AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 931 PM CST TUE JAN 11 2000 LTL CHGS NEEDED FOR EVENING UPDATE AS PREVIOUS FCST ON TRACK. 00Z UPR AIR ANLYS INDCS IMPRESSIVE ISENT LIFT UNDERWAY BUT WITH LTD MSTR ONLY MID/HIGH CLOUDS DVLPG. 03Z SFC ANLYS PLACES WRMFNT ACRS NRN NE INTO NRN MO...AND ARCTIC BNDRY FM GTLKS INTO SRN MN AND NERN SD. 00Z RUC AND 18Z ETA KEEP BEST FORCING AND SATURATION JUST N OF FA INTO WED MRNG. PCPN WL LIKELY RMN OVR MN BUT WL KEEP LOW POPS GOING OVR NRN ZNS AS CONFIDENCE NOT HIGH ENOUGH TO DROP ALTOGETHER. WITH STG LOW LVL WRM ADVCTN UNDERWAY TNGTS LOWS SEEM GOOD WITH LTL FALL XPCD...SPCLLY WITH CLOUDS PERSISTING. GOOD THING ITS NOT A FEW MORE MONTHS ALG WITH MORE MSTR AS VERTICAL WND SHEAR QUITE IMPRESSIVE ALG WRMFNT. 30-40KT LOW LVL JET DVLPG INTO ERN NE. .DSM...NONE. SMALL ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1010 PM EST TUE JAN 11 2000 LES APRS TO BE GRADUALLY DIMINISHING...W/ PHONE CALLS TO SVRL SNOW SPOTTERS FM THE KEWEENAW PENIN TO ONTONAGON REVEALING MAINLY LIGHT FINE...SNOW AND WNDS ARND 10KT AT THE LWR ELEVS. 18Z/NEW 00Z ETA AND THE LATEST RUN OF THE RUC BOTH SHOW DELTA T VALUES DCRSG BY A CPL OF DEGS OVNT. INL SOUNDING SHOWS INVERSION AT 900MB...OR ABT 2K FEET. 18Z ETA FCST SOUNDING INFORMATION SHOWS INVERSION DROPPING TO ARND 3K FEET OVR THE WRN LAKE. SHIFTING WINDS BCMING MORE ANTICYCLONIC AND THE DCRS IN MIXING WL ALL DCRS TO CONT. WL DROP ADVSRY FOR NW ZONES...THO WL MENTION ISOLATED 2 INCH AMTS AT THE HIGHER ELEVS. FURTHER E...LAKE INDUCED TROF WL KEEP LOW LVL CONVERGENCE THRU THE NGT. INVERSION FCST TO DROP A TO JUST TO ARND 4500 FEET TNT... LAPSE RATES IN THE 1000-850 LYR RMN AOA 8 DEG C/KM THRU THE NGT...BUT AXIS SHIFTS E TWD SSM PER THE 18Z ETA AND NEW 00Z ETA DATA OVNT. IN ADTN...STRONGEST CONVERGENCE AT H95 ALSO SHIFTS EWD. REGIME AND WNDS FM 290-300 FVRBL FOR LES E OF MSN...BUT GIVEN XPCTD SHIFT E OF MOST FVRBL CONDITIONS WL FCST ONLY ANOTHER 1 TO 3 INCHES E OF MUNISING. OTHER QUESTION FOR UPDATE IS OVNT LOWS. WL XPCT CLDS TO DIMINISH ALG THE LAKE SHORE IN THE W...SO WL LUK FOR A SHARP DROP OFF IN TEMPS AT CMX/ONT ETC OVNT...TO CRNTLY FCST LVLS. IN THE INTERIOR AREAS AWAY FM LAKE SUPER...DWPTS DOWN INTO THE SINGLE DIGITS AND BLO ZERO... SKIES ARE CLR AND WNDS HAVE DIMINSHED TO UNDER 10KTS AT MOST LOCNS. WL LOWER TEMPS MOST AREAS...W/ A RANGE FM ALG THE LAKE TO INLAND. .MQT...NONE. DESROSIERS mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 845 PM CST TUE JAN 11 2000 ZONE FORECASTS HAVE BEEN UPDATED TO INCREASE MENTION OF SNOW TONIGHT. LATEST RUC MODEL DEVELOPS ISENTROPIC LIFT TO SATURATION AT 285K AND 290K SURFACES WHICH IS ROUGHLY 700MB IN THE FORECAST AREA. MOST OF THE WIND IS ALONG STREAM...BUT WITH RELATIVELY STRONG FLOW...THERE SHOULD BE ENOUGH CROSS ISOBARIC FLOW TO GENERATE SOME LIGHT SNOW OR FLURRIES OVERNIGHT. IN ADDITION THERE IS A HINT OF UPPER DIVERGENCE WITH STRONG E-W JET AND SUGGESTION OF TRANSIENT LEFT EXIT REGION OF 250-300MB JET. INITIAL 00Z ANALYSIS/SATELLITE IMAGERY CONTINUES TO INDICATE STRONG PACIFIC TROUGH DRIVING INTO PACIFIC NW...90 METER HEIGHT FALL SHOWING UP AT 500 MB IN MEDFORD OR. ALL MODELS HAVE BEEN TRENDING TOWARD DEEPER TROUGH WITH EACH RUN. THERE SHOULD BE A FOCUSED SNOW BAND OF SEVERAL INCHES...WITH SUGGESTED SNOW MAXIMUM IN OR NORTH OF TWIN CITIES. ADVISORY IS ALMOST CERTAIN FOR FOR SOME PORTION OF FORECAST AREA ON WEDNESDAY. UPDATES WILL BE CONSIDERED. .MSP...NONE SCOTT mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 1015 AM CST TUE JAN 11 2000 ...FORECAST FOCUS IS ON TEMPERATURES FOR THIS AFTERNOON AND TONIGHT... A LOOK AT THE MODEL SOUNDINGS...DISPLAYED VIA BUFKIT...ACROSS OUR CWA WAS QUITE REVEALING THIS MORNING. 00Z NGM AND 00Z ETA 18Z SURFACE TEMPERATURE FORECASTS ARE 5 DEGREES C/ 9 DEGREES F/ WARMER THAN THE CORRESPONDING FORECAST FROM THE 12Z RUC2 RUN. A LOOK AT OBSERVED TEMPERATURES CERTAINLY COMPARES FAVORABLY WITH THE RUC2 18Z FORECAST. SO HAVE KNOCKED ABOUT 8 DEGREES F OFF THE PREVIOUS FORECAST MAXIMUMS FOR THIS AFTERNOON. ALTHOUGH CLOUDS WILL BE STREAMING INTO THE CWA FROM THE UPWIND WEATHER DISTURBANCE TONIGHT...HAD TO LOWER TONIGHT'S FORECAST MINIMUMS DUE TO THE EXPECTED 00Z READINGS BEING CONSIDERABLY COLDER THAN PREVIOUS ZONE FORECASTS. TEMPERATURES LIKELY TO REMAIN NEARLY STEADY OR RALLY SOMEWHAT OVERNIGHT AS WARM ADVECTION BEGINS IN EARNEST. LEFT FORECAST FOR WEDNESDAY ALONE. ONE LAST COMMENT ON FORECASTS FOR THIS AFTERNOON...INTERESTING THAT THE LAMP FORECASTS DID NOT PICK UP ON THE UPWIND TEMPERATURES. SPOT LAMP FORECASTS ARE NOT MUCH DIFFERENT THAN THE CORRESPONDING 00Z MOS GUIDANCE. .MSP...NONE RJN mn AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE SPRINGFIELD MO 1056 AM CST TUE JAN 11 2000 UPDATED ZONES TO ADJUST TEMPERATURES AND FOR HIGH CLOUDINESS STREAKING ACROSS THE AREA. THE RUC TAKES MOST OF THE HIGH CLOUDS OUT OF THE AREA THIS AFTERNOON...BUT MENTIONED IT IN THE SOUTH CENTRAL ZONES WHERE CLOUDS WILL BE LAST TO LEAVE. CLOUDS ALSO SUPPRESSING TEMPERATURES A LITTLE THIS MORNING. WITH HIGH PRESSURE MOVING OVERHEAD AND LIMITED MIXING...ADJUSTED TEMPERATURES DOWN JUST A BIT. .SGF...NONE. FOSTER mo MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAS VEGAS NV 905 AM PST TUE JAN 11 2000 SYNOPSIS...A STORM SYSTEM OVER THE PACIFIC NORTHWEST WILL SLOWLY MOVE ACROSS NORTHERN NEVADA TODAY. IN ADVANCE OF THIS SYSTEM...WINDS WILL INCREASE ACROSS THE REGION WITH BREEZY TO WINDY CONDITIONS CONTINUING INTO TONIGHT. THE SYSTEM WILL BRING A CHANCE OF SHOWERS TO THE SIERRA AND SOUTH CENTRAL NEVADA...BEFORE EXITING THE REGION LATE TONIGHT. DRY AND BREEZY CONDITIONS WILL PERSIST OVER THE REGION ON WEDNESDAY. DISCUSSION...140-150KT JET AND BAROCLINIC ZONE ALONG THE NORTHERN CALIFORNIA AND NORTHERN NEVADA BORDERS THIS MORNING. AS THE JET SAGS SOUTH TODAY...GRADIENTS TIGHTEN WITH RUC/NGM BOTH FORECASTING 45-55 KTS AT 700 MB OVER ESMERALDA AND NORTHERN NYE COUNTIES THIS AFTERNOON. SURFACE GRADIENTS STILL BORDERLINE FOR WIND ADVISORY BUT FEEL STRONGER GRADIENTS/WINDS ALOFT HAVE THE POTENTIAL TO MIX DOWN INTO THE VALLEYS FOR GUSTS OF 40-50 MPH. WILL UPDATE FORECAST TO ISSUE WIND ADVISORY FOR NEVADA ZONES 13 AND 14 WITH STRONGEST WINDS EXPECTED LATE THIS AFTERNOON AND EARLY EVENING. LOW AND MID-LEVEL MOISTURE WITH FRONTAL ZONE TO MOVE SOUTH INTO NORTHERN PARTS OF FORECAST AREA THIS AFTERNOON AND EVENING. ETA/NGM KEEP ANY MEASURABLE PRECIPITATION ACROSS NORTHERN CALIFORNIA AND NEVADA AND CURRENT CHANCE MENTION OF SHOWERS OVER THE SIERRA AND MOUNTAINS OF SOUTH CENTRAL NEVADA ON TRACK. JUST MID AND HIGH CLOUDS EXPECTED ELSEWHERE TODAY WITH AFTERNOON BREEZES IN THE 15-25 MPH RANGE. JET AND FRONTAL BOUNDARY RETREAT BACK TO THE NORTH WEDNESDAY MORNING AS TROUGH DIGS IN EASTERN PACIFIC ALONG 140W. ATMOSPHERE DRIES OUT AT THE LOWER LEVELS AND GRADIENTS WEAKEN. REMAINDER OF FORECAST HAS THESE TRENDS AND APPEARS IN LINE WITH CURRENT THINKING. SATURDAY AND SUNDAY OF EXTENDED PERIOD STILL IN QUESTION WITH 00Z MRF SHOWING AN IMPULSE EJECTING FROM THE EASTERN PACIFIC TROUGH...AND PASSING ACROSS NORTHERN CALIFORNIA AND NEVADA. THIS IS SLOWER AND WEAKER THAN PREVIOUS 00Z MONDAY MODEL RUN. NEMETH .LAS...A WIND ADVISORY HAS BEEN ISSUED. PLEASE SEE THE LATEST WIND ADVISORY STATEMENT (RNONPWLAS) FOR DETAILS. nv AREA FORECAST DISCUSSION...UPDATED CWF PORTION NATIONAL WEATHER SERVICE WILMINGTON NC 1018 PM EST TUE JAN 11 2000 FRONT PUSHING ITS WAY TO THE COAST TONIGHT AND DEWPOINTS FALLING OFF QUICKLY BEHIND IT. FRONT TO MAKE IT OFFSHORE OVERNIGHT AND WINDS AROUND TO WEST AND EVENTUALLY TO A NORTHERLY DIRECTION ALL AREAS. MESO ETA AND RUC SHOWING AN ELONGATED VORT MAX OVER TN AND KY. THIS SEEN IN IR SATELLITE IMAGERY. FEATURE IS PROGGED TO WEAKEN AND CLOUD COVER LOOKS TO BE DIMINISHING ON SATELLITE PICTURES. SHOULD NOT PREVENT US FROM SEEING CLEAR SKIES OVERNIGHT. TEMPS TO DROP QUICKLY IN THE OVERNIGHT HOURS AS COOLER AND DRIER AIR WORKS IN. CURRENT FCST IN GOOD SHAPE. WILL JUST CLEAN THINGS UP AND MAKE FINAL TEMPERATURE DECISIONS AFTER A LOOK AT 10 PM OBS. CWF...WINDS STILL IN SCA CRITERIA RANGE AND WILL KEEP ADVISORY THRU THE NIGHT SURF CITY TO LITTLE RIVER. FURTHER SOUTH WINDS AND SEAS HAVE SUBSIDED AND WILL DROP SCA SOUTH PORTION OF WATERS. .ILM...SCA SURF CITY NC TO LITTLE RIVER INLET SC. PJN/PFAFF nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC 940 AM EST TUE JAN 11 2000 CURRENT FCST PACKAGE LOOKS GOOD. ZONAL FLOW WILL CONTINUE THE NEXT COUPLE OF DAYS WITH WARM TEMPERATURES. MHX SOUNDING VERY DRY AND WARM JUST OFF THE SFC. UNDER FULL SUN TODAY TEMPS SHOULD REACH AROUND 70. WINDS WILL INCREASE THIS AFTERNOON WITH A STRONG LOW LEVEL JET MIXING DOWN...AND THE GRADIENT TIGHTENING WITH THE APPROACH OF A DRY FRONT. CWF...WINDS AT THE OFFSHORE BUOYS HAVE PICKED UP TO A SOLID 20 KT...AND ALL THE THE MODELS INCLUDING THE LATEST MESO AND RUC SHOW CONTINUED STRENGTHENING OF THE WINDS THIS AFTERNOON. WILL KEEP SCA IN EFFECT. WINDS WILL SHIFT TO SW AHEAD OF AN APPROACHING FRONT. .MHX...SCA CSTL WTRS AND SOUNDS. RSB nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 832 PM EST TUE JAN 11 2000 WINDS DIMINISHING AS FORECAST SO WE WILL ALLOW WIND ADVISORIES FOR MOUNTAIN AREAS TO EXPIRE. BECAUSE OF THIS...I WILL DO THE EVENING UPDATE A LITTLE AFTER 9 PM...SO I CAN REMOVE HEADLINES. SATELLITE LOOPS AND LATEST RUC SHOWING SOME MID AND UPPER LEVEL MOISTURE MOVING TOWARD NC MTNS THIS EVENING. THIS IS A BIT SOUTH OF WHERE THE 18Z ETA SHOWED THE MOISTURE GOING...SO I WILL ADD A FEW CLOUDS TO NORTHERN PORTIONS OF CWA. DO NOT PLAN MANY CHANGES TO TEMPS. .GSP...NONE RBN sc AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA NATIONAL WEATHER SERVICE ABERDEEN SD 910 PM CST TUE JAN 11 2000 KABR 88D SHOWING MORE RETURNS MOVING INTO THE WESTERN CWA. KPIR POLICE REPORT LIGHT SNOW FALLING SOUTH OF FT. PIERRE AREA...AND THIS LINES UP WELL WITH ENHANCED AREA SEEN ON 88D. WITH ENHANCED AREA ENLARGING SLIGHTLY...WILL TWEAK KPIR ZONE TO SCT LIGHT SNOW. WILL ALSO NEATEN UP WINDS SINCE BREEZY CONDS ALREADY EXIST. FOR THE KMBG AND KABR AREAS...LOOK AT NEW RUC SHOWS THAT LGT SNOW MAY HOLD OFF A BIT LONGER THAN PREVIOUSLY THOUGHT...BUT SHOULD STILL DEVELOP BY 12Z. WILL REMOVE MENTION OF TIMING OF PCPN FOR KMBG...AND JUST SAY "LATE" FOR KABR AREA. WINDS SLOWLY INCREASING IN KMBG...SO WILL REMOVE BREEZY FROM FCST. OTW NO OTHER CHANGES MADE TO FCST AS TEMPS AND WINDS LOOK OK. UPDATES OUT SHORTLY. .ABR...NONE. HINTZ sd AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 849 PM CST TUE JAN 11 2000 GENERAL IDEAS OF PRVS FCST REMAIN INTACT. 02Z SFC ANLYS SHOWING SEMI-STATIONARY FRONT ALONG THE SD/NE AND IA/MN BORDER. QUITE A BIT OF A TEMP GRADIENT SETTING UP WITH CAA FM THE N BEGINNING TO BRING THE POSSIBILITY OF OVERNIGHT LOWS IN THE SINGLE DIGITS. 00Z RUC RUN PROGGING SFC TEMPS AROUND 5 DEG F FOR NRN CWA. RUC/18Z MESOETA NOT TOO STRONG ON BRINGING MUCH PCPN TO THE CWA. HOWEVER...WITH SOME OVERRUNNING AT THE LOWER TO MID LVLS ALONG WITH A 500 MB SHRTWAVE APPROACHING STILL SEE A SLOW BUT EVENTUAL CHC OF PCPN LATER TNGT INTO TMW. WHERE APPROPRIATE...WL ADD A LITTLE BETTER TIMING IN THE FCST FOR DEVELOPMENT OF LIGHT SNOW. ZONE AMD EXPECTED BY 910 PM CST. .FSD...NONE BR sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FORT WORTH TX 930 PM CST TUE JAN 11 2000 WILL UPDATE PACKAGE TO REMOVE REFERENCES TO THIS EVENING. WINDS HAVE BECOME SOUTHERLY OVER MOST LOCATIONS OR SHOULD DO SO SHORTLY...SO WILL JUST GO WITH SOUTH WINDS TONIGHT IN ALL ZONES. I WILL ALSO ADD FOG TO SOUTHERN AND SOUTHEASTERN ZONES LATE TONIGHT WITH SOUTHERLY WINDS AND TEMPERATURES ONLY DROPPING TO NEAR THE DEWPOINT (AND REMAINING QUITE HIGH FOR THIS TIME OF YEAR). ALREADY HAVE MENTION OF LOW CLOUDS IN THESE AREAS. ONE CAVEAT IS HOW FAR NORTH THE FOG WILL MAKE IT. BASED ON RUC GUIDANCE AND TIME HEIGHT CROSS SECTIONS HAVE OPTED TO LEAVE OUT FROM METROPLE NORTH AND WEST...BUT WILL HAVE TO MONITOR. .FTW...NONE. 81 tx DEEP SOUTH TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE BROWNSVILLE TX 855 PM CST TUE JAN 11 2000 A FEW LOW CLOUDS ARE FORMING ALONG THE COAST AND PUSHING INLAND. WE HAVE TEMPORARILY CLEARED HERE AT BRO BUT WILL LIKELY SEE MORE LOW CLOUDS OVERNIGHT. THE EVENING SOUNDING IS SHOWING MORE WIND IN THE LOWEST LEVELS AS COMPARED TO LAST NIGHT. THIS IS LIKELY WHY WE HAVE THE LOW CLOUDS INSTEAD OF THE FOG. CURRENT SURFACE OBS FROM AROUND SOUTH TEXAS SHOW THE SOUTH WINDS STILL IN THE 10 TO 15 KNOT RANGE. LATEST RUC SHOWS OVERNIGHT WINDS TO REMAIN AROUND 10 KNOTS WHILE THE MESOETA AND 00Z ETA SHOW 5 TO 10 KNOTS. BUT OF MORE IMPORTANCE THESE SAME MODELS ARE FORECASTING 30 TO 35 KNOTS AT 925 MB. WILL MAKE A FEW MINOR CHANGES TO THE ONGOING FORECAST TO INPUT SOME LOW CLOUDS OVERNIGHT AND MENTION SOME PATCHY FOG IN CASE THE WINDS DIE DOWN ENOUGH. 69 tx EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN DIEGO CA 940 PM PST TUE JAN 11 2000 STRONG FLOW ALOFT WILL CAUSE WINDY CONDITIONS ACROSS THE HIGHER MOUNTAINS AND DESERTS THROUGH WEDNESDAY AFTERNOON. WIND ADVISORIES AND HIGH WINDS WATCHES ARE IN EFFECT. WEST OF THE MOUNTAINS... ONSHORE FLOW WILL CONTINUE TO DEEPEN THE MARINE LAYER THROUGH WEDNESDAY. NIGHT AND MORNING LOW CLOUDS AND FOG WILL BE WIDESPREAD. OFFSHORE FLOW WILL BRIEFLY RETURN THURSDAY. INCREASING CLOUDS ARE EXPECTED ACROSS SOUTHWEST CALIFORNIA THIS WEEKEND AS A COLD FRONT APPROACHES. ACARS SOUNDINGS ACROSS SW CALIFORNIA THROUGH 0330Z SHOWED WNW WINDS 25 KT AT 4000 FT INCREASING TO 40 KTS AT 10000 FT. THE 11/18Z MESOETA MODEL WAS THE CLOSEST TO THESE OBSERVED WIND SPEEDS WHILE THE SYNOPTIC SCALE MODELS WERE ABOUT 10-20 KTS WEAKER. THE 12/00Z RUC AND ETA MODEL BOTH INCREASE WIND SPEEDS IN THIS LAYER ANOTHER 10-15 KTS BY 12/18Z. ADDING THIS INCREASE TO THE CURRENT OBSERVATIONS WOULD YIELD HIGH WINDS ACROSS HIGHER MOUNTAINS... THROUGH CANYONS...AND ALONG LEE SLOPES AND ADJACENT VALLEY FLOORS WEDNESDAY MORNING. LOCAL WIND SCHEME USING THE NUMBERS FROM THE MODELS HOWEVER ONLY SUPPORTS WIND ADVISORIES FOR THE APPLE/YUCCA VALLEYS. WILL LET HIGH WIND WATCH RIDE FOR NOW BUT ADVISE MIDNIGHT SHIFT MAY WANT TO CHANGE IT TO A WIND ADVISORY VERSUS HIGH WIND WARNING AND MOVE EXPIRATION TIME UP TO THE MID AFTERNOON. THE OTHER SHORT TERM WEATHER PRODUCER IS THE DEEPENED MARINE LAYER. THE 12/00Z KVBG RAOB SHOWS IT DEEPENDED ANOTHER 2000 FEET IN THE PAST 24 HOURS. METARS ACROSS COASTAL SECTIONS AND INLAND VALLEYS SHOW FAIRLY UNIFORM DEWPOINTS...IN THE LOW 50S...SO MODIFICATION OF THE AIR MASS APPEARS COMPLETE. FORECASTS ALREADY HAVE MENTION OF DENSE FOG AND LOW CLOUDS SO NO UPDATE NEEDED. IN THE MEDIUM RANGE ALL THE MODELS CONTINUE TO DIG A TROUGH ALONG 140 WEST LONGITUDE BY WEDNESDAY NIGHT WHICH SHOULD PULL THE BAROCLINIC ZONE NORTHWARD AND DIMINISH THE STRONG WINDS ALOFT. THE TROUGH IS THEN MOVED SLOWLY EASTWARD. THE LATEST MRF IS IN AGREEMENT WITH THE OTHER MODELS IN KEEPING THE TROUGH AXIS WEST OF 130 WEST LONGITUDE THROUGH THE WEEKEND....SO THREAT OF RAIN AT THIS TIME APPEARS MINIMAL FOR EXTREME SOUTHWEST CALIFORNIA. SAN 000 .SAN...WIND ADVISORIES CAZ060 THROUGH 330 AM PST WED HIGH WIND WATCH CAZ055-056-060-061 WEDNESDAY...SEE LAXNPWSAN. BALFOUR ca AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SHREVEPORT LA 135 AM CST WED JAN 12 2000 MODELS ARE IN GOOD AGREEMENT ON THIS RUN. ALL SHOW ZONAL FLOW AT THE BEGINNING OF THE PERIOD BECOMING A BIT MORE AMPLIFIED BY 14/00Z. MOISTURE WILL BE IN VERY SHORT SUPPLY THROUGHOUT THIS FORECAST SO NO RAIN IS EXPECTED. VERY SHALLOW LOW LEVEL MOISTURE IS ADVECTING NORTH THIS MORNING WITH ST AND PATCHY FOG SPREADING ACROSS THE CWFA. LOOKING AT FORECAST SOUNDINGS FROM THE RUC...IT APPEARS THAT THIS LOW CLOUD LAYER SHOULD BE FAIRLY EASY TO BURN THROUGH...EVEN IN JANUARY. A WEAK S/WV MOVING THROUGH THE PLAINS TONIGHT WILL PUSH A SFC BOUNDARY INTO THE AREA TONIGHT. STILL NO SIGNIFICANT MOISTURE TO WORK WITH...BUT IT SHOULD MAKE BOUNDARY LAYER WINDS MORE SWRLY AND STIFLE THE ST/FG DEVELOPMENT. THE FRONT WILL ALSO BRING SLIGHTLY COOLER AIR TO THE AREA...BUT WE WILL REMAIN WELL ABOVE NORMAL GOING INTO THE END OF THE WEEK. GUIDANCE MAXES HAVE BEEN A BIT TOO COOL FOR THE LAST COUPLE OF RUNS. I THINK THEY ARE CLOSER TODAY...BUT PERHAPS STILL A COUPLE DEGS TOO LOW...ESP AT LFK...SO WILL GO 2-3 DEGS ABOVE FWC IN THE 1ST AND 3RD PDS. MINS LOOK OK...SO WILL PROBABLY STAY WITHIN A DEG OR TWO OF FWC ON THE LOWS. 05 PRELIMS... SHV 80/53/72/43 0000 MLU 77/52/68/42 0000 TXK 77/48/70/42 0000 TYR 81/50/72/44 0000 LFK 81/55/74/41 0000 .SHV...NONE. la AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE GOODLAND KS 700 AM MST WED JAN 12 2000 LATEST MSAS SURFACE ANALYSIS HAS SURFACE LOW OVER SOUTHWEST KANSAS WITH A WARM FRONT EXTENDING NORTHEAST TO KHLC AND KIML. THIS WINDSHIFT IS FASTER THAN THE MODELS INDICATED. LATEST RUC/RUCII INDICATES NORTHWEST WINDS THE REMAINDER OF THE DAY. RED WILLOW PROFILER CURRENTLY INDICATING 850 WINDS OF 60 KNOTS. THIS WAS WELL UNDERDONE BY ALL THE MODELS. BOUNDARY LAYER WINDS FORECAST TO INCREASE TO 25-30 KNOTS THIS AFTERNOON OVER THE EASTERN 1/3 OF THE CWA...THEREFORE UPPED WINDS TO BREEZY CATEGORY AND REMOVED MENTION OF SOUTHWEST WINDS BECOMING NORTH FOR TODAY PERIOD. NO OTHER CHANGES MADE. .GLD...NONE. THEDE ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1048 AM EST WED JAN 12 2000 SNOW HAS ALREADY BEGUN ACROSS EAST CENTRAL WISCONSIN...WITH OSH SHOWING VISIBILITIES AROUND A MILE AS OF THE 15Z SURFACE OBSERVATION. THIS SNOW IS DEVELOPING IN A REGIME OF GOOD 850 - 700MB FRONTOGENESIS WITH A WEAK UPPER WAVE MOVING EAST OUT OF SOUTHERN MINNESOTA. GRR 88D INDICATES AN AREA OF HIGH CLEAR-AIR REFLECTIVITIES OVER CENTRAL LAKE MICHIGAN MOVING INTO OCEANA COUNTY. WITH CONSIDERABLE DRY AIR BELOW 750 MB ON ALL 12Z SOUNDINGS NEAR SOUTHEAST MICHIGAN...SNOW WILL AT FIRST LIKELY NOT REACH THE GROUND. HOWEVER...BOTH THE 12Z RUC AND THE 06Z MESOETA DEPICT INCREASING MID-LEVEL UVV DEVELOPING ESPECIALLY OVER THE SAGINAW VALLEY ABOUT 21Z...WITH INCREASING 850 - 700MB FRONTOGENESIS OVER THE SAME AREA BETWEEN 18Z AND 00Z AS THE INITIAL SHORTWAVE SLIDES THROUGH. ALONG WITH THIS...LEFT EXIT REGION OF A 75KT 500MB JET AND THE RIGHT ENTRANCE REGION OF A 140KT 250MB JET ARE OVER EAST CENTRAL MICHIGAN BY NIGHTFALL. THE DRY AIR WILL CERTAINLY TAKE A WHILE TO OVERCOME...BUT INDICATIONS ARE THAT THE AIR MASS BELOW 800 MB WILL MOISTEN ENOUGH IN THE FAR NORTH PART OF THE SAGINAW VALLEY TO MENTION LIGHT SNOW DEVELOPING THERE BY LATE IN THE DAY GIVEN THE MID AND UPPER LEVEL SUPPORT. FEEL THAT ANY SNOW WILL BE PRETTY LIGHT DUE TO THE LOW-LEVEL DRY AIR...WITH BETTER SNOW FOR THE EVENING AND OVERNIGHT HOURS AS THE STRONGER SHORTWAVE OVER SOUTH DAKOTAS MOVES THROUGH...AND WE TAP INTO BETTER MOISTURE FLOWING TOWARD US FROM THE SOUTH. WILL TAPER THE SNOW TO CHANCE FROM SAGINAW TO BAD AXE SOUTH TO I 69...THEN JUST MENTION A FEW FLURRIES POSSIBLE OVER THE M 59 CORRIDOR UP TO PORT HURON. THESE AREAS REMAIN FAIRLY DRY BELOW 750 MB THROUGHOUT THE AFTERNOON AND GETTING MUCH NOTICEABLE SNOW THERE WILL BE DIFFICULT EVEN WITH SOME MID AND UPPER LEVEL SUPPORT. FOR THE FAR SOUTHEAST...THE LATEST VISIBLE SATELLITE IMAGES AND 12Z RUC/06Z MOISTURE PROFILES SUGGEST A PERIOD OF SUNSHINE DURING THE EARLY AFTERNOON BEFORE THE REDEVELOPMENT OF CONSIDERABLE CLOUDINESS TAKES PLACE WITH INCREASING MID-LEVEL MOISTURE. WILL AT LEAST MENTION PARTLY SUNNY EARLY ALONG AND SOUTH OF I 94...WITH A BRIEF PERIOD OF PARTLY SUNNY CONDITIONS EVEN POSSIBLE ALONG M 59 EARLY IN THE AFTERNOON. THE EXPECTED SUN SHOULD HELP HIGHS REACH CURRENT MAXES OVER THE FAR SOUTHEAST...BUT WILL TWEAK HIGHS DOWN JUST A TOUCH ESPECIALLY OVER THE NORTHERN SAGINAW VALLEY WHERE MORE CLOUDS AND THE THREAT OF LIGHT SNOW SHOULD KEEP MAXES BELOW FREEZING. COORD WITH GRR. COMMENTS WELCOME. .DTX...NONE. DJF mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1025 AM EST WED JAN 12 2000 SURFACE OBS AND RADAR TRENDS SHOW SNOW CONTINUING TO DEVELOP IN WI...AND SPREADING EAST. THIS PRECIPITATION LINES UP WELL WITH THE RUC ISENTROPIC 290K MOISTURE FIELDS. THIS AFTERNOON...SNOW SHOULD SPREAD INTO MY NORTHERN COUNTIES. ACCUMULATIONS OF AROUND AN INCH POSSIBLE. THIS WILL INCLUDE FROM OCEANA TO ISABELLA...NORTH. THEN FOR TONIGHT...MESO ETA AND LATEST CANADIAN RUN SUGGEST STEADIER SNOW TO MOVE INTO SW LOWER MI. WILL ADD LIKELY OR BETTER PROBABILITIES OF SNOW AND OVERNIGHT ACCUMULATIONS 1 TO 3 INCHES...MAINLY NORTH OF I94. THIS SYSTEM COULD EASILY PRODUCE MORE SNOW THAN I AM PUTTING IN THE ZONES. HIGH SURFACE DEPOINT AIR LIFTING UP THROUGH THE LOWER MISSISSIPPI VALLEY...WILL FEED INTO THE SYSTEM. TIMING OF THE ARRIVAL OF THE MOISTURE IS CRITICAL TO HOW MUCH SNOW IT PRODUCES FOR SW LOWER MI. CONSIDERING NEW COMPUTER RUNS ARE COMING IN AT THIS TIME...WILL NOT TAKE ANY SIGNIFICANT JUMPS WITH THE FORECAST. HOWEVER...A GENERAL 1 TO 3 INCHES IS LIKELY...WITH THIS SYSTEM. ZONES OUT BY 1545Z .GRR...NONE. mi WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION NATIONAL WEATHER SERVICE MISSOULA MT 930 AM MST WED JAN 12 2000 WESTERN MT AND NORTH CENTRAL ID STILL UNDER INFLUENCE OF UNSTABLE AIR MASS FOR CONTINUED SNOW SHOWERS TODAY. SOME CONCERN ON STRENGTH OF SHORTWAVE ALONG 135W TAPPING POWERFUL JET STREAM AND COLD AIR ALOFT THIS MORNING. NEW MODELS DO NOT SHOW MUCH SIGNIFICANCE WITH THIS FEATURE...ALTHOUGH PRIOR NGM/MESOETA AND RUC INDICATE A WAVE AND HIGHER RH ACROSS NORTHERN ID/NORTHWEST MT LATER TONIGHT. ETA SHOWS A 150KT JET CORE MOVING NORTHWARD ACROSS OR BY 12Z WITH WEAK WARM ADVECTION OVERRUNNING MAINLY FOR NORTHERN COUNTIES. WILL WATCH THIS DEVELOPMENT FOR INCLUSION IN AFTERNOON PACKAGE. STRONGER SHORTWAVE WEST OF 150W APPROACHES COAST THURSDAY NIGHT. BETTER WAA AND JET DYNAMICS MAY BRING HEAVY SNOWS FOR NORTHWEST MT INTO FRIDAY MORNING. WILL CONSIDER HIGHLIGHTS FOR THIS AREA. NO UPDATES TO MORNING ZONES. BOLDT mt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 245 AM CST WED JAN 12 2000 TEMPERATURES WILL BE THE MAIN PROBLEM AGAIN TODAY. HIGHS YESTERDAY WERE NOT AS WARM AS EXPECTED...DUE TO THE MID LEVEL CLOUD COVER LINGERING LONGER AND BEING RATHER THICK. IN ADDITION...MIXING WAS NOT VERY GOOD SINCE THE WIND WAS SELY...RATHER THAN FROM THE S. IR AND WATER VAPOR STLT IMAGERY INDICATED THAT SEVERAL PIECES OF SHORTWAVE ENERGY WERE MOVING EAST FROM MT AND WY INTO THE DKTS EARLY THIS MORNING. MAIN VORTEX OVER THE GULF OF AK APPEARED TO BE DROPPING SWWD AS HEIGHTS CONTD TO FALL OUT NEAR 150/160W. LATEST SFC ANLYS SHOWED A LOW PRES CENTER OVER NWRN KS...WITH A WARM FRONT EXTENDING INTO SRN MO. SECOND FRONT WITH MODIFIED ARCTIC AIR TO THE N... STRETCHED STRETCHED FROM NRN IA...ACROSS SERN SD...TO NEAR VTN AND BFF...THEN NWWD FROM THERE. BEST PRES FALLS WERE OVER SRN KS AND NRN OK. THERE ARE SOME MAJOR DIFFERENCES IN HOW THE MODELS HANDLE THE SFC LOW AND THE COLDER AIR OVER THE NRN PLAINS. THE ETA IS THE FARTHEST S WITH THE LOW...AND CONSEQUENTLY COLDER THAN THE NGM OR AVN. HOWEVER NONE OF THE PREVIOUS MODELS DID A GOOD JOB WHEN COMPARED WITH THE 06Z ANLYS. THE LATEST RUC MODEL OUTPUT SUGGESTS THAT THE ETA MAY VERIFY BEST AT 18Z... BUT IT WILL PROBABLY BE TOO FAR S. THERE IS QUITE A DIFFERENCE IN THE AVN AND NGM MOS IN OUR AREA TODAY...ABOUT 6 TO 10 DEGREES F. WILL BE FAVORING THE COLDER AVN TODAY...WHICH MAY NOT BE COLD ENOUGH. EXPECT ABOUT A 20 DEGREE RANGE OF TEMPS FROM THE NRN PART OF THE AREA...NEAR THE SD BORDER TO THE SRN PART OF THE AREA NEAR THE KS BORDER. FOR TNGT AND THURSDAY...COLD AIR WILL SAG SOUTH AS THE SHORTWAVE ENERGY PASSES AND HIGH PRES BUILDS IN BY 12Z THURSDAY. HEIGHTS INCREASE ALOFT DURING THE DAY...BUT LOW LEVEL FLOW AND TEMPS WILL BE INFLUENCED BY THE COLD HIGH PRES OFF TO OUR EAST. GUIDANCE TEMPS LOOK TOO WARM OVER ERN NE AND SWRN IA...SO WILL UNDERCUT SLIGHTLY. NEW MRF SHOWS TROFS AT 500 MB NEAR 140W AND 70W...AND RIDGING OVER THE CNTRL U.S. SO THERE WILL BE LITTLE OR NO CHANGES MADE TO THE PREVIOUS 3-5 DAY FCST. THE FIRST DRAFT OF THE WORK ZONES WAS JUST SENT. .OMA...NONE MILLER ne AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORMAN OK 955 PM CST TUE JAN 11 2000 SATELLITE IMAGES SHOW MOST CONCENTRATED AREA OF HIGH CLOUDS IS ACROSS THE NORTHWEST TONIGHT WITH CLOUDS THINNING WITH TIME. LOOKS LIKE CLEAR TO MOST CLEAR WILL BE OK FOR TONIGHT. SURFACE TROUGH ACROSS PANHANDLE THIS EVENING WILL SHIFT EASTWARD OVERNIGHT WITH GRADIENT REMAINING FAIRLY WEAK. A LOOK AT THE LATEST RUC SHOWS SURFACE DEWPOINT NEAR 50 DEGREES APPROACHING FAR SOUTHEAST COUNTIES BY 12Z WITH NEW ETA ABOUT 5 TO 7 DEGREES LOWER. WITH LIGHT WINDS AND CLEAR SKIES...SURFACE TEMPERATURES WILL DROP INTO THE LOWER 40S BEFORE SURFACE MOISTURE INCREASES NEAR SUNRISE. WILL RAISE OVERNIGHT LOWS ACROSS PARTS OF SOUTHEAST COUNTIES AND MAY MENTION PATCHY FOG POSSIBLE AROUND SUNRISE. .OUN... OK...NONE. TX...NONE. 6 ok AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE LUBBOCK TX 1058 AM CST WED JAN 12 2000 WIND SPEEDS ARE QUITE A BIT STRONGER THAN EXPECTED OVER THE AREA THIS MORNING. TUCUMCARI PROFILER SHOWS 50 KNOT WESTERLY WIND RIGHT OFF THE SURFACE WHILE JAYTON SHOWS 30 KNOTS. RUC/MESOETA MODELS SHOW 70H GRADIENT TIGHT THIS MORNING BUT RELAXING DURING THE AFTERNOON. WILL RAISE WIND SPEEDS ACROSS THE AREA AS WELL AS BUMP THE TEMPERATURES UP A CATEGORY. EXPECT TO SEE RECORD HIGH TEMPERATURE AT LUBBOCK TODAY. .LBB...NONE. TINSLEY tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE COLUMBIA SC 120 PM WED JAN 12 2000 WEAK RIDGE OF HIGH PRESSURE AT THE SURFACE WILL CONTINUE OVER SOUTH CAROLINA THIS AFTERNOON. RUC MODEL TRIES TO INCREASE SOUTH TO SOUTHWEST WINDFLOW AND BRING ENOUGH WAA INTO THE STATE TO INCREASE TEMPERATURES INTO THE LOWER 70S. 0819Z ACARS SOUNDING FOR CAE ALSO GIVES THE LOWER 70S. HOWEVER...CURRENT WINDS ARE LIGHT AND VARIABLE AND MESOETA KEEPS WIND FLOW FAIRLY LIGHT ALTHOUGH MODEL SHIFTS WINDS INTO A SOUTHERLY DIRECTION. BELIEVE LIGHT AND VARIABLE WINDS WILL CONTINUE AND HIGHS WILL GENERALLY REMAIN BELOW THE 70 DEGREE MARK. SO WILL NOT CHANGE FORECAST HIGHS AND WILL KEEP LIGHT AND VARIABLE WINDS. .CAE...NONE TTH sc TEXAS/OKLAHOMA PANHANDLES FORECAST DISCUSSION NATIONAL WEATHER SERVICE AMARILLO TX 1206 PM CST WED JAN 12 2000 UPDATED ZNS TO ADJUST WIND SPEEDS/DIRECTION. CURRENT OBS SUGGEST SFC RIDGE BUILDING SWRD QUICKLY ACROSS FA BEHIND EXITING SFC TROUGH. THIS IS BRINGING WINDS MORE NRLY WITH TIME. 15Z RUC BACKS THIS UP WITH N/NE WINDS ACROSS ALL OF FA BY 21Z THEN VEERING TO MORE E/SE DIRECTION THIS EVE. ALSO CONCERNED WITH TEMPS...MUCH COLDER AIR ACROSS CENTRAL PLAINS MAY GET TAPPED AND DRAWN SWRD BUT THAT A LATER CONCERN. IN MEAN TIME...TEMPS STRUGGLING TO GET OUT OF 50S ACROSS SW KS AND ERN OK PNHDL THIS MORNING SO ALSO TRIMMED HIGHS BACK SOME THERE. .AMA... TX...NONE. OK...NONE. COBB tx