Alert archive / Iowa / Tornado Warnings in 2000

Tornado Warning 49, NWS Omaha, NE

July 26, 2000Pottawattamie County, Iowa

NWS Omaha, NE issued this tornado warning at Jul 26, 2000, 5:58 PM CDT for Pottawattamie County, Iowa. It was in force for 32 min. 7 reports came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued: Jul 26, 2000, 5:58 PM CDT (22:58 UTC)
Expired: Jul 26, 2000, 6:30 PM CDT
In force: 32 min
Issued by: NWS Omaha, NE
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Pottawattamie County, IA

The radar

The Omaha radar (KOAX), 99 km from the middle of the area, began a volume at 22:57 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Jul 26, 6:00 PM CDT	Tornado F0	Walnut, IA	A brief touchdown of a very narrow and short-lived tornado. The storm spotter that reported it said it appeared and then dissipated in a matter of 15 or 20 seconds, "it was very snake-like in appearance" according to the spotter.
Jul 26, 6:03 PM CDT	Hail 2.75	Atlantic, IA
Jul 26, 6:07 PM CDT	Hail 2.75	Atlantic, IA
Jul 26, 6:18 PM CDT	Hail 2.75	Atlantic, IA
Jul 26, 6:32 PM CDT	Hail 2.75	Oakland, IA
Jul 26, 6:32 PM CDT	Thunderstorm Wind 60 E	Oakland, IA	Thunderstorm winds downed trees and a machine shed east of Oakland.
Jul 26, 6:35 PM CDT	Thunderstorm Wind 61 E	Griswold, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 26, 2:30 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.0 hours before the alert went out and 100 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: 1188 J/kg
Mixed-layer CIN: -204 J/kg
Mixed-layer LCL: 918 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 28 m²/s²
0-3 km storm-relative helicity: 22 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.9

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KOAX 262258
TOROMA

IAC155-262330-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
558 PM CDT WED JUL 26 2000

THE NATIONAL WEATHER SERVICE IN OMAHA HAS ISSUED A

* TORNADO WARNING FOR...
  EASTERN POTTAWATTAMIE COUNTY IN SOUTHWEST IOWA

* UNTIL 630 PM CDT

* AT 552 PM CDT...RADAR INDICATED A THUNDERSTORM WITH VERY STRONG
  ROTATION AND A DEVELOPING TORNADO 2 MILES SOUTH OF WALNUT...OR
  ABOUT 44 MILES EAST OF OMAHA...MOVING SOUTH AT 10 MPH.

SOME LOCATIONS IN THE PATH OF THE TORNADO THROUGH 630 PM CDT   
INCLUDE...RURAL LOCATIONS IN EASTERN POTTAWATTAMIE COUNTY... 
ESPECIALLY ALONG COUNTY ROAD M47 BETWEEN INTERSTATE 80 AND HIGHWAY 
6.  

TAKE COVER NOW IN A BASEMENT OR IN AN INTERIOR ROOM ON THE LOWEST
LEVEL OF A STRONG BUILDING. CARS AND MOBILE HOMES SHOULD BE
ABANDONED. GO TO A SAFE PLACE NOW.

IN ADDITION TO THE TORNADO THREAT...THIS STORM HAS A HISTORY OF 
PRODUCING HAIL TO GOLFBALL SIZE.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 800 PM CDT WEDNESDAY EVENING
FOR SOUTHWESTERN IOWA AND EASTERN NEBRASKA.

LAT...LON 4153 9508 4154 9532 4125 9537 4124 9507

MEAD

The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 26, 5:06 PM CDT	Severe Thunderstorm Warning	OAX	Shelby	39 min
Jul 26, 5:26 PM CDT	Tornado Warning	OAX	Pottawattamie, Shelby	34 min
Jul 26, 6:28 PM CDT	Tornado Warning	OAX	Pottawattamie	47 min
Jul 26, 6:52 PM CDT	Severe Thunderstorm Warning	OAX	Montgomery	38 min

Nearby

Tornado Warnings in Iowa, 2000 Every tornado warning in 2000 Tornadoes in 2000

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.