Alert archive / Iowa / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 16, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at May 20, 1987, 3:30 PM CDT for Decatur County, Iowa. It was in force for 30 min.
The area
The counties it named.
The facts
- Issued
- May 20, 1987, 3:30 PM CDT (20:30 UTC)
- Expired
- May 20, 1987, 4:00 PM CDT
- In force
- 30 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Decatur County, IA
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
The nearest sounding before it
Omaha, NE (KOAX), launched 12:00Z, 8.5 hours before the alert went out and 226 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 3607 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 53 m²/s²
- 0-3 km storm-relative helicity
- 107 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
In the hours before
Special weather statement, May 20, 2:45 PM CDT, 45 minutes before
SPECIA KDSM 201945 SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 241 AM CDT WED MAY 20 1987 AT 235 AM...VERY STRONG THUNDERSTORMS WERE RAPIDLY DEVELOPING OVER THE SOUTHERN THIRD OF IOWAS COUNTIES. THE STRONGEST STORMS WERE LOCATED NEAR BEDFORD IN SOUTHWEST IOWA...ABOUT 70 MILES SOUTHWEST OF DES MOINES...ANOTHER STRONG STORM WAS LOCATED IN SOUTHEAST IOWA 5 MILES NORTHWEST OF BURLINGTON...STILL ANOTHER STRONG STORM WAS LOCATED 10 MILES EAST OF WAPELLO...OR 25 MILES NORTHWEST OF THE BURLINTON AREA. GUSTY SURFACE WINDS OF 35 TO 40 MILES AN HOUR... SMALL HAIL AND VERY HEAVY RAINS ALONG WITH DANGEROUS LIGHNING IS LIKELY WITH THESE STORMS. THESE STORMS WERE PART OFh A MUCH LARGER AREA SHOWERS AND STORMS THAT WERE RAPIDLY DEVELOPING OVER SOUTHERN IOWA AND NORTHERN MISSOURI. THE SHOWERS AND STORMS WERE MOVING NORTH AT 30 MILES AN HOUR. BARLOW
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 19, 8:05 PM CDT | Severe Thunderstorm Warning | DMX | Guthrie | 35 min |
| May 19, 8:24 PM CDT | Severe Thunderstorm Warning | DMX | Decatur | 66 min |
| May 19, 8:24 PM CDT | Severe Thunderstorm Warning | DMX | Ringgold | 46 min |
| May 20, 3:27 PM CDT | Severe Thunderstorm Warning | DMX | Union | 33 min |
| May 20, 4:37 PM CDT | Severe Thunderstorm Warning | DMX | Linn | 41 min |
| May 20, 5:49 PM CDT | Severe Thunderstorm Warning | DMX | Mahaska | 41 min |
| May 20, 6:05 PM CDT | Severe Thunderstorm Warning | DMX | Black Hawk | 20 min |
| May 20, 6:05 PM CDT | Severe Thunderstorm Warning | DMX | Bremer | 40 min |
| May 20, 6:20 PM CDT | Severe Thunderstorm Warning | DMX | Bremer | 60 min |
| May 20, 6:31 PM CDT | Severe Thunderstorm Warning | DMX | Tama | 19 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 1987Every severe thunderstorm warning in 1987
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.