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000
FXUS63 KABR 191644 AAB
AFDABR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ABERDEEN SD
1144 AM CDT WED JUN 19 2013

.UPDATE...REST OF TODAY
EARLIER THIS MORNING HAD A STRONG TO MARGINALLY SEVERE STORM OVER
LYMAN COUNTY...BUT THIS STORM HAS WEAKENED CONSIDERABLY AS IT
MOVED INTO HUGHES COUNTY. DEWPOINTS ARE CLIMBING INTO THE LOW 60S
FOR MOST AREAS WITH TEMPS AROUND 80 DEGREES ALREADY. WILL BE A
WARM AND SOMEWHAT MUGGY DAY WITH A BIT OF INSTABILITY TO BE HAD
OVER THE EASTERN CWA. HI RES MODELS CONTINUE TO INDICATE SCT
DEVELOPMENT OF STORMS OVER THE EASTERN CWA LATER THIS
AFTERNOON...WITH BRIEF HEAVY RAIN AND SMALL HAIL BEING THE MOST
LIKELY ELEMENTS TO DEAL WITH.


&&

.PREVIOUS DISCUSSION...

.SHORT TERM...TODAY THROUGH FRIDAY
THE MAIN CLUSTER OF THUNDERSTORMS THIS MORNING IS LIMITED TO NORTH
CENTRAL NEBRASKA. IT IS HARD TO PICK OUT THE INDIVIDUAL WAVES ON
WATER VAPOR IMAGERY...HOWEVER...MODELS ARE INDICATING THAT
ADDITIONAL SHORTWAVE ENERGY WILL LIFT NORTHEAST THIS MORNING AND
TRACK ACROSS THE CWA THIS AFTERNOON. THE TIMING OF SHORTWAVE
ENERGY DOES RESULT IN MOST CONVECTION REMAINING ELEVATED TODAY...SO
NOT EXPECTING MORE THAN GENERAL THUNDER...WITH PERHAPS AN ISOLATED
STRONG STORM. STRONG SOUTHEASTERLY FLOW WILL BE TRANSPORTING GULF
MOISTURE NORTHWARD HOWEVER...AND SURFACE DEWPOINTS SHOULD BE
RISING INTO THE LOW TO MID 60S TODAY. WINDS WILL BE GUSTY ACROSS
THE WESTERN HALF OF THE CWA TODAY...WITH GUSTS UP TO 35 MPH
POSSIBLE.

A STRONG 40+ KT LLJ SETS UP OVERNIGHT...AND COMBINED WITH STRONG
THETA-E ADVECTION...THERE IS A DECENT CHANCE FOR OVERNIGHT
ELEVATED CONVECTION TO DEVELOP ALONG THE NOSE OF THE LLJ. STORMS
MAY BE STRONG OVERNIGHT AS VERY STEEP MID LEVEL LAPSE RATES AND
PLENTY OF ELEVATED INSTABILITY WILL BE PRESENT. THE EXTENT OF THE
LEFT OVER DEBRIS CLOUDS FROM THIS CONVECTION WILL INFLUENCE
THURSDAY AFTERNOON STORM CHANCES. HOWEVER...BY THURSDAY AFTERNOON
MODELS ARE SHOWING THE SURFACE LOW MOVING INTO THE CENTRAL PLAINS
WITH AN INVERTED TROUGH/COLD FRONT SWINGING ACROSS OUR CWA. CAPE
VALUES ARE RISING INTO THE 2000-3000 J/KG RANGE BY THURSDAY
AFTERNOON...AND THERE WILL BE PLENTY OF AVAILABLE MOISTURE. ALONG
WITH STEEP MID LEVEL LAPSE RATES AND INCREASING 0-6 SHEAR...THERE
CERTAINLY IS A CHANCE FOR STRONG/SEVERE STORMS ON THURSDAY. THE
INHIBITING FACTORS HOWEVER WILL BE RISING 500 MB HEIGHTS AND 700
MB TEMPERATURES RISING TO AROUND 13 C ACROSS THE CENTRAL CWA. IT
LOOKS LIKE THE BEST CHANCE FOR THUNDERSTORM DEVELOPMENT WILL BE ON
THE EDGE OF THE CAP ACROSS THE EASTERN QUARTER OF THE CWA.

FRIDAY...THE SURFACE LOW REORGANIZES WITH THE LOW CENTER
INTENSIFYING OVER WESTERN KANSAS AND NEBRASKA. MULTIPLE WAVES OF
ENERGY WILL TRAVERSE THROUGH SOUTHWEST FLOW ALOFT...AND THE
SURFACE LOW/WARM FRONT WILL MOVE NORTHWARD INTO OUR CWA. MODEL
DIFFERENCES LIMIT FORECASTER CONFIDENCE AT THIS TIME.  NOT ONLY DO
MODELS DIFFER ON THE PLACEMENT OF THE SURFACE BOUNDARY...BUT THE
NAM PUSHES THE UPPER RIDGE EASTWARD MUCH MORE QUICKLY AS COMPARED
TO THE ECMWF/GFS...RESULTING IN 700 MB TEMPERATURES RANGING FROM 5
TO 10 C ACROSS THE CWA. WHEREAS THE GFS/ECMWF SHOW 10 TO 15 C
ACROSS THE CWA. SO...WHETHER THE CAP IS WEAK ENOUGH OR WHETHER
THERE WILL BE STRONG ENOUGH FORCING TO OVERCOME THE CAP IS YET TO
BE SEEN. HOWEVER...IF EITHER OF THE TWO HAPPEN...THE ENVIRONMENT
WILL BE HIGHLY CONDUCIVE TO RAPID AND STRONG CONVECTION FRIDAY
AFTERNOON AND NIGHT.


.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
UPPER LEVEL RIDGING WILL JUST BE EXITING THE REGION TO THE EAST
FRIDAY EVENING...WITH SOUTHWESTERLY FLOW SETTING UP BETWEEN IT AND
LOW PRESSURE OVER THE PACIFIC NORTHWEST. THE LOW TO THE WEST WILL
EVENTUALLY WORK ITS WAY EASTWARD...TRACKING OVER THE NORTHERN
PLAINS AND TO SOUTH CENTRAL CANADA ON SUNDAY. ZONAL FLOW DEVELOPS
ON MONDAY...WITH A WEAK SHORTWAVE SLIDING OVER THE AREA ON
TUESDAY.

SURFACE LOW PRESSURE WILL BE DOMINANT OVER THE NORTHERN AND
CENTRAL PLAINS FRIDAY NIGHT THROUGH THE DAY SUNDAY. ABUNDANT
MOISTURE WILL STREAM OVER THE AREA DURING THIS TIME. STRONG
INSTABILITY DEVELOPS BOTH FRIDAY NIGHT AND SATURDAY NIGHT...WITH
CAPE VALUES EXCEEDING 4000 J/KG AND LIS BETWEEN -8 AND -10 ACROSS
THE CWA. THE LATEST MODEL RUNS HAVE BACKED OFF A BIT ON THE
STRENGTH OF THE CAP FRIDAY NIGHT. THE FAR SOUTHERN CWA LOOKS LIKE
THE MOST LIKELY AREA TO BE CAPPED OFF...BUT THE STRONG INSTABILITY
MAY BE ENOUGH TO OVERCOME THE CAP ELSEWHERE. SATURDAY NIGHT IS
LOOKING A BIT MORE IFFY AT THIS TIME AS H7 TEMPS RISE INTO THE +14
TO +16 DEGREE RANGE. THE PREVIOUS RUNS WERE SHOWING A STRONGER
CAP FRIDAY NIGHT VS SATURDAY NIGHT...SO FOR THE TIME BEING...HAVE
OPTED TO STICK WITH HIGH CHC POPS FOR BOTH PERIODS. THERE MAY BE
SOME LINGERING SHOWERS AND STORMS ON SUNDAY BEFORE THE LOW PRESSURE
SYSTEM PUSHES NORTH...THEN IT LOOKS LIKE WE WILL FINALLY SEE A DRY
PERIOD FROM SUNDAY NIGHT THROUGH MONDAY NIGHT. ANOTHER BOUNDARY
MOVES THROUGH TUESDAY AND MAY BRING ANOTHER CHANCE OF
PRECIPITATION TO THE REGION.

WILL SEE ABOVE NORMAL TEMPERATURES THROUGHOUT THE PERIOD...WITH
DAYTIME HIGHS IN THE 80S AND OVERNIGHT LOWS IN THE 60S.


&&

.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

VFR CONDITIONS WILL PREVAIL ACROSS THE AREA TODAY. LOOK FOR
SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE WESTERN PART OF
THE CWA DURING THE AFTERNOON HOURS...THEN SPREAD EASTWARD DURING
THE EVENING AND OVERNIGHT HOURS. CIGS AND VSBYS MAY BRIEFLY FALL
INTO THE MVFR CATEGORY WITH ANY STRONGER STORMS. DUE TO
UNCERTAINTY IN TIMING AND LOCATION OF THE STORMS...HAVE STUCK WITH
JUST A VCTS MENTION AT ALL TAF SITES FOR NOW.


&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&

$$
UPDATE...TMT
SHORT TERM...SERR
LONG TERM...PARKIN
AVIATION...PARKIN

WEATHER.GOV/ABERDEEN