Alert archive / Iowa / Severe Thunderstorm Warnings in 1986

Severe Thunderstorm Warning 86, NWS Des Moines, IA

July 24, 1986Pocahontas County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 24, 1986, 7:19 PM CDT for Pocahontas County, Iowa. It was in force for 26 min.

The area

The counties it named.

The facts

Issued
Jul 24, 1986, 7:19 PM CDT (00:19 UTC)
Expired
Jul 24, 1986, 7:45 PM CDT
In force
26 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Pocahontas 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 00:00Z, 0.3 hours before the alert went out and 210 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.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 00:00Z on 1986-07-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 1986-07-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3586 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
92 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KDSM 250021
SVRDSM
IAC151-250100-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
719 PM CDT THU JUL 24 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM
WARNING EFFECTIVE UNTIL 745 PM CDT FOR PEOPLE IN THE FOLLOWING
COUNTY OF

NORTHWEST IOWA...NORTHEAST POCAHONTAS

AT 715 PM RADAR INDICTAED A SEVERE THUNDERSTORM NEAR POCAHONTAS
MOVING NORTHEAST AROUND 35 MILES AN HOUR.

THIS STORM WAS LOCATED 35 MILES NORTHWEST OF FORT DODGE.

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.

THESE STORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE
OR NO ADVANCE WARNING..SO BE ON THE LOOKOUT AND BE PREPARED TO MOVE
TO A PLACE OF SAFETY IF ONE IS SPOTTED.

BARLOW/CM/GF

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 24, 5:44 PM CDT, 1 hour 35 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
543 PM CDT THU JUL 24 1986

AT 535 PM CDT...STRONG THUNDERSTORMS WITH VERY HEAVY RAIN AND
POSSIBLY SMALL HAIL HAD RAPIDLY DEVELOPED OVER EXTREME NORTH
CENTRAL IOWA..ABOUT 15 MILES NORTH OF MASON CITY.

THESE STORMS WERE PART OF A MUCH LARGER AREA OF SHOWERS AND
STORMS THAT EXTENDED INTO SOUTHEAST MINNESOTA..AND NORTHEAST
NEBRASKA.

RAPID THUNDERSTORM ~DEVELOPEMENT IS LIKELY OVER MUCH OF NORTHWEST
IOWA BY 630 PM.

PEOPLE LIVNG IN NORTHWEST IOWA..SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER OVER THE NEXT TWO TO THREE HOURS.

THE STORMS WERE MOVING EAST AT 40 MILES AN HOUR.

BARLOW

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 24, 9:55 PM CDTSevere Thunderstorm WarningDMXDallas, Guthrie35 min
Jul 24, 10:33 PM CDTSevere Thunderstorm WarningDMXPolk27 min
Jul 24, 11:42 PM CDTSevere Thunderstorm WarningDMXIowa, Johnson, Linn33 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1986Every severe thunderstorm warning in 1986

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.