Alert archive / Nebraska / Tornado Watches in 2011

Tornado Watch 563

June 26, 201110 counties in Nebraska

The Storm Prediction Center issued this tornado watch at Jun 26, 2011, 8:02 PM CDT for 10 counties in Nebraska. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Jun 26, 2011, 8:02 PM CDT (01:02 UTC)
Expired: Jun 26, 2011, 10:50 PM CDT
In force: 3 hr
Issued by: the Storm Prediction Center
Largest hail expected: 3 in
Strongest gust expected: 70 kt

Counties Cass County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE, Saline County, NE

The radar

The Omaha radar (KOAX), 112 km from the middle of the area, began a volume at 01:04 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: 30%
Ten or more severe wind reports: 30%
One or more gusts of 65 knots or more: 30%
Ten or more severe hail reports: 40%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 70%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Jun 26, 8:06 PM CDT	Severe Thunderstorm Warning	OAX	Cass, Dodge, Douglas, Lancaster, Sarpy, Saunders and 1 more	39 min
Jun 26, 8:15 PM CDT	Severe Thunderstorm Warning	OAX	Gage, Lancaster, Saline, Seward	34 min
Jun 26, 8:22 PM CDT	Severe Thunderstorm Warning	OAX	Cass, Sarpy	38 min
Jun 26, 8:33 PM CDT	Severe Thunderstorm Warning	OAX	Cass, Douglas, Lancaster, Otoe, Sarpy	42 min
Jun 26, 8:41 PM CDT	Severe Thunderstorm Warning	OAX	Gage, Jefferson, Johnson, Lancaster, Otoe, Saline	64 min
Jun 26, 9:30 PM CDT	Severe Thunderstorm Warning	OAX	Gage, Johnson, Pawnee	45 min
Jun 26, 9:31 PM CDT	Severe Thunderstorm Warning	OAX	Otoe	44 min
Jun 26, 9:33 PM CDT	Tornado Warning	OAX	Gage, Johnson, Pawnee	27 min
Jun 26, 9:47 PM CDT	Severe Thunderstorm Warning	OAX	Johnson, Nemaha, Otoe, Richardson	43 min
Jun 26, 9:47 PM CDT	Tornado Warning	OAX	Johnson, Nemaha, Pawnee	28 min
Jun 26, 10:08 PM CDT	Severe Thunderstorm Warning	OAX	Johnson, Pawnee, Richardson	67 min
Jun 26, 10:22 PM CDT	Severe Thunderstorm Warning	OAX	Nemaha, Richardson	38 min

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 1.0 hours before the alert went out and 112 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: 2873 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 501 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 248 m²/s²
0-3 km storm-relative helicity: 308 m²/s²
Significant tornado parameter: 6.2
Supercell composite: 26.5

Open this sounding in Storm Lab

The text

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

478 
WWUS20 KWNS 270102
SEL3
SPC WW 270102
NEZ000-270500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 563
NWS STORM PREDICTION CENTER NORMAN OK
805 PM CDT SUN JUN 26 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

       EXTREME SOUTHEASTERN NEBRASKA

EFFECTIVE THIS SUNDAY NIGHT FROM 805 PM UNTIL MIDNIGHT CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 20 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 30 MILES WEST OF BEATRICE
NEBRASKA TO 50 MILES EAST OF BEATRICE NEBRASKA.  FOR A COMPLETE
DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE
(WOUS64 KWNS WOU3).

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...CONTINUE...WW 555...WW 556...WW
559...WW 560...WW 561...WW 562...

DISCUSSION...SUPERCELLS DEVELOPING ON TAIL END OF MCS WILL HAVE THE
POTENTIAL TO PRODUCE ISOLATED TORNADOES...LARGE HAIL AND DAMAGING
WIND OVER SERN NEB THIS EVENING.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 29035.


...DIAL

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 26, 7:25 PM CDT	Mesoscale Discussion	SPC	Arthur, Blaine, Box Butte, Cherry, Garden, Grant and 7 more	65 min
Jun 26, 7:56 PM CDT	Severe Thunderstorm Watch	SPC	Arthur, Blaine, Cherry, Custer, Deuel, Garden and 9 more	7 hr
Jun 26, 11:33 PM CDT	Mesoscale Discussion	SPC	Boone, Buffalo, Garfield, Greeley, Hall, Hamilton and 7 more	57 min

Nearby

Tornado Watches in Nebraska, 2011 Every tornado watch in 2011

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.