Alert archive / Iowa / Tornado Warnings in 2020

Tornado Warning 6, NWS Des Moines, IA

May 14, 20204 counties in Iowa

NWS Des Moines, IA issued this tornado warning at May 14, 2020, 4:46 PM CDT for 4 counties in Iowa. It was in force for 29 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 14, 2020, 4:46 PM CDT (21:46 UTC)
Expired: May 14, 2020, 5:15 PM CDT
In force: 29 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.75 in

Counties Clarke County, IA, Lucas County, IA, Marion County, IA, Warren County, IA

The radar

The Des Moines radar (KDMX), 62 km from the middle of the area, began a volume at 21:50 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
May 14, 5:00 PM CDT	HAIL 1	Milo, IA
May 14, 5:13 PM CDT	HAIL 1	8 E New Virginia, IA	REPORT FROM MPING: QUARTER (1.00 IN.).
May 14, 5:22 PM CDT	HAIL 0.88	7 E New Virginia, IA

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

Issued	Product	Office	Lasted
May 14, 4:24 PM CDT	Severe Thunderstorm Watch	SPC	9 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.8 hours before the alert went out and 243 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: 519 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 70 m²/s²
0-3 km storm-relative helicity: 59 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

875 
WFUS53 KDMX 142146
TORDMX
IAC039-117-125-181-142215-
/O.NEW.KDMX.TO.W.0006.200514T2146Z-200514T2215Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Des Moines IA
446 PM CDT Thu May 14 2020

The National Weather Service in Des Moines  has issued a

* Tornado Warning for...
  Northwestern Lucas County in south central Iowa...
  West central Marion County in south central Iowa...
  Northeastern Clarke County in south central Iowa...
  Southeastern Warren County in south central Iowa...

* Until 515 PM CDT.
    
* At 446 PM CDT, a severe thunderstorm capable of producing a tornado
  was located 13 miles south of Indianola, moving northeast at 35
  mph.

  HAZARD...Tornado and golf ball size hail.

  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...
  Melcher-Dallas around 510 PM CDT.

Other locations impacted by this tornadic thunderstorm include Otter
Creek County Park, Lacona, Milo and Sandyville.

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 4115 9365 4139 9337 4127 9319 4110 9347
TIME...MOT...LOC 2146Z 230DEG 32KT 4117 9352 

TORNADO...RADAR INDICATED
HAIL...1.75IN

$$

Kotenberg

2 follow-up statements

717 
WWUS53 KDMX 142206
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
506 PM CDT Thu May 14 2020

IAC039-142216-
/O.CAN.KDMX.TO.W.0006.000000T0000Z-200514T2215Z/
Clarke IA-
506 PM CDT Thu May 14 2020

...THE TORNADO WARNING FOR NORTHEASTERN CLARKE COUNTY IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until midnight CDT for
south central Iowa.

LAT...LON 4123 9351 4130 9337 4126 9320 4112 9343
TIME...MOT...LOC 2206Z 242DEG 21KT 4118 9340 

$$

IAC117-125-181-142215-
/O.CON.KDMX.TO.W.0006.000000T0000Z-200514T2215Z/
Lucas IA-Marion IA-Warren IA-
506 PM CDT Thu May 14 2020

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 515 PM CDT FOR NORTH
CENTRAL LUCAS...WEST CENTRAL MARION AND SOUTHEASTERN WARREN
COUNTIES...
    
At 506 PM CDT, a severe thunderstorm capable of producing a tornado
was located 8 miles west of Melcher-Dallas, or 12 miles north of
Chariton, moving northeast at 25 mph.

HAZARD...Tornado and half dollar size hail.

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...
  Melcher-Dallas around 530 PM CDT.

Other locations impacted by this tornadic thunderstorm include
Lacona.

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 4123 9351 4130 9337 4126 9320 4112 9343
TIME...MOT...LOC 2206Z 242DEG 21KT 4118 9340 

TORNADO...RADAR INDICATED
HAIL...1.25IN

$$

Kotenberg

851 
WWUS53 KDMX 142215
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
515 PM CDT Thu May 14 2020

IAC117-125-181-142225-
/O.EXP.KDMX.TO.W.0006.000000T0000Z-200514T2215Z/
Lucas IA-Marion IA-Warren IA-
515 PM CDT Thu May 14 2020

...THE TORNADO WARNING FOR NORTH CENTRAL LUCAS...WEST CENTRAL MARION
AND SOUTHEASTERN WARREN COUNTIES HAS EXPIRED...
    
The tornado threat has diminished and the Tornado Warning has been
cancelled. However, large hail and damaging winds remain likely and a
Severe Thunderstorm Warning remains in effect for the area.

A Severe Thunderstorm Watch remains in effect until midnight CDT for
south central Iowa.

LAT...LON 4123 9351 4130 9337 4126 9320 4112 9343
TIME...MOT...LOC 2215Z 230DEG 32KT 4123 9333 

$$

Kotenberg

The office that day

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

Issued	Product	Office	Counties	Lasted
May 14, 12:26 PM CDT	Flash Flood Watch	DMX	Davis, Wapello	11 hr
May 14, 2:36 PM CDT	Special Weather Statement	DMX	Guthrie	54 min
May 14, 3:35 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Dallas, Guthrie, Madison	40 min
May 14, 3:45 PM CDT	Special Weather Statement	DMX	Adair, Madison	45 min
May 14, 3:57 PM CDT	Special Weather Statement	DMX	Clarke, Madison, Marion, Warren	48 min
May 14, 4:08 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Madison, Warren	52 min
May 14, 4:14 PM CDT	Special Weather Statement	DMX	Dallas, Polk	61 min
May 14, 4:28 PM CDT	Special Weather Statement	DMX	Madison	32 min
May 14, 5:01 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Warren	29 min
May 14, 5:14 PM CDT	Severe Thunderstorm Warning	DMX	Lucas, Marion, Monroe, Warren	46 min
May 14, 5:29 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas, Marion, Warren	31 min
May 14, 5:44 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas, Union, Warren	31 min
May 14, 5:57 PM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Marion, Monroe	48 min
May 14, 6:13 PM CDT	Special Weather Statement	DMX	Decatur, Monroe, Wapello, Wayne	62 min
May 14, 6:20 PM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Monroe, Wapello	40 min
May 14, 6:56 PM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Monroe, Wapello	49 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.