Alert archive / Iowa / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 112, NWS Omaha, NE
NWS Omaha, NE issued this severe thunderstorm warning at Jul 30, 2021, 9:03 PM CDT for Fremont County, Mills County, Page County, Iowa. It was in force for 42 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 30, 2021, 9:03 PM CDT (02:03 UTC)
- Expired
- Jul 30, 2021, 9:45 PM CDT
- In force
- 42 min
- Issued by
- NWS Omaha, NE
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Fremont County, IA, Mills County, IA, Page County, IA
The radar
The Omaha radar (KOAX), 92 km from the middle of the area, began a volume at 02:04 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 30, 8:47 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 2.1 hours before the alert went out and 92 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
- 2669 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 967 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- 52 m²/s²
- 0-3 km storm-relative helicity
- 279 m²/s²
- Significant tornado parameter
- 3.4
- Supercell composite
- 19.5
The text
As transmitted.
258
WUUS53 KOAX 310203
SVROAX
IAC071-129-145-310245-
/O.NEW.KOAX.SV.W.0112.210731T0203Z-210731T0245Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Omaha/Valley Nebraska
903 PM CDT Fri Jul 30 2021
The National Weather Service in Omaha has issued a
* Severe Thunderstorm Warning for...
Northeastern Fremont County in southwestern Iowa...
Southeastern Mills County in southwestern Iowa...
Northwestern Page County in southwestern Iowa...
* Until 945 PM CDT.
* At 902 PM CDT, severe thunderstorms were located along a line
extending from 4 miles south of Emerson to 4 miles west of Malvern,
moving southeast at 25 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.
* Locations impacted include...
Essex and Shenandoah.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4074 9523 4076 9572 4105 9570 4103 9544
4095 9538 4091 9539 4090 9535
TIME...MOT...LOC 0202Z 317DEG 24KT 4096 9543 4101 9566
HAIL...1.00IN
WIND...60MPH
$$
Petersen2 follow-up statements
313
WWUS53 KOAX 310221
SVSOAX
Severe Weather Statement
National Weather Service Omaha/Valley Nebraska
921 PM CDT Fri Jul 30 2021
IAC071-129-145-310245-
/O.CON.KOAX.SV.W.0112.000000T0000Z-210731T0245Z/
Fremont IA-Mills IA-Page IA-
921 PM CDT Fri Jul 30 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM CDT
FOR NORTHEASTERN FREMONT...SOUTHEASTERN MILLS AND NORTHWESTERN PAGE
COUNTIES...
At 921 PM CDT, severe thunderstorms were located along a line
extending from near Essex to 6 miles south of Malvern, moving
southeast at 30 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage to
roofs, siding, and trees.
Locations impacted include...
Shenandoah, Essex, Tabor, Randolph, Imogene and Pierce Recreation
Area.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4074 9523 4076 9572 4098 9570 4095 9538
4091 9539 4090 9535
TIME...MOT...LOC 0221Z 317DEG 24KT 4087 9532 4092 9555
HAIL...1.00IN
WIND...60MPH
$$
Petersen440
WWUS53 KOAX 310242
SVSOAX
Severe Weather Statement
National Weather Service Omaha/Valley Nebraska
942 PM CDT Fri Jul 30 2021
IAC071-129-145-310251-
/O.EXP.KOAX.SV.W.0112.000000T0000Z-210731T0245Z/
Fremont IA-Mills IA-Page IA-
942 PM CDT Fri Jul 30 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN FREMONT...
SOUTHEASTERN MILLS AND NORTHWESTERN PAGE COUNTIES WILL EXPIRE AT 945
PM CDT...
The Severe Thunderstorm Warning has been replaced.
A Severe Thunderstorm Watch remains in effect until 200 AM CDT for
southwestern Iowa.
Remember, a Severe Thunderstorm Warning still remains in effect for
portions of Fremont and Page Counties.
LAT...LON 4074 9523 4076 9572 4098 9570 4095 9538
4091 9539 4090 9535
TIME...MOT...LOC 0241Z 317DEG 24KT 4079 9522 4084 9545
$$
PetersenThe office that day
Everything else NWS Omaha, NE issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 30, 8:06 PM CDT | Special Weather Statement | OAX | Pottawattamie | 24 min |
| Jul 30, 8:12 PM CDT | Severe Thunderstorm Warning | OAX | Pottawattamie, Shelby | 33 min |
| Jul 30, 8:42 PM CDT | Severe Thunderstorm Warning | OAX | Mills, Montgomery, Page, Pottawattamie | 33 min |
| Jul 30, 9:13 PM CDT | Severe Thunderstorm Warning | OAX | Montgomery, Page | 32 min |
| Jul 30, 9:39 PM CDT | Severe Thunderstorm Warning | OAX | Fremont, Page | 51 min |
| Jul 30, 10:12 PM CDT | Tornado Warning | OAX | Page | 18 min |
| Jul 31, 2:14 AM CDT | Special Weather Statement | OAX | Pottawattamie | 76 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 2021Every severe thunderstorm warning in 2021
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.