Tornadoes and Hail in Nebraska, June 25, 2010

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
350 PM CDT FRI JUN 25 2010

.DISCUSSION...
TONIGHT...TEMPERATURES WILL SLOWLY RETREAT FROM HIGHS IN THE 90S
FALLING TO JUST BELOW 70 IN SOME AREAS OVERNIGHT.  A FRONT WILL
REMAIN MOSTLY IN SOUTH DAKOTA AS SHOULD MOST THUNDERSTORMS THROUGH
LATE SATURDAY.

SATURDAY...HIGH TEMPERATURES WILL REACH NEAR TODAY/S VALUES AND
PACKED WITH NEARLY AS MUCH MOISTURE. MODELS INTERACT WITH THIS
MOISTURE DIFFERENTLY AND PRODUCE DIFFERENT THUNDERSTORM SCENARIOS.
THE GFS KEEPS MUCH OF THE THUNDERSTORM ACTIVITY TO THE NORTHEAST
PORTIONS OF THE CWA...ACROSS NORTH CENTRAL AND THEN EASTERN
NEBRASKA.  THE NAM HAS GREATER THUNDERSTORM DEVELOPMENT WITH STORMS
ON GOING IN THE MORNING AND SAGGING SOUTH WITH THE FRONTAL SYSTEM.
CAPES ARE FORECAST TO BE OVER 2000 J/KG ACROSS THE EASTERN CWA
DECREASING RAPIDLY ACROSS THE WEST...AND WE ARE OUTLOOKED FOR A
SLIGHT RISK ACROSS THE ENTIRE AREA TOMORROW. QPF...RAINFALL... WILL
BE GREATEST JUST EAST OF THE CWA.  THE NAM HAS A MUCH BROADER AREA
OF PRECIPITATION COVERING MUCH OF THE STATE BUT THE GREATER 1-2 INCH
BULLSEYE IS LOCATED ACROSS EASTERN NEBRASKA.  GIVEN THE MID LEVEL
INSTABILITY AND THE SURFACE CONDITIONS DURING THE DAY IT IS
DIFFICULT TO PINPOINT THE CONVECTION AND TIMING SO PLACED POPS
THROUGHOUT THE DAY AND INTO THE OVERNIGHT. MOISTURE AND CAPPING WILL
BE A BIT OF A LIMITING FACTOR AS TEMPERATURES WARM BACK INTO THE
90S.  SO GENERALLY SPREAD OUT THE POPS OVER SATURDAY AND SATURDAY
NIGHT BUT KEEP THEM ON THE LOW SIDE.

SUNDAY...MONDAY...MUCH ANTICIPATED DRY WEATHER BEHIND THE
FRONT...CLOUD COVER AND THEN COOLER TEMPERATURES AS THE UPPER RIDGE
BREAKS DOWN FOR OUR AREA AND BUILDS TO THE WEST.  TEMPERATURES WILL
RANGE IN THE MID 80S.  TUESDAY TEMPERATURES BEGIN TO WARM A BIT AS
RIDGING AGAIN MOVES OVER THE AREA.

EXTENDED MODELS DIVERGE BY WEDNESDAY.  BOTH THE EUROPEAN AND THE GFS
SHOW THE UPPER LEVEL RIDGE AXIS ROUGHLY OVER NEBRASKA BUT THE
EUROPEAN BRINGS A PLUME OF MOISTURE UP ALONG THE FRONT RANGE AND
PUSHES IT OUT ACROSS NEBRASKA.  THE GFS SHOWS A SIMILAR ARE OF
CONVECTION BUT DOES NOT BRING ANYTHING OUT INTO THE PLAINS.  THERE
WILL BE MORE TIME TO INTRODUCE POPS AT A LATER TIME...FOR NOW KEPT
THE FORECAST DRY.

&&

.AVIATION...

VFR CONDITIONS EXPECTED THE NEXT 24 HOURS. A TROUGH WILL STALL
ACROSS AREA TONIGHT WITH GENERALLY LIGHT WINDS...LESS THAN
10KTS...OVERNIGHT AND INTO THE DAY TOMORROW. COLD FRONT WILL MARCH
ACROSS THE AREA TOMORROW AND BRING NORTHWEST WINDS. ALONG THE FRONT
WILL ALSO BE A CHANCE FOR THUNDERSTORMS LATER IN THE DAY TOMORROW.

&&

.HYDROLOGY...

 THE SOUTH PLATTE RIVER ITS WAY DOWN AT ROSCOE AND NORTH PLATTE.
ROSCOE HAS DROPPED BELOW FLOOD STAGE SO THE WARNING HAS BEEN
CANCELLED. THE PLATTE RIVER NEAR BRADY CONTINUES TO BE SLIGHTLY
ABOVE FLOOD STAGE...HOWEVER IT IS ALSO DROPPING...AND WILL LIKELY
BE CANCELLED TOMORROW.

THE NORTH PLATTE RIVER UPSTREAM OF LAKE MCCONAUGHY CONTINUES TO BE
ELEVATED. THE LEWELLEN STAGE IS AT A RECORD LEVEL...8.4 FEET
BREAKING THE OLD RECORD OF 8.3 FEET SET IN JUNE OF 1997. THE RIVER
WILL CONTINUE TO BE HIGH INTO NEXT WEEK AS RELEASES CONTINUE FROM
WYOMING RESERVOIRS.

&&

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

&&

DISCUSSION...HIRSCH
AVIATION/HYDRO...MASEK

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
524 PM CDT FRI JUN 25 2010

NEZ004>010-022>029-035>038-056>059-069>071-094-262230-
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-
524 PM CDT FRI JUN 25 2010 /424 PM MDT FRI JUN 25 2010/

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

.DAY ONE...TONIGHT.

THUNDERSTORMS WILL EXIST ALONG A SURFACE THROUGH EXTENDING FROM
NEAR BUTTE AND LONG PINE SOUTHWEST TO NEAR MULLEN THIS EVENING.
A FEW OF THE STRONGEST STORMS WILL BE CAPABLE OF BRIEF HEAVY
RAIN...GUSTY WINDS AND HAIL UP TO QUARTER SIZE. ADDITIONAL
THUNDERSTORM MAY CONTINUE OVERNIGHT AS THE TROUGH RETREATS
NORTHWARD...ACROSS NORTHERN NEBRASKA.

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

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER ALL OF
WESTERN AND NORTH CENTRAL NEBRASKA ON SATURDAY INTO SATURDAY
NIGHT AS A COLD FRONT MOVES ACROSS THE AREA. THE PRIMARY THREAT
AREA WILL BE ALONG AND EAST OF HIGHWAY 83 WITH LARGE HAIL AND
DAMAGING WINDS. LOCALLY VERY HEAVY RAINFALL MAY ALSO OCCUR AND
THIS COULD LEAD TO A RISK OF FLASH FLOODING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TONIGHT.

&&

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

KAR