Alert archive / Nebraska / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 121, NWS Omaha, NE

June 17, 2009Seward County, Nebraska

NWS Omaha, NE issued this severe thunderstorm warning at Jun 17, 2009, 10:10 PM CDT for Seward County, Nebraska. It was in force for 35 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jun 17, 2009, 10:10 PM CDT (03:10 UTC)
Expired: Jun 17, 2009, 10:45 PM CDT
In force: 35 min
Issued by: NWS Omaha, NE
Area: Storm-based polygon

County Seward County, NE

The radar

The Omaha radar (KOAX), 82 km from the middle of the area, began a volume at 03:13 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
Jun 17, 9:04 PM CDT	Tornado Watch	SPC	3 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 3.2 hours before the alert went out and 81 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: 1256 J/kg
Mixed-layer CIN: -128 J/kg
Mixed-layer LCL: 1892 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 54 m²/s²
0-3 km storm-relative helicity: 169 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Omaha, NE wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 17, 3:45 PM CDT, 6 hours 25 minutes earlier.

Area forecast discussion, Jun 17, 3:45 PM CDT, 6 hours 25 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
345 PM CDT WED JUN 17 2009

.DISCUSSION...
WV IMAGERY AND 700MB PROFILERS SHOWING SHORTWAVE TROF MOVING ACROSS
WRN NEB RIDING UP AND OVER ESTABLISHED UPPER RIDGE SITUATED OVER THE
CNTRL/SRN HIGH PLAINS. LARGE SCALE LIFT BEING ENHANCED VIA RRQ OF
JET. MEANWHILE A TORNADIC SUPERCELL ALREADY HAS RUMBLED ACROSS SERN
NEB THIS AFTERNOON IN ASSOCIATION WITH A WARM FRONT ALONG THE NEB/KS
BORDER. LATEST SPC MESO-ANALYSIS IN THAT AREA SHOWED SBCAPES 4000J/KG
WITH EFFECTIVE SHEAR AROUND 55KT. OBVIOUS NEAR TERM CONCERN IS
ADDITIONAL SEVERE WEATHER TONIGHT. MODELS SUGGESTING BEST OVERLAP OF
MUCAPES/ESRH/EBWD WILL REMAIN OVER SERN NEB WELL INTO THE EVENING
HOURS...THUS ADDITIONAL TORNADIC STORMS ANTICIPATED. MODELS ARE SLOW
LIFTING THE FRONT OVERNIGHT AND IT APPEARS THE BNDRY WILL STALL ALONG
THE SD/NEB BORDER LATE THURSDAY AFTN AND THEREFORE WILL FOCUS THUNDER
POPS UP THERE. BY THURSDAY NIGHT...RATHER ILL-DEFINED SFC LOW HEADING
EAST ACROSS KS WILL EVENTUALLY DRAG ATTENDANT COLD FRONT INTO THE
CNTRL PLAINS. POTENT SHORTWAVE ENERGY/ASSOC LARGE SCALE LIFT MOVING
THRU AT THAT TIME MAY HELP KICK OFF ANOTHER ROUND OF SEVERE WEATHER
PER STRONG MLCAPE/DEEP LYR SHEAR. GRADUAL END TO ACTIVITY SHOULD
OCCUR THRU FRI FRIDAY AFTN. DRY ON SAT WITH UPPER RIDGE BUILDING
OVER THE PLAINS.

IN THE EXTENDED PERIODS...MEAN LARGE SCALE FLOW OVER THE CONUS
DEPICTS DIGGING WEST COAST TROF SUNDAY KICKING EASTWARD AN AMPLIFIED
UPPER RIDGE SITUATED OVER THE GREAT PLAINS. UPPER PATTERN EVENTUALLY
BECOMES LESS PROGRESSIVE WHEN MASSIVE AREA OF HIGH PRESSURE
RETROGRADES AND SETTLES IN OVER THE CNTRL/SRN PLAINS. MAIN PROBLEM
HERE IS PINNING DOWN FOCUS FOR CONVECTIVE ACTIVITY GIVEN PRETTY WEAK
UPPER LVL SUPPORT. GFS/ECM IN DECENT AGREEMENT DEPICTING A WARM FRONT
SLOWLY LIFTING OVER THE CNTRL PLAINS SUNDAY AND SUNDAY NIGHT WHILE
CAA MOVES SWD THRU THE DAKOTAS. MODELS PROG THIS COLD FRONT
EVENTUALLY STALLING IN RESPONSE TO AFOREMENTIONED RETROGRADING UPPER
HIGH INTO THE PLAINS. AMPLE MOISTURE APPEARS TO BE ON TAP FOR
CONVECTION...BUT AT THIS POINT HAVE LOW CONFIDENCE MONDAY THRU
WEDNESDAY WHERE ANY ACTIVITY WILL FIRE. OTHERWISE...ABOVE NORMAL
TEMPS ON TAP DURING THE PD FOR THE CWA.

&&

.AVIATION...
FOR TAF SITES KOFK/KOMA/KLNK VALID THROUGH 18/18Z.

MAIN AVIATION CONCERN IS POTENTIAL STRONG/SEVERE CONVECTIVE ACTIVITY
OVER SERN NEB THIS EVENING. FOCUS FOR ACTIVITY IS WARM FRONT ALONG
KS/NEB BORDER. THE BEST TIME FOR SVR TSRA AT
KLNK/KOMA APPEARS TO BE BTWN 18/00Z-06...BUT SCATTERED NATURE OF
STORMS RESULTING IN LOW OVERALL CONFIDENCE.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.

&&

DEE

Hazardous weather outlook, Jun 17, 5:11 PM CDT, 4 hours 59 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
511 PM CDT WED JUN 17 2009

IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034-
042>045-050>053-065>068-078-088>093-180500-
ANTELOPE-BOONE-BURT-BUTLER-CASS-CEDAR-COLFAX-CUMING-DODGE-DOUGLAS-
FREMONT IA-GAGE-HARRISON IA-JEFFERSON-JOHNSON-KNOX-LANCASTER-MADISON-
MILLS IA-MONONA IA-MONTGOMERY IA-NEMAHA-OTOE-PAGE IA-PAWNEE-PIERCE-
PLATTE-POTTAWATTAMIE IA-RICHARDSON-SALINE-SARPY-SAUNDERS-SEWARD-
SHELBY IA-STANTON-THURSTON-WASHINGTON-WAYNE-
511 PM CDT WED JUN 17 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN NEBRASKA AND SOUTHWEST
IOWA.

.DAY ONE...TONIGHT AND THURSDAY

A VERY UNSTABLE ENVIRONMENT COUPLED WITH DEEP LAYER SHEAR WILL MAKE
SEVERE THUNDERSTORM DEVELOPMENT PROBABLE ANYWHERE OVER THE OUTLOOK
AREA TONIGHT...WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS.
OVER SOUTHEAST NEBRASKA THOUGH...THE THREAT FOR TORNADIC
THUNDERSTORMS ARE ESPECIALLY HIGH DURING THE EVENING HOURS.

THE FOCUS FOR THE SEVERE STORM DEVELOPMENT IS REVOLVING AROUND A
QUASI-STATIONARY WARM FRONT ALONG THE NEBRASKA...KANSAS BORDER. THE
FRONT WILL EVENTUALLY MAKE ITS WAY NORTHWARD INTO THE DAKOTAS LATE
THURSDAY AFTERNOON ALONG WITH THE THUNDERSTORM ACTIVITY.

.DAYS TWO THROUGH SEVEN...THURSDAY NIGHT THROUGH WEDNESDAY

THERE IS A SLIGHT CHANCE ADDITIONAL SEVERE THUNDERSTORMS THURSDAY
NIGHT OVER THE OUTLOOK AREA IN ASSOCIATION WITH A COLD FRONT
ADVANCING INTO THE CENTRAL PLAINS. OTHERWISE...THUNDERSTORM
CHANCES CONTINUE ON FRIDAY...AS WELL AS SATURDAY NIGHT THROUGH
MONDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY THIS EVENING ACROSS MUCH OF THE
OUTLOOK AREA...PARTICULARLY IN COUNTIES SOUTH OF I-80.

DEE

In the hours before

Local storm report, Jun 17, 9:24 PM CDT, 46 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
924 PM CDT WED JUN 17 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0905 PM     HAIL             5 N WAUSA               42.57N 97.54W
06/17/2009  E1.75 INCH       KNOX               NE   STORM CHASER

&&

DEE

Local storm report, Jun 17, 9:25 PM CDT, 45 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
925 PM CDT WED JUN 17 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0920 PM     HAIL             2 SW MEADOW GROVE       42.01N 97.76W
06/17/2009  M0.88 INCH       MADISON            NE   TRAINED SPOTTER

&&

ACURTIS

Local storm report, Jun 17, 9:37 PM CDT, 33 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
937 PM CDT WED JUN 17 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0935 PM     HAIL             6 N BATTLE CREEK        42.09N 97.60W
06/17/2009  M1.25 INCH       MADISON            NE   TRAINED SPOTTER

&&

ACURTIS

Local storm report, Jun 17, 9:50 PM CDT, 20 minutes before

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Local storm report, Jun 17, 9:58 PM CDT, 12 minutes before

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Local storm report, Jun 17, 10:01 PM CDT, 9 minutes before

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    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 17, 8:07 PM CDT	Severe Thunderstorm Warning	OAX	Antelope	53 min
Jun 17, 8:15 PM CDT	Severe Thunderstorm Warning	OAX	Burt, Washington	31 min
Jun 17, 8:50 PM CDT	Severe Thunderstorm Warning	OAX	Cedar, Knox, Pierce	55 min
Jun 17, 8:59 PM CDT	Severe Thunderstorm Warning	OAX	Antelope, Madison, Pierce	61 min
Jun 17, 9:26 PM CDT	Tornado Warning	OAX	Madison, Pierce	34 min
Jun 17, 9:46 PM CDT	Tornado Warning	OAX	Madison, Stanton	44 min
Jun 17, 9:49 PM CDT	Severe Thunderstorm Warning	OAX	Cedar, Madison, Pierce, Stanton, Wayne	56 min
Jun 17, 10:23 PM CDT	Severe Thunderstorm Warning	OAX	Cuming, Stanton, Thurston, Wayne	52 min
Jun 18, 4:21 AM CDT	Severe Thunderstorm Warning	OAX	Antelope, Knox	39 min
Jun 18, 4:49 AM CDT	Severe Thunderstorm Warning	OAX	Cedar, Knox, Pierce	41 min
Jun 18, 5:09 AM CDT	Severe Thunderstorm Warning	OAX	Cedar, Pierce, Wayne	51 min
Jun 18, 5:49 AM CDT	Severe Thunderstorm Warning	OAX	Thurston, Wayne	28 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 2009 Every severe thunderstorm warning in 2009

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.