Severe Thunderstorm Warning 38, NWS North Platte, NE

000 
WWUS53 KLBF 210102
SVSLBF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
802 PM CDT FRI APR 20 2007

NEC085-111-210130-
/O.CON.KLBF.SV.W.0038.000000T0000Z-070421T0130Z/
LINCOLN NE-HAYES NE-
802 PM CDT FRI APR 20 2007

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR NORTHEASTERN HAYES AND CENTRAL LINCOLN COUNTIES...

AT 753 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED 8 MILES NORTHEAST OF HAYES CENTER STATE WILDLIFE MANAGEMENT
AREA...OR ABOUT 15 MILES NORTHEAST OF HAYES CENTER...MOVING NORTHEAST
AT 30 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  HIGHWAY 83 MILE MARKER 60 BY 810 PM CDT...
  HIGHWAY 83 MILE MARKER 70 BY 825 PM CDT...
  9 MILES SOUTHEAST OF LAKE MALONEY STATE RECREATION AREA BY 830 PM
  CDT...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

LAT...LON 4050 10107 4049 10078 4070 10077 4106 10049
      4106 10070 4104 10093

$$

CDC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
337 PM CDT FRI APR 20 2007

...FORECAST CHALLENGES ARE TIMING AND TRACK OF UPPR SYSTEM THROUGH
FRIDAY AND ASSOCIATED SEVERE CHANCES AND PRECIPITATION TYPE ON THE
BACKSIDE OF THE EXITING SYSTEM FRIDAY...

.NEAR TERM (TONIGHT THROUGH SUNDAY NIGHT)...MAIN FORECASTING
CONCERNS HINGE ON ELEVATED CONVECTION CONCERNS TONIGHT...AND SVR
POTENTIAL AND POP CHANCES FOR TOMORROW. FOR TONIGHT...18Z SOUNDING
INDICATING A VERY STRONG SFC BASED CAP OVR LBF...BUT LOADS OF
INSTABILITY ALOFT. INSTABILITY ALREADY EVIDENT TO THE NORTH ACROSS
SODAK WITH ABUNDANT ONGOING TSRAS NOTED. LOWERED POPS SLIGHTLY
TONIGHT...AS AM EXPECTING ONLY ISOLATED COVERAGE. LATEST NAM
INDICATING A LACK OF AN H5 SHORTWAVE THIS EVENING SO A TRIGGER
LARGELY ABSENT. BEST FORCING FOR CONVECTION SEEMS TO BE LOW LEVEL
MOISTURE CONVERGENCE AND WILL HAVE THE EVE SHIFT MONITOR CLOSELY.
MAIN CONVECTION AND SVR EVENT ARRIVES ON SATURDAY AS THE UPPR LOW
CROSSES THE SRN ROCKIES. BY AFTERNOON...AN ELONGATED SURFACE LOW
WILL DEVELOP ACROSS THE PANHANDLE AND SWRN SD...WITH A WARM FRONT
EXTENDING ENEWD INTO EASTERN SOUTH DAKOTA. LATEST NAM AND SPC
DISCUSSION HINTS AT GREATEST SVR THREATS OVR ERN SD AND KS/W TX IN
VICINITY OF THE JET (KS/W TX) AND ERN SD (HIGH VGP AND LL HELICITY).
IN BETWEEN STILL THINKING A LINE OF THUNDERSTORMS WITH EMBEDDED
SUPERCELLS. ALL OF THIS CONVECTION WILL CONGEAL INTO A MCS
OVERNIGHT. SPED UP THE ENDING OF PRECIPITATION ON SUNDAY EVENING IN
THE ERN ZONES AS MODEL SOLUTIONS ARE FASTER WITH THE UPPR LOW.

.MONDAY AND MONDAY NIGHT...TRANQUIL CONDS MONDAY WILL GIVE WAY TO
ANOTHER ROUND OF STRONG TO SVR TSRAS ON MONDAY AFTERNOON AND MONDAY
NIGHT AS THE NEXT CLOSED LOW DRIVES ACROSS THE FOUR CORNERS. WILL
INCREASE POPS MONDAY AFTERNOON AND MONDAY NIGHT IN ALL
LOCS.

.LONG TERM (TUESDAY THROUGH FRIDAY)...MINIMAL CHANGES MADE TO
ONGOING PACKAGE...OTHER THAN TO INCREASE POPS FOR TUESDAY INTO
WEDNESDAY AND TO COOL TEMPS. GFS AND EURO MODEL SOLUTIONS CONTINUE
TO INDICATE A MAJOR UPPR LVL LOW CROSSING THE CENTRAL PLAINS ON
TUESDAY AND WEDNESDAY. ONLY SLIGHT DIFFERENCES NOTED IN THE TRACK OF
THIS FEATURE...WITH THE GFS NORTH AND EURO SOUTH. THE EURO TRACK
FAVORS HIGHER POPS ACROSS THE SRN CWA AND GFS MORE NRLY AND CENTRAL
AREAS. AS MENTIONED EARLIER...TRENDED POPS UP SOME ACROSS THE BOARD.
AND WOULDNT BE SURPRISED IF THEY NEED FURTHER ADJUSTMENT UPWARD
THIS WEEKEND. BEYOND WEDNESDAY...SOME LOW PRECIPITATION CHANCES MAY
BE NECESSARY AS A WAVE CROSSES THE NRN PLAINS...PER GFS SOLN. LOW
CONFIDENCE IN THIS SCENARIO AT THIS JUNCTURE...SO WILL GO WITH DRY
FOR NOW.

&&

.AVIATION...
ISOLATED TO SCATTERED MVFR CEILINGS WILL PERSIST ACROSS PORTIONS OF
THE 098 TWEB ROUTE LATE THIS AFTERNOON INTO THE EVENING HOURS.
ISOLATED SHOWERS AND THUNDERSTORMS WILL ALSO BE POSSIBLE MAINLY
ACROSS THE 098 TWEB ROUTE THROUGH THE LATE EVENING HOURS AND BRING
AREAS OF MVFR CEILINGS AND VSBYS DUE TO MODERATE RAINFALL. MVFR TO
ISOLATED IFR CONDITIONS ARE THEN EXPECTED TO EXPAND TO MUCH OF THE
NEBRASKA TWEB ROUTES DURING THE PRE-DAWN HOURS LASTING INTO THE LATE
MORNING HOURS WHEN CEILINGS ARE EXPECTED TO SCATTER TO VFR
CONDITIONS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE

&&

CLB/13

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORTH PLATTE NE
350 PM CDT FRI APR 20 2007

NEZ004>010-022>029-035>038-056>059-069>071-094-211200-
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-
350 PM CDT FRI APR 20 2007 /250 PM MDT FRI APR 20 2007/

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

.DAY ONE...TONIGHT.

ISOLATED THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE THIS EVENING
AND INTO THE EARLY MORNING HOURS ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA. WIDESPREAD SEVERE IS NOT EXPECTED...HOWEVER A FEW STORMS
MAY REACH SEVERE LIMITS AND PRODUCE LARGE HAIL. THIS MAIN THREAT
AREA FOR SEVERE THUNDERSTORM DEVELOPMENT IS NORTH OF HIGHWAY 2.
STRONGER STORMS MAY ALSO TRY AND FORM IN WESTERN KANSAS...AND MOVE
INTO SOUTWEST NEBRASKA THIS EVENING FORMING A SECONDARY AREA FOR
ISOLATED SEVERE THUNDERSTORM FORMATION.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

MOISTURE WILL BE WELL ESTABLISHED ACROSS THE AREA ON SATURDAY.
AS STRONG SYSTEM MOVING OUT OF THE CENTRAL ROCKIES WILL PROVIDE
THE ADDITIONAL INGREDIENTS OF STRONG LIFT AND INSTABILITY TO
PRODUCE MORE WIDESPREAD SEVERE WEATHER SATURDAY AFTERNOON AND
EVENING. SIMILARITIES EXIST WITH THE OUTBREAK IN LATE MARCH...WITH
LARGE HAIL...DAMAGING WIND GUSTS AND ISOLATED TORNADOES POSSIBLE.
THE AREA AT THE GREATEST RISK FOR SEVERE WEATHER AT THIS TIME
LOOKS TO BE ALONG AND WEST OF HIGHWAY 61.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED THROUGH TONIGHT.

&&

THIS PRODUCT IS NOW AVAILABLE...ALONG WITH OTHER WEATHER...
HYDROLOGICAL AND CLIMATE INFORMATION...AT
HTTP://WWW.CRH.NOAA.GOV/LBF(ALL LOWERCASE)

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