Alert archive / Iowa / Tornado Warnings in 2020

Tornado Warning 4, NWS Des Moines, IA

March 28, 2020Black Hawk County, Iowa

NWS Des Moines, IA issued this tornado warning at Mar 28, 2020, 5:54 PM CDT for Black Hawk County, Iowa. It was in force for 17 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Mar 28, 2020, 5:54 PM CDT (22:54 UTC)
Expired: Mar 28, 2020, 6:11 PM CDT
In force: 17 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Black Hawk County, IA

The radar

The Des Moines radar (KDMX), 144 km from the middle of the area, began a volume at 22:56 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.

The watch it was issued in

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

Issued	Product	Office	Lasted
Mar 28, 2:45 PM CDT	Tornado Watch PDS	SPC	6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.9 hours before the alert went out and 176 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: 695 m above ground
0-6 km bulk shear: 72 kt
0-1 km storm-relative helicity: -128 m²/s²
0-3 km storm-relative helicity: 164 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

610 
WFUS53 KDMX 282254
TORDMX
IAC013-282330-
/O.NEW.KDMX.TO.W.0004.200328T2254Z-200328T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Des Moines IA
554 PM CDT Sat Mar 28 2020

The National Weather Service in Des Moines  has issued a

* Tornado Warning for...
  Central Black Hawk County in northeastern Iowa...

* Until 630 PM CDT.
    
* At 553 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Crossroads Mall, or near Waterloo, moving
  northeast at 45 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Elk Run Heights around 600 PM CDT.

Other locations impacted by this tornadic thunderstorm include
Dunkerton and Raymond.

This includes Interstate 380 between mile markers 69 and 73.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4238 9235 4241 9240 4263 9227 4257 9212
TIME...MOT...LOC 2253Z 212DEG 38KT 4243 9236 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

Ansorge

2 follow-up statements

645 
WWUS53 KDMX 282308
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
608 PM CDT Sat Mar 28 2020

IAC013-282330-
/O.CON.KDMX.TO.W.0004.000000T0000Z-200328T2330Z/
Black Hawk IA-
608 PM CDT Sat Mar 28 2020

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 630 PM CDT FOR
NORTHEASTERN BLACK HAWK COUNTY...
        
At 607 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Elk Run Heights, or 7 miles northeast of Waterloo,
moving northeast at 45 mph.

HAZARD...Tornado.

SOURCE...Weather spotters reported a rotating wall cloud east of 
         Crossroads Mall at 604 PM.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
northeastern Black Hawk County, including the following locations...
Dunkerton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4249 9222 4253 9231 4263 9227 4257 9212
TIME...MOT...LOC 2307Z 212DEG 38KT 4256 9225 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

Ansorge

486 
WWUS53 KDMX 282311 RRA
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
611 PM CDT Sat Mar 28 2020

IAC013-282321-
/O.CAN.KDMX.TO.W.0004.000000T0000Z-200328T2330Z/
Black Hawk IA-
611 PM CDT Sat Mar 28 2020

...THE TORNADO WARNING FOR NORTHEASTERN BLACK HAWK COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 900 PM CDT for northeastern
Iowa.

LAT...LON 4249 9222 4253 9231 4263 9227 4257 9212
TIME...MOT...LOC 2309Z 212DEG 38KT 4260 9222 

$$

Ansorge

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 28, 1:07 AM CDT	Severe Thunderstorm Warning	DMX	Monroe, Wapello	23 min
Mar 28, 2:18 AM CDT	Dense Fog Advisory	DMX	Adair, Adams, Appanoose, Boone, Clarke, Dallas and 21 more	7 min
Mar 28, 2:28 AM CDT	Dense Fog Advisory	DMX	Adair, Adams, Appanoose, Boone, Clarke, Dallas and 21 more	9 hr
Mar 28, 2:59 AM CDT	Wind Advisory	DMX	Adair, Adams, Appanoose, Audubon, Black Hawk, Boone and 45 more	34 hr
Mar 28, 4:56 AM CDT	Special Weather Statement	DMX	Mahaska	19 min
Mar 28, 9:55 AM CDT	River Flood Warning	DMX	Davis, Wapello	12 hr
Mar 28, 10:29 AM CDT	Special Weather Statement	DMX	Marion	46 min
Mar 28, 10:35 AM CDT	Special Weather Statement	DMX	Mahaska	40 min
Mar 28, 1:31 PM CDT	Special Weather Statement	DMX	Adams	44 min
Mar 28, 2:01 PM CDT	Special Weather Statement	DMX	Adair	44 min
Mar 28, 2:24 PM CDT	Tornado Warning Tornado observed	DMX	Adair, Guthrie, Madison	27 min
Mar 28, 3:49 PM CDT	Special Weather Statement	DMX	Hamilton, Wright	41 min
Mar 28, 3:51 PM CDT	Special Weather Statement	DMX	Hancock	39 min
Mar 28, 4:08 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo, Franklin, Hamilton, Hancock, Wright	31 min
Mar 28, 4:10 PM CDT	Tornado Warning	DMX	Jasper, Marshall, Story	35 min
Mar 28, 4:38 PM CDT	Special Weather Statement	DMX	Hancock, Winnebago	37 min
Mar 28, 4:38 PM CDT	Tornado Warning	DMX	Marshall	22 min
Mar 28, 5:22 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Pocahontas, Webster	38 min
Mar 28, 6:02 PM CDT	Tornado Warning	DMX	Black Hawk	9 min

Nearby

Tornado Warnings in Iowa, 2020 Every tornado warning in 2020 Tornadoes in 2020

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; radar from the NEXRAD Level II archive.