Alert archive / Iowa / Severe Thunderstorm Warnings in 1993

Severe Thunderstorm Warning 172, NWS Des Moines, IA

July 27, 1993Tama County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 27, 1993, 7:14 PM CDT for Tama County, Iowa. It was in force for 31 min.

The area

The counties it named.

The facts

Issued: Jul 27, 1993, 7:14 PM CDT (00:14 UTC)
Expired: Jul 27, 1993, 7:45 PM CDT
In force: 31 min
Issued by: NWS Des Moines, IA
Area: Whole counties

County Tama County, IA

The nearest sounding before it

Minneapolis, MN (KSTC), launched 00:00Z, 0.2 hours before the alert went out and 320 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 175 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 1555 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 20 m²/s²
0-3 km storm-relative helicity: 35 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

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, Jul 27, 4:44 PM CDT, 2 hours 30 minutes before

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Special weather statement, Jul 27, 5:06 PM CDT, 2 hours 8 minutes before

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Special weather statement, Jul 27, 5:49 PM CDT, 1 hour 25 minutes before

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Special weather statement, Jul 27, 5:59 PM CDT, 1 hour 15 minutes before

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Special weather statement, Jul 27, 6:40 PM CDT, 34 minutes before

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Special weather statement, Jul 27, 6:47 PM CDT, 27 minutes before

IAZALL-280040-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
642 PM CDT TUE JUL 27 1993

...A TORNADO WATCH IS IN EFFECT FOR THE EASTERN TWO THIRDS OF IOWA
   UNTIL 10PM...

AT 633 PM CDT...VERY STRONG THUNDERSTORMS PERSISTED OVER CENTRAL IOWA.
THESE STORMS WERE CLUSTERED BETWEEN OGDEN...STORY CITY AND 10 MILES
EAST OF NEVADA...OR WITHIN A 25 MILE RADIUS OF AMES. THE STORMS IN
THIS AREA WILL PRODUCE VERY HEAVY RAIN...FREQUENT DEADLY LIGHTNING
AND SOME PEA TO MARBLE SIZED HAIL.

THESE STORMS WERE PART OF A 25 TO 45 MILE WIDE AREA OF SHOWERS AND
STORMS THAT EXTENDED FROM 45 MILES WEST OF DES MOINES NEAR ADAIR
NORTHEAST TO INDEPENDENCE. INDEPENDENCE IS 20 MILES EAST OF WATERLOO.

ISOLATED THUNDERSTORMS WERE LOCATED 10 MILES SOUTHWEST OF MASON CITY
AND BETWEEN CHARLES CITY AND CRESCO. CHARLES CITY IS 30 MILES EAST
OF WATERRLOO WHILE CRESCO IS 55 MILES NORTHEAST OF MASON CITY.

THE SHOWERS AND STORMS MOVING EAST NORTHEAST AT 30 MILES AN HOUR.

BARLOW/PRENTICE

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 27, 7:10 PM CDT	Severe Thunderstorm Warning	DMX	Grundy	17 min
Jul 27, 7:14 PM CDT	Severe Thunderstorm Warning	DMX	Marshall	21 min
Jul 27, 7:44 PM CDT	Severe Thunderstorm Warning	DMX	Benton	31 min
Jul 27, 8:08 PM CDT	Severe Thunderstorm Warning	DMX	Linn	37 min
Jul 27, 8:10 PM CDT	Severe Thunderstorm Warning	DMX	Buchanan	35 min
Jul 27, 9:18 PM CDT	Severe Thunderstorm Warning	DMX	Benton, Iowa	27 min
Jul 27, 9:44 PM CDT	Severe Thunderstorm Warning	DMX	Linn	46 min
Jul 27, 9:50 PM CDT	Flash Flood Warning	DMX	Benton	3 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 1993 Every severe thunderstorm warning in 1993

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.