310 9160 4308 9161
TIME...MOT...LOC 2254Z 268DEG 62KT 4313 9150 

$$

RRS

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 19, 4:04 PM CDT	Special Weather Statement	ARX	Chickasaw, Floyd, Howard, Mitchell	86 min
Jul 19, 4:25 PM CDT	Severe Thunderstorm Warning	ARX	Floyd, Mitchell	65 min
Jul 19, 4:57 PM CDT	Severe Thunderstorm Warning	ARX	Chickasaw, Howard, Winneshiek	63 min
Jul 19, 5:04 PM CDT	Tornado Warning	ARX	Mitchell	10 min
Jul 19, 5:13 PM CDT	Tornado Warning	ARX	Howard	32 min
Jul 19, 5:19 PM CDT	Tornado Warning	ARX	Howard	10 min
Jul 19, 5:25 PM CDT	Severe Thunderstorm Warning	ARX	Allamakee, Clayton, Fayette, Winneshiek	80 min
Jul 19, 5:47 PM CDT	Tornado Warning	ARX	Fayette	11 min
Jul 19, 5:54 PM CDT	Tornado Warning	ARX	Clayton	24 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.