EAST CENTRAL FLORIDA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 855 PM EST THU FEB 17 2000 CURRENTLY...SKIES ARE MOSTLY CLEAR OVER FORECAST AREA...HOWEVER SCT-BKN LOW CLOUDS EXIST FROM VERO BEACH SOUTH. WINDS ARE GENERALLY EAST AROUND 5 MPH OR CALM. A FRONTAL BOUNDARY IS MEANDERING OVER NORTHERN FLORIDA AND SOUTHERN GEORGIA A WITH LARGE SURFACE RIDGE AXIS OVER CENTRAL FLORIDA. TEMPERATURES ACROSS THE AREA ARE RANGING FROM THE MID 60S TO AROUND 70. DISCUSSION...LATEST RUC MODEL SHOWS BOUNDARY LAYER WINDS PICKING UP SPEED TOWARDS MORNING. PATCHY GROUND FOG WILL POSSIBLE OVER NORTHERN PORTIONS OF FORECAST AREA...ESPECIALLY VOLUSIA COUNTY DUE TO CALM WINDS AND 1 DEGREE DEWPOINT DEPRESSION PRESENTLY. I WILL THROW IN SOME PATCHY FOG FOR VOLUSIA COUNTY AND REST OF THE FORECAST LOOKS GREAT. MARINE...LATEST 8 PM 41009 BUOY DATA INDICATES EAST WINDS AT 12 KNOTS WITH 3 FOOT SEAS. CURRENT CWF LOOKS ON TRACK WITH LITTLE ADJUSTMENT NEEDED. .MLB...NONE. JMB fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 828 PM EST THU FEB 17 2000 ZFP/MODELS: MAIN CONCERNS THIS UPDATE ARE POPS AND FOG POTENTIAL. EARLY THIS EVENING...A FEW SHOWERS POPPED UP ALONG THE SEA BREEZE FRONT AND HAVE SINCE DISSIPATED N OF VLD. CURRENTLY...NEAREST CONVECTION CONFINED TO AREAS N OF A SLOWLY RETREATING WRM FRONT JUST N OF THE CWFA IN CENTRAL AL/GA. OTHER TSRA IN E CENTRAL MS MOVING SLOWLY ENE. 12Z NGM AND 18Z ETA BOTH SHOWED UVVELS MAXING OUT AROUND 00Z WITH OTHER MODELS SHOWING WEAK IF ANY LIFT. THIS MAKE SENSE WITH CURRENT FRONTAL POSITION RELEGATING ANY ISENTROPIC LIFT TO AREAS N OF OUR CWFA. LATEST RUC AND 18Z ETA BOTH SHOWED THE SMALL SHORT WAVE OVER S MS (THAT IS SPARKING CONVECTION IN THAT AREA) WEAKENING AS IT LIFTS NE THIS EVENING. THEREFORE PLAN TO REMOVE POPS FROM ALL OF MY ZONES. LATEST FOG PRODUCT SHOWS TODAY/S ST CONTINUING TO SLOWLY DIMINISH IN COVERAGE ACROSS THE PANHANDLE AND SE AL WITH MOCLR SKIES ACROSS MUCH OF THE BIG BEND AND PARTS OF SW GA. ALL THESE BREAKS WILL DO IS HASTEN ARE TRIP TO A ZERO TDD. ANOTHER BANK OF LOW ST AND FG IS MOVING W FROM JAX WITH SOME VSBYS BELOW 1 NM IN JAX ALREADY (CRG). MVFR VSBY HAS RETURN TO AQQ WITH CEILINGS BELOW 500 FT. WINDS HAVE ALREADY DECOUPLED IN MOST OF OUR FL ZONES. UPSHOT IS THAT WE EXPECT ANOTHER ROUND OF FOG OVERNIGHT. MOS NUMBERS INDICATE THAT IT WILL BE DENSE. WILL HOLD OFF OF ISSUING ANY DENSE FOG ADVY THIS EARLY...BUT WILL INSERT DENSE FOG WORDING IN ZONES AND MONITOR FOR POSSIBLE NPW ISSUANCE LATER IN THE SHIFT OR ON MID SHIFT. WILL BREAK OUT EASTERN ZONES TO ACCOUNT FOR ST/FG APPROACHING THAT AREA AND SLIGHTLY LOWER MINS. ALSO PLAN TO RAISE MINS A TAD W OF THE RIVER. MARINE: NO MAJOR CHANGES PLANNED HERE. .TLH... AL...NONE. GA...NONE. FL...NONE. MAW fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSONVILLE FL 941 AM EST THU FEB 17 2000 FOG CONTINUING TO REDUCE VISIBILITIES WEST AND SOUTH CWA. WILL UPDATE FORECAST PACKAGE TO REMOVE MENTION OF MORNING FOG AFTER DISSIPATION IN THOSE AREAS. WEAK FRONT NOTED OVER CENTRAL GEORGIA THIS MORNING AS HIGH PRESSURE REMAINS SOUTH. NORTHEAST TO EAST WINDS TODAY WITH PARTLY CLOUDY SKIES. CLOUDS ADVERTISED ON THE INCREASE TODAY FOR NORTH CWA BY PREVIOUS MODELS...BUT THIS MORNINGS' RUC NOT INITIALIZING WELL AND WILL PUT IN PARTLY CLOUDY THERE INSTEAD. WILL BUMP UP TEMPS AS LITTLE AS A RESULT. WILL CONTINUE TREND IN MARINE. SCEC CONDITIONS EXPECTED OFFSHORE AND AN INCREASE BUT BELOW CRITERIA NEAR SHORE. 11 .JAX... GA...NONE. FL...NONE. fl EAST CENTRAL FLORIDA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 930 AM EST THU FEB 17 2000 THIS AFTERNOON...TAMPA SOUNDING SHOWED LESS DRY AIR IN THE LOW LEVELS COMPARED TO THE LAST FEW DAYS...BUT CANAVERAL SOUNDING CONTINUED WITH SHALLOW MOISTURE AND EXTENSIVE DRYING ABOVE. MODELS INDICATE THAT MOISTURE OVER THE EASTERN GULF WILL ADVECT WESTWARD WITH DEEP DRY AIR OVER CENTRAL FLORIDA. THEREFORE WILL GO WITH MOSTLY SUNNY SKIES. OTHERWISE WILL JUST CHANGE TEMPS TO SHOW A BEACHES/INLAND CONTRAST. FIRE WX...ONSHORE FLOW WILL KEEP RH VALUES WELL ABOVE CRITICAL LEVELS IN THE COASTAL COUNTIES. HOWEVER...DRY AIR JUST ABOVE THE SURFACE WILL MIX DOWN OVER INTERIOR SECTIONS...ALLOWING MINIMUM RH VALUES TO REACH 35 PERCENT FOR A BRIEF PERIOD THIS AFTERNOON. MARINE...HIGH PRESSURE RIDGE WEAKENING OVER THE WATERS PROVIDING VARIABLE AND LIGHT WINDS. THEY SHOULD BECOME ONSHORE AT NO MORE THAN 10 KNOTS THIS AFTERNOON AS PER RUC AND MESO ETA MODELS. STALLING FRONT OVER NORTHEAST FLORIDA SHOULD BOTTLE UP THE GRADIENT INCREASE TO THE NORTH OF OUR WATERS. .MLB...NONE. KELLY/LASCODY fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CARIBOU ME 942 AM EST THU FEB 17 2000 SYNOPSIS: LOW PRESSURE WILL LIFT TOWARD NEWFOUNDLAND THIS AFTERNOON WHILE HIGH PRESSURE BUILDS TOWARD NEW ENGLAND FROM THE GREAT LAKES. THE HIGH WILL MOVE EAST OF THE REGION OVERNIGHT. A DEVELOPING WINTER STORM WILL MOVE TO THE OHIO RIVER VALLEY BY FRIDAY EVENING. TECHNICAL DISCUSSION: CONCERN THIS AFTN WILL BE WIND CHILL ADV/TEMPS. WILL DISCUSS WKEND EVENT IN AFTN AFD. WRKZFP SENT. AS MNTND BY MID-SHIFT...TEMPS FELL SHARPLY BEFORE DAYBREAK DUE TO STG VORT MAX/CAA. CAA & NW WINDS AVGG 15-25 MPH W/GUST TO 30 CAUSING WIND CHILLS TO BE AOB CRITERIA. WINDS SHOULD SLOWLY SUBSIDE LATE THIS AFTN AS HIGH PRES RIDGES OVER THE CWFA. LATEST RUC2/MESO-ETA INDICATE WINDS TO STAY UP & CAA TO CONT THRU 21Z. WILL HOLD ONTO WIND CHILL ADV THIS AFTN ESP NRN ZNS. MGT NEED TO ADJUST AFTN TEMPS DOWN A NOTCH. 12Z RAOB/RUC SNDG GIVES MAKE 10-15 FOR NRN ZNS. WILL MAKE FINAL DECISION AFT 10Z OBS. HIGH SUN ANGLE SHOULD HELP WARM BLYR SOME. COASTAL WATERS: GALE CONDS OUT THERE ON THE WTRS ATTM. RUC2 SHOWS WINDS HOLDING @ 30 KTS THRU 21Z W/THAT CAA COMING OVER THE WTRS. PER DISC W/MARINE GUY WILL KEEP GLW FOR EARLY THIS AFTN & BRING WINDS DOWN LATE. .CAR...WIND CHILL ADVISORY THIS MORNING FOR ZONES 001>006-010-011 GLW FOR COASTAL WATERS. JOE me AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 1039 PM EST THU FEB 17 2000 CURRENT REGIONAL RADAR AND SURFACE REPORTS FROM EAST UPPER AND NORTHERN LOWER MICHIGAN...SHOW THE AREA OF LIGHT SNOW THAT AFFECTED THE REGION EARLIER THIS EVENING HAS NOW DIMINISHED BOTH IN AREAL COVERAGE AND INTENSITY. CURRENT SURFACE REPORTS JUST SHOW FLURRIES OF SCATTERED LIGHT SNOW SHOWERS AFFECTING THE SOUTHERN PORTIONS OF THE FORECAST AREA. THE MAIN FORECAST QUESTION TONIGHT WILL BE THE TIMING OF THE MAIN BATCH OF SNOW INTO THE FORECAST AREA. REGIONAL RADAR DATA SHOWS AN AREA OF LIGHT SNOW REDEVELOPING OVER SOUTHWEST LOWER MICHIGAN AND INDIANA IN ADVANCE OF A 500 MB VORT LOBE MOVING NORTHWARD. HOWEVER THE MAIN AREA OF SNOW IS STILL WELL SOUTH OF THE FORECAST IN ADVANCE OF THE SFC LOW PRESSURE SYSTEM MOVING OUT OF CENTRAL PLAINS. THE LATEST RUC PULLS THE SURFACE LOW INTO WEST ILL BY 12Z FRIDAY WITH SURFACE WIND CONVERGENCE AHEAD OF THIS SYSTEM BUILDING INTO CENTRAL LOWER MICHIGAN OVERNIGHT. UPPER LEVEL DIVERGENCE IN THE RIGHT ENTRANCE REGION OF THE UPPER JET MOVING OVER THE STRAITS... SEEMS TO BE FOCUSED SOUTH OF THE FORECAST AREA OVERNIGHT AND EARLY FRIDAY MORNING. THIS WILL FOCUS THE MOST PERSISTENT SNOWFALL OVER SOUTHERN LOWER MICHIGAN AND THE EXTREME SOUTHERN PORTIONS OF THE APX CWA. DUE TO THE LATEST RADAR AND SURFACE OBSERVATIONS...WILL LIMIT THE CATEGORICAL SNOWFALL TO THE SOUTHERN PARTS OF THE FORECAST AREA WITH SCATTERED CHANCES AROUND APX AND APN. FOR THE STRAITS AND EAST UPPER WILL GO WITH A FEW SNOW SHOWERS OR FLURRIES. .APX...NONE. SWR mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1000 PM EST THU FEB 17 2000 ...INCREASE WARNING AREA ONE SET OF COUNTIES NORTH AND DELAY START OF HEAVY SNOW TILL FRIDAY... LOOKING AT THE LATEST SFC DATA AND COMPARING IT TO MODELS... SEEMS THE 12Z ETA WAS TO FAST WITH THE TRACK OF THE SYSTEM AND BRINGING THE PRECIPITATION INTO LWR MI. LATEST FCST FROM HPC AGREES SUGGEST THE HEAVY SNOW WILL BE IN TO COMMA HEAD BAND WHICH WILL CROSS CENTRAL LOWER MICHIGAN DURING FRIDAY. IF ANYTHING... THE SNOW WILL LAST WELL INTO FRIDAY NIGHT. THIS WILL ALLOW MORE ACCUMULATIONS FARTHER N. WILL NOT PUT CHANGE 3D PERIOD HOWEVER. BUT WILL INCREASE SNOWFALL OVER ALL BUT EXTREME SOUTH ABOUT AN INCH. THUS WILL HAVE TO PUT NEXT TIER OF COUNTIES INTO WARNING SINCE THAT WILL GIVE THEM 5 TO 7 INCHES. GRR/LAN WILL SEE 6 TO 10 INCHES. SOME QUESTION ABOUT CHANGE OVER IN I-94 AREA... SO WILL TAPPER AMOUNTS BACK SOME AND SUGGEST POSSIBLE COMPLETE CHANGE OVER FOR AWHILE DURING THE MORNING. AS FOR TIMING TONIGHT... USING THE 850/700 MEAN RH FROM THE RUC... WHICH IS MATCHING WELL WITH CURRENT PCPN AREA... SNOW WILL NOT REALLY GET STARTED OVER MOST OF CWA TILL AFTER 09Z... SO WILL HAVE SRN SET OF COUNTIES WARNING START LATE TONIGHT AND GRR AREA AND NORTH HAVE IT FOR FRIDAY ONLY. .GRR...WINTER STORM WARNING...OCEANA...NEWAYGO...MECOSTA...ISABELLA FOR FRIDAY WITH 5 TO 7 INCHES. BETWEEN I-96 AND I-94 WILL HAVE WINTER STORM WARNING FRIDAY FOR 6 TO 10 INCHES OF SNOW. I-94 COUNTIES WILL HAVE WINTER STORM WARNING LATE TONIGHT AND FRIDAY FOR 5 TO 8 INCHES WITH POSSIBLE CHANGE TO FREEZING RAIN AND SLEET DURING THE LATE MORNING AND EARLY AFTERNOON. SNOW ADVISORY FRIDAY FOR MASON...LAKE...OSCEOLA AND CLARE FOR 3-6 INCHES. WDM mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 1040 AM EST THU FEB 17 2000 ONLY BIG CHANGE FOR THIS AFTERNOON WILL BE TO ADD FLURRIES TO THE NORTH. AT 15Z...HIGH OVER SOUTHERN ONTARIO. LOW PRESSURE IN SOUTHERN ROCKIES WITH MAIN WARM FRONT MOVING ACROSS KS...BUT SEEMS TO BE SECONDARY WARM FRONT ACROSS NORTHERN PLAINS FROM SD TO NRN IL. ISENTROPIC LIFT/WAA LIGHT SNOW FALLING NORTH OF THIS BOUNDARY IN MN AND NORTHERN WISCONSIN. AREA OF ISENT LIFT MOVES OVER NORTHERN HALF OF CWA THIS AFTERNOON WHILE LOW LEVELS MOISTEN UP SOME. 12Z RUC SHOWS CONDENSATION PRESSURE DEFICITS BELOW 40MB THIS AFTERNOON ACROSS NORTHERN NORTHERN LOWER AND EASTERN UPPER. TEMPERATURES LOOK GOOD BASED ON CURRENT READINGS VS. MOS 15Z FCST. WINDS WILL REMAIN LIGHT UNTIL GRADIENT PICKS UP LATER THIS AFTERNOON AS HIGH PRESSURE MOVES AWAY. SYNOPTIC SNOW TO MOVE IN THIS EVENING...BUT OHIO VALLEY CONVECTION WILL NEED TO BE WATCHED. MAIN AREA OF FORCING WILL BE WELL SOUTH OF REGION AND EVEN BEST ISENT LIFT WILL BE ACROSS CENTRAL AND SOUTHERN MICHIGAN. IF MOISTURE HAS A HARD TIME MOVING UP FROM THE SOUTH...MIGHT TURN OUT TO BE PRETTY LIGHT SNOW. .APX...NONE. FARINA mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 830 PM CST THU FEB 17 2000 FORECAST CONCERN NEAR TERM...SNOW OVER FAR SOUTHERN CWA. RADAR SHOWING DECREASING TREND TO SNOW AREA OVER CENTRAL CWA. PERSISTENT SNOW BANDS ASSOCIATED WITH UPPER JET STREAM. THE 21Z RUC SHOWS THE UPPER JET IS FORECAST TO SHIFT OVER IOWA TOWARD MIDNIGHT. LATEST SATELLITE SHOWS SOME COOLING OF TOPS BEGINNING TO MOVE BACK INTO SOUTHERN MN AS THE UPPER TROF BEGINS TO LIFT NORTHEAST. STILL THINK COULD SEE SOME GOOD SNOWS CLOSE TO THE MN/IA BORDER AREA...NEAR ALBERT LEA BEFORE MORNING. MAY UP THE SNOW FORECAST AT BIT THERE. OTHERWISE FLURRIES EXPECTED ELSEWHERE. .MSP...NONE. DWE mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 1030 AM CST THU FEB 17 2000 SHORT TERM TREND OF FCST APPEARS TO BE ON TRACK...AND WILL GENERALLY LEAVE IT ALONE EXCEPT FOR SOME WORDING CHANGES. HEAVIEST SNOW THUS FAR HAS BEEN IN THE MKT/ULM AREAS WITH AROUND 3 INCHES. 12Z RUC DEPICTING THE NRN EDGE OF 850 MB WAA AND AN AREA OF W TO E DIVERGENCE ALONG SRN EDGE OF 300 MB JET STREAK OVR SRN MN. IN ADDITION...FAIRLY LINEAR JET STREAK SHOULD HAVE A WELL DEVELOPED DIRECT THERMAL CIRCULATION OVR MN...WITH ASCENT OVR SRN AREAS AND SUBSIDENCE IN CNTRL MN. LONG LOOP OF 88D SHOWS SUCH A TREND OVR THE LAST FEW HRS. WOULD EXPECT TO LOSE NEARLY ALL JET SUPPORT AS THE CORE MOVES EAST OF MN...WHICH IS ALREADY OCCURRING PER WOOD LAKE PROFILER AND 6.7 WATER VAPOR LOOP. NEXT QUESTION WILL BE HOW MUCH ADDITIONAL LIFT WILL BE REALIZED FROM DOWNSTREAM JET STREAK OVR WRN KS. THIS FEATURE ISN'T WELL DEPICTED ON ETA...BUT THERE IS SOME HINT OF IT MOVING NE AND INTENSIFYING OVR IA. THIS WOULD PLACE LEFT EXIT REGION ACRS NRN IA/SRN MN...SO EXPECT ANOTHER ROUND OF -SN FOR FAR SRN MN THIS EVENING. HOWEVER...INTENSIFYING CONVECTION OVR SRN PLAINS AND SPEED OF JET STREAK WILL LIMIT THE SNOWFALL POTENTIAL TO BELOW ADVISORY CATEGORY. .MSP...NONE. DAVIS mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTH PLATTE NE 102 PM CST THU FEB 17 2000 FORECAST CHALLENGE REMAINS SNOW AMOUNTS THROUGH FRIDAY MORNING. LOW DEGREE OF CONFIDENCE IN ANY OF THE MODEL DATA FORECAST DUE TO POOR VERIFICATION OF THIS MORNING/S DRY SLOT SCENARIO. NGM SNOW ACCUMULATOR LOOKS TO BE THE ONLY ONE CLOSE TO REALITY AS OF 18Z THURSDAY...BUT IT ALSO MISSED MORNING SNOW OVER NORTHEAST ZONES. NGM IS TRENDING MORE TOWARDS YESTERDAY/S ETA SOLUTION TAKING SURFACE LOW FARTHER SOUTH TO TEXAS PANHANDLE BY 00Z FRI. ALL MODELS AGREE ON BEST SNOW AT MIDNIGHT TONIGHT FOR CENTRAL PART OF CWA. MODELS HAVE CONSISTENTLY SLOWED DOWN SECOND WAVE FOR EACH RUN OVER THE PAST COUPLE DAYS. THIS SECOND SYSTEM IS BECOMING MOISTURE STARVED PER THE ETA OVER OUR AREA AS WELL. HEAVY SNOW DISCUSSION MENTIONS CENTRAL COLORADO. SAT PIX SHOWS UPPER LEVEL VORT MAX IN SC CO PROGGED TO HEAD EAST SOUTHEAST. RUC HAS NOT BEEN ON TARGET THIS MORNING WITH PRECIP FIELDS EITHER. AM LEANING TOWARDS THE ETA SOLUTION FOR EARLIER PERIODS...BLENDING ALL TOWARDS LATTER HALF OF FORECAST. TONIGHT...ISENTROPIC DOWN GLIDE AGREED UPON BY ALL MODELS AT 295K SURFACE OVERNIGHT...AT LEAST OVER NORTHWEST HALF OF STATE. BEST LIFT (OMEGA...QG FORCING...AND WAA) STAYS IN KANSAS TOWARDS TOPEKA WITH NEUTRAL OR NEGATIVE OMEGA OVER US AT 06Z. LOOKS LIKE WE WILL GET INTO SOME WRAP AROUND WHICH COULD PRODUCE A FEW INCHES. THINK IT MAY BE PRUDENT TO KEEP ADVISORY GOING FOR SOUTHERN AND EASTERN ZONES IN CASE THERE ARE SOME ISOLATED 4 INCH AMOUNTS OVERNIGHT. WILL WORD AS 3 TO 5 INCHES. SURFACE HIGH BUILDS INTO WESTERN ZONES BY 12Z WITH NORTH WIND AND CAA...SO THIS IS EXPECTED TO SHUT OFF THE SNOW THERE. FRIDAY/NIGHT...SNOW ENDING BY MID MORNING OVER ALL OF CWA AS SYSTEM QUICKLY MOVES EAST. NGM LAPSE RATES MUCH STEEPER THAN ETA/S AS FAR AS POSSIBLE COLD AIR STRATO CU DEVELOPMENT DURING THE AFTERNOON. PLENTY COLD WITH 850 TEMPS AVERAGING -8 TO -5 C THROUGH FRIDAY AFTERNOON. WILL TAKE OUT MORNING FLURRIES FOR ALL ZONES MOST LIKELY. REST OF THE DAY SHOULD BE MOSTLY SUNNY UNLESS STRATO CU DEVELOPS PER THE NGM. WILL HAVE TO WATCH FOR ISOLD SNOW SHOWERS. SATURDAY...LOOKS MOSTLY SUNNY. RH FIELDS THROUGHOUT ATMOSPHERE LESS THAN 50% FOR ENTIRE ARE ALL DAY AS WEAK RIDGING TAKES PLACE OVER HIGH PLAINS. RIDGING SEEMS TO BE IN RESPONSE TO CUT OFF LOW OFF CALIFORNIA COAST DIGGING INTO SOUTHERN CA BY 12Z SUNDAY. WEAK DISTURBANCES DO ZIP THROUGH DURING THE DAY OVER AREA...BUT ARE SINCE WE ARE ON THE EAST SIDE OF THE RIDGE AXIS...WE WILL BE LACKING ADEQUATE MOISTURE TO PRODUCE ANYTHING. EXTENDED...SUNDAY THROUGH TUESDAY THE RIDGE BEGINS TO BREAK DOWN SOME AS SYSTEM TRIES TO MOVE ASHORE. APPEARS TO REMAIN NEARLY STATIONARY BEFORE FINALLY COMING ASHORE IN MEXICO TUESDAY MORNING. WITH CUT OFF LOWS...HAVE SEEN USUAL TENDENCY FOR MODELS TO TRY TO BRING THEM ASHORE TOO QUICKLY AND EXPECT THIS IS NO EXCEPTION. LOOKS DRY THROUGH PERIOD WITH A BIT OF A WARM UP. .LBF...SNOW ADVISORY TONIGHT SW TO NE... ZONES 007-010-026>029-037-038-056>059-069>071... SLM ne AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE MIDLAND TX 904 PM CST THU FEB 17 2000 THE LATEST SFC ANALYSIS SHOWS THE DRYLINE HAS BACKED UP TO WEST OF ODESSA...AND THEN BETWEEN FORT STOCKTON AND DRYDEN. SPC DIAGNOSTIC FIELDS SHOW AN AREA OF ENHANCED LOW LVL MSTR CONVERGENCE ALONG THIS DRYLINE OVER PORTIONS OF THE ERN PERMIAN BASIN...BIG COUNTRY...AND THE LOW ROLLING PLAINS. THIS AREA APPEARS TOO CAPPED OFF TO GET ANY THUNDERSTORMS GOING...AND WITH THE ONSET OF NIGHTTIME AND LITTLE IN THE WAY OF UPPER LEVEL FORCING...EXPECT THUNDERSTORM CHANCES WILL CONTINUE TO DWINDLE. SFC WINDS HAVE BACKED TO THE SOUTH OVER PORTIONS OF THE PERMIAN BASIN...EAST OF THE DRYLINE. I WILL MAKE SLIGHT ADJUSTMENTS IN THE ZONES TO REFLECT THE PRESENT WIND DIRECTION. 00Z RUC DATA DOES INDICATE THAT THE DRYLINE WILL PUSH EAST OF THE FORECAST AREA AGAIN OVERNIGHT...AS A PACIFIC FRONT PUSHES INTO THE AREA...SO WIND FORECASTS IN THE LONGER TERM STILL SEEM ON TRACK. SFC LOW PRESSURE CENTERED OVER THE EASTERN TX PNHDL AND WESTERN OK BORDER WILL CONTINUE TO MOVE EAST AWAY FROM THE FORECAST AREA...AS THE LOW LVL PRESSURE GRADIENT RELAXES AND WINDS IN THE GUADALUPE AND DAVIS MOUNTAINS CONTINUE TO DIMINISH TO BELOW WARNING THRESHOLDS. HIGH WIND WARNINGS FOR THESE AREAS ARE IN THE PROCESS OF BEING CANCELLED. .MAF... TX...NONE. NM...NONE. PV/03 tx TEXAS/OKLAHOMA PANHANDLES FORECAST DISCUSSION NATIONAL WEATHER SERVICE AMARILLO TX 1143 AM CST THU FEB 17 2000 15Z SFC ANALYS SHOWED LOW DEVELOPING ACROSS SE CO WITH PAC FNT INTO CNTRL NM. WMFNT FM N MAF TO ALONG RED RIVER BEGINNING TO MOVE N IN RESPONSE TO APPROACHING UPPER LEVEL STORM MOVING THROUGH FOUR CORNERS. EXPECT SFC LOW TO DEEPEN AND MOVE E ACROSS MAINLY OK PNHDL THIS AFTN AND EXIT FA AFT 00Z. STRONG RETURN OF LLVL MOISTURE NOTED ACROSS CENTRAL TX WITH DPS ABV 60 ALREADY INTO N TX ALONG WMFNT. EXPECT AIRMASS ACROSS ERN 1/3 TX PANHANDLE TO CONTINUE TO DESTABILIZE THIS AFTN AS CLEARING SEEN ON VIS IMAGERY OVER SE CORNER FA WORKS N. INITIALLY ELEVATED BKN LINE OF CONVECTION SHOULD FORM ALONG/AHEAD OF WMFNT THIS AFTN ACROSS ERN ZNS AND MOVE RAPIDLY E AS ADVERTISED IN EARLIER PACKAGE. LTG DATA INDICATES STRIKES ALONG NM/CO BORDER ASSCD WITH LIFT AHEAD OF UPPER STORM. THIS SHOULD WORK E AND NE THIS AFTN SO WILL KEEP SOME SLIGHT MENTION OF THUNDER IN FAR NRN ZNS WITH SLIGHT CHC S CENTRAL NEAR INITIATION. OTHER MAJOR CONCERN IS WITH WIND. 12Z RUC INDICATES STRONG H7 GRADIENT MOVING OUT OF ERN NM THIS AFTN. WHITE SANDS PROFILER SUPPORTS THIS WITH 50KT WINDS JUST ABV H8. SFC WINDS ACROSS ERN SLOPES NM ALREADY IN ADVISORY BEHIND PACFNT SO EXPECT THIS TO CONTINUE MIGRATING EWRD THIS AFTN. WILL ISSUE WIND ADVSY FOR WRN 2/3 TX/OK PNHDLS THIS AFTN. ALSO RAISED TEMPS A NOTCH WITH CURRENT OBS/NEW FWC GUIDANCE SUPPORTING A BIT WARMER TEMPS BEHIND FNT THIS AFTN. .AMA... TX...WIND ADVISORY THIS AFTN ZNS 001>003-006>008-011>013-016>018. OK...WIND ADVISORY THIS AFTN ZNS 001-002. COBB tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 920 PM EST THU FEB 17 2000 RADAR COMPOSITE IS SHOWING LEADING EDGE OF LARGE AREA OF PCPN INTO EXTREME SW VA AT 02Z. SEEMS LIKE ONCE CIGS DROP BELOW 5-6KFT THE PCPN STARTS REACHING THE GROUND. LIKE TIMING OF PCPN FM LATEST RUC WHICH HAD LEADING EDGE TO ROUGHLY A ROA TO DAN BY 1AM THEN SPREADING ACRS THE ERN PASRT OF THE CWA BY 4AM. SO WL ADJUST WORDING IN THE ZONES. A LITTLE CONCERNED ABOUT PCPN TYPE. SFC TEMPS ARE STILL IN THE MID 30S TO LOW 40S...BUT THE RUC HAD WET BULB TEMPS STILL BELOW FREEZING AFT 06Z. NO CHANGES TO LATER PERIODS. .RNK VA...WINTER WEATHER ADVISORY LATE TONIGHT AND FRIDAY VAZ018>020-022>024-034-035-045>047. WV...WINTER WEATHER ADVISORY LATE TONIGHT AND FRIDAY WVZ044-045. NC...NONE. AMS va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 1247 PM CST THU FEB 17 2000 ...DISCUSSION DELAYED DUE TO SOFTWARE PROBLEMS... SATELLITE IMAGERY...RADAR AND SURFACE OBSERVATIONS DEPICTING TWO DISTINCT AREAS OF SNOW AFFECTING THE FORECAST AREA. TO THE NORTH... SNOW BAND HAS DEVELOPED IN DEFORMATION AREA OF THE LEADING SHORTWAVE AND HAS PRODUCED 1 TO 3 INCHES ACROSS MINNESOTA. THIS ACTIVITY IS HANDLED WELL BY THE RUC...AND SHOULD AFFECT THE NORTHERN PORTION OF THE FORECAST AREA THIS AFTERNOON. TO THE SOUTH...RADAR IMAGERY SHOWING BAND OF PRECIPITATION SETTING UP TO THE WEST OF THE SOUTHERN ZONES...OR IN NORTHERN IOWA. THIS ACTIVITY SHOULD MOVE INTO THE FORECAST AREA AND EVENTUALLY BECOME THE MAIN DEFORMATION BAND LATER TONIGHT. THUS HAVE UPGRADED THE WATCH TO A WARNING AND HAVE ISSUED AN ADVISORY FOR THE COUNTIES JUST NORTH OF THE WARNING AREA. COORDINATED WITH MKX/DMX/DVN. .LSE...WINTER STORM WARNING FOR TONIGHT THROUGH FRIDAY MORNING... IAZ029-030-WIZ061. WINTER WEATHER ADVISORY FOR TONIGHT THROUGH FRIDAY MORNING... IAZ001>011-IAZ018-019-WIZ054-055. KRC wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 935 PM CST THU FEB 17 2000 STILL LOOKS GOOD FOR A DECENT SNOW EVENT ACROSS MUCH OF THE CWA TONIGHT WITH ICE ACROSS SOUTHERN AREAS. 88D REFL INCREASING RAPIDLY NOW AS STRONG WAA CONTINUES. NICE WEDGE OF WARM AIR MOVING INTO IA ABOVE THE SURFACE WITH MANY LOCATIONS ACRS THE S NOW REPORTING FREEZING RAIN. RWIS DATA SHOWS ROAD TEMPS STILL ABOVE FREEZING FAR SOUTH BUT ANY OBJECT NOT IN CONTACT WITH THE GROUND IS PROBABLY RECEIVING A NICE GLAZING. UPDATED ZONES AND WSW TO HIT FREEZING RAIN A BIT HARDER IN THE SOUTH AS IT APPEARS THE TRANSITION TO SNOW WILL BE LATER TONIGHT. FARTHER NORTH...DEF ZONE APPEARS TO BE SETTING UP FROM W CENTRAL ZONES UP TO NEAR ALO. WL KEEP ON WITH WARNING IN THESE AREAS WITH 6 TO 10 STILL LOOKING GOOD. NEW ETA AND RUC SHOW BEST DYNAMICS FROM 06Z TO A LITTLE AFTER 14Z SO SHOULD SEE A NICE 6 TO 10 HOUR STRETCH OF HEAVIER SNOW WITH SOME LIGHTER SNOWS THEREAFTER. ADJUSTED AMOUNTS IN ADVISORY AREA JUST SLIGHTLY AS ESTHERVILLE PROBABLY DONE WITH HEAVIER SNOW FOR NOW. LEFT REST ALONE. .DSM...SNOW ADVY NRN IA TNGT INTO FRI AM...IAZ004>007-015>017-023>025 WNTR STORM WRNG TNGT INTO FRI AM...IAZ026>028-033>039-044>050- 057>062-070>075-081>086-092>097 $$ COGIL ia AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE GOODLAND KS 856 PM MST THU FEB 17 2000 UPR AIR ANALYSIS...AREA PROFILERS...AND SATL SHOWG 70H CIRCULATION OVR NW CORNER OF KS...AND IS MOVG SLOWLY EWD. AS A RESULT CLASSIC WRAP ARND SIGNATURE PER IR/GLD WSR-88D IS NOW OCCURRING OVR NW HALF OF CWFA. RADAR RETURNS HAVE BEEN GRADUALLY FILLING THE LAST HOUR OR SO AND SNOW BANDS NOT MOVG MUCH ATTM. LAW ENFORCEMENT FROM YUMA CNTY REPORTED 2 INCHES WITH ARND AN INCH ELSEWHERE OVR NW HALF OF CWFA. NEW ETA/NGM TAKE CIRCULATION TO THE EAST-NORTHEAST. LATEST RUC WHICH IS NAILING THE 70H CIRCULATION ECHOES THE ETA/NGM IN ITS MOVEMENT. BASED ON THAT...WRAP ARND SNOW SHOULD START DECREASING AFTER MIDNIGHT IN WRN CWFA...AND BTWN 09Z-12Z IN ERN PORTIONS OF AREA. CONVECTION STARTING UP TO S AND SE OF AREA SHOULD PREVENT SNOWFALL AMOUNTS FROM REACHING ADVISORY CRITERIA. BASED ON WHAT HAVE RECEIVED SO FAR AND WRAP ARND EXPECTED WL UP TO 2-4 IN YUMA CNTY CO...AND 1-3 IN THE NW CORNER OF KS. REST OF AREA IN GOOD SHAPE AS FAR AS AMOUNTS. BASED ON LATEST MDL GUIDANCE WL HAVE WINDS BECMG NORTH IN THE BREEZY CATEGORY INSTEAD OF NE DIR. WL ALSO CLEAN UP SOME WORDG AS WELL. .GLD...NONE. BULLER ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 430 PM EST TUE FEB 8 2000 .SYNOPSIS...FORECAST CONCERN TODAY WILL CONTINUE TO BE WITH SNOW COVERAGE...INTENSITY...AND ACCUMULATIONS. CURRENT SFC ANALYSIS INDICATES A 1004 MB LOW IN CENTRAL OKLAHOMA...MATCHING UP WELL WITH 06HR ETA/NGM/AVN PROGS. ON THE IR/WV SATELLITE LOOPS...DISTINCT W TO E NRN EDGE OF ENHANCED MID AND UPPER LAYER MOISTURE/CLOUDS IS CURRENLY OVER FAR NRN LWR MI...ALONG AXIS OF 500-300 MB JET AND CONFLUENT DEFORMATION. MOSAIC RADARS ACROSS SE WI/SW LOWER MI ARE BEGINNING TO LIGHT UP. NARROW...W-E ORIENTED BANDS OF THE HEAVIER SNOW ON THE NRN EDGE IS INDICATIVE OF THE INCREASING LOW-MID LEVEL FRONTOGENESIS...SIMILAR TO WHAT WAS EXPERIENCED WITH THE EVENT LAST WEEKEND. .MODEL DISCUSSION... 00Z RAOBS INDICATED A STRONG N-S TEMPERATURE GRADIENT AT 850 MB FROM THE SOUTHERN PLAINS NE THROUGH TEH GREAT LAKES REGION...THOUGH NEITHER THE ETA NOR NGM FULLY CAPTURED THE HIGH DEGREE OF BAROCLINICITY IN THE 00Z INITIALIZATION. OVER THE LAST 3 RUNS...EACH SUCCESSIVE ETA RUN HAS SLOWED DOWN PROGRESSION OF 500 MB LOW/VORT LOBE...AND HAS TRACKED THE SFC LOW FARTHER SOUTH. NGM HAS ACTUALLY EXHIBITED BETTER CONSISTENCY WITH 500 MB FEATURES OVER THE PAST 2 RUNS...ALONG WITH ADVERTISING A LOW TRACK FARTHER TO THE SOUTH. .SHORT-TERM FORECAST DISCUSSION... UPPER SHORTWAVE TROUGH WILL UNDERGO A BIT OF SHEARING OVER THE NEXT 24 HRS AS IT ENCOUNTERS A MORE CONFLUENT FLOW PATTERN ALOFT. THIS WILL KEEP THE LOW TRACK S OF LOWER MI (ACROSS THE CENTRAL OH VALLEY LATE TODAY AND OVERNIGHT)...WHILE AT THE SAME TIME WILL TEND TO STRETCH OUT THE COLD CONVEYOR BELT MOISTURE OVER A WIDE AREA FROM W TO E AND CONTINUE WITH THE SHARP MOISTURE DELINEATION FROM S TO N. UPPER JET AXIS OVER NRN LWR MI THIS MORNING WILL SLIDE S/SE THIS AFTERNOON AND OVERNIGHT...WHICH WILL KEEP THE BULK OF RIGHT ENTRANCE REGION JET UPPER DIVERGENCE/ 850-500 MB Q-VECTOR CONVERGENCE OVER SOUTHERN LOWER MI. ANOTHER JET AXIS ROUNDING THE BASE OF THE UPPER TROUGH WILL FURTHER BOOST UVV'S WELL S OF THE REGION...AS IT COUPLES WITH THE RIGHT ENTRANCE FORCING FROM THE NRN JET STREAK. HAVE CONTINUED WITH THE 1-3/2-4 INCH AMOUNTS ACROSS THE FAR SRN PTN OF NRN LWR MI TODAY...WITH LIGHTER AMOUNTS NORTH. LATEST (06Z) RUC 6HR QPF BETWEEN 12Z AND 18Z IS BASICALLY A BLEND OF THE SLIGHTLY WETTER 00Z/06Z ETA AND DRIER 00Z NGM...WHERE ETA DEPICTS ABOUT A QUARTER INCH OF TOTAL LIQUID EQUIVALENT ACROSS THE FAR S/SE COUNTIES IN NRN LWR THROUGH MIDNIGHT. ANY NRN SHIFT OF THE 850/700 MB LOW TRACKS AND (THUS) MOST FAVORABLE 850-700 MB DEFORMATION WOULD INCREASE THESE TOTALS GREATLY...WILL NEED TO MONITOR THIS CLOSELY THROUGH THE DAY. .EXTENDED DISCUSSION... HAVE WORDED CHANCE OF SNOW SHOWERS IN LAKES SUPERIOR/MICHIGAN SNOWBELT IN SAT NIGHT PORTION OF EXTENDED. OTHERWISE...NO OTHER CHANGES MADE. 60 HR AVN SHOWS SECONDARY VORT LOBE DIVING INTO SRN ONTARIO E OF LAKE SUPERIOR SAT NIGHT. DO NOT EXPECT MUCH IN THE WAY OF DYNAMICAL FORCING WITH ERN UPR/NRN LWR MI ON THE BACK SIDE OF CIRCULATION... HOWEVER INCREASING COLD ADVECTION AT LOW LEVELS COULD KICK OF LAKE EFFECT SNOW SHOWERS LEE OF LAKES MI AND SUPERIOR. AVN SHOWS 850 MB TEMPS DROPPING TO AROUND -15C...ONLY MARGINAL INSTABILITY FOR LES THOUGH SUCH TEMP REGIME NEAR CLOUD TOP WOULD FAVOR GOOD DENDRITIC GROWTH AND THUS LARGER SNOWFLAKES. .APX...NONE. HURLEY mi EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 930 PM CST THU FEB 17 2000 THINGS FINALLY STARTING TO GET GOING TONIGHT AS STRONG ELEVATED CONVECTION INCREASES OVER SRN KS AND NRN OK. EXPECT ACTIVITY TO BUILD SOUTHWARD SOME...CLOSER TO HIGHER THETA-E AIR BUT HOW FAR SOUTH REMAINS IN QUESTION. LATEST MESONET SHOWS 320K+ THETA-E IN SW OK...HOWEVER CAP REMAINS STRONG AND MOST OF THE FORCING IS HAPPENING ABOVE THE COOL SFC AIR AS LLJ INCREASES. LATEST RUC SHOWS -6 850MB COMPUTED LI ACROSS NORTHCENTRAL OK. WILL BE ISSING UPDATE SOON TO MENTION SVR IN NRN ZONES WHERE SVR WATCH NUMBER 36 IS IN EFFECT UNTIL 3AM. AGREE WITH REASONING AND LOCATION. WILL HAVE TO SEE HOW FAR SOUTH CONVECTION CAN BUILD. GOING FCST NOT TOO BAD AS FAR AS POPS AND RISING TEMPS TONIGHT. IF ANYTHING...TEMPS WILL RISE QUICKLY AS WARM FRONT LIFTS NORTH. HOW FAST AND HOW FAR FRONT WILL LIFT DEPENDANT ON TRACK OF SFC LOW. LATEST SUBJECTIVE ANALYSIS SHOWS SFC LOW ONLY A LITTLE FURTHER SOUTH THAN 12Z MODEL PROGS. NEW ETA FINALLY COMING IN AND SHOWS ONLY SLIGHT CHANGE TO SFC LOW BUT KEEPS COOL AIR FIRMLY IN PLACE OVER ERN ZONES. MAY TWEAK TEMPS AND POPS SOME. FCSTID = 26 .TUL... AR...NONE. OK...NONE. ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 930 PM EST THU FEB 17 2000 THINGS SEEM TO BE EVOLVING MORE OR LESS AS PLANNED THIS EVENING. 00Z SURFACE ANALYSIS SHOWS INCIPIENT WEDGE OF HIGH PRESSURE E OF THE MOUNTAINS...BUT NOT MUCH OF A PUSH OF DRY AIR FROM THE NE. LOW LEVEL ISENTROPIC LIFT HAS APPARENTLY KICKED IN WITH EXTENSIVE LOW CLOUDINESS AND LIGHT PRECIP DEVELOPING OVER NE GA AND UPSTATE SC. ALTHO THE CURRENT SET OF ZONES IS IN FAIRLY GOOD SHAPE...SOME TWEAKS ARE IN ORDER. THE MAIN CONCERN IS THE POSSIBILITY OF SOME LIGHT FREEZING RAIN AT PRECIP ONSET ACROSS THE NW PIEDMONT. THIS POSSIBILITY SEEMS TO BE GROWING MORE REMOTE AS THE EVENING PROGRESSES. WET BULB TEMPS ARE CURRENTLY IN THE MID 30S ACROSS THE NW PIEDMONT. NEITHER THE 18Z ETA OR THE 00Z RUC SHOW SUB-FREEZING WET BULB TEMPS MAKING IT DOWN TO THE SW OF GSO AT 06Z...WHEN MODELS SHOW THE BEST POTENTIAL FOR FREEZING PRECIP. ETA FORECAST SOUNDING FOR THE NW PIEDMONT AREA NO LONGER SUPPORTS THE IDEA OF FREEZING RAIN. FOR THESE REASONS...WILL REMOVE THIS WORDING FROM THE NW PIEDMONT ZONES. UNLESS A SIGNIFICANT SOUTHWEST PUSH OF DRIER AIR OCCURS CONTRARY TO WHAT THE MODELS INDICATE...LOW TEMPS ARE ALSO A FEW DEGREES TOO COOL...AND WILL CONSIDER BUMPING THEM UP A BIT. AS FOR PRECIP CHANCE...FOR NOW WILL LEAVE IT ALONE. THE REMAINDER OF THE FORECAST...ESPECIALLY FRIDAY...CONTINUES TO LOOK PROBLEMATIC WITH HIGH BUST POTENTIAL. CURRENT SET OF ZONES FAVORS BREAKING OUT OF ANY WEDGE EFFECTS BY DAYS END. SHOULD THAT NOT OCCUR...THEN TEMPS WILL BE MUCH COOLER THAN FORECAST. THE 18Z ETA CONTINUES TO FAVOR THE WARMUP AS FORECAST...BUT CONFIDENCE IS NOT ESPECIALLY HIGH. .GSP...NONE. MOORE sc AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 920 PM CST THU FEB 17 2000 SO FAR...TRENDS EXPECTED BY EARLIER MESO ANALYSIS HOLDING. INCREASING CONVECTIVE PCPN AREA STARTING TO ROB MOISTURE FOR WKNG ISENTROPIC LIFT ACROSS EXTREME SERN SD AND ADJACENT NW IA. BIG ISSUE FOR ANY FURTHER UPDATES IS THE POTENTIAL FOR MODERATE AND HEAVY SNOWS. INCREASING WAA PROFILES SEEN IN PROFILES TO SOUTH OF REGION... HOWEVER...DEFORMATION BAND CONTINUES TO SHOW SIGNS OF SOUTHWARD SAG. RUC HIGHLY SUPPORTIVE OF EARLIER MESOETA FCST...LENDING CREEDENCE TO THAT SLN. UPPR JET IN WDL PROF PULLING AWAY...AND COUPLING OF FEATURE WITH SRN IMPULSE ALSO SHIFTING SLOWLY OUT OF IMMEDIATE AREA BETWEEN 06Z-12Z. WL LOWER NRN TIER OF ADVY ATTM. IF TRENDS CONTINUE AND ARE FURTHER SUPPORTED IN 00Z MDL RUNS...CUD SEE LOWERING OF ADVY AREAS FOR REMAINDER OF CWA ARND MIDNIGHT. COORD WITH KOAX AND KDMX ON LOWERING ADVY AREA. OTHER ISSUES OF TEMPS AND POSSIBLE FOG. FALL IN TMPS SHUD BE CLOSELY TIED TO LOW LVL CAA AS WEALTH OF LOW LVL MOISTURE IN PLACE FOR CLOUDS. MAY BE LOWERING OF STRATUS TO SOME AREAS OF FOG LATER TONIGHT...ESPLY ALG APPARANT MOISTURE DISCONTINUITY ARCING THRU NRN CWA. ADDED IN PATCHY FOG IN THOSE AREAS EARLIER. EXPECT PACKAGE UPDATE AROUND 0330Z. .FSD...SNOW ADVISORY TONIGHT EXTREME NORTHEAST NEBRASKA AND PARTS OF NORTHWEST IOWA. CHAPMAN sd AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA NATIONAL WEATHER SERVICE ABERDEEN SD 915 PM CST THU FEB 17 2000 MAIN CONCERN THIS EVENING DEALS WITH LOW CLOUDS AND FOG POSSIBILITIES. LATEST RUC SHOWS DRY AIR COMING IN AS HIGH PRESSURE DROPS OVER THE CWA. HOWEVER...RUC FORECASTED SOUNDINGS SHOW THAT VERY LOWEST LAYERS(900MB TO SURFACE) REMAIN NEARLY SATURATED AS INVERSION SETS UP. 00Z KABR SOUNDING WOULD SUPPORT THIS AS WELL. WITH WINDS IN LOWEST LAYERS ALSO LIGHT TO CALM...NOT MUCH OF A CHANCE FOR HIGH MOISTURE TO MIX OUT. LATEST LAMP GUIDANCE SUGGESTS THAT LOW CLOUDS WILL HANG OVER ALL OF CWA THROUGH NIGHT...WITH PATCHY FOG POSSIBLE. WITH THE CLOUDS...OVERNIGHT LOWS WILL ALSO STAY UP A BIT. WILL NEATEN UP CLOUD COVER...ADD PATCHY FOG AND BUMP UP LOWS 3 TO 5 DEGREES ALL PLACES. UPDATED ZONES OUT SHORTLY. .ABR...NONE. HINTZ sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE COLUMBIA SC 957 AM EST FRI FEB 18 2000 DISC: 14Z SFC ANALYSIS SHOWS HI PRES CONT TO WEDGE SWD ACRS THE STATE. TROF/CSTL FRONT JUST OFF THE CST. SATELLITES SHOWS LOTS OF CLDS ACRS THE STATE THIS MORNING. ALTHOUGH...SOME SUN ALNG THE S CSTL AREAS. 00Z MODELS AND MORNING RUC INDICATE THAT WEDGE WL BREAK DOWN DURING THE AFT. HOWEVER...THE USUAL TREND IS TO BRING WINDS ARND FROM NE TO SE/S TO QUICKLY. ETA MODEL LIS SHOW WEDGE OF STABLE AIR CONT ACRS MUCH OF THE AREA...BUT SLOWLY ERODES FM THE SE DURING THE AFT/EARLY EVENING. VWP SHOWING THE LAYER OF COLD AIR VERY THIN...LESS THAN 1000 FT. TEMP CURRENTLY RUNNING FM THE MID/UPR 30S N TO AROUND 50 S. WITH AFT PACKAGE...WL SLOW DOWN THE TREND TWRD BREAKDOWN OF WEDGE AND ADJUST TEMPS DOWNWARD IN MOST AREAS...ESP N AND W. WITH SOME CLRNG SKIES TRYING TO PUSH WWD ACRS THE SRN PTN OF THE STATE...WL BE THE MOST OPTIMISTIC THERE WITH AFT TEMPS. WL CONT WITH SOME SML CHC FOR -RA/-SHRA DURING THE AFT. ALTHOUGH MOISTURE CONT TO THIN...ESP OVR THE SERN AREAS...SOME WK ISENTROPIC LIFT STILL OCCURING ACRS THE AREA. .CAE...NONE. LCV sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LITTLE ROCK AR 315 PM CST FRI FEB 18 2000 COLD FRONT MOVING PER RUC AND SHOULD BE OUT OF AR BY 01Z. LOW COLD AIR STRATUS WILL LINGER IN THE NORTH EARLY TONIGHT BUT WILL BE CLEARING OUT LATER WITH FREEZING TEMPERATURES. SEVERE WEATHER THIS AFTERNOON FROM A COUPLE OF SUPERCELLS WITH AT LEAST ONE TORNADO MOVING BETWEEN CENTRAL AND EASTERN ARKANSAS. ALL SEVERE WEATHER SHOULD BE OUT OF LIT CWA BY 430 PM CST. MOS TEMPS HAVE BEEN GOOD ON THIS SYSTEM SO WILL NOT VARY FROM IT TONIGHT. .LIT...NONE ar AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE CHICAGO IL 1020 AM CST FRI FEB 18 2000 WELL DEVELOPED "WRAPAROUND" PRECIP PRODUCING MODERATE/HEAVY SNOW AND INCREASING OVER SOUTHEAST IOWA. THIS SEEMS TO CONFIRM RUC/ETA/NGM SHORT TERM FORECASTS BRINGING VERTICAL MOTION BULLSEYE WITH SIMILAR CONDITIONS ACROSS NORTHERN AND CENTRAL PORTIONS OF OUR AREA DURING THE AFTERNOON. WOULD EXPECT THIS TO PRODUCE ADDITIONAL 3-4 INCH ACCUMULATIONS MANY AREAS...WHICH MEANS EARLIER FORECAST TOTALS ARE PRETTY MUCH ON TRACK. PLAN SOME CLEANUP TO WORDING AT 11 A.M. KAPLAN il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 230 PM EST FRI FEB 18 2000 KIWX RADAR SHOWING MOST OF THE PRECIP HAS MOVED OUT OF THE AREA FOR THE MOMENT. KLOT RADAR SHOWING WRAP AROUND SNOW FILLING IN OVER N IL/E IA. MAIN FCST CONCERN WILL BE ADDITIONAL SNOWFALL IN NORTH THIS EVENING. ALL MODELS INDICATE DECENT AREA OF UVV COMING THRU NW CWA THIS EVENING IN AREA OF FAVORABLE WRAP AROUND MOISTURE. 18Z RUC HAS 500MB SHORT WAVE OVER C IL WITH LEFT FRONT EXIT REGION OF UPPER JET OVER N IN. THEREFORE EXPECTING AN ADDITIONAL 1 TO 3 INCHES OF SNOW OVER NW CWA. ATTM LEANING TOWARD CONTINUING WARNING IN THIS AREA THRU 02Z. WRAP AROUND MOISTURE TO HANG OVER E/SE CWA THRU 12Z SAT BUT MAIN AREA OF LIFT TO MOVE OFF E/NE AFTER 03Z. DRY FCST IN STORE REMAINDER OF PERIOD AS HIGH PRESSURE BUILDS INTO SOUTHERN PLAINS WITH RIDGE EXTENDING UP INTO GREAT LAKES REGION. WEAK TROF SWINGS THRU NORTHERN GREAT LAKES SAT NITE BRINGING JUST SOME CLOUDS INTO NORTHERN CWA. HIGH PRESSURE GRADUALLY SLIDES EAST INTO OHIO VALLEY SUN AND MON KEEPING DRY WX AND SEASONABLE TEMPS OVER THE AREA THRU THE WEEKEND. EXTENDED HAS NEXT SYSTEM DIGGING INTO THE PLAINS TUE AND WED. WARM FRONT ASSOC WITH IT WILL MOVE UP TOWARD THE AREA BRINGING AN INC IN TEMPS AND A CHANCE FOR RAIN. GOING FCST HAS THIS INDICATED AND WILL CONTINUE THIS TREND INTO WED. FWC/FAN GUIDANCE IN NEAR TERM CLOSE AND REASONABLE. .IWX...WINTER STORM WARNING THIS EVENING MIZ077>079 INZ003>005. JAL in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1130 AM EST FRI FEB 18 2000 LETTING CURRENT FORECAST RIDE WITH ONLY MINIMAL CHANGES MADE...MAINLY TO LOWER SNOWFALL TOTALS BUT STILL AT OR ABOVE WARNING CRITERIA. STILL ANTICIPATING THE LOW PRESSURE CENTER TO TRACK SOUTH OF MICHIGAN THROUGH THE OHIO RIVER VALLEY. WITH LOW CENTER PROGRESSION...LATEST RUC SOUNDINGS AND CRITICAL THICKNESS VALUES REVEALING COLD ENOUGH TEMPS TO PULL ANY MENTION OF MIX PCPN FROM SOUTHERN COUNTIES. FEEL BEST CHANCE OF MIX PCPN WILL BE SOUTH OF GRR CWA. SNOWFLAKE SIZE AND GUSTY WINDS HAS HELPED TO PROHIBIT ANTICIPATED SNOW ACCUMULATION FOR THIS TIME FRAME...HOWEVER WITH TEMPS EXPECTED TO RISE TO AROUND 30 A WETTER SNOW WOULD HELP ACCUMULATION AMOUNTS. LATEST RUC 295K ISENTROPIC ANALYSIS SUGGESTS SNOW WILL CONTINUE THROUGH THIS AFTERNOON AND END LATER THIS EVENING. MIXING RATIOS OF AT LEAST 3 TO 4 G/KG OVER SRN CWA WITH A TOTAL TIME FRAME JUST UNDER 12 HOURS WOULD SUPPORT AT LEAST 6 INCHES OF TOTAL ACCUMULATION BY THIS EVENING. LOOKING UPSTREAM AT OBSERVATIONS UNDER THE APPROACHING DEFORMATION ZONE SNOWFALL RATES CONTINUE STRONG AND SHOULD REMAIN STRONG AS THIS SLIDES INTO WEST MICHIGAN THIS AFTERNOON. LATEST VIS SAT IMAGERY ALSO SHOWS A CONVECTIVE LOOKING AREA OF PCPN MOVING INTO NORTHERN IL WHICH WILL CONTINUE A NORTHEAST TRACK INTO WEST MICHIGAN AND HELP INCREASE SNOWFALL RATES. DISTANCE SPEED CALCULATIONS PUT THIS AREA INTO GRR CWA JUST AFTER 19Z. NORTHERN SECTIONS OF CWA WILL HAVE A HARDER TIME REACHING ADVISORY/WARNING CRITERIA BY THE TIME THE SNOWFALL STOPS THIS EVENING...HOWEVER WITH A SLOW MOVEMENT AND WHAT IS UPSTREAM DECIDED TO LEAVE FORECAST AS IS. MCINERNEY .GRR...WINTER STORM WARNING. ..OCEANA...NEWAYGO...MECOSTA...ISABELLA COUNTIES ON SOUTH THROUGH THIS EVENING. SNOW ADVISORY FOR MASON...LAKE...OSCEOLA...AND CLARE THROUGH THIS EVENING. mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH, NC 1030 AM EST FRI FEB 18 2000 RAIN HAS JUST ABOUT ENDED BUT EXPECT OCCASIONAL DRIZZLE IN THE STABLE POOL WHICH WAS ABOUT 3KFT THICK AT GSO AND 1-2KFT THICK HERE ACCORDING TO VAD WINDS. JOY...JOY...ALL SET UP FOR A POTENTIAL TEMP BUST AS ALL MODEL INDICATORS...INCLUDING 14Z RUC SHOW SIGNIFICANT EROSION BY 18Z AND WAA KICKING TEMPS INTO THE 50S AND LOWER 60S. CURRENT FCST IS MIDDLE OF THE ROAD...WHICH WILL PAN OUT NICELY IF WEDGE HOLDS ON A FEW ADDITIONAL HOURS. THIS SEEMS QUITE REASONABLE AND DOUBT THAT I MAKE ANY SIGNIFICANT CHANGES ALTHOUGH I MAY LOWER THE MAXES IN THE NW PIEDMONT DUE TO THE THICKNESS OF THE COOL POOL. .RAH...NONE. MLM nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CLEVELAND OH 255 PM EST FRI FEB 18 2000 BEST UVV AND MOISTURE FOCUSED ALG WRMFNT ACRS S OH. LOW TO PASS ACRS S OH THIS EVENING AND SW/V PROGGED OVHD JUST AFT 06Z. CONVECTION ACRS S OH WL BLOCK BEST MOISTURE BUT AS SW/V AND LOW GET CLOSER PCPN WL EXPAND AGAIN LATE THIS AFTERNOON AND EVENING. SFC WND HAS COME NE ALREADY BUT RUC SHOWS WARMING ALOFT TO MAX OUT BETWEEN 00Z-03Z. HARD TO PIN DOWN WHERE SFC FREEZING LINE WL FLUCTUATE TO. WITH SFC FLOW FM NE TEMPS SHUD BEGIN TO COME DOWN BY SUNSET. WITH LIMITED QPF WARNINGS ARE NO LONGER NECESSARY BUT WL POST WINTER WEATHER ADVISORY FOR COUNTIES CURRENTLY AT FREEZING AND THEN ONE TIER SOUTH TO MFD AND CAK AND WARREN ALLOWING FOR SOME COOLING EARLY TNGT. PCPN SHUD STAY LGT SNOW TOL AREA AND WL NOT REQUIRE AN ADVISORY SINCE ONLY AN INCH OR TWO LIKELY TONIGHT. CHANGE BACK TO SNOW ENTIRE FCST AREA FM NW TO SE 02Z-08Z. WRAP AROUND CLOUDS/FLURRIES OR LGT SNOW INTO SAT. SECOND COLD FNT DROPPING S ACRS GRTLKS BY SUN MORN. H8 TEMPS NOT COLD ENUF FOR LAKE EFFECT SNOW AND NOT MUCH MOISTURE AVAILABLE BUT INVERSION PROGGED TO SET UP AROUND 850 MB AND SOME SC AND FLURRIES MAINLY NE OH AND NW PA. .CLE...WINTER WEATHER ADVISORY N 1/4 OH AND NW PA TNGT KOSARIK oh