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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
616 PM CDT TUE JUL 29 2014

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 410 PM CDT TUE JUL 29 2014

THE MAIN ISSUE THROUGH THE NEXT 24 HOURS REVOLVES AROUND HOW MUCH
SHOWER/WEAK THUNDERSTORM POTENTIAL MAINLY THE SOUTHWEST 1/3 TO
POSSIBLY 1/2 OF THE CWA WILL SEE...PRIMARILY LATE TONIGHT THROUGH
MID-DAY ON WEDNESDAY. THE GENERAL EXPECTATION IS THAT ANY PRECIP
AMOUNTS WILL LIKELY AVERAGE WELL UNDER 0.25 INCH IN MOST AREAS
THROUGH THIS TIME...AND EVEN AMOUNTS CLOSE TO THAT MUCH WOULD
PROBABLY FOCUS IN THE EXTREME SOUTHERN/SOUTHWEST CWA...WITH
CONSIDERABLY BETTER RAIN CHANCES FOCUSING AT LEAST SLIGHTLY
OUTSIDE THE LOCAL AREA WITHIN PARTS OF WESTERN NEB AND
WESTERN/SOUTHERN KS. IN CONTRAST...EVEN A BRIEF SPRINKLE WILL BE
HARD TO COME BY THROUGH THE NEXT 24 HOURS FOR ROUGHLY THE
NORTHEAST 1/2 OF THE CWA...AND IN FACT THE OFFICIAL FORECAST HAS
NO MENTION OF RAIN WHATSOEVER IN THESE AREAS. COMPARED TO THE
PREVIOUS FORECAST...THE NORTHEAST EXTENT OF LOW-END POPS HAS BEEN
TRIMMED...ESPECIALLY FOR THE WEDNESDAY DAYTIME HOURS WHICH ARE NOW
LOOKING DRY FOR ALL BUT MAYBE ROUGHLY THE SOUTHERN/SOUTHWEST 1/4
OF THE CWA AND EVEN THEN MAINLY IN THE MORNING. 

STARTING WITH THE HERE AND NOW AS OF 20Z/3PM...IT HAS BEEN DRY-
CWA WIDE FOR SEVERAL HOURS NOW SINCE THE NORTHWEST-SOUTHEAST BAND
OF SPOTTY SHOWERS FADED AWAY BY MID-DAY. THIS AFTERNOON...SKIES
HAVE CLEARED SOMEWHAT TO YIELD COVERAGE RANGING FROM MOSTLY SUNNY
TO PARTLY CLOUDY MOST AREAS. ALOFT IN THE MID-UPPER LEVELS...WATER
VAPOR SATELLITE AND SHORT TERM MODEL DATA INDICATE THE SAME
OVERALL PATTERN THAT WILL REMAIN VERY PERSISTENT THIS WEEK...WITH
NORTHWEST FLOW ALOFT OVER THE LOCAL AREA DIRECTED IN BETWEEN A
BROAD RIDGE WITH SEVERAL EMBEDDED SMALLER DISTURBANCES OVER THE
WESTERN CONUS...AND A MORE PROMINENT BROAD EXPANSIVE EASTERN CONUS
TROUGH ANCHORED BY A CLOSED LOW CENTERED NEAR JAMES BAY IN CANADA.
AT THE SURFACE...THE COMBINATION OF HIGH PRESSURE CENTERED TO THE
EAST-NORTHEAST AND WEAK LOW PRESSURE NEAR THE CO/KS BORDER IS
YIELDING LIGHT/VARIABLE TO SOMEWHAT STEADIER EASTERLY BREEZES
AROUND 10 MPH DEPENDING ON WHICH PORTION OF THE CWA. HIGH TEMPS
ARE ON TRACK TO END UP A TOUCH WARMER THAN ORIGINAL MORNING
FORECAST IN SOME AREAS...BUT WITH MOST OF THE CWA IN THE 78-82
RANGE...AND WARMER HIGHS OF 82-88 IN SOUTHWEST COUNTIES.

LATE THIS AFTERNOON...LEFT OUT ALL MENTION OF PRECIP...EVEN
SPRINKLES THROUGH 00Z/7PM AS ANY FOCUS REMAINS FARTHER WEST. 

THIS EVENING/TONIGHT...GENERALLY DELAYED THE ONSET OF RAIN CHANCES
AND AGAIN TRIMMED THE NORTHEAST EDGES OF BOTH POPS AND THUNDER
POTENTIAL A BIT...WITH ANY ISOLATED THUNDER RELEGATED GENERALLY
SOUTHWEST OF A LEXINGTON-FRANKLIN-BELOIT LINE WHERE AT LEAST
MEAGER ELEVATED INSTABILITY ON THE ORDER OF POTENTIALLY UP TO A
FEW HUNDRED J/KG CAPE PER THE 12Z/18Z NAM. ALTHOUGH NOT EXPECTING
THUNDER FARTHER NORTHEAST...DID AT LEAST ACKNOWLEDGE A SLIGHT
CHANCE OF SPRINKLES AS FAR NORTHEAST AS ROUGHLY A KEARNEY-
HASTINGS-HEBRON LINE...AND MAINLY FOR AFTER MIDNIGHT. MODELS VARY
ON HOW AGGRESSIVE TO GET WITH PRECIP CHANCES TONIGHT...BUT HAVE
OPTED TO PLAY IT CONSERVATIVE WITH ONLY 20-40 POPS. AS FOR
FORCING...THE GENERAL STORY IS THAT A COMBINATION OF WEAK
SHORTWAVE DISTURBANCES DROPPING DOWN FROM THE NORTH AND ALSO
SLIDING MAINLY JUST SOUTHWEST OF THE CWA WILL INDUCE A ZONE OF MID
LEVEL SATURATION/FRONTOGENESIS EVIDENT AROUND 700-600MB...WHICH
COULD PROMOTE THIS MAINLY LIGHT PRECIP. ALTHOUGH CLOUDS COULD HOLD
UP LOWS A BIT HIGHER THAN FORECAST ESPECIALLY SOUTH AND
WEST...HAVE AIMED FOR MID-UPPER 50S IN MOST NEB ZONES AND LOW-MID
60S IN KS.

FOR THE WEDNESDAY DAYTIME HOURS...THE FORCING FROM THE PAIR OF
SHORTWAVE DISTURBANCES MENTIONED ABOVE GRADUALLY DEPARTS THE
AREA...RESULTING IN PREVAILING ISENTROPIC DOWNGLIDE AS EVIDENT ON
THE 310/315K SURFACES. AS A RESULT...WHATEVER RAIN MIGHT BE GOING
ON TO START THE DAY AROUND SUNRISE SHOULD GRADUALLY SINK FARTHER
SOUTHWARD WITH TIME...AND WOULD EXPECT THE ENTIRE CWA TO BE VOID
OF EVEN SPRINKLES BY MID-AFTERNOON ALTHOUGH IT COULD BE A CLOSE
CALL IN THE EXTREME SOUTHWEST. RIGHT AWAY IN THE MORNING...KEPT
SOME LOW 20-30 MEASURABLE POPS GOING IN SOUTHERN/SOUTHWEST ZONES.
ALTHOUGH VERY MEAGER CONVECTIVE INSTABILITY MAY EXIST DURING THE
DAY...SREF THUNDER PROBABILITIES ARE ESSENTIALLY NON-EXISTENT SO
POTENTIALLY ROLLED THE DICE A BIT AND REMOVED ALL MENTION OF
THUNDER FROM THE FORECAST AND WENT SHOWERS/SPRINKLES ONLY. AS FOR
HIGH TEMPS...THEY COULD AGAIN BE TEMPERED A BIT BY PLENTY OF
EARLY-MID DAY CLOUD COVER...BUT ASSUMING AT LEAST MOST OF THE CWA
AVERAGES NO WORSE THAN PARTLY CLOUDY DURING THE AFTERNOON...OPTED
TO BUMP ANOTHER 1-2 DEGREES ONTO PREVIOUS FORECAST. THIS PUTS MOST
OF THE CWA BETWEEN 80-82.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 410 PM CDT TUE JUL 29 2014

MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS TUESDAY AND 
TEMPERATURES THROUGH THE PERIOD. 

NORTHWEST FLOW WILL CONTINUE THROUGH THE PERIOD WITH A RIDGE IN THE 
WESTERN CONUS AND A TROUGH IN THE EAST. WITH THE NORTHWEST FLOW 
THERE ARE SEVERAL UPPER LEVEL WAVES THAT MOVE THROUGH THE AREA. WITH 
EACH OF THE WAVES THERE IS SOME POTENTIAL FOR THERE TO BE SOME 
SHOWERS AND THUNDERSTORMS. 

MODELS HAVE A FEW DIFFERENCES IN STRENGTH OF THE UPPER LEVEL WAVES 
THAT MOVE THROUGH THE AREA DURING THE PERIOD. HAVE KEPT THE FORECAST 
DRY AT THIS TIME FOR WEDNESDAY NIGHT THROUGH SUNDAY NIGHT. THERE ARE 
A FEW FAIRLY WEAK WAVES THAT MOVE THROUGH AND THERE IS A SMALL 
POSSIBILITY THERE COULD BE SOME VERY ISOLATED SHOWERS AND 
THUNDERSTORMS BUT OF THE MODELS ONLY SOME OF THEM HAVE PRECIPITATION 
FOR ANY PART OF THE AREA. THERE WILL BE SOME TIME TO ADD 
PRECIPITATION CHANCES IF SOME OF THE UPPER WAVES HAVE MORE STRENGTH. 
TEMPERATURES DURING THIS TIME WILL BE A LITTLE COOLER THAN NORMAL 
WITH TEMPERATURES WARMING A DEGREE OR TWO EACH DAY. 

MONDAY THROUGH TUESDAY THERE IS A STRONGER WAVE THAT MOVES THROUGH 
THE UPPER RIDGE AND INTO THE REGION. AT THE SAME TIME A SURFACE LOW 
DEVELOPS ON THE HIGH PLAINS. THE UPPER WAVE MOVES INTO THE AREA 
MONDAY AND EXPECT THAT PRECIPITATION WILL START TO MOVE INTO THE 
AREA ON MONDAY AND SPREAD ACROSS THE AREA MONDAY NIGHT INTO TUESDAY 
AS THE UPPER WAVE MOVES THROUGH THE AREA AND THE SURFACE LOW DRIFTS 
TO THE EAST. THERE ARE STILL A FEW DIFFERENCES BETWEEN THE MODELS 
AND THE MODELS ARE PUSHING THE WAVE A LITTLE LATER SO WILL HAVE TO 
KEEP AN EYE ON THIS SYSTEM. 

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 616 PM CDT TUE JUL 29 2014

EXPECT VFR CONDITIONS TO CONTINUE DURING THE FORECAST PERIOD.
WINDS WILL REMAIN LIGHT WITH AN EASTERLY COMPONENT WITH SURFACE
HIGH PRESSURE IN EASTERN NEB AND LOW PRESSURE ALONG THE LEE OF THE
ROCKIES. THIS PATTERN SHOULD HOLD THROUGH NOON WED. JUST A VERY
SMALL CHANCE FOR LIGHT RAIN OVERNIGHT IN THE KEAR AREA...BUT WELL
BELOW 30 PERCENT CRITERIA WITH BETTER CHANCES FURTHER WEST AND
SOUTHWEST.

&&

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

$$

SHORT TERM...PFANNKUCH
LONG TERM...JCB
AVIATION...EWALD

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