Severe Thunderstorm Warning 136, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
237 PM CDT TUE JUN 20 2006

...FORECAST CHALLENGE IS PRECIPITATION CHANCES THROUGH SATURDAY...

.DISCUSSION...
NEAR TERM (TONIGHT THROUGH FRIDAY)...MAIN FCSTING CHALLENGE IN THE
NEAR TERM IS PRECIPITATION CHANCES THROUGH FRIDAY AND SEVERE
POTENTIAL FOR TONIGHT. SFC ANALYSIS AND LAPS DATA AS OF 18Z
INDICATING A FRONTAL BOUNDARY RIGHT ON TOP OF LBF...EXTENDING NWD TO
ANW AND SWD INTO WRN KS. ANOTHER BOUNDARY EXTENDS WNWD FROM A SFC
LOW (WEST OF HILL CITY) TO SOUTH OF BURLINGTON AND LIMON COLORADO.
SHORTWAVE ENERGY ALREADY IMPACTING CENTRAL COLORADO AND ERN WYOMING
REFERENCED FROM WV IMAGERY AND ABUNDANT TOWERING CU FIELD IN THE VIS
SATELLITE. MOISTURE CONTINUES TO POOL ON THE BACK SIDE OF THE BEFORE
MENTIONED SFC FEATURE...AS DEW POINTS FOR LBF...OGA AND IML HAVE
SHOT UP INTO THE LWR 60S. LAPS DATA FROM 18Z INDICATING A BROAD
SWATH OF 2500J/KG CAPES FROM JUST NORTH OF LBF...TO IML AND OGA AS
WELL...WITH A STEADILY ERODING CAP. SFC TO H4 SHEAR VERY IMPRESSIVE
THIS AFTERNOON WITH BETTER THAN 50KTS OF SHEAR. TORNADO THREAT
APPEARS FAIRLY MINIMAL THOUGH AS 0-1 AND 0-3 KM HELICITIES NOT
OVERLY IMPRESSIVE AND BULK RICHARDSON NUMBERS INDICATE MORE OF A
WIND AND HAIL EVENT VS A TORNADIC ONE. REGARDLESS ANY CONVECTION
WHICH INTERACTS WITH THE BEFORE MENTIONED SFC FRONT WILL HAVE TO BE
MONITORED VERY CLOSELY FOR TORNADOES. LOW LEVEL JET WILL BE FOCUSED OVER SRN
NEBR OVERNIGHT...SO ONGOING CONVECTION SHOULD LAST WELL AFTER DARK.
WILL FOCUS HIGHEST POPS ACROSS THE SOUTH AND MENTION SEVERE THROUGH
MIDNIGHT.

DEJA VS FOR THE NEXT COUPLE OF DAYS AS THE HIGH PLAINS REMAINS IN
ZONAL FLOW ALOFT WITH THETA E RIDGING INTO THE FRONT RANGES OF
COLORADO AND WYOMING. HAVE PAINTED POPS FOR BOTH WEDNESDAY AND
THURSDAY...PRIMARILY DURING THE LATE AFTERNOON AND EVENING
HOURS...AS SHORTWAVES EMERGE FROM THE CENTRAL ROCKIES DURING THE
LATE AFTERNOON HOURS. SEVERE THREAT SHOULD REMAIN CONCENTRATED
ACROSS THE SRN HALF OF THE CWA AS THE FRONTAL BOUNDARY IS EXPECTED
TO ALIGN ACROSS THE NEBR/KS BORDER ON WEDNESDAY. WILL NEED TO SEE
WHERE THIS PARKS ITSELF WEDNESDAY...BEFORE ASSESSING THE SVR THREAT
FOR WEDNESDAY NIGHT. IN THE MEANTIME...HIGHEST POPS IN THE
SOUTH...WITH LOWER POPS IN THE NRN ZONES.

LONG RANGE (FRIDAY NIGHT THROUGH TUESDAY)...MAIN FORECASTING
CHALLENGES IN THE LONG TERM ARE PRECIPITATION CHANCES MAINLY FOR
FRIDAY NIGHT AND SATURDAY. UPPR PATTERN WILL BEGIN A SLOW TRANSITION
FROM ZONAL TO NWRLY THIS WEEKEND. THIS AMPLIFICATION...A RESULT OF
RIDGING IN THE WEST AND TROFING OVER THE GREAT LAKES...SHOULD
DIMINISH PRECIPITATION CHANCES FOR EARLY NEXT WEEK. FOR SATURDAY...A
TROF OF LOW PRESSURE WILL DIVE INTO THE UPPR MISSISSIPPI
VALLEY...FORCING A COLD FRONT THROUGH THE CWA FOR SATURDAY. BEST
CHANCES FOR PRECIPITATION OCCUR ALONG THE FRONT FOR SATURDAY...THEN
SUNDAY ACROSS THE FAR WESTERN ZONES ALONG THE THETA E RIDGE AXIS
OVER THE FRONT RANGES OF COLORADO AND WYOMING. NWRLY FLOW SHOULD
CARRY SOME OF THIS ACTIVITY INTO THE SRN PANHANDLE AND FAR SWRN
ZONES ON SUNDAY. DRY FCST RETAINED FOR MONDAY AND TUESDAY.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE

CLB

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
346 PM CDT TUE JUN 20 2006

NEZ004>010-022>029-035>038-056>059-069>071-094-212100-
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-
346 PM CDT TUE JUN 20 2006 /246 PM MDT TUE JUN 20 2006/

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

.DAY ONE...TONIGHT.

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORM DEVELOPMENT TONIGHT
SOUTH OF A LINE FROM HAY SPRINGS IN SHERIDAN COUNTY...TO ONEILL IN
HOLT COUNTY. AN UPPER LEVEL DISTURBANCE WILL LIFT NORTHEAST ACROSS
THE PANHANDLE AND WESTERN NEBRASKA THAT WILL HELP IGNITE STORM
DEVELOPMENT. LARGE HAIL AND DAMAGING WINDS ARE POSSIBLE. OVERNIGHT
THE STORMS MAY DEVELOP INTO A CLUSTER BRINGING ADDITIONAL RAINS TO
THE OUTLOOK AREA.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

THE CHANCE FOR SEVERE THUNDERSTORM DEVELOP WILL SHIFT SOUTHWARD ON
WEDNESDAY AS THE FRONT SLIPS SOUTH. ON WEDNESDAY THE GREATEST RISK
FOR SEVERE STORMS WILL FOCUS SOUTH ON INTERSTATE 80. THEN THURSDAY
AS THE FRONT MOVES FURTHER SOUTH SCATTERED THUNDERSTORMS WILL
REMAIN POSSIBLE...BUT SEVERE STORM DEVELOPMENT IS NOT EXPECTED
THROUGH NEXT MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED THIS EVENING.

&&

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

KECK