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 NATIONAL WEATHER SERVICE QUAD CITIES IA IL 900 PM CST SUN JAN 2 2000 WILL ISSUE UPDATE SHORTLY TO TWEAK TMPS ACROSS NRN SCTN OF CWA DOWN A FEW DEGREES. NARROW BAND OF CLEARING WORKING ITS WAY SOUTH ACRS NRN IWA SRN WI ATM SHLD MAKE IT INTO NRN SCTNS OF THE CWA ARND 06Z. WITH TMPS ALRDY A COUPLE OF DEGREES ABV FCST MINS...AN HOUR OR TWO OF CLEAR - PTCLDY CONDITIONS ALONG WITH LOW LVL CAA SHOULD BE ENUF TO LET TMPS COOL BLO CRNT FCST. CLRNG SHLDN'T LAST LONG WITH MVFR CIGS PUSHING SW ACRS NRN/CNTRL WI AND SRN MN IN NELY LOW LVL FLOW. WON'T MESS WITH CRNT HEADLINES ATM. STILL LKS GD FOR DECENT SNOW EVENT MON AFTN INTO TUE EVE. 12Z RUN OF ETA/AVN APRS TO BE VERIFYING REASONABLY WELL WITH RESPECT TO THE POSN OF DVLPNG DBL SFC LOW STRUCTURE OVR SERN CO AND W TX. 3HRLY PRES FALLS MAXES OVR OK PANHNDL AND NE TX ALSO LEND SUPPORT FOR ERLYR ETA/AVN RUNS FCST FOR 06Z POSN. QUEST AT THIS TIME IS PCPN TYPE AT THE ON SET AND IF IT STARTS AS LIQUID...HOW LONG WILL IT TAKE TO CHANGE OF SNOW. AT 00Z H8 ZERO ISOTHERM JUST W OF DVN. RUC DOESN'T CHANGE H8 TMP ON DVN SOUNDING MCH THROUGH MON MRNG. SO COLD AIR WILL BE VERY CLOSE... INDICATING IF EVENT STARTS AS RAIN...CHANGE OVER SHOULD BE RATHER EARLY IN THE EVENT. .DVN... IA...WINTER WEATHER ADVISORY PORTIONS MONDAY AFTERNOON AND NIGHT FOR PORTIONS EAST CENTRAL AND SOUTHEAST IOWA. IL...WINTER WEATHER ADVISORY PORTIONS MONDAY AFTERNOON AND NIGHT FOR PORTIONS NORTHWEST ILLINOIS. MO...NONE. FERRY il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 935 PM EST SUN JAN 2 2000 FRONT JUST NOW PASSING FWA AND EXTENDS TO WEST OF IND. ILX 00Z RAOB SHOWS DEEP DRYING AND DECENT LLVL NW FLOW WHICH SHOULD BE ENOUGH TO PUSH FRONT THROUGH AOH TNGT ESPECIALLY AFTER LWR OH VLLY SHRTWV MOVES NE. 00Z RUC ALSO SHOWS THIS SO WILL LOWER TMPS 2-3 CAT NW AND W AND 1-2 CAT E AND SE. FRONT WILL NOT BE TOO FAR AWAY AND AS NEXT SHRTWV QUICKLY MOVES NE TNGT FROM SRN PLAINS FRONT WILL MOVE NORTH AS SFC SYSTEM DEVELOPS. WILL LEAVE SCT SHWRS TIL MDNT AOH THEN BRING BACK LIKELY POPS TOWARD DAYBREAK. LIKELY POPS LATE SW ZNS AND WILL REMOVE POPS ELSEWHERE. WINDS TO SHIFT WNW THEN BECOME VARIABLE WITH WEAK GRAD BETWEEN SYSTEMS. NO CHANGES BEYOND FIRST PERIOD. .IWX...NONE. RES in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 840 PM CST SUN JAN 2 2000 FORECAST CONCERN NEAR TERM...CLOUD AND TEMPERATURE TRENDS. SATELLITE SHOWING DRY AIR INTRUSION FROM THE NORTHEAST. CLEAR AREA MOVING SOUTHWEST AND FILLING A BIT AS MOIST LOWER LAYER TAKES OVER. SOME FOG DEVELOPED IN SOUTH CENTRAL MN WHERE NEW SNOW MELTED DURING THE DAY. THIS SHOULD IMPROVE AS CLOUD LAYER ARRIVES AFTER MIDNIGHT. TEMPERATURES IN CLEAR AREAS ALREADY DROPPED WELL BELOW FORECAST VALUES...WILL TRIM THEM SOME. OTHERWISE...MOST OF THE CWA SHOULD REMAIN MOSTLY CLOUDY WITH HIGH CLOUDS NOW MOVING INTO WESTERN MN AHEAD OF WESTERN TROF. LATER PERIODS...APPEARS MODEL TRENDS OF ETA/AVN HAS BEEN TAKING NEXT STORM FARTHER SOUTH THAN PREVIOUS ONE. THIS VERIFIES RUC/ETA FORECAST USING MOISTURE CHANNEL THIS EVENING. THIS WOULD MAKE THE FAR SOUTHEAST MOST VULNERABLE. HOWEVER...VERY WEAK LIFT MOVING OVER THE STATE THROUGH MONDAY NIGH SHOULD CONTINUE THREAT OF VERY LIGHT SNOW OR FLURRIES. WILL LIKELY TRIM POPS A BIT. OTHERWISE...FORECAST LEFT AS IS FOR NOW. .MSP...NONE DWE mn SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 830 PM MST SUN JAN 2 2000 ...WILL UPDATE STATE AND TFX ZONE FORECASTS... ARCTIC HI IS PUSHING THRU N CENTRAL MT AND AGAINST E SLOPES OF THE ROCKIES. WTR VAPOR LOOP SHOWS APPARENT VORT CENTER RUC AND NEW ETA DRAG SE ALONG CONT DVD TONIGHT WITH SOME MOISTURE OVERRUNNING ARCTIC AMS. AT 03Z LIGHT SNOW FALLING AT MANY LOCATIONS...BUT WITH ARCTIC 3-4KT FT DEEP PER LATEST VWP DATA EXPECT ACCUMULATIONS TO GENERALLY BE LESS THAN 2 INCHES. CURRENT POP TREND LOOKS REASONABLE. AM MORE CONCERNED ABOUT TONIGHTS MIN TEMPS OVER NRN PORTIONS OF CWA. LOCATIONS ACROSS SRN ALTA ALREADY PUSHING -10 DEGF WHERE SKIES HAVE CLEARED. WILL UPDATE N CENTRAL MT FOR SOME CLEARING LATER TONIGHT AND COLDER TEMPS. EYSSAUTIER GTF 5311 HLN 6212 HVR 5411 mt 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 AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 1020 PM SUN JAN 2 2000 UPPER TROF IN SRN BRANCH BOTTOMING OUT ACROSS NM AND MOVING INTO W TX. TROF SHOULD START TO LIFT NEWD THRU THE OVERNITE. CLOUD TOPS COOLING RAPIDLY WITH DVLPG PRECIP ACROSS TX PNHDL THRU WRN OK INTO PTNS SRN KS AS DYNAMICS AND UVV WITH TROF TAKE HOLD. COLDER CLOUDS AHEAD OF SHORT/WV TROF IN NRN BRANCH FM ERN MT INTO WRN CO ALSO SPREADING ACROSS THE DKTS AND WRN THRU CNTRL WITH SOME PRECIP ALSO IN THIS AREA. QUICK LOOK AT ETA AND PREV RUC INDICATE LWR LVL WAA DVLPG ACROSS SHALLOWER COLD DOME ACROSS MUCH OF THE AREA BY MRNG. FEEL THIS COUPLED WITH THE APPROACH OF UPPER FORCING BY MRNG WARRANTS THE METION FOR CHC OF PRECIP BY MRNG ACROSS ALL OF CWFA. SOME CONCERN BASED ON RUC AND 03/00Z ETA THAT SNW/RN MIX PSBL PTNS OF SE NEB INTO SW IA TNGT INTO START OF MON. CONCERN EXISTS OVER SNOWFALL AMOUNTS WITH UPPER SYSTEM APPEARING QUITE INTENSE AND DYNAMIC ON STLT. COOK CONCEPT SHOWS ABOUT 12 DEGREE TEMP DIFFERCENCE BETWEEN WARM AND COLD POCKETS AT H2. BASED ON TRACK OF VORT CNTR ALONG WITH H7 AND H85 CENTERS AREAS OF SE NEB INTO SW IA APPEAR TO HV POTENTIAL FOR MST ACCUMULATION. HOWEVER BASED ON SPEED OF MVMNT AND SOME SHEARING AMNTS EXPECTED TO STAY UNDER HEAVY CRITERIA. ALSO CRITICAL TO FCST IS AFFECT OF NRN BRANCH SHORT/WV. 03/00Z ETA SHOWS THIS TO BECOME MORE DOMINANT SYSTEM DEFLECTING SPEEDING THE SRN BRANCH SHORT/WV. .OMA...NONE WIESE ne AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ALBUQUERQUE NM 300 PM MST SUN JAN 2 2000 VORT MAX HEADING INTO SWRN CRNR OF NM THIS AFTN WITH ANOTHER MAX ASSOCIATED WITH STG NWLY JET STREAK PUNCHING DOWN THROUGH NORTHCENTRAL AZ. 88D SHOWS WIDESPREAD PRECIP OVER WESTCENTRAL NM AND LESS WIDESPREAD COVERAGE NEAR SOUTHERN SLOPES OF THE NORTHERN MOUNTAINS. SPARSE POPULATION WESTCENTRAL HAS MADE GROUND TRUTH HARD TO COME BY BUT HAVE MANAGED TO FIND A COUPLE OF FOLKS WITH AN INCH OR 2 THIS AFTN. SUSPECT SOME OF THE HIGHER ELEVATIONS HAVE DONE BETTER. DOWNSLOPE OFF CONTINENTAL DIVIDE HAS KEPT PRECIP FROM REACHING THE GROUND IN RIO GRANDE VALLEY. RUC INDICATES BEST PIVA AND HIGHEST RH ACROSS NORTH AND CENTRAL THIS EVENING. WILL KEEP THE FAITH AND CONTINUE SNOW ADVISORY FOR WESTCENTRAL AND NORTHERN MOUNTAINS...TAPERING OFF THIS EVENING IN WEST AND LATE TONIGHT OVER NORTH...THOUGH COULD STILL SEE SOME WRAPAROUND NORTHCENTRAL AND NORTHEAST TIL MID MORNING MON. WILL ALSO CONTINUE WIND ADVISORY SOUTHCENTRAL MOUNTAINS TIL LATE TONIGHT. WINDS HAVE BEEN MARGINAL BUT SHOULD PICK UP FOR A TIME AFTER PASSAGE OF FIRST VORT MAX. AFTER TONIGHT...EXPECT MODERATE TO STRONG NORTH TO NORTHWEST WINDS TO DEVELOP MONDAY MORNING NEAR AND EAST OF EAST SLOPES OF CENTRAL MOUNTAINS. WILL EMPHASIZE WINDS AND COLD MONDAY BUT LEAVE TO SUBSEQUENT FORECASTERS TO ISSUE ADVISORY IF THINGS STILL LOOK LIKE THEY ARE ON TRACK FOR THAT. MONDAY NIGHT SHOULD BE CLEAR AND COLD...WITH SOME WARMING TUESDAY AS RIDGING DEVELOPS AHEAD OF NEXT SHORTWAVE DROPPING IN FROM NORTHWEST. FOR EXTENDED...FLATTER TROUGH BRUSHING ACROSS NORTH WEDNESDAY FOR SOME CHANCE FOR MOUNTAIN SNOW SHOWERS. WARMING EAST AND SOUTH WEDNESDAY AHEAD OF WAVE...THEN COOLING THURSDAY AS SURFACE HIGH BUILDS IN. AIRMASS SHOULD NOT BE QUITE AS COLD AS ONE MOVING IN MONDAY WITH FLATTER MID LEVEL FLOW. TEMPS REBOUNDING A LITTLE FRIDAY. MJF ABQ BA 020/035 013/040 022 325-0 SAF BA 014/032 008/038 016 325-0 TCC BA 027/040 014/050 021 32-00 .ABQ...SNOW ADVISORY THIS AFTN/EVE NRN AND WRN MTNS(ZNS 2,4,,8,14) WIND ADVISORY THIS AFTN/EVE SCNTRL MTNS (ZNS 16,17,26) nm EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 725 PM CST SUN JAN 2 2000 UPDATING FCST AS TEMPS DROPPING FAST NORTH OF WARM FRONT/ NORTHERN EDGE OF RICH MOISTURE LOCATED AT 7 PM FROM ARDMORE TO MUSKOGEE TO FAYETTEVILLE. ALREADY 36 AT KBVO...45 AT KFYV...AND 40 AT KRVS (JENKS RIVERSIDE). ALTHOUGH THESE SITES OFTEN COOL RAPIDLY ON CALM DRY NIGHTS OTHER MESONET SITES ALSO COOLING QUICKLY. SOUTH OF THE FRONT...TEMPS LOOK GOOD. ABOUT POPS...KEPT THEM MOSTLY UNCHANGED. LOWERED THEM SLIGHTLY FOR THE EVENING PERIOD AND REMOVED MENTION OF SVR IN SE OK. LATEST MCD AND DY1 OUTLOOK NOT SHOWING MUCH RISK OF SVR UNTIL AFTER MIDNIGHT WITH ONLY SLIGHT RISK. WE USUALLY DO NOT MENTION SVR IN TEXT FORECASTS UNLESS CONVECTIVE WATCH IS IN EFFECT OR SIGNIFICANT SVR EXPECTED. IF HIGH WIND THREAT INCREASES LATER TONIGHT IN SE OK/WC AR WILL REINTRODUCE MENTION OF SVR. UPR LOW CURRENTLY OVER NEW MEXICO AND LOOKS A LITTLE FURTHER NORTH THAN 12 MODELS AND EVEN 21Z RUC BASED ON WV AND PROFILERS. TIMING ABOUT THE SAME SO WILL KEEP POPS ABOUT WHERE THEY ARE. FCSTID = 26 .TUL... AR...NONE. OK...NONE. ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 304 PM CST SUN JAN 2 2000 FCST FOCUS ON SYSTEM MOVG UP FM SRN PLAINS FOR MON NGT AND TUE. IN THE SHORT TERM...SHRT WV AND ASSOC VORT MAX SHEARING OUT AS EXIT WI. FCST ETA H3 DIVERGENCE FIELD FM 12Z WELL IN LINE WITH PCPN MOVG ACROSS NRN WI. LO CLDS AND FOG ARE MOVG SWD ACROSS CWA IN WAKE OF SFC LO...AS CAA WILL DROP TEMPS FROM RECORD READINGS. SWD MOVEMENT OF COLDER AIR AND RESULTANT SFC/MID LVL BNDRY WL BE CRITICAL FOR STORM TRACK FOR LT MON INTO TUE. IN THE LONGER TERM...MODELS DIFFER IN HANDLING NEXT SYSTEM MOVG OUT OF SRN PLAINS. ETA INITIALLY FASTER AND FARTHER SOUTH WITH MID LVL CIRCULATION AND H8 BAROCLININC ZN. AVN SLOWS AFTR 36HRS WITH H8 LO OVR CHI AT 06Z TUE...WITH ETA/NGM H8 CIRCULATION ALREADY IN CNTL/NRN LWR MI RESPECTIVELY BY 06Z. PREFER FASTER SLN AS H5 TROF REMAINS OPEN AND MORE PROGRESSIVE. FEEL NGM IS TOO DEEP WITH H5 HGTS. 12 ETA AND 18Z RUC H5 HGT FIELDS MATCHING WELL AND WL FOLLOW MORE TWD ETA/AVN SLN. MAIN PUSH OF MOISTURE OVR SRN WI WL BE BETWEEN 18Z MON AND 12Z TUE. 290K ISEN CHRTS HAV WRN AREAS INTO SINKING MOTION AFT 06Z TUE... SPREADING TO THE EAST BY 12Z TUE. LOOKING FOR LO CLDS AND FLURRIES IN CAA AFTER 12Z TUE. NEXT QUESTION BECOMES PCPN TYPE OVR CWA. THKNS PROGS WUD KP MIX OVR SE CRNR UNTIL BETWEEN 00Z-06Z...WITH ETA AND AVN HAVG THE REST OF THE CWA ALL SNOW. NGM PROGS PLACE 540DM LINE SO THAT AREAS NW OF A MTW TO DBQ WL SEE SNOW...AND POINTS SE OF THE LINE A MIX THRU 06Z. FCST SNDGS FAVOR THE COOLER ETA AND AVN SNDGS...WITH THE NGM 850- 800 MB WRM LYR GONE BY 06Z IN THE EAST...AND NEVER GOING ABOVE 0C. WL GET ACCUMULATING SNOW IN CWA...WITH THE WESTERN HALF SEEING ALL SNOW STARTING LATE IN THE AFTERNOON. THERE WILL BE RAIN OR A RAIN/SNOW MIX IN THE EAST TO START...ESPECIALLY WITH STG EASTERLY WINDS OFF THE LAKE KPG SFC TEMPS UP A BIT...THEN CHNG TO SNOW MON EVE. WL MENTION SOME 2-5 INCH POSSIBLE ACCUMULATIONS IN SRN PORTIONS OF CWA...AND WITH UNCERTAINTY OVR EXACT TRACK OF SFC/MID LVL LOWS AND WIDE VARIATION OVR AVAILABLE MOISTURE IN THE MODELS...WILL NOT ISSUE HEADLINES AT THIS TIME. WL LEAN TWD FAN TEMPS FOR THE ERLY PDS AND COOLER FWC TEMPS LATE. THANKS TO DVN...LOT...ARX AND GRB FOR COORDINATION. .UWNMS...NOT AVBL. .MKX...NONE. //...0.../.../ REM wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 210 AM EST MON JAN 3 2000 WILL BE UPDATING ZONES FOR CLOUDS...TEMPERATURES...WINDS...AND WEATHER OVERNIGHT. SATELLITE STRATUS PRODUCT SHOWS LOW LEVEL CLOUDS REACHING FAR SOUTHEAST NOW...AS CLEARING EVIDENT ACROSS SAGINAW VALLEY. SAGINAW VALLEY CLEARING IS ISOLATED...WITH CLOUDS FILLING IN BEHIND CLEARING AREA AS IT MOVES SOUTH. WILL TWEAK CLOUD COVER ACROSS SAGINAW VALLEY FROM CLOUDY TO MOSTLY CLOUDY TO ACCOUNT FOR CLEARING. TEMPERATURES ACROSS NORTHERN CWA HAVE FALLEN TO NEAR FORECAST LOWS FOR THE OVERNIGHT PERIOD. WILL LOWER FORECAST MINS ALL ZONES FOR THE OVERNIGHT. WINDS ARE NOW NORTHERLY ACROSS MOST OF CWA...EXCEPT FAR SOUTHEAST WHERE QUICKLY COMING AROUND TO NORTHWEST. SO WILL DROP MENTION OF WEST WINDS ALL ZONES IN LIEU OF NORTH WINDS...EXCEPT FAR SOUTH WHERE WILL OPT FOR NORTHWEST. FINALLY WILL DROP MENTION OF DRIZZLE OVERNIGHT ALL ZONES. SURFACE OBS AND RUC SOUNDINGS DO NOT SUPPORT DRIZZLE. NOT QUITE CONVINCED WE/LL SEE ANY FOG EITHER. BUT...SHOULD CLEARING LINGER...AND WINDS DROP OFF...NOT OUT OF THE QUESTION FOG COULD DEVELOP. SO WILL KEEP MENTION OF PATCHY FOG IN ZONES. .DTX...NONE. OKEEFE mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1030 PM EST SUN JAN 2 2000 01Z SFC ANALYSIS SHOWS MAIN 1000MB LOW OVER SE ONTARIO AND 1026MB HIGH NEAR LAKE WINNIPEG. RECENT METARS HAVE BEEN SHOWING A DOWNWARD TREND IN NORTHERLY WIND SPEEDS ACROSS THE CWA AS PRESSURE GRADIENT RELAXES. 88D SHOWING NO ECHOES ACROSS UPR MI. UPSTREAM 00Z SOUNDING AT KINL SHOWS BASE OF SUBSIDENCE INVERSION AT 850MB. KMPX SOUNDING SIMILAR...EXCEPT INVERSION SLIGHTLY LOWER AND LOW LAYER (1000-900MB) IS A LITTLE DRIER. LOW LEVEL MOISTURE ALSO QUITE EVIDENT ON 11-3.9 MICRON IMAGERY...WHICH SHOWS WIDESPREAD LOW CLOUDS. REGIONAL METARS SHOWING CIGS 010-020...AND BLO 010 OVER SEVERAL STATIONS IN UPR. LOW CLOUDS OVER THE CWA BEING ENHANCED BY ONSHORE FLOW AND 850MB/LAKE DELTA/TS AROUND 10C. HAVE ALSO HAD PERSISTENT FLURRIES HERE AT THE OFFICE. RUC HAS GOOD HANDLE ON SFC FEATURES AND THERMAL FIELDS...SO FOLLOWED RUC FOR OVERNIGHT DETAILS. HIGH PRESSURE WILL CONTINUE TO TRY TO BUILD IN FROM THE N AS THE SFC LOW OVER SE ONTARIO CONTINUES MOVING OFF TO THE NE. FORECAST SOUNDINGS SHOW INVERSION LOWERING TO AROUND 950MB WESTERN COUNTIES...900MB CNTRL...AND TO THE SFC EAST. 00Z ETA SOUNDING ALSO SHOWS SOME DRYING OCCURRING AT THE SFC IN THE EAST. WILL LEAVE WORDING OF MOSTLY CLOUDY SKIES SINCE I'M NOT CONVINCED THE LOW CLOUDS WILL GIVE WAY. MODELS SEEM TO TRY TO LOWER INVERSION LEVELS TOO QUICKLY AND COMPONENT COMING OFF THE LAKE WILL SUPPORT LOW CLOUDS. WILL ALSO MAINTAIN WORDING OF EARLY SCATTERED FLURRIES FOR MQT GIVEN OBS HERE...UPSLOPE FLOW...AND MOIST LOW LEVELS. OTHERWISE...ALREADY DID QUICK UPDATE AT 7 PM WHEN WINTER STORM WARNING EXPIRED THIS EVENING...SO WILL MAINLY FRESHEN WORDING. WILL ALSO TRIM WINDS A LITTLE BASED ON CURRENT OBS. .MQT...NONE. JS mi AREA FORECAST DISCUSSION...CORRECTED WORDING NATIONAL WEATHER SERVICE JACKSON MS 900 PM CST SUN JAN 2 2000 GOOD STREAM OF MOISTURE AT BOTH UPPER/LOWER LEVELS FROM SUB-TROPICAL JET AND VERY STRONG LLJ OFF THE GULF WILL RESULT IN PLENTY OF MOISTURE/CLOUDS AS NOTED ON FOG IR PRODUCT. THE INCREASING STRATUS OVERNIGHT AND STRONG LLJ WILL HOLD SLY WINDS IN THE 10-20 MPH RANGE MOST PLACES AS SURFACE LOW DEVELOPS AND DEEPENS OVER OKLAHOMA OVERNIGHT. THE WINDS AND DEW PTS GENERALLY AROUND 60 DEG F WILL HOLD LOWS IN THE 60S FOR THE MOST PART. UPDATING NW ZONES LOWS WITH CURRENT SCENERIO AND WILL EASE WINDS DOWN A TAD ALL ZONES WITH INCREASING STRATUS. OTHERWISE...CONVECTION OCCURRING ALONG WARM FRONT FROM NE TEXAS INTO CENTRAL ARKANSAS WILL STAY NORTH OF OUR FA UNTIL AFTER 12Z MON PER MESO-ETA/RUC DUE TO BACKING WINDS WITH DEEPENING SURFACE LOW OVER THE SRN PLAINS. JUST A FEW SPRINKLES OVERNIGHT AS DYNAMICS STAY WELL WEST OF FA THROUGH 12Z. ON MONDAY...MODERATE RISK OVER NW FA WITH SLIGHT RISK EXTENDING AS FAR EAST AS MERIDIAN-MCCOMB LINE PER SPC. THIS SEEMS VERY REASONABLE WITH GOOD LOW LEVEL MOISTURE...VERTICAL SPEED SHEAR AND STRONG LIFT COMBINING FOR A VERY UNSTABLE REGIME AS SRN PLAINS VORT MAX APPROACHES THE FA. NEXT THUNDERSTORM OUTLOOK WILL BE ISSUED AROUND 10Z MON. .JAN... MS...NONE. AR...NONE. LA...NONE. 05 ms AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE JACKSON MS 900 PM CST SUN JAN 2 2000 GOOD STREAM OF MOISTURE AT BOTH UPPER/LOWER LEVELS FROM SUB-TROPICAL JET AND VERY STRONG LLJ OFF THE GULF RESULT IN PLENTY OF MOISTURE/CLOUDS AS NOTED ON FOG IR PRODUCT. THE INCREASING STRATUS OVERNIGHT STRONG LLJ WILL HOLD SLY WINDS IN THE 10-20 MPH RANGE MOST PLACES AS SURFACE LOW DEVELOPS AND DEEPENS OVER OKLAHOMA OVERNIGHT. THE WINDS AND DEW PTS GENERALLY AROUND 60 DEG F WILL HOLD LOWS IN THE 60S FOR THE MOST PART. UPDATING NW ZONES LOWS WITH CURRENT SCENERIO AND WILL EASE WINDS DOWN A TAD ALL ZONES WITH INCREASING STRATUS. OTHERWISE...CONVECTION OCCURRING ALONG WARM FRONT FROM NE TEXAS INTO CENTRAL ARKANSAS WILL STAY NORTH OF OUR FA UNTIL AFTER 12Z MON PER MESO-ETA/RUC DUE TO BACKING WINDS WITH DEEPENING SURFACE LOW OVER THE SRN PLAINS. JUST A FEW SPRINKLES OVERNIGHT AS DYNAMICS STAY WELL WEST OF FA THROUGH 12Z. ON MONDAY...MODERATE RISK OVER NW FA WITH SLIGHT RISK EXTENDING AS FAR EAST AS MERIDIAN-MCCOMB LINE PER SPC. THIS SEEMS VERY REASONABLE WITH GOOD LOW LEVEL MOISTURE...VERTICAL SPEED SHEAR AND STRONG LIFT COMBINING FOR A VERY UNSTABLE REGIME AS SRN PLAINS VORT MAX APPROACHES THE FA. NEXT THUNDERSTORM OUTLOOK WILL BE ISSUED AROUND 10Z MON. .JAN... MS...NONE. AR...NONE. LA...NONE. 05 ms AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 448 AM CST MON JAN 3 2000 PESKY LITTLE SOUTHWEST LOW TAKING AIM ON CWA TDY. SFC DEEPENING OVR CNTL OK LAST FEW HRS WITH QUITE A BIT OF CNVTN ACR ERN OK NOSING INTO XTRM SW MO. THIS CNVTN APPRS TO BE FUELED BY DVRGNC AND 125 KT JET AT H3. EAX 88-D ALREADY BANGING SOME MID LVL RETURNS WITH THIS FEATURE SO XPCT ISOLD PCPN TO DVLP ARND DAYBRK. INTITIALLY SOUNDINGS SUGGEST PCPN BEGINNING AS -RA HOWEVER WITH LWR TROPOSPHERIC WET BULBS IN UPR 20S THINK THAT ALL -SN SHLD FALL IF ANY LIFT OF SIGNIFICANCE OCCURS. WORDED ALL ZNS TO READ PSBL -RA AT OUTSET THEN ALL -SN THROUGHOUT THE DAY. ALL MODELS LIFT THIS UPR LVL DVRGNC TO N OF FCST AREA BY 1800 UTC. BET 1800 UTC AND 0600 UTC MODELS FCST WEAK DEFORMATION ZN TO TRACK ACR CWA. AREA OF -SN SHOWING UP ON RADAR ATTM ACR S CNTL KS. PCPN APPRS TO BE LGT AND NOT VRY ORGANIZED ATTM HOWEVER AS SYS MVS FTHR N INTO BETTER BAROCLINIC ENVIRONMENT WOULD NOT BE SURPRISED TO SEE BETTER ENHANCEMENT. LATEST RUNS ETA/NGM AND RUC ALL SUGGEST STG ISENTROPIC LIFT IN 6 HR PRD BET 1800-2400 UTC ALG WITH SHALLOW LYR OF CSI JUST ABV H8. ALG XTRM SE PERIPHERY OF CWA ETA CROS SECT SHOWED WEAK ELEVATED CNVTN POT. ETA/NGM/RUC ALL BRING QUITE A BIT OF WATER NWRD WITH 4.0 GM/KG SPEC HUMIDITIES FCST TO PUNCH INTO RGN THIS PM. THINK THAT THIS WILL BE A SHORT LIVED EVENT ALG MAGNITUDE OF 6 HRS OR SO. VARIOUS EMPIRACLE RULES SUGGEST MAXIMUM POT SNOWFALL IN 6-7 INCH NEIGHBORHOOD. HOWEVER BASED ON QUICK FCST MVMNT AND LACK OF STG CNVGNC OF Q/QN OVR CWA AND NOT MUCH BETTER THAN STANDARD 10:1 RATIO XPTD DUE TO MOIST ENVIRONMENT WITH TEMPS NR OR JUST UNDR FRZG ISSUED SN ADVSY ALG MKC-IRK CORREDOR FOR 3-5 INCHES. STG CAA IN LWR TROPOSPHERE FCST THROUGHOUT THE DAY SUGGEST LTL OR NO TEMP RISE TDY SO WORDED TEMPS STEADY OF FALLING ALL ZNS. STAYED FAIRLY CLOSE TO GUIDANCE NUMBERS THRU FCST PRD XCPT FOR TUE NITE WENT SVRL CATS UNDR DUE TO XPCTD CLR SKIES AND FRESH SN CVR. HAD NO TIME TO LK AT XTND SO LEFT IN TACT. THANKS TOP/LSX/SGF/DMX/MLI FOR COORDINATION. .EAX... KS...SNOW ADVISORY FOR MONDAY FOR ZONES KSZ057...KSZ103>105. MO...SNOW ADVISORY FOR MONDAY FOR ZONES MOZ021>022...MOZ028>030... MOZ037>038...MOZ043>044. SNOW ADVISORY FOR THIS AFTERNOON THROUGH LATE TONIGHT FOR ZONES MOZ005>008...MOZ014>017...MOZ023>025...MOZ031>032. BODNER mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 330 AM MON JAN 3 2000 ...FORECAST CHALLENGES...CHC OF PRECIP/TYPE/AMOUNTS/WNDS. ...SYNOPSIS...SFC FNT THAT PUSHED OUT OF THE AREA...IS WELL TO THE S OVR SRN OK AND NRN AK. LO CLDS AND FOG SETTLED IN WITH A VARIETY OF WX BEING REPORTED FROM FREEZING MIST...TO FLURRIES TO DRIZZLE ACROSS THE AREA. TEMPS RANGED FM THE UPR 20S TO THE LOWER 30S AND WE ARE AROUND 30 AT THE STATION IN VALLEY. ...FORECAST...THE MODELS ARE VERY SIMILAR...TRACKING THE SHRTWV FM TX NE TO MO BY 00Z. THE 700 MB LO TRACKS FM SW KS TO MKC AND SE IA...WHILE THE 850 MB LO POSITION IS JUST SE OF THIS TRACK. ALL THREE MODELS GENERATE ONLY -SN FOR THE FA...WITH THE ETA .08 WATER EQUIV AND THE NGM FAILS TO ACCUM AT OMA. SOME CONCERN DESPITE FAST MOVEMENT OF SYSTEM...AS THE LFQ OF THE JET AFFECTS SE NEB AND STEEP LAPSE RATES COULD GENERATE A QUICK COUPLE OF INCHES. 850 MB TEMPS ARE MARGINAL INITIALLY IN THE SE AND EVEN AT OFF THEY HAVE BEEN REPORTING A MIX WITH THE LIGHT PRECIP THERE. THE RUC HAS THE 850MB TEMPS COOLING BELOW ZERO AFT 15Z. THE BEST Q-VECTOR FORCING IS ALONG THE KS/NEB BORDER INTO SRN IA FM 18Z-06Z TON. THE UPR DIV CORRELATES WELL WITH THE ENHANCED CLDS OVR KS/OK AND MO THIS AM. THIS UPR LVL DIV RMNS S AND E OF MUCH OF THE FCST AREA DURING THE PD. DUE TO LO CLDS AND FOG...EXPECT TO RISK OF -FZDZ TO CONT UNTIL BETTER LIFT DEV LATER THIS MORNING FOR THE NRN TWO THIRDS OF THE FA. WILL INCLUDE PDS OF -SN WITH -FZDZ ERLY WITH LITTLE ACCUM. WILL MENTION AMOUNTS OF 1-3 IN SRN ZONES...STARTING AS RAIN...THEN QUICKLY CHGING TO SN. STG WNDS TO KICK IN THIS AFT AND CONTINUE OVERNIGHT. WILL MENTION BLOWING SNOW IN ZONES. FOR TEMPS...WILL COMPROMISE BETWEEN MODELS AS CCA INCREASES LATER THIS AM. NO SIG CHGS TO THE EXTENDED. COORD GID/EAX .OMA...NONE ZAPOTOCNY ne AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 1035 AM CST MON JAN 3 2000 INCREASING EASTERLY FLOW HAS BROUGHT WIDESPREAD SC FIELD ACROSS ZONE FORECAST AREA THIS MORNING. WEAK SFC TROUGH HAS NUDGED ITS WAY INTO FAR WEST WITH WIDESPREAD -SN ACRS ERN SD SPREADING INTO AREA. ETH REPORTING -SN FOR ABOUT 1 HR. WILL BE FIGHTING AGAINST DRY MID LEVELS AS WELL. ADDED MENTION OF -FZDZ DUE TO SAID DRYING. PRECURSOR S/W PUSHING RAPIDLY NE INTO IL HELPING TO SHARPEN/DEEPEN TROUGH OVR CENTRAL US. SECOND VIGOROUS S/W OVR KS/OK REGION. CIRCULATION APPEARS ABT 100 MILES FARTHER NORTH THAN INDICATED BY MODEL GUIDANCE PER EXAMINATION OF WIND PROFILER NETWORK. STILL MAIN FORCING SHOULD SKIRT SOUTHEAST OF ZONE FORECAST AREA. RUC 290 THETA SURFACE SHOWS CONDENSATION PRESSURE DEFICITS DECREASING TO LESS THAN 20MB OF LIFT OVR SOUTH CENTRAL ZFA THROUGH EARLY AFT AND SPREADS TWD EAU VCNTY IN AFTN. MUCH MORE SIGGY UPGLIDE AND MOISTENING FTHR SE OVR IL/WI. KMPX 88-D SHOWING LARGER AREA OF WEAK RETURNS DEVELOPING OVR IA/MN BORDER AND SPREADING NWD. CRITICAL THICKNESSES FAVOR SOLID PRECIP BUT 12Z SOUNDINGS MORE IN LN WITH POSSIBLE -FZRA/-FZDZ SCENARIO UNTIL BETTER FORCING OR EVAPORATIVE COOLING TAKES OVER. MUCH COLDER AIR ATTACHED TO MORE NWLY SFC WIND FLOW OVR WRN ZFA WITH UPSTREAM TEMPS ONLY IN THE SINGLE DIGITS AND TEENS. HENCE DO NOT EXPC MUCH RECOVERY IN DXX AREA TODAY. MOST LKLY WL NEED TO CARRY MENTION OF -SN MOST AREAS TONIGHT AS MID LEVEL TROUGH AND MOIST COLD AIR ADVECTION SPREADS ACRS AREA. .MSP...NONE KAVINSKY mn FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS 1020 AM CST MON JAN 3 2000 FCST CHALLENGE...TEMPS AND -SN THIS AFTN. ARCTIC FRONT HAS PUSHED THROUGH ALL OF ERN ND INTO SD...BUT STILL HAVING A HARD TIMING PUSHING EAST INTO THE HIGHER ELEVATIONS OF NW MN EAST OF THE VALLEY. TEMPS REMAIN IN THE MID TEENS TO LOWER 20S ROX-TVF-DTL-FFM EAST WHILE WEST THERE ARE IN THE SINGLE DIGITS. KMVX 88D SHOWING WIDESPREAD LIGHT SNOW OVER MUCH OF CWFA...EXCEPT FOR NW AND SE CORNERS. 88D RELFECTIVITIES SHOWING HEAVIEST SNOW (1-2 SM) NR A FAR-CKN-TVF LINE. OVERALL EXPECT UP TO AN INCH MAX IN SNOW AREA BY THE TIME IT ENDS. WHEN WILL IT END? WATER VAPOR AND 12Z ANALYSIS SHOWS 50H TROF STILL OVER WRN ND AND 12Z RUC AND LATEST ETA/NGM ALL IN GOOD AGREEMENT IN ONLY SLOWLY MOVING THIS EAST INTO THE VALLEY BY 00Z. ALSO SFC MAP SHOWS WK SFC TROF INTO CNTRL ND. THUS WILL KEEP FLURRIES DVL ZONE AND MENTION LIGHT SNOW OVER THE REST OF ERN ND AND WRN MN BEHIND ARCTIC FRONT THE REST OF THE DAY. SOME CLEARING OVER CNTRL ND MOVING INTO NW ZONES...BUT IT WILL BE PATCHY AND CLOUDS SHOULD PREVAIL. AS COLD AIR OOZES EAST INTO MN TEMPS WILL FALL IN THE DTL-FFM-TVF-BJI ZONES. OTHERWISE THEY WILL HOLD STEADY. UPDATE OUT BY 11 AM. .FGF...NONE. RIDDLE nd AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA NATIONAL WEATHER SERVICE ABERDEEN SD 1005 AM CST MON JAN 3 2000 MAIN CONCERN THIS MORNING IS WHEN WILL -FZDZ TURN OVER TO -SN. LOOKING AT MESO-ETA AND RUC MODEL SOUNDINGS...APPEARS THAT 850 TEMPS WERE SUFFECIENTLY WARM ENOUGH FOR THE ICE CRYSTALS NOT TO ACTIVATE..SO SUPER-COOLED WATER WAS ABUNDANCT. FORECAST SOUNDINGS SHOW THAT -9 TO -10 8H TEMPS ARE THE NECESSARY TEMPS FOR ICE TO ACTIVATE AND TURN WATER TO SNOW. THIS IS FORECAST TO HAPPEN BY 18Z ACROSS THE EASTERN CWA...AND ACCORDING TO CALLS PLACED TO VARIOUS ERN COUNTIES...MANY AREAS ALREADY SEEING THE -FZDZ TURN TO -SN. WILL LET FREEZING DRIZZLE ADVISORY FOR ERN CWA EXPIRE. ABR 88D SHOWING ENHANCED AREA OF SNOW FALLING TO WEST OF ABR AND MOVING NORTHEAST. CALLS PLACED UNDER ENHANCEMENT INDICATE HEAVIER SNOWFALL WITH ABOUT 1 INCH ACCUM ALREADY. WILL REDO ZONE ALIGNMENT TO MATCH UP BETTER WITH ENHANCED AREA AND MENTION SLIGHTLY HIGHER ACCUMS. WILL PLAY WITH WINDS AS THEY HAVE ALREADY TURNED TO THE NORTH OUT WEST. WILL ALSO TWEAK TEMPS AS PLACES OUT WEST HAVE REACHED THEIR HIGH...AND TEMPS FOR THE ERN CWA SHOULD BE STEADY. UPDATES OUT SHORTLY. .ABR...NONE. HINTZ sd DEEP SOUTH TEXAS FORECAST DISCUSSION...CORRECTION NATIONAL WEATHER SERVICE BROWNSVILLE TX 930 AM CST MON JAN 3 2000 PER LATEST SURFACE ANALYSIS AND 12Z UPPER AIR CHARTS...PRE-FRONTAL PRESSURE TROF CURRENTLY LIES OVER MID-LOWER VALLEY WITH 850 HPA INVERTED THERMAL TROF ENCOMPASSING DEEP SOUTH TEXAS. THIS HAS SHIFTED WINDS DOWN IN THE RIO GRANDE VALLEY TO A WEST COMPONENT AT THE SURFACE WITH STRONG S-SWLY WINDS STILL AT 40 KNOTS IN THE 2 TO 4 FT LAYER ON BROWNSVILLE RADAR VAD WIND PROFILER. 12Z RUC SHOWS PRE- FRONTAL TROF AND 850 INVERTED THERMAL TROF MOVING OFFSHORE AROUND 18Z AS COLD FRONT MOVES THROUGH THE LOWER VALLEY TURNING WINDS TO NORTHWEST DOWNSLOPE. THIS WILL MOVE LOW LEVEL CLOUDS THAT ARE CURRENTLY OVER THE LOWER VALLEY OFFSHORE AS WELL AS WARM UP TEMPERATURES WITH DOWNSLOPE COMPONENT. SUBSTANTIAL COLD AIR ADVECTION AND STRONGER/DRIER NWLY FLOW REGIME WILL NOT BE REALIZED UNTIL TONIGHT AND TUESDAY. AFTERNOON HIGHS TUESDAY WILL BE ABOUT 15 TO 20 DEGREES COOLER THAN THIS AFTERNOON. NEW 12Z ETA SHOWS 570 DM THICKNESS AND 925 HPA 20 DEGREE ISOTHERM WILL BE OVER THE VALLEY THIS AFTERNOON WITH 555 DM THICKNESS CONTOUR AND 925 HPA 5 DEGREE ISOTHERM OVER THE AREA BY TUESDAY AFTERNOON. WITH SURFACE HIGH SETTLING IN TUESDAY NIGHT/WEDNESDAY MORNING...MUCH DRIER AIRMASS AND LIGHT WINDS...RADIATIONAL COOLING WILL BE OPTIMIZED. CURRENT FORECAST HAS THESE TRENDS WELL IN HAND AT THIS TIME. NO CHANGES. MARINE...SCA WILL BE CONTINUED UNTIL THE EARLY AFTERNOON. BUOY 35 MILES NORTHEAST OF PORT MANFIELD STILL SHOWS SEAS AROUND 9 FEET...BUT SURFACE WINDS HAVE SLACKENED WITH A SW COMPONENT AT 14 KNOTS. LAGGING CORRESPONDING SEAS WILL SLACKEN LATER THIS AFTERNOON. MAY NEED TO PUT UP SCA AGAIN TONIGHT AS NWLY WIND INCREASES. SYNOPTIC/MESO...CORDERO/HMT...ABBOTT .BRO...SCA GMZ150-155-170-175 THROUGH EARLY AFTERNOON. tx UTAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SALT LAKE CITY UTAH 300 AM MST MON JAN 3 2000 SYNOPSIS...A WEAK COLD FRONT WILL PASS THROUGH TODAY...TO BE FOLLOWED BY A WARM FRONT INTO NORTHERN UTAH TONIGHT AND EARLY TUESDAY. THE NEXT COLD FRONT IS EXPECTED TO MOVE ACROSS THE STATE LATE TUESDAY INTO WEDNESDAY. DISCUSSION...SHOWERS NOT TOO WELL ORGANIZED OVERNIGHT. STILL TIME LEFT FOR LAKE ENHANCEMENT AND RUC TURNS STEERING WINDS MORE NORTHERLY BY MORNING THUS ZONES 3 AND 4 STILL COULD GET ADVISORY AMOUNTS. JET AXIS SLIDES INTO EASTERN CWFA EAST BY AFTERNOON AND WESTERN PORTION STABILIZE. NO NEED TO DROP ADVISORY TIL JET AXIS PASSES. 03Z ETA RUN PROGS PRECIP OVER MTNS DOWN INTO MID ZONE 17 BY THROUGH 18Z THUS WILL RAISE POPS. OVERRUNNING CLOUDS UPSTREAM MAY BE A SIGN THAT PROGGED WAA MAY PRODUCE MORE WEATHER FOR TUESDAY AT LEAST IN NORTHERN MOUNTAINS AND THIS IDEA SUPPORTED BY 03Z ETA RUN THUS WILL RAISE POPS. FRONT STILL PROGGED INTO NORTHWEST CWFA LATE TUESDAY BUT TROUGH AND COLD AIR MOVE EAST ON WED THUS WED MAY BE SHOWERY AND MAY NEED TO TONE DOWN FORECAST. TUESDAY NIGHT LOOKS LIKE BETTER PERIOD AND MAY ADD GHOST PERIOD TO SOME NORTHERN ZONES. MEDIUM RANGE MODELS CONTINUE LOWER AMPLITUDE PATTERN WITH SERIES OF SMALL PROGRESSIVE WAVES WHICH GET OUT OF PHASE BY END OF WEEK MAKING IT DIFFICULT TO GET FANCY WITH FORECAST. WILL GO WITH A BLEND AND HAVE A CHANCE-OF BY DAY 5. SLC 913 CDC 4-- BURCH .SLC...SNOW ADVISORY INTO AM...ZONES UT1>4,6>8,ID24-25. ut WESTERN COLORADO & EASTERN UTAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 300 AM MST MON JAN 3 2000 00Z MODEL RUNS ALL IN FAIRLY CLOSE AGREEMENT IN HANDLING OF MAJOR FEATURES. AS MIGHT BE EXPECTED RUC IS PICKING UP SOME FINER DETAILS COMPLETELY OVERLOOKED BY ETA...NGM AND AVN. GENERALLY...YESTERDAY/S SYSTEM EXITING INTO OK...AND LAST IN SERIES OF SYSTEMS EMBEDDED IN WESTERN U.S. LOW PRESSURE TROUGH TO AFFECT CWA TODAY. OVERALL PATTERN NOT PROGRESSING EASTWARD QUITE AS QUICKLY AS PREVIOUSLY EXPECTED... PREVIOUS FORECAST PUT FRONT EDGE OF JET MAX INTO NORTHERN PORTION OF CWA SUNDAY NIGHT...NOW APPEARS THIS TO OCCUR TODAY INSTEAD AND NUDGING SLIGHTLY FURTHER SOUTH. TODAY/S SYSTEM APPEARS WEAKER THAN THOSE OF THE LAST COUPLE OF DAYS AND AM NOT EXPECTING DYNAMICS TO CAUSE ADVISORY CRITERIA SNOW. THUS...WILL LET CURRENT ADVISORY EXPIRE WITH MORNING PACKAGE. HOWEVER...WITH MOIST AIR MASS IN PLACE AND EVEN WEAK DYNAMICS...THERE WILL BE SOME AREAS OF SNOW...ESPECIALLY OVER THE MOUNTAINS. THE HIGH PRESSURE RIDGE CURRENTLY OVER THE EASTERN PACIFIC TO PUSH IN OVER CWA TONIGHT AND TUESDAY FOR A BRIEF REPRIEVE FROM THE RECENT FLURRY OF ACTIVITY. GUIDANCE TEMPS HAVE BEEN ALL BUT USELESS LAST COUPLE OF DAYS AND AM GOING TO LET RECENT EVENTS GUIDE THE SHORT TERM. WITH CURRENT BREAKS IN CLOUDS WILL START OFF CONSIDERABLY COLDER THIS MORNING BUT AM EXPECTING SOME SUNSHINE LATE IN DAY. FOR EXTENDED... NEXT SYSTEM TO APPROACH CWA WEDNESDAY AS RIDGE CONTINUES CONTINUES EAST AND ANOTHER LOW PRESSURE TROUGH CUTS IN OVER THE WEST. AVN AND MRF AGAIN WANT TO TRACK THE FIRST EMBEDDED SYSTEM ACROSS THE NORTHERN PORTION OF THE CWA INSTEAD OF DIGGING IT SOUTH WITH THE TROUGH. HOWEVER IF MEMORY SERVES THIS IS SIMILAR TO THE INITIAL TRACK OF YESTERDAY/S SYSTEM WHICH ENDED UP GOING WELL INTO AZ AND NM. SO WON/T START COUNTING ANY CHICKENS YET AND WILL KEEP THE MENTION OF CHANCE OF SNOW ACROSS CWA. THE NEXT SYSTEM DIVES IN THURSDAY AS BACK EDGE OF TROUGH BECOMES POSITIONED OVER CWA FOLLOWED BY ANOTHER BRIEF RIDGE FOR FRIDAY. AM SPLITTING ALL EXTENDEDS INTO SEPARATE DAYS PRIMARILY TO ALLOW FOR TEMPERATURE VARIATIONS ADVERTISED IN MRF GUIDANCE. WESTERN COLORADO AND EASTERN UTAH EMERGENCY MANAGERS SHOULD MAINTAIN A HEIGHTENED LEVEL OF WEATHER AWARENESS TODAY DUE TO CONTINUED LIGHT SNOW SHOWERS ON TOP OF ICY CONDITIONS CURRENTLY IN PLACE. .GJT...NONE. GL co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE QUAD CITIES IA IL 300 PM CST MON JAN 3 2000 18Z SFC ANALYSIS DEPICTS 1004 LOW DEVELOPING ACRS SOUTHWEST MO... CLOSE TO 12Z ETA AND LATEST RUC. BEST PRESSURE FALLS OCCURRING TO THE NORTHEAST OF IT ACRS EAST CENTRAL MO AND ACRS CENTRAL IL. SFC-H85 BAROCLINICITY/THERMAL THONG/ ALSO STRETCHED ALONG SAME ROUTE... SHOWING THE WAY OF SFC WAVE PROPAGATION. AGAIN LATEST RUC AND ETA SEEM TO HAVE BETTER HANDLE OF PROJECTED PATHWAY AND WILL FOLLOW. NORTHEAST SFC WINDS BACKING TO NORTH ACRS NORTHERN HALF OF CWA IN RESPONSE TO DEEPENING SYSTEM. BLUE RIVER PROFILER SHOWING DEEPENING NORTHEAST FLOW APPROACHING THE H85 LEVEL...WHICH SHOULD ADVECT COOLER H85 TEMPS ACRS WI OVER DVN CWA SUPPORTING ALL SNOW. SFC OBS AND PHONE CALLS ALREADY REPORTING LIGHT TO MODERATE SNOW BREAKING OUT ACRS WEST CWA....TO GO ALONG WITH BLOSSOMING 88D IMAGERY. THIS INDICATES ISENTROPIC/INCREASING VERTICAL LIFT TAKING OFF ACRS PARTS OF CWA. ETA ALSO BETTER AT HANDLING DEFORMATION ZONE DEVELOPMENT ACRS EAST KS INTO NORTHWEST MO...AND BRINGS IT NORTHEAST ACRS MUCH OF CWA OVERNIGHT. SFC LOW SHOULD TRACK TO STL VCNTY BY 00Z...AND THEN PIVOT NORTHEAST TO A NORTH CENTRAL IN/SOUTHWEST LOWER MI POSITION AROUND 06Z TUE. THIS WOULD SUPPORT 130-150 NMI HEAVIER SNOW BAND PLACEMENT RULE ACRS CENTRAL POSITIONS OF DVN CWA... GENERALLY 50 MI OR SO EITHER SIDE OF THE MS RVR. REGIONAL/MOSAIC 88D LOOP DEFORMATION ZONE TRENDS CURRENTLY ACRS NORTHWEST HALF OF MO AND TAKING SFC LOW TRACK INTO ACCOUNT...SUPPORT THIS SCENARIO. H7 LOW ALSO PROGGED TO TRACK JUST WEST OF MS RIVER SUPPORTING HEAVIER SNOW BAND. THIS COMBINED WITH THE ALREADY OCCURRING ISENTROPIC SNOW ACRS AREA SUPPORT ONGOING WSW'S...AND WILL LIKELY ADD TO. MOST OR ALL OF CWA PROBABLY WILL BE UNDER WINTER STORM WARNING OR WINTER WX ADV FOR TONIGHT. ALSO...UPPER VORT MAX HANGING BACK ACRS OK WITH HEAVY SNOW EXTENDING ACRS KS...MAKES ME NERVOUS ABOUT EXTENDED SNOW EVENT OVERNIGHT. AS STATED BEFORE...CRITICAL/PARTIAL THICKNESSES AND ONGOING OBS SUPPORT ALL SNOW...EXCEPT ACRS EXTREME SOUTHEAST IA AND WEST CENTRAL IL. MODELS QUICKLY COOL THESE PARAMETERS ACRS THESE AREAS TO ALL SNOW CRITERIA JUST AFTER 00Z...BUT FEEL IT WILL GO QUICKER THAN THAT. AGREE WITH ILX THAT INITIAL WARM GROUND AND MARGINAL AMBIENT TEMPS WILL CUT BACK ON INITIAL ACCUMULATIONS...BUT CONTINUING SNOW FROM BAND EXTENDED WAY OUT SOUTHWEST COULD ACCUMULATE LATER TONIGHT TO ADVISORY CRITERIA. STRONG NORTH WINDS BLOWING IT AROUND...EVEN THOUGH IT MAY BE OF WET VARIETY...SUPPORT ADVISORY FOR TREACHEROUS CONDITIONS AS WELL. THIS SYSTEM WILL QUICKLY INGEST COLD AIR FROM THE NORTH AS BOUNDARY LAYER TO H85 TEMPS CRASH TONIGHT. AS FOR AMOUNTS AND AREA EXTENT... FEEL EARLIER WINTER STORM WARNING UPGRADE HAS GOOD HANDLE...BUT MAY EVEN ADD A TIER OF COUNTIES TO WEST. 290 TO 295 K GARCIA ANALYSIS AND AVERAGE-ADVECTED IN SPECIFIC HUMIDITIES SUPPORT 6 TO 8 INCHES ACRS CENTRAL CWA IF LIFT WAS TO LAST 12 HRS. BUT BEST LIFT PROGGED TO SHIFT NORTHEAST WITH SFC WAVE AFTER 02Z. MAIN DYNAMICS/POS OMEGAS THEN TAKE OVER AS DEFORMATION ZONE SWEEPS ACRS MUCH OF CWA. HEAVIEST SNOW LOOKS TO OCCUR WITH POS OMEGA BULLSEYE AND 90+ RH/S EXTENDED UP TO H5 MB FROM 00Z TO 06Z TUE. PARAMETERS IN THIS TIME ZONE FROM 00Z-04Z ACRS CENTRAL CWA ALSO SUPPORT DENDRITIC FLAKE SCENARIO WHICH COULD SUPPORT AT LEAST INCH/HOUR RATES. LOOKING AT H5-H3 POTENTIAL VORT AND H2 TEMP PROFILES...TROP FOLD AND THUS WARM POCKET EXTENDING TO AT LEAST 450 MB MAY ADD CYCLOGENESIS PUNCH...STRENGTHENING SFC LOW BEYOND PROGGED LEVELS. COOK METHOD/FOR WHAT ITS WORTH/ SUPPORTS UP TO 8 INCH AMOUNTS ACRS CWA. ALL IN ALL...WILL CONTINUE WINTER STORM WARNING FOR 4-8 INCH AMOUNTS ACRS ONGOING AREA TONIGHT...AND ADD A FEW COUNTIES EITHER SIDE. REST OF CWA TO BE UNDER WINTER WX ADVISORY FOR LESSER AMOUNTS. ...EXTENDED...THU-FRI-SAT... QUICK LOOK AT EXTENDED...MRF AND EUROPEAN BRING NORTHERN STREAM UPPER LEVEL WAVE ACRS THE NORTH CENTRAL CONUS THROUGH THU MORNING... WITH EURO FURTHER NORTH WITH SFC SYSTEM WELL INTO CANADA...AND THUS LESS CHANCE OF PRECIP. MRF FURTHER SOUTH WITH SFC SYSTEM INTO WESTERN GRT LKS BY 12Z THU...AND THUS BETTER CHANCE OF LIGHT SNOW ACRS NORTHERN HALF OF CWA ON THU. WILL LEAVE ONGOING CHANCE... ALTHOUGH MOISTURE AVAILABILITY AT QUESTION. TROUGH TO INDUCE SFC- H85 WARMING OUT AHEAD OF IT...BUT STILL FEEL FMR NUMBERS BIT WARM AND WILL TONE DONE...ESPECIALLY WITH PROJECTED SNOW COVER. BOTH MODELS COME UP WITH SPLIT FLOW REGIME AT END OF WEEK INTO THE WEEKEND...WITH NORTHERN STREAM ZONAL FLOW OFF OF THE PACIFIC NORTHWEST DEVELOPING ACRS UPPER MIDWEST. AFTER BRIEF COOL SHOT BEHIND DEPARTING TROUGH ON FRI...SOME MODERATION IN SFC-H85 TEMPS OCCURS OUT AHEAD OF NEXT VIGOROUS NORTH STREAM SYSTEM SKIRTING ACRS U.S./CANADIAN BORDER ON SAT. AGAIN EURO FURTHER NORTH IN IT/S SOLUTION HANDLING WAVE THAN THE MRF...BUT BOTH LOOK DRY FRI AND SAT AND WILL GO THAT WAY...ALTHOUGH MRF ADVERTISING LINGERING LIGHT SNOW AND FLURRIES FRI MORNING. COORDINATED WITH MKX...ARX...ILX...LSX...THANX. .DVN... IA...WINTER STORM WARNING FOR TONIGHT EAST OF A DBQ...TO IOWA CITY... TO WASHINGTON LINE. WINTER WX ADVISORY TO THE WEST. IL...WINTER STORM WARNING NORTHWEST IL FOR TONIGHT...WINTER WX ADVISORY FOR BUREAU...PUTNAM...AND WEST CENTRAL IL TONIGHT. MO...WINTER STORM WARNING TONIGHT FOR FAR NORTHEAST MISSOURI. JDH il SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE HASTINGS NE 1111 AM CST MON JAN 3 2000 PROFILERS AND SATELLITE LOOPS SHOWING THE UPPER LOW ROTATING NEAR THE OKLAHOMA PANHANDLE...ALTHOUGH THE CIRCULATION ON THE SATELLITE IMAGERY DOES NOT APPEAR TO BE WELL DEFINED. DEFORMATION ZONE IS STILL TRYING TO BECOME ESTABLISHED...AND IS MOST LIKELY SETTING UP JUST TO THE SOUTH OF OUR CWA OVER KS. 17Z SURFACE ANALYSIS SHOWED TWO SURFACE LOW CIRCULATIONS...ONE OVER CENTRAL OK WITH THE OTHER OVER SW MO. THE 12Z ETA AND RUC PHASE THESE TWO LOWS TOGETHER OVER SRN MO AND THEN RAPIDLY MOVE THEM INTO IL BY 00Z THIS EVENING. OF ADDITIONAL CONCERN IS THE LACK OF ISENTROPIC LIFT/THERMAL ADVECTION BELOW H6 OVER THE CWFA. THIS IS CONCENTRATED TO THE SOUTH OF THE AREA...NOT SURPRISING GIVEN THE SURFACE LOW POSITION. THUS ANY LIFT WILL BE FROM BROAD UPPER DIVERGENCE AND WEAK DPVA. STILL SNOWING OUT THE WINDOW AND THERE ARE A FEW POCKETS OF SNOW ON THE 88D WHICH ARE EXPANDING IN SIZE. RECENT CALLS TO COUNTIES CONFIRMS AREAS OF LIGHT TO MODERATE SNOW FALLING ON TOP OF VERY SLICK ROADS AND STILL MANY ACCIDENTS. WITH THE FREEZING DRIZZLE ALREADY ON THE ROADS FROM THIS MORNING...ANY NEW SNOW WILL CONTINUE TO CREATE TRAVEL PROBLEMS THUS HAVE OPTED TO CONTINUE EXISTING WINTER WEATHER ADVISORY INTO THE AFTERNOON. WINDS ALSO PICKING UP AS PLANNED...WITH MODELS SHOWING 850 WINDS UP TO 45 KNOTS BY 00Z. .GID...WINTER WEATHER ADVISORY IN EFFECT THIS AFTERNOON FOR SOUTHERN 2/3 OF CWA. DDN ne FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS 245 PM CST MON JAN 3 2000 FCST CONCERNS...TEMPS/CLOUD TREND TONIGHT...THEN SNOW POTENTIAL TUES NIGHT AND WED. .CURRENT... KMVX 88D SHOWING AREA OF -SN DIMINISHING WITH FLURRIES REMAINING OVER ERN ND AND PARTS OF NW MN. ARCTIC FRONT CONTINUES TO ONLY OOZE EAST WITH SOME TEMP FALL IN ROX-DTL-FFM NOTED IN THE PAST FEW HOURS. STIL IN THE LOWER 20S EAST OF THERE AT PKD. MEANWHILE THE VALLEY AND ERN ND STUCK IN THE SINGLE DIGITS. 50H VORT MAX REMAINS OUT WEST OF BISMARCK AS SHOWN BY NICE SPIN ON SATELLITE IMAGERY...AND WILL HAVE TO WAIT TIL THIS AND ENTIRE 50H TROF MOVES EAST BEFORE ANY SIGNIFICANT CLEARING BEGINS. .SHORT TERM... WILL CONTINUE WITH MENTION OF CLOUDS AND SOME FLURRIES THIS EVENING IN MOST ZONES...FOLLOWED BY GRADUAL CLEARING FROM WEST TO EAST OVERNIGHT. USING 18Z RUC AND AXIS OF 50H TROF...WILL PROG MAIN CLEARING INTO THE DVL ZONE 03-06Z...GFK-FAR ZONES 07-10Z AND BJI-FFM AREA AROUND 12Z. TEMP BUST POTENTIAL BIG TONIGHT AS EXPECT TEMPS TO TUMBLE (PROVIDED IT CLEARS)...SPCLY IN DVL/GFK ZONES DUE TO FRESH SNOW COVER AND ENTRENCHED ARCTIC AIRMASS. -22 AT 85H AT KGGW AT 12Z...AND LOOK FOR THIS AIR TO BE OVER CWFA BY 12Z TUES. BUT WILL NOT GO OVERBOARD AS SFC WINDS WILL REMAIN UP MOST OF THE NIGHT AS SFC RIDGE AT 12Z REMAINS OVR CNTRL ND. WILL GO BLO FWC MOS IN DVL/GFK ZONE AND AOA FWC MOS IN MUCH OF MN DUE TO CLOUDS. .LONGER TERM... BRIEF PD OF SUN EARLY TUESDAY...BEFORE WARM ADVECTION CLOUDS INCREASE FROM WEST TO EAST. TEMPS ONCE AGAIN A BIG HEADACHE...BUT EXPECT ARCTIC AIRMASS TO REMAIN IN PLACE IN MOST ZONES KEEPING HIGHS MOSTLY IN THE SINGLE DIGITS...WITH SOME TEENS WCNTRL MN ZONES. ATTENTION FOCUSES ON NEXT SYSTEM NOW ENTERING THE BC/WASHINGTON COAST. SYSTEM LOOKS IMPRESSIVE AND THINK IT COULD DUMP A FAIR AMOUNT OF SNOW TO PARTS OF THE NRN CWFA. LIKE ETA/AVN AND ITS TRACK WITH THIS SYSTEM...HAVING SFC LOW NR MOT 12Z WED AND THEN TO JUST EAST OF GFK BY 00Z THU. TRACK OF 85H LOW RIGHT ALONG US/CANADA BORDER AND EXPECT BEST SNOWS ALONG THIS BAND. STRONG 85H WARM ADVECTION 06-12Z WED...AND 285K ISENTROPIC SFC SHOWS GOOD LIFT WITH SPEC HUMIDITY INCREASING TO 2.5-3 G/KG IN ERN ND. 85H TEMPS INCREASE TO 0C SRN ZONES BY 12Z WED ON ETA WITH AVN BLO OC. LOW MOVES TO NR DLH BY 00Z THU BUT WRAPAROUND SNOWS SHOULD CONTINUE WEST INTO CWFA ALONG INVERTED TROF. WILL HAVE SNOW DEVELOP IN WAA PATTERN TUES NIGHT AND THEN CONTINUE WED...WITH HIGHEST POPS NRN ZONES. TRACK OF SFC/85H LOW INDICATING BEST SNOWS ALONG AND NORTH OF A DVL-GFK-BJI LINE. CONDESATION PRESSURE DEFICITS AND RH ALSO PINPOINT NRN ZONES FOR BEST CHC OF SNOW. NO HEADLINES OR AMOUNTS NEEDED ATTM SINCE IT IS IN THE 3RD AND 4TH PD. POTENTIAL FOR FZRA WAS BROUGHT UP BY WFO ABR IN COORD CALL...BUT ATTM WILL NOT MENTION IN FAR SRN ZONES AS FCST SOUNDINGS FOR SE ND CORNER AT 12Z WED INDICATE COLUMN AOB 0C. EXTENDED...LONG RANGE MODELS SIMILAR IN KEEP CWFA UNDER ACTIVE PATTERN THROUGH THE EXTENDED FORECAST PERIOD. INITIALLY...MRF AND UKMET ARE PRETTY SIMILAR WITH ECMWF SLOWEST OF THE THREE. MRF AND UKMET MOVE SFC LOW INTO LK SUPERIOR WITH INVERTED TROF BACK INTO N PART OF CWFA BY 12Z THU...SO WILL KEEP IN CHC OF SNW AS ALREADY ADVERTISED FOR THU. THEN...BY 12Z FRI...MODELS COME INTO BETTER AGREEMENT WITH SFC RIDGE BUILDING IN OVER CWFA AS NEXT SYSTEM ORGANIZES IN CANADIAN ROCKIES. UKMET AND ECMWF THEN BECOME MORE CONSISTENT THROUGH THE LATTER PARTS OF THE EXTENDED...WITH MRF DEVELOPING A SFC LOW FASTER AND LOCATING IT FARTHER S...WHILE UKMET AND ECMWF KEEP SFC LOW IN N SK. WITH MRF DEVELOPING SFC LOW MUCH FARTHER S THAN OTHER TWO MODELS...WILL DISREGARD PLACEMENT AT THIS TIME...AND KEEP CONTINUITY WITH PRIOR FORECAST OF NO PCPN FOR FRI TO SUN TIME PERIODS. HOWEVER...LOW DOES APPROACH FOR MON...SO WILL PUT CHC OF SNW IN MON FORECAST. AS FAR AS TEMPS...WITH NEW SNOWCOVER AND ADDITIONAL ACCUMS POSSIBLE BEFORE EXTENDED PERIOD...WILL KEEP CONTINUITY WITH PRIOR FORECAST AND CUT BACK SIGNIFICANTLY ON MRF GUIDANCE NUMBERS. HOWEVER...STILL EXPECT TEMPS TO BE IN NORMAL TO SLIGHTLY ABOVE NORMAL RANGE. .FGF...NONE. RIDDLE/NG nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON WV 7 AM EST MON JAN 3 2000 UPDATE TO EXTEND HIER POPS EWD FM SWRN THRU NERN WV...WAVE RIPPLING ALONG 850 THETA E RIDGE STRONG ENUF TO PUSH SHWRS A LITTLE FARTHER EWD THAN FCST. SHWRS SHOULD STILL LIFT NWD OUT OF AREA THIS AFTN PER NEW 06Z MESOETA AND RUC. .RLX... WV...NONE. VA...NONE. KY...NONE. OH...NONE. .END/JMV wv AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 258 PM CST MON JAN 3 2000 FCST FOCUS ON SYSTEM MOVG UP FM SRN MO FOR TONIGHT AND EARLY TUESDAY. SEEDER-FEEDER MECHANISM SHOWING UP WELL ON KMKX 88-D. -DZ FALLING AT OFFICE ATTM..WITH HIGHER LVL RETURNS MOVG IN FM SW. MSN REPORTED -DZ WITH 30F...THEN WENT TO -SN AS HIER SEEDER CLDS MOVED OVR SITE. DBQ REPORTED FZRA FM 1717Z TO 1929Z THEN WENT TO SNOW. VAD WIND PROFILE SHOWS RETURNS LOWERING FM 10K FT AS ICE CRYSTALS FALL FROM BASE OF MID DECK. THIS WL MOISTEN DRY LAYER BETWEEN 7 AND 10K FT THAT RUC BUFKIT SNDGS WERE DEPICTING ...AND ALLOW CRYSTALS TO GROW WITH MOISTURE IN THE LOWER LVLS. TEMPS UNDER 32F IN WRN CWA MEANS POSSIBLE FZDZ BEFORE GOING OVR TO ALL SNOW...BUT WILL NOT LAST LONG AS MID DECK SHUD COVER ALL OF CWA BY 5 PM. 18Z RUC VERIFYING 12Z MDL RUNS...TAKING SFC LO IN SRN MO OVR NRN IN. INTO SRN LWR MI BY 12Z. BANDS OF PCPN FILLING IN FM SW WI TO ERN KS BEGINNING TO DEFINE SNOW AREA THAT WILL CROSS SRN WI OVRNGT. 18Z RUC H7 UVV FIELDS SIMILAR TO 12Z ETA. WETZEL FCST INGREDIENTS MACROS ON AWIPS SHOW Q VECTOR CONVERGENCE SUSTAINED OVER ERN 2/3 OF CWA THRU 06Z AND LINGERING IN THE EAST TIL 12Z. SPEC HUMIDITIES ARE IN THE 3- 4G/KG RANGE. H8 TEMPS HANG IN THE 0C RANGE OVER RACINE AND KENOSHA CNTYS...SO SNOW AMOUNTS MAY BE LIMITED BY MIX WITH RAIN. WL UP SNOW ACCUMULATIONS SLGTLY FOR IOWA...SAUK AND MQT CNTYS. CURRENT BAND COULD LAY DOWN A FAST 1 TO 2 INCHES BEFORE 00Z...SO WL EXPAND THE RANGE SLGTLY. OTHERWISE...CURRENT WARNING AND ADVISORIES AND EXPECTED SNOW AMOUNTS WL REMAIN IN PLACE. LONGER TERM...RDG BUILDS IN QUICKLY WITH COOLER TEMPS TUE NGT...BUT NEXT SYSTEM RACES SEWD INTO NRN PLAINS BY WED MORN. WAA AHD OF SYSTEM WL BRING CLDS BACK IN AND NUDGE TEMPS UP FOR WED BEFORE PCPN BEGINS WED NGT INTO THU. GUIDNC TEMPS REASONABLE. THANKS TO DVN...LOT...ARX AND GRB FOR COORDINATION TDY. .UWNMS...NOT AVBL. .MKX...WINTER STORM WARNING TNT...WIZ047-051-052-057>059-060-063>066- WINTER WEATHER ADVISORY TNT...WIZ046-056-062-071-072. /...0.../.../ REM wi