239 FXUS63 KLBF 241740 AFDLBF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTH PLATTE NE 1140 AM CST THU DEC 24 2015 .SYNOPSIS... ISSUED AT 359 AM CST THU DEC 24 2015 AT H5 FAIRLY ZONAL FLOW OVER THE WESTERN HALF OF LOWER 48. TROUGH ENTERING THE GREAT LAKES REGION WITH RIDGE BUILDING AHEAD THROUGH THE NORTHEAST CONUS. STRONGER WAVE MOVING ACROSS CENTRAL PLAINS AND MOVING INTO THE PACIFIC NORTHWEST. AT THE SURFACE STRONG COLD FRONT OVER THE OHIO VALLEY INTO LOUISIANA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 359 AM CST THU DEC 24 2015 MODELS PERFORMING FAIRLY WELL IN THE NEAR TERM AND WILL WEIGHT FORECAST TOWARDS NAM. AREA OF LIGHT SNOW OVER SOUTHWEST NEBRASKA MOVING EAST AROUND 20 TO 25 KTS WILL HAVE THE BULK OF IT MOVING INTO SOUTH CENTRAL NEBRASKA BY 12Z. HAVE CONTINUED TO CARRY A LINGERING MENTION THROUGH NORTH CENTRAL THROUGH 15Z. LIGHT SOUTHWEST WINDS TODAY WITH CLOUDS CLEARING FROM WEST TO EAST THROUGH THE DAY...THEN INCREASING CLOUDS FROM SOUTHWEST INTO NORTHEAST OVER NIGHT WHICH WILL HELP TOP KEEP TEMPERATURES UP. SNOWFIELD TO THE NORTHWEST WILL CONTINUE TO SKEW TEMPERATURE FIELD. HIGHS OVER THE SNOW FIELD IN THE LOW 30S AND UPPER 30S TO AROUND 40 FROM SOUTHWEST INTO NORTH CENTRAL. LOWS TONIGHT IN THE SINGLE DIGITS NORTHWEST AND TEENS OVER THE REMAINDER OF WESTERN AND NORTH CENTRAL NEBRASKA. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 359 AM CST THU DEC 24 2015 POTENT STORM SYSTEM CHRISTMAS DAY INTO THE WEEKEND IS THE MAIN FOCUS FOR THE LONG TERM PERIOD. MODELS ARE SHOWING A TROUGH DIG INTO THE 4 CORNERS REGION BY FRIDAY. A SHORT WAVE WILL EJECT FROM THE TROUGH AND PUSH ACROSS THE CENTRAL ROCKIES DURING THE DAY AND ACROSS THE HIGH PLAINS FRIDAY OVERNIGHT INTO SATURDAY. INITIALLY FRIDAY LOWER LEVEL IS LIMITED IN MOISTURE AND TOP DOWN SATURATION TO KEEP DAYTIME SNOW LIGHT. THE MODELS CONTINUE TO FAVOR THE TRACK OF THE WAVE ACROSS THE PANHANDLE AND NORTHERN NEBRASKA. NO CHANGES IN THE ONGOING WINTER STORM WATCH. SNOW OF AROUND 6 INCHES POSSIBLE...MAINLY FRIDAY NIGHT INTO SATURDAY. COUPLE CONCERNS WITH THIS SYSTEM. FIRST WILL BE THE WARM SURGE AHEAD OF THE SFC LOW AS IT TRACKS E ACROSS CO AND KS FRIDAY. TEMPS CHRISTMAS DAY ACROSS THE EAST SHOULD PUSH ABOVE THE FREEZING MARK AND PRECIP COULD BE A MIX OF SNOW AND RAIN. THEN AS TEMPS COOL OVERNIGHT...A WARM AND DRY LAYER SURGE ACROSS CENTRAL NEB. THIS COULD BE ENOUGH TO CUT THE ICE CRYSTALS INTRODUCTION AND RESULT IN SOME PATCHY FREEZING DRIZZLE. AS THE COLD AIR SURGES SATURDAY MORNING...BUFKIT SOUNDINGS SUGGEST SATURATION AND A CHANGE TO ALL SNOW. ANOTHER CONCERN WILL BE CONVECTION ACROSS THE SOUTHERN/CENTRAL PLAINS. THIS COULD LIMIT THE MOISTURE BEING WRAPPED INTO THE SYSTEM AND REDUCE SNOW AMOUNTS. HOWEVER MODELS GENERALLY FAVORING THE BEST CONVECTION SATURDAY AFTERNOON...AFTER THE MAJORITY OF THE SNOW IS EXPECTED TO HAVE FALLEN. IT MAY END UP JUST ENDING THE SNOW A PERIOD EARLIER THAN CURRENTLY ANTICIPATED. AFTER THE SNOW ENDS SATURDAY NIGHT...CLEARING HIGH PRESSURE SHOULD ALLOW FOR TEMPS TO TANK. LOWS OVER THE DEEPEST SNOW PACK LIKELY TO FALL BELOW ZERO. THE LOW ACROSS THE 4 CORNERS WILL PUSH ACROSS THE SOUTHERN PLAINS THEN LIFT NORTHEAST ACROSS THE CENTRAL PLAINS EARLY NEXT WEEK. THE MODELS ARE STRUGGLING WITH THE TRACK...BUT BOTH KEEP THE LOW TO THE SE OF THE CWA. THE QUESTION IS HOW FAR TO THE SOUTHEAST. THE EC CONTINUES TO BE DEEPER AND BRING THE WRAP AROUND INTO THE CWA...WHILE THE GFS FAVORS A FURTHER TO THE SE TRACK. WILL CONTINUE TO KEEP POPS LOW AND WAIT FOR BETTER AGREEMENT. EITHER WAY...TEMPS TO BE AT OR BELOW NORMAL THANKS TO THE EXPECTED SNOW PACK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1140 AM CST THU DEC 24 2015 FOR THE 18Z TAF...FORECAST CONFIDENCE INITIALLY IS STRONG UP THROUGH THE OVERNIGHT...HOWEVER LATE IN THE TAF PERIOD...CONFIDENCE WANES. THIS IS DUE TO LOCATIONAL AND TIMING DIFFERENCES OF THE MODEL GENERATED PRECIPITATION. WITH THE FORECAST...WILL KEEP MOST TAF SITES AT VFR OR HIGHER...SAVE FOR NORTHWEST NEBRASKA AND KVTN...WHERE AT A MINIMUM LOW STRATUS WILL BUILD EAST AND IMPACT THE TERMINALS. IF PRECIPITATION IS REALIZED IN THIS TAF PERIOD...A MIX OF -SN AND -FZDZ IS POSSIBLE...HOWEVER THE GREATER POTENTIAL FOR IMPACTS TO THE AVIATION COMMUNITY COMES BEYOND 18Z. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY AFTERNOON FOR NEZ004>008-094. && $$ SYNOPSIS...POWER SHORT TERM...POWER LONG TERM...MASEK AVIATION...JACOBS