Alert archive / Iowa / Severe Thunderstorm Warnings in 2016

Severe Thunderstorm Warning 80, NWS La Crosse, WI

September 19, 2016Clayton County, Iowa

NWS La Crosse, WI issued this severe thunderstorm warning at Sep 19, 2016, 2:56 PM CDT for Clayton County, Iowa. It was in force for 34 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: Sep 19, 2016, 2:56 PM CDT (19:56 UTC)
Expired: Sep 19, 2016, 3:30 PM CDT
In force: 34 min
Issued by: NWS La Crosse, WI
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Clayton County, IA

The radar

The La Crosse radar (KARX), 114 km from the middle of the area, began a volume at 19:55 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
Sep 19, 3:14 PM CDT	HAIL 1.75	4 Se Garnavillo, IA	.
Sep 19, 3:19 PM CDT	HAIL 1.75	2 N Guttenberg, IA	GRAPE TO GOLFBALL SIZED.

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
Sep 19, 2:31 PM CDT	Severe Thunderstorm Watch	SPC	3 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 7.9 hours before the alert went out and 139 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1974 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 117 m²/s²
0-3 km storm-relative helicity: 125 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

852 
WUUS53 KARX 191956
SVRARX
IAC043-192030-
/O.NEW.KARX.SV.W.0080.160919T1956Z-160919T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LA CROSSE WI
256 PM CDT MON SEP 19 2016

THE NATIONAL WEATHER SERVICE IN LA CROSSE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL CLAYTON COUNTY IN NORTHEASTERN IOWA...

* UNTIL 330 PM CDT

* AT 256 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED OVER
  GARNAVILLO...OR 8 MILES EAST OF ELKADER...MOVING SOUTHEAST AT 55
  MPH.

  HAZARD...60 MPH WIND GUSTS AND QUARTER SIZE HAIL. 

  SOURCE...RADAR INDICATED. 

  IMPACT...HAIL DAMAGE TO VEHICLES IS EXPECTED. EXPECT WIND DAMAGE 
           TO ROOFS...SIDING...AND TREES. 

* THIS SEVERE THUNDERSTORM WILL BE NEAR...()
  GUTTENBERG AROUND 305 PM CDT. 

THE MAIN THREAT FROM THIS STORM IS LARGE HAIL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 4265 9092 4285 9139 4306 9124 4297 9115
      4291 9114 4288 9110 4283 9110 4283 9108
      4276 9106 4275 9107 4269 9097 4268 9091
      4265 9090
TIME...MOT...LOC 1956Z 296DEG 49KT 4290 9124 

HAIL...1.00IN
WIND...60MPH
 
$$

SHEA

2 follow-up statements

077 
WWUS53 KARX 192017
SVSARX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
317 PM CDT MON SEP 19 2016

IAC043-192030-
/O.CON.KARX.SV.W.0080.000000T0000Z-160919T2030Z/
CLAYTON IA-
317 PM CDT MON SEP 19 2016

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM CDT
FOR CENTRAL CLAYTON COUNTY...

AT 317 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR CASSVILLE...OR
10 MILES SOUTHWEST OF LANCASTER...MOVING SOUTHEAST AT 55 MPH.

HAZARD...GOLF BALL SIZE HAIL AND 60 MPH WIND GUSTS. 

SOURCE...LAW ENFORCEMENT. REPORTED 4 MILES SOUTHEAST OF GARNAVILLO.

IMPACT...PEOPLE AND ANIMALS OUTDOORS WILL BE INJURED. EXPECT HAIL 
         DAMAGE TO ROOFS...SIDING...WINDOWS...AND VEHICLES. EXPECT 
         WIND DAMAGE TO ROOFS...SIDING...AND TREES. 

THIS SEVERE THUNDERSTORM WILL REMAIN OVER MAINLY RURAL AREAS OF
CENTRAL CLAYTON COUNTY...INCLUDING THE FOLLOWING LOCATIONS:
CLAYTON...J WOOD CAMPGROUND AND LOCK AND DAM 10.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 4283 9120 4297 9115 4291 9114 4288 9110
      4283 9110 4283 9108 4276 9106 4275 9107
TIME...MOT...LOC 2017Z 296DEG 49KT 4277 9089 

HAIL...1.75IN
WIND...60MPH
 
$$

SHEA

412 
WWUS53 KARX 192022
SVSARX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
322 PM CDT MON SEP 19 2016

IAC043-192031-
/O.EXP.KARX.SV.W.0080.000000T0000Z-160919T2030Z/
CLAYTON IA-
322 PM CDT MON SEP 19 2016

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL CLAYTON COUNTY WILL
EXPIRE AT 330 PM CDT...
        
THE STORM WHICH PROMPTED THE WARNING IS MOVING OUT OF THE WARNED
AREA. THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.

THIS STORM PRODUCED GOLF BALL SIZED HAIL IN THE GUTTENBERG IOWA
ACCORDING TO THE IOWA STATE PATROL.

LAT...LON 4283 9120 4297 9115 4291 9114 4288 9110
      4283 9110 4283 9108 4276 9106 4275 9107
TIME...MOT...LOC 2021Z 296DEG 49KT 4275 9083 

$$

SHEA

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 19, 2:24 PM CDT	Severe Thunderstorm Warning	ARX	Allamakee	21 min
Sep 19, 2:26 PM CDT	Special Weather Statement	ARX	Clayton	64 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2016 Every severe thunderstorm warning in 2016

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.