Alert archive / Iowa / Severe Thunderstorm Watches in 2014

Severe Thunderstorm Watch 309

June 16, 201440 counties in Iowa; 15 counties in Nebraska

The Storm Prediction Center issued this severe thunderstorm watch at Jun 16, 2014, 9:56 PM CDT for 40 counties in Iowa; 15 counties in Nebraska. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jun 16, 2014, 9:56 PM CDT (02:56 UTC)
Expired
Jun 17, 2014, 3:16 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 55 counties

Adair County, IA, Appanoose County, IA, Audubon County, IA, Boone County, IA, Buena Vista County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cherokee County, IA, Clarke County, IA, Crawford County, IA, Dallas County, IA, Davis County, IA, Decatur County, IA, Greene County, IA, Guthrie County, IA, Hamilton County, IA, Harrison County, IA, Ida County, IA, Jasper County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Monona County, IA, Monroe County, IA, Plymouth County, IA, Pocahontas County, IA, Polk County, IA, Poweshiek County, IA, Sac County, IA, Shelby County, IA, Story County, IA, Tama County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA, Webster County, IA, Woodbury County, IA, Antelope County, NE, Boone County, NE, Burt County, NE, Colfax County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Madison County, NE, Pierce County, NE, Platte County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE, Wayne County, NE

The radar

The Omaha radar (KOAX), 114 km from the middle of the area, began a volume at 02:55 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
10%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jun 16, 10:15 PM CDTSevere Thunderstorm WarningFSDPlymouth, Woodbury45 min
Jun 16, 10:31 PM CDTSevere Thunderstorm WarningOAXThurston29 min
Jun 16, 10:34 PM CDTSevere Thunderstorm WarningFSDWoodbury26 min
Jun 16, 10:55 PM CDTSevere Thunderstorm WarningFSDIda, Woodbury50 min
Jun 16, 11:24 PM CDTSevere Thunderstorm WarningOAXMonona36 min
Jun 16, 11:32 PM CDTSevere Thunderstorm WarningFSDIda, Woodbury28 min
Jun 16, 11:34 PM CDTSevere Thunderstorm WarningDMXBoone, Story56 min
Jun 16, 11:40 PM CDTFlash Flood WarningDMXGrundy, Hamilton, Hardin, Webster, Wright6 hr
Jun 16, 11:42 PM CDTSevere Thunderstorm WarningDMXCalhoun, Carroll, Crawford, Sac63 min
Jun 17, 12:01 AM CDTSevere Thunderstorm WarningDMXAudubon, Boone, Dallas, Greene, Guthrie44 min
Jun 17, 12:38 AM CDTSevere Thunderstorm WarningDMXBoone, Dallas, Guthrie, Madison, Polk, Story and 1 more52 min
Jun 17, 12:40 AM CDTSevere Thunderstorm WarningFSDDixon50 min
Jun 17, 12:57 AM CDTSevere Thunderstorm WarningDMXBoone, Dallas, Polk33 min
Jun 17, 1:06 AM CDTFlash Flood WarningOAXCedar, Pierce4 hr
Jun 17, 1:21 AM CDTSevere Thunderstorm WarningDMXJasper, Marion, Polk, Warren39 min
Jun 17, 1:24 AM CDTSevere Thunderstorm WarningDMXClarke, Lucas, Madison, Warren51 min
Jun 17, 1:48 AM CDTSevere Thunderstorm WarningFSDDixon27 min
Jun 17, 1:57 AM CDTSevere Thunderstorm WarningDMXJasper, Lucas, Mahaska, Marion, Monroe, Poweshiek and 1 more63 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 00:00Z, 2.9 hours before the alert went out and 114 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 00:00Z on 2014-06-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3563 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 00:00Z on 2014-06-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 248 square meters per square second.19395878Sfc1 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
3563 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
1174 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
248 m²/s²
0-3 km storm-relative helicity
362 m²/s²
Significant tornado parameter
4.8
Supercell composite
28.3

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 16, 9:01 PM CDTSevere Thunderstorm WatchSPCBenton, Buchanan, Cedar, Clinton, Delaware, Des Moines and 13 more8 hr
Jun 16, 9:11 PM CDTMesoscale DiscussionSPCAudubon, Boone, Calhoun, Carroll, Cherokee, Crawford and 15 more64 min
Jun 16, 11:11 PM CDTMesoscale DiscussionSPCAdair, Audubon, Boone, Buena Vista, Calhoun, Carroll and 23 more64 min
Jun 16, 11:40 PM CDTMesoscale DiscussionSPCCedar, Clinton, Iowa, Jackson, Johnson, Jones and 5 more65 min
Jun 17, 1:29 AM CDTMesoscale DiscussionSPCAppanoose, Cedar, Clarke, Davis, Decatur, Des Moines and 23 more91 min
Jun 17, 3:41 AM CDTMesoscale DiscussionSPCClinton, Jackson, Scott64 min
Jun 17, 5:12 PM CDTMesoscale DiscussionSPCBuena Vista, Cherokee, Clay, Lyon, O'Brien, Osceola and 2 more2 hr
Jun 17, 6:48 PM CDTTornado WatchSPCBuena Vista, Cherokee, Clay, Dickinson, Ida, Lyon and 6 more6 hr
Jun 17, 3:22 PM CDTMesoscale DiscussionSPCBanner, Box Butte, Dawes, Garden, Kimball, Morrill and 3 more113 min
Jun 17, 4:53 PM CDTTornado WatchSPCBlaine, Brown, Cherry, Grant, Hooker, Keya Paha and 3 more6 hr

Nearby

Severe Thunderstorm Watches in Iowa, 2014Severe Thunderstorm Watches in Nebraska, 2014Every severe thunderstorm watch in 2014

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.