AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 223 PM CST SAT JAN 01 2000 ONCE AGAIN TODAY...TOUGH FORECAST FOR NO HEADLINES WITH ALL FORECAST ELEMENTS IN QUESTION. YESTERDAY'S FORECAST ACTUALLY WORKING OUT WELL FOR THE CURRENT TIME PERIOD WITH S/W CONUS SYSTEM AROUND 4 CORNERS. WARM ADVECTION CLOUDS AND A FEW SPRINKLES INVADING IA FROM THE SW. ITS THIS FEATURE AND PTYPE IT BRINGS THAT MAY PROVIDE THE MOST DIFFICULT FORECAST CHALLENGE. ELSEWHERE AT UPPER LEVELS SYSTEM COMING ASHORE IN PAC NW TO EFFECT IA ON MONDAY NOT TUESDAY. AT THE SFC...DOUBLE LOW STRUCTURE OVER WRN KS TO NE CO WITH STRNY FRONT FROM KGLD TO KCID. THIS LIKELY TO MOVE BACK NORTH AS A WARM FRONT THIS EVENING AS ANOTHER NORTHWARD MOVING WARM FRONT FROM KCNK TO KCOU CATCHES UP WITH IT. ARCTIC AIR WELL NORTH INTO ND AND NRN MN NOT TO EFFECT NEAR TIME PERIODS. AS OFTEN HAPPENS WITH SYSTEMS COMING ASHORE...WHETHER IN THE NW OR SW...BEGIN TO BE HANDLED BY ETA. THIS IS AGAIN HAPPENING THOUGH AVN SHOWS VERY SIMILAR SOLN TOO. WILL GO THAT WAY. PRIMARY CHALLENGE TONIGHT IS ONSET OF PRECIP...THATS ALREADY BEGINNING TO OCCUR WITH A FEW SPRINKLES LIKELY HITTING GROUND FROM DNS AND WEST. WILL GO WITH THAT LINE OF THINKING MOST AREAS TONIGHT. FROM POCAHONATAS COUNTY TO MCW AND POINTS NORTH THOUGH...A LITTLE VERY LIGHT...INTERMITTENT FZRA COULD OCCUR LATE THIS EVENING AS PARTIAL THICKNESSES BEGIN TO FALL. ALSO DUE TO DRY LOW LEVELS...WILL GET SOME COOLING TO DUE EVAP. MOST PLACES THO WON'T SEE TEMPS FALLING ENOUGH FOR THAT. 18Z RUC ALSO LEANING AWAY FROM FZRA POTENIAL IN NORTH AS THICKNESSES AND TEMPS JUST AREN'T COOL ENOUGH. SUNDAY...AS THICKNESSES SLOWLY FALL...MAY SEE SOME MORNING FLURRIES NRN HALF CWA WITH SPRINKLES SOUTH AS 4 CORNERS SYSTEM MOVES THROUGH PLAINS AND MISSOURI VALLEY. GUID TEMPS REASONABLE AND IN AGREEMENT. COULD BE A LITTLE SUN SHOW UP IN WRN CWA LATE...BUT WITH NEXT BATCH OF HIGH CLOUDINESS ONCOMING...WILL NOT BE TOO MUCH. SUNDAY NIGHT TO REMAIN QUITE AS WE'RE STILL BARELY BETWEEN SYSTEMS. GUID TEMPS BEGIN TO DIVERGE. WILL SIDE TO COOLER NUMBERS WITH CAA PERHAPS OVERCOMING CLOUDY SKIES. FOR MONDAY...YESTERDAYS TUES SYSTEM HAS SPED UP AND WOULDN'T BE SURPRISED TO SEE THIS HAPPEN WITH VERY FAST JET OFF NW PAC COAST. TEMPS NEAR THE FREEZING MARK IN THE SOUTH WITH LITTLE RISE ANYWHERE. 50 POP SOUTH FOR R/S LESSER POPS FARTHER NORTH FOR ALL S. EXTENDED...REMAINS PRETTY TOUGH WITH DIFFERING SOLNS ESP BY DAY 5. AVN KEEPS CYCLONIC FLO AND PLENTY OF RH OVER IA...WITH COLD TEMPS WILL RUN WITH FLURRIES. WED TO BE DRY EXCEPT FOR CAN/US BORDER LOW AND TRAILING COLD FRONT PER MRF/CAN/ECMWF SO NRN IA MAY SEE SOME LIGHT SNOW. BY THU...MANY DIFF SOLNS AND WILL SIDE WITH DRY...UNLIKE VERY PESSIMISTIC MRF. .DSM...NONE SEARCY ia SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 815 PM MST SAT JAN 1 2000 ...WILL UPDATE STATE AND TFX ZONE FORECASTS... S/WV TROF OVER ERN WA/OR THIS EVE SPREADING MOIST ACROSS WRN MT. CONSIDERABLE COLD AIR ASSOC WITH THIS FEATURE AS 00Z ANAL SHOWS -35 DEGC 500 TEMPS AND -15 DEGC 700 TEMPS. THIS MORNINGS MODELS DIFFERED WITH ASSOC VORT PATTERN...BUT WERE SIMILAR BRINGING S/WV TROF E OF DVD BY 12Z SUN. AHEAD OF THIS FEATURE CANADIAN CDFNT IS SAGGING ALONG HI-LINE BRINGING LOW CLDS/FOG AND POSSIBLY SOME SNOW LATER TONIGHT. RUC SHOWS WAVE ON BOUNDARY MOVING ACROSS SE BC AND NRN E SLOPES LATER TNT. THIS SHOULD KEEP BOUNDARY FROM BACKDOORING INTO GTF. FOR NOW WILL UPDATE FOR MORE WIDESPREAD SNOW DEVELOPING OVER NRN ROCKIES WITH APPROACHING S/WV TROF. WILL ALSO UPDATE FOR MIN TEMPS BEHIND CDFNT ALONG HI LINE AND A CHANCE OF LIGHT SNOW. EYSSAUTIER GTF 1342 HLN 1332 HVR 2353 mt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BINGHAMTON NY 937 AM EST SAT JAN 1 2000 THE GREAT START TO THE NEW YEAR FOR NON WINTER ENTHUSIASTS WILL CONTINUE THRU THE WEEKEND. CLIPPER RACING ACROSS CNTRL ONTARIO THIS AM WITH MID CLOUDS SCOOTING THRU NRN SXNS OF CWFA. THESE SHOULD MOVE OUT EARLY THIS AFTN PER SATL TRENDS AND 12Z RUC RH FCSTS...THEN JUST SOME INCIDENTAL THIN CI. LOW CLDS MOVG NWD THRU WV/VA LOOK TO BE HELD AT BAY TIL EVENING AND FOG IN WY VLY LIFTING OUT AS WELL. XPCT ALL AREAS WL BASK IN WINTER SUN AND MILD SWLY FLOW FOR RMNDR AFTN. SOUNDINGS AND LAMP FCSTS GET MAX T'S INTO 40S ACROSS THE BOARD. CURRENTS VERIFYING WITH GUIDANCE TRENDS THUS FAR AS INVERSION BREAKS SO ONLY MINIMAL TWEEKS TO SKY CONDITS ARE EXPECTED THIS UPDATE. WL HOPE FOR MORE STABLE BUFR DATA TODAY TO EVALUATE FZDZ SITN TONITE AS POLAR HIPRES BEHIND CLIPPER SAGS FRONT INTO AREA AND MOIST SWLY FLOW RIDES OVER COLD DOME. WRKZONES OUT AS ADMBGM...FINALS ABOUT 10 AM. .BGM...NONE. BREWSTER ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 1000 AM EST SAT JAN 1 2000 IT IS APPARENT THE CRNT FCST WILL HAVE TO UNDERGO SOME MINOR SURGERY THIS AM WITH LOW CLD DECK AND LIGHT RAIN ACRS CENT SC MOVING NE TOWARD CWFA. THIS IS RESULTING FROM A WEAK H50 S/W - H70 DIFF THAT RUC CARRIES OVR OUR REGION THIS AFTN. SFC RIDGE AXIS CRNTLY ALLOWING CLDS TO ERODE A BIT ATTM...BUT RUC WEAKENS THIS FEATURE OVER TIME AND CLDS/SPRINKLES SHOULD EDGE TOWARD THE COAST BY LATE AFTN. MOSTLY CLOUDY SW ZONE GROUPS/BECOMING (PC/MC?) NE ZONES. LIGHT WINDS BECOMING EAST. TEMPS WILL BE LOWERED A CAT MOST AREAS AND PERHAPS TWO CAT FURTHER INLAND. CWF...WILL GO WITH N WIND 10 KT OR LESS TO START OUT WITH AND SWING ARND TO THE E. SEAS 2 FT OR LESS. .ILM...NONE. JFP nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE COLUMBIA SC 230 PM EST SAT JAN 1 2000 NEW YEAR STARTS OUT ON A MILD NOTE. SFC HI PRES CNTRD OFF NC CST HELPING TO KEEP WARM AMS IN PLACE OVR SERN STATES. PTCHY FOG JUST RECENTLY BURNING OFF WITH SKIES BECMG PTCLDY AS WK S/W EXITS STATE AS SHOWN BY LATEST RUC. MODELS IN DECENT AGREEMENT DEPICTING SW FLOW ALF WHICH WL CONTINUE THRU PD. SERIES OF S/WS CARVE OUT NXT TROF AS IT APPROACHES MID-SECTION OF NATION BY MON AM. MODELS A BIT SLOWER NOW WITH THIS FEATURE...ESPECIALLY AVN. WK S/W WL MOV THRU STATE SUN BUT XPCT NO PRECIP ATTM...ALTHO WITH GD LOW-LVL MSTR AVBL...MAY SEE MORE PTCHY FOG LINGERING INTO THE LATE AM HRS SUN WITH LGT S WNDS. PTCLDY-MCLDY SKIES WL PERSIST THRU PD AS LWR LAYERS OF AMS BECOME MORE MOIST INTO SUN. MAY SEE SLGT CHC OF RAIN LATE MON AS TROF GETS CLOSER. IN THE EXTENDED...UPR TROF SWINGS OFSHR WED. RDG BLDS THRU MUCH OF REMAINDER OF WK WITH NR SEASONABLE TEMPS. CONSENSUS OF GUIDANCE NUMBERS FOR TEMPS LUKS REASONABLE. PRELIM CCFS CAE BE 47/75/53/75/54 22000 AGS BE 46/75/52/74/52 22000 .CAE...NONE. BC sc AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA NATIONAL WEATHER SERVICE ABERDEEN SD 1020 AM CST SAT JAN 1 2000 CONCERNS THIS MORNING DEAL WITH CLOUDS AND TEMPS. RUC SHOWS LOW LEVELS DRYING SOMEWHAT DURING DAY AS VORT MAX'S MOVE NORTH AND SOUTH OF THE CWA. THIS BLENDS WELL WITH WHAT SAT PIX ARE SHOWING AT THE MOMENT. WINDS MOST AREAS HAVE ALREADY TURNED EAST-SOUTHEAST IN ADVANCE OF LEE TROF DEVELOPING. A FEW BREAKS IN CLOUD COVER MAY HELP TEMPS TO RECOVER SOMEWHAT...ALTHOUGH A E-SE WIND IS NOT CONDUCIVE FOR WARMING. WILL LEAVE TEMPS ALONE FOR NOW AND SEE HOW THEY LOOK AFT 18Z. AS FOR MENTION OF FLURRIES...RUC TIME SECTION SHOWS DRY SLOT FROM 850-700MB AS ADVERTISED ON YESTERDAY'S MODEL RUNS. WITH LITTLE MOIST TO WORK WITH...AND THE FACT THAT ANYTHING THAT DOES FALL WILL MOST LIKELY EVAPORATE AS IT HITS THE DRY LEVEL...WILL PULL MENTION OF FLURRIES. UPDATES OUT SHORTLY. .ABR...NONE. HINTZ sd NORTHERN ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FLAGSTAFF AZ 900 PM MST SAT JAN 1 2000 .SYNOPSIS...ANOTHER STORM SYSTEM OVER CALIFORNIA WILL MOVE RAPIDLY SOUTH TONIGHT AND WILL BEGIN TO AFFECT NORTHERN ARIZONA BY EARLY SUNDAY MORNING. THIS STORM WILL BRING ANOTHER ROUND OF SNOW TO NORTHERN AND CENTRAL ARIZONA. SEVERAL INCHES OF NEW SNOW ARE POSSIBLE BY SUNDAY AFTERNOON ACROSS MANY OF THE SAME AREAS AFFECTED TODAY. THIS SECOND SYSTEM WILL BRING EVEN COLDER AIR TO THE REGION THROUGH EARLY MONDAY. HIGH PRESSURE WILL BUILD MONDAY AFTERNOON THROUGH WEDNESDAY FOR A WARMING AND DRYING TREND. ANOTHER STORM WILL BRING THE CHANCE FOR SNOW AGAIN BY THURSDAY. DISCUSSION...RATHER COMPLEX SITUATION THIS EVENING. S/WV THAT BROUGHT SNOW TO CWA EARLIER TODAY HAS MOVED EAST. RADAR/SFC OBS INDICATE LITTLE ACTIVITY ACROSS CWA ATTM. SFC LOW OVER CENTRAL NV WITH TRAILING COLD FRONT CURRENTLY MOVING THRU SOUTHERN NV IS PRODUCING LITTLE IN THE WAY OF WEATHER. EXPECT FRONT TO MOVE THRU NORTHERN CWA OVERNIGHT. OF GREATER INTEREST IS THE S/WV CURRENTLY SEEN OVER NORTHERN CALIF. THIS FEATURE TO MOVE RAPIDLY SOUTH TONIGHT PUSHED BY 100+KT JET. THIS S/WV PROGGED TO ENTER WESTERN AZ BETWEEN 09Z-12Z SUNDAY MORNING. 01Z RUC/00Z ETA INDICATE STRONG PVA/UVV ASSOCIATED WITH THIS FEATURE MOVING ACROSS CWA DURING THE DAY TOMORROW. 00Z SOUNDINGS AT FGZ AND OVER SOUTHERN NV SHOW 0.20 INCHES OF PRECIPITABLE WATER...SIMILAR TO THIS MORNING'S SOUNDING. MODELS NOT INDICATING DEEP MOISTURE BUT DO SHOW PLENTY OF LOWER LEVEL MOISTURE. THE OROGRAPHIC WIND COMPONENT TOMORROW NOT AS STRONG AS TODAY SO EXPECT SNOWFALL ON SUNDAY TO BE BELOW ADVISORY CRITERIA...IN THE 2-4 INCH RANGE. WILL UPDATE ZONES TO ADJUST TIMING FOR ONSET OF PRECIP LATER TONIGHT. DF .FGZ...NONE. az SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO 315 AM MST SUN JAN 2 2000 RATHER COMPLICATED FORECAST WITH QUITE QUICK UPPER FLOW PATTERN. MAIN WEATHER CONCERNS IN SHORT TERM ARE IMPACT OF 2ND RATHER POTENT UPPER WAVE MOVING IN THE PROXIMITY OF THE CWFA LATER TODAY/TONIGHT AND AMOUNT OF COOL DOWN IN SOMEWHAT LONGER TERM. CWFA ENJOYING REPRIEVE IN WAKE OF SMALL BUT RATHER POTENT SYSTEM CURRENTLY TRAVERSING NORTH-CENTRAL KANSAS. LATEST ETA/RUC MODELS PROJECT 1ST POTENT SHORTWAVE TO CONTINUE TO PUSH WELL EAST OF CWFA DURING SUNDAY MORNING WHILE 2ND STRONG WAVE DEVELOPS OVER CENTRAL ARIZONA BY 18Z SUNDAY. THIS 2ND SYSTEM IS THEN PROJECTED BY ETA TO PUSH MAINLY ACROSS CENTRAL AND SOUTHERN NEW MEXICO THIS AFTERNOON INTO TONIGHT WITH SOME LARGER SCALE ASCENT INCREASING ACROSS THE SOUTHWEST MOUNTAINS FROM MID-MORNING INTO THE AFTERNOON HOURS. OVER THE EASTERN PORTION OF THE CWFA LARGE SCALE ASCENT DEVELOPS DURING THE AFTERNOON AND EVENING HOURS. CONTEMPLATED SNOW/BLOWING SNOW ADVISORY FOR SOME OF THE MOUNTAIN AREAS BUT WITH BEST LIFT SOUTH IN NEW MEXICO AND SNOW MODEL QUITE MEAGER IN PROJECTED SNOW AMOUNTS WILL JUST MENTION SNOW AMOUNTS UNDER ADVISORY CRITERIA. BEST POTENTIAL FOR ACCUMULATING SNOW OVER ZONES 60 AND 61 FROM LATER THIS MORNING INTO THE AFTERNOON WHILE HIGHEST CHANCE FOR MEASURABLE SNOW FOR ZONES 58 AND 59 FROM LATER THIS AFTERNOON INTO TONIGHT. MODELS ALL AGREE ON RATHER SIGNIFICANT COOL DOWN IN BOTH MAXIMUM AND MINIMUM TEMPERATURES TODAY/TONIGHT AND ESPECIALLY TOMORROW WITH TEMPERATURES ON MONDAY AT LEAST 20F COOLER THAN NOTED ON SATURDAY IN MANY AREAS. MONDAY SHOULD ALSO BE WINDY. ALSO ON MONDAY ETA INDICATES ANOTHER SHORTWAVE IN FAST NORTHWEST FLOW ALOFT TO MOVE ACROSS REGION FORCING MENTION OF CHANCE OF SNOW FOR AT LEAST ZONES 58 AND 59. WILL KEEP GOING EXTENDED AS IS WITH MINOR TEMPERATURE TWEAKS...EVEN THOUGH POPS LOOK MORE UNCERTAIN FOR THURSDAY. .PUB...NONE. "77" co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1005 PM EST SAT JAN 1 2000 FOCUS IS ON SNOW BEGINNING OVERNIGHT IN THE U.P. REMAINS OF CUTOFF LOW THAT WAS OFF SOUTHERN CALIFORNIA COAST LAST CENTURY IS REJOINING THE MEAN FLOW AND SHEARING OUT AS IT TRAVELS INTO CENTRAL CONUS TONIGHT. VORT MAX NOW DROPPING OUT OF THE ROCKIES IN EASTERN COLORADO...ASSOCIATED SURFACE LOW IS IN KANSAS WITH WARM FRONT EXTENDING NORTHEAST TO THE ILLINOIS/WISCONSIN BORDER. PRECIPITATION WITH THIS SYSTEM THUS FAR HAS BEEN VERY LIMITED...BUT OVER RUNNING PRECIPITATION WITH WARM FRONT IS PROGGED BY ALL MODELS TO INTENSIFY OVERNIGHT AS SEEN IN INCREASING 1000-500MB LAYER RH AND INCREASING ISENTROPIC LIFT. 1000-850MB THICKNESSES OF 1300M OR A BIT WARMER GRAZE THE SOUTHERN U.P. OVERNIGHT...BUT MODELS SHOW THE ENTIRE SOUNDING AT MNM BELOW FREEZING AT 06Z...AND THEN FAIL TO DEVELOP A SIGNIFICANT (OR ANY) ELEVATED ABOVE-FREEZING LAYER BY 12Z. CLOSE CALL...BUT WILL NOT INTRODUCE MENTION OF FREEZING RAIN FOR MNM TONIGHT. AGING 12Z MODELS HOLD OFF ON DEVELOPING PRECIPITATION IN THE U.P. UNTIL AFTER MIDNIGHT...AND LATEST MESOETA AND RUC MODELS SHOW THIS THEME AS WELL. WITH THIS EVENT YET TO REALLY GET UNDERWAY...WILL NOT MAKE ANY SIGNIFICANT CHANGES TO CURRENT FORECAST PACKAGE WHICH LOOKS ON TRACK. .MQT...SNOW ADVISORY OVERNIGHT AND SUNDAY MIZ005>007-010>014. ES mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 930 PM EST SAT JAN 1 2000 WAVE MOVING UP FRONT STRETCHED FROM IOWA THROUGH MICHIGAN WILL BRING PRECIPITATION OVERNIGHT. LITTLE CONCERNED WITH LACK OF PRECIPITATION UPSTREAM ESPECIALLY WITH STRONG UPWARD VERTICAL VELOCITIES. RIGHT ENTRANCE REGION DYNAMICS WITH ENHANCED LOW LEVEL JET PROVIDING STRONG LIFT WITH ENHANCEMENT FROM FRONTOGENETIC FORCING. VERY DRY AIR OVER IOWA AS PER KDVN SOUNDING. ATMOSPHERE LITTLE MORE MOIST AT KMPX AND CONTINUED LIFT SHOULD SATURATE LOW LEVELS EVENTUALLY. HOWEVER...MAY TAKE A WHILE. BEST LIFT IN RIGHT ENTRANCE REGION REACHES REGION AROUND 09Z...SO EXPECT PRECIPITATION TO START A COUPLE HOURS AFTER THAT. RUC/MESOETA SURFACE LOW POSITION VERY CLOSE BUT QPF VASTLY DIFFERENT. MESOETA SHOWS 0.25 IN QPF AT 06Z...WHILE RUC HAS NONE ACROSS WISCONSIN. RUC LOOKS BETTER SO FAR. IF PRECIPITATION STARTS BEFORE DAYBREAK...BASED ON MODEL SOUNDINGS...CURRENT FORECAST OF SOME FREEZING RAIN ACROSS NORTHERN LOWER/SNOW IN EASTERN UPPER LOOKS OK. CURRENT TEMPS IN THE LOW AND MID 30S ACROSS NORTHERN LOWER...AND EXPECT LITTLE DROP...BUT PRECIPITATION FALLING INTO "DRIER" LOW LEVELS COULD WETBULB THE TEMPERATURE TO AROUND 30. SO FREEZING RAIN POSSIBLE...BUT WARM WEATHER OF PAST COUPLE DAYS SHOULD KEEP ROADS WARM ENOUGH FOR LITTLE PROBLEMS. OTHER OBJECTS COULD COLLECT SOME ICE. FOR NOW WILL SAY NO CHANGES TO CURRENT ADVISORY BUT WOULD LIKE TO SEE PRECIPITATION DEVELOP TO OUR WEST BEFORE ISSUANCE. WILL HOLD UPDATE UNTIL AFTER 10 PM. ONLY OTHER CHANGES...UPDATED WIND AND TEMPERATURE WORDING. .APX...SNOW ADVISORY LATE TONIGHT AND SUNDAY...MIZ008-015. WINTER WEATHER ADVISORY LATE TONIGHT/EARLY SUNDAY... MIZ019-021>023-027>029. FARINA mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 330 AM CST SUN JAN 2 2000 STLT SHOWD COMPACT AND STILL RATHER STG UPR SYS LIFTING TWD NERN NEBR. AT 09Z THE COLDEST AREA OF THE BAROCLINIC LEAF SHOWD SIGNS OF SHRINKING/WRMING. MOST OF THE PCPN IN THE WRM ADVCTN ZONE AHD OF THE LEAF HAS SHIFTED NE OF FCST AREA BUT A NARROW BAND OF A MIX CONTD STILL TO OUR WEST. WL HAVE TO INCLUDE SOME MENTION OF PCPN YET EARLY THIS MORNING...MAINLY NRN ZONES. FEEL THAT PCPN ON SRN END OF BAROCLINIC LEAF WL WEAKEN...ALTHOUGH IT COULD MAKE IT AS FAR E AS LNK/BIE/OMA. OTRW IN SHORT TERM MAIN QUESTION IS TEMPS SRN ZONES AND WHETHER OR NOT LOW CLDS WL CLR OUT ACRS THE N AND HOW FAR S WL THEY GO THIS MORNING. LATEST RUC AND LAST NGTS ETA/NGM ALL TRY TO SHIFT LOW CLDS E DURING THE DAY WITH THE ETA THE SLOWEST OR LEAST AGGRESSIVE. WL LEAVE NERN AND EXTREME E CNTRL ZONES WITH THE MOST CLDS TDA AND TRIM TEMPS THERE. NW AND SRN ZONES SHOULD BE PTCLDY THIS AFTN WITH AVN/NGM COMP GOOD IN TEMPS. FOR TNGT/MON...MODELS RELATIVELY CLOSE IN FCST ALTHOUGH WL LEAN TWD AVN AS NGM SEEMS A LTL TOO WRM AND ETA DIDN/T DO THE BEST WITH MSTR FIELDS WITH THE CURRENT SYS. RELATIVELY STEEP LAPSE RATES AGAIN WL MOVE ACRS FCST AREA LATER TNGT WITH INCREASING QG FORCING AS NEXT SHRTWV TROF/MAX MOV INTO CNTRL PLAINS. SFC LOW TRACK AND QPF FCST FM AVN SUGGEST SOME ACCUMULATIONS OF SNOW PRBL SRN ZONES...MAINLY ON MON. FOR TNGT...WRM ADVCTN PCPN PSBLY CREEPING INTO WRN/SRN ZONES AS ISENTROPIC LIFT LOWERS PRES COND DEFICITS. CONVECTIVE PCPN WL PRBLY DVLP ALONG STALLING BNDRY MAINLY SE OF NEBR. MOST OF THE PCPN IN OAX CWA WL BE ACRS SRN ZONES ON MON AS BTR MID LVL QG FORCING AND LOW LVL FRONTOGENESIS SHIFTS OVR THAT AREA. HOWEVER...WL RAISE POPS AREA WIDE AS ATMOSPHERE BECOMES MORE DEEPLY SATURATED AS MID/UPR LVL THERMAL TROF APPROACHES AND SOME WK FORCING EVEN MOVS ACRS NRN ZONES. WL TRIM BACK MOST TEMPS ON MON WITH EXPECTED PCPN AND COLD ADVCTN AS SFC LOW DEEPENS. MODELS SHIFT SFC LOW E OF FCST AREA ALREADY BY 00Z TUE WITH UPR LOW ALSO POISED TO SHIFT E. WL WORD TUE FCST MAINLY DRY AS MOST PCPN SHOULD BE E. BYND THAT A SERIES OF SHORTWVS CONT TO TRACK ACRS U.S. ALTHOUGH POSITION WED AND THU WOULD KEEP PCPN CHCS PRETTY SMALL ACRS FCST AREA...WL NOT MAKE CHANGES TO EXTENDED THOSE PDS. .OMA...NONE CHERMOK ne AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 1000 PM CST SAT JAN 1 2000 DETEORIATING WEATHER APPEARS IF OFFING REMAINDER OF NIGHT AS SHORT/WV TROF OVR WRN HI PLNS FM SW SD INTO NE NM LIFTS NEWD. LATEST ETA AND AVBL RUC TRACK VORT CNTR FM SE CO AREA RAPIDLY NEWD INTO SE NEB BY ARND 02/12Z. CLOUD TOPS COOLING FM CO AND NW KS INTO SW AND CNTRL NEB ATTM WITH THIS FEATURE AREAL COVERAGE OF RADAR RETURNS INCREASING. FEEL ALTHOUGH LWR LEVELS OF ATMOSPHERE RELATIVELY DRY...POTENTIAL FOR PRECIPITATION INCREASING IN ERN NEB AND SW IA ESPCLY ALNG AND TO THE NORTH OF VORT TRACK. LWR LVL BAOCLINIC ZONE ALSO TIGHTNING WITH FRONTOGENESIS FM SFC LOW SW OF KHLC INTO SW IA. THIS BNDRY ALSO SHUD PROVIDE LIFT AS SDF LOW TRACKS INTO S CNTRL IA SUN MRNG. BASED ON 02/00Z SOUNDINGS ALNG WITH FORECAST THICKNESS AND H85 TEMPS... PRECIPITATION WILL BE IN THE FORM OF LIQUID UNTIL SUFFICIENT COOLING OCCURS LATER TNGT ESPCLY ACROSS AREAS OF NE NEB INTO W CNTRL IA. WITH SFC TEMPS IN UPPER 20S AND LOWER 30S...RISK FOR FZRAIN EXISTS. ZONES UPDATED TO REFLECT THESE FORECAST TRENDS. .OMA...NONE WIESE ne AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 245 PM CST SAT JAN 1 2000 FORECAST CHALLENGES -- PRECIPITATION TYPE AND CHANCES SYNOPSIS -- LATEST KOAX VWP AND FBY PROFILER SHOWING IMPRESSIVE WARM ADVECTION PATTERN...RESULTING IN A FEW SPRINKLES FALLING OUT OF THE MID LEVEL CLOUD DECK MOVING ACROSS THE AREA THIS AFTERNOON. FARTHER UPSTREAM...LATEST VISIBLE SATELLITE/LDS COMPOSITE SHOWED THE NEXT SHORTWAVE TO AFFECT THE AREA OVER THE FOUR CORNERS REGION WITH SOME CONVECTIVE ACTIVITY OBSERVED PER LDS DATA. MEANWHILE...18Z SURFACE ANALYSIS HAD PRIMARY SURFACE LOW LOCATED OVER ERN CO WITH A STATIONARY FRONT EXTENDING NEWD THRU SERN NEB AND INTO CNTRL IA. FORECAST -- SWRN U.S. SHORTWAVE FAIRLY IMPRESSIVE THIS MORNING AT 500 MB WITH A 12 DECAMETER HEIGHT FALL OBSERVED AT FGZ. HOWEVER...ALL SHORT RANGE MODELS ARE CONSISTENT IN SHEARING OUT AND WEAKENING THIS FEATURE AS IT LIFTS NEWD THROUGH THE CWFA OVERNIGHT. IN THE SHORT TERM...LOW TO MID-LEVEL WARM ADVECTION REGIME TO SHIFT E OF THE AREA THIS EVENING WITH LARGE SCALE FORCING THEN DEPENDENT ON AMOUNT OF DPVA ASSOCIATED WITH THIS SYSTEM. Q-VECTOR AND MODEL OMEGA FIELDS SUGGEST ONLY MODEST UVV OVER ERN NEB/SWRN IA BY MIDNIGHT WITH MID LEVEL LAPSE RATES STEEPENING TO 7.5-8 DEG C/KM. THIS WOULD SUGGEST THAT THERE IS A CONTINUED CHANCE SPRINKLES OR FLURRIES OVERNIGHT... BUT THE RUC...ETA AND NGM ALL INDICATE THAT MID AND UPPER LEVEL DRYING WILL OCCUR ACROSS SERN NEB/SWRN IA OVERNIGHT. THEREFORE... THE BEST CHANCE OF ANY CONTINUED PRECIPITATION WOULD BE ACROSS THE NRN ZONES. COORD WITH GID AND WILL LEAVE SRN ZONES DRY WITH A MENTION OF SPRINKLES OR FLURRIES ACROSS THE N. SUNDAY...SUBSIDENCE ON BACKSIDE OF THIS EVENING'S SHORTWAVE WILL DECREASE THE CLOUDINESS...BUT LOW LEVEL COLD ADVECTION SHOULD DROP TEMPERATURES SLIGHTLY...ESPECIALLY ACROSS THE SRN ZONES WHERE READINGS ARE IN THE MID 50S THIS AFTERNOON. BY SUNDAY NIGHT...THE NEXT IN A SERIES OF SHORTWAVES MOVES OUT OF THE ROCKIES WITH A SURFACE LOW REDEVELOPING OVER CNTRL KS. MODEL OMEGA AND Q-VECTOR FIELDS ARE MUCH MORE IMPRESSIVE WITH THIS SYSTEM AND AVN TIME SECTIONS SUGGEST THAT THERE WILL BE BETTER DEEP-LAYERED MOISTURE TO WORK WITH. THE BEST CHANCE OF LIGHT SNOW OVERNIGHT WILL BE IN THE SWRN ZONES AND WE HAVE INSERTED 30 PERCENT POPS THERE. ELSEWHERE...SLIGHT CHANCE POPS HAVE BEEN PLACED ACROSS NWRN ZONES WITH A DRY FORECAST IN THE E. MONDAY...THE SURFACE LOW AND ASSOCIATED UPPER LEVEL SYSTEM LIFT NEWD INTO CNTRL MO WITH LARGE SCALE FORCING STILL IMPRESSIVE ACROSS THE SRN CWFA. THE AVN INDICATES THAT SPECIFIC HUMIDITIES OF 2 TO 3 G/KM WILL BE WRAPPED AROUND THE NORTH SIDE OF THIS SYSTEM...SO SOME ACCUMULATING SNOWFALL IS POSSIBLE...ESPECIALLY ACROSS SERN NEB. DUE TO UNCERTAINTIES IN TIMING AND LOCATION OF SYSTEM...WE WILL ONLY MENTION 40 PERCENT CHANCE POPS ACROSS THE S AND 20 PERCENT IN THE N. TEMPERATURES SHOULD BE CLOSER TO THE COOLER FWC NUMBERS ON HIGHS. IN THE EXTENDED...THE MRF ADVERTISES A CONTINUED ACTIVE PATTERN THROUGH NEXT WEEK WITH A CHANCE OF LIGHT SNOW ALL DAYS AND A RETURN TO MORE SEASONAL TEMPERATURES. .OMA...NONE MEAD ne AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORMAN OK 918 PM CST SAT JAN 1 2000 MOST NOTICEABLE CHANGE IN THE WEATHER ACROSS THE FORECAST AREA THIS EVENING IS THE RAPID INCREASE IN SURFACE MOISTURE WITH LOW TO MID 50 DEWPOINTS ALREADY INTO MUCH OF SOUTH CENTRAL OKLAHOMA. 12Z GUIDANCE DID NOT PICK UP ON THIS RAPID INCREASE VERY WELL AND THUS WILL NEED TO RAISE MINIMUM TEMPERATURES OVERNIGHT ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. STRATUS ALSO EXISTS ACROSS SOUTHEAST TEXAS PER SURFACE OBS AND SATELLITE IMAGERY. RECENT RUC2 GUIDANCE ADVECTS/DEVELOPS THIS STRATUS FARTHER NORTH OVERNIGHT...REACHING SOUTHEAST PORTIONS OF THE FORECAST AREA BY MIDNIGHT. DON'T BELIEVE THE STRATUS WILL BE HERE THAT FAST...BUT DO BELIEVE IT WILL EVENTUALLY MAKE IT...SO WILL MENTION BECOMING MOSTLY CLOUDY FOR EXTREME SOUTHEAST OKLAHOMA. OTHERWISE BELIEVE 00Z SURFACE AND UPPER AIR ANALYSES CONFIRM 12Z GUIDANCE. COLD FRONT CURRENTLY OVER THE OKLAHOMA/TEXAS PANHANDLES WILL MOVE EAST OVERNIGHT AS A STRONG SHORTWAVE OVER COLORADO NUDGES EASTWARD IN RESPONSE TO A DIGGING SHORTWAVE ACROSS THE WEST COAST. SURFACE WINDS WILL VEER GRADUALLY OVERNIGHT ALLOWING COOLER/DRIER AIR TO MOVE OVER THE FORECAST AREA...BUT MOST NOTICEABLE IN THE WEST. .OUN... OK...NONE. TX...NONE. JAMES ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BINGHAMTON NY 944 AM EST SUN JAN 2 2000 FINER RESOLUTION OF ETA MDL (PARTICULARLY PROGGED SOUNDINGS) ABSOLUTELY DRILLED THE FCST LAST SVRL CYCLES BY DEPICTING THE SHARP RADIATIVE AND WAA INVERSION AND PCP THIS AM. GLAD I WAS WITH IT. -RA SLIDING THRU AREA WITH A FEW COOP TEMP REPORTS CHECKING IN 28-32 DEG THIS MORNING AND A COUPLE REPORTS OF LIGHT GLAZING IN VALLEYS. FZRA WAS IN FCST SINCE FRI...BUT WITH TEMPS WARMING NICELY NOW WL REMOVE ALL MENTION AS WE GET ESTABLISHED IN WARM SECTOR TAFTN. RUC AND 06Z ETA ALL SHOW -SHRA TO LIFT NORTH TDY WITH UPSTRM RADARS MAINLY DRY ATTM. PROBLY STILL A SMALL CHC FOR SPRINKLES OR A SHOWER FROM WK FORCING BY THE MOIST CONVEYOR...ESPECIALLY LATER TAFTN AS LOW SHEARS OUT ALONG THE ST LAWRENCE AND CONVG ASSOC WITH LLJ PUNCHES INTO RGN. OVC CONDITS DIDN'T SEEM TO BE A PROB HOLDING BACK MAX T'S UPSTREAM YDY UNDER THIS MASSIVE WAA REGIME. CURRENTS A LTL BEHIND MOS/LAMP DATA...BUT WL CONTINUE LOW 50S FCST MOST AREAS...AND 40S FCST ACRS SNOW COVERED NRN ONEIDA. THIS FCST WL BE CLOSE TO RECORDS AS BGM 52...SYR 53 AND AVP 58 ON THIS DATE. COOP RECORDS VRY SIMILAR. WL BACK OFF ON WINDS SOME MORE WITH STRONG INVERSION AND CORE OF LLJ EXPECTED TWD 00Z. .BGM...NONE. BREWSTER ny SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA 930 AM PST SUN JAN 2 2000 CNSDRBL CLDNS AND PERHAPS EVEN A SHWR OR TWO CONT OVR LA CNTY MTNS ATTM...OTRW JUST SCT SC OVR MOST OF CWA. W WNDS GUSTG TO 25 KT OVR LA BASIN THIS MRNG BUT RMNDR OF CSTL AREAS RPRTG LGT WNDS. VLYS ALSO HV MSTLY LGT WNDS BUT BGNG TO GUST INTO 25-35 MPH RNG BLO PASSES...LA CNTY ONLY SO FAR. A FEW OF WNDY MTN LCTNS ALSO GUSTG TO ADV LVLS. NLY GRADS CONT TO INCR AND 24 HR PRES CHG INDICATES THIS WILL CONT. RUC INDICATES INCRG H8 WNDS TDA AND...AS LO LVL WNDS MIX DOWN TO SFC...XPC WNDS IN VLYS TO RCH ADV CRITERIA. SO WILL CONT WND ADV FOR MTNS TDA AND ISSUE ADV FOR VLYS VTU/LA CNTY BLO PASSES. RMNDR OF FCST LUKS OK. LAX 000. HENDERSON .LAX...SMALL CRAFT ADVISORIES (SEE LAXCWFLAX) WIND ADVISORIES (SEE LAXNPWLAX). ca AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE DES MOINES IA 935 AM CST SUN JAN 02 2000 UPDATED A WHILE AGO TO REMOVE PCPN IN ALL BUT NRN ZNS. STLT IMAGERY SHOWS SHRT WV CROSSING MO RVR WITH ASSOCD PCPN PUSHING RPDLY NEWD. EXTRAPOLATION OF DMX RADAR WOULD END MEASUREABLE PCPN NR KMCW BTWN 16-17Z. STILL PLENTY OF LOW LVL MSTR LEFT BHND HWVR SO COULD SEE A FEW FLURRIES OR LGT FRZG DRZL FOR AN HR OR SO AFT THAT TIME. CLOUDS FOR RMNDR OF DAY NEXT CONCERN. 12Z RUC KEEPS MSTR IN LOW LVLS THRU DAY SO KEPT SKIES CLOUDY. TRAJECTORIES BASED ON 925 MB PROFILER WOULD KEEP STRATUS IN MOST ZNS BUT MAY SEE SOME CLRG IN WRN FA WHICH WILL BE ADDRESSED IN NEXT LATE MRNG UPDATE ONCE PCPN ENDS. QUITE THE TEMP GRADIENT ACRS FA AT 15Z WITH FNT ALG KCNC-KALO LN. NRLY 25 DEGREE CHG FM KEST-KOTM. FNT SHOULD PASS THRU ENTIRE FA SHRTLY WITH READINGS THRN NRLY STEADY IN UPPER 20S OR 30S INTO AFTN. 12Z RUC 1000-850MB COLD ADVCTN MAX IS E OF FA BY AFTN BUT WITH CLOUDS AND STILL WEAK CAA DO NOT XPC ANY REBOUND. .DSM...NONE SMALL ia NORTHEAST MONTANA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 916 AM MST SUN JAN 2 2000 UPDATE PLANNED. BAND OF LT SNOW ACROSS W HALF OF CWA EXTENDING S/WARD TO VCNTY KBIL PROPTED LATE UPDATE BY PREV SHIFT. ARCTIC FRONT HAS BACKED W/WARD ACROSS E MT TO VCNTY CTB/GTF/BIL WITH WK CLIPPER XTRM SEMONT VCNTY BROADUS...SNOWBAND ABOUT WHERE WOULD XPCT OVERRUNNING. 12Z ETA/14Z RUC NOT HANDLING PATTERN ESP WELL...BUT DO SHOW AREA OF ISENTROPIC LIFT AND PRECIP ACROSS CNTRL MT INTO SW SASK AND SEMONT. 12Z NGM DOING SLIGHTLY BETTER WITH OMEGA FIELD AND PRECIP ACROSS NEMONT BUT NOT LINING UP WELL WITH OTHER FEATURES. UPDATED ZONES HANDLE CURRENT WX NICELY BUT CONCERNED ABOUT TRACK OF NEXT UPSTREAM VORT TIMED FOR THIS EVENING AND POTENTIAL FOR ADDITONAL SNOW FROM OVERRUNNING IF CLIPPER TRACKS S OF CWA. WILL UPDATE TO CLEAN UP WORDO/S IN CURRENT ZONES BUT WILL MONITOR FOR POSSIBLE ADDITIONAL UPDATE AND ADVISORY. GGW +53 018/005/015 GDV 764 021/005/015 SECORA mt