Tornado and High Wind in Iowa, April 23, 2001

Name: Tornado and High Wind in Iowa, April 23, 2001
Start: 2001-04-23T07:00
End: 2001-04-23T07:30
Location: Iowa

April 23, 2001 · NWS DMX · 3 events in 2 counties and zones

Where it happened

Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: $240,000
Crop damage: None recorded
Events: 3

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS DMX wrote it up.

An intense low pressure system lifted northeast out of the Rockies, across northwest Iowa and on into the upper Great Lakes during the afternoon of the 22nd into the 23rd. The dry slot lifted north ahead of the low and passed over Iowa during the early morning hours of the 23rd. Within the dry slot winds of 70 to 85 MPH were common just a few thousand feet above the surface. Shortly after sunrise, a narrow band of showers formed over northeast Iowa. As the showers moved through northeast they produced very gusty winds. In Black Hawk and Bremer Counties, winds were in the 65 to 70 MPH range. Damage was reported around the two counties. Three miles northwest of Washburn in Black Hawk County a farm shed was completely destroyed. In Bremer County, a farm shed was destroyed by the winds near Tripoli and damage to power poles was reported in the Readlyn area. At the onset of the high winds a very narrow squall line developed. Actually, forming near the cold core of the upper low pressure area, convective tops were very low with little if any lightning associated with them. A tornado touched down briefly in Black Hawk County near Gilbertville. One house was damaged and power was cut to three others. The tornado lifted quickly and didn't touch down again until it was east of the Des Moines CWA.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Des Moines, IA wrote its last area forecast discussion before the first event at Apr 23, 2:08 AM CST, 4 hours 52 minutes earlier.

Area forecast discussion, Apr 23, 2:08 AM CST, 4 hours 52 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
300 AM CDT MON 23 2001

SEVERAL CONCERNS THIS FORECAST PERIOD ARE TEMPERATURES WIND AND PCPN.

GENERAL TRENDS BY MODELS ARE THE SAME WITH THE USUAL DETAILED
DIFFERENCES IN TIMING AND SPEED AS SFC LO TRACKS NEWRD TDA INTO
UPPER GREAT LAKES REGION THO ETA REMAINS VEYR SLOW WITH THIS LO
LOCATIN IT JUST N OF KLSE BY 18Z WHILE ETA INVOF KIWD AT SAME TIME.
CURRENT SFC TRENDS OF FILLING LO WOULD FVR SLOER ETA TRACK.
MEANWHILE WRAPAROUND PCPN POSSIBLE AS CAA AND DAYTIME HEATING CREATE
MARGINAL INSTABILITY FOR LIGHT SHWRS BY AFTN.  DECENT CAA AND CLDS
SHOULD KEEP TEMPS FALLING.  SCTD LIGHT RAIN POSSIBLE DESPITE GOOD
DRY SLOT AS DEPICATED BY BY STLT.  LOOK AT Q/G FORCING MOST GD
FORCING IN MN TDA THO SOME WEAK FORCING HINTED BEHIND FNT.  ALL
MODELS CRANKING OUT PCPN.  AFT TDA ONE COLD NIGHT TONIGHT THEN WARM
UP BEGINS AND SUSTAINES ITSELF FOR THE ENT)IRE WEEK.

WILL NOT ISSUE ANY ADVSRY ATTM AFTER LOOKING AT WIND LAFT FCSTS AND
TREND OF SFC LO BUT GO WINDY TDA ESPECALLY N AND E.

.DSM...NONE

FORSTER

In the hours before

Special weather statement, Apr 23, 4:27 AM CST, 2 hours 33 minutes before

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
600 AM CDT MON APR 23 2001

THUNDERSTORMS ARE NOT EXPECTED ACROSS THE DES MOINES NATIONAL
WEATHER SERVICE FORECAST AREA TODAY OR TONIGHT.

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-241100-
ADAIR-ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE-BREMER-BUTLER-
CALHOUN-CARROLL-CASS-CERRO GORDO-CLARKE-CRAWFORD-DALLAS-DAVIS-
DECATUR-EMMET-FRANKLIN-GREENE-GRUNDY-GUTHRIE-HAMILTON-HANCOCK-HARDIN-
HUMBOLDT-JASPER-KOSSUTH-LUCAS-MADISON-MAHASKA-MARION-MARSHALL-MONROE-
PALO ALTO-POCAHONTAS-POLK-POWESHIEK-RINGGOLD-SAC-STORY-TAMA-TAYLOR-
UNION-WAPELLO-WARREN-WAYNE-WEBSTER-WINNEBAGO-WORTH-WRIGHT-
INCLUDING THE CITIES OF...ALGONA...AMES...ATLANTIC...BOONE...
CARROLL...CENTERVILLE...CHARITON...CRESTON...DENISON...
DES MOINES...ESTHERVILLE...FORT DODGE...GRINNELL...INDIANOLA...
IOWA FALLS...KNOXVILLE...LAMONI...MARSHALLTOWN...MASON CITY...
NEWTON...OSKALOOSA...OTTUMWA...PELLA...PERRY...WATERLOO...WAVERLY
AND WEBSTER CITY
600 AM CDT MON APR 23 2001

* EVENT TIMING... NO THUNDERSTORMS EXPECTED.

* THREAT CATEGORIES...
     TORNADO.......... NOT EXPECTED
     DAMAGING WINDS... NOT EXPECTED
     LARGE HAIL....... NOT EXPECTED
     FLASH FLOODING... NOT EXPECTED

* SPOTTER ACTIVATION OUTLOOK... NOT EXPECTED

-------------------------------------------------------------------

THREAT KEY:
    TORNADO.......... ANY TORNADO OCCURRENCE
    DAMAGING WINDS... WINDS >= 58 MPH
    LARGE HAIL....... HAIL >= 3/4 INCH DIAMETER
    FLASH FLOODING... FLOODING CAUSED BY HEAVY RAINS WITHIN 6 HOURS
                      OF RAIN EVENT. POSES THREAT TO LIFE OR
                      PROPERTY.

THREAT CATEGORY KEY:  PROBABILITY OF THREAT OCCURRING WITHIN 25
                      MILES OF POINT WITHIN FORECAST AREA
    NONE....... NOT EXPECTED.  LESS THAN 5% ( 2% FOR TORNADOES)
    LOW........ 5-15% (2-15% FOR TORNADOES)
    MODERATE... 25-35%
    HIGH....... 45% OR GREATER

SPOTTER ACTIVATION OUTLOOK KEY:
    NOT EXPECTED
    LOW........ ACTIVATION POSSIBLE BUT NOT LIKELY
    MODERATE... POSSIBILITIES ABOUT 50-50
    HIGH....... ACTIVATION LIKELY

FOR MORE INFORMATION ON PROBABILISTIC SEVERE WEATHER OUTLOOKS...GO
TO THE STORM PREDICTION CENTER WEBSITE AT
WWW.SPC.NOAA.GOV/PRODUCTS/OUTLOOK/PROBINFO.HTML .

Special weather statement, Apr 23, 5:00 AM CST, 2 hours before

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
600 AM CDT MON APR 23 2001

THUNDERSTORMS ARE NOT EXPECTED ACROSS THE DES MOINES NATIONAL
WEATHER SERVICE FORECAST AREA TODAY OR TONIGHT.

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-241100-
ADAIR-ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE-BREMER-BUTLER-
CALHOUN-CARROLL-CASS-CERRO GORDO-CLARKE-CRAWFORD-DALLAS-DAVIS-
DECATUR-EMMET-FRANKLIN-GREENE-GRUNDY-GUTHRIE-HAMILTON-HANCOCK-HARDIN-
HUMBOLDT-JASPER-KOSSUTH-LUCAS-MADISON-MAHASKA-MARION-MARSHALL-MONROE-
PALO ALTO-POCAHONTAS-POLK-POWESHIEK-RINGGOLD-SAC-STORY-TAMA-TAYLOR-
UNION-WAPELLO-WARREN-WAYNE-WEBSTER-WINNEBAGO-WORTH-WRIGHT-
INCLUDING THE CITIES OF...ALGONA...AMES...ATLANTIC...BOONE...
CARROLL...CENTERVILLE...CHARITON...CRESTON...DENISON...
DES MOINES...ESTHERVILLE...FORT DODGE...GRINNELL...INDIANOLA...
IOWA FALLS...KNOXVILLE...LAMONI...MARSHALLTOWN...MASON CITY...
NEWTON...OSKALOOSA...OTTUMWA...PELLA...PERRY...WATERLOO...WAVERLY
AND WEBSTER CITY
600 AM CDT MON APR 23 2001

* EVENT TIMING... NO THUNDERSTORMS EXPECTED.

* THREAT CATEGORIES...
     TORNADO.......... NOT EXPECTED
     DAMAGING WINDS... NOT EXPECTED
     LARGE HAIL....... NOT EXPECTED
     FLASH FLOODING... NOT EXPECTED

* SPOTTER ACTIVATION OUTLOOK... NOT EXPECTED

-------------------------------------------------------------------

THREAT KEY:
    TORNADO.......... ANY TORNADO OCCURRENCE
    DAMAGING WINDS... WINDS >= 58 MPH
    LARGE HAIL....... HAIL >= 3/4 INCH DIAMETER
    FLASH FLOODING... FLOODING CAUSED BY HEAVY RAINS WITHIN 6 HOURS
                      OF RAIN EVENT. POSES THREAT TO LIFE OR
                      PROPERTY.

THREAT CATEGORY KEY:  PROBABILITY OF THREAT OCCURRING WITHIN 25
                      MILES OF POINT WITHIN FORECAST AREA
    NONE....... NOT EXPECTED.  LESS THAN 5% ( 2% FOR TORNADOES)
    LOW........ 5-15% (2-15% FOR TORNADOES)
    MODERATE... 25-35%
    HIGH....... 45% OR GREATER

SPOTTER ACTIVATION OUTLOOK KEY:
    NOT EXPECTED
    LOW........ ACTIVATION POSSIBLE BUT NOT LIKELY
    MODERATE... POSSIBILITIES ABOUT 50-50
    HIGH....... ACTIVATION LIKELY

FOR MORE INFORMATION ON PROBABILISTIC SEVERE WEATHER OUTLOOKS...GO
TO THE STORM PREDICTION CENTER WEBSITE AT
WWW.SPC.NOAA.GOV/PRODUCTS/OUTLOOK/PROBINFO.HTML .

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

2 high wind, 1 tornado. Local standard time, as filed.

High Wind, Black Hawk

When: April 23, 7:00 AM CST to 7:30 AM CST
Where: Black Hawk forecast zone
Measured: 56 kt (64 mph)
Property damage: $100,000
Reported by: LAW ENFORCEMENT
Coordinates: 42.470, -92.309 (the zone’s center; the record gives no point)

High Wind, Bremer

When: April 23, 7:00 AM CST to 7:30 AM CST
Where: Bremer forecast zone
Measured: 61 kt (70 mph)
Property damage: $100,000
Reported by: LAW ENFORCEMENT
Coordinates: 42.775, -92.318 (the zone’s center; the record gives no point)

Tornado, Black Hawk

When: April 23, 7:15 AM CST
Where: Black Hawk County, 2 mi W of Gilbertville
Rating: F0
Path length: 0.3 mi
Path width: 30 yd
Property damage: $40,000
Reported by: NEWSPAPER
Coordinates: 42.417, -92.250

Brief touchdown with minor damage to buildings.

What these are

High Wind: Sustained non-thunderstorm winds of 40 mph or more for an hour, or gusts of 58 mph or more.
Tornado: A violently rotating column of air in contact with the ground and extending from a thunderstorm, filed with its path, width and Fujita or Enhanced Fujita rating from the damage survey.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Iowa in 2001 Every state in 2001 This day in weather history The tornado archive for Iowa, 2001 Warnings in Iowa, April 2001

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5237589, 5237590, 5237591.