Alert archive / Iowa / Special Weather Statements in 2017
Special Weather Statement, NWS Des Moines, IA
NWS Des Moines, IA issued this special weather statement at Aug 19, 2017, 12:32 AM CDT for Boone County, Iowa. It was in force for 28 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
- Aug 19, 2017, 12:32 AM CDT (05:32 UTC)
- Expired
- Aug 19, 2017, 1:00 AM CDT
- In force
- 28 min
- Issued by
- NWS Des Moines, IA
County Boone County, IA
The radar
The Des Moines radar (KDMX), 35 km from the middle of the area, began a volume at 05:36 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 nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 5.5 hours before the alert went out and 204 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
- 1353 J/kg
- Mixed-layer CIN
- -118 J/kg
- Mixed-layer LCL
- 1673 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 30 m²/s²
- 0-3 km storm-relative helicity
- 61 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.1
The text
As transmitted.
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</html>What forecasters said that day
The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Des Moines, IA wrote its last area forecast discussion before this special weather statement went out at Aug 19, 12:09 AM CDT, 23 minutes earlier.
Area forecast discussion, Aug 19, 12:09 AM CDT, 23 minutes before
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</html>In the hours before
Special weather statement, Aug 18, 8:46 PM CDT, 3 hours 46 minutes before
Special Weather Statement National Weather Service Des Moines IA 846 PM CDT Fri Aug 18 2017 IAZ023-033-034-190400- Pocahontas-Sac-Calhoun- Including the cities of Pocahontas, Laurens, Rolfe, Fonda, Gilmore City, Sac City, Lake View, Odebolt, Wall Lake, Schaller, Early, Rockwell City, Manson, Lake City, and Pomeroy 846 PM CDT Fri Aug 18 2017 ...Strong thunderstorms approaching... At 8:45pm, National Weather Service Doppler Radar was tracking strong thunderstorms near Spirit Lake to west of Spencer. The storms west of Spencer have had a history of producing large hail and wind damage. The storms will reach northern Pocahontas and northern Sac Counties within the next 45 minutes to hour and fifteen minutes. This area remains under a Severe Thunderstorm Watch until 1 am Saturday. Please continue to monitor local media or NOAA Weather Radio for the latest weather information and for any warnings should they become necessary. Ansorge
Special weather statement, Aug 18, 8:50 PM CDT, 3 hours 42 minutes before
Special Weather Statement National Weather Service Des Moines IA 850 PM CDT Fri Aug 18 2017 IAZ004-005-015-190400- Emmet-Kossuth-Palo Alto- Including the cities of Estherville, Algona, and Emmetsburg 850 PM CDT Fri Aug 18 2017 ...Strong thunderstorms moving into northern Iowa... At 8:50pm, National Weather Service Doppler Radar was tracking strong thunderstorms from Fairmont, Minnesota to near Spirit Lake. These storms have had wind gusts up to 40 mph within the last hour. Wind gusts up to around 45 mph will be possible with these storms as they move to the southeast. This area remains under a Severe Thunderstorm Watch until 1 am Saturday. Please continue to monitor local media or NOAA Weather Radio for the latest weather information and for any warnings should they become necessary. Ansorge
Local storm report, Aug 18, 10:44 PM CDT, 1 hour 48 minutes before
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</html>Special weather statement, Aug 19, 12:32 AM CDT, 0 minutes before
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</html>The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 9:27 PM CDT | Severe Thunderstorm Warning | DMX | Palo Alto | 48 min |
| Aug 18, 9:49 PM CDT | Severe Thunderstorm Warning | DMX | Sac | 56 min |
| Aug 18, 10:03 PM CDT | Severe Thunderstorm Warning | DMX | Humboldt, Kossuth, Palo Alto, Pocahontas, Webster | 42 min |
| Aug 18, 10:27 PM CDT | Severe Thunderstorm Warning | DMX | Calhoun, Webster | 48 min |
| Aug 18, 11:09 PM CDT | Severe Thunderstorm Warning | DMX | Boone, Calhoun, Greene, Webster | 36 min |
Nearby
Special Weather Statements in Iowa, 2017Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.