717 FXUS63 KOAX 012058 AFDOAX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 358 PM CDT SUN APR 1 2012 .DISCUSSION... FORECAST CONCERNS IN THE SHORT TERM WILL BE THE EXTENT OF ANY LOW CLOUDS AND FOG AHEAD OF THE COLD FRONT TONIGHT WITH VERY MILD LOWS...THEN CHANCE OF PRECIPITATION MONDAY THROUGH WEDNESDAY AND POTENTIAL FOR WIND HEADLINES MONDAY. AT 20Z SURFACE LOW PRESSURE WAS CENTERED OVER WEST CENTRAL SOUTH DAKOTA WITH A FRONT EXTENDING SOUTHEAST THROUGH SOUTH DAKOTA TOWARD DES MOINES. AT 20Z...TEMPERATURES WERE IN THE 80S AND 90S WITH DEWPOINTS IN THE 40S...50S AND 60S WITH SOUTHEAST WINDS AT 15 TO 25 MPH. A NEW RECORD WAS SET AT NORFOLK AS THEY WERE AT 90 DEGREES BY 3PM. THE OLD RECORD WAS 88 IN 2003. THE DRYLINE/WINDSHIFT WAS EAST OF VALENTINE AND THEDFORD AS THEY HAD DEWPOINTS IN THE 20S/30S. TONIGHT THERE IS SOME GOOD THETA-E ADVECTION AND BOTH THE NAM/GFS SHOW POOLING OF H85 DEWPOINTS OVER ECNTRL NEBRASKA INTO WRN IOWA AT 00Z AND QUICKLY LIFTING THIS MOISTURE NORTHEAST THROUGH 06Z. THERE MAY BE SOME LOW CLOUDS THAT DEVELOP...BUT THE FORECAST SOUNDINGS ARE SHOWING IT WILL BE CAPPED THIS EVENING. THERE WAS SOME PATCHY FOG AROUND THIS MORNING AND LOW LEVEL RH LEVELS/LOW DEWPOINT DEPRESSIONS AGAIN FOR MONDAY MORNING. WILL MENTION FOG AND SHOULD SEE SOME STRATUS. MILD SOUTHEAST FLOW SHOULD HOLD LOWS TO THE MID 50S NORTHWEST TO THE UPPER 60S FOR SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. THE SURFACE FRONT BY 12Z SHOULD IN THE VICINITY OF A LINE FROM WAYNE TO COLUMBUS AND PUSHING THROUGH THE FORECAST AREA BY 00Z. THE NEW 18Z NAM WAS A LITTLE FASTER WITH THE TIMING OF THE FRONT. THERE IS SOME LIFT AND STEEP LAPSE RATES...HOWEVER THE MAIN SHORTWAVE ENERGY LIFTS TO OUR NORTH. THERE WILL BE CLOUDS WITH THE FRONT AND FOR NOW HAVE SOME LOW POPS IN NORTHEAST NEBRASKA AND COULD SEE SOME LOW POPS IN THE SOUTHEAST PART OF THE FORECAST AREA TOO. STRONG WINDS ARE A CONCERN FOR MONDAY AND MONDAY NIGHT. CURRENTLY HAVE WINDS 15 TO 30 MPH WITH GUSTS 40 MPH. MAY NEED A WIND ADVISORY ESPECIALLY FOR PARTS OF NORTHEAST NEBRASKA WHERE WINDS ARE EXPECTED TO BE A LITTLE STRONGER BEHIND THE COLD FRONT. MONDAY NIGHT...THE NORTHERN ENERGY TRACKS TO OUR NORTHEAST WHILE THE SOUTHERN PORTION OF THE MID LEVEL TROF CLOSES OFF OVER THE SOUTHERN PLAINS. THE STORM SYSTEM MAY CONTINUE SHOWER AND ISOLATED THUNDERSTORM CHANCES ACROSS SOUTHERN NEBRASKA AND SOUTHERN IOWA THROUGH TUESDAY NIGHT. THEN FARTHER NORTH ACROSS MUCH OF EASTERN NEBRASKA AND WESTERN IOWA WEDNESDAY...WITH LIKELY CHANCES ACROSS THE SOUTH. WEDNESDAY NIGHT THROUGH SUNDAY.THE FORECAST CONCERN FOR THE EXTENDED WILL BE THE CHANCE FOR THUNDERSTORMS WEDNESDAY NIGHT AND AGAIN FRIDAY NIGHT THROUGH SATURDAY. THE SYNOPTIC PATTERN STARTS OUT WITH THE FORECAST AREA ON THE COOL SIDE OF THE LOW PRESSURE SYSTEM CENTERED OVER SOUTHERN MISSOURI AND THE MID TROPOSPHERIC LOW OVER EASTERN KANSAS. PARTS OF THE SOUTHERN FORECAST AREA WILL BE ON THE NORTHERN FRINGE OF THE PRECIPITATION AREA AND THE PRECIPITATION SHOULD GRADUALLY MOVE OUT OF SOUTHEAST NEBRASKA AND SOUTHWEST IOWA THURSDAY MORNING. MEANWHILE...A MUCH LARGER SYSTEM WILL ALREADY BE ONSHORE...WITH A LARGE CLOSED MID LEVEL LOW PRESSURE SYSTEM OVER THE PACIFIC NORTHWEST. THIS STORM SYSTEM WILL BRING UPSLOPE FLOW TO THE WESTERN PLAINS THURSDAY NIGHT AND THE COLD FRONT WILL PUSH EASTWARD FRIDAY NIGHT AND SATURDAY. THE 12Z GFS IS SLIGHTLY FASTER WITH THE WEEKEND SYSTEM THAN THE 00Z RUN. THE PATTERN LOOKS VERY DYNAMIC AND THE SURFACE LOW LIFT NORTH FROM NORTHERN NEBRASKA INTO ERN NORTH DAKOTA DURING THE DAY SATURDAY. 0-6KM BULK SHEAR VALUES ARE QUITE HIGH AND MID LEVEL LAPSE RATES ARE STEEP...HOWEVER THE CAPE IS LACKING. THE MORE WIDESPREAD PRECIPITATION WILL BE CLOSER TO THE SURFACE LOW...BUT WILL MAINTAIN THE CHC FOR SHOWERS AND THUNDERSTORMS AHEAD OF AND WITH THE COLD FRONT. TEMPERATURES IN THE EXTENDED WILL REMAIN ABOVE NORMAL WITH LOWS IN THE 40S AND HIGHS IN THE 50S THURSDAY...60S AND 70S FRI THRU SAT AND COLDER SUNDAY. WIND HEADLINES MAY BE NEED SATURDAY AND SATURDAY EVENING WITH STRONG WINDS AHEAD OF AND BEHIND THE FRONT. && .AVIATION... 18Z TAFS FOR KOFK...KOMA AND KLNK. AVIATION CONCERNS INCLUDE LOW CLOUD/FOG POSSIBILITY LATE TONIGHT AND THEN FRONTAL TIMING/WIND SHIFT ON MONDAY. FOR TODAY SRLY WINDS SHOULD INCREASE SOME INTO EARLY AFTERNOON AT KOFK WITH OCCASIONAL GUSTS EXPECTED AT KOMA AND KLNK BUT VFR CONDITIONS SHOULD PREVAIL THROUGH THIS EVENING. FOR TONIGHT...STRATUS WHICH DEVELOPED SW-S OF THE REGION THIS MORNING COULD REDEVELOP FARTHER NEWD MONDAY MORNING AHEAD OF ABOVE MENTIONED COLD FRONT AND IFR/LOW MVFR CIGS WERE FORECAST AT ALL SITES. SOME FOG COULD ACCOMPANY LOW CLOUDS AND A PERIOD OF IFR VSBY RESTRICTION WAS INCLUDED AT KLNK WHICH WAS CLOSEST TO SIMILAR CONDITIONS THIS MORNING. COLD FRONT SHOULD MAKE IT TO KOMA AND KLNK BEFORE 02/18Z WITH NW WINDS INCREASING MARKEDLY BEHIND IT...BUT PROBABLY NOT UNTIL AFTER 02Z/18Z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ ZAPOTOCNY/CHERMOK