Alert archive / Iowa / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 32, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Apr 27, 1991, 12:02 AM CDT for Mahaska County, Marion County, Monroe County, Iowa. It was in force for 28 min.
The area
The counties it named.
The facts
- Issued
- Apr 27, 1991, 12:02 AM CDT (05:02 UTC)
- Expired
- Apr 27, 1991, 12:30 AM CDT
- In force
- 28 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
Counties Mahaska County, IA, Marion County, IA, Monroe County, IA
The nearest sounding before it
Topeka, KS (KTOP), launched 00:00Z, 5.0 hours before the alert went out and 342 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
- NaN m above ground
- 0-6 km bulk shear
- 79 kt
- 0-1 km storm-relative helicity
- 409 m²/s²
- 0-3 km storm-relative helicity
- 485 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 17.2
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, Apr 26, 10:43 PM CDT, 1 hour 19 minutes before
IAZALL-270435- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 1040 PM CDT FRI APR 26 1991 ...A TORNADO WATCH REMAINS IN EFFECT FOR MUCH OF SOUTHWEST IOWA UNTIL 2 AM SATURDAY MORNING... ...A TORNADO WATCH REMAINS IN EFFECT UNTIL 1 AM FOR PORTIONS OF NORTH CENTRAL IOWA... ...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 4 AM SATURDAY FOR A LARGE PORTION OF SOUTHERN AND EASTERN IOWA... AT 1028 PM CDT...SHOWERS AND THUNDERSTORMS CONTINUED OVER MUCH OF THE WEST HALF OF IOWA. WITHIN THIS LARGE AREA OF SHOWERS AND STORMS...SCATTERED INTENSE STORMS CONTINUED OVER CENTRAL IOWA...AND WERE LOCATED IN A NARROW BAND...10 MILES WIDE...FROM NEAR STORY CITY...45 MILES NORTH OF DES MOINES...TO 15 MILES EAST OF DES MOINES. OVER SOUTHWEST IOWA...ANOTHER 10 MILE WIDE BAND...FROM NEAR ATLANTIC TO THE IOWA/MISSOURI BORDER SOUTH OF CLARINDA ...OR FROM 45 MILES EAST...TO 70 MILES SOUTHEAST OF COUNCIL BLUFFS. THESE INTENSE STORMS HAVE BEEN PRODUCING VERY LARGE AMOUNTS OF RAINFALL...FREQUENT DANGEROUS LIGHTNING...AND COULD PRODUCE HAIL AND BRIEF STRONG GUSTY WIND. THE SHOWERS AND STORMS WERE MOVING NORTHEAST AT 45 MILES AN HOUR. PEOPLE IN THE PATH OF THESE INTENSE THUNDERSTORMS SHOULD REMAIN ALERT FOR RAPIDLY CHANGING CONDITIONS...AND BE PREPARED TO SEEK SHELTER IMMEDIATELY SHOULD THREATENING WEATHER APPROACH. JAK/WPM
Special weather statement, Apr 26, 10:50 PM CDT, 1 hour 12 minutes before
IAZ006-007-270445- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 1050 PM CDT FRI APR 26 1991 AT 1045 PM...A VERY INTENSE THUNDERSTORM WAS NEAR IOWA FALLS WHICH IS 30 MILES WEST OF WATERLOO IN NORTH CENTRAL IOWA. THIS STORM IS LIKELY TO PRODUCE WINDS IN EXCESS OF 50 MILES AN HOUR AND SMALL HAIL WITH ITS PASSAGE. TH THE STORM WAS MOVING NORTH NORTHEAST AT 45 MILES AN HOUR. CITIES IN THE DIRECT PATH OF THIS STORM ARE IOWA &FALLS...ACKLEY AND POPEJOY. REMEMBER...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 400 AM. MCQUIRTER
Special weather statement, Apr 26, 11:14 PM CDT, 48 minutes before
IAZALL-270500- SPECIAL WEATHER STATEMENT AND IOWA WEATHER UPDATE NATIONAL WEATHER SERVICE DES MOINES IA 1115 PM CDT FRI APR 26 1991 ...A TORNADO WATCH REMAINS IN EFFECT FOR MUCH OF SOUTHWEST IOWA UNTIL 2 AM SATURDAY MORNING... ...A TORNADO WATCH REMAINS IN EFFECT UNTIL 1 AM FOR PORTIONS OF NORTH CENTRAL IOWA... ...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 4 AM SATURDAY FOR A LARGE PORTION OF SOUTHERN AND EASTERN IOWA... AT 11 PM CDT...SHOWERS AND THUNDERSTORMS CONTINUED OVER MUCH OF THE WEST TWO THIRDS OF IOWA...GENERALLY WEST OF A LINE FROM WATERLOO TO OTTUMWA. WITHIN THIS LARGE AREA OF SHOWERS AND STORMS...SCATTERED INTENSE STORMS CONTINUED OVER CENTRAL AND NORTH CENTRAL IOWA...IN A 10 MILE WIDE BAND EXTENDING FROM ACKLEY...35 MILES WEST OF WATERLOO...TO 25 MILES EAST OF DES MOINES NEAR MONROE. OTHER INTENSE STORMS WERE LOCATED FROM 50 MILES SOUTHWEST OF DES MOINES NEAR CRESTON TO 45 MILES NORTHWEST OF DES MOINES NEAR COON RAPIDS...AND FROM 20 MILES WEST TO 40 MILES NORTHEAST OF LAMONI. THESE INTENSE STORMS HAVE BEEN PRODUCING VERY LARGE AMOUNTS OF RAINFALL...FREQUENT DANGEROUS LIGHTNING...AND COULD PRODUCE HAIL AND BRIEF STRONG GUSTY WIND. THE SHOWERS AND STORMS WERE MOVING NORTHEAST AT 45 MILES AN HOUR. PEOPLE IN THE PATH OF THESE INTENSE THUNDERSTORMS SHOULD REMAIN ALERT FOR RAPIDLY CHANGING CONDITIONS...AND BE PREPARED TO SEEK SHELTER IMMEDIATELY SHOULD THREATENING WEATHER APPROACH.? WPM/JAK
Special weather statement, Apr 26, 11:14 PM CDT, 48 minutes before
IAZ002-003-006-007-270600- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR NORTHEAST IOWA NATIONAL WEATHER SERVICE WATERLOO IA 1110 PM CDT FRI APR 26 1991 ...A TORNADO WATCH IS IN EFFECT UNTIL 2AM FOR PARTS OF NORTH CENTRAL IOWA...A SEVERE THUNDERSTORM WATCH FOR PARTS OF NORTHEAST IOWA UNTIL 4AM CDT... AT 1110 PM CDT AN AREA OF VERY STRONG THUNDERSTORMS 15 MILES WIDE EXTENDED FROM 10 MILES EAST OF MASON CITY TO ABOUT 30 MILES SOUTHWEST WATERLOO SOUTH OF GRUNDY CENTER. THESE THUDERSTORMS WERE MOVING RAPIDLY TO THE NORTH AT ABOUT 45 MILES AN HOUR AND HAVE PRODUCED BRIEF HEAVY RAIN...WINDS TO AROUND 40 MILES AN HOUR AND FREQUENT LIGHTNING. THIS AREA OF THUNDERSTORMS WILL BE MOVING INTO ATHE PARKERSBURG... DUMONT...GRUNDY CENTER...ALLISON AND CLARKSVILLE AREAS BY MIDNIGHT THESE TOWNS ARE JUST WEST OF WATERLOO. THESE STORMS ARE POTENTIALLY DANGEROUS. TAKE COVER IMMEDIATELY IF SEVERE WEATHER OCCURS.
Special weather statement, Apr 26, 11:42 PM CDT, 20 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<body>
<main class="wrap">
<section class="card" role="status" aria-live="polite">
<div class="status" id="status">Temporary Notice</div>
<h1 id="headline">This service is currently unavailable.</h1>
<p id="message1">
The site you requested is temporarily down for maintenance or an unexpected outage.
</p>
<p id="message2">
Please try again in a few minutes.
</p>
<p class="small" id="detail">
If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>Special weather statement, Apr 26, 11:44 PM CDT, 18 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<body>
<main class="wrap">
<section class="card" role="status" aria-live="polite">
<div class="status" id="status">Temporary Notice</div>
<h1 id="headline">This service is currently unavailable.</h1>
<p id="message1">
The site you requested is temporarily down for maintenance or an unexpected outage.
</p>
<p id="message2">
Please try again in a few minutes.
</p>
<p class="small" id="detail">
If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 26, 7:43 PM CDT | Severe Thunderstorm Warning | DMX | Crawford | 32 min |
| Apr 26, 7:49 PM CDT | Tornado Warning | DMX | Crawford | 26 min |
| Apr 26, 8:19 PM CDT | Tornado Warning | DMX | Sac | 56 min |
| Apr 26, 8:36 PM CDT | Severe Thunderstorm Warning | DMX | Buena Vista | 29 min |
| Apr 26, 8:55 PM CDT | Severe Thunderstorm Warning | DMX | Ringgold | 30 min |
| Apr 26, 9:19 PM CDT | Severe Thunderstorm Warning | DMX | Decatur | 35 min |
| Apr 26, 9:19 PM CDT | Severe Thunderstorm Warning | DMX | Clarke | 41 min |
| Apr 26, 9:46 PM CDT | Severe Thunderstorm Warning | DMX | Polk, Warren | 44 min |
| Apr 26, 10:59 PM CDT | Severe Thunderstorm Warning | DMX | Lucas, Wayne | 31 min |
| Apr 26, 11:18 PM CDT | Tornado Warning | DMX | Wayne | 27 min |
| Apr 26, 11:23 PM CDT | Tornado Warning | DMX | Lucas | 37 min |
| Apr 27, 1:30 AM CDT | Severe Thunderstorm Warning | DMX | Mahaska | 45 min |
| Apr 27, 2:04 AM CDT | Tornado Warning | DMX | Iowa | 41 min |
| Apr 27, 2:04 AM CDT | Tornado Warning | DMX | Keokuk | 15 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 1991Every severe thunderstorm warning in 1991
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.