Hail and Damaging Winds in Nebraska, June 19 to 20, 2010

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
317 AM CDT SAT JUN 19 2010

.DISCUSSION...THE PRIMARY CONCERN OVER THE NEXT COUPLE OF DAYS WILL
BE THE CHANCE OF SEVERE THUNDERSTORMS.  REGIONAL RADAR MOSAIC EARLY
THIS MORNING SHOWED THUNDERSTORMS MOVING NORTHEAST OUT OF NORTHEAST
COLORADO AND SOUTHWEST NEBRASKA.  EARLY MORNING SURFACE ANALYSIS
PLACED A NEARLY STATIONARY FRONT FROM WEST CENTRAL KANSAS INTO
NORTHERN MISSOURI. THE FRONT WILL BE THE MAIN FOCUS FOR
THUNDERSTORMS OVER THE NEXT COUPLE OF DAYS AS IT CONTINUES TO
MEANDER ACROSS THE CENTRAL PLAINS.

H85 WARM AIR ADVECTION IN COMBINATION WITH THE LOW LEVEL JET WILL
HELP KEEP A CHANCE OF THUNDERSTORMS ACROSS MUCH OF THE FORECAST AREA
THIS MORNING.  THE HIGHER CHANCES SHOULD RESIDE IN THE WEST CLOSER
TO THE NOSE OF THE LOW LEVEL JET AND IN THE REGION OF STRONGER H85
WARM AIR ADVECTION.  THE THUNDERSTORM CHANCES SHOULD DIMINISH LATE
THIS MORNING...THOUGH AM NOT CONFIDENT ENOUGH IN IT BEING DRY TO
COMPLETELY REMOVE POPS DURING THAT PERIOD.

THE FRONTAL BOUNDARY WILL MOVE NORTH TODAY...AND BY MID TO LATE
AFTERNOON SHOULD BE NEAR THE KANSAS AND NEBRASKA BORDER.
INSTABILITY ALONG THE FRONT WILL BE VERY HIGH WITH 0-1KM MLCAPE OF
3000-4000 J/KG.  0-6KM DEEP LAYER SHEAR WILL BE SUFFICIENT FOR
SUPERCELLS...SO ANY STORMS WHICH CAN DEVELOP SHOULD RAPIDLY BECOME
SEVERE.  THE PRIMARY THREATS WILL BE VERY LARGE HAIL AND DAMAGING
WINDS...THOUGH AN ISOLATED TORNADO IS ALSO POSSIBLE WITH SUFFICIENT
0-1KM STORM RELATIVE HELICITY.  PROBABLY THE BIGGEST QUESTION FOR
THIS AFTERNOON/EVENING WILL BE VERY WARM H7 TEMPERATURES.  THE 00Z
GFS SHOWS H7 TEMPERATURES NEAR +15C IN THE SOUTHERN PORTION OF THE
FORECAST AREA...WITH AT LEAST +12C VALUES COVERING ALL BUT THE FAR
NORTHEAST PORTION OF THE CWA.  THIS COULD TEND TO LIMIT THE
CONVECTIVE POTENTIAL IN THE SOUTH AND WEST...AND HAVE KEPT THE
HIGHER POPS OVERALL IN THE NORTH AND EAST.  HEAVY RAINFALL AND
FLOODING WILL BE ANOTHER POTENTIAL THREAT FROM THE STORMS WITH
PRECIPITABLE WATER VALUES NEAR 2 INCHES THIS AFTERNOON/EVENING.

H85 WARM AIR ADVECTION CONTINUES ACROSS SOUTH CENTRAL NEBRASKA MUCH
OF THE NIGHT AS THE LOW LEVEL JET AGAIN PUSHES INTO THE AREA.  THE
BETTER FOCUS ALONG THE NOSE OF THE LOW LEVEL JET AXIS EVENTUALLY
SHIFTS EAST AND NORTH OF THE FORECAST AREA...BUT THERE SHOULD BE A
FAIRLY DECENT CHANCE OF THUNDERSTORMS IN THE NORTH AND EAST PORTION
OF THE CWA UNTIL THAT OCCURS.  A FEW STORMS COULD LINGER INTO SUNDAY
MORNING...BUT THE GENERAL TREND FOR SUNDAY MORNING SHOULD BE FOR
THINGS TO DRY OUT.

THE FRONTAL BOUNDARY WILL REMAIN IN THE REGION AGAIN FOR SUNDAY
AFTERNOON WHICH COULD AGAIN BE THE FOCUS FOR MORE THUNDERSTORMS.
CONFIDENCE IN THE BOUNDARY PLACEMENT BECOMES A BIT LESS ON SUNDAY
SINCE THE CONVECTION FROM TONIGHT WILL LIKELY INFLUENCE THE LOCATION
OF THE BOUNDARY ON SUNDAY.  THAT BEING SAID...THE GENERAL CONSENSUS
AMONGST THE VARIOUS SHORT TERM MODEL SOLUTIONS WOULD PLACE THE
BOUNDARY FROM NORTHWEST KANSAS INTO SOUTHWEST IOWA...WHICH WOULD
GIVE THE HIGHER THUNDERSTORM CHANCES TO PORTIONS OF SOUTH CENTRAL
NEBRASKA FOR SUNDAY AFTERNOON INTO SUNDAY NIGHT.  SOME OF THE STORMS
COULD AGAIN BE SEVERE...AND WILL CONTINUE TO MENTION THAT POSSIBILITY
IN THE HAZARDOUS WEATHER OUTLOOK THIS MORNING. THE FRONT REMAINS
IN THE REGION ON MONDAY WITH ADDITIONAL THUNDERSTORM CHANCES ALONG
WITH THE POSSIBILITY OF SEVERE WEATHER.

&&

.AVIATION...06Z KGRI TAF. WEAK COLD FRONT STRETCHED ACROSS SW TO
NE KANSAS WITH WEAK PRESSURE GRADIENT ACROSS NEBRASKA RESULTING IN
LIGHT AND VARIABLE WINDS. CLEAR SKIES SHOULD PREVAIL FOR MOST OF
THE NIGHT BEFORE HIGH CLOUDS ASSOCIATED WITH TSTMS IN NE COLORADO
DRIFT IN TOWARDS DAWN. STILL SOME QUESTION WHETHER THOSE STORMS
CAN HOLD TOGETHER OVERNIGHT AS THEY DRIFT ENE. FOR NOW WILL LEAVE
TSTM CHANCES OUT OF TAF AND CONTINUE TO MONITOR. OTHERWISE CHANCES
INCREASE FOR TSTMS SAT NIGHT AND WILL INSERT PROB 30 WORDING.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE HASTINGS NE
1006 PM CDT FRI JUN 18 2010

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-
191200-
PHILLIPS-SMITH-JEWELL-ROOKS-OSBORNE-MITCHELL-VALLEY-GREELEY-NANCE-
SHERMAN-HOWARD-MERRICK-POLK-DAWSON-BUFFALO-HALL-HAMILTON-YORK-
GOSPER-PHELPS-KEARNEY-ADAMS-CLAY-FILLMORE-FURNAS-HARLAN-FRANKLIN-
WEBSTER-NUCKOLLS-THAYER-
1006 PM CDT FRI JUN 18 2010

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

.DAY ONE...TONIGHT.

THERE IS AN OUTSIDE CHANCE FOR A THUNDERSTORM OR TWO TOWARD
DAYBREAK.  SEVERE WEATHER IS NOT EXPECTED AT THIS TIME.

RIVER FLOODING WILL CONTINUE ALONG THE PLATTE RIVER NEAR KEARNEY
NEBRASKA INTO EARLY EVENING.

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

THERE ARE INTERMITTENT CHANCES OF THUNDERSTORMS IN THE FORECAST
FROM SATURDAY THROUGH TUESDAY NIGHT. SOME OF THE STORMS LATE
SATURDAY AFTERNOON INTO SATURDAY NIGHT AND AGAIN SUNDAY NIGHT
COULD BE SEVERE WITH THE MAIN HAZARDS EXPECTED TO BE LARGE HAIL
AND DAMAGING WINDS. HEAVY RAIN IS ALSO POSSIBLE ACROSS PORTIONS OF
SOUTH CENTRAL NEBRASKA THIS WEEKEND...WHICH COULD CAUSE ADDITIONAL
FLOODING PROBLEMS.

INTO EARLY NEXT WEEK...WARMER TEMPERATURES ARE EXPECTED ACROSS
NORTH CENTRAL KANSAS AND FAR SOUTHERN NEBRASKA...WITH HEAT INDEX
VALUES OF OVER 100 DEGREES POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT.

&&

MORE INFORMATION MAY BE OBTAINED AT THE FOLLOWING WEB PAGE:
   HTTP://WWW.WEATHER.GOV/HASTINGS  (ALL LOWERCASE)