Hail in Nebraska, August 26 to 27, 2008

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
511 PM CDT TUE AUG 26 2008

.UPDATE...
UPDATED FOR SEVERE THUNDERSTORM WATCH.

&&

.PREV DISCUSSION... /ISSUED 326 PM CDT TUE AUG 26 2008/

SYNOPSIS...
UPPER LEVEL WAVE MOVING INTO MONTANA THIS AFTERNOON AS SEEN IN IR
PUSHING A COLD FRONT INTO THE NORTHERN PLAINS. SURFACE TROUGH
THROUGH THE EASTERN PLAINS OF WYOMING AND COLORADO.

DISCUSSION...
MODELS IN GOOD AGREEMENT IN NEAR TERM. STRONG WAA THIS AFTERNOON
AND GOOD MIXING. TEMPERATURES SLOW TO REBOUND AFTER YET ANOTHER
MORNING OF LOW CLOUDS. MODEL SOUNDINGS INDICATING A STRONG CAP
OVER SOUTHWEST NEBRASKA. FROPA FOR NORTHWEST ZONES AROUND 00Z AND
DOWN SOUTH 6Z OR LATER. HAVE UPPED POPS OVER NORTHEN NEBRASKA THIS
EVENING WITH SCHC RETAINED SOUTH. PWATS CONTINUE 120% NORMAL
VALUES AROUND 1.00. STORM MOTIONS COMBINED WITH ABUNDANT MOISTURE
COULD PRODUCE SOME HIGH QPF. GFS HAS A SLOWER EVOLUTION WITH UPPER
SUPPORT LAGGING. THIS WILL HAVE TO BE WATCHED FOR LINGERING
CONVECTION WELL INTO WEDNESDAY. I PREFERRED THE FASTER PROGRESSION
WITH THE NAM AND HAVE TRENDED FORECAST TOWARDS IT. WEDNESDAY
TEMPERATURES SOME 5 TO 10 DEGREES COOLER ACROSS THE FORECAST AREA
AND BREEZY.

IN THE EXTENDED THE RIDGE BUILDS IN TOWARDS THE WEEKEND WITH
TEMPERATURES INCREASING INTO THE UPPER 80S WITH SOME 90S NORTH.
GFS TRENDING TOWARDS ECMWF IN LATER PERIODS WITH DEEPER TROUGH
BUILDING INTO WESTERN CONUS AND MOVING ACROSS THE NORTHERN PLAINS
AROUND THE FIRST OF THE WEEK. HAVE LEFT FORECAST DRY FOR NOW WITH
UNCERTATINTY BUT HAVE FOLLOWED A DOWNWARD TREND IN FORECAST HIGH
TEMPERATURES NEAR HPC.

AVIATION...
AN AREA OF LOW PRESSURE IS STRENGTHENING OVER THE CENTRAL AND
NORTHERN HIGH PLAINS...AHEAD OF AN UPPER LEVEL DISTURBANCE LOCATED
OVER THE NORTHERN ROCKIES. THIS WILL FAVOR STRONG GUSTY WINDS
THROUGH THE AFTERNOON...WHICH WILL SLACKEN AFTER SUNSET AS THE LOW
PRESSURE SYSTEM APPROACHES THE REGION. THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG A COLD FRONT ASSOCIATED WITH THE SFC LOW...AND WILL
LIKELY AFFECT THE KVTN TERMINAL BY 03Z. WINDS WILL THEN BECOME
NORTH/NORTHEASTERLY AFTER THE FRONTAL PASSAGE...WHICH WILL OCCUR
SHORTLY AFTER 06Z WEDNESDAY. SCT TO BKN MID LVL CLOUDINESS MAY OCCUR
AT BOTH THE KLBF AND KVTN TERMINALS BEHIND THE FRONT THROUGH
WEDNESDAY MORNING.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...WIND ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR NEZ005-
006-008-009-023>026-035>037-094.

SEVERE THUNDERSTORM WATCH UNTIL 11 PM CDT /10 PM MDT/ THIS
EVENING FOR NEZ004-005-022-023-094.

&&

POWER

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
517 PM CDT TUE AUG 26 2008

NEZ004>010-022>029-035>038-056>059-069>071-094-272230-
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-
517 PM CDT TUE AUG 26 2008 /417 PM MDT TUE AUG 26 2008/

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

.DAY ONE...TONIGHT.

A STRONG COLD FRONT WILL ADVANCE SOUTHEAST INTO WESTERN AND NORTH
CENTRAL NEBRASKA TONIGHT. AS IT ENCOUNTERS A WARM...MOIST...AND
MODERATELY UNSTABLE ATMOSPHERE...SCATTERED THUNDERSTORMS WILL
DEVELOP. THESE STORMS ARE EXPECTED TO EVOLVE INTO A BROKEN
LINE...POSING A RISK OF DAMAGING WINDS AND LARGE HAIL ALONG AND
WEST OF AN OGALLALA TO VALENTINE LINE. AS THE NIGHT
PROGRESSES...STORMS MAY INCREASE IN COVERAGE ACROSS THE REMAINDER
OF THE OUTLOOK AREA...THOUGH THE RISK FOR SEVERE WEATHER WILL
DECREASE BY MIDNIGHT.

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

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED ALONG AND WEST OF AN
OGALLALA TO VALENTINE LINE.

&&

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

GARNER