Alert archive / Iowa / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 89, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jul 11, 1987, 3:43 PM CDT for Dickinson County, Emmet County, Iowa. It was in force for 32 min.
The area
The counties it named.
The facts
- Issued
- Jul 11, 1987, 3:43 PM CDT (20:43 UTC)
- Expired
- Jul 11, 1987, 4:15 PM CDT
- In force
- 32 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
Counties Dickinson County, IA, Emmet 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
Minneapolis, MN (KSTC), launched 12:00Z, 8.7 hours before the alert went out and 194 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
- 2637 J/kg
- Mixed-layer CIN
- -26 J/kg
- Mixed-layer LCL
- 638 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 25 m²/s²
- 0-3 km storm-relative helicity
- 43 m²/s²
- Significant tornado parameter
- 0.4
- Supercell composite
- 2.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KDSM 112044 SVRDSM IAC059-063-112115- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 343 PM CDT SAT JUL 11 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 415 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF NORTHWEST IOWA... EASTERN DICKINSON AND NORTHWEST EMMET AT 342 PM...WEATHER RADAR INDICATED A SEVERE THUNDERSTORM NEAR SPIRIT LAKE...ABOUT 20 MILES NORTH OF SPENCER. THE STORM WAS MOVING NORTHEAST AT 40 MILES AN HOUR. REMEMBER..A SEVERE THUNDERSTORM CAN PRODUCE DAMAGING WINDS IN EXCESS OF 60 MPH..LARGE HAIL..DEADLY LIGHTNING..AND HEAVY RAINS THAT CAN QUICKLY FLOOD LOW LYING AREAS. PEOPLE IN THE PATH OF THIS STORM SHOULD TAKE APPROPRIATE ACTION IMMEDIATELY. BARLOW/TRUETT
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, Jul 11, 9:44 AM CDT, 5 hours 59 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 943 AM CDT SAT JUL 11 1987 AT 935 AM...A LINE OF NUMEROUS SHOWERS AND SCATTERED STRONG THUNDERSTORMS STRETCHED FROM 30 MILES NORTHEAST OF SPENCER NEAR RINGSTED...IN SOUTHEAST EMMET COUNTY NORTHEAST INTO SOUTHERN MINNESOTA. THE STRONGEST STORM WAS LOCATED NEAR RINGSTED...AND IT COULD PRODUCE BRIEF VERY HEAVY RAIN...STRONG GUSTY WINDS AND SMALL HAIL. THE SHXOWERS AND STORMS WERE MOVING EAST NORTHEAST AT 35 MILES AN HOUR. BARLOW
Special weather statement, Jul 11, 1:12 PM CDT, 2 hours 31 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 110 PM CDT SAT JUL 11 1987 THE COMBINATION OF TEMPERATURE AND RELATIVE HUMIDITY HAS DRIVEN THE HEAT INDEX INTO THE HOT CATEGORY. THE HOT CATEGORY MEANS THAT HEAT EXHAUSTION...HEAT CRAMPS AND SUNSTROKE ARE POSSIBLE WITH PROLONGED EXPOSURE OR PHYSICAL EXERTION. PEOPLE PLANNING LENGTHY OUTDOOR ACTIVITIES THIS AFTERNOON SHOULD TAKE EXTRA PRECAUTIONS AND MONITOR PHYSICAL CONDITIONS. PEOPLE SHOULD WEAR LIGHT WEIGHT LOOSE FITTING CLOTHING AND HAVE PLENTY OF NON-ALCHOLIC BEVERAGES ON HAND. A RESPITE FROM THE EXTREME HEAT AND HUMIDITY IS EXPECTED OVER THE NEXT 24 HOURS AS A COLD FRONT WILL BE MOVING THROUGH THE STATE THIS ,EVENING BRINGING COOLER TEMPERATURES AND LOWER RELATIVE HUMIDITY. BARLOW
Special weather statement, Jul 11, 3:20 PM CDT, 23 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 314 PM CDT SAT JUL 11 1987 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR MOST OF WESTERN AND NORTHERN IOWA UNTIL 9PM THIS EVENING... AT 310 PM...A 20 MILE WIDE BAND OF SHOWERS AND ISOLATED INTENSE THUNDERSTORMS WAS LOCATED OVER THE FAR NORTHWEST COUNTIES OF IOWA. THE STRONGEST STORMS WERE LOCATED ABOUT 25 MILES NORTHWEST OF SPENCER IN EXTREME NORTHEAST OSCEOLA COUNTY...THE OTHER STORM WAS LOCATED 40 MILES NORTHWEST OF SPENCER IN THE EXTREME SOUTHEAST CORNER OF LYON COUNTY. ALTHOUGH THESE STORMS DO NOT APPEAR TO BE SEVERE AT THIS TIME...VERY HEAVY RAIN...STRONG GUSTY WINDS ALONG WITH SMALL HAIL AND DANGEROUS LIGHTNING CAN BE EXPECTED WITH THE PASSAGE OF THESE STORMS. PEOPLE ON OR AROUND AREA LAKES IN EXTREME NORTHWEST IOWA SHOULD BE PREPARED TO MOVE QUICKLY TO A PLACE OF SHELTER IF THESE STORMS APPROACH. MOVEMENT OF THE SHOWERS AND STORMS WAS EAST NORTHEAST AT 40 MILES AN HOUR. BARLOW/MILLER
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 11, 5:50 AM CDT | Severe Thunderstorm Warning | DMX | Kossuth | 40 min |
| Jul 11, 4:09 PM CDT | Severe Thunderstorm Warning | DMX | Dickinson | 31 min |
| Jul 11, 4:20 PM CDT | Severe Thunderstorm Warning | DMX | Emmet | 40 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.