Alert archive / Iowa / Tornado Watches in 2023

Tornado Watch 190

May 6, 202320 counties in Iowa; 19 counties in Missouri

The Storm Prediction Center issued this tornado watch at May 6, 2023, 3:56 PM CDT for 20 counties in Iowa; 19 counties in Missouri. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
May 6, 2023, 3:56 PM CDT (20:56 UTC)
Expired
May 6, 2023, 11:00 PM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
60 kt
All 39 counties

Adair County, IA, Adams County, IA, Appanoose County, IA, Clarke County, IA, Davis County, IA, Decatur County, IA, Fremont County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Monroe County, IA, Montgomery County, IA, Page County, IA, Ringgold County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA, Adair County, MO, Andrew County, MO, Atchison County, MO, Daviess County, MO, DeKalb County, MO, Gentry County, MO, Grundy County, MO, Harrison County, MO, Holt County, MO, Linn County, MO, Livingston County, MO, Macon County, MO, Mercer County, MO, Nodaway County, MO, Putnam County, MO, Randolph County, MO, Schuyler County, MO, Sullivan County, MO, Worth County, MO

The radar

The Des Moines radar (KDMX), 113 km from the middle of the area, began a volume at 20:57 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
40%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
40%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

22 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 6, 4:11 PM CDTSevere Thunderstorm WarningEAXAtchison34 min
May 6, 4:20 PM CDTSevere Thunderstorm WarningOAXFremont, Page40 min
May 6, 4:36 PM CDTSevere Thunderstorm WarningEAXAtchison, Holt, Nodaway39 min
May 6, 4:44 PM CDTSevere Thunderstorm WarningEAXAtchison, Nodaway46 min
May 6, 5:14 PM CDTSevere Thunderstorm WarningEAXGentry, Nodaway, Worth46 min
May 6, 5:22 PM CDTSevere Thunderstorm WarningEAXNodaway38 min
May 6, 5:34 PM CDTSevere Thunderstorm WarningEAXGentry, Nodaway26 min
May 6, 5:40 PM CDTTornado WarningEAXGentry, Nodaway20 min
May 6, 5:55 PM CDTTornado WarningEAXGentry, Harrison50 min
May 6, 6:33 PM CDTTornado WarningEAXDaviess, Grundy, Harrison, Mercer42 min
May 6, 7:00 PM CDTSevere Thunderstorm WarningEAXDaviess, Gentry, Harrison30 min
May 6, 7:14 PM CDTSevere Thunderstorm WarningEAXDaviess, Grundy, Harrison46 min
May 6, 7:20 PM CDTSevere Thunderstorm Warning Destructive damage threatEAXDaviess, Grundy, Harrison, Livingston40 min
May 6, 7:50 PM CDTTornado WarningEAXGrundy25 min
May 6, 7:53 PM CDTSevere Thunderstorm Warning Destructive damage threatEAXGrundy, Linn, Livingston, Sullivan52 min
May 6, 8:13 PM CDTTornado WarningEAXGrundy, Linn, Livingston32 min
May 6, 8:42 PM CDTSevere Thunderstorm Warning Considerable damage threatEAXChariton, Linn, Macon48 min
May 6, 8:44 PM CDTTornado Warning Tornado observedEAXLinn, Macon31 min
May 6, 9:12 PM CDTTornado WarningEAXChariton, Linn, Macon33 min
May 6, 9:19 PM CDTSevere Thunderstorm WarningEAXChariton, Macon, Randolph56 min
May 6, 9:48 PM CDTTornado WarningEAXMacon, Randolph27 min
May 6, 10:14 PM CDTSevere Thunderstorm Warning Considerable damage threatEAXMacon31 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 8.9 hours before the alert went out and 192 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-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 2023-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 2023-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 124 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
988 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
124 m²/s²
0-3 km storm-relative helicity
441 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 6, 1:42 AM CDTMesoscale DiscussionSPCCherokee, Crawford, Harrison, Ida, Monona, Sac and 1 more2 hr
May 6, 3:20 PM CDTMesoscale DiscussionSPCAdams, Appanoose, Clarke, Davis, Decatur, Fremont and 12 more2 hr
May 5, 7:45 PM CDTMesoscale DiscussionSPCDecatur, Jewell, Norton, Phillips, Smith2 hr
May 6, 6:25 PM CDTMesoscale DiscussionSPCAdair, Daviess, Gentry, Grundy, Harrison, Linn and 5 more95 min

Nearby

Tornado Watches in Iowa, 2023Tornado Watches in Missouri, 2023Every tornado watch in 2023

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.