399 FXUS63 KOAX 130022 AFDOAX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 722 PM CDT FRI JUL 12 2013 .AVIATION... 00Z TAFS FOR KOMA...KOFK...KLNK VFR CONDS ARE EXPECTED THROUGH THE PERIOD. WIND GUSTS WILL DIMINISH THIS EVENING BUT SHOULD AGAIN DEVELOP BY MID TO LATE MORNING ON SAT AT OFK/LNK WITH WINDS AOA 12 KT LIKELY AT ALL SITES FROM THE SE. OTHERWISE WE WILL SEE AN INCREASE IN MID LEVEL CLOUDS ON SAT AT LNK/OMA FROM LATE MORNING THROUGH THE END OF THE TAF PERIOD. && .PREV DISCUSSION... /ISSUED 303 PM CDT FRI JUL 12 2013/ DISCUSSION... UPPER RIDGE WILL REMAIN IN PLACE ACROSS THE PLAINS TONIGHT...WHILE A VERY SUBTLE WAVE MOVES OFF THE FRONT RANGE. AN AREA OF LOW PRESSURE AND ASSOCIATED SURFACE TROUGH ACROSS THE DAKOTAS WILL BECOME A FOCUS FOR CONVECTION OVERNIGHT...THAT SHOULD REMAIN MOSTLY TO OUR NORTH...BUT COULD CLIP THE NE/SD BORDER REGION AFTER MIDNIGHT. AS LOW LEVEL JET STRENGTHENS...THEN VEERS TONIGHT...THIS COULD TRIGGER ISOLATED THUNDERSHOWERS UNDERNEATH THE RIDGE AXIS...SIMILAR TO LAST NIGHT. BOTH THE NAM AND GFS MODELS SUGGEST THIS...BUT OTHER MODEL SUITES REMAIN DRY. BEST CHANCES WOULD BE IN SOUTHEAST NEBRASKA...BUT A WEAK MOIST AXIS DOES EXTEND NORTHWARD ALONG THE MISSOURI RIVER CORRIDOR. IF SOMETHING DOES DEVELOP...IT COULD LINGER FOR AN HOUR OR TWO SATURDAY MORNING IN SOUTHEAST NEBRASKA...SIMILAR TO WHAT HAPPENED THIS MORNING. FOR SATURDAY AND SATURDAY NIGHT...THE UPPER LOW THAT IS CURRENTLY MOVING THROUGH THE APPALACHIAN MOUNTAINS WILL CONTINUE TO RETROGRADE WEST. IT SHOULD BE FAR ENOUGH WAY TO NOT INFLUENCE OUR AREA WITH WEAK RIDGING REMAINING IN PLACE ACROSS THE PLAINS. HOWEVER...AS WITH PREVIOUS NIGHTS...WITH STRENGTHENING LOW LEVEL JET...CANNOT RULE OUT ISOLATED NOCTURNAL CONVECTION UNDER THE RIDGE WITHIN A MOIST AXIS...ESPECIALLY AS CYCLONIC FLOW AROUND THE LOW THAT WILL BE IN MISSOURI AT THE TIME INCREASES BY DAYBREAK SUNDAY. PRECIP WOULD BE MOVING EAST TO WEST...AND COULD LINGER IN NORTHEAST NEBRASKA SUNDAY MORNING...BUT THEN DRY FOR SUNDAY AFTERNOON AND NIGHT. THE EARLY PART OF NEXT WEEK STILL SHOWS THE CLOSED UPPER LOW DRIFTING SOUTHWEST INTO THE SOUTHERN HIGH PLAINS...WHILE UPPER RIDGE BACKBUILDS ACROSS THE MID MISSOURI RIVER VALLEY. THIS WOULD MOSTLY LEAD TO A DRY PATTERN THROUGH THE REMAINDER OF THE WEEK...BUT WILL HAVE TO WATCH FOR SPOTTY CONVECTION BOTH TUESDAY AND WEDNESDAY SOUTH OF I80...BUT CONFIDENCE IS LOW. THE RIDGE DOES APPEAR TO FLATTEN LATER IN THE WEEK IN RESPONSE TO A TROUGH MOVING THROUGH SOUTHERN CANADA. BOTH THE GFS AND ECMWF SUGGEST THAT A COOL FRONT COULD MOVE INTO THE AREA ON FRIDAY...WITH THE ECMWF JUST SLIGHTLY FASTER...THUS HAVE INTRODUCED A SMALL CHANCE OF THUNDERSTORMS...BUT AGAIN...CONFIDENCE IS LOW DUE TO TIMING DIFFERENCES IN THE MODELS. DEWALD && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$