Alert archive / Iowa / Severe Thunderstorm Warnings in 2017
Severe Thunderstorm Warning 252, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jul 20, 2017, 7:58 PM CDT for Carroll County, Greene County, Iowa. It was in force for 21 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 20, 2017, 7:58 PM CDT (00:58 UTC)
- Expired
- Jul 20, 2017, 8:19 PM CDT
- In force
- 21 min
- Issued by
- NWS Des Moines, IA
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Carroll County, IA, Greene County, IA
The radar
The Des Moines radar (KDMX), 84 km from the middle of the area, began a volume at 00:59 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 20, 8:01 PM CDT | TSTM WND GST 60 | 3 Ne Willey, IA | SOME SMALL BRANCHES DOWN AS WELL. |
| Jul 20, 8:05 PM CDT | TSTM WND GST 56 | 3 W Glidden, IA | 49 KNOT/56 MPH WIND GUST AT CARROLL AIRPORT. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 1.0 hours before the alert went out and 159 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
- 2063 J/kg
- Mixed-layer CIN
- -81 J/kg
- Mixed-layer LCL
- 1736 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 5 m²/s²
- 0-3 km storm-relative helicity
- 65 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.5
The text
As transmitted.
834
WUUS53 KDMX 210058
SVRDMX
IAC027-073-210145-
/O.NEW.KDMX.SV.W.0252.170721T0058Z-170721T0145Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Des Moines IA
758 PM CDT THU JUL 20 2017
The National Weather Service in Des Moines has issued a
* Severe Thunderstorm Warning for...
Southwestern Greene County in west central Iowa...
Southeastern Carroll County in west central Iowa...
* Until 845 PM CDT.
* At 758 PM CDT, a severe thunderstorm was located near Glidden, or 8
miles southeast of Carroll, moving east at 25 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
* Locations impacted include...
Coon Rapids, Glidden, Scranton, Dedham, Willey, Ralston and Arthur
N Neu Airport.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4209 9482 4211 9448 4186 9452 4186 9455
4188 9487
TIME...MOT...LOC 0058Z 276DEG 20KT 4199 9474
HAIL...<.75IN
WIND...60MPH
$$
MF2 follow-up statements
274
WWUS53 KDMX 210108
SVSDMX
Severe Weather Statement
National Weather Service Des Moines IA
808 PM CDT THU JUL 20 2017
IAC027-073-210145-
/O.CON.KDMX.SV.W.0252.000000T0000Z-170721T0145Z/
Greene IA-Carroll IA-
808 PM CDT THU JUL 20 2017
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 PM CDT
FOR SOUTHWESTERN GREENE AND SOUTHEASTERN CARROLL COUNTIES...
At 806 PM CDT, a severe thunderstorm was located near Glidden, or 10
miles southeast of Carroll, moving east at 20 mph.
HAZARD...60 mph wind gusts.
SOURCE...Trained weather spotters. At 801 pm...an estimated 60 mph
wind gust was reported 3 miles northeast of Willey. In
addition...the Carroll Airport reported a wind gust of 56
mph.
IMPACT...Expect damage to roofs, siding, and trees.
Locations impacted include...
Coon Rapids, Glidden, Scranton, Dedham, Willey, Ralston and Arthur N
Neu Airport.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Prepare immediately for damaging winds. People outside should move
to a shelter, inside a strong building and away from windows.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4209 9482 4211 9448 4186 9452 4186 9455
4188 9487
TIME...MOT...LOC 0106Z 269DEG 18KT 4200 9469
HAIL...<.75IN
WIND...60MPH
$$
MF500
WWUS53 KDMX 210119
SVSDMX
Severe Weather Statement
National Weather Service Des Moines IA
819 PM CDT THU JUL 20 2017
IAC027-073-210128-
/O.CAN.KDMX.SV.W.0252.000000T0000Z-170721T0145Z/
Greene IA-Carroll IA-
819 PM CDT THU JUL 20 2017
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN GREENE AND
SOUTHEASTERN CARROLL COUNTIES IS CANCELLED...
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning has been cancelled. However gusty winds and
heavy rain are still possible with this thunderstorm.
LAT...LON 4209 9482 4211 9448 4186 9452 4186 9455
4188 9487
TIME...MOT...LOC 0116Z 276DEG 20KT 4199 9459
$$
MFThe office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 7:05 PM CDT | Special Weather Statement | DMX | Sac | 55 min |
| Jul 20, 7:12 PM CDT | Severe Thunderstorm Warning | DMX | Carroll, Crawford, Sac | 26 min |
| Jul 20, 7:13 PM CDT | Special Weather Statement | DMX | Guthrie | 47 min |
| Jul 20, 7:19 PM CDT | Severe Thunderstorm Warning | DMX | Greene, Guthrie | 41 min |
| Jul 20, 8:50 PM CDT | Special Weather Statement | DMX | Dallas | 55 min |
| Jul 20, 8:57 PM CDT | Severe Thunderstorm Warning | DMX | Boone, Dallas, Greene, Guthrie | 48 min |
| Jul 20, 9:19 PM CDT | Severe Thunderstorm Warning | DMX | Boone, Polk, Story | 56 min |
| Jul 20, 10:04 PM CDT | Severe Thunderstorm Warning | DMX | Grundy, Hardin, Jasper, Marshall, Story | 56 min |
| Jul 20, 10:37 PM CDT | Special Weather Statement | DMX | Marion | 38 min |
| Jul 20, 11:06 PM CDT | Special Weather Statement | DMX | Poweshiek | 39 min |
| Jul 20, 11:23 PM CDT | Special Weather Statement | DMX | Tama | 37 min |
| Jul 20, 11:29 PM CDT | Severe Thunderstorm Warning | DMX | Mahaska, Poweshiek | 31 min |
| Jul 21, 9:55 AM CDT | Flash Flood Watch | DMX | Black Hawk, Bremer, Butler, Grundy, Tama | 20 hr |
| Jul 21, 10:01 AM CDT | Flash Flood Warning | DMX | Bremer | 6 hr |
| Jul 21, 3:26 PM CDT | River Flood Watch | DMX | Black Hawk | 5 days |
Nearby
Severe Thunderstorm Warnings in Iowa, 2017Every severe thunderstorm warning 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.