Alert archive / Iowa / Tornado Warnings in 2019

Tornado Warning 21, NWS Des Moines, IA

September 24, 2019Sac County, Iowa

NWS Des Moines, IA issued this tornado warning at Sep 24, 2019, 5:54 PM CDT for Sac County, Iowa. It was in force for 36 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: Sep 24, 2019, 5:54 PM CDT (22:54 UTC)
Expired: Sep 24, 2019, 6:30 PM CDT
In force: 36 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.5 in

County Sac County, IA

The radar

The Des Moines radar (KDMX), 154 km from the middle of the area, began a volume at 22:58 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
Sep 24, 4:43 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 10.9 hours before the alert went out and 156 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: 498 J/kg
Mixed-layer CIN: -185 J/kg
Mixed-layer LCL: 1159 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 241 m²/s²
0-3 km storm-relative helicity: 245 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

As transmitted.

812 
WFUS53 KDMX 242254
TORDMX
IAC161-242330-
/O.NEW.KDMX.TO.W.0021.190924T2254Z-190924T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Des Moines IA
554 PM CDT Tue Sep 24 2019

The National Weather Service in Des Moines  has issued a

* Tornado Warning for...
  Northwestern Sac County in west central Iowa...

* Until 630 PM CDT.
    
* At 553 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Galva, or 10 miles north of Ida Grove, moving east
  at 30 mph.

  HAZARD...Tornado and ping pong 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 tornadic thunderstorm will remain over mainly rural areas of
  northwestern Sac County, including the following locations...
  Nemaha, Early and Schaller.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This Tornado Warning replaces the Severe Thunderstorm Warning issued
for the same area.

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 4256 9539 4256 9509 4236 9506 4235 9532
      4247 9532 4247 9538 4248 9539
TIME...MOT...LOC 2253Z 258DEG 26KT 4248 9541 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

Beerends

3 follow-up statements

048 
WWUS53 KDMX 242306
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
606 PM CDT Tue Sep 24 2019

IAC161-242330-
/O.CON.KDMX.TO.W.0021.000000T0000Z-190924T2330Z/
Sac IA-
606 PM CDT Tue Sep 24 2019

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 630 PM CDT FOR
NORTHWESTERN SAC COUNTY...
    
At 606 PM CDT, a severe thunderstorm capable of producing a tornado
was located 8 miles east of Galva, or 10 miles south of Storm Lake,
moving east at 40 mph.

HAZARD...Tornado and quarter 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.

Locations impacted include...
Schaller, Early and Nemaha. 

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 4256 9535 4256 9509 4242 9507 4244 9532
      4247 9532 4247 9536 4249 9536
TIME...MOT...LOC 2306Z 260DEG 33KT 4249 9526 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Beerends

304 
WWUS53 KDMX 242320
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
620 PM CDT Tue Sep 24 2019

IAC161-242330-
/O.CON.KDMX.TO.W.0021.000000T0000Z-190924T2330Z/
Sac IA-
620 PM CDT Tue Sep 24 2019

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 630 PM CDT FOR NORTH
CENTRAL SAC COUNTY...
    
At 620 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Lakeside, or 7 miles south of Storm Lake, moving
northeast at 30 mph.

HAZARD...Tornado and quarter 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.

Locations impacted include...
Nemaha.

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 4256 9523 4256 9509 4248 9508 4248 9519
      4251 9524
TIME...MOT...LOC 2320Z 242DEG 25KT 4253 9517 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Beerends

716 
WWUS53 KDMX 242325
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
625 PM CDT Tue Sep 24 2019

IAC161-242334-
/O.EXP.KDMX.TO.W.0021.000000T0000Z-190924T2330Z/
Sac IA-
625 PM CDT Tue Sep 24 2019

...THE TORNADO WARNING FOR NORTH CENTRAL SAC COUNTY WILL EXPIRE AT
630 PM CDT...
    
The tornado threat has diminished and the Tornado Warning will be 
allowed to expire. 

A Tornado Watch remains in effect until midnight CDT for west central
Iowa.


LAT...LON 4256 9523 4256 9509 4248 9508 4248 9519
      4251 9524
TIME...MOT...LOC 2324Z 258DEG 26KT 4254 9513 

$$

Beerends

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 24, 5:36 PM CDT	Severe Thunderstorm Warning	DMX	Sac	54 min
Sep 24, 5:55 PM CDT	Severe Thunderstorm Warning	DMX	Emmet, Kossuth, Palo Alto	50 min
Sep 24, 6:29 PM CDT	Tornado Warning	DMX	Kossuth	31 min
Sep 24, 6:54 PM CDT	Severe Thunderstorm Warning	DMX	Kossuth, Winnebago	36 min

Nearby

Tornado Warnings in Iowa, 2019 Every tornado warning in 2019 Tornadoes in 2019

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.