Alert archive / Nebraska / Tornado Watches in 2015

Tornado Watch 265

June 6, 20154 states

The Storm Prediction Center issued this tornado watch at Jun 6, 2015, 8:45 PM CDT for 4 states. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Jun 6, 2015, 8:45 PM CDT (01:45 UTC)
Expired
Jun 7, 2015, 12:50 AM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
65 kt
All 47 counties

Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Ida County, IA, Lyon County, IA, Monona County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Cottonwood County, MN, Jackson County, MN, Lincoln County, MN, Lyon County, MN, Murray County, MN, Nobles County, MN, Pipestone County, MN, Rock County, MN, Antelope County, NE, Boone County, NE, Burt County, NE, Cedar County, NE, Colfax County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Garfield County, NE, Holt County, NE, Knox County, NE, Madison County, NE, Pierce County, NE, Platte County, NE, Stanton County, NE, Thurston County, NE, Wayne County, NE, Wheeler County, NE, Bon Homme County, SD, Clay County, SD, Lincoln County, SD, Minnehaha County, SD, Moody County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 91 km from the middle of the area, began a volume at 01:49 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
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
50%
One or more gusts of 65 knots or more
30%
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
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jun 6, 9:23 PM CDTFlash Flood WarningFSDPipestone3 hr
Jun 6, 10:11 PM CDTFlash Flood WarningFSDPlymouth, Woodbury3 hr
Jun 6, 10:32 PM CDTSevere Thunderstorm WarningFSDCherokee, Plymouth27 min
Jun 6, 10:51 PM CDTSevere Thunderstorm WarningOAXMonona24 min
Jun 6, 11:51 PM CDTSevere Thunderstorm WarningOAXHarrison, Monona, Shelby24 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, 1.8 hours before the alert went out and 173 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 2015-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1554 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 2015-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 184 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
1554 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
1214 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
184 m²/s²
0-3 km storm-relative helicity
388 m²/s²
Significant tornado parameter
0.9
Supercell composite
13.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

438 
WWUS20 KWNS 070142
SEL5  
SPC WW 070142
IAZ000-MNZ000-NEZ000-SDZ000-070800-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 265
NWS STORM PREDICTION CENTER NORMAN OK
845 PM CDT SAT JUN 6 2015

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  NORTHWESTERN IOWA
  SOUTHWESTERN MINNESOTA
  NORTHEASTERN NEBRASKA
  SOUTHEASTERN SOUTH DAKOTA

* EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 845 PM
  UNTIL 300 AM CDT.

* PRIMARY THREATS INCLUDE...
  A FEW TORNADOES POSSIBLE
  SCATTERED DAMAGING WINDS AND ISOLATED SIGNIFICANT GUSTS TO 75
    MPH POSSIBLE
  ISOLATED VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE

SUMMARY...GROWING CLUSTER OF SEVERE THUNDERSTORMS WILL SHIFT
GENERALLY EASTWARD ACROSS THE WATCH AREA THIS EVENING...WITH THE
POTENTIAL FOR A FEW EMBEDDED SUPERCELLS.  AS SUCH...THE FULL
SPECTRUM OF SEVERE WEATHER RISK -- HAIL...WIND AND TORNADO -- IS
PRESENT.  THE WIND-DAMAGE RISK WILL INCREASE EASTWARD ACROSS
NORTHERN IOWA AND SOUTHERN MINNESOTA WITH TIME.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 65 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES SOUTH SOUTHEAST OF
NORFOLK NEBRASKA TO 40 MILES EAST NORTHEAST OF BROOKINGS SOUTH
DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

&&

OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 262. WATCH NUMBER 262 WILL NOT BE IN EFFECT AFTER
845 PM CDT. CONTINUE...WW 263...WW 264...

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 27025.


...EDWARDS

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 6, 8:11 PM CDTMesoscale DiscussionSPCCherokee, Ida, Lyon, Monona, O'Brien, Osceola and 3 more64 min
Jun 6, 11:00 PM CDTMesoscale DiscussionSPCBuena Vista, Calhoun, Carroll, Cherokee, Clay, Crawford and 14 more2 hr
Jun 6, 11:23 PM CDTSevere Thunderstorm WatchSPCAdair, Audubon, Black Hawk, Boone, Bremer, Butler and 32 more6 hr
Jun 7, 1:56 AM CDTMesoscale DiscussionSPCAdair, Adams, Benton, Black Hawk, Bremer, Buchanan and 29 more2 hr
Jun 7, 1:52 PM CDTMesoscale DiscussionSPCAppanoose, Davis, Des Moines, Henry, Jefferson, Keokuk and 9 more53 min
Jun 7, 3:33 PM CDTSevere Thunderstorm WatchSPCAppanoose, Clarke, Davis, Decatur, Des Moines, Henry and 10 more4 hr
Jun 7, 6:21 PM CDTMesoscale DiscussionSPCDavis, Des Moines, Henry, Jefferson, Lee, Van Buren84 min
Jun 6, 7:44 PM CDTMesoscale DiscussionSPCBecker, Big Stone, Chippewa, Clay, Douglas, Grant and 11 more91 min
Jun 6, 10:24 PM CDTMesoscale DiscussionSPCChippewa, Kandiyohi, Lac qui Parle, Meeker, Morrison, Pope and 3 more66 min
Jun 6, 7:55 PM CDTMesoscale DiscussionSPCChase, Dundy, Frontier, Hayes, Hitchcock, Perkins and 1 more95 min
Jun 6, 10:33 PM CDTMesoscale DiscussionSPCChase, Dawson, Dundy, Frontier, Furnas, Gosper and 5 more57 min
Jun 7, 2:36 PM CDTMesoscale DiscussionSPCChase, Dundy, Hayes, Hitchcock, Perkins114 min
Jun 7, 5:31 PM CDTMesoscale DiscussionSPCRichardson89 min

Nearby

Tornado Watches in Nebraska, 2015Tornado Watches in Iowa, 2015Tornado Watches in Minnesota, 2015Every tornado watch in 2015

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.