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000
FXUS63 KGID 190417
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
1117 PM CDT TUE JUN 18 2013

.UPDATE...
ISSUED AT 1117 PM CDT TUE JUN 18 2013

WE ARE SEE A COUPLE SHWRS DEVELOPING FROM MCK INTO FURNAS COUNTY
IN ADVANCE OF AN OUTFLOW BOUNDARY HEADING ENE AT 32 KTS FROM THE
TSTMS NEAR GLD.

LAPS MUCAPE RANGES FROM 500-1500 J/KG...WHICH IS SUPPORTED BY THE
00Z LBF SOUNDING. SHEAR IN THE CLOUD-BEARING LAYER IS 15-20 KTS.
WILL CONTINUE TO MONITOR DEVELOPMENT.

SOME MINOR CHANGES HAVE BEEN MADE TO POPS/WX/SKY OVER THE NEXT
3-6 HRS.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 400 PM CDT TUE JUN 18 2013

PRIMARY CHALLENGE DURING THE NEXT 24 HOURS CONTINUES TO BE FICKLE
THUNDERSTORM CHANCES IN THIS FAIRLY WEAKLY FORCED PATTERN. AT
LEAST A MARGINAL...ISOLATED SEVERE THREAT HAS UNFOLDED ACROSS OUR
SOUTH FOR LATE THIS AFTERNOON INTO THIS EVENING. POTENTIAL STORMS
LATE TONIGHT ARE NOT CURRENTLY EXPECTED TO BE SEVERE...BUT ITS
POSSIBLE A SEVERE THREAT COULD AGAIN DEVELOP ON WEDNESDAY ALTHOUGH
THE DETAILS REMAIN UNCLEAR.

20Z OBJECTIVE SURFACE ANALYSIS HIGHLIGHTS A FAIRLY SUBTLE EAST-
WEST WARM FRONT ACROSS OUR NORTH CENTRAL KS COUNTIES. NORTH OF
THIS BOUNDARY...MOST OF THE CWA IS EXPERIENCING EAST-SOUTHEAST
WINDS AROUND 10 MPH WITH SOME HIGHER GUSTS. AS EARLIER
SUSPECTED/FEARED...ENOUGH AFTERNOON INSTABILITY HAS BUILT UP NEAR
THIS BOUNDARY IN A WEAKLY-CAPPED ENVIRONMENT TO FIRE UP SOME
MAINLY DIURNALLY-DRIVEN...ISOLATED STRONG TO SEVERE THUNDERSTORMS
WITHIN OUR NORTH CENTRAL KS COUNTIES...AND ADJACENT BORDERING
NEBRASKA COUNTIES. SPC MESO-ANALYSIS INDICATES THESE STORMS ARE
BUBBLING UP IN AN ENVIRONMENT CHARACTERIZED BY AROUND 1500 J/KG
0-1KM MLCAPE...BUT RATHER WEAK DEEP-LAYER SHEAR OF LESS THAN 20KT.
AS A RESULT...THESE STORMS ARE STARTING OUT RATHER SLOW-MOVING AND
LIKELY CAPABLE OF AT LEAST MARGINALLY SEVERE HAIL TO AROUND
QUARTERS...WET DOWNBURST WINDS TO AROUND 60 MPH AND BRIEF HEAVY
RAINFALL OF 1-2 INCHES. ALOFT...THE LOCAL AREA FINDS ITSELF UNDER
FAIRLY WEAK NORTH-NORTHWEST FLOW...WITH SHORT TERM MODEL DATA AND
WATER VAPOR IMAGERY REVEALING A FAIRLY SUBTLE EMBEDDED SHORTWAVE
TROUGH MIGRATING SOUTHEAST ACROSS NORTH CENTRAL/NORTHWEST KS...AND
PROVIDING AT LEAST LIMITED LARGE-SCALE SUPPORT TO THE ONGOING
CONVECTION. OTHERWISE...THE VAST MAJORITY OF NEBRASKA ZONES IS DRY
LATE THIS AFTERNOON TO THE NORTH OF THE MAIN LOW-LEVEL CONVERGENCE
ZONE...WITH ONLY A SMATTERING OF FAIR WEATHER CUMULUS AND MID
LEVEL CLOUD DEBRIS. TEMP-WISE...LIKE YESTERDAY MOST PLACES ARE ON
TRACK TO END UP SOMEWHERE IN THE LOW-MID 80S.

FOR LATE THIS AFTERNOON INTO TONIGHT...ONCE AGAIN IT GOES WITHOUT
SAYING THAT FORECASTING POP/THUNDERSTORM TRENDS EVEN BEYOND THE
FIRST 3-6 HOURS CONTINUES TO BE TRICKY. IN SHORT...ANTICIPATE THAT
THE ONGOING STRONG-SEVERE ACTIVITY MAINLY IN KS ZONES AND FAR
SOUTHERN NEB COUNTIES IS DIURNALLY-DRIVEN...WITH QPF FIELDS FROM THE RAP
FADING MOST OF THIS OUT BY SUNSET OR SO. LOOKING AT THE BIG
PICTURE ALOFT OVERNIGHT...ANOTHER LOW AMPLITUDE SHORTWAVE TROUGH
WILL GRADUALLY APPROACH FROM THE WEST...WHICH WILL CONTINUE AIDING
HIGH PLAINS CONVECTION WELL TO OUR WEST THIS EVENING. THE LATEST
THINKING IS THAT MOST....IF NOT ALL THIS HIGH PLAINS ACTIVITY WILL
FAIL TO SURVIVE THIS FAR EAST...BUT THAT A DEVELOPING RIBBON OF
THETA-E ADVECTION IN THE 850-700MB LAYER AND ALONG THE EASTERN
EDGE OF AN 850MB LOW LEVEL JET COULD FIRE UP SOME RANDOM...AT
LEAST ISOLATED CONVECTION MAINLY WELL AFTER MIDNIGHT...AND AS A
RESULT HAVE BLANKETED 20 POPS CWA-WIDE AFTER 06Z/1AM.

THE DETAILS OF THE DAYTIME WEDNESDAY PERIOD ARE STILL VERY MUCH IN
QUESTION. ALOFT...THERE IS AT LEAST SOME UPPER SUPPORT IN THE FORM
OF THE AFOREMENTIONED LOW AMPLITUDE WAVE PASSING WEST-EAST ACROSS
NEB/KS...WHILE WELL UPSTREAM A MUCH LARGER/STRONGER TROUGH WILL
KICK NORTHEAST INTO THE NORTHERN ROCKIES. THIS LARGE SCALE TROUGH
WILL INDUCE SURFACE PRESSURE FALLS...AND RAMP UP SOUTH-SOUTHEAST
WINDS SUSTAINED TO 15-25 MPH AND GUSTING 30-35 MPH...HIGHEST IN
THE WEST AND DURING THE AFTERNOON. WHILE CONFIDENCE IS HIGH IN
THESE INCREASED WINDS...CONFIDENCE IN CONVECTIVE DETAILS REMAIN
LOW...AS LATEST 4KM WRF-NMM SHOWS AN OVERALL LACK OF WIDESPREAD
ACTIVITY TOMORROW. HOWEVER...WITH CAPE AGAIN BUILDING UP TO AROUND
1500 J/KG AND SLIGHTLY BETTER DEEP LAYER SHEAR AROUND 30-35KT...AT
LEAST A FEW SEVERE STORMS ARE POSSIBLE ESPECIALLY FROM LATE
MORNING ONWARD PER SPC SREF SEVERE PROBS. WITH LACK OF A SURFACE
FOCUS HOWEVER...WILL ONLY ADVERTISE 20-30 POPS FOR NOW...WITH THE
EXPECTATION THAT MOST OF THE CWA WILL REMAIN STORM FREE MOST OF
THE DAY. HOPEFULLY THE NEXT FEW SHIFTS CAN SHED A LITTLE MORE
LIGHT ON THE DETAILS...BUT FOR NOW WILL BLANKET GENERAL SEVERE
POTENTIAL EVERYWHERE IN THE HAZARDOUS WEATHER OUTLOOK.

TEMP-WISE...MADE LITTLE CHANGE TO LOWS TONIGHT/HIGHS
TOMORROW...ALTHOUGH HIGHS TOMORROW COULD OBVIOUSLY BE INFLUENCED
BY CONVECTIVE ACTIVITY/CLOUD DEBRIS. FOR NOW WILL AIM FOR LOWS
MAINLY MID 60S AND HIGHS SIMILAR TO TODAY MID TO POSSIBLY UPPER
80S MOST AREAS.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 400 PM CDT TUE JUN 18 2013

PRIMARY FORECAST CONCERNS THROUGH THE LONG TERM PERIOD LIES WITH
PERIODIC THUNDERSTORM CHANCES AND TEMPERATURES.

THUNDERSTORMS CHANCES REMAIN IN PLACE RIGHT OFF THE BAT ACROSS THE
ENTIRE CWA WEDNESDAY EVENING/OVERNIGHT. MODELS IN PRETTY GOOD
AGREEMENT WITH THE UPPER LEVEL PATTERN ACROSS THE CONUS...WITH
CONTINUED ZONAL FLOW THANKS TO WEAK/BROAD RIDGING IN PLACE OVER THE
PLAINS...BETWEEN A EVEN WEAKER TROUGH OVER THE ERN CONUS AND A
STRONGER LOW PRESSURE SYSTEM SET UP OVER THE PAC NW.  OUT AHEAD OF
THE MAIN LOW...EXPECTING A WEAKER SHORTWAVE DISTURBANCE TO BE EJECTED
OUT THROUGH THE ROCKIES AND ONTO THE PLAINS...WITH THUNDERSTORMS ON
GOING BY THE START OF THE PERIOD.  QUESTIONS REMAIN WITH THE OVERALL
COVERAGE OF THE ACTIVITY...AND ITS EVOLUTION OVERNIGHT AS THE
DISTURBANCE SHIFTS EAST...WHICH LOOKS TO PRIMARILY FOCUS ALONG THE
EDGE OF A DEVELOPING 40-50KT LLJ NOSING IN FROM THE SOUTH AND ALONG
THE EDGE OF THE WARMER MID LEVEL TEMPS/CAPPING. THIS KEEPS THE
BETTER CHANCES OVERNIGHT OVER MAINLY ERN PORTIONS OF THE CWA...AND
KEPT HIGHER POPS FOCUSED THERE.  HOWEVER...THERE STILL REMAINS QUITE
A BIT OF VARIABILITY BETWEEN MODELS WITH WHERE THAT BETTER FOCUS
WILL SET UP...WITH SOME KEEPING IT FURTHER NORTH AND/OR EAST THAN
OTHERS. STILL A CONCERN FOR SOME STRONG/SEVERE THUNDERSTORMS...WITH
SUFFICIENT SHEAR/INSTABILITY EXPECTED TO BE IN PLACE.

DURING THE OVERNIGHT HOURS AND INTO THURSDAY...STILL LOOKING AT SOME
AMPLIFICATION OF THE UPPER LEVEL RIDGE THROUGH THE PLAINS...AS THAT
PAC NW LOW MOVES VERY LITTLE.  KEPT THE FORECAST FOR THURSDAY AND
INTO THURSDAY NIGHT DRY...WITH NOT MUCH IN THE WAY OF FORCING AND
INCREASING MID LEVEL TEMPERATURES BRINGING A STRONGER CAP TO
OVERCOME.

INTO FRIDAY THROUGH SUNDAY...MORE SOUTHWESTERLY FLOW LOOKS TO SET UP
IN THE UPPER LEVELS...AS THAT PAC NW LOW PRESSURE SYSTEM FINALLY
STARTS TO MAKE MORE OF AN EASTWARD PUSH INTO THE NRN ROCKIES.  WILL
AGAIN BE CONCERNED ABOUT ANY DISTURBANCES EJECTED OUT AHEAD OF THE
MAIN LOW...BUT WILL CONTINUE TO SEE HEFTY MID LEVEL
TEMPERATURES/CAPPING TO OVERCOME.  DIDNT MAKE ANY SIGNIFICANT
CHANGES TO THE FORECAST FOR THESE DAYS...KEEPING THE INHERITED
SLIGHT CHANCE POPS ACROSS THE FAR SWRN PORTION OF THE CWA.  DURING
THE AFTERNOON HOURS...STEEPER LAPSE RATES ARE EXPECTED TO DEVELOP
AND NOSE INTO THAT AREA...AND ALONG WITH BEING IN CLOSER PROXIMITY
TO A SFC DRYLINE BOUNDARY AND ANY DISTURBANCE MOVING...MIGHT BE
ENOUGH TO SPARK OFF A FEW STORMS LATE EACH AFTERNOON.  SATURDAY
NIGHT STILL LOOKING TO POTENTIALLY SEE THE STRONGER DISTURBANCE OUT
OF THESE DAYS...MAINLY AFFECTING THE NORTHERN HALF OF THE CWA.

UNCERTAINTY IN THE FORECAST...ESP THE PRECIP SIDE OF IT...CONTINUES
RIGHT ON INTO EARLY NEXT WEEK.  AT THIS POINT KEPT THE FORECAST
DRY...WITH BOTH THE GFS/ECMWF SHOWING RIDGING TRYING TO BUILD BACK
NORTH...BUT TO DIFFERING DEGREES. WILL WAIT TO SEE HOW THINGS TREND
BEFORE INSERTING ANY MENTION.

AS FAR AS TEMPERATURES GO...STILL LOOKING AT A WARMING TREND INTO
THE MID/UPPER 90S BY FRIDAY...WITH NEAR 90 TO MID/UPPER 90S THROUGH
EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 639 PM CDT TUE JUN 18 2013

VFR CONDITIONS TO CONTINUE THROUGH THE NEXT 24 HOURS.

A FEW CLOUDS NEAR 5000FT AGL WILL BE POSSIBLE THROUGH MUCH OF THE
TAF PERIOD...WITH A SCATTERED DECK NEAR 25000FT AGL POSSIBLE
DURING THE DAY WEDNESDAY. THE SURFACE WIND WILL REMAIN FROM THE
SOUTHEAST DURING THE TAF PERIOD...SUSTAINED AT AROUND 08KTS
TONIGHT...BUT INCREASING TO AROUND 16KTS AND GUSTING AROUND 25KTS
DURING THE DAY SATURDAY. THERE IS A LOW CHANCE FOR SHOWER AND
THUNDERSTORM ACTIVITY AT THE TERMINAL 06Z ONWARD...BUT AT THIS
TIME THE PROBABILITY OF SUCH CONDITIONS BEING REALIZED AT KGRI IS
TOO LOW FOR INSERTION INTO THE TAF AT THIS TIME. VISIBILITY
RESTRICTION IS NOT EXPECTED AT KGRI THROUGH THE NEXT 24 HOURS.


&&

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

$$

UPDATE...HALBLAUB
SHORT TERM...PFANNKUCH
LONG TERM...ADO
AVIATION...BRYANT