Alert archive / Iowa / Tornado Warnings in 1999

Tornado Warning 21, NWS Des Moines, IA

April 8, 1999Davis County, Iowa

NWS Des Moines, IA issued this tornado warning at Apr 8, 1999, 6:05 PM CDT for Davis County, Iowa. It was in force for 35 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Apr 8, 1999, 6:05 PM CDT (23:05 UTC)
Expired: Apr 8, 1999, 6:40 PM CDT
In force: 35 min
Issued by: NWS Des Moines, IA
Area: Whole counties

County Davis County, IA

The radar

The Des Moines radar (KDMX), 155 km from the middle of the area, began a volume at 23:05 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
Apr 8, 6:15 PM CDT	Tornado F3	Bloomfield, 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
Apr 8, 5:15 PM CDT	Tornado Watch	SPC	4 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.1 hours before the alert went out and 187 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2467 m above ground
0-6 km bulk shear: 61 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 115 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.

999 
WFUS1 KDSM 082306 RRB
TORDSM
IAC051-082340-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
605 PM CDT THU APR 8 1999

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  DAVIS COUNTY IN SOUTHEASTERN IOWA

* UNTIL 640 PM CDT

* AT 604 PM CDT... LOCAL LAW ENFORCEMENT REPORTED A TORNADO 13 MILES
  SOUTH OF OTTUMWA OR 5 MILES SOUTHWEST OF FLORIS... MOVING NORTH
  NORTHEAST AT 40 MPH.

* THIS TORNADO CAN BE EXPECTED NEAR...
   FLORIS             BY 611 PM CDT

GO TO THE BASEMENT OR A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

JUNGBLUTH

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 8, 7:36 AM CDT	Severe Thunderstorm Warning	DMX	Adair	34 min
Apr 8, 7:47 AM CDT	Severe Thunderstorm Warning	DMX	Madison	33 min
Apr 8, 8:37 AM CDT	Severe Thunderstorm Warning	DMX	Warren	33 min
Apr 8, 11:43 AM CDT	Severe Thunderstorm Warning	DMX	Adair	32 min
Apr 8, 12:02 PM CDT	Severe Thunderstorm Warning	DMX	Boone	33 min
Apr 8, 12:05 PM CDT	Severe Thunderstorm Warning	DMX	Greene	35 min
Apr 8, 12:39 PM CDT	Severe Thunderstorm Warning	DMX	Dallas	36 min
Apr 8, 12:48 PM CDT	Severe Thunderstorm Warning	DMX	Marshall	47 min
Apr 8, 1:16 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Story	34 min
Apr 8, 1:48 PM CDT	Severe Thunderstorm Warning	DMX	Story	32 min
Apr 8, 2:45 PM CDT	Tornado Warning	DMX	Adams, Taylor	50 min
Apr 8, 2:57 PM CDT	Severe Thunderstorm Warning	DMX	Grundy, Hardin	33 min
Apr 8, 2:59 PM CDT	Tornado Warning	DMX	Cass	31 min
Apr 8, 3:18 PM CDT	Tornado Warning	DMX	Adair	42 min
Apr 8, 3:32 PM CDT	Severe Thunderstorm Warning	DMX	Audubon, Cass	48 min
Apr 8, 3:46 PM CDT	Tornado Warning	DMX	Guthrie	49 min
Apr 8, 3:52 PM CDT	Tornado Warning	DMX	Union	33 min
Apr 8, 3:55 PM CDT	Tornado Warning	DMX	Madison	35 min
Apr 8, 4:20 PM CDT	Tornado Warning	DMX	Dallas	50 min
Apr 8, 4:44 PM CDT	Tornado Warning	DMX	Wayne	36 min
Apr 8, 4:47 PM CDT	Tornado Warning	DMX	Polk	48 min
Apr 8, 4:56 PM CDT	Tornado Warning	DMX	Lucas, Warren	49 min
Apr 8, 5:07 PM CDT	Tornado Warning	DMX	Marion	48 min
Apr 8, 5:15 PM CDT	Tornado Warning	DMX	Dallas	35 min
Apr 8, 5:37 PM CDT	Tornado Warning	DMX	Marion, Monroe	33 min
Apr 8, 5:37 PM CDT	Tornado Warning	DMX	Jasper	33 min
Apr 8, 5:49 PM CDT	Tornado Warning	DMX	Appanoose	31 min
Apr 8, 5:51 PM CDT	Tornado Warning	DMX	Polk	49 min
Apr 8, 6:06 PM CDT	Tornado Warning	DMX	Mahaska	34 min
Apr 8, 6:16 PM CDT	Tornado Warning	DMX	Wapello	34 min

Nearby

Tornado Warnings in Iowa, 1999 Every tornado warning in 1999 Tornadoes in 1999

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.