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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
540 AM CDT MON AUG 3 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 357 AM CDT MON AUG 3 2015

A WEAK FRONTAL BOUNDARY REMAINS DRAPED ACROSS THE LOCAL FORECAST 
AREA THIS MORNING AND WILL LIKELY RESULT IN A FAIRLY SHARP 
TEMPERATURE GRADIENT ACROSS THE CENTRAL PLAINS THIS AFTERNOON. TO 
THE EAST AND NORTHEAST OF THIS FRONT...EXPECT HIGH TEMPERATURES
TO ONLY CLIMB INTO THE MID TO UPPER 80S IN SPOTS...WITH
TEMPERATURES REACHING THE MID TO UPPER 90S SOUTHWEST OF THIS
FRONT...PRIMARILY ACROSS PORTIONS OF NORTH CENTRAL KANSAS.

FOR THIS MORNING...MODELS ARE INDICATING WE COULD SEE SOME 
CONVECTIVE DEVELOPMENT ACROSS NORTHEASTERN NEBRASKA AND POTENTIALLY 
CLIPPING THE NORTHEASTERN QUADRANT OF THE LOCAL FORECAST AREA THROUGH 
THE AFTERNOON HOURS...ALTHOUGH SHORT TERM MODEL GUIDANCE HAS BACKED 
OFF ON THIS SCENARIO SOME THE PAST FEW HOURS. EVEN SO...FELT 
JUSTIFIED TO INCLUDE A SMALL CHANCE FOR A THUNDERSTORM ACROSS THIS 
AREA DURING THE FIRST HALF OF THE DAY AS THE AFOREMENTIONED FRONTAL 
BOUNDARY COULD BECOME THE FOCUS FOR SOME MAINLY ISOLATED 
THUNDERSTORM DEVELOPMENT LATER THIS MORNING/AFTERNOON. THEREAFTER... 
EXPECT SOME CONVECTION ROLLING OFF THE HIGH PLAINS TO INTERACT WITH 
THE MEANDERING FRONTAL BOUNDARY...ALSO JUSTIFYING SMALL CHANCES FOR 
SHOWERS AND THUNDERSTORMS DURING THE EVENING AND OVERNIGHT HOURS.

OVERALL...EXPECT SMALL CHANCES FOR CONVECTION THROUGH THE SHORT TERM 
PORTION OF THE FORECAST...WITH SOME POTENTIAL FOR A STRONG TO 
MARGINALLY SEVERE THUNDERSTORM AS PLENTY OF INSTABILITY IS EVIDENT 
IN MODEL SOUNDINGS ALONG WITH MODEST 0-6KM SHEAR VALUES. TEMPERATURE 
WISE...NEAR AND NORTH OF THE COLD FRONT EXPECT SEASONABLY COOL 
READINGS THIS AFTERNOON...WITH SEASONABLY WARM TEMPERATURES EXPECTED 
SOUTH AND WEST OF THIS FRONT LATER TODAY. FOR TONIGHT...WITH SOME 
CLOUD COVER AND SHOWERS AROUND...LIKELY WILL SEE OVERNIGHT LOW 
TEMPERATURES A FEW DEGREES ABOVE THIS MORNINGS VALUES. 

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 357 AM CDT MON AUG 3 2015

PRIMARY FORECAST CONCERN IN THE LONG TERM CONTINUES TO REVOLVE 
AROUND THUNDERSTORM CHANCES. 

MODELS AT THE THE START OF THE PERIOD TUESDAY MORNING SHOW AN AREA 
OF LOW PRESSURE IN THE MID/UPPER LEVELS LOCATED OVER CENTRAL/ERN 
PORTIONS OF WY...RIDING AROUND THE EDGE OF HIGH PRESSURE CENTERED 
OVER THE CA/AZ/MEX BORDER AREA...WHILE A LEAD SHORTWAVE DISTURBANCE 
LOOKS TO BE SLIDING EAST THROUGH PORTIONS OF THE CENTRAL PLAINS. 
CHANCE THAT PRECIP COULD BE ONGOING TUESDAY MORNING...MAINLY 
ACROSS THE NORTHEAST /ASSOCIATED WITH AN AREA OF INCREASED MID LEVEL 
ISENTROPIC LIFT/ AND SW /CLOSER TO THE BETTER LIFT OF THE SHORTWAVE 
DISTURBANCE AND CONVERGENCE ALONG THE NOSE OF THE LLJ/ FRINGES OF 
THE CWA. THROUGH THE MIDDLE SECTION OF THE CWA...MAY NOT BE MUCH 
GOING ON. WEATHER THROUGH THE DAYTIME HOURS TUESDAY AND INTO TUESDAY 
NIGHT WILL BE DRIVEN PRIMARILY BY THAT LOW PRESSURE SYSTEM STARTING 
THE DAY OVER WY. MODELS VARY SOME WITH THE PATH/EVOLUTION OF THE 
LOW...WITH THE ECMWF SLIDING IT EAST CLOSER TO THE NEB/KS STATE LINE 
WITH TIME...VS THE GFS WHICH KEEPS IT FURTHER NORTH CLOSER THE 
NEB/SD STATE LINE. MOST OTHER MODELS ARE TRENDED TOWARD THE ECMWF. 
HARD TO HAVE MUCH CONFIDENCE IN THE PLACEMENT OF ANY SFC 
FEATURES...AS ACTIVITY FROM THE PREVIOUS NIGHT INTO TUES MORNING 
COULD PLAY A ROLE IN WHERE THINGS END UP. DID BUMP UP POPS INTO THE 
40-50 PERCENT RANGE FOR THE AFTERNOON/EVENING HOUR...BUT WITH SOME 
UNCERTAINTIES REMAINING WITH HOW THE OVERALL COVERAGE OF 
THUNDERSTORMS WILL PLAY OUT...DIDNT GO WITH LIKELY POPS...BUT SOME 
UPWARD ADJUSTMENT FOR AT LEAST A PORTION OF THE AREA MAY END UP 
BEING NEEDED...WILL SEE HOW UPCOMING RUNS OF MODELS TREND. STILL A 
CONCERN FOR STRONG/SEVERE THUNDERSTORMS...AND THE ENTIRE CWA REMAINS 
IN THE MARGINAL RISK AREA FROM THE SPC OUTLOOK FOR TUES/TUES NIGHT. 
WILL BE THE POTENTIAL FOR AT LEAST MODEST AMOUNTS OF INSTABILITY TO 
DEVELOP...BUT MODELS DO VARY A BIT ON THE MAGNITUDE OF DEEPER LAYER 
SHEAR...MOST ARE NOT OVERLY IMPRESSIVE...ANYWHERE IN THE 15 TO 35 KT 
RANGE. 

AS WE GET INTO WED/WED NIGHT...THINKING THAT THE 20-30 POPS IN THE 
FORECAST WILL BE PRIMARILY CONFINED TO THE FIRST HALF OF THE DAY 
FROM ANY LINGERING ACTIVITY FROM TUES NIGHT. MODELS SHOWING AT 12Z 
WEDNESDAY THAT AREA OF UPPER LEVEL HIGH PRESSURE HAS BUILT A BIT 
FURTHER NORTH...AND LOOKS TO BE CENTERED NEAR THE AZ/NM BORDER. MAY 
HAVE SOME SHORTWAVE RIDGING BUILDING INTO WRN PORTIONS OF THE 
REGION...BUT ADDITIONAL PIECES OF ENERGY KEEP IT FROM AMPLIFYING 
MUCH. THOUGHT ABOUT PULLING POPS COMPLETELY FROM THE FORECAST FOR 
THE 00-12Z THURSDAY PERIOD...AS SOME MODELS SHOW THINGS QUIET...BUT 
NOT ALL...WITH A FEW STILL SHOWING THE POTENTIAL FOR YET ANOTHER 
WEAK DISTURBANCE PERHAPS BRINGING SOME ISO/SCT PRECIP...SO KEPT THE 
20 POPS GOING.

MORE MODEL DIFFERENCES ARISE AS WE GET INTO THURS/THURS NIGHT. 
GENERALLY ZONAL FLOW IS EXPECTED TO BE IN PLACE THURS MORNING...WITH 
LITTLE CHANGE IN THE PLACEMENT OF THAT SWRN CONUS HIGH...WHILE 
ANOTHER DISTURBANCE LOOKS TO START MOVING THROUGH THE ID/MT/CAN 
BORDER AREA. AT THIS POINT THINKING THAT A GOOD CHUNK/IF NOT MOST OF 
THE DAY WILL BE DRY...BUT UNCERTAINTY IN THE LATER DAYTIME HOURS 
INTO THURS NIGHT LIES WITH IF/WHEN A PIECE OF SHORTWAVE ENERGY OUT 
AHEAD OF THE SYSTEM IN THE NRN ROCKIES SPARKS OFF ANOTHER ROUND OF 
THUNDERSTORMS. SOME OF IT WILL DEPEND ON THE PLACEMENT OF MID LEVEL 
WARMER TEMPS...WHICH THE GFS HAS PUSHING FURTHER NORTH INTO THE CWA 
THAN THE ECMWF...SO IS LATER AND FURTHER EAST WITH ACTIVITY COMPARED 
TO THE ECMWF...WHICH HAS MORE WIDESPREAD QPF PRIOR TO 00Z FRIDAY. 
HARD TO GO VERY HIGH WITH POPS UNTIL THOSE FEATURES/TIMING CAN BE 
WORKED OUT...AND KEPT THINGS IN THE 20-30 PERCENT RANGE FOR NOW.

DO HAVE A DRY FORECAST GOING FOR FRI/FRIDAY NIGHT...WITH MODELS 
SHOWING THE POTENTIAL FOR THE UPPER LEVEL RIDGE TO AMPLIFY JUST 
ENOUGH TO KEEP BETTER THUNDERSTORM CHANCES OUT OF THE CWA...WILL SEE 
IF UPCOMING MODEL RUNS ACTUALLY KEEP THAT IN PLACE. WHATEVER BREAK 
THERE IS LOOKS TO BE A BRIEF ONE...WITH ANOTHER PIECE OF UPPER LEVEL 
SHORTWAVE ENERGY BREAKING DOWN THE RIDGING AND POTENTIALLY MOVING 
RIGHT THROUGH THE CWA FOR LATE IN THE DAY SAT INTO SAT NIGHT. 

AS FAR AS TEMPS GO THROUGH THE LONG TERM PERIOD...NOT LOOKING AT ANY 
SIGNIFICANT SWINGS EITHER WAY...FORECAST HIGHS REMAINING FOR THE 
MOST PART IN THE 80S...WITH SOME 90S POSSIBLE ACROSS SRN LOCATIONS.

&&

.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 534 AM CDT MON AUG 3 2015

VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD...ALBEIT THERE IS
A SMALL CHANCE FOR A VCTS PRIMARILY NORTHEAST OF KGRI OVER THE
NEXT FEW HOURS AND LINGERING INTO THE AFTERNOON. OTHERWISE...
INCREASING MID-UPPER LEVEL CLOUD COVER IS EXPECTED THROUGH THE DAY
AS THE REMNANTS OF A WEAK FRONTAL BOUNDARY REMAIN DRAPED ACROSS
SOUTH CENTRAL AS WELL AS EASTERN NEBRASKA. WITH THE LOCATION OF
THIS FRONTAL BOUNDARY AND HIGH PRESSURE ACROSS EASTERN SOUTH
DAKOTA...PRIMARILY EASTERLY WINDS CAN BE EXPECTED...MAYBE AS HIGH
AS 12KTS AT TIMES DURING THE AFTERNOON HOURS. LATER THIS AFTERNOON
AND EVENING...ADDITIONAL SHOWERS AND THUNDERSTORMS MAY FIRE UP
NEAR THE AFOREMENTIONED FRONTAL BOUNDARY...AND OPTED TO COVER THIS
WITH A VCTS AS WELL.

&&

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

$$

SHORT TERM...ROSSI
LONG TERM...ADP
AVIATION...ROSSI

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