Alert archive / Iowa / Tornado Warnings in 2018
Tornado Warning 2, NWS Omaha, NE
NWS Omaha, NE issued this tornado warning at Apr 13, 2018, 3:38 PM CDT for Mills County, Pottawattamie County, Iowa. It was in force for 22 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
- Apr 13, 2018, 3:38 PM CDT (20:38 UTC)
- Expired
- Apr 13, 2018, 4:00 PM CDT
- In force
- 22 min
- Issued by
- NWS Omaha, NE
- Area
- Storm-based polygon
- Tornado
- Radar indicated
- Hail
- 1.75 in
Counties Mills County, IA, Pottawattamie County, IA
The radar
The Omaha radar (KOAX), 87 km from the middle of the area, began a volume at 20:39 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 |
|---|---|---|---|
| Apr 13, 3:53 PM CDT | HAIL 1.5 | 1 Sse Oakland, IA | |
| Apr 13, 4:04 PM CDT | HAIL 1.75 | 2 S Oakland, IA |
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 |
|---|---|---|---|
| Apr 13, 2:19 PM CDT | Tornado Watch | SPC | 7 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 12:00Z, 8.6 hours before the alert went out and 88 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
- 230 J/kg
- Mixed-layer CIN
- -547 J/kg
- Mixed-layer LCL
- 838 m above ground
- 0-6 km bulk shear
- 59 kt
- 0-1 km storm-relative helicity
- 342 m²/s²
- 0-3 km storm-relative helicity
- 346 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.2
The text
As transmitted.
628
WFUS53 KOAX 132038
TOROAX
IAC129-155-132100-
/O.NEW.KOAX.TO.W.0002.180413T2038Z-180413T2100Z/
BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Omaha/Valley Nebraska
338 PM CDT FRI APR 13 2018
The National Weather Service in Omaha has issued a
* Tornado Warning for...
Northeastern Mills County in southwestern Iowa...
Southeastern Pottawattamie County in southwestern Iowa...
* Until 400 PM CDT
* At 338 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Macedonia, or 26 miles southwest of Atlantic,
moving northeast at 40 mph.
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...
Carson around 345 PM CDT.
Oakland around 355 PM CDT.
Other locations impacted by this tornadic thunderstorm include Old
Town Park, Farm Creek Public Wildlife Area and Henderson.
This includes Highway 59 in Iowa between mile markers 41 and 52, and
near mile marker 58.
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 4116 9535 4116 9538 4113 9539 4115 9550
4140 9534 4134 9515 4130 9516
TIME...MOT...LOC 2038Z 209DEG 36KT 4116 9543
TORNADO...RADAR INDICATED
HAIL...1.75IN
$$
BBARJENB2 follow-up statements
900
WWUS53 KOAX 132047
SVSOAX
Severe Weather Statement
National Weather Service Omaha/Valley Nebraska
347 PM CDT FRI APR 13 2018
IAC129-132055-
/O.CAN.KOAX.TO.W.0002.000000T0000Z-180413T2100Z/
Mills IA-
347 PM CDT FRI APR 13 2018
...THE TORNADO WARNING FOR NORTHEASTERN MILLS COUNTY IS CANCELLED...
The tornadic thunderstorm which prompted the warning has moved out
of the warned area. Therefore, the warning has been cancelled.
A tornado watch remains in effect until 900 PM CDT for southwestern
Iowa.
LAT...LON 4117 9536 4121 9546 4140 9534 4134 9515
4130 9516
TIME...MOT...LOC 2045Z 209DEG 36KT 4123 9538
$$
IAC155-132100-
/O.CON.KOAX.TO.W.0002.000000T0000Z-180413T2100Z/
Pottawattamie IA-
347 PM CDT FRI APR 13 2018
...A TORNADO WARNING REMAINS IN EFFECT UNTIL 400 PM CDT FOR
SOUTHEASTERN POTTAWATTAMIE COUNTY...
At 345 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Carson, or 22 miles southwest of Atlantic, moving
northeast at 40 mph.
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...
Carson at 345 PM CDT...
Oakland around 355 PM CDT.
Other locations impacted by this tornadic thunderstorm include Farm
Creek Public Wildlife Area.
This includes Highway 59 in Iowa between mile markers 44 and 52, and
near mile marker 58.
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 4117 9536 4121 9546 4140 9534 4134 9515
4130 9516
TIME...MOT...LOC 2045Z 209DEG 36KT 4123 9538
TORNADO...RADAR INDICATED
HAIL...1.75IN
$$
BB617
WWUS53 KOAX 132052
SVSOAX
Severe Weather Statement
National Weather Service Omaha/Valley Nebraska
352 PM CDT FRI APR 13 2018
IAC155-132102-
/O.EXP.KOAX.TO.W.0002.000000T0000Z-180413T2100Z/
Pottawattamie IA-
352 PM CDT FRI APR 13 2018
...THE TORNADO WARNING FOR SOUTHEASTERN POTTAWATTAMIE COUNTY WILL
EXPIRE AT 400 PM CDT...
The tornado threat has diminished and the Tornado Warning has been
cancelled. However, large hail and damaging winds remain likely and a
Severe Thunderstorm Warning remains in effect for the area.
A tornado watch remains in effect until 900 PM CDT for southwestern
Iowa.
LAT...LON 4117 9536 4121 9546 4140 9534 4134 9515
4130 9516
TIME...MOT...LOC 2052Z 209DEG 36KT 4129 9533
$$
BBThe office that day
Everything else NWS Omaha, NE issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 13, 3:01 PM CDT | Severe Thunderstorm Warning | OAX | Pottawattamie, Shelby | 29 min |
| Apr 13, 3:19 PM CDT | Winter Storm Warning | OAX | Monona | 23 hr |
| Apr 13, 3:19 PM CDT | Winter Weather Advisory | OAX | Harrison, Mills, Monona, Pottawattamie, Shelby | 33 hr |
| Apr 13, 3:22 PM CDT | Severe Thunderstorm Warning | OAX | Mills, Montgomery, Pottawattamie | 23 min |
| Apr 13, 3:27 PM CDT | Severe Thunderstorm Warning | OAX | Pottawattamie, Shelby | 33 min |
| Apr 13, 3:52 PM CDT | Severe Thunderstorm Warning | OAX | Pottawattamie, Shelby | 38 min |
| Apr 13, 4:06 PM CDT | Severe Thunderstorm Warning | OAX | Mills, Montgomery, Pottawattamie | 24 min |
| Apr 13, 4:24 PM CDT | Severe Thunderstorm Warning | OAX | Pottawattamie, Shelby | 36 min |
| Apr 13, 4:29 PM CDT | Severe Thunderstorm Warning | OAX | Fremont, Mills | 31 min |
| Apr 13, 4:34 PM CDT | Severe Thunderstorm Warning | OAX | Fremont | 26 min |
| Apr 13, 4:47 PM CDT | Severe Thunderstorm Warning | OAX | Mills, Montgomery, Pottawattamie | 43 min |
| Apr 13, 4:57 PM CDT | Severe Thunderstorm Warning | OAX | Fremont, Mills | 33 min |
| Apr 13, 6:36 PM CDT | Severe Thunderstorm Warning | OAX | Montgomery, Page | 24 min |
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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.