AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON 830 PM EST SUN FEB 27 2000 COLD FRONT PUSHING INTO WRN PART OF AREA NOW. RUC AND 18Z ETA SHOW THE FRONT SLOWING AS IT MOVES E. STRG VORT MAX AND GOOD DIVG ALOFT WL HELP TO DEVELOP A WEAK IMPULSE ON FNT WHICH IS EVIDENT NOW BY A WEAK LOW IN NW MD. THIS WL HELP TO HOLD PRECIP LONGER OVR ERN PART OF AREA. OVR THE W PRECIP WL END BY MIDN FARTHER E LATE. MODELS ALL SHOW NW WINDS DEVELOPING LATER TNGT WITH RAPID CLRG. CURRENT LAMP FCST CLRG ARND 09Z IN THE ERN PART OF AREA QUICKLY AFTER RAIN ENDS. THIS SEEMS REASONABLE AND WL ADD PARTIAL CLEARING TOWARD MRNG TO ZONES. CURRENT TEMPS SEEM REASONABLE IN THE 40S AS NOW STRG CAA UNTIL LATE TNGT AND TEMPS IN 40S WL BACK INTO OH. MAY HAVE MORE SUN ON MON BUT WL NOT CHG FOR NOW. .LWX...NONE. JAB md AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON 1050 AM EST SUN FEB 27 2000 WILL BE QUITE A CHANGEABLE DAY WITH EARLY MARINE STRATUS E OF THE BLUE RIDGE...VARYING DEGREES OF SUNSHINE...AND A THREAT OF SWRS AND TSTMS THIS AFTERNOON. THINK NHK WILL BE ONE TO WATCH...FOGGY AND 43 DEGS AT 10AM WITH A BREEZE OFF THE COLD BAY. WILL LIKELY GET INTO THE 60S WITH SUNSHINE THIS AFTERNOON. STRAT AND FOG IS ERODING. CNTIES IMMEDIATELY E OF THE BLUE RIDGE WILL BE LAST TO GO...INCLUDING HERE IN THE IAD AREA. BUT EVEN THAT SHOULD BE GONE BY 2PM. FRONT MOVING IN FROM THE WEST. 12Z RUC KEPT PRECIP IN THE MNTS THRU 00Z...BUT 12Z ETA SPREADS IT FURTHER E WITH .13 INCHES AT DCA BY 00Z...SO WILL KEEP POPS FOR ALL BUT ST MARY/S AND CALVERT IN THE FAR SE ZONES. POPS THIS AFTERNOON WILL RANGE FROM 30 OVER DCA AND BALTO...TO 80 IN THE POTOMAC HIGHLANDS. WILL ALSO KEEP TSTMS IN THE FORECAST EXCEPT IN THE FAR WEST. ALTHOUGH PRECIP ONLY SCT SHWRS ATTM...DAYTIME HEATING SHOULD INVIGORATE IT SOMEWHAT. STILL...WOULD ANTICIPATE ONLY SCT TSTMS AND MORE WIDESPREAD RAIN SHWRS. .LWX...NONE. STRONG md SOUTH CENTRAL AND SOUTHEAST MONTANA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BILLINGS MT 230 PM MST SUN FEB 27 2000 .MON AND TUE... TRICKY FORECAST WITH AVN AND RUC APPEARING TO HAVE BEST HANDLE ON SYSTEM APPROACHING COAST. RIDGING AND ASSOCIATED WARM AIR ADVECTION WILL MOVE EAST OF FORECAST AREA TONIGHT AS A SERIES OF WEAK SHORTWAVES EJECT FROM BASE OF TROUGH MOVING ON SHORE AND FLOW BECOMES SLIGHTLY CYCLONIC OVER STATE. STRONGEST SHORTWAVE PROGGED TO MOVE FROM CENTRAL NV THIS AFTERNOON AND STRENGTHEN OVER SOUTHWEST MONTANA TONIGHT AS IT BEGINS TO PHASE WITH SHORTWAVE OVER ALBERTA. MODELS PROG LEE SIDE SURFACE DEVELOPMENT ASSOCIATED WITH THIS SYSTEM...AND LOOKING AT CROSS SECTIONS STRONG MID LEVEL VERTICAL MOTION WILL BE COMBATING DOWNSLOPE GRADIENTS. FAVORING RUC/AVN SOLUTION FOR TONIGHT WILL LIMIT DOWNSLOPE INITIALLY AND RUC SEEMS TO BE BEST PROG FOR LOCATIONS OF SURFACE FEATURES AT 06Z WHEN LOOKING AT POSITIONS OF JET COUPLETS. THUS WILL HAVE SCATTERED POPS FOR TONIGHT IN WESTERN 2/3 OF FORECAST AREA TONIGHT AND WILL MENTION MIXED PRECIP AS TEMPS ARE WARM ENOUGH ALOFT FOR FREEZING PRECIP POSSIBILITIES. FOR MONDAY TROUGH AXIS CROSSES STATE FOR SOME INSTABILITY WITH BEST LAPSE RATES DEVELOPING OVER WYOMING. DRY ACROSS FORECAST AREA MONDAY NIGHT AND EASTERN SECTIONS ON TUESDAY AS SOUTHERN MONTANA WILL BE BETWEEN SYSTEMS. APPROACH OF ANOTHER PACIFIC STORM SYSTEM WILL SPREAD MOISTURE TOWARDS WESTERN AND CENTRAL SECTIONS ON TUESDAY...AND KEEP FORECAST INTERESTING IN THE EXTENDED. BORSUM .WED...THU...AND FRI... ALL EXTENDED MODELS...MRF...NOGAPS...ECMWF...INDICATE AN UNSETTLED WX PATTERN THROUGH DAY 5. AVN HINTS AT A SCENARIO SIMILAR TO THIS PAST FRI WITH SFC LOW OVER NC WY AND MOISTURE STREAMING IN FROM THE WEST. SFC LOW HERE WOULD ENSURE ANOTHER GOOD SATURATION EVENT YET MRF HAS LOW FURTHER NORTH WHICH WOULD STILL BRING PRECIP TO THE REGION BUT NOT AS MUCH. MRF THEN GOES DRY INTO DAY 5 BUT REMAINING MODELS KEEP A HINT OF ACTIVITY TO THE WEST WITH CLOSED LOW TRAVERSING TO THE SOUTH. WITH THIS IN MIND WILL TREND FCST NUMBERS WELL BELOW MRF BASED GUIDANCE AND KEEP A CHANCE OF SHOWERS FOR DAYS 3 & 4 AND DRY FOR DAY 5. SPRINGER BIL EBWWE 029/051 028/051 028/045 028/050 028/050 593202 54 LVM EBWWE 027/052 026/052 026/047 024/052 024/052 594303 54 HDN EBWWE 026/052 027/052 027/045 027/050 027/050 593202 54 MLS EBWWE 025/048 026/048 026/047 026/052 026/052 592200 54 4BQ EBWWE 023/046 026/046 026/046 026/051 026/051 592200 54 BHK EBWWE 021/045 024/045 024/044 024/049 024/049 592200 54 SHR EBWWE 025/047 024/047 024/044 024/049 024/049 593300 54 mt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BINGHAMTON NY 950 AM EST SUN FEB 27 2000 MRNG VSBL PICS SHOW PLENTY OF BREAKS IN LOW CLOUDS WITH THE EXCEPTION (OF COURSE) AROUND BROOME COUNTY. WHERE IT IS SUNNY TEMPS ARE RAPIDLY RISING AND HELPING TO MIX DOWN GUSTY SWLY WINDS...ESPECIALLY ALONG THE LAKE PLAIN. IN SERN ZNS A LIGHT SELY COMPONENT PROVODING SOME WEAK OROGRAPHIC LIFT AND KEEPING COLD AIR AND LOW CLDS LOCKED IN. THIS AREA THE LEAST LIEKLY TO BREAK UP TODAY AND WILL KEEP LOW CLOUDS IN FOR AFTN. ELSEWHERE AM PLAYING A PTLY SUNNY SCENARIO FOR MUCH OF THE AFTN...EVEN HERE IN BROOME AND ADJACENT COUNTIES. LAST FEW PICS SHOW SOME BREAKS IN DECK OVR SERN BROOME COUNTY SO AM HOPING THIS WILL CONT. KBUF RADAR SHOWS NARROW BAND OF BKN SHWRS ENTERING WRN PA/NY ATTM. EXTRAPOLATION OF LEADING EDGE HAS IT INTO WRN CWA TOWARD MID AFTN. THIS BAND HAS BEEN SHOWING SIGNS OF BREAKING UP AS IT MOVES E SO LEADING EDGE MAY JUST BE COMPRISED OF SCT LGT SHWRS BY THE TIME IT ARRIVES THIS AFTN. WILL KEEP SHWRS IN FOR CNTRL ZNS FOR LATE AFTN. 12Z RUC HAS LEADING EDGE OF PCPN JUST INTO CNTRL ZNS BY 00Z SO FEEL IT WON'T MAKE IT TO EXTRM ERN ZNS TIL THIS EVE AND WILL TAKE IT OUT THERE. TEMPS WILL BE TRICKY DEPENDING ON JUST HOW MUCH SUN ANY PLACE GETS. HAVE LOWERED TEMPS SLIGHTLY IN SYR AREA ONLY BECAUSE THEY ARE STILL SHOWING A LIGHT ERLY FLOW AND IF THAT HOLDS LONG ENOUGH IT WILL TEMPER THE RISE IN TEMPS. WILL CONT FLOOD WATCH FOR TNGT BUT REALLY DON'T HAVE MUCH TO ADD AS THINGS ARE PRETTY QUIET FOR NOW. .BGM...FLOOD WATCH TONIGHT... NYZ044>046-055>057-062-PAZ038>040-043-044-047-048 HOLMES ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 935 AM EST SUN FEB 27 2000 LATEST SAT IMAGRY INDICATES PCPN MOVG A BIT FASTER THAN 00Z MODELS PROGGED. LATEST RUC RH CLOSER TO REALTY. DEWPTS ACROSS THE FA HAVE RISEN TO ARND 60. INSOLATION B4 CLDINESS MOVES INTO THE REGION WILL HELP BOOST TEMPS INTO THE LOW TO MID 70S. CONVECTIVE PARAMETERS ...LIS AND CAPE STILL SOMEWHAT MARGINAL BUT WILL CONTINUE TO INCLUDE TSRA. MAY INCREASE POPS BY 10-20 ACROSS MOST SUTHERN AND/OR WESTERN ZNS. WILL WAIT UNTIL FCST ISSUANCE TIME TO DECIDE. ISOLTD SVR POTENTIAL STILL POSSIBLE BUT NOT WIDESPREAD ENUF TO INCLUDE IN ZNS. MAY UPDATE OPU LATR TODAY TO REFLECT THE PSBLTY. CURRNT FCSTD TEMPS LOOK ON LINE BASED ON CURRENT OBS AND MORNING SNDINGS. CWF...PG TO INCREASE THIS AFTN WHICH WILL ALLOW SPEEDS TO REACH 15-20 KTS WITH A FEW HIGHER GUSTS. MAY TWEAK PCPN PORTION ...OTHERWISE ALL LOOKS AOK. .ILM...NONE. DCH nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 839 PM EST SUN FEB 27 2000 LATEST SURFACE ANALYSIS INDICATES COLD FRONT CURRENTLY ALIGNED NORTHEAST TO SOUTHWEST ACROSS OUR CWFA. FRONT ITSELF HAS PASSED GSP WITHIN THE PAST HOUR. REDEVELOPING SHOWERS AHEAD OF THIS FEATURE HOLDING TOGETHER...BUT MAY BE EAST OF CWFA BY ISSUANCE TIME. WATER VAPOR IMAGERY SHOWS VORT CENTER MAKING ITS CLOSEST APPROACH TO THE CWFA AND SOME SUGGESTION THAT IT IS ALREADY PULLING NORTHWARD. IR LOOP WITH ITS LACK OF LOW LEVEL CLOUDINESS ACROSS EAST TENNESSEE SUPPORTS THE CLEARING TREND AS CURRENTLY ADVERTISED IN ZONES. WILL KEEP AN EYE ON AFOREMENTIONED SHOWERS...BUT PLAN TO REMOVE PRECIP MENTION IN ALL ZONES WITH EVENING UPDATE. 21Z RUC SUGGESTS A STEADY ADVECTION OF DRIER AIR INTO ALL OF THE CWFA OVERNIGHT...BUT THESE LOWER DEWPOINTS MAY NOT REACH THE CHARLOTTE AREA AND ITS SURROUNDING ZONES UNTIL AFTER DAYBREAK. WILL TWEAK TEMPERATURES IN THE EASTERN MOST ZONES...BUT DO NOT PLAN ANY OTHER TEMPERATURE CHANGES. COLD ADVECTION UNDERWAY IN THE MOUNTAINS WITH ASHEVILLE SHOWING A SUSTAINED WIND AT 20 KTS. WILL RAISE WIND SPEEDS IN THE MOUNTAIN ZONES OVERNIGHT...GOING 15 TO 25 AND GUSTY AND REQURING A WIND ADVISORY FOR AREA LAKES THERE. .GSP...WIND ADVISORY FOR MOUNTAIN LAKES OVERNIGHT. BURRUS sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON SC 211 PM EST SUN FEB 27 2000 SFC COLD FRONT WILL PUSH OFFSHORE AFTER MIDNIGHT WITH TRANQUIL WEATHER EXPECTED FOR MUCH OF THE UPCOMING WEEK. SHORT TERM...SCT TSTMS REMAINED CONFINED TO SRN GEORGIA AND NRN FLORIDA WHERE SFC DEW POINTS ARE IN THE LOWER 60S. RUC INDICATES H85 THETA RIDGING WILL CONTINUE TO NOSE NE THRU OUR CWFA UNTIL EXITING THE COAST AROUND MIDNIGHT. MIXING RATIOS AND THETA VALUES ARE FCST TO WEAKEN LATER TODAY...BUT EXPECT ISOLD/WDLY SCT TSTMS EMBEDDED WITHIN THE PREFRONTAL RAIN BAND TO OCCUR AS VORT LOBE SWINGS BY. BULK OF THE RNFL SHOULD BE ALG/OFF THE S CAROLINA COAST AROUND MIDNIGHT WITH THE ONSET OF NVA AND CLEARING SKIES LATER TONIGHT. FCST MAX TEMPS ON MON FROM 12Z ETA THICKNESS PROGS INDICATE 65-70 N TO THE LOWER 70S S WHICH IS CLOSER TO FWC GUIDANCE AND WILL FOLLOW. CAA NOT VERY STRONG AND LOCATIONS THAT FAIL TO REACH 70 MON SHOULD HAVE NO TROUBLE REACHING 70 THE REMAINDER OF THE WEEK. H85 HIGH PRES WILL SETTLE OVER SE GEORGIA MON NIGHT AND GOOD RADIATIONAL COOLING IS LIKELY. EXTENDED...NOGAPS IS MORE PROGRESSIVE THAN THE MRF WITH THE NEXT SYSTEM WHICH MAY PAN OUT CONSIDERING THE PAST FEW FRONTS. ON FRI ...CANNOT RULE OUT A FEW CSTL SHOWERS IN MARINE CONVERGENCE AROUND THE BACKSIDE OF THE ATLC RIDGE. WILL INDICATE A PARTLY CLOUDY DAY 5 WITH NO MENTION OF RAIN FOR NOW. CWF...AS WAS EXPECTED...WINDS HAVING A TUFF TIME MIXING DOWN OVER THE RELATIVELY COOLER WATER. WIND SPEEDS STILL ON THE ORDER OF 10- 15 KT OVER MOST OF THE AREA...BUT PROBABLY A LTL HIER IN OFFSHORE GA WATERS. MOST OF THE H85 JET WL PASS N OF THE AREA TNGT. A CD FNT WL MOVE THRU THE WATERS LATE TNGT WITH WINDS VEERING QUICKLY TO THE NW- N. FOR MON...SUM CAA AND A LATE MORNING SURGE ARE LIKELY WITH WINDS 15-20 KT FOR A TIME...DIMINISHING SOMEWHAT IN THE AFT. ANOTHER SURGE IS EXPECTED LATE MON NGT AND EARLY TUE AS WINDS BECOME NE. WL KEEP SCEC HEADER OUT FOR OFFSHORE GA THIS PKG. THE HEADLINE MAY BE NEEDED FOR NEARSHORE GA WATERS LATE TNGT THRU MON MORN. FOR SC WATERS...WL INC WINDS TO 15-20 LATE TNGT...THEN 20 KT DIM TO 15 KT FOR MON. SEAS 5 FT OR LESS THRU THE PD. CHS UU 048/068 039/071 043 2470000 SAV UU 048/070 036/073 041 2450000 CHL UU 053/067 045/068 047 2470000 NBC UU 049/068 041/072 043 2470000 .CHS... SC...NONE. GA...NONE. RVT/TJR sc AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA NATIONAL WEATHER SERVICE ABERDEEN SD 835 PM CST SUN FEB 27 2000 LATEST RUC SHOWS SFC PRES GRADIENT TIGHTENING UP QUITE A BIT THROUGH THE NIGHTTIME AND THUSLY SHOWS SE WINDS INCREASING. BELIEVE THE WINDS WILL DO JUST THAT THROUGH THE NIGHT AND BECOME BREEZY OVER THE ENTIRE AREA. SATELLITE AND SFC OBS SHOWING A LOT OF DENSE HIGH LEVEL CLOUDS OVERSPREADING MUCH OF THE CWA THIS EVENING. THEREFORE...SKIES WILL BE OR BECOME MOSTLY CLOUDY OVER ALL OF THE CWA EXCEPT FOR C SD. THE SE WINDS WILL ALSO BRING IN WARMER AIR TONIGHT. THEREFORE...WITH INCREASING SE WINDS...WAA...AND HIGH CLOUD COVER...TEMPS WILL NOT FALL OFF VERY MUCH. UPDATED FORECAST TO MAKE SEVERAL CHANGES TO ALL AREAS. .ABR...NONE MOHR sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 825 PM EST SUN FEB 27 2000 LATEST RUC AND MESO-ETA DEPICT LOW- TO MID-LEVEL VORTICITY HANGING OVER NORTHERN TENNESSEE AND SOUTHWEST VIRGINIA BEYOND 06Z...BEHIND MAIN UPPER-LEVEL SYSTEM POSITIONED MUCH FARTHER NORTHEAST. HOWEVER...SEE LITTLE CONSEQUENCE TO THIS AS VERY DEEP ATMOSPHERIC LAYER IS ON THE BACK SIDE OF THE MAIN SYSTEM. PRECIPITATION ECHOES HAVE DEPARTED THE NORTHERN FORECAST AREA...SO WILL DO AN UPDATE IN THIS REGION...INCLUDING THE MENTION FOR A DECREASING CLOUD TREND. AS FAR AS OVERNIGHT MINS...THEY LOOK ON TRACK CONSIDERING CLOUD TRENDS. .MRX... NC...NONE. TN...NONE. VA...NONE. DM tn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 1049 AM EST SUN FEB 27 2000 CF TO MOVE EAST ACRS THE GREAT LKS REGION AND INTO THE ST LAW VLY TODAY...THEN ACRS THE FA TONITE. PREFER 00Z AVN SOLN BASED ON 12Z POSN OF FRONT/PCPN. AVN NOT STRONG ENUFF WITH SFC LOW IN NORTHERN ONT THOUGH. WK WAVE OF LOW PRESS MAY DEVELOP ALONG THE FRONT LATER TONITE...ENHANCING ANY QPF THAT FALLS. UPR LVL TROF TO PASS THRU THE GREAT LKS REGION TODAY AND TONITE. PW VALUES ASSOCIATED WITH FRONT TO BE AROUND 0.75". 09Z RUC SHOWS SOUTH WINDS INCREASING TODAY (ESPECIALLY IN NORTHERN NY). TEMPS TO GET UP INTO THE 50S FROM THE CHAMP VLY WESTWARD AND INTO THE 40S IN EASTERN VT. GIVEN CURRENT TRENDS...THESE TEMPS PROLLY STILL TOO COLD FOR TODAY. H85 MOISTURE TO INCREASE ACRS NORTHERN NY TODAY WITH THE BEST CHC FOR PCPN IN THE ST LAW VLY. RUC SHOWS LOWEST LVL MOISTURE STARTING TO DRY UP IN EASTERN VT (WHERE LOW CLDS HAVE CONTINUED TO HANG TUFF) AFTER 18Z. CT VLY WILL HAVE THE HARDEST TIME CLEARING TODAY. RUC KEEPS UPR LVL DYNAMIX AND ANY MEASURABLE PCPN TO THE WEST OF THE FA TODAY. CURRENT SAT PIX/RADAR TRENDS SHOW CLDS/PCPN ASSOCIATED WITH CF MOVING MOSTLY NORTHEASTWARD ATTM. EXTRAPOLATION OF CURRENT PCPN BRINGS IT INTO THE ST LAW VLY BY AROUND 20Z AND THE ADIRONDACKS BY AROUND 22- 23Z. HAVE REGROUPED MORNING UPDATE ZONE GROUPINGS BASED ON CURRENT CLD COVER TRENDS. HAVE TWEAKED GOING TEMP/WIND FORECAST FOR TODAY BASED ON CURRENT OBS TRENDS. RECORD HI TEMPS TO BE EXCEEDED TODAY EASILY IN MOST LOCATIONS THAT WE KEEP TRACK OF. LOOK TO RERBTV LATER FOR ANY DETAILS. HYDRO-WISE...A FEW RIVER GAGES ARE WITHIN 2-3' OF FS ATTM. RIVER UNDERWENT SOME PRETTY GOOD RISES FROM YESTERDAY/S SNOWMELT. WITH MORE SNOWMELT TODAY THAN YESTERDAY AND IMPENDING RAINFALL TONIGHT FEEL THAT AN FFA ACRS ALL ZONES WOULD BE WARRANTED FOR THE REST OF TODAY AND TONIGHT. BEST CHC FOR ANY FLOODING PROBLEMS WILL BE WHERE IT/LL BE GETTING THE WARMEST TODAY (NORTHERN NY). SE VT WILL STAY THE COLDEST AND SHOULDN/T SEE AS MANY FLOODING DIFFICULTIES. ICE JAMS WILL BE A DEFINITE THREAT INTO THE EVENING HOURS. WORK ZONES GONE. WILL UPDATE ADMBTV FOR FFA AND HAVE FINAL ISSUANCE OF ZFP OUT BY 11 AM. .BTV...FFA NYZ026>031-034-035-VTZ001>012 THROUGH TONIGHT. MURRAY vt SOUTHEAST ARIZONA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE TUCSON AZ 303 AM MST MON FEB 28 2000 SYNOPSIS...A SERIES OF WEAKENING PACIFIC STORM SYSTEMS WILL RACE ACROSS NORTHERN ARIZONA THIS WEEK. THE FIRST ONE CROSSING THE AREA TODAY WILL BRING MUCH COOLER TEMPERATURES AND INCREASED WIND...BUT ANY PRECIPITATION WILL BE LIGHT AND CONFINED TO THE WHITE MOUNTAINS. ANOTHER FAST-MOVING SYSTEM WILL ALSO PASS TO THE NORTH ON WEDNESDAY...WITH YET ANOTHER ONE APPROACHING THE REGION ON FRIDAY. DISCUSSION...SUSTAINED WIND OF 21KTS AT KYUM AND SOME GUSTS OF 35-45 ON HIGH ELEVATION RAWS SITES ARE CONFIRMING EVEN STRONGER WINDS INDICATED ON MM5 AND 09Z RUC. BOTH BRING 850MB WINDS OVER THE E CWA TO 25KTS JUST AFTER SUNRISE AND HOLD THEM THERE FOR MUCH OF THE DAY WITH 700MB WINDS APPROACHING 50KTS. WITH PEAK COLD ADVECTION OCCURING DURING DAYLIGHT HOURS, THERE'S A BETTER CHANCE FOR CONVECTIVE OVERTURNING. WE'LL GO AHEAD AND ISSUE AN ADVISORY FOR THE E CWA THRU 600PM AND MENTION THE POSSIBILITY OF SOME BLOWING DUST. PYTLAK .TWC...WIND ADVISORY TODAY ZONES 19/30/35. az AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 1015 AM CST MON FEB 28 2000 FORECAST HAS BEEN UPDATED TO INCREASE TEMPERATURES. 12Z ANALYSIS SHOWS 925/850 MB TEMPERATURE SURGE FROM SOUTH AND LATEST RUC MODEL FORECAST PUSHES TEMPERATURES WELL INTO 50S. BIG QUESTION THOUGH IS HOW HIGH WINDS WILL GO. BOUNDARY LAYER FORECAST SHOWS 40 KNOTS JUST OFF SURFACE AND THIS IS SUPPORTED BY LATEST PROFILERS. ISALLOBARIC GRADIENT WILL KEEP WINDS MORE SERLY AND SURFACE GRADIENT DOES NOT CHANGE MUCH. FORECAST CURRENTLY KEEPS WIND BELOW ADVISORY CRITERIA...BUT COMBINATION OF PRESSURE AND ISALLOBARIC GRADIENT COULD PUSH WIND UP...HOWEVER NO APPARENT SOURCE OF SUBSIDENCE/ DOWNWARD MOMENTUM TRANSFER IN UPPER LEVEL FORECASTS. .MSP...NONE SCOTT mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 1055 AM EST MON FEB 28 2000 BTV SH COORD WITH "THE BUF" AND GYX ABOUT FLOOD PROBLEMS...THANX FOR THE INFO. CF TO MOVE OFF THE COAST TODAY AS A WK WAVE OF LOW PRESS RIDES ALONG IT. HI PRESS RIDGE TO BUILD ACRS THE GREAT LKS REGION TODAY AND TONITE...NOSING INTO THE ST LAW VLY LATE TONITE. NORTHERLY FLOW ALOFT TO DEVELOP ACRS THE FA INTO TONITE. PREFER 00Z ETA SOLN BASED ON CURRENT SFC PRESS AND PCPN TRENDS. 09Z RUC SHOWS W-NW SFC FLOW ACRS THE FA TODAY. TEMPERATURE MAXES HAVE ALREADY BEEN REACHED TODAY AS TEMPS WILL BE FALLING THROUGH THE 30S FOR THE REST OF TODAY. 14Z LAMP DATA INDICATES KSLK WILL BE FALLING INTO THE UPR 20S BY LATER TODAY. PLENTY OF LOW-LVL MOISTURE TO HANG AROUND ACRS THE FA THROUGH TONITE (ESPECIALLY IN EASTERN VT) BEHIND THE FRONT. UPR TROF TO MOVE THRU THE FA TODAY AS WELL...ALL SPELLING OUT THE CHC FOR SHOWERS INTO THE OVERNITE PERIOD. RUC INDICATES BEST CHC FOR STEADY PCPN WILL BE BETWEEN 15Z AND 18Z TODAY. MEASURABLE PCPN WILL BE SCT IN NATURE AFTER THAT. RUC P-TYPE SHOWS SN IN THE NORTHERN ADIRONDACKS AND RA TO SN (ESPECIALLY IN THE HIR TRRN) ELSEWHERE TODAY. ALREADY HAVE HAD A FEW REPORTS OF A CHANGEOVER TO SN IN THE HIR TRRN OF THE GREEN MTNS AND CURRENT SFC TEMPS/DEW PTS SUPPORT SN IN THE NORTHERN ADIRONDACKS. FA TO BE UNDER H85 CAA TODAY WITH SOME WAA OCCURRING FROM THE NORTH OVRNITE TONITE. "COLDEST" (NOT REALLY THAT COLD AT ALL) COLD POOL AT H85 TO BE OVER THE REGION BY AROUND 06Z TONITE. HIGHEST LOW-LVL LAPSE RATES ACRS THE FA BETWEEN 18Z TODAY AND 06Z TONITE. SHSN TO CONTINUE (ESPECIALLY IN THE HIR TRRN) INTO THE OVERNITE PERIOD. HYDRO-WISE...IT/LL TAKE A WHILE FOR THE RIVERS TO "SOLIDIFY" WITH THE FALLING TEMPS TODAY. ICE JAMMING IN PROGRESS ALONG THE GREAT CHAZY... MISSISQUOI...LAMOILLE...AND CT RIVERS ATTM. HI WATER ALSO ALONG THE POULTNEY AND NEW HAVEN RIVERS AND THE OTTER CREEK...WITH MORE FLOODING LIKELY ALONG THOSE WATERWAYS BY LATER TODAY. FURTHER OUT WEST IN NY STATE...THE OSWEGATCHIE...THE RAQUETTE...AND THE SAINT REGIS RIVERS (WHICH USUALLY TAKE A LOOOOONG TIME TO RESPOND TO RAINFALL) ARE CONTINUING TO RISE. ALL THIS LEADS ME TO WANT TO EXTEND THE FFA THROUGH THE REST OF TODAY JUST TO BE SAFE...WHICH IS WHAT WE/LL DO. LOOK FOR FURTHER FLOOD STATEMENTS FOR ANY DETAILS. WORK ZONES AWAY. FINAL ZFP AFTER QUICK LOOK AT LATEST OBS. FYI...CWBZ (ST ANICET QB) IS REPORTING BOGUS TEMPS/DEW PTS ATTM...SO BEWARE. .BTV...FLOOD WATCH THRU REST OF TODAY NYZ026>031-034-035-VTZ001>012. MURRAY vt WESTERN COLORADO & EASTERN UTAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 240 AM MST MON FEB 28 2000 NEXT PROGRESSIVE SYSTEM PASSES THIS AFTERNOON. MOUNTAIN SNOWS LIKELY BUT WILL BE LESS THAN PREVIOUS SYSTEMS. NO HIGHLIGHTS PLANNED THIS MORNING...BUT SAN JUAN MOUNTAINS WILL GET CLOSE TO ADVISORY CRITERIA. CURRENTLY: AT 08Z SURFACE FRONT IS NOT DISTINCT...BUT SOMEWHERE NEAR WESTERN UTAH. GOES SOUNDER SHOWS GOOD INSTABILITY (T500 -28C) IN BOTTOM OF TROF WITH LTG STRIKES NORTH OF LAS VEGAS AT 07Z. BUT SATELLITE AND SFC OBS SHOW LIMITED MOISTURE AVAILABLE WITH THIS SYSTEM. LOCAL PREFRONTAL ENVIRONMENT IS MILD AND WINDY WITH 88D 11K MSL WINDS AT 50-60KTS AND DRAINAGE ENHANCED HERE AT GJT. HARD TO SEE A CLEAR FROPA THIS AFTERNOON BUT ALL MODELS HAVE ALL ZONES S-SW AT 18Z AND W AT 00Z. LACK OF STRONG FRONTAL DEFINITION INDICATIVE OF DISORGANIZATION WITH THIS SYSTEM. SLC DOES NOT SEE AN EFFICIENT STRUCTURE TO THIS SYSTEM AND I AGREE. MODEL SCENARIO IS THUS: PREFRONTAL MOISTURE IS LACKING BUT SOME WRINGING LIKELY ESPECIALLY IN THE OROGRAPHICALLY FAVORED SAN JUANS. 90-100KT JET NOSE POINTED AT CENTRAL MTNS BY 18Z WITH COLD POOL JUST BEHIND. THIS IS FURTHER NORTH THAN PREVIOUS SYSTEMS AND WILL NOT ASSIST THE SOUTHERN MTN SNOWS. SOME INSTABILITY JUST BEHIND THE JET...THOUGH THE 06Z RUC IS NOT AS UNSTABLE AS THE AVN. STILL SOME THUNDERSTORM IS LIKELY...CENTERED ON THE SOUTHERN ZONES. PRETROF WINDS TO BE GUSTY...BUT DIMINISH THIS LATE AFTERNOON WITH TROF PASSAGE. QUICK VEER TO NW TONIGHT. ISENTROPIC LIFT (300K SFC) SEEN 00Z-12Z TONIGHT FOR ALL BUT SOUTHERN SAN JUAN MTNS. STILL WITH LIMITED MOISTURE...EXPECT AMOUNTS TO NOT EXCEED ADVISORY CRITERIA EXCEPT IN LOCALLY FAVORED AREAS. NORTHERN SAN JUANS ESPECIALLY TELLURIDE MAY BE THE BIG WINNER IN THIS SYSTEM WITH ACCUMULATIONS IN BOTH SW AND NW FLOW. PRECIP OVER BY 12Z TUESDAY AS 500TEMPS WARM AND SHORTWAVE RIDGE AXIS IS OVERHEAD BY TUE AFTERNOON. NEXT SYSTEM...CURRENTLY NEAR 135/45 OFF THE OREGON COAST...BEGINS TO PRODUCE WARM ADVECTION LIGHT POPS AS EARLY AS TUESDAY NIGHT IN EASTERN UTAH. BEST POPS ON WED-EARLY THU. THIS SYSTEM PROGGED BY AVN/EC TO FURTHER SOUTH AND MORE CLOSED THAN CURRENT SYSTEM...THOUGH NOGAPS/CANADIAN ARE FASTER/MORE OPEN. NO CHANGE PLANNED TO TIMING OF PREVIOUS PACKAGE IN-BETWEEN DAY FRIDAY THOUGH TIMING IS PRECARIOUS. NEW MRF YIELDS NO SURPRISES...JUST THE NORMAL LARGE TIMING DIFFERENCES BEYOND DAY THREE. PROGRESSION CONTINUES WITH LOTS OF ENERGY ADVERTISED IN THE SOUTHERN BRANCH. TROF PASSAGES ADVERTISED FOR TODAY...THU...LATE WEEKEND. 99/RAMEY .GJT...NONE. EMERGENCY MANAGERS IN THE MOUNTAINS ON EASTERN UTAH AND WESTERN COLORADO SHOULD MAINTAIN A HEIGHTENED LEVEL OF WEATHER AWARENESS THIS AFTERNOON AND TONIGHT DUE TO AREAS OF BLOWING AND DRIFTING SNOW. OTHER EMERGENCY MANAGERS IN LOWER ELEVATIONS SHOULD MAINTAIN A NORMAL LEVEL OF WEATHER AWARENESS TODAY. co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KEY WEST FL 950 AM EST MON FEB 28 2000 CURRENTLY... VISIBLE SATELLITE AND SURFACE ANALYSIS PLACES A COLD FRONT JUST PAST MELBOURNE TO JUST PAST PUNTA GORDA AT 9 AM. A NARROW LOW LEVEL ROPE-LIKE CLOUD MARKS THIS BOUNDARY ON SATELLITE. THERE IS A WEAK SURFACE RIDGE AHEAD OF THE FRONT EXTENDING FROM THE EXTREME SE GULF OF MEXICO TO THE UPPER KEYS. AS A RESULT...WINDS AS REPORTED AT C-MAN STATIONS AND ISLAND SITES ARE N AT UPPER KEYS...NNE MID AND LOWER KEYS...NE AT DRY TORTUGAS. WIND SPEEDS OF COURSE ARE LIGHT...5-10 KT. 12Z KEY WEST SOUNDING SHOWED PRECIPITABLE WATER DOWN TO .77...A BIT DRIER THAN 24 HOURS AGO WITH MOISTURE STILL CONFINED TO THE LAYER BELOW 5 THSD FT. THERE IS ANOTHER NARROW LOW LEVEL CLOUD LINE...THIS ONE IN THE FLORIDA STRAITS PARALLELING THE KEYS FROM UPPER KEY LARGO TO SOUTH OF MARATHON. THIS APPEARS TO BE THE CONVERGENT LINE BETWEEN THE SURFACE RIDGE FROM THE GULF PRODUCING NORTH FLOW AND A MORE NORTHEAST OR EASTERLY FLOW PRODUCED BY THE ATLANTIC RIDGE. FIRST PERIOD FORECASTS... LOOKING AT LATEST RUC AND MESO-ETA OUTPUT...THE WEAK RIDGING ACROSS THE UPPER KEYS BREAKS DOWN BY THE LATTER PART OF TODAY. BOTH NEAR-TERM MODELS SHOW THE FRONT CONTINUING SE TO JUST NW OF THE KEYS BY 00Z WHERE IT MAY STALL THROUGH TONIGHT. AT ANY RATE... AS THE RIDGE WEAKENS EVEN MORE...A COL OR NEUTAL POINT AREA IS INDICATED BY THE MODELS OVER THE KEYS (MAINLY UPPER KEYS) BY LATE AFTERNOON. THUS...THE CURRENT MAINLY NNE FLOW MAY GO VARIABLE AS EXPECTED BY MID TO LATE AFTERNOON. THIS WILL BE INDICATED ON THE 1030 AM COASTAL MARINE. THE RUC/MESO-ETA ALSO SHOW LOW LEVEL CONVERGENCE AND SOME 850 MB OMEGA THIS AFTERNOON OVER THE SOUTHERN PENINSULA. THIS MAY LEAD TO SHOWERS WHICH COULD MIGRATE TOWARD THE KEYS...IN ADDITION TO ANY SMALL SHOWERS THAT MAY FORM NEAR OR OVER THE KEYS IN THE LIGHT WIND FLOW. SO...NO UPDATES ARE NEEDED TO THE PUBLIC ZONE FORECASTS. .EYW...NONE. CLB fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIAMI FL 915 AM EST MON FEB 28 2000 UPPER DYNAMICS HAVE SCOOTED TO THE NE OUT OVER THE ATLC AS PROGGED SO THE OVERNIGHT SLIGHT CHANCE OF SHOWERS HAS ABATED. NOW THE MAIN QUESTION IS WILL IT SHOWER TODAY? ENOUGH INGREDIENTS REMAIN IN THE PRESENT MIX TO KEEP CURRENT PACKAGE GOING WITH SOME MINOR CHANGES. EYW/MFL 12Z RAOBS INDICATING COOLING ALOFT AT MID LEVELS WHICH ARE DESTABILIZING THE ATMOSPHERE A LITTLE. 03Z MESOETA INDICATING SOME UPWARD OMEGA THOUGH WITHERING AS DAY GOES ON. EXPECT SEA BREEZE TO DEVELOP ON EACH COAST AND WITH WEAKENING FRONT OVER S CENTRAL PART OF FLA EXPECTED TO CONTINUE S MOVEMENT...LOW LEVEL CONVERGENCE DUE SEA BREEZES AND FRONT MEETING THE FORMER POSSIBLY ENOUGH FOR SOME- THING TO GENERATE. BUT....!!! FRONT LOSING STEAM AND 11Z RUC SHOWS DOWNWARD OMEGA. TBW 12Z ROAB INDICATING WARMING ALOFT AND ON NORTH FLOW ALOFT WILL ADVECT OVER S FLA NUKING INSTABILITY. THIS ALSO TO BE MULLED OVER. WILL UPDATE ZONES BUT NOT SURE OF FINAL PACKAGE AT THIS TIME. NO HIGHLIGHTS TO CWF ZONES SO NO SIGNIFICANT CHANGES. .MIA...NONE. fl