000
FXUS63 KGID 181411
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
911 AM CDT TUE JUN 18 2013

.UPDATE...
ISSUED AT 910 AM CDT TUE JUN 18 2013

FIRST MID-MORNING UPDATE JUST COMPLETED. IN SHORT...ISOLATED TO
SCATTERED...GENERALLY WEAK CONVECTION CONTINUES TO DRIFT EAST-
SOUTHEAST THROUGH COUNTIES PRIMARILY NEAR THE I-80 AND HIGHWAY 6
CORRIDORS...AND ALSO EXTENDING SOUTHWEST THROUGH THE
HOLDREGE/PHILLIPSBURG AREAS. HAVING MUCH CONFIDENCE IN HOURLY POPS
IN THIS KIND OF SITUATION IS DICEY...BUT HAVE AT LEAST ATTEMPTED TO
HIGHLIGHT THOSE AREAS WITH GREATER THAN A 20 PERCENT CHANCE OF
MEASURABLE RAIN YET THIS MORNING...WHILE LEAVING OUT MORNING POPS
ALTOGETHER FOR FAR NORTHWEST/WEST PLACES SUCH AS
ORD/GREELEY/GOTHENBURG WHO APPEAR TO BE BEHIND THE SUBTLE LOW-MID
LEVEL THETA-E ADVECTION DRIVING THIS ACTIVITY...ALONG THE SOUTHWEST
PERIPHERY OF A MODEST SHORTWAVE TROUGH DIVING SOUTHEAST ACROSS IA.
INHERITED FORECAST IS RAIN/THUNDER-FREE CWA-WIDE BETWEEN 1PM-
10PM...AND AM JUST NOT SURE YET IF THIS IS GOING TO HOLD OR NOT.
DETERMINISTIC MODELS CONTINUE TO STRUGGLE MIGHTILY WITH QPF
FIELDS...AND IF ADDITIONAL SUBTLE MID-LEVEL ENERGY CAN INTERACT
WITH BUILDING LOW-LEVEL INSTABILITY PROGGED TO REACH/EXCEED 1500
J/KG PER THE RAP...THEN COULD SEE MORE HIT-OR-MISS CONVECTION THIS
AFTERNOON...AND THATS ASSUMING THAT THIS MORNINGS ACTIVITY EVEN
COMPLETELY FADES AWAY IN THE FIRST PLACE...WHICH IS DOES SEEM TO
BE DOING NOW. AT LEAST FOR NOW...WILL LEAVE THE AFTERNOON DRY AND
MONITOR SHORT-TERM TRENDS FOR UPDATES. HOWEVER...SHOULD ANYTHING
FIRE UP LOCALLY THIS AFTERNOON WITH THE HEATING OF THE
DAY...CANNOT RULE OUT A STRONG TO MARGINALLY SEVERE STORM. STILL
THOUGH...PRIMARY CORRIDOR OF MORE ORGANIZED AND WIDESPREAD LATE
AFTERNOON/EVENING CONVECTION STILL LOOKS TO FOCUS WELL TO OUR WEST
ACROSS THE NEB PANHANDLE/EASTERN CO/NORTHWEST KS...AND EVENTUALLY
POSSIBLY MAKE A RUN EAST TOWARD US LATER TONIGHT. BOTTOM
LINE...PLEASE BARE WITH US AS THE SHORT-TERM PREDICTABILITY IN
THIS WEAKLY FORCED BUT WEAKLY CAPPED PATTERN IS A CHALLENGE TO SAY
THE LEAST. NO OTHER CHANGES MADE AT THIS TIME.

UPDATE ISSUED AT 619 AM CDT TUE JUN 18 2013

A BEAUTIFUL SUNRISE HERE AT THE OFFICE WITH SUNLIT CU AND MAMMATUS
PEARLS.

THE REMNANTS OF THE MCS ARE PROPAGATING MORE SSE NOW. NEW CELL
DEVELOPMENT IS OCCURRING ATOP AND BEHIND THE OUTFLOW BOUNDARY THAT
CURRENTLY EXTENDS FROM LOUP CITY-KEARNEY TO NEAR HARLAN COUNTY
LAKE. POPS HAVE BEEN UPDATED TO ADJUST FOR THESE SHORT-TERM
TRENDS.

MESONET SITES HAVE INDICATED VERY HEAVY RAINFALL IN SPOTS. AS OF
THIS WRITING:

LEXINGTON 3 NE: 1.86
LEXINGTON: 1.13
SW SIDE OF JOHNSON LAKE: 1.52

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM CDT TUE JUN 18 2013

AN SPS POSTED AT 316 AM FOR TSTMS OVER LINCOLN COUNTY. ONE CELL
BRIEFLY HAD 50 DBZ UP TO 30K FT.

ALOFT: A WRN USA  RIDGE/ERN USA TROF WAS IN PLACE WITH A SLOW-
MOVING CLOSED LOW OFF THE PAC NW COAST. THIS PATTERN WILL BE
MODESTLY PROGRESSIVE OVER THE NEXT 24-30 HRS. BY THIS TIME
TOMORROW MRNG THE RIDGE WILL BE BACK OVER THE PLAINS...WITH THE
PAC NW LOW INLAND OVER OR. IN THE MEANTIME...A WELL-DEFINED VORT
MAX WAS EXITING THE DAKOTAS INTO MN/IA EARLY THIS MRNG.

SFC: HIGH PRES EXTENDED THE LENGTH OF THE PLAINS AND WILL SLOWLY
DRIFT INTO THE GREAT LAKES AND MS VALLEY TODAY-TNGT. WHILE THIS
OCCURS...A COOL FRONT WILL MOVE INTO THE WRN USA.

THIS FCST HEAVILY HINGES ON SHWR/TSTM TRENDS AND/OR DEVELOPMENT.

EARLY THIS MRNG: SHWRS/TSTMS ARE DEVELOPING AS MODELED. IT
APPEARS THERE IS A RISK OF SHWRS AND POSSIBLY A TSTM N AND E OF
THE TRI- CITIES...ASSOCIATED WITH THE VORT MAX MOVING INTO MN/IA.
THE OTHER THREAT IS THE SMALL MCS CURRENTLY MOVING THRU THE LBF
AREA.

TODAY: EXPECT A THREAT OF PCPN TO END BY MIDDAY. THEN WE ARE
PROBABLY DRY THE REST OF THE DAYLGT HRS. DECREASING CLOUDS AND IT
SHOULD BE A NICE AFTN WITH LGT WINDS AND TEMPS A COUPLE DEGS ABOVE
NORMAL.

HIGHS ARE BASED ON THE CANADIAN GEM WITH A BIAS CORRECTION.

TNGT: TSTMS DEVELOP AGAIN OVER THE PANHANDLE/ERN CO. NOT EXACTLY
SURE HOW THEY EVOLVE.  MODELS INDICATE A SHRTWV TROF MOVING THRU
THE RIDGE TNGT...PROVIDING A FAVORABLE LARGE-SCALE ENVIRONMENT
FOR THESE TSTMS TO MOVE E INTO THE FCST AREA. HOWEVER...AM UNSURE
IF THIS IS A REAL SHRTWV TROF OR IF ITS CONVECTIVELY SPURIOUS.
ONE ENCOURAGING FACTOR IS THE 70 KT ULJ STREAK HEADING INTO AZ/NM.
ANOTHER IS THAT A 35-40 KT LLJ IS FCST TO DEVELOP. STAYED TUNED.
HOPEFULLY POPS WILL END UP MUCH HIGHER THAN CURRENTLY IN THE FCST.
MANY PARTS OF THE FCST AREA THAT DIDNT GET RAIN FROM SUN EVNG
STORMS NEED RAIN BADLY.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 413 AM CDT TUE JUN 18 2013

QUICK SUMMARY: HOT WEATHER IS ON THE WAY WITH WEDNESDAY BEING THE
LAST DAY OF LOWER TO MID 80S FOR HIGHS. EXPECT UPPER 80S TO MID 90S
ACROSS THE AREA ON THURSDAY WITH EVERYONE IN THE 90S BY FRIDAY AND
SATURDAY. MAY SEE A SLIGHT COOL DOWN SUNDAY AND MONDAY...BUT HIGHS
SHOULD STILL BE IN THE UPPER 80S TO MID 90S. THE BEST CHANCE FOR
THUNDERSTORMS APPEARS TO BE WEDNESDAY/WEDNESDAY NIGHT AS AN UPPER
VORT MAX MOVES THROUGH. UPPER RIDGING AND WARMING TEMPERATURES ALOFT
THURSDAY THROUGH SATURDAY SHOULD KEEP MOST AREAS DRY...WITH PERHAPS
SOME LOWER END CHANCES OF THUNDERSTORMS BY SATURDAY NIGHT THROUGH
MONDAY.

WEDNESDAY...THE 06Z NAM AND 00Z RUNS OF THE ECMWF AND GFS ALL BRING
A WEAK SHORT WAVE THROUGH THE CENTRAL PLAINS BENEATH AN OVERALL
STRENGTHENING UPPER RIDGE. THIS SHORT WAVE UNDERCUTS THE RIDGE AND
SHOULD PROVIDE ENOUGH FORCING TO WARRANT ONE OF OUR BETTER CHANCES
OF THUNDERSTORMS. INSTABILITY AND 0-6KM SHEAR WILL BOTH BE MODEST
WITH MLCAPE VALUES OF 1500 TO 2000 J/KG...AND DEEP LAYER SHEAR OF 30
TO 40 KTS. GIVEN THE INSTABILITY...SHEAR...AND THAT WE SHOULD
FINALLY ACTUALLY HAVE SOME FORCING WE COULD SEE A FEW SEVERE
THUNDERSTORMS.

THURSDAY THROUGH SATURDAY...TEMPERATURES INCREASE ALOFT ESPECIALLY
AT 700MB...WHICH SHOULD MAKE FOR A STRENGTHENING CAP.
CONSEQUENTLY...MOST AREAS SHOULD BE DRY. THERE MAY BE A WEAK VORT
MAX OR TWO THAT TRACK ACROSS THE AREA...BUT THE CAP WILL BE
DIFFICULT TO OVERCOME. THE ONLY POPS IN THE FORECAST DURING THIS
PERIOD WILL BE ACROSS OUR KANSAS COUNTIES WHERE CONVECTION SOMETIMES
CAN OVERCOME THE CAP ON THE HIGH PLAINS DUE TO SIGNIFICANT HEATING
AND THEN MAY SLIDE INTO OUR AREA. EVEN SO...THIS IS A VERY LOW END
20 PERCENT CHANCE. THIS WILL BE A HOT PERIOD WITH HIGHS GENERALLY IN
THE 90S FOR MOST LOCATIONS FRIDAY AND SATURDAY. A FEW SPOTS MAY
STILL HOLD IN THE UPPER 80S ON THURSDAY.

SATURDAY NIGHT THROUGH MONDAY...THE MAIN UPPER TROUGH OVER THE
NORTHERN ROCKIES WILL SLIDE INTO THE NORTHERN PLAINS. THE BEST
CHANCE OF STORMS WILL BE WELL NORTH OF OUR FORECAST AREA...BUT WE
COULD ONCE AGAIN SEE AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS DUE
TO THE FLATTENING OF THE UPPER RIDGE AND PERHAPS A LITTLE FORCING.
THERE IS STILL A LOT OF UNCERTAINTY WITH THE RAIN CHANCES IN THIS
PERIOD AND AT THIS TIME THERE IS CERTAINLY NO WELL ORGANIZED SYSTEM
ON THE HORIZON FOR US.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 636 AM CDT TUE JUN 18 2013

TODAY: VFR PREVAILS BUT A SHWR COULD BRIEFLY REDUCE THE VSBY TO
MVFR 13Z-14Z. LGT AND VARIABLE WINDS WILL EVENTUALLY ORGANIZE FROM
THE SE AT 10 KTS OR LESS.

TNGT: VFR WITH CIRRUS CIGS PROBABLE FROM UPSTREAM TSTMS. THERE IS
A VERY LOW PROBABILITY FOR A TSTM AFTER 06Z. CONFIDENCE IS NOT
HIGH ENOUGH FOR INCLUSION IN THE TAF. SE WINDS 10 KTS OR LESS.

CIG CONFIDENCE: HIGH
VSBY CONFIDENCE: HIGH
WIND CONFIDENCE: HIGH
WX CONFIDENCE: MEDIUM


&&

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

$$

910 AM UPDATE...PFANNKUCH
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...HALBLAUB