Alert archive / Iowa / Tornado Warnings in 2018
Tornado Warning 55, NWS Des Moines, IA
NWS Des Moines, IA issued this tornado warning at Sep 4, 2018, 4:45 PM CDT for Hancock County, Winnebago County, Iowa. It was in force for 30 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
- Sep 4, 2018, 4:45 PM CDT (21:45 UTC)
- Expired
- Sep 4, 2018, 5:15 PM CDT
- In force
- 30 min
- Issued by
- NWS Des Moines, IA
- Area
- Storm-based polygon
- Tornado
- Radar indicated
- Hail
- 0.75 in
Counties Hancock County, IA, Winnebago County, IA
The radar
The Des Moines radar (KDMX), 170 km from the middle of the area, began a volume at 21:49 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 |
|---|---|---|---|
| Sep 4, 3:35 PM CDT | Tornado Watch | SPC | 7 hr |
The nearest sounding before it
Minneapolis, MN (KMPX), launched 12:00Z, 9.8 hours before the alert went out and 178 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.
- Mixed-layer CAPE
- 106 J/kg
- Mixed-layer CIN
- -31 J/kg
- Mixed-layer LCL
- 667 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 45 m²/s²
- 0-3 km storm-relative helicity
- 71 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
044
WFUS53 KDMX 042145
TORDMX
IAC081-189-042215-
/O.NEW.KDMX.TO.W.0055.180904T2145Z-180904T2215Z/
BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Des Moines IA
445 PM CDT TUE SEP 4 2018
The National Weather Service in Des Moines has issued a
* Tornado Warning for...
Northwestern Hancock County in north central Iowa...
Southwestern Winnebago County in north central Iowa...
* Until 515 PM CDT.
* At 445 PM CDT, a severe thunderstorm capable of producing a tornado
was located 10 miles northwest of Britt, or 13 miles west of Forest
City, moving northeast at 30 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
northwestern Hancock and southwestern Winnebago Counties, including
the following locations... Crystal Lake, Woden and Thompson.
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 4316 9389 4324 9397 4341 9381 4330 9362
TIME...MOT...LOC 2145Z 228DEG 24KT 4323 9390
TORNADO...RADAR INDICATED
HAIL...<.75IN
$$
Cogil3 follow-up statements
111
WWUS53 KDMX 042157
SVSDMX
Severe Weather Statement
National Weather Service Des Moines IA
457 PM CDT TUE SEP 4 2018
IAC081-042206-
/O.CAN.KDMX.TO.W.0055.000000T0000Z-180904T2215Z/
Hancock IA-
457 PM CDT TUE SEP 4 2018
...THE TORNADO WARNING FOR NORTHWESTERN HANCOCK COUNTY IS
CANCELLED...
The tornadic thunderstorm which prompted the warning has moved out
of the warned area. Therefore, the warning has been cancelled.
A Tornado Watch remains in effect until 1000 PM CDT for north central
Iowa.
LAT...LON 4333 9367 4326 9377 4325 9381 4326 9390
4341 9381
TIME...MOT...LOC 2156Z 221DEG 26KT 4329 9382
$$
IAC189-042215-
/O.CON.KDMX.TO.W.0055.000000T0000Z-180904T2215Z/
Winnebago IA-
457 PM CDT TUE SEP 4 2018
...A TORNADO WARNING REMAINS IN EFFECT UNTIL 515 PM CDT FOR
SOUTHWESTERN WINNEBAGO COUNTY...
At 456 PM CDT, a severe thunderstorm capable of producing a tornado
was located 9 miles west of Forest City, moving northeast at 30 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.
Locations impacted include...
Thompson.
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 4333 9367 4326 9377 4325 9381 4326 9390
4341 9381
TIME...MOT...LOC 2156Z 221DEG 26KT 4329 9382
TORNADO...RADAR INDICATED
HAIL...<.75IN
$$
Cogil285
WWUS53 KDMX 042204
SVSDMX
Severe Weather Statement
National Weather Service Des Moines IA
504 PM CDT TUE SEP 4 2018
IAC189-042215-
/O.CON.KDMX.TO.W.0055.000000T0000Z-180904T2215Z/
Winnebago IA-
504 PM CDT TUE SEP 4 2018
...A TORNADO WARNING REMAINS IN EFFECT UNTIL 515 PM CDT FOR SOUTH
CENTRAL WINNEBAGO COUNTY...
At 504 PM CDT, a severe thunderstorm capable of producing a tornado
was located 8 miles northwest of Forest City, moving northeast at 30
mph.
HAZARD...Tornado.
SOURCE...Radar indicated rotation.
IMPACT...Flying debris will be dangerous to those caught without
shelter. Mobile homes will be damaged or destroyed. Damage
to roofs, windows, and vehicles will occur. Tree damage is
likely.
Locations impacted include...
Thompson.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.
&&
LAT...LON 4333 9367 4328 9376 4334 9384 4341 9381
TIME...MOT...LOC 2204Z 222DEG 26KT 4334 9377
TORNADO...RADAR INDICATED
HAIL...<.75IN
$$
Cogil370
WWUS53 KDMX 042213
SVSDMX
Severe Weather Statement
National Weather Service Des Moines IA
513 PM CDT TUE SEP 4 2018
IAC189-042223-
/O.EXP.KDMX.TO.W.0055.000000T0000Z-180904T2215Z/
Winnebago IA-
513 PM CDT TUE SEP 4 2018
...THE TORNADO WARNING FOR SOUTH CENTRAL WINNEBAGO COUNTY WILL EXPIRE
AT 515 PM CDT...
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.
A Tornado Watch remains in effect until 1000 PM CDT for north central
Iowa.
To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Des Moines .
LAT...LON 4333 9367 4328 9376 4334 9384 4341 9381
TIME...MOT...LOC 2213Z 228DEG 24KT 4337 9372
$$
CogilThe office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 3, 7:32 PM CDT | Special Weather Statement | DMX | Black Hawk, Bremer, Grundy | 88 min |
| Sep 3, 7:43 PM CDT | Flash Flood Warning | DMX | Black Hawk | 3 hr |
| Sep 4, 3:33 AM CDT | Flash Flood Watch | DMX | Black Hawk, Boone, Bremer, Butler, Calhoun, Cerro Gordo and 22 more | 27 hr |
| Sep 4, 9:34 AM CDT | River Flood Watch | DMX | Cerro Gordo, Floyd, Worth | 13 hr |
| Sep 4, 9:34 AM CDT | River Flood Watch | DMX | Black Hawk, Bremer, Butler | 25 hr |
| Sep 4, 2:21 PM CDT | Severe Thunderstorm Warning | DMX | Palo Alto, Pocahontas | 14 min |
| Sep 4, 3:46 PM CDT | Tornado Warning | DMX | Kossuth | 29 min |
| Sep 4, 5:09 PM CDT | Flash Flood Warning | DMX | Hancock, Kossuth, Winnebago | 6 hr |
Nearby
Tornado Warnings in Iowa, 2018Every tornado warning in 2018Tornadoes in 2018
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.