FXUS63 KOAX 080841
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
341 AM CDT FRI APR 8 2011
.DISCUSSION...TODAY THROUGH SUNDAY NIGHT.
POWERFUL UPPER LEVEL JET OFF THE WEST COAST THIS MORNING FORCING
LARGE WRN CONUS TROF TO DIG THRU THE GREAT BASIN. 500MB HGT FALL
PROGS INDICATING THE UPPER LOW WILL BOTTOM OUT IN THE VICINITY OF
BAJA LATE THIS MORNING THEN BEGIN TO LIFT TWD THE CNTRL PLAINS LATE
THIS AFTN. THUS MAIN ISSUE IS APPROACHING SYSTEM WITH POSSIBLE
THUNDER/SEVERE ACTIVITY THIS WEEKEND. SFC FRONT ASSOCIATED WITH
CONVECTIVE ACTIVITY EARLIER THIS MORNING OVER ERN KS AND MO IS
PROGGED TO ADVANCE LITTLE UNTIL LATER TONIGHT WHEN IT SLOWLY LIFTS
THRU THE CWA. CAP SHOULD GIVE WAY LATE TONIGHT AND THINK CONVECTION
WILL BE MOST LIKELY ON NOSE OF INCREASING LLVL JET CLOSE TO SFC BNDRY
OVER THE NRN CWA INTO SATURDAY MORNING. IN THE MEANTIME...SFC LOW
ASSOCIATED WITH AFOREMENTIONED BNDRY PROGGED TO BE DEEPENING IN ERN
CO MAKING INFLUX OF MOIST/UNSTABLE AIRMASS INTO WARM SECTOR LIKELY
SAT AFTN. FOR NOW HAVE PRETTY MUCH RELIED UPON MOVEMENT OF BNDRY LYR
MOIST CONVG/INSTABILITY AXIS/TPI PROGS TO PIN DOWN POPS. NO DOUBT...
COMBINATION OF MU-CAPES AROUND 2500-3500J/KG...EFFECTIVE SRH...DEEP
LYR BULK SHEAR DIFFERENCE WILL PROVIDE FAVORABLE ENVIRONMENT FOR
SUPERCELL DEVELOPMENT LEADING INTO SAT EVENING. ON SUNDAY THE SFC LOW
FINALLY LIFTS TWD THE UPPER MIDWEST AND SWEEPS A COLD FRONT INTO THE
CNTRL PLAINS. PW VALUES STILL AROUND AN INCH OR SO PER BOTH NAM/GFS
WITH FROPA ACROSS THE CWA IN THE AFTN. NAM SHOWING POSSIBLE SVR
STORMS NW IA INTO PARTS OF NERN NEB...NOT SO WITH THE GFS. WILL LEAVE
SMALL POPS IN PLACE SUNDAY NIGHT IN CASE OF LINGERING POST-FRONTAL
ACTIVITY. AS FOR TEMPS...WARM SECTOR OVER THE REGION SHOULD ALLOW
HIGHS TO PUSH WELL INTO THE 80S SOUTH...WITH MID/UPPER 70S NORTH.
LATE ARRIVAL OF COLD FRONT SUNDAY SHOULD ALLOW AFTN TEMPS TO REACH
M70S-L80S MOST LOCATIONS.
DEE
&&
.AVIATION...
06Z TAFS
MVFR CEILINGS ARE EXPECTED INTO THE MORNING HOURS AT ALL 3 TAF
SITES. SOME LOCAL IFR WILL BE POSSIBLE THROUGH 15Z...BUT MAINLY AT
OFK/LNK. WITH THE EASTERLY LOW LEVEL FLOW...THESE CEILINGS MAY BE
HARD TO GET RID OF THROUGH THE DAY...BUT SHOULD INCREASE IN HEIGHT
TO VFR BY AFTERNOON. NO PRECIPITATION IS EXPECTED THROUGH THE PERIOD
THOUGH...BUT MVFR CEILINGS ARE LIKELY TO DEVELOP AGAIN AFTER 03Z ON
SATURDAY AS THE LOW LEVEL JET INCREASES. THIS MAY ALLOW FOR SOME
LOW-LEVEL SHEAR TO DEVELOP AT OMA/LNK AFTER 06Z SAT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$