EAST CENTRAL FLORIDA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 832 PM EST MON MAR 27 2000 CURRENTLY...RUC INDICATES 110 KNOT 250 MB JET NOSING INTO EASTERN GULF. STRONG SHORTWAVE TROUGH AXIS WAS ROTATING ACROSS GEORGIA AND RESULTING IN IMPRESSIVE DIVERGENCE ALOFT. A FEW STRONG/SEVERE STORMS RACED EAST ACROSS THE AREA THIS EVENING BUT WITH LOW COVERAGE AS LOW LEVEL FOCUSING BOUNDARIES HAVE BEEN SPARSE AND DEEP MOISTURE SOMEWHAT LIMITED. OVERNIGHT...WILL FOLLOW TRENDS FOR THE NEXT HOUR OR SO BUT IT LOOKS LIKE AS THE SHORTWAVE PULLS AWAY TO THE EAST AND UPPER DIVERGENCE WEAKENS...POPS CAN BE TAPERED BACK FROM NORTH TO SOUTH. WILL NOT BE ABLE TO REMOVE POPS THOUGH FOR MOST AREAS...AS SOME SHOWERS ARE POSSIBLE UNTIL THE FRONT PASSES LATE. MARINE...STRONG GRADIENT OVER THE WATERS DUE TO STRONG SECONDARY LOW OVER NORTH CAROLINA. FRONT PROGGED TO PUSH INTO THE AREA LATE AND SLOW DOWN. DO NOT SEE ANYTHING MAJOR TO CHANGE IN CURRENT FORECAST. .MLB...SCA FLAGLER BEACH TO JUPITER INLET. FIRE WX WATCH TUESDAY AFTERNOON ZONES 041-044>046-053-058. AVIATION/FIRE WX...KELLY PUBLIC/MARINE...LASCODY fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON 956 PM EST MON MAR 27 2000 STDY RA HAS BN OCCURRING N OF SFC LOW THIS EVE. SFC LOW AT 02Z WAS LOCATED OVR SE VA. LATEST MESO ETA PROGS LOW TO MOV N WHILE RUC MOVS LOW NE. BASED ON 00Z 700 MB FLOW...APPRS MESO ETA HAS BTR HANDLE ON THIS FEATURE. THEREFORE...BASED ON MESO ETA TIMING...PCPN SHUD BE OUT OF THE FA BY 06Z. WL TWK ZONE WORDING TO REFLECT THIS TIMING. CDFNT WAS MOVG OUT OF THE SHENANDOAH VLLY AT 02Z. EFFECTS OF FNT HV BN A WND SHIFT AND LOWER DWPTS. NOT MUCH IN THE WAY OF COLD AIR UPSTRM. FCST MINS LUK GUD ACRS MOST OF THE AREA. WL RAISE FAR W TO NEAR 40 SINCE W99 WAS 52 DEGS AT 02Z. .LWX...SCA MD PTN OF CHES BAY AND TIDAL POTOMAC RVR. ARTHUR md AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1045 PM EST MON MAR 27 2000 00Z RAOBS AND SFC OBS/LATEST WV LOOP SHOWS OCCLUDED CYCLONE OVER ECNTRL LK SUP. SAT PIX INDICATE QUITE A BIT OF DRY AIR HAS WRAPPED INTO THE SYS...AND IR PIX SHOW LTL IN THE WAY OF ENHANCED CLD OVR CWA AND LK SUP WITH JUST A POORLY DVLPD CCB ON NW FLANK OF LO ACRS WRN LK SUP WHERE MODELS FCSTING SOME ISENTROPIC LIFT/MSTR ADVCTN AS DEPICTED ON 285-290K SFCS. CLD TEMPS WRMG MOST DRAMATICALLY OVR ERN CWA. LATEST PRES TENDENCIES SHOW SFC LO ARND 990MB JUST W OF CARIBOU ISLAND IN ERN LK SUP IS FILLING STEADILY... WITH 3HR PRES RISES GENERALLY 1-4MB OVR THE NORTHERN GRT LKS AS SHARP JET MAX AT H3 DIGGING SEWD TOWARD MID MS VALLEY AND TAKING BEST UPR DVGC WELL TO S. SFC LO APPEARS FARTHER W THAN MODELS...EVEN RECENT RUCS...HAVE BEEN FCSTG. STEADIEST SN OVR CWA HAS FALLEN OVR WRN ZNS...CMX RPRTS 6.7" TDAY AND PHOENIX IN KEWEENAW COUNTY 3.8". ALTHOUGH IWD HAS PICKED UP ONLY 2" SINCE THIS MRNG...THE MAJORITY OF THE SN HAS FALLEN SINCE LATE AFTN WITH AXIS OF LLVL CNVGC BTWN MORE NLY FLOW TO N AND NW FLOW TO S AS DEPICTED BEST BY LATEST RUC MODELS. LATEST 88D LOOP SHOWS REFLECTIVITIES INCRSG IN NCNTRL ZNS EVEN THOUGH LLVL FLOW REMAINS WLY AND LACKS UPSLOPE COMPONENT. MAIN FCST CONCERNS TNGT INCLUDE GOING HEADLINES OVR NW CWA FOR SN/ BLSN. SINCE SYS FILLING QUICKLY WITH UPR CNVGC/WEAKENING LLVL CNVGC/ CONTD PRES RISES FCSTD...XPCT ADDITIONAL SN AMTS TNGT TO BE RATHER MDT AND CONCENTRATED IN WEAK CCB COINCIDING WITH HIER RH DEPICTED ON 285-290K ISENTROPIC SFCS. THINK MODELS HAVE RIGHT IDEA IN FCSTG SFC LO TO START DROPPING S OVRNGT AS JET MAX IN MS VALLEY CAUSES LWRG PRES/UPR HGTS TO S. BUT SINCE SFC POSITION NOW A TAD FARTHER W THAN FCST...XPCT TRACK OF LO TO S FARTHER W THAN FCST. AVN/ETA WERE FCSTG SFC LO TO MOVE S TO NR GRAND MARAIS AT 06Z AND THEN TO NRN LWR MI BY 12Z. QUICK PEEK AT 00Z ETA SHOWS SIMILAR TREND MOVG SYS TO NR GARDEN PENINSULA BY 06Z...SEEMS A BIT TOO FAST GIVEN RECENT TRENDS. XPCT SFC LO NR MUNISING AT 06Z. WHAT THIS MEANS IS THAT ERN EDGE OF CCB WL NOT REACH MUCH FARTHER E THAN MUNISING TO RAPID RIVER. AS UPR DYNAMICS CONT TO WEAKEN...UPSLOPE ENHANCEMENT WL BCM MORE CRITICAL IN MAINTAINING HEAVIER SN. NLY FLOW FAVORS WAKEFIELD-ROCKLAND AND HERMAN-NEGAUNEE. SINCE KEWEENAW ZNS NOT FVRD WITH THIS FLOW...HAVE DOWNGRADED WSW TO SN/BLSN ADVY THERE. WITH 2 G/KG AVBL AT H7-75... XPCT NO MORE THAN 3 INCHES ADDITIONAL ACCUM REST OF NGT WITH THE HEAVIER AMT OVR FVRD HIER TERRAIN. SHARP PRES GRADIENT FCST TO REMAINS OVR WCNTRL ZNS OVRNGT WITH NEW ETA BNDRY LYR WNDS SUGING 20 TO 30 MPH IN EXPOSED AREAS WITH GUSTS UP TO 40 MPH. THESE STRG WNDS WL CAUSE BLSN...ESPECIALLY IN OPEN AREAS. BUMPED UP MIN TEMPS A BIT IN CNTRL ZNS BASED ON XPCTD TRAJECTORIES AND UPSTREAM DWPTS IN UPR 20S TO MID 30S. .MQT...SN/BLSN ADVY TNGT MIZ002-009 SN/BLSN ADVY INTO TUE MRNG MIZ001-003-004-005. KC mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1035 PM EST MON MAR 27 2000 LATEST KGRR-88D AND SURROUNDING SITES SHOW A SLIGHT DIMINISHING TREND IN THE INSTABILITY CONVECTION ACROSS THE SRN GREAT LAKES THIS EVENING. IR SATL IMAGERY SHOWS ONE AREA OF CONVECTIVE PCPN OVR EXTREME SRN WI...NRN IL...SRN LAKE MI...AND ACROSS SRN LOWER MI. SOME CLEARING NOTED IN SUBSIDENCE AREA BEHIND THE VORT ENERGY RESPONSIBLE AND BEYOND THAT...WIDESPREAD LOW CLOUDS AND SCT SNOW SHOWERS OVER NRN WI AND WRN UPPER MI ASSOCIATED WITH NEXT PIECE OF ENERGY ROTATING AROUND UPPER LEVEL LOW. LATEST AVAILABLE RUC II AND 00Z ETA MODELS SHOW THE FIRST BATCH OF PCPN MAINLY E OF THE FORECAST AREA BY 09Z WITH A BREAK IN THE ACTIVITY UNTIL AFT 12Z WHEN NEXT DISTURBANCE COMES INTO PLAY. THEREFORE...DECIDED TO DECREASE POP IN THE EVENING UPDATE TO 40PCT/SCT CATEGORY FOR OVERNIGHT PERIOD. WITH COLDER AIR WORKING IN BEHIND TROUGH PASSAGE AND A COOLING SFC LAYER...MIXED PCPN STILL POSSIBLE LATER TONIGHT. TEMPERATURES ARE A CONCERN FOR OVERNIGHT. IF SOME PARTIAL CLEARING WORKS IN...READINGS COULD FALL BELOW FORECAST VALUES EASILY. HOWEVER...LOOKING UPSTREAM IN WI...STRONGER SFC WINDS NOTED IN CLEAR AREAS AND TROUGH PASSAGE SHOULD INCREASE WIND SPEEDS SOMEWHAT OVER THE FORECAST AREA LATER THIS EVENING. .GRR...NONE. GREENE mi AREA FORECAST DISCUSSION 945 AM CST MON MAR 27 2000 FORECAST PROBLEM FOR THE AFTERNOON IS EXTENT OF PRECIP AND INCREASING WIND. BASED ON RADAR COMPOSITE..LOOKS LIKE BETTER CHANCE OF RAIN/SNW SHOWERS MOVING DOWN A LITTLE FARTHER WEST. WILL INCREASE POPS OVER A FEW OF THE WST CENTRAL ZONES. 12Z RUC AND ETA SHOWING MAX LOW LEVEL COLD ADVECTION SLIDING INTO SOUTHWEST MINNESOTA AND STRONGEST 850 MB WINDS ALSO FORECAST IN THIS AREA FOR LATER THIS AFTERNOON. AREAS OF SOUTH CENTRAL MN WILL SEE A LITTLE MORE HEATING THIS MORNING WHICH WILL INCREASE THE LAPSE RATE. WILL GO AHEAD AND EXPAND THE WIND ADVISORY INTO SOUTH CENTRAL MN. LOW LEVEL THICKNESS INITIALLY A LITTLE ON THE WARM SIDE OVER PARTS OF THE SOUTH SO WILL KEEP THE MIX GOING. AREAS NORTH OF STC UP TO AXN PROBABLY ALL SNOW. MAY BE SOME FALLING TEMPS NORTH AND THEN NEARLY STEADY A FEW OTHER AREAS. .MSP...WIND ADVISORY THIS AFTEERNOON SW OF KAXN...KHCD...KMKT..KAEL JPR mn FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 825 PM CST MON MAR 27 2000 ...CLEARING TRENDS/TEMPS/WINDS EVENING FORECAST CONCERNS... WEAK HI PRES (1014MB) CENTERED NR LK WINNIPEG THIS EVE...WITH STIFF GRAD CONTINUING ESP RRV AND E. LGT WINDS DVLPNG ARND DVL BASIN AND POINTS W. LO PRES IN GRT LKES NOT MOVING MUCH AS IT ENCOUNTERS BLOCKING TO THE E. H85 MOISTURE FIELD CONTINUES TO SPIRAL AROUND LO...WITH EVEN A BRF WWD EXPANSION DURING THE ERY EVE AS SUM CLOUDS BACKED INTO KDVL. HOWEVER...LATE MSAS PICS CONFIRM PRES RISES NOW PICKING UP TO E/SE OF YWG AND THIS SHUD ALLOW HI PRES TO NOSE DOWN AND PUT THE CLAMPS ON WWD PUSH OF CLOUD. EVE IR PIC ALSO INDICATING IMPRESSIVE CLEARING EDGE SINKING S THRU RRV WITH EVEN A FEW HOLES APPEARING IN MN CWA. LEFTOVER -SHSN/FLURRIES ERY THIS EVE ALL JUST A FADED MEMORY NOW. GUSTINESS CONTINUES ESP IN SRN RRV AND E/SE ZONES. LGT WINDS JUST UPSTREAM AND DARKNESS SHUD CURTAIL GUSTS BUT STILL ARND 10KT WIND AT YWG NOT ALLOWING RAPID TEMP DROP YET. EVENTUALLY LGT WIND SHUD ALLOW FOR BETTER RADIATIONAL COOLING CONDITIONS AFTR 06Z. UPSTERAM TD/S COOL...BUT NOT OVERLY IMPRESSIVE. LATEST RUC/ETA APPEARS ON TARGET WITH CURRENT TEMP REGIME...AND LOWERS N/NW ZONES TO 15 BY 12Z WITH WARMER NUMBERS E/SE WHERE CLOUDS SHUD LINGER. FEEL 10-15F MAY BE BIT TOO AGRESSIVE IN DVL/GFK AREA AND WL UP SLIGHTLY...AS PER LATE OBS AND RUC/ETA/LAMP MODEL DATA. 00Z ETA ALSO DEPICTS CURRENT MOISTURE FIELD NICELY AND IS QUITE AGRESSIVE WITH CLEARING ALL OF CWA BY LATE TNGT...THUS WL CONTINUE TREND OF CLEARING IN EVEN FAR SE ZONES AFTR MDNGT. FEW OTHER MINOR TEMP TWEAKS UPWARD MAY ALSO BE NECESSARY...ESP NRN ZONES. ANY OTHER CHANGES TO BE COSMETIC WORDING TO CLEAN UP ERY EVE MENTIONS. .FGF...NONE. SOROKA nd FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 955 AM CST MON MAR 27 2000 FORECAST CHALLENGE FOR UPDATE CONCERNS WIND...SNOW EXTENT AND TEMPS. STRONG CYCLONIC FLOW PROVIDING PLENTY OF CHALLENGES FOR FA TODAY. KMVX-88D INDICATING NARROW BAND OF ENHNACED SNOWFALL DROPPING SOUTH THROUGH FA ASSOCIATED WITH SFC COLD FRONT AND VORT CENTER QUITE EVIDENT FROM WV LOOP. VSBY BRIEFLY DROPPED TO 1/2 MILE AT GFK HOWEVER ACCUMULATION BEEN ONLY A DUSTING AT BEST. AS VORT DROPS SOUTH NVA TO FOLLOW AS VISIBLE IMAGERY SHOWING BREAKS UPSTREAM WITH CLD COVER MORE CUMULIFORM IN NATURE. HOWEVER LATEST RUC INDICATING MOIST LAYER BETWEEN H8-9 AND WITH H8 COLD POOL DROPPING OVR FA ANY BREAKS LIKELY TO FILL WITH -SHRASN POSSIBLE. VIS LOOP ALSO INDICATING SOME ENHANCED CU UPSTREAM SO INSPITE OF NVA WILL CONTINUE WITH RASN SHOWERS BEHIND MAIN BAND ALTHOUGH SHOULD BE MORE SPOTTY. STRONGEST CAA OVR NORTHERN FA ATTM AND WILL SPREAD SOUTH DURING DAY. TEMPS DROPPING SIGNIFICANTLY WITH THIS FEATURE AND WITH CLOUD COVER RECOVERY WILL BE SLIGHT. WILL NEED TO DROP MAX TEMPS ACROSS THE NORTH TODAY AND WILL LIKELY HOLD TEMPS FAIRLY STEADY ACROSS THE SOUTH. TIGHT GRADIENT ALONG WITH SIG PRESSURE RISES DROPPING SOUTH FROM MSAS. H85 12Z UA ANALYSIS NOT SHOWING REAL STRONG WINDS AT H8. HOWEVER KMVX VWP SHOWING A STEADY 30-35KT UP TO 10K. WITH LATEST RUC SOUNDING SHOWING ADIABATIC LAPSE RATES TO H85 AND WITH CAA SHOULD MIX DOWN. WILL CONTINUE WIND ADVISORY. .FGF...WIND ADVISORY TODAY FOR ALL OF ERN ND AND THAT PART OF NW MN ALONG AND WEST OF A ROX-DTL-FFM LINE. VOELKER nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 850 PM EST MON MAR 27 2000 DISC: FLASH FLOOD EVENTS HISTORICALLY OCCUR IN THE MIDDLE OF THE NIGHT AND WE SEE THE POTENTIAL UNFOLDING AGAIN...IF ALL INGREDIENTS COME TOGETHER. PRIMARY CONCERN IS AREA THAT RECIEVED 4 TO 5 INCHES ON THE 22ND IN SE PA TO LESS THAN A TENTH OF AN INCH IN N CENTRAL NJ. SO AS MARFC HAS INDICATED...FOCUS W/B IN THE SE SECTIONS OF PA AND WE ALSO HAVE TO LOOK AT NRN DE. HEAVIEST RAIN WILL ACCOMPANY LO EXPECTED TO FORM OVER THE CHESAPEAKE BAY OVERNIGHT AND MOVE NE. RUC2 AND MESO ETA CONTINUING TREND OF EARLIER MODELS OF BRINGING MAX PCPN OVERNIGHT WITH AMNTS OF 1 TO 2 INCHES. LOCAL EXCESSIVE CHKLIST GIVEN PWT'S SUGGEST ISOLD MAX AMOUNTS OF 2.2-2.4 INCHES UNDER "IDEAL". HOWEVER NEGATING THAT ARE THE WINDS WHICH ARE VERY STRONG THROUGH OUT THE LAYER WHICH IS NOT CONDUCIVE TO A FAVORABLE HODO. THCKNESS VALUES MOST FAVORABLE E OF PHL GIVEN THE TIME OF YEAR. HOWEVER...WE ARE IN FOR A PERIOD OF STRONG OVERRUNING INTO EARLY MORNING HOURS IN THE SOUTHEAST AND EXTEND FARTHER NORTH AFTER 12Z. EVERY ONCE IN A WHILE THERE IS SOME POS LIGHTNING HITS IN ERN PA BUT THE MOST IMPRESSIVE IS OFF THE NC COAST. AS THE LOW DEEPENS WINDS WILL INCREASE FROM THE S-SE AND ADVECT ATLC RICH MOIST INTO REGION AND THERE WILL BE SOME ISOLATED CONVECTION. RUC2 IS SHOWING A MAX OF 1 INCH BY 06Z AND THE ETA CLOSE TO AN INCH IN SAME GENERAL AREA. WINDS ACROSS THE TENN VALLEY 100KT AT 50H WILL CAUSE SYSTEM TO BECOME NEG TILTED. WV SHOWS STRONG PUSH INTERN NRN GULF COAST STATES. HARKENS BACK TO JAN 25 WHEN SYSTEM TRACKED FARTHER W. NOT GOING TO CHANGE EXISTING FFS OR FCST ON THE MARINE. BUOY WINDS UPSTREAM GUST 4O KT. HIGH TIDE ON THE NJ AND DE COAST OCCURS IN THE EARLY MORNING HOURS 1-2 AM. TIDES ARE LO BUT THERE MAY BE SOME ISOLATED PONDING ON THE ROADS ONCE WE GET INTO THE HEAVIER RAIN AND INCOMING TIDE SRN DE/SRN NJ BUT PROB GO UNNOTICED WITH LO VOLUME ON THE ROADS. NEXT HIGH TIDE OCCURS IN THE AFTERNOON WITH NO PROBLEMS. SO...SEE YA. .PHI...FLASH FLOOD WATCH OVERNIGHT PA054-055-060>062-067>071-NJZ001 -007>010-012-016>019-DEZ001-MDZ008-012-281600- SMALL CRAFT ADVISORIES FROM SANDY HOOK NJ TO FENWICK IS DE AND 20 NM OFFSHORE AND DELAWARE BAY. EBERWINE pa AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX 950 PM CST MON MAR 27 2000 28/03Z SFC ANALYSIS INDICATES LIGHT SELY FLOW PREVAILING E OF MOUNTAINS WITH DRY AIRMASS NOTED BY DEWPOINTS IN THE MID 20S-30S. AM CONCERNED ABOUT LOW CLOUDS ADVECTING/FORMING NWWD LATER TNGT ACROSS EDWARDS PLATEAU/ERN PERMIAN BASIN. NEW ETA/RUC GUIDANCE PROGS SHALLOW LOW LEVEL MOISTURE ACROSS ERN CWA TOWARD DAYBREAK. PREVIOUS FORECAST DISCUSSION MENTIONED THIS POSSIBILITY. UPDATED ZFP ISSUED WITH RECONFIGURED ZONE GROUPINGS ALLOWING FOR LOW CLOUDS LATE TONIGHT/ EARLY TUESDAY ERN SECTIONS. APPEARS SHALLOW MOISTURE DOES NOT LINGER LONG TUESDAY PER NEW MODEL DATA. WITH SCENARIO OF DRY SWLY LOW LEVEL FLOW DID ADJUST TEMPS UPWARD ONE CATEGORY TUE SOME AREAS FROM PREVIOUS FORECAST. BF .MAF... TX...NONE. NM...NONE. tx DEEP SOUTH TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE BROWNSVILLE TX 925 AM CST MON MAR 27 2000 SHORT TERM...SURFACE OBS FROM ACROSS THE STATE INDICATE THAT THE COLD FRONT HAS PENETRATED INTO SOUTH CENTRAL TEXAS GENERATING ONLY A WIND SHIFT AND MODERATE CLD COVER. MESO-ETA AND RUC GUIDANCE BRING A GRADUALLY WIND SHIFT TO THE WEST TO NORTHWEST ACROSS THE CWA WITH NORTHERLY WINDS PREVAILING AROUND 18Z. EARLY MORNING FOG HAS DISSIPATED OVER DEEP SOUTH TEXAS LEAVING ONLY A PATCHY AND THIN ST DECK OVER THE REGION. AFTERNOON HEATING WILL STEADILY ERODE THIS LEAVING BEHIND PARTLY TO MOSTLY SUNNY CONDITIONS. THE WIND SHIFT WILL LIKELY DO LITTLE TO DROP TEMPS ANY TODAY WITH 80S AND 90S PREVAILING. MARINE...SURFACE WINDS SHIFTING TO THE NORTHEAST TO EAST FROM THE ABOVE MENTIONED FRONTAL BOUNDARY ARE NOT STRONG ENOUGH TO GENERATE ROUGH BAY AND GULF CONDITIONS TODAY. SO WILL MAINTAIN CURRENT CWF WORDING. SYNOPTIC/MESO...60/INTERN...CASTILLO INTERNET ADDRESS...WWW.SRH.NOAA.GOV/BRO .BRO...NONE. tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DODGE CITY KS 300 AM CST TUE MAR 28 2000 MAIN CHALLENGES TO THIS FORECAST PACKAGE WILL BE TIMING OF PRECIPITATION AND TEMPERATURES. 07Z SURFACE MAP SHOWED COOL FRONT HAD BACK-DOORED THROUGH MOST OF CWA, EXCEPT FOR EXTREME SOUTH AND SOUTHWEST EDGES. RUC 06Z MODEL SEEMED TO PICK UP ON THIS FRONT/S TIMING FAIRLY WELL, WITH ETA NEXT BEST. 28/00Z MODEL INITIALIZATION ALSO SHOWED ETA BEST WITH 5OOMB LEVEL PRESSURE FIELDS. 850MB MODEL COMPARISON SHOWED AVN AND ETA IDENTIFIED +16C WARM RIDGE THROUGH COLORADO AND NORTH INTO WYOMING THE BEST. WITH TIME, ALL MODELS SET UP AN OVER-RUNNING EVENT, WITH A NEARLY STATIONARY FRONT ORIENTED WEST TO EAST ACROSS NORTHERN OKLAHOMA BY THIS EVENING. SOUTHERLY MOIST FLOW BECOMES ESTABLISHED BY ABOUT 02Z, WITH ISENTROPIC LIFT MOVING SATURATED LAYER NORTH AND THEN EAST INTO WESTERN KANSAS BY 06Z. WILL FOLLOW LEAD OF ETA MODEL BRINGING LOW LEVEL JET FIRST NORTH ON EAST SLOPES OF ROCKIES THIS EVENING, THEN TILTING NORTHEAST INTO WESTERN PART OF CWA. THIS WILL LEAD TO A WIDESPREAD RAIN EVENT ACROSS MOST OF CWA BY WEDNESDAY. IN THE MEAN TIME, WILL GO WITH HIGHEST POPS (60) IN EXTREME SOUTHWEST CORNER TONIGHT, BUT FALL OFF TO 30 PERCENT IN DDC/GCK AND 20 PERCENT LATE FOR LIGHT RAIN IN NORTHEAST CWA. MINOR RIPPLE IN UPPER FLOW COMES INTO PLAY AROUND 29/12Z AND WILL GO WITH 70 POPS MOST LOCALS ON WEDNESDAY FOR RAIN. AMOUNTS ARE HARD TO NAIL DOWN AT THIS TIME, AND HOW FAR NORTH ISENTROPIC BOUNDARY IS DURING DAY WEDNESDAY WILL BE DETERMINING FACTOR OF HOW LONG RAIN CONTINUES AND WHERE MOST WILL FALL. WILL MENTION POSSIBLE THUNDER IN SOUTHWEST GROUP, BUT NOT PLAY UP TOO MUCH DUE TO THE RELATIVELY WEAKNESS OF WAVE COMING ACROSS. FOR TEMPS, WILL LEAN TOWARD FAN GUIDANCE. THINK FWC IS MUCH TOO COLD FOR TONIGHT/S LOWS, AND WOULD HAVE TO INTRO SOME FROZEN/FREEZING PRECIP IF FWC WAS FOLLOWED. EXTENDED DISCUSSION... GOING EXTENDED FORECAST LOOKS ON TRACK FOR THE MOST PART. WILL TAKE WEDNESDAY NIGHT/S LOW TEMPS JUST A FEW DEGREES LOWER, TO BETTER MATCH CHANGES IN WED HIGH TEMPS. NO OTHER CHANGES AT THIS TIME. PRELIMINARY GUIDANCE FOR COORDINATION ONLY. OFFICIAL FORECASTS ARE CONTAINED WITHIN THE DODGE CITY ZONE FORECAST. DDC 055/038 050/039 053 027 GCK 056/037 050/038 052 037 EHA 056/039 049/039 053 067 LBL 057/038 050/040 054 057 HYS 053/035 047/038 046 025 P28 059/039 052/042 055 037 .DDC...NONE. BURKE/MCCAMMON ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DULUTH MN 230 AM CST TUE MAR 28 2000 FOCUS TODAY WILL BE ON CLD TRENDS AND TEMPS. UPR LOW AND SFC LOW STACKED OVER ERN LK SUPR IS MOVG SE AS UPR RDG EDGES INTO WRN DAKS. VORT SPOKES ROTATING ARND THE LOW HAVE PRODUCED SNW SHWRS IN NWRN WI. TWO TO FOUR INCHES WAS REPORTED AND 88D SUGGESTS IT'S MAINLY A TERRAIN INFLUENCE. BUT NVA IN THAT AREA FOLLOWING ONE SPOKE IS DECREASING SNOW SHWR ACTIVITY ON DLH 88D. THE 11-3.9 CHANNEL SHOWS MORE S/C OVR ERN ONT HEADED FOR THE ARROWHEAD BEFORE THINNING AGAIN TODAY WITH THE ARRIVAL OF THE SFC RIDGE. RUC AND ETA HAVE A GOOD DEPTICTION OF THESE FEATURES AND THE ETA WILL BE THE MODEL OF CHOICE TODAY. CROSS SECTIONS SHOWING A RATHER JUICY LOWER LYR WITH SGFNT DRY AIR ALOFT. SUBSIDENCE INVERSION STRENGTHENS TODAY. MIXING IN MN WILL PRODUCE PC BY AFTN AS RIDGE MOVES OVER. WI AND ERN MN SHOULD SEE A MIX OF CLDS AND SUN WITH SOME SNW SHWRS IN WI DUE TO A FEW MORE SPOKES OF PVA ON THE WEST SIDE OF THE UPR LOW. TEMP GDNC APPEARS A COUPLE OF DEG TOO WARM BASED ON NGM PERFORMANCE YDA AND THE EXPECTED PERSISTENCE OF S/C OVR THE AREA TODAY. IT DOESN'T TAKE MUCH WITH A PERIOD OF MARCH SUN TO WARM THINGS UP, THOUGH. THE LOW 50S FOR WED WILL BE TRIMMED A BIT IN MN AND KEEP THE MAINLY MID TO 40S FOR WI ZONES WITH UPPER 40S ON THE WRN BORDER CLOSER TO THE SUNSHINE. .DLH...NONE. $$ CS mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON SC 1016 AM EST TUE MAR 28 2000 LTST SAT PICS SHO CLR SKIES ACRS RGN ATTM. SOME MID CLDS ALONG AND NW OF APPALACHAINS ASSCD WI APPCHG CDFNT. PLNTY OF DRY AIR IN PLACE AND WI VORTS REMNG WELL N OF THE RGN...CLDS WL DSPT AS THEY APPRCH CWA. THEREFORE WL CONT SNNY FCST. ? FOR TDY IS HOW STG WINDS WL GET. CAN COUNT ON ONE HAND TIMES WE HAVE HAD SUSTAINED WINDS OVR 25 KT (MINUS HURRICANES) IN JST PAST FEW YEARS...SO WL NOT GO OVRBOARD ON THIS JST YET. HWVR...RUC/MESOETA/ETA/NGM/AVN ALL CONSITENT IN DRIVING H8 45-50 KT JET ACROSS RGN LTR THS AFTN....WI 45 KT EVEN SHOWING UP AT H925 AND H950 ON RUC/MESOETA. WI FULL SUN AND APPCHNG CDFNT...SHUD HV NO PROBLM MIXING DOWN MAJORITY OF THS WIND. FOR NOW WL GO WI BECOMING WINDY EVERYWHERE...THO WL WTCH CLOSELY IN CASE ADVISORY NEEDED. TEMPS MOSTLY ON TRACK AND WL ONLY TWEAK UPWARD A LTL FOR SE GA. NO OTR CHANGES PLANNED. CWF...CURRENT OBSERVATIONS SHOWING A LULL FROM THE STRONGER OVERNIGHT WINDS ASSOCIATED WITH THE NOCTURNAL JET. HOWEVER...WINDS STILL EXPECTED TO INCREASE DURING THE AFTERNOON AS THE GRADIENT TIGHTENS. DO NOT ANTICIPATE ANY SIGNIFICANT CHANGES IN MORNING UPDATE. .CHS... SC...SMALL CRAFT ADVISORY S SANTEE RIVER SC TO SAVANNAH GA OUT 20 NM. LAKE WIND ADVISORY FOR AREA LAKES THIS AFTERNOON. GA...SMALL CRAFT ADVISORY SAVANNAH TO ALTAMAHA SOUND GA OUT 60 NM. LAKE WIND ADVISORY FOR AREA LAKES THIS AFTERNOON. WOODWORTH/JH sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 1019 AM EST TUE MAR 28 2000 COLD FRONT ON PLATEAU. MOST OF THE SHOWERS HAVE MOVED OUT OF THE CWA. MESOETA AND RUC PROG THE FRONT THROUGH OUR AREA BY 18Z...BUT SATELLITE SHOWING ANOTHER SHORTWAVE OVER OH VALLEY. CLOUDS HAVE SCATTERED ACROSS THE VALLEY...WILL USE VARIABLE CLOUDINESS FOR THE CENTRAL AND NORTHERN VALLEY AND LOWER POPS A LITTLE SINCE PRECIP LOOKS FARTHER NORTH WITH THIS NEXT BATCH. STRONG WINDS WILL CONTINUE THIS AFTERNOON. WINDS GUSTING TO 30 ACROSS THE VALLEY. 850 WINDS PROGGED TO BE 40 KNOTS...BUT NO REPORTS OF TREES DOWN IN THE MOUNTAINS. WON'T ISSUE AN ADVISORY. TEMPERATURES SOARING OVER THE SOUTHERN VALLEY. WILL BUMP UP TEMPERATURES IN THE SOUTHERN ZONES. .MRX... NC...NONE. TN...NONE. VA...NONE. GH tn DEEP SOUTH TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE BROWNSVILLE TX 900 AM CST TUE MAR 28 2000 CURRENT RUC SFC WINDS SHOW OFFSHORE WILL MAINTAIN 15 KTS FM THE SE THRU 21Z...INCREASING TO 15 TO 20 KT BY 00Z. WL RAISE LAGUNA AND OFFSHORE TO 15 TO 20 KT AND GUSTY WITH "SCEC". SFC TROF EDGES TO BIG BEND BY 00Z...WITH TIGHT PGF OVR DEEP S TX. MEAN RH DECREASES DURING THE PM...ACCORDING TO RUC...AND XPCT SCT CONDITIONS BY AFTERNOON. RUC TIME/HEIGHT HAS MID LVL MSTR GONE BY NOON...AS VLY CURRENTLY HAS BKN DECK AT 18K FT ADVECTING E QUICKLY. TEMPS SHUD BE A CAT LWR THAN MON'S MID 90S...WITH LOWER 90S CONFINED TO WRN HIDALGO AND POINTS WEST...WITH BRO AND HRL 86-87 DEG F. WL MV TEMPS SLIGHTLY DOWN AND BETTER DEFINE FCST HIGHS. SYN...PHILO 58/MET INTERN...CASTILLO .BRO...SCEC ALL MARINE ZNS. tx NORTHERN ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FLAGSTAFF AZ 300 PM TUE MAR 28 2000 SYNOPSIS...RAIN AND HIGH ELEVATION SNOW SHOWERS...ALONG WITH ISOLATED THUNDERSTORMS...WILL CONTINUE THROUGH THIS EVENING WITH SHOWER ACTIVITY DECREASING OVERNIGHT. SEVERAL WEAK DISTURBANCES WILL MOVE ACROSS THE STATE OVER THE NEXT FEW DAYS AND WILL BRING A CHANCE FOR SHOWERS EACH DAY. HIGH PRESSURE WILL BEGIN A DRYING AND WARMING TREND BY THE WEEKEND. DISCUSSION...LOW PRESSURE SYSTEM ALOFT HAS MOVED INTO CENTRAL NM DURING THE DAY. DEEP MOISTURE AND LOW CLOUDS COVERS MUCH OF THE STATE THIS AFTERNOON WITH AREAS OF LIGHT RAIN AND MOUNTAIN SNOW SHOWERS...AND A FEW THUNDERSTORMS...CONTINUING. FLOW ALOFT HAS BECOME WEAK ON THE NORTH SIDE OF THE NM CIRCULATION WITH A WELL-DEFINED DEFORMATION ZONE PRESENT OVER CWFA. NEXT WAVE UPSTREAM IS ALREADY MOVING INTO THE CWFA THIS AFTERNOON WITH AN INCREASE IN WINDS ALOFT AND STEEPENING THE LAPSE RATES SLIGHTLY. LI'S ARE IN THE -2 TO -4 RANGE THIS AFTERNOON AND WILL REMAIN UNSTABLE INTO THE EARLY EVENING HOURS. THUS...EXPECT SHOWERS AND THUNDERSTORMS TO PERSIST FOR AT LEAST A FEW HOURS INTO THE 1ST PERIOD. RUC AND ETA SIMILAR IN THIS FEATURE AND INDICATE THAT PRECIP ACTIVITY WILL DIMINISH THIS EVENING FROM WEST TO EAST...BUT PROBABLY NOT END COMPLETELY...ESPECIALLY IN THE NE ZONES. ETA AND AVN CONTINUE TO EXHIBIT BROAD CYCLONIC TROUGH DEVELOPING OVER THE SOUTHWEST THROUGH 4TH PERIOD. THIS WILL LIKELY KEEP TEMPS NEAR OR BELOW SEASONAL NORMALS AND MAINTAIN A CHANCE OF SHOWERS EACH DAY. EXTENDED...ECMWF...MRF...AND CDN MODELS VERY SIMILAR IN ALLOWING CLOSED LOW TO SAG TO THE SOUTHWEST DURING THE EXTENDED PERIOD. DIFFERENCES ARISE AS TO HOW FAR TO THE SOUTHWEST IT WILL GO...WHEN IT WILL EJECT...AND TRAJECTORY OF SYSTEM WHEN/IF IT EJECTS. FOR NOW WILL GO WITH UNSETTLED WEATHER ON DAY 3 AND DECREASE CLOUDS WITH WARMING TEMPERATURES ON DAYS 4 AND 5. DB. .FGZ...NONE. az SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO 103 PM MST TUE MAR 28 2000 ...FORECAST CHALLENGE WILL BE TIMING AND AMOUNT OF PRECIPITATION TONIGHT ACROSS FORECAST AREA... CURRENTLY ACROSS THE REGION A BROAD TROUGH OF LOW PRES LAY ACROSS THE GREAT BASIN...WHILE AT THE SFC LOW PRES WAS LOCATED ACROSS NE NEX MEXICO/SE COLORADO. ABUNDANT CLOUD COVER WAS FOUND ACROSS THE CWA...ESPECIALLY OVER THE SAN LUIS VALLEY AND WESTWARD AS PER VISIBLE SATELLITE IMAGERY AND SFC OBS. ALSO...A FEW LTG STRIKES ARE BEING PICKED UP BY AWIPS OVER N NEW MEXICO. SPOTTER REPORTS THIS AFTN INDICATE VERY LIGHT SNOW AT WOLF CREEK AND MONARCH SKI AREAS. TEMPS ACROSS THE SAN LUIS VALLEY AND E PLAINS HAVE BEEN GENERALLY IN THE 50S TO NEAR 60. TONIGHT AND WEDNESDAY...A PAIR OF UPPER LEVEL DISTURBANCES...ONE NORTH AND ONE SOUTH OF CO...MOVING THROUGH THE FLOW WILL CONTINUE THICKENING CLOUDS AND PCPN CHANCES ACROSS THE CWA TONIGHT THROUGH WED MORNING. HOWEVER...500 MB VORT CHARTS SHOW THAT THESE SHORTWAVES TEND TO WEAKEN AND BREAK APART AS THEY MOVE ACROSS THE AREA. OTHER THAN THE SHORTWAVES...THE MOISTURE ENTERING THE AREA HAS VERY LITTLE TO WORK WITH TO BRING ABOUT ANY SIGNIFICANT PCPN. LATEST RUC ANALYSIS INDICATES PCPN WEST OF THE CONT DIVIDE THROUGH WED 06Z...WITH VERY LITTLE TO NIL EAST OF THE MTNS. I STILL BELIEVE THAT SHOWERS WILL DEVELOP IN THE EAST...BUT WILL RETHINK THE STRENGTH OF THE SHOWERS...AND WILL STALL DEVELOPMENT EVEN FURTHUR. THEREFORE WILL DROP LIKELYS IN THE EAST AND GO WITH 30-40% POPS...AND HAVE PCPN EAST OF THE MTS START OVERNIGHT...MOST LIKELY AFTER MIDNIGHT. ETA DIVQ CHARTS INDICATE UPWARD MOTION ACROSS CWA THROUGH WED 12Z...THEN DOWNWARD MOTION MOVING IN AROUND 18Z. THIS LEADS ME TO THINK THAT ANY SHOWERS OCCURRING TOMORROW MORNING WILL BEGIN TO TAPER OFF BY AROUND NOON...LATER FARTHUR OUT EAST...AND REGION WILL PROBABLY SEE SOME CLEARING OF THE CLOUDS FOR THE LATE AFTERNOON INTO THE EVENING. ONE NOTE...PREVIOUS FORECAST THINKING WAS THAT THERE WAS A CHANCE FOR POSSIBLE MARGINAL SEVERE STORMS FOR THE FAR E PLAINS WED AFTN...DUE TO FAVORABLE SHEAR AND CAPES. SOMEWHAT SKEPTICAL AT THIS TIME...BUT WITH INCREASED INSOLATION DUE TO CLEARING SKIES WED AFTN...CONVECTION IS NOT OUT OF THE QUESTION. WILL KEEP MENTION OF A FEW POSSIBLE THUNDERSTORMS WED AFTN FOR THE FAR E PLAINS. AS FOR TEMPS...LITTLE CHANGE AT 700 AND 850 MB. CLOUD COVER TONIGHT WILL HELP TEMPS MODERATE...WHILE HIGH READINGS WED WILL BE COMPARABLE TO TODAYS HIGHS. WEDNESDAY NIGHT AND THURSDAY...THE LOW TROUGH OVER THE GREAT BASIN GETS MORE DEFINED WED NIGHT...AND BY EARLY THURS MORNING A LOW CLOSES OFF OVER UTAH AND STARTS TO DROP S-SW. ETA CROSS-SECTIONS INDICATE THAT BY THURS AFTN AND EVE DEEP MOISTURE SETS UP ACROSS THE ENTIRE CWA...WITH A STRONG E-NE UPSLOPE FLOW. THURSDAY SHOULD START OFF RELATIVELY MILD AND PARTLY CLOUDY...BUT CONDITIONS WILL DEVELOP RAPIDLY AND BY THE AFTERNOON CLOUDS SHOULD BE MOSTLY CLOUDY TO OVERCAST. THURS NIGHT...CONDITIONS WILL BE VERY FAVORABLE FOR PCPN REGIONWIDE. EXTENDED...(FRI-SUN)...THE LOW PRES SYSTEM OVER UTAH ON THURS IS PROGGED TO DROP TO THE SW ACROSS SOUTHERN CA...PROVIDING ANOTHER CHANCE FOR PCPN ON FRI. SAT AND SUN IT CONTINUES SW AND STRENGTHENS...SETTING UP OFF THE CA BAJA...AND DROPPING FAR ENOUGH S FOR A COUPLE OF DAYS OF DRY WEATHER FOR THE REGION. .PUB...NONE. MOORE co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 400 PM EST TUE MAR 28 2000 BROAD CYCLONIC FLOW AT LOW LEVELS CONTINUES ACROSS THE WESTERN GREAT LAKES REGION. Q-G FORCING REMAINS MINIMAL... HOWEVER WEAK LOW LEVEL CONVERGENCE ALONG WITH THE DAYTIME HEATING (SFC-500 MB INSTABILITY)...SHOWER ACTIVITY HAS BEEN ABLE TO BECOME A LITTLE MORE WIDESPREAD THIS AFTERNOON AS PER MOSAIC RADAR LOOPS. IN ADDITION...WITH FREEZING LEVELS AROUND 3000-3500 FEET MSL ALONG WITH THE HIGH DEGREE OF SFC-500 MB INSTABILITY (500 MB TEMPS AROUND -32C AND TOTAL-TOTALS IN THE MID/UPPER 50S)...DEEPER CONVECTION HAS RESULTED IN AREAS OF SLEET/SMALL HAIL. MODIFIED RUC/LAPS SOUNDINGS IN FACT SHOW CONVECTIVE EQUILIBRIUM LEVELS JUST ABOVE 500 MB... CORRELATING WELL WITH THE CONVECTIVE CLOUD TOPS PER THE LATEST IR LOOPS (WITH TEMPS AROUND -35C). INITIAL FORECAST CONCERN WILL BE WITH DIURNALLY-DRIVEN SHOWER ACTIVITY (ALONG WITH PRECIP TYPE)...NEXT CONCERN WILL BE WITH PRECIP CHANCES ON THE EAST SIDE OF THE STATE AS WEAK VORT LOBE ROTATES AROUND BACK SIDE OF UPPER LOW. SHORT TERM DISCUSSION...WILL CONTINUE WITH SCATTERED SHOWER WORDING THIS EVENING IN MOST ZONES (BOTH RAIN AND SNOW MENTION)... PARTICULARLY OVER THE SRN AND SW PORTIONS OF NRN LWR WHERE THE ECHOES ARE MOST PREVALENT. DIMINISHING DIURNAL INSOLATION (LOWERING SFC LAYER TEMPS) WOULD INCREASE THE LIKELIHOOD OF MORE SNOW THAN RAIN...THOUGH AT THE SAME TIME WILL DIMINISH THE ACTIVITY AS WELL. AFTERWARDS...WILL INCLUDE HIGHER POPS ACROSS ERN PORTIONS OF UPPER MI AND NRN LWR GIVEN THE INCREASED Q-G FORCING (PDVA AND 850-500 MB Q-VECTOR CONVERGENCE) IN RESPONSE TO THE VORT LOBE ROTATING ON THE BACK SIDE OF THE UPPER LOW. THIS AREA OF MORE WIDESPREAD CLOUDINESS/ SCATTERED PRECIP IS CURRENTLY N OF LAKE HURON ACROSS ONTARIO...MOVING SOUTH. OTHERWISE...PRECIP PROBABILITIES ACROSS THE WESTERN SIDE OF ERN UPR/NRN LWR MI WILL BE PRIMARILY IN THE EVENING. HIGHLY-AMPLIFIED UPPER FLOW PATTERN CONTINUES ON WED...THOUGH WITH CLOSED LOW PULLING A LITTLE FARTHER EAST OF THE REGION. THE Q-G CHARTS SHOW INCREASED UPPER CONVERGENCE/SUBSIDENCE AS THE UPPER HEIGHTS BUILD BEHIND THE TROUGH. WITH THE INCREASED SUBSIDENCE... MODEL SOUNDINGS SHOW THE LOWER-MID LAYERS DRYING OUT WITH... DESPITE SIMILAR 925-850 MB TEMPS AS TODAY...WARMER TEMPS BETWEEN 800-500 MB (LOWERING SUBSIDENCE INVERSION). THIS WILL LIMIT THE EXTENT/ DEPTH OF DIURNAL CLOUD COVER AS THE DAY PROGRESSES...THUS HAVE WORDED BECOMING MOSTLY SUNNY IN ALL ZONES BY AFTERNOON. MUCH THE SAME STORY WED NIGHT AND THU...WITH DRY WEATHER TO CONTINUE AS REGION REMAINS IN BETWEEN UPPER RIDGE AND TROUGH AXES (MAINTAINING THE UPPER CONVERGENCE/Q-VECTOR DIVERGENCE/SUBSIDENCE). EXTENDED DISCUSSION...MRF AND ECMWF CONTINUE TO BE IN DECENT ACCORD THROUGH THE WEEKEND WITH OVERALL UPPER FLOW PATTERN...THOUGH WITH ECMWF SURFACE FEATURES DO NOT MATCH UP AS WELL WITH UPPER LEVEL FEATURES. CANADIAN ENSEMBLES HAVE BEEN CONSISTENT OF LATE...HOWEVER THIS MODEL REMAINS THE OUTLIER COMPARED TO THE MRF/ECMWF FROM SUN THROUGH TUE. CANADIAN SHOWS A REX BLOCK BY SUN OVER THE WEST (RIDGE OVERTOP CUTOFF LOW)...WITH A TROUGH ACROSS THE ERN CONUS. THE MRF AND ECMWF INSTEAD SHOW A MEAN TROUGH OUT WEST (WITH CLOSED LOW IN THE SWRN STATES AS WELL)...WITH RIDGE BUILDING IN THE ERN CONUS ON SUN FOLLOWING INITIAL SHORTWAVE ON SAT. GIVEN MODEL TRENDS OVER THE PAST COUPLE OF DAYS...WITH THE ACTIVE NRN BRANCH ACROSS THE PACIFIC NW... WILL AGAIN FOLLOW MRF/ECMWF SOLUTIONS. THE INITIAL EXTENDED FORECAST CONCERN IS WITH RAIN CHANCES ON FRI ASSOCIATED WITH WEAK NRN STREAM SHORTWAVE. EXTENDED RUNS...ALONG WITH LATEST (12Z) AVN...HAVE ALL TRENDED TOWARD A SLOWER EWRD PROGRESSION OF THIS FEATURE...WITH THE SFC TROUGH NOW PROGGED TO REACH THE WESTERN PTN OF LOWER MI BY 12Z SAT. WITH THE LOW-LEVEL RIDGING/DRY AIR LIKELY TO HANG ON DURING THE DAY FRIDAY...HAVE RE-WORDED RAIN CHANCES FOR THE OVERNIGHT FRI-SAT. TRICKER FORECAST IS WITH SUN AHEAD OF MAIN SYSTEM. AGAIN...MRF AND ECMWF SHOW BUILDING HEIGHTS BEHIND INITIAL VORT LOBE AND NEXT (MAIN) UPPER TROUGH. THIS WOULD SPELL A WARMUP ALONG WITH MINIMAL RAIN CHANCES ON SUN AND PERHAPS MOST OF MON (WAA/ISENTROPIC LIFT IS NOTED...THOUGH MOISTURE APPEARS LIMITED). HOWEVER...GIVEN THE SO-SO RUN-TO-RUN CONTINUITY OF LATE...WILL FOR NOW MAINTAIN A CHANCE OF SHOWERS WITH THE DEVELOPING WARM ADVECTION PATTERN. .APX...NONE. HURLEY mi FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 955 AM CST TUE MAR 28 2000 FORECAST CHALLENGE FOR UPDATE CONCERNS CLOUD TREND AND TEMPS. VIS LOOP INDICATING BACK EDGE OF SC DECK OVR ARROWHEAD REGRESSING WEST SLIGHTLY ASSOCIATED WITH WK SFC TROUGH VCNTY LAKE SUPERIOR. RUC HINTED AT THIS LOOKING AT H925 MB RH BUT AS STACKED SYSTEM SHIFTS EAST TODAY WOULD NOT EXPECT MUCH MORE OF A WESTWARD SHIFT. LATEST SCANS FROM VIS ALSO SHOWING SOME EROSION ALONG THE WESTERN EDGE. WITH CYC FLOW CONTINUING AND SHALLOW LAYER OF GREATER RH FROM RUC MODEL SOUNDING AT H9-85 COULD SEE SOME CU DEVELOP ALTHOUGH H85 TEMPS NOT NEARLY AS COLD AS YSTDY AND CU RULES NOT VERY IMPRESSIVE. CURRENT FCST HAS PC OVR FAR EAST AND WILL CONTINUE TREND. REAMAINDER OF REGION SHOULD SEE NEARLY FULL SUN. TEMP ADVECTION FAIRLY NEUTRAL AND NOT ALOT OF MIXING WITH SFC HIGH OVR AREA. CURRENT READINGS FAIRLY UNIFORM ACROSS THE FA AND INLINE WITH FWC GUIDANCE SO NO SIG CHANGES PLANNED. SLIGHTLY STRONGER WINDS OVR EASTERN FA DEEPER IN CYC FLOW. .FGF...NONE. VOELKER nd