Alert archive / Iowa / Tornado Warnings in 2017

Tornado Warning 23, NWS La Crosse, WI

July 19, 2017Fayette County, Iowa

NWS La Crosse, WI issued this tornado warning at Jul 19, 2017, 5:47 PM CDT for Fayette County, Iowa. It was in force for 11 min. 2 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: Jul 19, 2017, 5:47 PM CDT (22:47 UTC)
Expired: Jul 19, 2017, 5:58 PM CDT
In force: 11 min
Issued by: NWS La Crosse, WI
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Fayette County, IA

The radar

The La Crosse radar (KARX), 102 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.

What was reported inside it

Time	Report	Where	Remark
Jul 19, 5:49 PM CDT	TSTM WND DMG	Clermont, IA	TREES DOWN
Jul 19, 5:49 PM CDT	TSTM WND DMG	Clermont, IA	TREES DOWN.

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

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.8 hours before the alert went out and 182 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.

165 
WFUS53 KARX 192247
TORARX
IAC065-192315-
/O.NEW.KARX.TO.W.0023.170719T2247Z-170719T2315Z/

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

The National Weather Service in La Crosse has issued a

* Tornado Warning for...
  Northeastern Fayette County in northeastern Iowa...

* Until 615 PM CDT

* At 546 PM CDT, severe thunderstorms capable of producing both
  tornadoes and extensive straight line wind damage were located near
  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. 

* These dangerous storms will be near...
  Clermont around 550 PM CDT. 
  Elgin around 555 PM CDT. 

Other locations impacted by this tornadic thunderstorm include
Eldorado, County Roads W 42 And B 40 and Montauk Historic Site.

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.

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 4295 9186 4308 9187 4308 9161 4298 9160
      4297 9161 4293 9161
TIME...MOT...LOC 2246Z 275DEG 60KT 4301 9175 

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

$$

RRS

1 follow-up statement

526 
WWUS53 KARX 192258
SVSARX

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

IAC065-192308-
/O.CAN.KARX.TO.W.0023.000000T0000Z-170719T2315Z/
Fayette IA-
558 PM CDT WED JUL 19 2017

...THE TORNADO WARNING FOR NORTHEASTERN FAYETTE 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 4295 9186 4308 9187 4308 9161 4298 9160
      4297 9161 4293 9161
TIME...MOT...LOC 2256Z 275DEG 60KT 4299 9148 

$$

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, 5:44 PM CDT	Tornado Warning	ARX	Winneshiek	13 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.