Alert archive / Nebraska / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 303, NWS North Platte, NE

August 17, 2011Cherry County, Nebraska

NWS North Platte, NE issued this severe thunderstorm warning at Aug 17, 2011, 4:14 PM MDT for Cherry County, Nebraska. It was in force for 61 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 17, 2011, 4:14 PM MDT (22:14 UTC)
Expired
Aug 17, 2011, 5:15 PM MDT
In force
61 min
Issued by
NWS North Platte, NE
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Cherry County, NE

The radar

The North Platte radar (KLNX), 94 km from the middle of the area, began a volume at 22:17 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 was reported inside it

TimeReportWhereRemark
Aug 17, 5:00 PM MDTHAIL 2.536 Nnw Mullen, NE
Aug 17, 5:21 PM MDTHAIL 1.2536 Nw Mullen, NE

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 46 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 17, 2:37 PM MDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 10.2 hours before the alert went out and 180 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, N. Platte/Lee Bi, NE at 12:00Z on 2011-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 434 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, N. Platte/Lee Bi, NE at 12:00Z on 2011-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 35 square meters per square second.1939587897Sfc1 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
434 J/kg
Mixed-layer CIN
-108 J/kg
Mixed-layer LCL
696 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

538 
WUUS53 KLBF 172214
SVRLBF
NEC031-172315-
/O.NEW.KLBF.SV.W.0303.110817T2214Z-110817T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORTH PLATTE NE
414 PM MDT WED AUG 17 2011

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN CHERRY COUNTY IN NORTH CENTRAL NEBRASKA...

* UNTIL 515 PM MDT/615 PM CDT/

* AT 412 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
  LOCATED ALONG A LINE EXTENDING FROM NENZEL TO STEER CREEK
  CAMPGROUND TO INTERSECTION OF HIGHWAY 61 AND SURVEY VALLEY ROAD...
  AND MOVING EAST AT 25 MPH.

* LOCATIONS IMPACTED INCLUDE...
  STEER CREEK CAMPGROUND...KILGORE...ROUND LAKE...ANDERSON BRIDGE
  STATE WILDLIFE MANAGEMENT AREA...CROOKSTON...MERRITT RESERVOIR
  DAM...HIGHWAY 97 CROSSING THE NIOBRARA RIVER AND HIGHWAY 83 MILE
  MARKER 220.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 4273 10066 4234 10137 4243 10200 4301 10135
      4300 10055
TIME...MOT...LOC 2215Z 270DEG 20KT 4294 10106 4272 10115
          4239 10176
WIND...HAIL 60MPH 1.00IN

$$

SPRINGER
1 follow-up statement
819 
WWUS53 KLBF 172238
SVSLBF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
438 PM MDT WED AUG 17 2011

NEC031-172315-
/O.CON.KLBF.SV.W.0303.000000T0000Z-110817T2315Z/
CHERRY NE-
438 PM MDT WED AUG 17 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHERN
CHERRY COUNTY UNTIL 515 PM MDT/615 PM CDT/...

AT 535 PM CDT/435 PM MDT/...NATIONAL WEATHER SERVICE DOPPLER RADAR
INDICATED A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING LARGE
DESTRUCTIVE HAIL UP TO TENNIS BALL SIZE...AND DAMAGING WINDS IN
EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
FROM CROOKSTON TO ANDERSON BRIDGE STATE WILDLIFE MANAGEMENT AREA TO
ROUND LAKE...MOVING EAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  CROOKSTON...HIGHWAY 97 CROSSING THE NIOBRARA RIVER...MERRITT
  RESERVOIR DAM AND HIGHWAY 83 MILE MARKER 220.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THESE ARE DANGEROUS STORMS. IF YOU ARE IN THEIR PATH...PREPARE
IMMEDIATELY FOR LARGE DESTRUCTIVE HAIL CAPABLE OF PRODUCING
SIGNIFICANT DAMAGE. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 4273 10066 4234 10137 4243 10200 4301 10135
      4300 10055
TIME...MOT...LOC 2238Z 260DEG 30KT 4298 10078 4276 10087
          4244 10149
WIND...HAIL 60MPH 2.50IN

$$

SPRINGER

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 North Platte, NE wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 17, 2:00 PM MDT, 2 hours 14 minutes earlier.

Area forecast discussion, Aug 17, 2:00 PM MDT, 2 hours 14 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
3 PM CDT WED AUG 17 2011

.SYNOPSIS...

    AT 19Z...SURFACE ANALYSIS SHOWED LOW PRESSURE CENTERED IN
EXTREME SOUTHEAST MONTANA WITH A BOUNDARY EXTENDING INTO NORTHWEST
NEBRASKA. SATELLITE DERIVED PRECIPITABLE WATER SHOWED A PLUME OF
25-35MM PUSHING THROUGH WESTERN NEBRASKA AND ACROSS WESTERN
NEBRASKA. DERIVED LIFTED INDICES IN THAT AREA WERE -5C TO -7C. ONE
COULD SEE FIELDS OF CUMULUS CLOUDS BOTH OPEN CELLED AND IN STREETS
IN A 70 MILE WIDE SWATH FROM NEAR MERRIMAN AND VALENTINE TO NORTH
PLATTE AND IMPERIAL.
&&

.SHORT RANGE...TONIGHT THROUGH THURSDAY NIGHT.

    FOR TONIGHT...ALL CURRENT INDICATIONS DISCUSSED IN THE SYNOPSIS
ARE PRESENT TO LIGHT OFF CONVECTION IN NORTHWEST AND WEST CENTRAL
NEBRASKA ALONG THE SURFACE BOUNDARY WITH SUBSEQUENT PROPAGATION TO
THE SOUTHEAST. FOR CONVECTION THAT DOES DEVELOP...THERE IS LITTLE
DOUBT THAT INSTABILITY AND VERTICAL WIND PROFILES AND 0-6KM BULK
SHEAR IS SUFFICIENT TO SUPPORT LARGE HAIL AND POSSIBLY DAMAGING
WIND. THE MOISTURE WILL ALSO SUPPORT INTENSE RAINFALL FOR AT LEAST
BRIEF PERIODS. THERE IS STILL SOME UNCERTAINTY REGARDING THE
TIMING...EXTENT AND PATH OF CONVECTION.

    A BULGE IN THE DRY LINE WILL PUSH INTO WESTERN NEBRASKA
THURSDAY. VERY UNSTABLE CONDITIONS ARE AGAIN EXPECTED AHEAD OF IT.
BECAUSE OF TIMING...MOST OF THE SEVERE WEATHER IS EXPECTED TO BE
EAST OF A VALENTINE TO NORTH PLATTE LINE.

.MEDIUM RANGE...FRIDAY AND SATURDAY.

    WITH THE FRONT STALLING ALONG THE EASTERN SLOPE AND ACROSS
SOUTHERN KANSAS...SEVERE WEATHER IS POSSIBLE AGAIN FRIDAY AND
SATURDAY.

.EXTENDED...SUNDAY THROUGH WEDNESDAY.

    WITH A SURFACE TROUGH CONTINUING ON THE HIGH PLAINS...THERE IS
JUSTIFICATION FOR KEEPING A MENTION OF THUNDERSTORMS IN THE FORECAST
THROUGH AT LEAST SUNDAY NIGHT.

    AN UPPER RIDGE WILL BUILD BACK INTO THE SOUTHWEST. THIS SHOULD
RESULT IN DRY AND VERY WARM CONDITIONS MONDAY THROUGH WEDNESDAY.
EXTENDED MODELS ARE ON THE SAME PAGE WITH THAT SCENARIO. THE
LATEST STATISTICAL OUTPUT FROM THE GFS HAS KICKED HIGH TEMPERATURES
UP AROUND 10F FROM THE PREVIOUS RUN. HIGHS IN THE 90S WOULD FIT WITH
THE POSITION AND STRENGTH OF THE UPPER RIDGE...SO WE WILL NUDGE
TEMPERATURES UP IN THE FORECAST.
&&

.AVIATION...

    AVIATION CONCERNS THROUGH 18Z THURSDAY DEAL WITH THUNDERSTORM
CHANCES THIS EVENING AND OVERNIGHT AS WELL AS MVFR/IFR CEILINGS AND
VISIBILITIES THURSDAY MORNING.

    IN TERMS OF THUNDERSTORM CHANCES...A WEAK UPPER LEVEL
DISTURBANCE WILL MOVE ACROSS NEBRASKA LATER THIS AFTERNOON AND THIS
EVENING. AS THIS OCCURS...THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER
THE NEBRASKA PANHANDLE AND WESTERN NEBRASKA THEN MOVE EAST. AS THE
LOW LEVEL WINDS INCREASE FROM THE SOUTH TONIGHT...THIS CONVECTION
SHOULD CONTINUE AS IT MOVES EAST AND EXIT THE AREA BY THURSDAY
MORNING. WITH A SURFACE FRONT SITUATED TO THE SOUTH OVER KANSAS...DO
EXPECT TO SEE PLENTIFUL LOW LEVEL MOISTURE SURGING NORTH INTO
WESTERN NEBRASKA. HAVE INCLUDED LOWERED CEILINGS AND VISIBILITIES IN
THE FORECAST FOR KLBF...BUT CONFIDENCE IS LOWER ON THIS MOISTURE
MAKING IT AS FAR NORTH AS KVTN SO WILL KEEP VFR
CEILINGS/VISIBILITIES AT THAT LOCATION.
&&

.FIRE WEATHER...

    WEATHER CONDITIONS ON THURSDAY AFTERNOON WILL REACH NEAR
CRITICAL LEVELS...MAINLY WEST OF HIGHWAY 61. AFTERNOON RELATIVE
HUMIDITY LEVELS IN THESE LOCATIONS ARE EXPECTED TO DROP TO AROUND 15
PERCENT OR LOWER AS DRIER AIR SURGES EAST BEHIND A FRONTAL BOUNDARY.
THIS DRIER AIR WILL ALLOW FOR DEEPER MIXING AND THUS EXPECTING
TEMPERATURES TO RISE INTO THE LOW 90S. EAST OF HIGHWAY
61...EXPECTING RELATIVE HUMIDITY PERCENTAGES IN THE 20S...BUT IF THE
DRIER AIR PROGRESSES FURTHER EAST THAN ANTICIPATED...COULD GET THESE
LOWER HUMIDITY LEVELS TO NEAR HIGHWAY 83. THE LIMITING FACTOR WITH
REACHING CRITICAL FIRE WEATHER CONDITIONS IS WINDS AS THEY LOOK TO
BE STAY UNDER 15KTS FROM THE NORTHWEST THROUGHOUT THE DAY. WILL
MONITOR THESE TRENDS AS AN UPWARD SHIFT IN EXPECTED WINDS WOULD
LIKELY BRING ABOUT CRITICAL FIRE WEATHER CONDITIONS IN SOME
LOCATIONS.
&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.

SHORT RANGE AND MEDIUM RANGE/EXTENDED...SPRINGER
AVIATION/FIRE WEATHER...BROOKS
Hazardous weather outlook, Aug 17, 2:55 PM MDT, 1 hour 19 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORTH PLATTE NE
355 PM CDT WED AUG 17 2011

NEZ004>010-022>029-035>038-056>059-069>071-094-182100-
SHERIDAN-EASTERN CHERRY-KEYA PAHA-BOYD-BROWN-ROCK-HOLT-GARDEN-
GRANT-HOOKER-THOMAS-BLAINE-LOUP-GARFIELD-WHEELER-ARTHUR-MCPHERSON-
LOGAN-CUSTER-DEUEL-KEITH-PERKINS-LINCOLN-CHASE-HAYES-FRONTIER-
WESTERN CHERRY-
355 PM CDT WED AUG 17 2011 /255 PM MDT WED AUG 17 2011/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WESTERN AND
NORTH CENTRAL NEBRASKA.

.DAY ONE...TONIGHT.

SEVERE THUNDERSTORMS ARE POSSIBLE THROUGH TONIGHT WEST OF HIGHWAY
183 FROM SPRINGVIEW TO ANSLEY.

THUNDERSTORMS INITIATING ACROSS THE NEBRASKA PANHANDLE WILL MOVE
EAST INTO WESTERN AND CENTRAL NEBRASKA THIS EVENING. LARGE HAIL
AND DAMAGING WINDS ARE THE MAIN THREATS. IN ADDITION...WEST OF A
LINE FROM NORTH PLATTE TO VALENTINE THERE IS A THREAT FOR ISOLATED
TORNADOES THROUGH EARLY EVENING.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

ANOTHER ROUND OF SEVERE THUNDERSTORMS ARE POSSIBLE THURSDAY
AFTERNOON AND THURSDAY NIGHT EAST OF A LINE FROM VALENTINE TO
BROKEN BOW. LARGE HAIL AND DAMAGING WINDS ARE THE MAIN
THREATS...WHILE THERE IS A THREAT FOR AN ISOLATED TORNADO.

DRY AIR WILL SURGE EAST INTO THE PANHANDLE AND WESTERN NEBRASKA
THURSDAY AFTERNOON. THIS DRY AIR...COMBINED WITH WARM
TEMPERATURES IN THE LOWER AND MID 90S WILL LEAD TO VERY HIGH FIRE
DANGER OVER THE EASTERN PANHANDLE.

SEVERE THUNDERSTORMS ARE POSSIBLE FRIDAY AFTERNOON AND FRIDAY
NIGHT SOUTH OF A LINE FROM ANTIOCH TO BRADY...THEN AGAIN ON
SATURDAY AND SATURDAY NIGHT WITH THE GREATEST THREAT FOR SEVERE
STORMS SOUTH OF INTERSTATE 80.

.SPOTTER INFORMATION STATEMENT...

SPOTTER GROUPS SHOULD BE PREPARED FOR ACTIVATION THROUGH MID
EVENING WEST OF HIGHWAY 83 FROM VALENTINE TO NORTH PLATTE.

&&

THIS PRODUCT IS NOW AVAILABLE...ALONG WITH OTHER WEATHER...
HYDROLOGICAL AND CLIMATOLOGICAL INFORMATION...AT
HTTP://WWW.WEATHER.GOV/NORTHPLATTE

BROOKS

In the hours before

Local storm report, Aug 17, 1:55 PM MDT, 2 hours 19 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
255 PM CDT WED AUG 17 2011

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

0758 PM     TORNADO          8 NNW AINSWORTH         42.66N 99.92W
08/11/2011                   BROWN              NE   LAW ENFORCEMENT

            SHERIFF DEPUTY REPORTED BRIEF TORNADO TOUCHED DOWN IN AN
            OPEN FIELD WITH NO DAMAGE

&&

TKECK
Special weather statement, Aug 17, 3:26 PM MDT, 48 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
426 PM CDT WED AUG 17 2011

NEZ094-172230-
WESTERN CHERRY NE-
326 PM MDT WED AUG 17 2011

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN CHERRY COUNTY UNTIL 430
PM MDT...

AT 322 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 6 MILES EAST OF HIGHWAY 61 CROSSING THE NIOBRARA
RIVER...OR 32 MILES EAST OF GORDON...MOVING EAST AT 25 MPH.

HAIL UP TO THE SIZE OF NICKELS AND WIND GUSTS EXCEEDING 50 MPH ARE
EXPECTED WITH THIS STORM...ALONG WITH FREQUENT DANGEROUS LIGHTNING.

LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...
  MEDICINE LAKE...
  ELI...
  SCHOOLHOUSE LAKE...
  STEER CREEK CAMPGROUND...
  NENZEL...
  KILGORE...
  CODY...

THIS STORM MAY INTENSIFY...AND A SEVERE THUNDERSTORM WATCH IS IN
EFFECT FOR THIS AREA. BE CERTAIN TO MONITOR LOCAL RADIO AND TV
STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

SPRINGER
Special weather statement, Aug 17, 4:00 PM MDT, 14 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
400 PM MDT WED AUG 17 2011

NEZ005-094-172300-
EASTERN CHERRY NE-WESTERN CHERRY NE-
400 PM MDT WED AUG 17 2011

...SIGNIFICANT WEATHER ADVISORY FOR CHERRY COUNTY UNTIL 500 PM
MDT/600 PM CDT/...

AT 459 PM CDT/359 PM MDT/...NATIONAL WEATHER SERVICE DOPPLER RADAR
WAS TRACKING STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 8 MILES
NORTH OF NENZEL TO 6 MILES NORTH OF SCHOOLHOUSE LAKE TO 8 MILES NORTH
OF DIPPING VAT MEADOW...AND MOVING EAST AT 30 MPH.

HAIL UP TO THE SIZE OF NICKELS AND WIND GUSTS EXCEEDING 50 MPH ARE
EXPECTED WITH THESE STORMS...ALONG WITH FREQUENT DANGEROUS LIGHTNING.

LOCATIONS NEAR THE PATH OF THESE STORMS INCLUDE...
  VALENTINE...
  NENZEL...
  SCHOOLHOUSE LAKE...
  KILGORE...
  STEER CREEK CAMPGROUND...
  ROUND LAKE...
  ANDERSON BRIDGE STATE WILDLIFE MANAGEMENT AREA...
  CROOKSTON...
  HIGHWAY 97 CROSSING THE NIOBRARA RIVER...
  SPECKEL MEIR LAKE...
  MERRITT RESERVOIR DAM...
  SCHLAGEL CREEK STATE WILDLIFE MANAGEMENT AREA...
  HIGHWAY 61 MILE MARKER 190...
  HIGHWAY 83 MILE MARKER 220...
  HIGHWAY 97 MILE MARKER 110...
  HIGHWAY 12 MILE MARKER 10...

THESE STORMS MAY INTENSIFY...AND A SEVERE THUNDERSTORM WATCH IS IN
EFFECT FOR THIS AREA. BE CERTAIN TO MONITOR LOCAL RADIO AND TV
STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

SPRINGER

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 4:51 PM MDTTornado WarningLBFCherry39 min
Aug 17, 5:18 PM MDTSevere Thunderstorm WarningLBFCherry57 min
Aug 17, 5:40 PM MDTTornado WarningLBFCherry35 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 2011Every severe thunderstorm warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.