Severe Thunderstorm Warning 258, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
320 AM CDT THU JUL 16 2009

.DISCUSSION...
CONVECTION BLOSSOMING THIS MORNING ACROSS SOUTHWEST NEB...NOT
EXACTLY WHERE ANY GUIDANCE SHOWING IT BUT WATER VAPOR AND
SPECIFICALLY UPSTREAM PROFILERS HINT AT WEAK DISTURBANCE DROPPING
THROUGH WY/CO ROCKIES. A FEW STORMS SHOWING SOME INITIATIVE AND
COULD BE PUTIING DOWN 3/4 INCH HAIL. MUCAPE AND DECENT SHEAR MOST
FAVORABLE ACROSS W.NEB WHERE ASCENT IS BEING AIDED BY LLVL JET WHICH
SHOULD VEER THROUGH NEXT FEW HOURS AND SPREAD CONVECTION INTO
CENTRAL NEB. FARTHER NORTH LAST FEW DAYS OF GUIDANCE COMING TO
FRUITION WITH FAIRLY STRONG LINE OF CONVECTION FROM FAR NORTHEAST
CWA INTO BLACK HILLS IS TRENDING ESE. BUFKIT CONTINUES TO HINT AT
SUPERCELL POSSIBILITIES AND FEW STORMS ACROSS SDAKT INTENSIFYING AS
THEY DROP SOUTHWARD AS WELL. HAVE PLACED HIGHEST POPS IN EASTERN
HALF OF CWA FOR THIS MORNING. PCPN/CLOUDS SHOULD HAMPER TEMPS TODAY
AND KEPT TREND OF COOLER TEMPS IN EASTERN CWA. WITH HIGH BUILDING IN
ACROSS UPPER MS VALLEY INCREASING UPSLOPE INTO HIGHER TERRAIN TO
WEST EXPECT BEST CHANCES THROUGH EVENING WILL BE WEST OF CWA AND
MOST LIKELY WILL NOT SURVIVE PAST SUNSET WITH NOT LLVL JET SUPPORT.
NAM STILL HINTING AT POSSIBILITY OF EARLY MORNING CONVECTION IN FAR
WEST WITH UPPER JET MAXIMA MOVING THROUGH NW FLOW AND WEAK WAVE
INTERACTION WITH BOUNDARY ALONG HIGH PLAINS. HAVE PUT 14 POPS IN FOR
NOW WITH CONFIDENCE STILL NOT HIGH ENOUGH THIS WILL BE IN LBF CWA.
BETTER CHANCES LOOK TO BE FRIDAY AFTERNOON EVENING IN THE WEST WHEN
STRONGER JET ROTATES THROUGH AGAIN AND THETA E RIDGE ALONG HIGH
PLAINS LIGHTS UP. HAVE INCREASED POPS ATTM IN THE SOUTHWEST AND
SHEAR IS DECENT ENOUGH THAT ROTATING STORMS COULD DEVELOP. COOL
CONDITIONS LOOK TO PERSIST IN THIS PATTERN UNTIL MONDAY WHEN NEXT
STRONG NORTHERN STREAM SYSTEM DROPS INTO CANDIAN PRAIRIES AND
SQUEEZES UPPER RIDGE ACROSS PLAINS AGAINST GREAT LAKES LOW.
INSTABILITY WILL PUSH OFF HIGHER TERRAIN INTO CENTRAL NEBRAKA FOR
BETTER PCPN CHANCES INTO EARLY NEXT WEEK.

&&

.AVIATION...
SCATTERED TSTMS ONGOING ACROSS SWRN NEBR. A BRIEF TSTM MAY AFFECT
KLBF IN THE NEXT FEW HOURS...WITH THE POTENTIAL PERSISTING INTO THIS
AFTERNOON. MAY NEED TO UPDATE KLBF TAF AND WILL MONITOR. SCATTERED
TSTMS ACROSS SRN SD MAY DROP INTO KVTN AFT 10Z. CURRENT TAF HAS
TEMPO FROM 11-13Z FOR THIS. PREVAILING WINDS FOR BOTH TAF SITES
SHOULD BE NORTHEAST AOB 10KTS...ALTHOUGH VARIABLE...ESPECIALLY NEAR
TSRA.

&&

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

&&

13/KAR

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
320 PM CDT WED JUL 15 2009

NEZ004>010-022>029-035>038-056>059-069>071-094-161000-
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-
320 PM CDT WED JUL 15 2009 /220 PM MDT WED JUL 15 2009/

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

.DAY ONE...TONIGHT.

ISOLATED THUNDERSTORM DEVELOPMENT IS POSSIBLE IN THE WEST THIS
EVENING...THEN A BETTER CHANCE FOR THUNDERSTORM DEVELOPMENT
OVERNIGHT ACROSS CENTRAL NEBRASKA. TONIGHT AS THE LOW LEVEL JET
INCREASES AS A WEAK COLD FRONT DROPS SOUTHEAST INTO NORTH CENTRAL
NEBRASKA...WHERE SCATTERED COVERAGE OF THUNDERSTORMS IS EXPECTED. A FEW OF
THE STRONGER STORMS MAY CONTAIN BRIEF HEAVY RAIN...GUSTY WINDS AND
SMALL HAIL.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

THUNDERSTORMS ARE EXPECTED TO LINGER THURSDAY AS THE COLD FRONT
ADVANCES INTO KANSAS. THUNDERSTORM CHANCES WILL AGAIN INCREASE
SUNDAY THROUGH TUESDAY AS SOUTHERLY WINDS TRANSPORT MOISTURE FROM
THE GULF OF MEXICO INTO THE OUTLOOK AREA. STRONG AFTERNOON HEATING
WILL CAUSE THUNDERSTORMS TO DEVELOP ACROSS THE HIGHER TERRAIN OF
WYOMING AND SOUTHWEST SOUTH DAKOTA WHICH WILL BE FAVORED TO TRACK
SOUTHEAST ACROSS WESTERN AND NORTH CENTRAL NEBRASKA MAINLY DURING
THE OVERNIGHT HOURS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED THROUGH TONIGHT.

&&

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

KECK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
332 AM CDT THU JUL 16 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0325 AM     HAIL             GRANT                   40.84N 101.73W
07/16/2009  E1.25 INCH       PERKINS            NE   TRAINED SPOTTER

&&

13

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
345 AM CDT THU JUL 16 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0320 AM     HAIL             2 S GRANT               40.82N 101.73W
07/16/2009  E1.75 INCH       PERKINS            NE   TRAINED SPOTTER

&&

KAR

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
407 AM CDT THU JUL 16 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0405 AM     HAIL             3 S ELSIE               40.80N 101.39W
07/16/2009  E1.00 INCH       PERKINS            NE   LAW ENFORCEMENT

            QUARTER SIZE HAIL REPORTED BY THE PERKINS COUNTY
            SHERIFF/S OFFICE.

&&

CJS