Severe Thunderstorm Warning 17, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
254 AM CDT SUN MAY 26 2002

...FORECAST CHALLENGE WILL BE POPS...

LEESIDE TROUGH LOCATED ALONG THE FRONT RANGE AT 06Z WITH HIGH
PRESSURE RIDGING SOUTHWEST ACROSS THE SOUTHERN PLAINS. MOISTURE
CHANNELING NORTH ON THE HIGH PLAINS WITH TWO BOUNDARIES TO BE THE
FOCUS FOR POTENTIAL THUNDERSTORM DEVELOPMENT THROUGH TUESDAY.
SURFACE DEWPOINTS INTO THE 40S EAST OF THE PANHANDLE WITH THE IML
SENSOR AN OUTLIER. WATER VAPOR IMAGERY SHOWS PLENTY OF MID LEVEL
MOISTURE INCOMING ONLY LACKING FACTOR WILL BE THE H3 JET WHICH
REMAINS TO OUR NORTH THROUGH THE PERIOD.

MODELS CONTINUE TO TREND SOUTH AND SLOW THE PROGRESSION THROUGH
96 HOURS. MAIN THREAD WILL BE POSITION OF WEAK FRONTAL BOUNDARY AND
DRYLINE POSITION THAT WILL PROVIDE THE FOCUS FOR ISOLATED TO WIDELY
SCATTERED THUNDERSTORMS THIS AFTERNOON AND CONTINUE THROUGH MONDAY.
BLEND OF MODELS USED WITH WARMER GUIDANCE NUMBERS USED.

THIS AFTERNOON A WEAK FRONTAL BOUNDARY WILL MOVE SOUTH ACROSS
NORTHERN NEB WITH DRYLINE TO EXTEND SOUTH THROUGH THE SOUTHWEST.
PLENTY OF SUNSHINE WILL HELP TO DESTABILIZE THE ATMOSPHERE WITH
MOISTURE LIMITED. WHAT MOISTURE IS AVAILABLE MAY BE SUFFICIENT FOR
ISOLATED STORMS ALONG AND EAST OF THE DRYLINE AS H7 WAVE MOVE EAST
DURING THE AFTERNOON. THEN WIDELY SCATTERED THUNDERSTORMS POSSIBLE
ALONG THE FRONTAL BOUNDARY. MODEL CURRENTLY UNDERCUTTING DEWPOINTS
WITH READINGS PROGGED INTO THE MID 50S THIS AFTERNOON THROUGH THE
NORTH CENTRAL. THE DEGREE OF INSTABILITY WITH BOUNDARIES IN PLACE
WITH INCLUDE LOW POPS THROUGHOUT FORECAST AREA FOR LATE THIS
AFTERNOON.

IN THE EVENING THE DRYLINE WILL PUSH EAST WITH CONVECTION ENDING
AFTER 10 PM ACROSS THE SOUTHWEST. MOISTURE GETS WRAPPED BACK ACROSS
THE NORTH OF THE FRONTAL BOUNDARY WITH A CHANCE OF WIDELY SCATTERED
THUNDERSTORMS CONTINUING OVERNIGHT AS H7 WAVES MOVE EAST. LOWS
TEMPERATURES WILL BE A CHALLENGE AS DRIER AIR FILTERS INTO THE WEST
CENTRAL WITH GUIDANCE NUMBERS UNDERCUT.

MONDAY THE FRONTAL BOUNDARY WILL SINK SOUTHEAST THROUGH THE STATE
WITH THE MAIN FOCUS ACROSS NORTHEAST NEBRASKA AS STRONGER H7 WAVES
MOVES EAST DURING THE EVENING. SERIES OF WAVES ARE PROGGED TO
MOVE EAST OVERNIGHT WITH LOW POPS RETAINED AS TIMING IS IN QUESTION.

TUESDAY A SURFACE TROUGH MOVES IN FROM THE NORTHWEST WITH POTENTIAL
FOR LATE NIGHT CONVECTION TO FORM OVER THE NORTH. THE H7 WAVE MOVES
SOUTHEAST WEDNESDAY MORNING WITH A CHANCE OF SHOWERS AND
THUNDERSTORMS ACROSS THE NORTH CENTRAL. MOISTURE WILL BE LIMITED WITH
LOW POPS INTRODUCED. REMAINDER OF FORECAST AREA WILL BE DRY.

BEYOND THE UPPER RIDGE TAKES HOLD WITH ABOVE NORMAL TEMPERATURES
AND DRY WEATHER INTO THE EXTENDED.

.LBF...NONE.

KECK

NEZ004>010-022>029-035>038-056>059-069>071-094-262045-

HAZARDOUS WEATHER OUTLOOK FOR WESTERN AND NORTH CENTRAL NEBRASKA
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1134 AM CDT SUN MAY 26 2002

...STORM SPOTTERS ACTIVATION MAY BE REQUIRED THIS AFTERNOON AND
EVENING ACROSS SOUTHWEST AND NORTH CENTRAL PORTIONS OF THE OUTLOOK
AREA...

THERE IS A CHANCE OF SEVERE THUNDERSTORMS THIS AFTERNOON AND THIS
EVENING OVER PORTIONS OF WESTERN AND NORTH CENTRAL NEBRASKA. THE
GREATEST RISK OF SEVERE WEATHER WILL BE EAST OF A HAYES CENTER
TO HALSEY TO SPRINGVIEW LINE. OTHER THUNDERSTORMS...WHICH ARE NOT
EXPECTED TO REACH SEVERE LEVELS...ARE POSSIBLE OVER THE REMAINDER OF
THE OUTLOOK AREA.

A NEARLY STATIONARY FRONT LOCATED ACROSS NORTHERN AND EASTERN
PORTIONS OF THE OUTLOOK AREA WILL BE THE FOCUS FOR POSSIBLE SEVERE
THUNDERSTORM DEVELOPMENT THIS AFTERNOON AND EVENING. AS A DISTURBANCE
IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE ENTERS THE OUTLOOK AREA
THIS AFTERNOON...THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE
FRONTAL BOUNDARY. IN ADDITION AS TEMPERATURES RISE AND MOISTURE
BEGINS TO POOL ALONG AND EAST OF THE FRONTAL BOUNDARY...THE
ATMOSPHERE WILL BECOME INCREASINGLY UNSTABLE. ANY THUNDERSTORMS WHICH
DEVELOP EAST OF THE LINE MENTIONED ABOVE WILL HAVE THE POTENTIAL TO
QUICKLY BECOME SEVERE. THE PRIMARY SEVERE WEATHER THREATS WILL BE
LARGE HAIL AND DAMAGING WIND GUSTS OVER 60 MPH.

THE ATMOSPHERE WILL BECOME MODERATELY UNSTABLE THROUGH THE
AFTERNOON AND EVENING HOURS ON MEMORIAL DAY. SEVERE WEATHER WILL BE
POSSIBLE ACROSS PORTIONS OF THE OUTLOOK AREA AND STORM SPOTTER
ACTIVATION MAY BE REQUIRED.