Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/29/15


AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
437 AM PDT TUE OCT 27 2015 .SYNOPSIS...MOSTLY CLOUDY SKIES TODAY AHEAD OF AN INCOMING WEATHER SYSTEM THAT MAY PRODUCE A FEW SHOWERS OR LIGHT SPRINKLES OVER THE NORTH BAY THIS AFTERNOON. LIGHT RAIN CHANCES INCREASE OVERNIGHT INTO WEDNESDAY MORNING AS THE MAIN COLD FRONT WILL PASS THROUGH THE STATE WITH THE BEST CHANCE OF RAIN FOR THE NORTH BAY. MORNING LIGHT RAIN TURNS TO SHOWERS BY WEDNESDAY AFTERNOON BEFORE ENDING. HIGH PRESSURE BUILDS THURSDAY THROUGH HALLOWEEN WITH DRY AND MILD WEATHER ALONG WITH SOME BREEZY NORTH WINDS IN THE HILLS. A COLDER TROUGH MAY ARRIVE FROM THE NORTH BY SUNDAY OR MONDAY WITH THE NEXT CHANCE OF RAIN. && .DISCUSSION...AS OF 4:04 AM PDT TUESDAY...LOTS OF HIGH CLOUDS OVER THE REGION THIS MORNING AHEAD OF THE FRONTAL BOUNDARY OVER THE EASTERN PACIFIC. THERE WAS SOME MORE WIDESPREAD DENSE FOG BEFORE MIDNIGHT BUT THE CLOUD COVER HAS SHUT DOWN THE RADIATIONAL FOG WITH ONLY WATSONVILLE CURRENTLY REPORTING 1/4 MILE. THE HRRR AND RAP MODELS SHOW A FEW SCOUT SHOWERS TODAY IN THE NORTH BAY BUT EXPECTING ONLY TRACE AMOUNTS WITH ISOLATED SHOWERS/SPRINKLES. SKIES STAY CLOUDY TODAY THROUGH TONIGHT WITH HIGHS STILL IN THE 70S FOR MOST OF THE DISTRICT. LONG TALKED ABOUT FRONTAL BOUNDARY WILL FINALLY ARRIVE LATE TONIGHT INTO WEDS MORNING. IN GENERAL RAIN TOTALS HAVE BACKED OFF WITH THE BEST CHANCES APPEARING TO BE FOR THE NORTH BAY WEDS MORNING WHEN 0.10-0.25 IS POSSIBLE. THERE`S NO COLD ADVECTION OR GOOD FORCING WITH MAIN JET ENERGY STAYING TO OUR NORTH. SOME HIT AND MISS SHOWERS ALSO FORECAST OVER THE GREATER BAY AREA AND DOWN TO AROUND MONTEREY BAY ON WEDS BUT IN GENERAL RAINFALL IS LOOKING LIGHT AND SPORADIC WITH AREAS SOUTH OF SALINAS EXPECTED TO RECEIVE LITTLE OR NO RAINFALL. ANY SHOWERS WILL QUICKLY END BY WEDS EVENING. HIGH PRESSURE WILL QUICKLY REBUILD ON THURSDAY WITH DRY AND MILD WEATHER RETURNING. OFFSHORE PRESSURE GRADIENTS WILL SET UP WITH SOME MODERATE NORTHEAST WINDS DEVELOPING ACROSS THE BAY AREA HILLS. IF THE MIDWEEK RAINS DONT DEVELOP AS EXPECTED FIRE WEATHER CONCERNS WILL MAY BECOME FRONT AND CENTER WITH A FAIRLY CLASSIC FALL OFFSHORE WIND PATTERN IN PLACE AS THE THERMAL TROUGH STRADDLES THE COAST. THE GRADIENT RELAXES LATER FRIDAY INTO SATURDAY BUT EXPECT CLEAR SKIES AND SEASONABLY WARM WEATHER FROM THE 70S TO MID 80S WITH DOWNSLOPE WARMING OFF THE HILLS. MODELS BEING CONSISTENT IN SHOWING A COLD TROUGH FROM THE NORTH BY NEXT SUNDAY INTO MONDAY WITH COOLER TEMPERATURES AND A CHANCE OF RAIN. && .AVIATION...AS OF 4:30 AM PDT TUESDAY...DRIER AIR OVER THE SFO BAY AREA THIS MORNING WITH RH AS MUCH AS 20-30% LOWER THAN YESTERDAY MORNING. PATCHY CIGS IN THE MRY BAY AREA MAINLY AROUND SNS SHOULD CLEAR EARLY. VICINITY OF KSFO...VFR. WEST WINDS GUSTING TO 18 KT AFTER 20Z. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...AREAS OF LIFR CONDITIONS WITH VSBYS AS LOW AS 2-3 MILES THROUGH 15Z. && .MARINE...AS OF 03:07 AM PDT TUESDAY...A WEAK UPPER LEVEL TROUGH WILL MOVE THROUGH THE AREA WEDNESDAY THEN DEEPEN OVER THE WESTERN INTERIOR. AS A RESULT NORTHWEST WINDS WILL INCREASE THURSDAY THROUGH FRIDAY. WINDS WILL DECREASE THIS WEEKEND AS THE TROUGH MOVES EAST. A LONG PERIOD SWELL WILL MOVE INTO THE AREA WEDNESDAY AND CONTINUE THROUGH THURSDAY. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...NONE. && $$ PUBLIC FORECAST: RWW AVIATION: W PI MARINE: W PI VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK AND TWITTER AT: WWW.FACEBOOK.COM/NWSBAYAREA WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
404 AM PDT TUE OCT 27 2015 .SYNOPSIS...MOSTLY CLOUDY SKIES TODAY AHEAD OF AN INCOMING WEATHER SYSTEM THAT MAY PRODUCE A FEW SHOWERS OR LIGHT SPRINKLES OVER THE NORTH BAY THIS AFTERNOON. LIGHT RAIN CHANCES INCREASE OVERNIGHT INTO WEDNESDAY MORNING AS THE MAIN COLD FRONT WILL PASS THROUGH THE STATE WITH THE BEST CHANCE OF RAIN FOR THE NORTH BAY. MORNING LIGHT RAIN TURNS TO SHOWERS BY WEDNESDAY AFTERNOON BEFORE ENDING. HIGH PRESSURE BUILDS THURSDAY THROUGH HALLOWEEN WITH DRY AND MILD WEATHER ALONG WITH SOME BREEZY NORTH WINDS IN THE HILLS. A COLDER TROUGH MAY ARRIVE FROM THE NORTH BY SUNDAY OR MONDAY WITH THE NEXT CHANCE OF RAIN. && .DISCUSSION...AS OF 4:04 AM PDT TUESDAY...LOTS OF HIGH CLOUDS OVER THE REGION THIS MORNING AHEAD OF THE FRONTAL BOUNDARY OVER THE EASTERN PACIFIC. THERE WAS SOME MORE WIDESPREAD DENSE FOG BEFORE MIDNIGHT BUT THE CLOUD COVER HAS SHUT DOWN THE RADIATIONAL FOG WITH ONLY WATSONVILLE CURRENTLY REPORTING 1/4 MILE. THE HRRR AND RAP MODELS SHOW A FEW SCOUT SHOWERS TODAY IN THE NORTH BAY BUT EXPECTING ONLY TRACE AMOUNTS WITH ISOLATED SHOWERS/SPRINKLES. SKIES STAY CLOUDY TODAY THROUGH TONIGHT WITH HIGHS STILL IN THE 70S FOR MOST OF THE DISTRICT. LONG TALKED ABOUT FRONTAL BOUNDARY WILL FINALLY ARRIVE LATE TONIGHT INTO WEDS MORNING. IN GENERAL RAIN TOTALS HAVE BACKED OFF WITH THE BEST CHANCES APPEARING TO BE FOR THE NORTH BAY WEDS MORNING WHEN 0.10-0.25 IS POSSIBLE. THERE`S NO COLD ADVECTION OR GOOD FORCING WITH MAIN JET ENERGY STAYING TO OUR NORTH. SOME HIT AND MISS SHOWERS ALSO FORECAST OVER THE GREATER BAY AREA AND DOWN TO AROUND MONTEREY BAY ON WEDS BUT IN GENERAL RAINFALL IS LOOKING LIGHT AND SPORADIC WITH AREAS SOUTH OF SALINAS EXPECTED TO RECEIVE LITTLE OR NO RAINFALL. ANY SHOWERS WILL QUICKLY END BY WEDS EVENING. HIGH PRESSURE WILL QUICKLY REBUILD ON THURSDAY WITH DRY AND MILD WEATHER RETURNING. OFFSHORE PRESSURE GRADIENTS WILL SET UP WITH SOME MODERATE NORTHEAST WINDS DEVELOPING ACROSS THE BAY AREA HILLS. IF THE MIDWEEK RAINS DONT DEVELOP AS EXPECTED FIRE WEATHER CONCERNS WILL MAY BECOME FRONT AND CENTER WITH A FAIRLY CLASSIC FALL OFFSHORE WIND PATTERN IN PLACE AS THE THERMAL TROUGH STRADDLES THE COAST. THE GRADIENT RELAXES LATER FRIDAY INTO SATURDAY BUT EXPECT CLEAR SKIES AND SEASONABLY WARM WEATHER FROM THE 70S TO MID 80S WITH DOWNSLOPE WARMING OFF THE HILLS. MODELS BEING CONSISTENT IN SHOWING A COLD TROUGH FROM THE NORTH BY NEXT SUNDAY INTO MONDAY WITH COOLER TEMPERATURES AND A CHANCE OF RAIN. && .AVIATION...AS OF 10:25 PM PDT MONDAY...TRICKY FORECAST WITH LOW CLOUDS INCREASING ACROSS THE AREA WHILE HIGH CLOUDS MOVE OVERHEAD IN ADVANCE OF AN APPROACHING SYSTEM. WILL GO MODERATELY PESSIMISTIC BASED ON CURRENT SURFACE REPORTS. BURN-OFF SLATED FOR AFTER 16Z. WINDS SHOULD NOT BE A FACTOR AND WILL MOSTLY STAY UNDER 10 KT BY 07Z AND CONTINUE THROUGH TUESDAY MORNING. LOW CONFIDENCE. VICINITY OF KSFO...LOW CLOUDS ONLY FORECAST TO DROP SFO DOWN TO MVFR CONDITIONS OVERNIGHT WITH CIGS AROUND 015. WINDS WILL DROP TO UNDER 10 KT AFTER 07Z. VFR RETURNS AFTER 17Z. LOW TO MODERATE CONFIDENCE. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...VLIFR TO LIFR CONDITIONS OVERNIGHT WITH CIGS DOWN TO 002 AND VIS OF POTENTIALLY LESS THAN 1/2 SM. WINDS UNDER 10 KT THROUGH TUESDAY MORNING. LOW CONFIDENCE. && .MARINE...AS OF 03:07 AM PDT TUESDAY...A WEAK UPPER LEVEL TROUGH WILL MOVE THROUGH THE AREA WEDNESDAY THEN DEEPEN OVER THE WESTERN INTERIOR. AS A RESULT NORTHWEST WINDS WILL INCREASE THURSDAY THROUGH FRIDAY. WINDS WILL DECREASE THIS WEEKEND AS THE TROUGH MOVES EAST. A LONG PERIOD SWELL WILL MOVE INTO THE AREA WEDNESDAY AND CONTINUE THROUGH THURSDAY. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...NONE. && $$ PUBLIC FORECAST: RWW AVIATION: W PI MARINE: W PI VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK AND TWITTER AT: WWW.FACEBOOK.COM/NWSBAYAREA WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1024 PM PDT MON OCT 26 2015 .SYNOPSIS...MILD TEMPERATURES AND DRY WEATHER CONDITIONS WILL PERSIST THROUGH MUCH OF TUESDAY. A PACIFIC SYSTEM WILL THEN BRING A FRONTAL BOUNDARY ACROSS THE REGION LATE TUESDAY INTO WEDNESDAY AND RESULT IN INCREASED CHANCES FOR PRECIPITATION. IN WAKE OF THE SYSTEM...COOLER TEMPERATURES AND BREEZY NORTHERLY WINDS ARE FORECAST THURSDAY AND FRIDAY. && .DISCUSSION...AS OF 8:44 PM PDT MONDAY...SATELLITE IMAGERY SHOWS A LARGE SWATH OF HIGH CLOUDS MOVING OUT AHEAD OF THE COLD FRONT THAT IS CURRENTLY STRETCHED ACROSS THE EASTERN PACIFIC. HIGH CLOUDS STREAMING ACROSS THE FORECAST AREA ARE MAKING IT HARD TO SEE WHAT IS GOING ON AT THE SURFACE. HOWEVER OBSERVATIONS ALONG THE COAST REVEAL LOW CLOUDS PERSIST UNDER A SHALLOW 800 FOOT MARINE LAYER PER THE FORT ORD PROFILER. THE BLANKET OF HIGH CLOUDS ADVECTING OVER THE REGION WILL HAMPER FURTHER DEVELOPMENT OF LOW CLOUDS OVERNIGHT AND THEREFORE KEEP THE LOW CLOUDS CONFINED PRIMARILY TO THE COAST AND LOCALLY INTO COASTAL VALLEYS AND BAYS. COOL OVERNIGHT LOWS ARE EXPECTED ONCE AGAIN WITH TEMPS DIPPING DOWN INTO THE MID 40S TO MID 50S IN MOST LOCATIONS. A GRADUAL COOLING TREND IS FORECAST THROUGH MIDWEEK AS THE COLD FRONT MENTIONED ABOVE MOVES ACROSS THE REGION. MODELS AGREE THAT THE APPROACHING FRONT WILL SPREAD PRECIP ACROSS THE DISTRICT...HOWEVER DISCREPANCIES REMAIN IN THE TIMING AND INTENSITY OF THE PRECIPITATION. THE EURO HAS THE WETTEST AND FASTEST SOLUTION WHILE THE GFS LAGS ONLY SLIGHTLY BEHIND. THE 12Z EURO BRINGS LIGHT PRECIP TO THE NORTH BAY AS EARLY AS 18Z ON TUESDAY. WHILE THIS SEEMS EARLY THE LATEST RUN OF THE HRRR SHOWS LIGHT SHOWERS ACROSS THE NORTHERNMOST PORTION OF SONOMA COUNTY AROUND 16Z TUESDAY. THE EURO SPREADS SHOWERS SOUTHWARD TOWARD THE SAN FRANCISCO BAY BY 00Z WEDNESDAY WITH THE BULK OF THE PRECIP REACHING THE NORTH BAY AROUND 06Z WEDNESDAY. THE GFS SHOWS A FEW SHOWERS TUESDAY EVENING HOWEVER THE MAIN BAND OF PRECIP DOESN`T REACH THE NORTH BAY TIL WELL AFTER 12Z WEDNESDAY. THE CURRENT FORECAST BRINGS IN A CHANCE OF RAIN TO THE NORTH BAY TUESDAY AFTERNOON WITH CHANCES INCREASING AND SPREADING SOUTH TUESDAY EVENING INTO WEDNESDAY. THIS SOLUTIONS SPLITS THE DIFFERENCE AND IS REASONABLE AT THIS TIME. WILL NOT BE MAKING ANY SIGNIFICANT CHANGES TO THE FORECAST PACKAGE. FROM PREVIOUS DISCUSSION...LIGHT RAIN IS FORECAST TO SPREAD OVER THE SAN FRANCISCO BAY AREA LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. WHILE THE PWAT VALUES ARE FORECAST TO PEAK BETWEEN 1.10" AND 1.30" OVER THE REGION...THE AVAILABLE MOISTURE WILL BE MORE LIMITED OVER THE CENTRAL COAST AS THE BOUNDARY PUSHES THROUGH WEDNESDAY MORNING. HAVING SAID THAT...DO EXPECT MOST LOCATIONS WILL RECEIVE SOME RAINFALL FROM THIS SYSTEM. THE GREATEST RAINFALL AMOUNTS FROM TOMORROW NIGHT INTO WEDNESDAY WILL BE OVER THE NORTH BAY WHERE COASTAL RANGES COULD PICK UP BETWEEN 0.25" TO 0.50" FROM THIS SYSTEM. THE REST OF THE BAY AREA COULD PICK UP BETWEEN 0.10" TO 0.25" WITH GENERALLY LESS THAN 0.10" FURTHER SOUTH. AS TYPICAL WITH THESE SYSTEMS...OTHER COASTAL RANGES FROM THE SANTA CRUZ MOUNTAINS SOUTHWARD COULD PICK UP 0.25" IN ISOLATED LOCATIONS. ONCE THE MAIN TROUGH SHIFTS INLAND WEDNESDAY AFTERNOON...LINGERING SHOWERS WILL BE POSSIBLE INTO THE LATE AFTERNOON AS THE UPPER LEVEL JET DEVELOPS ALOFT. BY LATE WEDNESDAY NIGHT...MUCH OF THE MOISTURE AND UPPER LEVEL SUPPORT WILL BE FAR ENOUGH INLAND TO BRING AN END TO PRECIPITATION OVER THE REGION. AS THE MAIN MID/UPPER LEVEL TROUGH SHIFTS INLAND AND DIVES INTO THE FOUR CORNERS REGION THURSDAY INTO FRIDAY...THE SURFACE PRESSURE GRADIENT WILL TIGHTEN OVER THE AREA AND RESULT IN BREEZY TO WINDY CONDITIONS. THE STRONGEST WINDS WILL BE IN THE HIGHER ELEVATIONS WITH GUSTS TO 40 MPH POSSIBLE...WITH GUSTS TO 30 MPH EXPECTED REGION- WIDE. WIND SPEEDS WILL THEN RELAX LATE FRIDAY INTO SATURDAY AS HIGH PRESSURE BUILDS OVER THE REGION. IN ADDITION...THIS WILL ALLOW FOR A SLIGHT WARMING TREND THROUGH SATURDAY. THE MEDIUM RANGE MODELS CONTINUE TO SHOW SIGNS OF ANOTHER WEATHER SYSTEM DROPPING DOWN ACROSS OUR REGION THIS UPCOMING SUNDAY INTO NEXT MONDAY. && .AVIATION...AS OF 10:25 PM PDT MONDAY...TRICKY FORECAST WITH LOW CLOUDS INCREASING ACROSS THE AREA WHILE HIGH CLOUDS MOVE OVERHEAD IN ADVANCE OF AN APPROACHING SYSTEM. WILL GO MODERATELY PESSIMISTIC BASED ON CURRENT SURFACE REPORTS. BURN-OFF SLATED FOR AFTER 16Z. WINDS SHOULD NOT BE A FACTOR AND WILL MOSTLY STAY UNDER 10 KT BY 07Z AND CONTINUE THROUGH TUESDAY MORNING. LOW CONFIDENCE. VICINITY OF KSFO...LOW CLOUDS ONLY FORECAST TO DROP SFO DOWN TO MVFR CONDITIONS OVERNIGHT WITH CIGS AROUND 015. WINDS WILL DROP TO UNDER 10 KT AFTER 07Z. VFR RETURNS AFTER 17Z. LOW TO MODERATE CONFIDENCE. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...VLIFR TO LIFR CONDITIONS OVERNIGHT WITH CIGS DOWN TO 002 AND VIS OF POTENTIALLY LESS THAN 1/2 SM. WINDS UNDER 10 KT THROUGH TUESDAY MORNING. LOW CONFIDENCE. && .MARINE...AS OF 8:41 PM PDT MONDAY...NORTHWESTERLY WINDS WILL PREVAIL INTO TUESDAY AFTERNOON WITH HIGHER GUSTS LIKELY UNTIL MIDNIGHT. WINDS WILL BECOME SOUTHERLY FOR A SHORT PERIOD OF TIME TUESDAY EVENING AHEAD OF AN APPROACHING STORM SYSTEM. THE FIRST WINTER SWELL OF THE SEASON IS EXPECTED TO ARRIVE ON WEDNESDAY WITH A SWELL OF 18 TO 20 SECONDS. PLEASE BE PREPARED FOR ROUGH CONDITIONS ACROSS THE SAN FRANCISCO AND BREAKING WAVES NEAR OFFSHORE REEFS AND SAND BARS. NORTHERLY WINDS ARE EXPECTED TO STRENGTHEN THURSDAY AS COOL AIR FILTERS IN BEHIND THE DEPARTING STORM SYSTEM. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...NONE. $$ PUBLIC FORECAST: CW AVIATION: BELL MARINE: BELL VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK AND TWITTER AT: WWW.FACEBOOK.COM/NWSBAYAREA WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
808 PM MDT WED OCT 28 2015 .UPDATE... ISSUED AT 800 PM MDT WED OCT 28 2015 HIGHER LEVEL COUDS HAVE OVERSPREAD THE AREA AND WILL CONTINUE OVERNIGHT. THIS COULD HAVE SOME AFFECTS ON LOW TEMPS AND FREEZE WARNING IF THESE CLOUDS LINGER ALL NIGHT OVER NERN CO. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 300 PM MDT WED OCT 28 2015 HIGH CLOUDS ARE INCREASING IN THE WESTERLY FLOW ALOFT ACROSS THE STATE. THE FLOW WILL BECOME SOUTHWEST THURSDAY AS THE CURRENT UPPER RIDGE PUSHES EAST OVER THE GREAT PLAINS. WESTERLY SURFACE WINDS ARE INCREASING AS A SURFACE LOW DEEPENS OVER THE EASTERN PLAINS AHEAD OF AN APPROACHING DRY COLD FRONT. THE COLD FRONT WILL PUSH IN THIS EVENING WITH ONLY A WIND DIRECTION CHANGE...NO PRECIPITATION IS EXPECTED. HIGH CLOUDS WILL THIN AS YOU HEAD NORTHEAST TOWARD NEBRASKA. COLDER TEMPERATURES AND CLEAR SKIES OVER THE FAR NORTHEAST PLAINS WILL ALLOW MINIMUM TEMPERATURES TO FALL BELOW FREEZING...LIKELY INTO THE MID TO UPPER 20S. WILL ISSUE A FREEZE WARNING FOR LOGAN...WASHINGTON...SEDGWICK AND PHILLIPS COUNTIES AS THEY HAVE YET TO EXPERIENCE A HARD FREEZE YET. EXPECT A SLIGHTLY COOLER DAY TOMORROW UNDER MOSTLY CLOUDY SKIES. A WEATHER SYSTEM OVER THE GREAT BASIN DIGGING INTO ARIZONA WILL PUSH ISOLATED TO SCATTERED RAIN AND SNOW SHOWERS OVER THE MOUNTAINS IN THE AFTERNOON. LITTLE TO NO ACCUMULATION IS EXPECTED. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 300 PM MDT WED OCT 28 2015 UPPER LEVEL LOW WILL CONTINUE TO DROP EAST/SOUTHEAST ACROSS THE SOUTHERN U.S. BORDER AREA THURSDAY NIGHT AND FRIDAY. AS A RESULT...THE MAIN LIFT AND WIDESPREAD PRECIPITATION SHIELD ASSOCIATED WITH THE TROUGH WILL ALSO STAY TO OUR SOUTH. WE WILL STILL HAVE A CHANCE OF SHOWERS...BUT THE HIGHEST POPS WILL BE CONFINED TO THE MOUNTAINS FOR MOST OF THIS PERIOD. GENERALLY LIGHT SNOW ACCUMULATIONS IN THE 1 TO 3 INCH RANGE CAN BE EXPECTED THURSDAY NIGHT INTO FRIDAY. OVER THE PLAINS...THE LOW LEVELS ARE RELATIVELY DRY AND THE FRONT ON FRIDAY WILL BRING A MAINLY NORTHERLY WIND COMPONENT. THIS WOULD FAVOR MOST SHOWER DEVELOPMENT TO OCCUR FROM THE PALMER DIVIDE EAST AND SOUTHEAST INTO EAST CENTRAL AND SOUTHEAST COLORADO. THERE IS ALSO SOME MID LEVEL CONVERGENCE/FRONTOGENESIS ALSO NOTED IN THAT REGION. DRIER WEATHER WILL QUICKLY DEVELOP FRIDAY EVENING WITH LARGE SCALE SUBSIDENCE AND CLEARING. ANOTHER FROSTY NIGHT IS EXPECTED AS SKIES CLEAR AND WINDS DIMINISH. FOR HALLOWEEN ON SATURDAY...EXPECT A RETURN TO JUST ABOVE NORMAL TEMPERATURES WITH DOWNSLOPE FLOW...SUBSIDENCE...AND WARM ADVECTION ALOFT. THIS WILL ALSO LIKELY BRING BREEZY CONDITIONS TO LOCATIONS IN/NEAR THE FOOTHILLS...AND DECENT MOUNTAIN TOP STABLE LAYER NOTED SO HAVE INCREASED WINDS A BIT FROM MODEL AVERAGES. SUNDAY AND MONDAY WILL FEATURE MILD CONDITIONS WITH HIGHS RETURNING CLOSE TO THE 70 DEGREE MARK ON THE PLAINS. BY LATE MONDAY OR TUESDAY...THE NEXT TROUGH WILL BE DROPPING INTO THE DESERT SOUTHWEST. THIS LOOKS TO BE A SLOW MOVER SO MAIN IMPACT OF THIS ONE MAY NOT REACH US UNTIL LATE NEXT WEEK. UNTIL THEN...WILL TREND FORECAST TOWARD COOLER TEMPERATURES TUESDAY AND WEDNESDAY WITH A FRONTAL PASSAGE LIKELY. WILL KEEP MOST POPS CONSERVATIVE AND MAINLY IN THE HIGH COUNTRY AS BEST LIFT WILL REMAIN WELL TO OUR WEST. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 800 PM MDT WED OCT 28 2015 WINDS HAVE ALREADY TRENDED TO SELY. APPEARS A WK SFC LOW WILL REMAIN NR DENVER OVERNIGHT WITH LATEST HRRR AND RAP KEEPING AN ESE COMPONENT THRU 12Z. && .BOU WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM MDT THURSDAY FOR COZ048>051. && $$ UPDATE...RPK SHORT TERM...KRIEDERMAN LONG TERM...BARJENBRUCH AVIATION...RPK
AREA FORECAST DISCUSSION
NWS NEW YORK NY
814 PM EDT WED OCT 28 2015 .SYNOPSIS... A WARM FRONT MOVES THROUGH...FOLLOWED BY A COLD FRONT LATE TONIGHT INTO THURSDAY. HIGH PRESSURE BUILDS IN FROM THE WEST FRIDAY AND SATURDAY...THEN MOVES OFF THE COAST SATURDAY NIGHT. A WEAKENING FRONTAL SYSTEM PASSES THROUGH LATE SATURDAY NIGHT INTO SUNDAY. HIGH PRESSURE OFF THE SOUTHEAST COAST BUILDS BACK INTO THE REGION SUNDAY NIGHT THROUGH TUESDAY. A WEAK LOW PASSES THROUGH THE MID ATLANTIC AND DELMARVA WEDNESDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... UPR LOW WAS INVOF THE MN/IA BORDER AT 21Z. SOLID BAND OF RAIN PRODUCING AROUND 3/4 INCH OF RAIN IN 2 HRS WAS LIFTING NEWD THRU THE CWA. ACROSS THE MID ATLANTIC...SHWRS WERE INCREASING WITH SCT TSTMS DEVELOPING...PARTICULARLY ACROSS NRN VA. BASED ON RADAR AND STLT...HAVE TWEAKED THE FCST SLIGHTLY TO INDICATE RAIN THIS EVE...FOLLOWED BY PERIODS OF RAIN WITH SCT TSTMS IN THE WARM SECTOR OVERNIGHT. THERE COULD BE A FEW BREAKS IN THE PCPN...BUT OUTSIDE OF THE HEAVIER ACTIVITY AT LEAST SOME LGT RAIN AND/DZ IS LIKELY...THEREFORE THE CHANGE. OTHERWISE...FCST WAS ON TRACK WITH THE BEST CHC FOR HEAVIEST SHWRS AND TSTMS WITH THE RR QUAD OF THE SUBTROPICAL JET LATE TNGT. WRT WINDS...AS INVERSION STRENGTHENS BEHIND THE WRMFNT...GUSTS SHOULD BECOME LESS FREQUENT...BUT SUSTAINED WINDS REMAIN RATHER STRONG. NO WIND RELATED HEADLINES...BUT CANNOT RULE OUT A FEW SUSTAINED WINDS IN EXCESS OF 30 MPH...OR A STRONG GUST OF 45 TO 50 MPH. GUSTS THOUGH DEPEND ON IF WINDS ALOFT MIX THROUGH THE INVERSION...WHICH IS NOT LIKELY. CHC OF 50+ MPH GUSTS IN ANY STRONGER TSTMS LATE TNGT. FOG IS EXPECTED AS WARM/MOIST AIR ADVECTS OVER THE SLIGHTLY COOLER WATER. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... MODEL ANALYSIS WOULD SUGGEST COLD FRONTAL PASSAGE AROUND 12Z...LIKELY CLEAR OF THE WESTERN HALF OF THE CWA BY 12Z. WILL MAINTAIN HIGH POPS FOR SHOWERS/ISOLATED THUNDER INITIALLY FOR EASTERN LOCALES...THEN MINIMAL POPS THROUGH THE MORNING BEHIND THE FRONT AS DRIER AIR COUNTERS ANY LINGERING WEAK LIFT ALOFT. UPPER CLOSED LOW OPENS AS IT TRAVERSES WELL TO THE NORTH OF THE AREA THROUGH THIS TIME FRAME. A VERY WARM DAY IS ANTICIPATED. AFTER A WARM START TO THE DAY...TEMPS WILL LIKELY PEAK IN THE LOWER TO MID 70S IN SPITE OF THE ONSET OF CAA BEHIND THE FRONT. A DRY NIGHT IS ANTICIPATED THURSDAY NIGHT AS A SERIES OF WEAK FRONTS MOVE THROUGH THURSDAY INTO THURSDAY NIGHT. AFTERNOON CU WILL SCATTER BY EVENING. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... A NEAR ZONAL UPPER FLOW WILL KEEP AN ACTIVE WEATHER PATTERN ACROSS THE NORTHEAST INTO EARLY NEXT WEEK...TUESDAY INTO WEDNESDAY...WHEN A WESTERN DEEP TROUGH AND EASTERN RIDGE DEVELOP INTO A BLOCKY PATTERN. HEIGHTS WILL BE RISING ACROSS THE REGION EARLY FRIDAY AS THE TROUGH AFFECTING THE REGION WEDNESDAY INTO THURSDAY OPENS AND WEAKENS..MOVING INTO EASTERN CANADA...AND THE ZONAL FLOW SETS UP. A NORTHERN STREAM SHORTWAVE IN THE UPPER PLAINS EARLY FRIDAY WILL BE MOVING QUICKLY EAST. THE WAVE WILL BE WEAKENING AND LIFTING INTO SOUTHERN CANADA SATURDAY INTO SUNDAY. AT THE SURFACE HIGH PRESSURE BUILDS IN FOR FRIDAY AND OVER THE REGION FRIDAY NIGHT INTO SATURDAY. A GUSTY NORTHWEST FLOW PREVAILS MUCH OF FRIDAY THEN WEAKENS AS COLD AIR ADVECTION AND WINDS ALOFT DIMINISH 18Z FRIDAY THROUGH 00Z SATURDAY. THE HIGH WILL BE OVER THE REGION FRIDAY NIGHT WITH CLEAR SKIES AND LIGHT WINDS...WITH AN IDEAL RADIATIONAL COOLING NIGHT IN PLACE. WARM ADVECTION SETS UP LATE SATURDAY AS THE UPPER RIDGE WEAKENS AND THE HIGH MOVES INTO THE WESTERN ATLANTIC. FOR LATE SATURDAY NIGHT THROUGH SUNDAY WITH THE WEAKENING SYSTEM PASSING WELL TO THE NORTH WILL HAVE SLIGHT CHANCE TO LOW CHANCE FOR LIGHT RAIN. THE GFS DOES DRY UP THE PRECIPITATION AS THE FRONTAL SYSTEM PASSES WHILE THE ECMWF WAS WET. THERE WILL BE MINIMAL RAINFALL IF ANY DOES OCCUR. WITH THE NORTHERN STEAM WAVE PASSING SUNDAY NIGHT HEIGHTS RISE ONCE AGAIN WITH A NEAR ZONAL FLOW. A SOUTHERN STREAM SHORTWAVE MOVING OUT OF TEXAS SUNDAY DAMPENS AS THE WAVE MOVES INTO THE CENTRAL APPALACHIANS AND PASSES OFF THE MID ATLANTIC. BOTH THE GFS AND ECMWF KEEP THE PRECIPITATION JUST SOUTH OF THE AREA MONDAY INTO TUESDAY AND EVEN THROUGH WPC BROUGHT IN SLIGHT CHANCE POPS ACROSS THE FAR SOUTH OPTED TO KEEP THE AREA DRY AS THE WAVE CONTINUES TO DAMPEN AND HEIGHTS ARE RISING. WEDNESDAY DRY EITHER WAY AS THE WAVE MOVES INTO THE WESTERN ATLANTIC AND NEARLY DISSIPATES AS THE HIGH OFFSHORE BUILDS BACK INTO THE AREA...SETTING UP THE BLOCKY PATTERN. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... WARM FROPA THIS EVENING WILL BE FOLLOWED BY COLD FROPA LATE TONIGHT. WIDESPREAD IFR AND LOCAL IFR FLIGHT CAT EXPECTED TONIGHT...WITH SECOND AREA OF MODERATE TO HEAVY RAIN MOVING IN THIS EVENING. WARM FROPA SHOULD OCCUR CLOSE TO MIDNIGHT...WITH SE SFC WINDS 15-20 KT WITH GUSTS 25-30 KT...A SECOND ROUND OF LLWS WITH SOUTHERLY WINDS 50-55 KT AT FL020...AND SCT TSTMS. COLD FROPA EXPECTED FROM WEST TO EAST FROM 09Z-12Z...FOLLOWED BY WIND SHIFT TO WSW AND GRADUAL IMPROVEMENT THEREAFTER TO VFR BY MID TO LATE MORNING. VFR WITH W WINDS 10-15G20-25 KT EXPECTED THU AFTERNOON. ...NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: BRIEF G25-30KT POSSIBLE 14Z-17Z THU. KLGA FCSTER COMMENTS: BRIEF G25-30KT POSSIBLE 14Z-17Z THU. KEWR FCSTER COMMENTS: BRIEF G25-30KT POSSIBLE 14Z-17Z THU. KTEB FCSTER COMMENTS: BRIEF G25-30KT POSSIBLE 14Z-17Z THU. KHPN FCSTER COMMENTS: BRIEF G25-30KT POSSIBLE 14Z-17Z THU. KISP FCSTER COMMENTS: BRIEF G25-30KT POSSIBLE 15Z-18Z THU. .OUTLOOK FOR 00Z FRI THROUGH MON... .THU NIGHT...VFR. DIMINISHING W WINDS. .FRI...VFR. WSW WINDS G20KT. .FRI NIGHT-SAT NIGHT...VFR. .SUNDAY...MVFR FLIGHT CAT POSSIBLE IN SHOWERS. .MON...VFR. && .MARINE... WITH A TIGHT PRESSURE GRADIENT IN PLACE BETWEEN DEPARTING HIGH PRESSURE TO THE EAST AND LOW PRESSURE WELL TO THE WEST...E-SE GALES SHIFT SE-S THIS EVENING AS A WARM FRONT LIFTS THROUGH. A COLD FRONT WILL PASS THROUGH LATE TONIGHT/EARLY THU. GALE FORCE WINDS LIKELY WEAKEN AFTER MIDNIGHT...BUT WILL MAINTAIN THE WARNING THROUGH TONIGHT AT THIS TIME AS WIND SPEEDS REMAIN CLOSE TO CRITERIA. WINDS BEHIND THE COLD FRONT TURN TOWARD THE WEST/SOUTHWEST THURSDAY...THEN TO THE WEST THURSDAY NIGHT. A FAIRLY TIGHT PRESSURE GRADIENT REMAINS IN PLACE...SO GUSTY WINDS CONTINUE. SEAS CONTINUE TO BUILD AND WILL BE QUITE ROUGH TONIGHT. SEAS SUBSIDE SLOWLY THURSDAY AND THURSDAY NIGHT...BUT REMAIN RATHER ROUGH FOR QUITE SOME TIME. SMALL CRAFT CONDITIONS WILL REMAIN ON THE OCEAN WATERS FRIDAY INTO FRIDAY EVENING. HIGH PRESSURE BUILDS OVER THE WATERS FRIDAY NIGHT AND SATURDAY WITH WINDS AND SEAS BELOW SMALL CRAFT ACROSS ALL THE FORECAST WATERS. WITH AN INCREASING SOUTHWEST FLOW AHEAD OF LOW PRESSURE WELL TO THE NORTH SEAS ON THE OCEAN WATERS MAY BUILD TO NEAR 5 FT BY LATE IN THE DAY...THEN SUBSIDE ONCE AGAIN SUNDAY NIGHT AS HIGH PRESSURE BUILDS BACK INTO THE WATERS. && .HYDROLOGY... ADDITIONAL RAIN OF AN INCH TO TWO INCHES IS EXPECTED. LOCALLY HIGHER AMOUNTS ARE POSSIBLE IN ANY HEAVIER SHOWERS/THUNDERSTORMS THROUGH TONIGHT. DUE NOT EXPECT FLASH FLOODING DUE TO RECENT DRY CONDITIONS AND RELATIVELY PROGRESSIVE NATURE OF THIS SYSTEM...BUT MINOR URBAN AND POOR DRAINAGE FLOODING IS POSSIBLE IN ANY OF THE HEAVIER RAIN. DRY WEATHER RETURNS THURSDAY AND THURSDAY NIGHT. NO PRECIPITATION IS EXPECTED FRIDAY THROUGH SATURDAY EVENING. A LIGHT RAINFALL IS POSSIBLE LATE SATURDAY NIGHT INTO SUNDAY EVENING. && .TIDES/COASTAL FLOODING... CSTL FLOOD ADVISORY HAS BEEN POSTED FOR THE FREEPORT GAUGE AREA THIS EVENING...WITH CSTL FLOOD STATEMENT FOR MOST OTHER LOCALES. THE NIGHT TIME HIGH TIDES ARE ASTRONOMICALLY LOWER...SO SIMILAR DEPARTURES WILL BRING LEVELS CLOSE TO BENCHMARKS. WINDS SHIFT TO THE SOUTH AND EVENTUALLY SW TONIGHT INTO THURSDAY AS A WARM FRONT MOVES THROUGH THIS EVENING...FOLLOWED BY A COLD FRONT THURSDAY EARLY MORNING. ADDITIONALLY...MINOR BEACH EROSION ISSUES ARE POSSIBLE DUE TO SURF BUILDING TO 5 TO 8 FT TONIGHT. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...COASTAL FLOOD ADVISORY UNTIL 11 PM EDT THIS EVENING FOR NYZ179. NJ...NONE. MARINE...GALE WARNING UNTIL 6 AM EDT THURSDAY FOR ANZ330-335-338-340- 345-350-353-355. && $$ SYNOPSIS...MET/PW NEAR TERM...JMC/PW SHORT TERM...PW LONG TERM...MET AVIATION...GOODMAN MARINE...MET/PW HYDROLOGY...MET/PW TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS LINCOLN IL
ISSUED BY NATIONAL WEATHER SERVICE CHICAGO IL 147 PM CDT TUE OCT 27 2015 .UPDATE... ISSUED AT 1059 AM CDT TUE OCT 27 2015 LOCAL RADAR IMAGERY AND OBS INDICATE WIDELY SCT LIGHT SHOWERS ONGOING ACROSS THE AREA. HOWEVER...MORE WIDESPREAD RAIN IS EXPECTED ACROSS THE REGION THIS AFTERNOON AND EVENING AS OUR NEXT SURGE OF MOISTURE...ASSOCIATED WITH THE NORTHWARD MOVING GULF LOW...SHIFTS NORTH-NORTHEASTWARD OVER EASTERN ILLINOIS INTO Indiana. THIS SHOULD RESULT IN A DECENT RAINFALL EVENT...WITH THE HIGHEST AMOUNTS LIKELY ACROSS MY EAST CENTRAL ILLINOIS COUNTIES...WHERE RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE ANTICIPATED. FARTHER WEST...AMOUNTS UP TO AN INCH ARE POSSIBLE. IT APPEARS THE THREAT OF THUNDER WILL BE VERY LOW TONIGHT...BUT NOT ZERO. THE BEST CHANCES OF EMBEDDED THUNDERSTORMS LOOKS TO BE ACROSS MY SOUTHERN AND EASTERN COUNTIES LATE TONIGHT...POSSIBLY INTO VERY EARLY Wednesday MORNING...JUST AHEAD OF AN EASTWARD ADVANCING COLD FRONTAL BOUNDARY. && .SHORT TERM...(Today) ISSUED AT 324 AM CDT TUE OCT 27 2015 08z/3am surface analysis shows ridge of high pressure extending from New England southwestward to the Central Plains...while a 1005mb low continues to spin over Louisiana. Showers from the Gulf Coast low have been slowly spreading northward over the past several hours, but have been encountering a very dry mid/low-level airmass beneath the surface ridge as evidenced by the 00z KILX upper air sounding and current surface dewpoints in the middle to upper 30s across the northern half of the CWA. This dry air has been impeding the northward progress of the precip...with 08z/3am radar imagery and surface obs indicating very light showers/sprinkles confined to locations along and south of a Litchfield to Paris line. HRRR has a decent handle on the current situation and suggests light rain will likely not make it north of the Peoria area until after sunrise. Have therefore cut back PoPs early this morning, especially across the far N/NW CWA where dry air will delay precip onset. Once the airmass moistens sufficiently and an upper-level trough approaching from the west provides increasing synoptic lift, rain will become widespread across the entire area by mid to late morning through the afternoon. Thanks to the rain and a brisk easterly wind of 10 to 15mph, high temperatures today will be considerably cooler than yesterday with readings remaining in the 50s in most locations. .LONG TERM...(Friday through Tuesday) ISSUED AT 145 PM CDT TUE OCT 27 2015 FRIDAY WILL BE A QUIET BUT COOL DAY AS TRANSITORY RIDGING BETWEEN THE DEPARTING TROUGH AND A DEEPENING UPPER LOW OVER THE SOUTHWEST. SURFACE HIGH PRESSURE OVER THE AREA WILL BE SHIFTING EAST...ALLOWING FOR SOME RECOVERIES FROM HIGHS ON THURSDAY. AFTER MOSTLY SUNNY SKIES TO START, CLOUD COVER INCREASES AS THE UPPER LOW TRANSLATES EAST. MODEST WARM AIR ADVECTION FRIDAY NIGHT INTO SATURDAY. MODELS DO NOT PAINT A CLEAR PICTURE AS TO HOW QUICKLY THE UPPER LOW WILL MOVE THROUGH THE REGION, AS THERE IS THE POTENTIAL FOR IT TO GET CUT OFF FROM THE NORTHERN STREAM FLOW. TO WHAT DEGREE THIS OCCURS WILL DIRECTLY TRANSLATE TO WHETHER THE WEEKEND WILL REMAIN OCCASIONALLY RAINY, OR IF A BREAK OCCURS ON SUNDAY BEFORE THE UPPER LOW MOVES THROUGH BY MONDAY. THEREFORE...WILL MAINTAIN THE HIGHEST RAIN CHANCES ON HALLOWEEN, FOLLOWED BY SOME CHANCE POPS SUNDAY/MONDAY WITH LOWER CONFIDENCE IN THESE TIME FRAMES. TEMPERATURES CONTINUE TO CLIMB BACK INTO THE 60S WITH PARTLY SUNNY/MOSTLY CLOUDY CONDITIONS. ONCE THE LOW SLIPS NORTHEAST, ANOMALOUSLY STRONG HIGH PRESSURE OVER THE SOUTHEAST AND ADJACENT ATLANTIC COAST WILL EXPAND NORTHWESTWARD AS ANOTHER DEEP UPPER LOW DIGS INTO THE SOUTHWESTERN UNITED STATES. THIS HIGHLY AMPLIFIED PATTERN SETS UP A WARM SOUTHWEST FLOW...RESULTING IN HIGH TEMPERATURES INTO THE 70S BY TUESDAY. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 1228 PM CDT TUE OCT 27 2015 WIDESPREAD LIFR CONDITIONS WILL REMAIN IN PLACE ACROSS THE AREA THROUGH THE AFTERNOON AND EVENING AS RAIN BANDS CONTINUE TO ROTATE NORTHWARD. UPSTREAM OBSERVATIONS SUGGEST SOME LIFTING CIGS ARE POSSIBLE, BUT WARM ADVECTION ABOVE THE COOL MOIST BOUNDARY LAYER SUGGESTS HOLDING THE LIFR CONDITIONS. VISIBILITY WILL VARY FROM 1-3 MILES AS THE RAIN BANDS MOVE THROUGH. THE PRESSURE GRADIENT SUPPORTS WINDS IN THE MID TEENS, WITH OCCASIONAL GUSTS POSSIBLE THOUGH WITH THE RAIN THE WIND GUSTS HAVE BEEN TEMPERED. ISOLATED TSRA DOES REMAIN POSSIBLE LATE TONIGHT INTO EARLY WEDNESDAY, BUT PROBABILITY STILL TOO LOW FOR MENTION IN TAFS AT THIS TIME. WINDS WILL VEER TO S-SW AFTER 09Z-12Z AND WEAKEN SOME AS THE DEEPENING LOW PRESSURE SYSTEM MOVES OVERHEAD. WINDS THEN TURN WSW BY MID MORNING WEDNESDAY AND QUICKLY INCREASE AS THE LOW LIFTS NORTHEAST. THERE WILL BE SOME SHOWERS BEHIND THE LOW, BUT THE BETTER CHANCES LOOK TO ARRIVE LATER IN THE DAY. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KB SHORT TERM...Barnes LONG TERM...KMD AVIATION...KMD
AREA FORECAST DISCUSSION
NWS LINCOLN IL
658 AM CDT TUE OCT 27 2015 .SHORT TERM...(Today) ISSUED AT 324 AM CDT TUE OCT 27 2015 08z/3am surface analysis shows ridge of high pressure extending from New England southwestward to the Central Plains...while a 1005mb low continues to spin over Louisiana. Showers from the Gulf Coast low have been slowly spreading northward over the past several hours, but have been encountering a very dry mid/low-level airmass beneath the surface ridge as evidenced by the 00z KILX upper air sounding and current surface dewpoints in the middle to upper 30s across the northern half of the CWA. This dry air has been impeding the northward progress of the precip...with 08z/3am radar imagery and surface obs indicating very light showers/sprinkles confined to locations along and south of a Litchfield to Paris line. HRRR has a decent handle on the current situation and suggests light rain will likely not make it north of the Peoria area until after sunrise. Have therefore cut back PoPs early this morning, especially across the far N/NW CWA where dry air will delay precip onset. Once the airmass moistens sufficiently and an upper-level trough approaching from the west provides increasing synoptic lift, rain will become widespread across the entire area by mid to late morning through the afternoon. Thanks to the rain and a brisk easterly wind of 10 to 15mph, high temperatures today will be considerably cooler than yesterday with readings remaining in the 50s in most locations. .LONG TERM...(Tonight through Monday) ISSUED AT 324 AM CDT TUE OCT 27 2015 Rain will continue tonight as the Louisiana low tracks northward across central Illinois. Forecast soundings remain quite stable, but do show modest elevated instability as the upper trough arrives. Think this may be just enough to produce a rumble or two of thunder, so will continue to mention isolated thunderstorms tonight. As the low lifts into the Great Lakes, showers will gradually diminish from southwest to northeast on Wednesday. Total rainfall with this system will generally be around 1 inch...with higher totals of 1 to 2 inches focused along/east of the I-57 corridor into the Ohio River Valley. Thanks to deepening surface low pressure over the Great Lakes and an approaching deep upper low, Thursday is shaping up to be the coolest day of the forecast period. Cloud cover associated with the upper system will likely remain just north of the CWA across northern Illinois. Despite abundant sunshine, brisk W/NW winds gusting to around 25mph will create a distinct chill as high temperatures struggle to reach the lower to middle 50s. After a very cool night Thursday night with lows dipping into the lower to middle 30s, temperatures will begin to rebound well into the 50s on Friday as high pressure drifts across the area. Models are still having trouble resolving the next potential system over the weekend. An upper low is expected to dive into the Desert Southwest on Friday, then slowly track E/NE through early next week. Exactly how quickly this process unfolds remains in question, as the models differ on how amplified the low will become. The 00z Oct 27 GEM is the deepest and furthest south with the low, keeping it over northwest Mexico until finally ejecting it northeastward into the Midwest by Tuesday. Meanwhile, the GFS and ECMWF are both more progressive...with the GFS tracking the low across the area on Sunday and the ECMWF on Monday. Given the considerable model spread, have opted to make few changes to the going forecast which follows the GFS closely. As a result, have introduced chance PoPs late Friday night into Saturday as a northern-stream wave approaches from the Northern Plains and have continued PoPs through Sunday night as the Desert Southwest low ejects northeastward. Have then gone with a dry forecast for Monday. Will need to watch future model trends closely...as further adjustments will likely be needed for the PoP forecast over the upcoming weekend. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) ISSUED AT 658 AM CDT TUE OCT 27 2015 Widespread MVFR ceilings are in place across central IL this morning with areas of showers providing IFR vsby/cigs. Isolated LIFR as well. Conditions will tend to deteriorate through this evening as responsible low pressure system continues to approach. Isolated TSRA possible overnight, but probability too low for mention in TAFS at this time. Widespread LIFR cigs/IFR vsby expected by 00Z. Winds E 10-15 kts with higher gusts during the afternoon hours. Winds veering to S-SW after 09Z- 12Z. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Onton
AREA FORECAST DISCUSSION
NWS LINCOLN IL
324 AM CDT TUE OCT 27 2015 .SHORT TERM...(Today) ISSUED AT 324 AM CDT TUE OCT 27 2015 08z/3am surface analysis shows ridge of high pressure extending from New England southwestward to the Central Plains...while a 1005mb low continues to spin over Louisiana. Showers from the Gulf Coast low have been slowly spreading northward over the past several hours, but have been encountering a very dry mid/low-level airmass beneath the surface ridge as evidenced by the 00z KILX upper air sounding and current surface dewpoints in the middle to upper 30s across the northern half of the CWA. This dry air has been impeding the northward progress of the precip...with 08z/3am radar imagery and surface obs indicating very light showers/sprinkles confined to locations along and south of a Litchfield to Paris line. HRRR has a decent handle on the current situation and suggests light rain will likely not make it north of the Peoria area until after sunrise. Have therefore cut back PoPs early this morning, especially across the far N/NW CWA where dry air will delay precip onset. Once the airmass moistens sufficiently and an upper-level trough approaching from the west provides increasing synoptic lift, rain will become widespread across the entire area by mid to late morning through the afternoon. Thanks to the rain and a brisk easterly wind of 10 to 15mph, high temperatures today will be considerably cooler than yesterday with readings remaining in the 50s in most locations. && .LONG TERM...(Tonight through Monday) ISSUED AT 324 AM CDT TUE OCT 27 2015 Rain will continue tonight as the Louisiana low tracks northward across central Illinois. Forecast soundings remain quite stable, but do show modest elevated instability as the upper trough arrives. Think this may be just enough to produce a rumble or two of thunder, so will continue to mention isolated thunderstorms tonight. As the low lifts into the Great Lakes, showers will gradually diminish from southwest to northeast on Wednesday. Total rainfall with this system will generally be around 1 inch...with higher totals of 1 to 2 inches focused along/east of the I-57 corridor into the Ohio River Valley. Thanks to deepening surface low pressure over the Great Lakes and an approaching deep upper low, Thursday is shaping up to be the coolest day of the forecast period. Cloud cover associated with the upper system will likely remain just north of the CWA across northern Illinois. Despite abundant sunshine, brisk W/NW winds gusting to around 25mph will create a distinct chill as high temperatures struggle to reach the lower to middle 50s. After a very cool night Thursday night with lows dipping into the lower to middle 30s, temperatures will begin to rebound well into the 50s on Friday as high pressure drifts across the area. Models are still having trouble resolving the next potential system over the weekend. An upper low is expected to dive into the Desert Southwest on Friday, then slowly track E/NE through early next week. Exactly how quickly this process unfolds remains in question, as the models differ on how amplified the low will become. The 00z Oct 27 GEM is the deepest and furthest south with the low, keeping it over northwest Mexico until finally ejecting it northeastward into the Midwest by Tuesday. Meanwhile, the GFS and ECMWF are both more progressive...with the GFS tracking the low across the area on Sunday and the ECMWF on Monday. Given the considerable model spread, have opted to make few changes to the going forecast which follows the GFS closely. As a result, have introduced chance PoPs late Friday night into Saturday as a northern-stream wave approaches from the Northern Plains and have continued PoPs through Sunday night as the Desert Southwest low ejects northeastward. Have then gone with a dry forecast for Monday. Will need to watch future model trends closely...as further adjustments will likely be needed for the PoP forecast over the upcoming weekend. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 1143 PM CDT MON OCT 26 2015 A developing low pressure system will lift into the Midwest Tuesday from the lower Mississippi Valley. The approach of this system, and associated rainfall, will have conditions across the central Illinois terminals rapidly decrease from VFR to IFR or lower late tonight into Tuesday morning. Once the rains and IFR conditions develop, they should linger through the 06Z TAF valid time and beyond. Easterly winds will prevail through the period to the north of the approaching low. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barnes LONG TERM...Barnes AVIATION...BAK
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1114 PM EDT WED OCT 28 2015 .UPDATE... ISSUED AT 1114 PM EDT WED OCT 28 2015 SHOWERS HAVE EXPANDED INTO A BROKEN LINE ACROSS NORTHERN KENTUCKY. THE LATEST HRRR HAS THIS MOVING THROUGH OUR AREA BETWEEN 05 AND 10Z. HAVE ADJUSTED THE POPS TOWARDS THIS SOLUTION SINCE IT HAS INITIALIZED FAIRLY WELL WITH THE CURRENT RADAR TRENDS. AS SUCH...WENT UP TO LIKELY POPS GENERALLY NEAR AND NORTH OF THE MOUNTAIN PARKWAY OVERNIGHT...WITH LESSER POPS TO THE SOUTHWEST. THIS BAND SHOULD GRADUALLY DIMINISH AS IT DROPS SOUTHEAST ACROSS OUR AREA. SOME OF THE VALLEYS HAVE ACTUALLY DECOUPLED THANKS TO PARTIALLY CLEARING SKIES OVERHEAD. THIS SHOULD BE TEMPORARY AS ADDITIONAL CLOUD COVER IS ALREADY STARTING TO FILL BACK IN UPSTREAM. DID UP THE LOWS A TOUCH BASED ON THE LATEST TRENDS IN OBSERVATIONS. UPDATE ISSUED AT 853 PM EDT WED OCT 28 2015 SHOWERS HAVE WANED IN AREAL COVERAGE ACROSS EASTERN KENTUCKY THIS EVENING...AS THE DRY SLOT HAS MOVED IN. MORE SHOWER ACTIVITY HAS POPPED UP FURTHER TO OUR NORTHWEST ASSOCIATED WITH THE SURFACE FRONT AND A MID-LEVEL SHORT WAVE TROUGH ROTATING THROUGH THE OHIO VALLEY. THIS WILL BE MOVING IN OVERNIGHT...WITH AN EXPECTED UPTICK IN ACTIVITY. HAVE UPDATED TO REMOVE THE MENTION OF THUNDER AS SCHEDULED...GIVEN THE DIMINISHMENT OF INSTABILITY. ALSO ALIGNED THE HOURLY TEMPERATURES AND DEW POINTS WITH THE CURRENT OBSERVATIONS TO ACCOUNT FOR THE SLOWER DROP OFF THROUGH THE EVENING HOURS. WILL TAKE A LOOK AT LOW TEMPERATURES A BIT LATER THIS EVENING. UPDATES HAVE BEEN SENT. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 257 PM EDT WED OCT 28 2015 SEVERAL BROKEN LINES/BANDS OF SHOWERS HAVE DEVELOPED ACROSS THE REGION THIS AFTERNOON. SEEING A FEW EMBEDDED ENHANCED ECHOES AS WELL. DECIDED TO KEEP MENTION OF ISOLD THUNDER UNTIL EARLY THIS EVENING WITH LOSE OF DAYTIME HEATING. EXPECT SHOWER ACTIVITY TO DIMINISH AGAIN WITH SUNSET. HOWEVER...FRONTAL BOUNDARY WILL PUSH INTO THE AREA LATE TONIGHT AND WITH IT WILL THE THREAT OF SHOWERS WILL RETURN. SEEING SOME SUPPORT FOR THIS LINE OF THINKING FROM THE HRRR AS WELL. BOUNDARY PUSHES OFF TO OUR EAST TOMORROW MORNING WHICH WILL USHER IN SOME DRYING AND FAIR WEATHER AS HIGH PRESSURE BEGINS TO BUILD INTO OHIO VALLEY. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 257 PM EDT WED OCT 28 2015 AT UPPER LEVELS...THE PERIOD BEGINS WITH SHORTWAVE RIDGING PUSHING OFF TO THE EAST SATURDAY BEFORE LOWER HEIGHTS AND SHORTWAVE TROUGHING MOVE IN FROM THE WEST. THE GFS AND ECMWF HAVE COME INTO BETTER AGREEMENT REGARDING THIS SYSTEM...BUT IT APPEARS THAT THE GFS IS STILL A BIT FASTER AND MORE PROGRESSIVE WITH THE SYSTEMS EXIT MONDAY NIGHT. RIDGING THEN BUILDS BACK INTO THE AREA BY THE END OF THE PERIOD. AT THE SURFACE...FRIDAY INTO SATURDAY MORNING SHOULD REMAIN COOL AND DRY WITH HIGH PRESSURE OVERHEAD. AS A SFC LOW MOVES NEWD FROM TX TOWARDS THE TENNESSEE VALLEY SATURDAY...MOISTURE AND CLOUD COVER WILL BUILD INTO THE REGION. RAIN CHANCES INCREASE BY SATURDAY EVENING AND CONTINUE THROUGH EARLY TUESDAY. AS OF RIGHT NOW...LOOKS LIKE THE MAJORITY OF THE RAIN WILL HOLD OFF UNTIL LATE SATURDAY NIGHT...WHICH LOOKS FAVORABLE FOR ANY OUTDOOR ACTIVITIES ON HALLOWEEN. RAIN WILL HANG AROUND THE AREA LATE SATURDAY THROUGH EARLY TUESDAY MORNING...WITH SOME SHOWERS LINGERING THROUGHOUT THE DAY TUESDAY BEFORE THE WEATHER DRIES OUT ON WEDNESDAY. TEMPERATURES WILL START OUT ON THE COOL SIDE FRIDAY BUT THEN BE SEASONABLE THROUGH SUNDAY. AFTERNOON HIGHS WILL THEN WARM INTO THE LOWER 70S MONDAY THROUGH WEDNESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 853 PM EDT WED OCT 28 2015 A COLD FRONT WILL PASS THROUGH EASTERN KENTUCKY TONIGHT. ONLY A STRAY SHOWER IS EXPECTED THROUGH AROUND 05Z...BEFORE SHOWERS BECOME MORE SCATTERED IN NATURE AS THE BOUNDARY MOVES THROUGH THE AREA. VFR CONDITIONS WITH SCATTERED TO BROKEN STRATOCU IN THE 4-6K FEET AGL RANGE WILL LOWER DOWN TO THE 2-3K FEET AGL RANGE FOR A COUPLE OF HOURS FOR ABOUT A 2 HOUR WINDOW OR SO BETWEEN 05 AND 11Z FROM NORTHWEST TO SOUTHEAST. CONDITIONS WILL IMPROVE THURSDAY AS HIGH PRESSURE GRADUALLY BUILDS INTO THE AREA FROM THE WEST. SOUTHWEST TO WEST WINDS AT 5 TO 10 KTS WILL CONTINUE ACROSS THE AREA THROUGH THURSDAY. OCCASIONAL GUSTS OF 15 TO 20 KTS WILL OCCUR OUT AHEAD OF FRONT AND ALONG IT...AS WELL AS DURING PEAK MIXING ON THURSDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEOGERIAN SHORT TERM...RAY LONG TERM...JVM AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
853 PM EDT WED OCT 28 2015 .UPDATE... ISSUED AT 853 PM EDT WED OCT 28 2015 SHOWERS HAVE WANED IN AREAL COVERAGE ACROSS EASTERN KENTUCKY THIS EVENING...AS THE DRY SLOT HAS MOVED IN. MORE SHOWER ACTIVITY HAS POPPED UP FURTHER TO OUR NORTHWEST ASSOCIATED WITH THE SURFACE FRONT AND A MID-LEVEL SHORT WAVE TROUGH ROTATING THROUGH THE OHIO VALLEY. THIS WILL BE MOVING IN OVERNIGHT...WITH AN EXPECTED UPTICK IN ACTIVITY. HAVE UPDATED TO REMOVE THE MENTION OF THUNDER AS SCHEDULED...GIVEN THE DIMINISHMENT OF INSTABILITY. ALSO ALIGNED THE HOURLY TEMPERATURES AND DEW POINTS WITH THE CURRENT OBSERVATIONS TO ACCOUNT FOR THE SLOWER DROP OFF THROUGH THE EVENING HOURS. WILL TAKE A LOOK AT LOW TEMPERATURES A BIT LATER THIS EVENING. UPDATES HAVE BEEN SENT. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 257 PM EDT WED OCT 28 2015 SEVERAL BROKEN LINES/BANDS OF SHOWERS HAVE DEVELOPED ACROSS THE REGION THIS AFTERNOON. SEEING A FEW EMBEDDED ENHANCED ECHOES AS WELL. DECIDED TO KEEP MENTION OF ISOLD THUNDER UNTIL EARLY THIS EVENING WITH LOSE OF DAYTIME HEATING. EXPECT SHOWER ACTIVITY TO DIMINISH AGAIN WITH SUNSET. HOWEVER...FRONTAL BOUNDARY WILL PUSH INTO THE AREA LATE TONIGHT AND WITH IT WILL THE THREAT OF SHOWERS WILL RETURN. SEEING SOME SUPPORT FOR THIS LINE OF THINKING FROM THE HRRR AS WELL. BOUNDARY PUSHES OFF TO OUR EAST TOMORROW MORNING WHICH WILL USHER IN SOME DRYING AND FAIR WEATHER AS HIGH PRESSURE BEGINS TO BUILD INTO OHIO VALLEY. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 257 PM EDT WED OCT 28 2015 AT UPPER LEVELS...THE PERIOD BEGINS WITH SHORTWAVE RIDGING PUSHING OFF TO THE EAST SATURDAY BEFORE LOWER HEIGHTS AND SHORTWAVE TROUGHING MOVE IN FROM THE WEST. THE GFS AND ECMWF HAVE COME INTO BETTER AGREEMENT REGARDING THIS SYSTEM...BUT IT APPEARS THAT THE GFS IS STILL A BIT FASTER AND MORE PROGRESSIVE WITH THE SYSTEMS EXIT MONDAY NIGHT. RIDGING THEN BUILDS BACK INTO THE AREA BY THE END OF THE PERIOD. AT THE SURFACE...FRIDAY INTO SATURDAY MORNING SHOULD REMAIN COOL AND DRY WITH HIGH PRESSURE OVERHEAD. AS A SFC LOW MOVES NEWD FROM TX TOWARDS THE TENNESSEE VALLEY SATURDAY...MOISTURE AND CLOUD COVER WILL BUILD INTO THE REGION. RAIN CHANCES INCREASE BY SATURDAY EVENING AND CONTINUE THROUGH EARLY TUESDAY. AS OF RIGHT NOW...LOOKS LIKE THE MAJORITY OF THE RAIN WILL HOLD OFF UNTIL LATE SATURDAY NIGHT...WHICH LOOKS FAVORABLE FOR ANY OUTDOOR ACTIVITIES ON HALLOWEEN. RAIN WILL HANG AROUND THE AREA LATE SATURDAY THROUGH EARLY TUESDAY MORNING...WITH SOME SHOWERS LINGERING THROUGHOUT THE DAY TUESDAY BEFORE THE WEATHER DRIES OUT ON WEDNESDAY. TEMPERATURES WILL START OUT ON THE COOL SIDE FRIDAY BUT THEN BE SEASONABLE THROUGH SUNDAY. AFTERNOON HIGHS WILL THEN WARM INTO THE LOWER 70S MONDAY THROUGH WEDNESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 853 PM EDT WED OCT 28 2015 A COLD FRONT WILL PASS THROUGH EASTERN KENTUCKY TONIGHT. ONLY A STRAY SHOWER IS EXPECTED THROUGH AROUND 05Z...BEFORE SHOWERS BECOME MORE SCATTERED IN NATURE AS THE BOUNDARY MOVES THROUGH THE AREA. VFR CONDITIONS WITH SCATTERED TO BROKEN STRATOCU IN THE 4-6K FEET AGL RANGE WILL LOWER DOWN TO THE 2-3K FEET AGL RANGE FOR A COUPLE OF HOURS FOR ABOUT A 2 HOUR WINDOW OR SO BETWEEN 05 AND 11Z FROM NORTHWEST TO SOUTHEAST. CONDITIONS WILL IMPROVE THURSDAY AS HIGH PRESSURE GRADUALLY BUILDS INTO THE AREA FROM THE WEST. SOUTHWEST TO WEST WINDS AT 5 TO 10 KTS WILL CONTINUE ACROSS THE AREA THROUGH THURSDAY. OCCASIONAL GUSTS OF 15 TO 20 KTS WILL OCCUR OUT AHEAD OF FRONT AND ALONG IT...AS WELL AS DURING PEAK MIXING ON THURSDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEOGERIAN SHORT TERM...RAY LONG TERM...JVM AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
602 PM EDT TUE OCT 27 2015 .SYNOPSIS... STRONG LOW PRESSURE WILL BRING RAIN THROUGH WEDNESDAY NIGHT. SEASONABLY COOL TEMPERATURES ARE EXPECTED THROUGH THE REST OF THE WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... WITH 6PM UPDATE...HAVE SLIGHTLY REDUCED POPS OVER THE NEXT 2-3 HOURS WITH MOST RADAR ECHOES NOT EXPECTED TO MAKE IT TO THE GROUND...BUT THEN INCREASED POPS THROUGH MIDNIGHT TO ACCOUNT FOR SOME BRIEF BANDING OF RAINFALL SHOWN IN MODEL FORECASTS. NO CHANGES HAVE BEEN MADE TO WIND HEADLINES AT THIS POINT...BUT WILL CONTINUE TO MONITOR POSSIBILITY THAT THE WIND ADVISORY MAY NEED TO BE FURTHER EXPANDED IN COVERAGE. THAT SCENARIO WAS EXPLAINED WELL IN THE PREVIOUS DISCUSSION...WHICH FOLLOWS BELOW. MOISTURE WILL CONTINUE TO INCREASE FROM THE SOUTH AHEAD OF THE REMNANTS OF PATRICIA. A RELATIVELY LONG PERIOD OF WET CONDITIONS WILL BE LIKELY OVER THE NEXT COUPLE OF DAYS AS THE MOISTURE FROM THE REMNANTS GET ABSORBED BY A VERY DEEP CLOSED UPPER LOW THAT WILL MOVE FROM THE GREAT LAKES THROUGH THE NORTHEAST THIS WEEK. DEEP SOUTHEASTERLY FLOW WILL INCREASE GOING INTO THE EVENING AS MOISTURE INCREASES. MULTI-MODEL CONSENSUS VALUES SUGGEST THE LOW LEVEL JET MAXIMA MAY WELL APPROACH 60-70 KTS FROM THE SOUTHEAST OVERNIGHT TONIGHT INTO WEDNESDAY MORNING. ADDITIONALLY...MODEL SOUNDINGS FAVOR INVERSION HEIGHTS SLIGHTLY ABOVE THE RIDGETOPS WITH SOUTHEASTERLY FLOW BEING PERPENDICULAR TO THE RIDGELINES. THIS COMBINED WITH FAIRLY UNSTABLE CONDITIONS BELOW THE INVERSION HEIGHTS...AS WELL AS PRECIPITATION DRAG WILL LIKELY MIX DOWN A FAIR AMOUNT OF WIND GUSTS. EVEN BELOW THE INVERSION LEVEL...NAM CONUS NEST PLOTS AND HRRR VALUES SUGGEST 45-55 KTS OF WIND GUST POTENTIAL IN CHESTNUT/LAUREL RIDGES AS WELL AS DOWNSLOPE MOUNTAIN WAVE WIND GUST POTENTIAL TO THE WEST OF THE RIDGES. DUE TO THE ORIENTATION OF THE TOPOGRAPHY RELATIVE TO THE FLOW...THIS FAVORS WIND GUST POTENTIAL PRIMARILY IN FAYETTE AND WESTMORELAND COUNTIES...AS WELL AS FAR SOUTHEASTERN INDIANA COUNTY. THE POTENTIAL IS A BIT LESS IN WEST VIRGINIA AND MARYLAND. THAT SAID...WITH GUSTS TO 50 MPH IN THE FORECAST...A WIND ADVISORY HAS BEEN ISSUED FOR WESTMORELAND AND FAYETTE COUNTIES. AS FLOW TURNS MORE SOUTHERLY ON WEDNESDAY IN ADVANCE OF THE APPROACHING WAVE...MOUNTAIN WAVE GUST POTENTIAL DECREASES SUBSTANTIALLY AS THE FLOW DIRECTION CHANGES AND THE LOW LEVEL JET LIFTS NORTHWARD. HOWEVER...AHEAD OF THE INCOMING FRONTAL BOUNDARY...DEEPER STEEP LAPSE RATES MOVE IN FROM THE WEST. THIS WILL ALLOW FOR THE RAIN SHADOW TO THE WEST OF THE RIDGES TO BE ERADICATED AS DEEPER LIFT ASSOCIATED WITH THE INCOMING JET STREAK AND DIFFERENTIAL PVA COUPLED WITH SKINNY CAPE ALONG THE FRONT MAY ALLOW FOR SOME THUNDERSTORM DEVELOPMENT. SHOULD A DECENT LINE FORM ALONG THE FRONT...GIVEN THE MOMENTUM IN THE COLUMN...A SEVERE WIND GUST OR TWO WILL BE POSSIBLE BY LATE AFTERNOON AND EVENING. SPC HAS OUTLINED THIS POSSIBILITY WITH A MARGINAL RISK...AND GIVEN THE LACK OF INSTABILITY...THIS SEEMS A PRAGMATIC APPROACH. A SLIGHT CHANCE OF THUNDERSTORMS WAS INCLUDED IN THE FORECAST...HOWEVER THE CHANCES OF SEVERE WEATHER DO NOT LOOK OVERLY IMPRESSIVE AT THIS TIME. IN ADVANCE OF THE SYSTEM OVERNIGHT...TEMPERATURES MAY WELL RISE DUE TO INCREASING MIXING...AND CONTINUE TO WARM ON WEDNESDAY MORNING AHEAD OF THE COLD FRONT. A FEW SPOTS MAY WELL TOUCH 70F BEFORE THE FRONT CROSSES AS THE UPPER LOW DROPS OVERHEAD LATER IN THE WEEK. FRIES && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... A SECONDARY COLD FRONT WILL CROSS EARLY THURSDAY MORNING... NECESSITATING THE INCLUSION OF CHANCE POPS UNTIL ITS EXIT. MORE IMPORTANTLY...PRESSURE RISES IMMEDIATELY BEHIND THE FRONT WILL BE RATHER SIGNIFICANT...WHICH LEADS TO CONCERN FOR STRONG WIND GUSTS THROUGH THE AFTERNOON. BUFKIT SOUNDINGS CONTINUE TO SHOW THIS DEEP MIXING LAYER WITH WIND AT THE TOP OF THE INVERSION APPROACHING 40-45KTS. WITH SOME UNCERTAINTY IN HOW MUCH OF THIS WIND WILL TRANSLATE TO THE SURFACE...HAVE OPTED TO MENTION THE THREAT IN THE HWO. ONCE THE SHOWERS END THURSDAY MORNING...EXPECT A DRY REMAINDER OF THE DAY...WITH DECREASING CLOUD COVER. THE UPPER TROUGH WILL FINALLY PIVOT TO THE EAST THURSDAY NIGHT...RETURNING THE REGION TO COLD NORTHWEST FLOW. CHANCE POPS WERE MAINTAINED OVERNIGHT THURSDAY WITH SOME COLD ADVECTION LAKE ENHANCED SHOWERS POSSIBLE. OTHERWISE...TEMPERATURES LOOK TO STAY BELOW SEASONAL AVERAGES BOTH THURSDAY AND FRIDAY. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... A PROGRESSIVE FLOW PATTERN SHOULD RESULT IN A VARIABLE LONG TERM PERIOD WITH SHORTWAVE RIDGING FORECAST TO PROVIDE A DRY START TO THE WEEKEND...BUT ANOTHER TROUGH MOVING OUT OF THE MIDWEST IS TIMED TO DETERIORATE CONDITIONS WITH RAIN BY SUNDAY. SHORTWAVE RIDGING WOULD AGAIN DRY THE PROGNOSIS EARLY IN THE NEW WORK-WEEK. THE LONG TERM FORECAST WAS CONSTRUCTED USING A BLEND OF WPC AND GFSMOS GUIDANCE AND GENERALLY FEATURES CLIMO POPS AND TEMPS AT...OR A FEW DEGREES ABOVE THE AVERAGES. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... VFR CONDITIONS SHOULD CONTINUE AT MOST OF THE TAF LOCATIONS UNTIL AFTER SUNSET AS THE LOW AND MID LEVELS FINALLY SATURATE. MANY OF THE RETURNS CURRENTLY ON THE RADAR CONTINUE TO DISSIPATE AS THEY MOVE NORTHWARD INTO DRIER AIR. SO...THE TIMING OF THE ONSET OF PRECIPITATION AND RESTRICTIONS WAS PUSHED BACK A BIT ACROSS ALL TERMINALS. EXPECT A GRADUAL DETERIORATION OVERNIGHT WITH RESTRICTIONS LIKELY TO CONTINUE THROUGH MOST OF WEDNESDAY. IN ADDITION TO CIG AND SOME VSBY RESTRICTIONS...GUSTY ESE WIND WILL BE POSSIBLE TOWARD WEDNESDAY MORNING...ESPECIALLY AT THE TERMINALS CLOSEST TO THE RIDGES. HAVE OPTED TO CARRY GUSTS VERSUS LLWS THOUGH THE CONCERN IS THERE FURTHER WEST. OUTLOOK...WEDNESDAY THROUGH SUNDAY/... RESTRICTIONS ARE LIKELY THROUGH THURSDAY UNTIL A STRONG COLD FRONT CROSSES THE REGION. STRONG WIND GUSTS OR LOW LEVEL WIND SHEAR WILL ALSO BE POSSIBLE. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...WIND ADVISORY FROM 2 AM TO 11 AM EDT WEDNESDAY FOR PAZ073>076. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
341 PM EDT TUE OCT 27 2015 .SYNOPSIS... STRONG LOW PRESSURE WILL BRING RAIN THROUGH WEDNESDAY NIGHT. SEASONABLY COOL TEMPERATURES ARE EXPECTED THROUGH THE REST OF THE WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... MOISTURE WILL CONTINUE TO INCREASE FROM THE SOUTH AHEAD OF THE REMNANTS OF PATRICIA. A RELATIVELY LONG PERIOD OF WET CONDITIONS WILL BE LIKELY OVER THE NEXT COUPLE OF DAY AS THE MOISTURE FROM THE REMNANTS GET ABSORBED BY A VERY DEEP CLOSED UPPER LOW THAT WILL MOVE FROM THE GREAT LAKES THROUGH THE NORTHEAST THIS WEEK. DEEP SOUTHEASTERLY FLOW WILL INCREASE GOING INTO THE EVENING AS MOISTURE INCREASES. MULTI-MODEL CONSENSUS VALUES SUGGEST THE LOW LEVEL JET MAXIMA MAY WELL APPROACH 60-70 KTS FROM THE SOUTHEAST OVERNIGHT TONIGHT INTO WEDNESDAY MORNING. ADDITIONALLY...MODEL SOUNDINGS FAVOR INVERSION HEIGHTS SLIGHTLY ABOVE THE RIDGETOPS WITH SOUTHEASTERLY FLOW BEING PERPENDICULAR TO THE RIDGELINES. THIS COMBINED WITH FAIRLY UNSTABLE CONDITIONS BELOW THE INVERSION HEIGHTS...AS WELL AS PRECIPITATION DRAG WILL LIKELY MIX DOWN A FAIR AMOUNT OF WIND GUSTS. EVEN BELOW THE INVERSION LEVEL...NAM CONUS NEST PLOTS AND HRRR VALUES SUGGEST 45-55 KTS OF WIND GUST POTENTIAL IN CHESTNUT/LAUREL RIDGES AS WELL AS DOWNSLOPE MOUNTAIN WAVE WIND GUST POTENTIAL TO THE WEST OF THE RIDGES. DUE TO THE ORIENTATION OF THE TOPOGRAPHY RELATIVE TO THE FLOW...THIS FAVORS WIND GUST POTENTIAL PRIMARILY IN FAYETTE AND WESTMORELAND COUNTIES...AS WELL AS FAR SOUTHEASTERN INDIANA COUNTY. THE POTENTIAL IS A BIT LESS IN WEST VIRGINIA AND MARYLAND. THAT SAID...WITH GUSTS TO 50 MPH IN THE FORECAST...A WIND ADVISORY HAS BEEN ISSUED FOR WESTMORELAND AND FAYETTE COUNTIES. AS FLOW TURNS MORE SOUTHERLY ON WEDNESDAY IN ADVANCE OF THE APPROACHING WAVE...MOUNTAIN WAVE GUST POTENTIAL DECREASES SUBSTANTIALLY AS THE FLOW DIRECTION CHANGES AND THE LOW LEVEL JET LIFTS NORTHWARD. HOWEVER...AHEAD OF THE INCOMING FRONTAL BOUNDARY...DEEPER STEEP LAPSE RATES MOVE IN FROM THE WEST. THIS WILL ALLOW FOR THE RAIN SHADOW TO THE WEST OF THE RIDGES TO BE ERADICATED AS DEEPER LIFT ASSOCIATED WITH THE INCOMING JET STREAK AND DIFFERENTIAL PVA COUPLED WITH SKINNY CAPE ALONG THE FRONT MAY ALLOW FOR SOME THUNDERSTORM DEVELOPMENT. SHOULD A DECENT LINE FORM ALONG THE FRONT...GIVEN THE MOMENTUM IN THE COLUMN...A SEVERE WIND GUST OR TWO WILL BE POSSIBLE BY LATE AFTERNOON AND EVENING. SPC HAS OUTLINED THIS POSSIBILITY WITH A MARGINAL RISK...AND GIVEN THE LACK OF INSTABILITY...THIS SEEMS A PRAGMATIC APPROACH. A SLIGHT CHANCE OF THUNDERSTORMS WAS INCLUDED IN THE FORECAST...HOWEVER THE CHANCES OF SEVERE WEATHER DO NOT LOOK OVERLY IMPRESSIVE AT THIS TIME. IN ADVANCE OF THE SYSTEM OVERNIGHT...TEMPERATURES MAY WELL RISE DUE TO INCREASING MIXING...AND CONTINUE TO WARM ON WEDNESDAY MORNING AHEAD OF THE COLD FRONT. A FEW SPOTS MAY WELL TOUCH 70F BEFORE THE FRONT CROSSES AS THE UPPER LOW DROPS OVERHEAD LATER IN THE WEEK. FRIES && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... A SECONDARY COLD FRONT WILL CROSS EARLY THURSDAY MORNING... NECESSITATING THE INCLUSION OF CHANCE POPS UNTIL ITS EXIT. MORE IMPORTANTLY...PRESSURE RISES IMMEDIATELY BEHIND THE FRONT WILL BE RATHER SIGNIFICANT...WHICH LEADS TO CONCERN FOR STRONG WIND GUSTS THROUGH THE AFTERNOON. BUFKIT SOUNDINGS CONTINUE TO SHOW THIS DEEP MIXING LAYER WITH WIND AT THE TOP OF THE INVERSION APPROACHING 40-45KTS. WITH SOME UNCERTAINTY IN HOW MUCH OF THIS WIND WILL TRANSLATE TO THE SURFACE...HAVE OPTED TO MENTION THE THREAT IN THE HWO. ONCE THE SHOWERS END THURSDAY MORNING...EXPECT A DRY REMAINDER OF THE DAY...WITH DECREASING CLOUD COVER. THE UPPER TROUGH WILL FINALLY PIVOT TO THE EAST THURSDAY NIGHT...RETURNING THE REGION TO COLD NORTHWEST FLOW. CHANCE POPS WERE MAINTAINED OVERNIGHT THURSDAY WITH SOME COLD ADVECTION LAKE ENHANCED SHOWERS POSSIBLE. OTHERWISE...TEMPERATURES LOOK TO STAY BELOW SEASONAL AVERAGES BOTH THURSDAY AND FRIDAY. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... A PROGRESSIVE FLOW PATTERN SHOULD RESULT IN A VARIABLE LONG TERM PERIOD WITH SHORTWAVE RIDGING FORECAST TO PROVIDE A DRY START TO THE WEEKEND...BUT ANOTHER TROUGH MOVING OUT OF THE MIDWEST IS TIMED TO DETERIORATE CONDITIONS WITH RAIN BY SUNDAY. SHORTWAVE RIDGING WOULD AGAIN DRY THE PROGNOSIS EARLY IN THE NEW WORK-WEEK. THE LONG TERM FORECAST WAS CONSTRUCTED USING A BLEND OF WPC AND GFSMOS GUIDANCE AND GENERALLY FEATURES CLIMO POPS AND TEMPS AT...OR A FEW DEGREES ABOVE THE AVERAGES. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... VFR CONDITIONS SHOULD CONTINUE AT MOST OF THE TAF LOCATIONS UNTIL AFTER SUNSET AS THE LOW AND MID LEVELS FINALLY SATURATE. MANY OF THE RETURNS CURRENTLY ON THE RADAR CONTINUE TO DISSIPATE AS THEY MOVE NORTHWARD INTO DRIER AIR. SO...THE TIMING OF THE ONSET OF PRECIPITATION AND RESTRICTIONS WAS PUSHED BACK A BIT ACROSS ALL TERMINALS. EXPECT A GRADUAL DETERIORATION OVERNIGHT WITH RESTRICTIONS LIKELY TO CONTINUE THROUGH MOST OF WEDNESDAY. IN ADDITION TO CIG AND SOME VSBY RESTRICTIONS...GUSTY ESE WIND WILL BE POSSIBLE TOWARD WEDNESDAY MORNING...ESPECIALLY AT THE TERMINALS CLOSEST TO THE RIDGES. HAVE OPTED TO CARRY GUSTS VERSUS LLWS THOUGH THE CONCERN IS THERE FURTHER WEST. OUTLOOK...WEDNESDAY THROUGH SATURDAY/... RESTRICTIONS ARE LIKELY THROUGH THURSDAY UNTIL A STRONG COLD FRONT CROSSES THE REGION. STRONG WIND GUSTS OR LOW LEVEL WIND SHEAR WILL ALSO BE POSSIBLE. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...WIND ADVISORY FROM 2 AM TO 11 AM EDT WEDNESDAY FOR PAZ073>076. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1156 AM EDT TUE OCT 27 2015 .SYNOPSIS... STRONG LOW PRESSURE WILL BRING RAIN THROUGH WEDNESDAY NIGHT. SEASONABLY COOL TEMPERATURES ARE EXPECTED THROUGH THE REST OF THE WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... MOISTURE WILL CONTINUE TO INCREASE FROM THE SOUTH AHEAD OF THE REMNANTS OF PATRICIA. A RELATIVELY LONG PERIOD OF WET CONDITIONS WILL BE LIKELY OVER THE NEXT COUPLE OF DAY AS THE MOISTURE FROM THE REMNANTS GET ABSORBED BY A VERY DEEP CLOSED UPPER LOW THAT WILL MOVE FROM THE GREAT LAKES THROUGH THE NORTHEAST THIS WEEK. DEEP SOUTHEASTERLY FLOW WILL INCREASE GOING INTO THE EVENING AS MOISTURE INCREASES. MULTI-MODEL CONSENSUS VALUES SUGGEST THE LOW LEVEL JET MAXIMA MAY WELL APPROACH 60-70 KTS FROM THE SOUTHEAST OVERNIGHT TONIGHT INTO WEDNESDAY MORNING. ADDITIONALLY...MODEL SOUNDINGS FAVOR INVERSION HEIGHTS SLIGHTLY ABOVE THE RIDGETOPS WITH SOUTHEASTERLY FLOW BEING PERPENDICULAR TO THE RIDGELINES. THIS COMBINED WITH FAIRLY UNSTABLE CONDITIONS BELOW THE INVERSION HEIGHTS...AS WELL AS PRECIPITATION DRAG WILL LIKELY MIX DOWN A FAIR AMOUNT OF WIND GUSTS. EVEN BELOW THE INVERSION LEVEL...NAM CONUS NEST PLOTS AND HRRR VALUES SUGGEST 45-55 KTS OF WIND GUST POTENTIAL IN CHESTNUT/LAUREL RIDGES AS WELL AS DOWNSLOPE MOUNTAIN WAVE WIND GUST POTENTIAL TO THE WEST OF THE RIDGES. DUE TO THE ORIENTATION OF THE TOPOGRAPHY RELATIVE TO THE FLOW...THIS FAVORS WIND GUST POTENTIAL PRIMARILY IN FAYETTE AND WESTMORELAND COUNTIES...AS WELL AS FAR SOUTHEASTERN INDIANA COUNTY. THE POTENTIAL IS A BIT LESS IN WEST VIRGINIA AND MARYLAND. THAT SAID...WITH GUSTS TO 50 MPH IN THE FORECAST...A WIND ADVISORY HAS BEEN ISSUED FOR WESTMORELAND AND FAYETTE COUNTIES. AS FLOW TURNS MORE SOUTHERLY ON WEDNESDAY IN ADVANCE OF THE APPROACHING WAVE...MOUNTAIN WAVE GUST POTENTIAL DECREASES SUBSTANTIALLY AS THE FLOW DIRECTION CHANGES AND THE LOW LEVEL JET LIFTS NORTHWARD. HOWEVER...AHEAD OF THE INCOMING FRONTAL BOUNDARY...DEEPER STEEP LAPSE RATES MOVE IN FROM THE WEST. THIS WILL ALLOW FOR THE RAIN SHADOW TO THE WEST OF THE RIDGES TO BE ERADICATED AS DEEPER LIFT ASSOCIATED WITH THE INCOMING JET STREAK AND DIFFERENTIAL PVA COUPLED WITH SKINNY CAPE ALONG THE FRONT MAY ALLOW FOR SOME THUNDERSTORM DEVELOPMENT. SHOULD A DECENT LINE FORM ALONG THE FRONT...GIVEN THE MOMENTUM IN THE COLUMN...A SEVERE WIND GUST OR TWO WILL BE POSSIBLE BY LATE AFTERNOON AND EVENING. SPC HAS OUTLINED THIS POSSIBILITY WITH A MARGINAL RISK...AND GIVEN THE LACK OF INSTABILITY...THIS SEEMS A PRAGMATIC APPROACH. A SLIGHT CHANCE OF THUNDERSTORMS WAS INCLUDED IN THE FORECAST...HOWEVER THE CHANCES OF SEVERE WEATHER DO NOT LOOK OVERLY IMPRESSIVE AT THIS TIME. IN ADVANCE OF THE SYSTEM OVERNIGHT...TEMPERATURES MAY WELL RISE DUE TO INCREASING MIXING...AND CONTINUE TO WARM ON WEDNESDAY MORNING AHEAD OF THE COLD FRONT. A FEW SPOTS MAY WELL TOUCH 70F BEFORE THE FRONT CROSSES AS THE UPPER LOW DROPS OVERHEAD LATER IN THE WEEK. FRIES && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/... A SECONDARY COLD FRONT WILL CROSS EARLY THURSDAY MORNING... NECESSITATING THE INCLUSION OF CHANCE POPS UNTIL ITS EXIT. HAVE INCREASED WINDS ALONG AND DIRECTLY BEHIND THE COLD FRONT AS BUFKIT SOUNDINGS SHOW A DEEP MIXING LAYER AND PLENTY OF WIND JUST ABOVE THE SURFACE. DO NOT EXPECT THE STRONGEST WINDS TO MIX DOWN TO THE SURFACE...AS BOUNDARY LAYER STABILIZES...BUT IT WILL BE RATHER GUSTY FOR A TIME ON THURSDAY. ONCE THE SHOWERS END THURSDAY MORNING...EXPECT A DRY REMAINDER OF THE DAY...WITH DECREASING CLOUD COVER. THURSDAY LOOKS LIKE A DAY OF NEARLY STEADY TEMPERATURES WITH THE STRONG COLD AIR ADVECTION BEHIND THE FRONT. HIGHS THURSDAY WILL LIKELY BE AIDED SOMEWHAT BY THE LATE OCTOBER SUN. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... A PROGRESSIVE FLOW PATTERN SHOULD RESULT IN A VARIABLE LONG TERM PERIOD WITH SHORTWAVE RIDGING FORECAST TO PROVIDE A DRY START TO THE WEEKEND...BUT ANOTHER TROUGH MOVING OUT OF THE MIDWEST IS TIMED TO DETERIORATE CONDITIONS WITH RAIN BY SUNDAY. SHORTWAVE RIDGING WOULD AGAIN DRY THE PROGNOSIS EARLY IN THE NEW WORK-WEEK. THE LONG TERM FORECAST WAS CONSTRUCTED USING A BLEND OF WPC AND GFSMOS GUIDANCE AND GENERALLY FEATURES CLIMO POPS AND TEMPS AT...OR A FEW DEGREES ABOVE THE AVERAGES. && .AVIATION /16Z TUESDAY THROUGH SATURDAY/... VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE DAY ALTHOUGH LIGHT RAIN IS EXPECTED TO ENCROACH FROM THE SOUTH AS THE AFTN PROGRESSES. CONDITION DETERIORATION CAN BE ANTICIPATED AFTER DARK AS THE LLVLS SATURATE. OUTLOOK...WEDNESDAY THROUGH SATURDAY/... LOW LEVEL WIND SHEAR AND RESTRICTIONS ARE LIKELY THROUGH THURSDAY AS STRONG LOW PRES CROSSES THE MIDWEST AND EASTERN CANADA AND PULLS A CDFNT ACRS THE REGION. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...WIND ADVISORY FROM 2 AM TO 11 AM EDT WEDNESDAY FOR PAZ073>076. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1153 PM EDT WED OCT 28 2015 .AVIATION... STRONG COLD FRONT WILL TRACK ACROSS ALL TERMINALS EARLY THIS MORNING. OBSERVATIONS CONTINUE TO INDICATE A WINDOW FOR STRONGER SOUTHWESTERLY GUSTS ALONG AND IMMEDIATELY BEHIND THIS FRONT AND THE ACCOMPANYING LINE OF SHOWERS. STRONGEST GUSTS /35 KNOT RANGE/ THROUGH 08Z. ANOTHER PEAK IN SOUTHWESTERLY GUSTS AS MIXING ENSUES AFTER 13Z...AGAIN LOOKING AT HIGH END GUSTS REACHING 35 KNOTS. PASSING SHOWERS WILL PROVIDE A PERIOD OF MVFR AS WELL. POTENTIAL FOR CEILINGS TO LIFT BACK INTO VFR IN THE WAKE OF THIS MOISTURE. COLDER SOUTHWEST FLOW WILL ALLOW SOME LAKE MODIFIED MOISTURE TO WORK DOWNSTREAM ON THURSDAY. THIS WILL BRING A GREATER POTENTIAL FOR HIGHER COVERAGE OF LOWER CLOUD /MVFR/ AND POSSIBLY SOME SHOWERS TO IMPACT MAINLY MBS/FNT DURING THE DAYLIGHT PERIOD. FOR DTW...COLD FRONTAL PASSAGE WITHIN THE 05Z-06Z WINDOW...BEST POTENTIAL FOR GUSTS 35 KNOTS OR SLIGHTLY HIGHER WITH AND IMMEDIATELY BEHIND THIS FRONT /05Z-08Z/. A RENEWED PEAK IN GUSTS IN EXCESS OF 30 KNOTS AS DAYTIME MIXING DEEPENS LATE MORNING INTO THE AFTERNOON THURSDAY. //DTW THRESHOLD PROBABILITIES... * HIGH FOR CEILING BELOW 5000 FT THROUGH THURSDAY. * LOW FOR EXCEEDING CROSSWIND THRESHOLD AROUND 250 DEGREES TONIGHT AND THURSDAY. && .PREV DISCUSSION...ISSUED 923 PM EDT WED OCT 28 2015 UPDATE... DYNAMIC CLOSED MID LEVEL SYSTEM AND ACCOMPANYING COLD FRONTAL STRUCTURE POSITIONED ALONG THE LEAD EDGE OF THE PRONOUNCED INBOUND HEIGHT FALLS ON SCHEDULE TO RAPIDLY MOVE INTO LOWER MICHIGAN DURING THE EARLY MORNING PERIOD. COLD FRONTAL TIMING LOCALLY STILL CENTERED 05Z-07Z. NARROW BUT STOUT AXIS OF ASCENT ALONG THIS FEATURE CURRENTLY ANCHORING A LINE OF CONVECTIVE SHOWERS OVER THE EASTERN SHORES OF LAKE MICHIGAN. STRONGEST WIND GUSTS SEEMINGLY TIED TO ANY CONVECTIVE ACTIVITY...NOTING A BROADER SPECTRUM OF GUSTS WITHIN THE 30 TO 35 KNOT RANGE ACCOMPANYING THIS PRECIPITATION. ALSO ACKNOWLEDGING THE PEAK GUSTS AT AURORA AND MIDWAY AIRPORT IN NE IL /45 AND 41 KNOTS/ WITH A TRAILING CELL EMBEDDED WITHIN THE BULLSEYE OF RAPIDLY INCREASING POST-FRONTAL ISENTROPIC DESCENT...THERE WILL REMAIN A WINDOW FOR SOME LOCALIZED HIGHER END GUSTS /40+ KNOTS/ TO EMERGE IF AUGMENTED BY CONVECTION. ABSENT OF THIS...GUSTS INTO THE 30 TO 35 KNOT RANGE POST-FRONTAL REMAIN A SOLID CALL...WITH NEITHER UPSTREAM OBSERVATIONS OR RECENT HRRR/RAP/NAM GUIDANCE PROVIDING SUPPORTING EVIDENCE FOR SEEING AN ADVISORY WORTHY WIND EVENT TONIGHT. SIMPLY MINOR/COSMETIC TWEAKS TO THE GOING FORECAST WITH THE EVENING UPDATE. PREV DISCUSSION...ISSUED 337 PM EDT WED OCT 28 2015 SHORT TERM...THROUGH TONIGHT A STRONG AND STRENGTHENING LOW PRESSURE SYSTEM OVER THE WESTERN U.P. WILL CONTINUE NORTH INTO ONTARIO TONIGHT PULLING A COLD FRONT THROUGH LOWER MI AFTER MIDNIGHT. MEANWHILE...A DEEPENING MID LEVEL LOW WILL SURGE SOUTHWARD THROUGH THE NORTHERN PLAINS INTO THE BASE OF THE LONGWAVE TROUGH...REACHING THE GREAT LAKES BY THURSDAY MORNING. THIS PAIR OF SYSTEMS WILL RESULT IN STRONG WINDS OVERNIGHT AND INTO THURSDAY AS WELL AS A CONTINUED CHANCE OF RAIN SHOWERS. A MINIMAL THREAT OF THUNDER EXISTS WITH THE COLD FRONTAL PASSAGE...BUT CANNOT BE RULED OUT. A DRY SLOT LIFTING NORTH INTO SE MI IS HELPING DECREASE THE COVERAGE OF THE STEADY RAINS THAT PERSISTED INTO THE EARLY AFTERNOON. A WEALTH OF MOISTURE NEAR THE SFC HAS RESULTED IN DZ OVER MOST OF THE AREA OUTSIDE OF THE BANDS OF ACTUAL SHOWERS. EXPECT COVERAGE TO CONTINUE TO DECREASE AS THE THETA E PLUME LIFTS NE THROUGH THE EVENING HOURS. A BAND OF SHOWERS WILL LIKELY DEVELOP ON THE COLD FRONT TONIGHT AROUND 05-09Z. MODELS SHOW LOW CAPE VALUES OF A COUPLE HUNDRED JOULES...AND SKINNY CAPE AT THAT LOCATED FROM THE SFC UP TO AROUND 8KFT. IN CONJUCTION WITH WEAK CAPE...SHOWALTER INDEX BRIEFLY DIP NEGATIVE AND COLD POOL WILL STEEPEN LL LAPSE RATES. 850MB/500MB TEMPS WILL DROP TO -5C/-30C BY THURSDAY MORNING. THUS SOME DEEPER CONVECTION COULD OCCUR...RESULTING IN AN ISOLATED RUMBLE OF THUNDER. POTENTIAL FOR STRONG WINDS TONIGHT WILL BE DISCUSSED AT THE START OF THE LONG TERM SECTION. LONG TERM...06Z TONIGHT THROUGH TUESDAY WITH REGARD TO TONIGHT`S COLD FRONT, THERE HAS BEEN NO CHANGE IN THINKING. THIS DYNAMICALLY INTENSE FEATURE WILL RACE ACROSS SOUTHEAST MICHIGAN BETWEEN 06Z AND 09Z. RAW GUIDANCE CANNOT CAPTURE WIND GUST POTENTIAL DUE TO THE FRONT`S COMPACT HORIZONTAL SCALE. HOWEVER, ARW/NMM PROGS SHOW HINTS AT SUSTAINED 20+KTS WITHIN THE FRONTAL ZONE AND RECENT HRRR RUNS ARE FINALLY CONFIRMING PREVIOUS FORECAST THINKING WITH SIMULATED WIND GUST SPEEDS IN EXCESS OF 30KTS WITH FROPA. THIS IS SUPPORTED METEOROLOGICALLY BY INSTABILITY WITHIN THE NOSE OF THE FRONT AND STRONG SUBSIDENCE/ISENTROPIC DESCENT IMMEDIATELY IN ITS WAKE. CROSS-SECTIONS REVEAL STRONG POSITIVE OMEGA VALUES ASSOCIATED WITH THESE FORCINGS BETWEEN THE SFC AND 700MB WITHIN A WIND FIELD THAT DOES TOUCH ADVISORY STRENGTH WINDS JUST BENEATH THE TOP OF THE FRONTAL ZONE. THUS, WIND ADVISORY CRITERIA WIND GUSTS ARE A POSSIBILITY DURING FROPA, AND MAY NECESSITATE A SHORT-FUSED WIND ADVISORY, BUT CONFIDENCE IN ACHIEVING 45 MPH ISN`T THERE YET DUE TO THE MARGINAL WIND FIELD. NO HEADLINE WILL BE ISSUED THIS AFTERNOON. IT SHOULD ALSO ALSO BE NOTED THAT STRONG CONVERGENT FORCING IMMEDIATELY AHEAD OF THE FRONT WILL PROVIDE AN OPPORTUNITY FOR CONVECTIVE WIND GUSTS IN EXCESS OF 45MPH WITHIN ANY STRONGER SHOWERS. THE ENTIRE THREAT PERIOD FOR ANY ONE LOCATION SHOULD BE NO LONGER THAN ABOUT 90 MINUTES. COLD ADVECTION WILL HELP TRANSPORT SOUTHWEST WINDS OF AT LEAST 30 KTS TO THE SURFACE THROUGH LATE MORNING THURSDAY. CAA WILL QUICKLY EASE, HOWEVER, AS THERE IS NOT MUCH COLD AIR ASSOCIATED WITH THIS SYSTEM. BY AFTERNOON, FORCING WILL TRANSITION TO MORE OF A PURE THERMAL MIXING PROCESS AND MIXING EFFICIENCY WILL CORRESPONDINGLY DECREASE. THUS, A GRADUAL DOWNWARD TREND IN WIND GUSTS IS EXPETED THROUGH THURS AFTERNOON. ALSO, A MODEST LAKE EFFECT RESPONSE WILL ENHANCE EXISTING CLOUD COVER, WHICH WILL GRADUALLY ENGULF THE ENTIRE CWA AS MOIST CYCLONIC FLOW WRAPS INTO THE AREA. THIS WILL ALSO FOSTER A FAVORABLE ENVIRONMENT FOR SCATTERS RAIN SHOWERS, PERHAPS WITH SOME LAKE ENHANCEMENT ACROSS NORTHWESTERN AREAS. A FEW SNOWFLAKES COULD SURVIVE THE JOURNEY TO THE SURFACE WITHIN HEAVIER SHOWERS NORTH OF PONTIAC, BUT THERE WILL BE NO ACCUMULATION. NO COMPLAINTS WITH 12Z GUIDANCE SUGGESTING LOWS IN THE 30S THURSDAY NIGHT. THE GRADIENT WILL EASE BY THIS TIME, BUT EXTENSIVE CLOUDS WILL MAINTAIN A HIGH FLOOR ON LOW TEMP POTENTIAL. STRATUS WILL LINGER INTO FRIDAY MORNING BEFORE CLEARING AS HIGH PRESSURE BUILDS IN. MODEST RECOVERY IN THE THERMAL FIELD BY THIS TIME WITH HIGHS NEAR 50 UNDER DECREASING CLOUDS. MOISTURE TRANSPORT INTO THE GREAT LAKES REGION ON THE BACKSIDE OF DEPARTING SURFACE HIGH AND AHEAD OF PROGRESSIVE NORTHERN STREAM TROUGH SATURDAY. INTERMODEL CONTINUITY HAS INCREASED WITH THIS FEATURE ENOUGH FOR LIKELY POPS FOR THE TRI-CITIES SATURDAY /CHANCE ELSEWHERE/ AND LIKELY AREAWIDE SATURDAY NIGHT. NO REAL COLD AIR OF NOTE WITH THIS TROUGH AS IT DEAMPLIFIES...AND UPPER HEIGHT RISES SUNDAY WILL LEAD TO A WARMER DAY. STILL SOME UNCERTAINTY WITH PROGRESSION OF SOUTHERN STREAM CUTOFF LOW AS IT EJECTS NORTHEASTWARD TOWARD THE GREAT LAKES REGION IN THE SUNDAY NIGHT/MONDAY TIMEFRAME...BUT CURRENT MODEL CONSENSUS FAVORS KEEPING THIS WAVE AND ASSOCIATED PRECIP TO OUR SOUTH. CURRENT INDICATIONS ARE THAT THE UPPER AIR PATTERN WILL EVOLVE INTO A TROUGH WEST CONUS/RIDGE EAST CONUS PATTERN...KEEPING US VERY MILD FOR THIS TIME OF YEAR INTO EARLY NOVEMBER. MARINE... PERIODS OF SOUTHEAST GALES TODAY WILL SUBSIDE THIS EVENING. SEVERAL HOURS OF DOWNTIME IS EXPECTED THIS EVENING...BUT GALE WARNINGS WILL REMAIN IN EFFECT DURING THIS TIME. SOUTHWEST WINDS WILL QUICKLY RAMP UP AFTER MIDNIGHT AS A STRONG COLD FRONT TRAVERSES THE WATERS. GUSTS TO STRONG GALES MAY BE OBSERVED OVER CENTRAL LAKE HURON. GALES WILL CONTINUE ACROSS THE WATERS THROUGH THURSDAY. SIGNIFICANT WAVE HEIGHTS WILL PEAK LATE THURSDAY MORNING OR EARLY AFTERNOON AROUND 10 FEET OVER CENTRAL LAKE HURON. MAXIMUM WAVE HEIGHTS WILL TOP OUT AROUND 15 FEET. OFFSHORE FLOW WILL MINIMIZE WAVE DEVELOPMENT IN THE NEARSHORE ZONES. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...GALE WARNING UNTIL 10 PM EDT THURSDAY FOR LHZ361>363-462-463. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LHZ422. GALE WARNING UNTIL 6 PM EDT THURSDAY FOR LHZ422. GALE WARNING UNTIL 8 PM EDT THURSDAY FOR LHZ421-441>443-464. LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LCZ460. GALE WARNING UNTIL 6 PM EDT THURSDAY FOR LCZ460. MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LEZ444. GALE WARNING UNTIL 6 PM EDT THURSDAY FOR LEZ444. LOW WATER ADVISORY FROM 3 AM TO 10 PM EDT THURSDAY FOR LEZ444. && $$ AVIATION.....MR UPDATE.......MR SHORT TERM...DRK LONG TERM....JVC/DT MARINE.......JVC YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1013 PM EDT WED OCT 28 2015 LATEST UPDATE... UPDATE/MARINE .SYNOPSIS... ISSUED AT 325 PM EDT WED OCT 28 2015 WET AND WINDY WEATHER WILL CONTINUE OVER THE NEXT 24 HOURS. THE WINDS COULD GUST AS HIGH AS 40 MPH TONIGHT INTO THURSDAY MORNING AS THE RAIN SHOWERS REMAIN PERSISTENT. A FEW LAKE EFFECT SHOWERS MAY CONTINUE NEAR THE LAKESHORE THURSDAY NIGHT...ELSEWHERE IT WILL DRY OUT...WITH THE WIND DIMINISHING. AFTER A DRY FRIDAY THE NEXT CHANCE OF RAIN ARRIVES LATE FRIDAY NIGHT INTO SATURDAY. THE AREA SHOULD DRY OUT AGAIN BY SUNDAY...BUT ANOTHER CHANCE OF LIGHT RAIN SHOULD RETURN BY TUESDAY. AFTER A COOL PERIOD THURSDAY THROUGH SATURDAY...WE SHOULD WARM TO 60 TO 65 FOR THE FIRST PART OF NEXT WEEK. && .UPDATE... ISSUED AT 1013 PM EDT WED OCT 28 2015 DID A QUICK UPDATE THIS EVENING TO TOUCH UP WIND GUSTS AND CHANCES FOR PRECIPITATION. THE COLD FRONT STRETCHES NORTH/SOUTH ALONG HIGHWAY 131...PLOWING OFF TO THE EAST FAIRLY RAPIDLY. WIND GUSTS OF 40+ MPH HAVE OCCURRED WITH THE INITIAL LINE OF SHOWERS LOCATED ALONG THE FRONT. IT WILL REMAIN WINDY THROUGH THE NIGHT AS A TIGHT PRESSURE GRADIENT WILL NOW REMAIN IN PLACE RIGHT INTO THURSDAY MIDDAY. 15 TO 30 MPH WILL BE COMMON FOR SUSTAINED WINDS INTO THURSDAY AFTERNOON WITH 30 TO 40 MPH GUSTS. A FEW POWER OUTAGES HAVE SHOWN UP ON THE CONSUMERS PAGE ALONG THE LAKESHORE AND WILL NOT BE SURPRISED TO SEE A FEW MORE AS GUSTS OF THIS MAGNITUDE BRING DOWN DEAD LIMBS ONTO POWER LINES. AS FOR THE PRECIP HAVE 80+ PCT POPS ALONG THE LAKESHORE AS LAKE EFFECT PRECIP GENERATION WILL ROLL INTO FULL SWING. DELTA T/S BY MORNING WILL BE AROUND 18C WITH A LAKE TEMP OF 13C AND 850MB TEMPS AROUND -5C. HAVE OPTED TO THROW IN THE MENTION OF RAIN AND SNOW SHOWERS IN INTERIOR CENTRAL LOWER MICHIGAN AT -5C SHOULD BE COLD ENOUGH AND THE HRRR PRECIP TYPE AGREES. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 325 PM EDT WED OCT 28 2015 RAIN SHOWERS WILL CONTINUE TONIGHT INTO THURSDAY MORNING...THEN GRADUALLY DIMINISH. WINDS WILL BE QUITE STRONG ON THE BACK SIDE OF THE SYSTEM TONIGHT INTO THE FIRST HALF OF THURSDAY. THE UPPER LOW WILL SWING THROUGH THE REGION LATE TONIGHT. A STRONG VORT COMES IN WITH IT SUPPLYING LIFT...SO THE PCPN COVERAGE SHOULD ONLY INCREASE OVERNIGHT INTO EARLY THURSDAY MORNING. ALONG WITH THE SYNOPTIC FEATURE...WE WILL ALSO SEE H8 TEMPS PLUNGE OVERNIGHT. THIS WILL HELP PRODUCE LAKE ENHANCED SHOWERS...ESPECIALLY AFTER MIDNIGHT. BOTTOM LINE...WE WILL STAY WET. THE SHOWERS WILL DIMINISH THROUGH THURSDAY AFTERNOON AS THE LOW DRIFTS AWAY AND THE DEEPER MOISTURE EXITS. IT WILL BE A CHILLY AND RAW THURSDAY. HIGHS WILL ONLY BE 45 TO 50 WITH A STRONG WIND. BORDERLINE WIND ADVISORY CONDITIONS FOR THE LAKESHORE...BUT WILL NOT ISSUE ONE AT THIS POINT AND STILL HIGHLIGHT 40 MPH GUSTS...AND 35 MPH INLAND. THE HIGHER WINDS KICK IN TONIGHT AND CONTINUE THURSDAY MORNING...BEFORE DIMINISHING THURSDAY AFTERNOON/EVENING. ANTICYCLONIC FLOW MOVES IN LATE THURSDAY NIGHT WHEN THE LAKE EFFECT WILL FINALLY END. SOME CLEARING...ESPECIALLY INLAND...WILL RESULT IN 30S FOR LOWS. DRY FOR FRIDAY WITH SURFACE HIGH PRESSURE MOVING ACROSS THE OHIO VALLEY. SOUTHERLY FLOW FRIDAY NIGHT WILL BRING A QUICK RETURN OF GULF MOISTURE. MUCH OF THE AREA SHOULD REMAIN DRY FRIDAY NIGHT...BUT SOME RAIN SHOWERS COULD RETURN OVER THE NW CWA LATE. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 325 PM EDT WED OCT 28 2015 THE MID LEVEL LOW DEVELOPING OVER THE SOUTHWEST U.S. IS FORECASTED TO OPEN UP AS IS TRACKS EASTWARD THROUGH THE ROCKIES. SOME OF IT/S ENERGY LIFTS NORTHEAST TOWARD THE GREAT LAKES REGION ON SATURDAY. A LOW LEVEL JET STRENGTHENS OVER THE PLAINS ON SATURDAY AS A RESULT OF THIS APPROACHING SYSTEM ON FRIDAY. THIS FEATURE WILL HELP TO ADVECT IN AN UNSEASONABLY MOIST AIR MASS INTO LOWER MICHIGAN AHEAD OF THE MID LEVEL WAVE. SHOWERS ARE EXPECTED TO ARRIVE SATURDAY... ESPECIALLY IN THE AFTERNOON FROM THE SOUTHWEST. THESE SHOWERS WILL THEN LINGER INTO SATURDAY NIGHT. I LEFT THUNDER OUT OF THE FORECAST DESPITE SOME INSTABILITY NEARING THE MI/IN BORDER SATURDAY AFTERNOON. IT SHOULD BE WINDY SATURDAY INTO SATURDAY NIGHT AS THE LOW LEVEL JET MOVES IN. THE MID LEVEL FLOW TURNS ZONAL BEHIND THIS DEPARTING WAVE. THIS MEANS A WARM UP FOR THE GREAT LAKES REGION. THE MONDAY THROUGH WEDNESDAY PERIOD SHOULD END UP WITH WELL ABOVE NORMAL TEMPERATURES. THERE COULD BE SOME CLOUDS AROUND...WHICH MAY OFFSET THE DAILY MAX TEMPERATURES. THUS I KEPT VALUES IN THE 60S. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 816 PM EDT WED OCT 28 2015 THE MAIN AVIATION IMPACT THE NEXT 24 HOURS...BY FAR...WILL BE THE WIND. STRONG WEST-SOUTHWEST WINDS OF 15-30 KNOTS CAN BE EXPECTED RIGHT THROUGH THE FORECAST PERIOD. WINDS WILL PEAK LATE TONIGHT AND THURSDAY MORNING...BETWEEN 09Z AND 18Z. SPEEDS DURING THAT TIME WILL BE MORE ON THE ORDER OF 20-30 KNOTS WITH GUSTS TO 30-40 KNOTS. MVFR WILL BE THE PREVALENT CATEGORY THE NEXT 24 HOURS AS LOWER CLOUDS HANG IN ACROSS THE AREA. THERE IS SOME INDICATION THAT CEILINGS MAY LIFT FOR A TIME TO VFR LATER TONIGHT...BUT NOT CONFIDENT IN THAT SCENARIO JUST YET. SHOWERS WILL BE SCATTERED WITH MAINLY VFR VSBYS...BUT SOME WIDESPREAD LAKE EFFECT RAIN IS FORECAST FOR THURSDAY MORNING. THIS WILL LIKELY LEAD TO MVFR VSBYS AT KMKG AND KGRR. && .MARINE... ISSUED AT 1013 PM EDT WED OCT 28 2015 ENDED THE SMALL CRAFT ADVISORY WITH THE GALE WARNING THE ONLY HEADLINE OUT NOW. GALES ARE NOW OCCURRING ALONG THE COAST WITH GUSTS AT THE MOMENT IN THE 35-40 KNOT RANGE. WAVES SHOULD PEAK THURSDAY MORNING IN THE 10-15 FOOT RANGE. MANY OF THE NEARSHORE BUOYS...SOUTH HAVEN...BRIDGMAN AND PORT SHELDON WERE PULLED FOR THE SEASON IN THE LAST FEW DAYS. MID LAKE BUOY CURRENTLY HAS 7 FOOTERS AND THAT SHOULD CONTINUE TO BUILD. && .HYDROLOGY... ISSUED AT 108 PM EDT WED OCT 28 2015 RAINFALL OVERNIGHT THROUGH THIS MORNING WHICH WAS NOT EXPECTED TO HAVE MUCH IMPACT ANYWAY HAS UNDERPERFORMED THUS FAR. TOTALS HAVE MOSTLY BEEN BETWEEN 0.25 AND 0.75 INCHES...WITH THE HIGHER END TOTALS CONFINED TO JACKSON COUNTY. THE GRAND RIVER AT JACKSON DID SPIKE TO 10.15 FEET THIS MORNING...BUT HAS FALLEN SINCE. BANKFULL IS 13 FEET. AN ADDITIONAL QUARTER TO HALF INCH OF RAIN IS POSSIBLE NOW THROUGH THURSDAY EVENING FROM SCATTERED LAKE ENHANCED SHOWERS. THIS DOES NOT POSE A SIGNIFICANT FLOODING RISK. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...GALE WARNING UNTIL 5 PM EDT THURSDAY FOR LMZ844>849. && $$ UPDATE...DUKE SYNOPSIS...JK SHORT TERM...JK LONG TERM...MJS AVIATION...DUKE HYDROLOGY...EBW MARINE...DUKE
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
923 PM EDT WED OCT 28 2015 .UPDATE... DYNAMIC CLOSED MID LEVEL SYSTEM AND ACCOMPANYING COLD FRONTAL STRUCTURE POSITIONED ALONG THE LEAD EDGE OF THE PRONOUNCED INBOUND HEIGHT FALLS ON SCHEDULE TO RAPIDLY MOVE INTO LOWER MICHIGAN DURING THE EARLY MORNING PERIOD. COLD FRONTAL TIMING LOCALLY STILL CENTERED 05Z-07Z. NARROW BUT STOUT AXIS OF ASCENT ALONG THIS FEATURE CURRENTLY ANCHORING A LINE OF CONVECTIVE SHOWERS OVER THE EASTERN SHORES OF LAKE MICHIGAN. STRONGEST WIND GUSTS SEEMINGLY TIED TO ANY CONVECTIVE ACTIVITY...NOTING A BROADER SPECTRUM OF GUSTS WITHIN THE 30 TO 35 KNOT RANGE ACCOMPANYING THIS PRECIPITATION. ALSO ACKNOWLEDGING THE PEAK GUSTS AT AURORA AND MIDWAY AIRPORT IN NE IL /45 AND 41 KNOTS/ WITH A TRAILING CELL EMBEDDED WITHIN THE BULLSEYE OF RAPIDLY INCREASING POST-FRONTAL ISENTROPIC DESCENT...THERE WILL REMAIN A WINDOW FOR SOME LOCALIZED HIGHER END GUSTS /40+ KNOTS/ TO EMERGE IF AUGMENTED BY CONVECTION. ABSENT OF THIS...GUSTS INTO THE 30 TO 35 KNOT RANGE POST-FRONTAL REMAIN A SOLID CALL...WITH NEITHER UPSTREAM OBSERVATIONS OR RECENT HRRR/RAP/NAM GUIDANCE PROVIDING SUPPORTING EVIDENCE FOR SEEING AN ADVISORY WORTHY WIND EVENT TONIGHT. SIMPLY MINOR/COSMETIC TWEAKS TO THE GOING FORECAST WITH THE EVENING UPDATE. && .AVIATION...ISSUED 742 PM EDT WED OCT 28 2015 MODESTLY GUSTY SOUTHWEST WINDS WILL CONTINUE PRIOR TO MIDNIGHT IN ADVANCE OF A STRONG COLD FRONT. LOCAL AND UPSTREAM OBSERVATIONS INDICATE GUST POTENTIAL OUTSIDE OF ANY SHOWERS HOVERING IN THE 20 TO 25 KNOT RANGE DURING THIS TIME. ANY ADDITIONAL CONVECTIVE SHOWERS MAY PROVIDE A LOCALIZED GUST UP TO 30 KNOTS. PRE-FRONTAL ENVIRONMENT NOW CARRYING A MORE CHAOTIC CEILING GIVEN CONTINUED DEEPER BOUNDARY LAYER MIXING. HIGHER DEGREE OF VARIABILITY BETWEEN MVFR AND VFR CIGS ARE LIKELY. STRONG COLD FRONT ON SCHEDULE TO RAPIDLY MOVE ACROSS ALL TERMINALS 05Z-07Z TONIGHT. WINDOW FOR A PERIOD OF STRONGER WSW GUSTS INTO THE 35 KNOT RANGE WITH AND IMMEDIATELY BEHIND THE FRONT...HIGHER GUST POTENTIAL AUGMENTED BY ANOTHER LINE OF SHOWERS ALIGNED ALONG THIS FRONT. UPSTREAM EVIDENCE THAT THESE HIGHER GUSTS WILL CARRY A MORE LIMITED DURATION...AND WILL HIGHLIGHT WITH A TEMPO. ANOTHER PEAK IN SOUTHWESTERLY GUSTS AS BETTER MIXING ENSUES FROM MID MORNING ONWARD...AGAIN LOOKING AT HIGH END GUSTS REACHING 35 KNOTS. FOR DTW...WELL MIXED SOUTHWEST PRE-FRONTAL ENVIRONMENT WILL MAINTAIN GUSTY CONDITIONS AND MORE VARIABLE CEILING HEIGHTS /2000 TO 4000 FT/ THROUGH 05Z. COLD FRONTAL PASSAGE WITHIN THE 05Z-06Z WINDOW...BEST POTENTIAL FOR GUSTS 35 KNOTS OR SLIGHTLY HIGHER WITH AND IMMEDIATELY BEHIND THIS FRONT /05Z-08Z/. A RENEWED PEAK IN GUSTS IN EXCESS OF 30 KNOTS AS DAYTIME MIXING DEEPENS LATE MORNING INTO THE AFTERNOON THURSDAY. //DTW THRESHOLD PROBABILITIES... * HIGH FOR CEILING BELOW 5000 FT THROUGH THURSDAY. * LOW FOR EXCEEDING CROSSWIND THRESHOLD AROUND 250 DEGREES TONIGHT AND THURSDAY. && .PREV DISCUSSION...ISSUED 337 PM EDT WED OCT 28 2015 SHORT TERM...THROUGH TONIGHT A STRONG AND STRENGTHENING LOW PRESSURE SYSTEM OVER THE WESTERN U.P. WILL CONTINUE NORTH INTO ONTARIO TONIGHT PULLING A COLD FRONT THROUGH LOWER MI AFTER MIDNIGHT. MEANWHILE...A DEEPENING MID LEVEL LOW WILL SURGE SOUTHWARD THROUGH THE NORTHERN PLAINS INTO THE BASE OF THE LONGWAVE TROUGH...REACHING THE GREAT LAKES BY THURSDAY MORNING. THIS PAIR OF SYSTEMS WILL RESULT IN STRONG WINDS OVERNIGHT AND INTO THURSDAY AS WELL AS A CONTINUED CHANCE OF RAIN SHOWERS. A MINIMAL THREAT OF THUNDER EXISTS WITH THE COLD FRONTAL PASSAGE...BUT CANNOT BE RULED OUT. A DRY SLOT LIFTING NORTH INTO SE MI IS HELPING DECREASE THE COVERAGE OF THE STEADY RAINS THAT PERSISTED INTO THE EARLY AFTERNOON. A WEALTH OF MOISTURE NEAR THE SFC HAS RESULTED IN DZ OVER MOST OF THE AREA OUTSIDE OF THE BANDS OF ACTUAL SHOWERS. EXPECT COVERAGE TO CONTINUE TO DECREASE AS THE THETA E PLUME LIFTS NE THROUGH THE EVENING HOURS. A BAND OF SHOWERS WILL LIKELY DEVELOP ON THE COLD FRONT TONIGHT AROUND 05-09Z. MODELS SHOW LOW CAPE VALUES OF A COUPLE HUNDRED JOULES...AND SKINNY CAPE AT THAT LOCATED FROM THE SFC UP TO AROUND 8KFT. IN CONJUCTION WITH WEAK CAPE...SHOWALTER INDEX BRIEFLY DIP NEGATIVE AND COLD POOL WILL STEEPEN LL LAPSE RATES. 850MB/500MB TEMPS WILL DROP TO -5C/-30C BY THURSDAY MORNING. THUS SOME DEEPER CONVECTION COULD OCCUR...RESULTING IN AN ISOLATED RUMBLE OF THUNDER. POTENTIAL FOR STRONG WINDS TONIGHT WILL BE DISCUSSED AT THE START OF THE LONG TERM SECTION. LONG TERM...06Z TONIGHT THROUGH TUESDAY WITH REGARD TO TONIGHT`S COLD FRONT, THERE HAS BEEN NO CHANGE IN THINKING. THIS DYNAMICALLY INTENSE FEATURE WILL RACE ACROSS SOUTHEAST MICHIGAN BETWEEN 06Z AND 09Z. RAW GUIDANCE CANNOT CAPTURE WIND GUST POTENTIAL DUE TO THE FRONT`S COMPACT HORIZONTAL SCALE. HOWEVER, ARW/NMM PROGS SHOW HINTS AT SUSTAINED 20+KTS WITHIN THE FRONTAL ZONE AND RECENT HRRR RUNS ARE FINALLY CONFIRMING PREVIOUS FORECAST THINKING WITH SIMULATED WIND GUST SPEEDS IN EXCESS OF 30KTS WITH FROPA. THIS IS SUPPORTED METEOROLOGICALLY BY INSTABILITY WITHIN THE NOSE OF THE FRONT AND STRONG SUBSIDENCE/ISENTROPIC DESCENT IMMEDIATELY IN ITS WAKE. CROSS-SECTIONS REVEAL STRONG POSITIVE OMEGA VALUES ASSOCIATED WITH THESE FORCINGS BETWEEN THE SFC AND 700MB WITHIN A WIND FIELD THAT DOES TOUCH ADVISORY STRENGTH WINDS JUST BENEATH THE TOP OF THE FRONTAL ZONE. THUS, WIND ADVISORY CRITERIA WIND GUSTS ARE A POSSIBILITY DURING FROPA, AND MAY NECESSITATE A SHORT-FUSED WIND ADVISORY, BUT CONFIDENCE IN ACHIEVING 45 MPH ISN`T THERE YET DUE TO THE MARGINAL WIND FIELD. NO HEADLINE WILL BE ISSUED THIS AFTERNOON. IT SHOULD ALSO ALSO BE NOTED THAT STRONG CONVERGENT FORCING IMMEDIATELY AHEAD OF THE FRONT WILL PROVIDE AN OPPORTUNITY FOR CONVECTIVE WIND GUSTS IN EXCESS OF 45MPH WITHIN ANY STRONGER SHOWERS. THE ENTIRE THREAT PERIOD FOR ANY ONE LOCATION SHOULD BE NO LONGER THAN ABOUT 90 MINUTES. COLD ADVECTION WILL HELP TRANSPORT SOUTHWEST WINDS OF AT LEAST 30 KTS TO THE SURFACE THROUGH LATE MORNING THURSDAY. CAA WILL QUICKLY EASE, HOWEVER, AS THERE IS NOT MUCH COLD AIR ASSOCIATED WITH THIS SYSTEM. BY AFTERNOON, FORCING WILL TRANSITION TO MORE OF A PURE THERMAL MIXING PROCESS AND MIXING EFFICIENCY WILL CORRESPONDINGLY DECREASE. THUS, A GRADUAL DOWNWARD TREND IN WIND GUSTS IS EXPETED THROUGH THURS AFTERNOON. ALSO, A MODEST LAKE EFFECT RESPONSE WILL ENHANCE EXISTING CLOUD COVER, WHICH WILL GRADUALLY ENGULF THE ENTIRE CWA AS MOIST CYCLONIC FLOW WRAPS INTO THE AREA. THIS WILL ALSO FOSTER A FAVORABLE ENVIRONMENT FOR SCATTERS RAIN SHOWERS, PERHAPS WITH SOME LAKE ENHANCEMENT ACROSS NORTHWESTERN AREAS. A FEW SNOWFLAKES COULD SURVIVE THE JOURNEY TO THE SURFACE WITHIN HEAVIER SHOWERS NORTH OF PONTIAC, BUT THERE WILL BE NO ACCUMULATION. NO COMPLAINTS WITH 12Z GUIDANCE SUGGESTING LOWS IN THE 30S THURSDAY NIGHT. THE GRADIENT WILL EASE BY THIS TIME, BUT EXTENSIVE CLOUDS WILL MAINTAIN A HIGH FLOOR ON LOW TEMP POTENTIAL. STRATUS WILL LINGER INTO FRIDAY MORNING BEFORE CLEARING AS HIGH PRESSURE BUILDS IN. MODEST RECOVERY IN THE THERMAL FIELD BY THIS TIME WITH HIGHS NEAR 50 UNDER DECREASING CLOUDS. MOISTURE TRANSPORT INTO THE GREAT LAKES REGION ON THE BACKSIDE OF DEPARTING SURFACE HIGH AND AHEAD OF PROGRESSIVE NORTHERN STREAM TROUGH SATURDAY. INTERMODEL CONTINUITY HAS INCREASED WITH THIS FEATURE ENOUGH FOR LIKELY POPS FOR THE TRI-CITIES SATURDAY /CHANCE ELSEWHERE/ AND LIKELY AREAWIDE SATURDAY NIGHT. NO REAL COLD AIR OF NOTE WITH THIS TROUGH AS IT DEAMPLIFIES...AND UPPER HEIGHT RISES SUNDAY WILL LEAD TO A WARMER DAY. STILL SOME UNCERTAINTY WITH PROGRESSION OF SOUTHERN STREAM CUTOFF LOW AS IT EJECTS NORTHEASTWARD TOWARD THE GREAT LAKES REGION IN THE SUNDAY NIGHT/MONDAY TIMEFRAME...BUT CURRENT MODEL CONSENSUS FAVORS KEEPING THIS WAVE AND ASSOCIATED PRECIP TO OUR SOUTH. CURRENT INDICATIONS ARE THAT THE UPPER AIR PATTERN WILL EVOLVE INTO A TROUGH WEST CONUS/RIDGE EAST CONUS PATTERN...KEEPING US VERY MILD FOR THIS TIME OF YEAR INTO EARLY NOVEMBER. MARINE... PERIODS OF SOUTHEAST GALES TODAY WILL SUBSIDE THIS EVENING. SEVERAL HOURS OF DOWNTIME IS EXPECTED THIS EVENING...BUT GALE WARNINGS WILL REMAIN IN EFFECT DURING THIS TIME. SOUTHWEST WINDS WILL QUICKLY RAMP UP AFTER MIDNIGHT AS A STRONG COLD FRONT TRAVERSES THE WATERS. GUSTS TO STRONG GALES MAY BE OBSERVED OVER CENTRAL LAKE HURON. GALES WILL CONTINUE ACROSS THE WATERS THROUGH THURSDAY. SIGNIFICANT WAVE HEIGHTS WILL PEAK LATE THURSDAY MORNING OR EARLY AFTERNOON AROUND 10 FEET OVER CENTRAL LAKE HURON. MAXIMUM WAVE HEIGHTS WILL TOP OUT AROUND 15 FEET. OFFSHORE FLOW WILL MINIMIZE WAVE DEVELOPMENT IN THE NEARSHORE ZONES. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...GALE WARNING UNTIL 10 PM EDT THURSDAY FOR LHZ361>363-462-463. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LHZ422. GALE WARNING UNTIL 6 PM EDT THURSDAY FOR LHZ422. GALE WARNING UNTIL 8 PM EDT THURSDAY FOR LHZ421-441>443-464. LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LCZ460. GALE WARNING UNTIL 6 PM EDT THURSDAY FOR LCZ460. MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LEZ444. GALE WARNING UNTIL 6 PM EDT THURSDAY FOR LEZ444. && $$ UPDATE.......MR AVIATION.....MR SHORT TERM...DRK LONG TERM....JVC/DT MARINE.......JVC YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
742 PM EDT WED OCT 28 2015 .AVIATION... MODESTLY GUSTY SOUTHWEST WINDS WILL CONTINUE PRIOR TO MIDNIGHT IN ADVANCE OF A STRONG COLD FRONT. LOCAL AND UPSTREAM OBSERVATIONS INDICATE GUST POTENTIAL OUTSIDE OF ANY SHOWERS HOVERING IN THE 20 TO 25 KNOT RANGE DURING THIS TIME. ANY ADDITIONAL CONVECTIVE SHOWERS MAY PROVIDE A LOCALIZED GUST UP TO 30 KNOTS. PRE-FRONTAL ENVIRONMENT NOW CARRYING A MORE CHAOTIC CEILING GIVEN CONTINUED DEEPER BOUNDARY LAYER MIXING. HIGHER DEGREE OF VARIABILITY BETWEEN MVFR AND VFR CIGS ARE LIKELY. STRONG COLD FRONT ON SCHEDULE TO RAPIDLY MOVE ACROSS ALL TERMINALS 05Z-07Z TONIGHT. WINDOW FOR A PERIOD OF STRONGER WSW GUSTS INTO THE 35 KNOT RANGE WITH AND IMMEDIATELY BEHIND THE FRONT...HIGHER GUST POTENTIAL AUGMENTED BY ANOTHER LINE OF SHOWERS ALIGNED ALONG THIS FRONT. UPSTREAM EVIDENCE THAT THESE HIGHER GUSTS WILL CARRY A MORE LIMITED DURATION...AND WILL HIGHLIGHT WITH A TEMPO. ANOTHER PEAK IN SOUTHWESTERLY GUSTS AS BETTER MIXING ENSUES FROM MID MORNING ONWARD...AGAIN LOOKING AT HIGH END GUSTS REACHING 35 KNOTS. FOR DTW...WELL MIXED SOUTHWEST PRE-FRONTAL ENVIRONMENT WILL MAINTAIN GUSTY CONDITIONS AND MORE VARIABLE CEILING HEIGHTS /2000 TO 4000 FT/ THROUGH 05Z. COLD FRONTAL PASSAGE WITHIN THE 05Z-06Z WINDOW...BEST POTENTIAL FOR GUSTS 35 KNOTS OR SLIGHTLY HIGHER WITH AND IMMEDIATELY BEHIND THIS FRONT /05Z-08Z/. A RENEWED PEAK IN GUSTS IN EXCESS OF 30 KNOTS AS DAYTIME MIXING DEEPENS LATE MORNING INTO THE AFTERNOON THURSDAY. //DTW THRESHOLD PROBABILITIES... * HIGH FOR CEILING BELOW 5000 FT THROUGH THURSDAY. * LOW FOR EXCEEDING CROSSWIND THRESHOLD AROUND 250 DEGREES TONIGHT AND THURSDAY. && .PREV DISCUSSION...ISSUED 337 PM EDT WED OCT 28 2015 SHORT TERM...THROUGH TONIGHT A STRONG AND STRENGTHENING LOW PRESSURE SYSTEM OVER THE WESTERN U.P. WILL CONTINUE NORTH INTO ONTARIO TONIGHT PULLING A COLD FRONT THROUGH LOWER MI AFTER MIDNIGHT. MEANWHILE...A DEEPENING MID LEVEL LOW WILL SURGE SOUTHWARD THROUGH THE NORTHERN PLAINS INTO THE BASE OF THE LONGWAVE TROUGH...REACHING THE GREAT LAKES BY THURSDAY MORNING. THIS PAIR OF SYSTEMS WILL RESULT IN STRONG WINDS OVERNIGHT AND INTO THURSDAY AS WELL AS A CONTINUED CHANCE OF RAIN SHOWERS. A MINIMAL THREAT OF THUNDER EXISTS WITH THE COLD FRONTAL PASSAGE...BUT CANNOT BE RULED OUT. A DRY SLOT LIFTING NORTH INTO SE MI IS HELPING DECREASE THE COVERAGE OF THE STEADY RAINS THAT PERSISTED INTO THE EARLY AFTERNOON. A WEALTH OF MOISTURE NEAR THE SFC HAS RESULTED IN DZ OVER MOST OF THE AREA OUTSIDE OF THE BANDS OF ACTUAL SHOWERS. EXPECT COVERAGE TO CONTINUE TO DECREASE AS THE THETA E PLUME LIFTS NE THROUGH THE EVENING HOURS. A BAND OF SHOWERS WILL LIKELY DEVELOP ON THE COLD FRONT TONIGHT AROUND 05-09Z. MODELS SHOW LOW CAPE VALUES OF A COUPLE HUNDRED JOULES...AND SKINNY CAPE AT THAT LOCATED FROM THE SFC UP TO AROUND 8KFT. IN CONJUCTION WITH WEAK CAPE...SHOWALTER INDEX BRIEFLY DIP NEGATIVE AND COLD POOL WILL STEEPEN LL LAPSE RATES. 850MB/500MB TEMPS WILL DROP TO -5C/-30C BY THURSDAY MORNING. THUS SOME DEEPER CONVECTION COULD OCCUR...RESULTING IN AN ISOLATED RUMBLE OF THUNDER. POTENTIAL FOR STRONG WINDS TONIGHT WILL BE DISCUSSED AT THE START OF THE LONG TERM SECTION. LONG TERM...06Z TONIGHT THROUGH TUESDAY WITH REGARD TO TONIGHT`S COLD FRONT, THERE HAS BEEN NO CHANGE IN THINKING. THIS DYNAMICALLY INTENSE FEATURE WILL RACE ACROSS SOUTHEAST MICHIGAN BETWEEN 06Z AND 09Z. RAW GUIDANCE CANNOT CAPTURE WIND GUST POTENTIAL DUE TO THE FRONT`S COMPACT HORIZONTAL SCALE. HOWEVER, ARW/NMM PROGS SHOW HINTS AT SUSTAINED 20+KTS WITHIN THE FRONTAL ZONE AND RECENT HRRR RUNS ARE FINALLY CONFIRMING PREVIOUS FORECAST THINKING WITH SIMULATED WIND GUST SPEEDS IN EXCESS OF 30KTS WITH FROPA. THIS IS SUPPORTED METEOROLOGICALLY BY INSTABILITY WITHIN THE NOSE OF THE FRONT AND STRONG SUBSIDENCE/ISENTROPIC DESCENT IMMEDIATELY IN ITS WAKE. CROSS-SECTIONS REVEAL STRONG POSITIVE OMEGA VALUES ASSOCIATED WITH THESE FORCINGS BETWEEN THE SFC AND 700MB WITHIN A WIND FIELD THAT DOES TOUCH ADVISORY STRENGTH WINDS JUST BENEATH THE TOP OF THE FRONTAL ZONE. THUS, WIND ADVISORY CRITERIA WIND GUSTS ARE A POSSIBILITY DURING FROPA, AND MAY NECESSITATE A SHORT-FUSED WIND ADVISORY, BUT CONFIDENCE IN ACHIEVING 45 MPH ISN`T THERE YET DUE TO THE MARGINAL WIND FIELD. NO HEADLINE WILL BE ISSUED THIS AFTERNOON. IT SHOULD ALSO ALSO BE NOTED THAT STRONG CONVERGENT FORCING IMMEDIATELY AHEAD OF THE FRONT WILL PROVIDE AN OPPORTUNITY FOR CONVECTIVE WIND GUSTS IN EXCESS OF 45MPH WITHIN ANY STRONGER SHOWERS. THE ENTIRE THREAT PERIOD FOR ANY ONE LOCATION SHOULD BE NO LONGER THAN ABOUT 90 MINUTES. COLD ADVECTION WILL HELP TRANSPORT SOUTHWEST WINDS OF AT LEAST 30 KTS TO THE SURFACE THROUGH LATE MORNING THURSDAY. CAA WILL QUICKLY EASE, HOWEVER, AS THERE IS NOT MUCH COLD AIR ASSOCIATED WITH THIS SYSTEM. BY AFTERNOON, FORCING WILL TRANSITION TO MORE OF A PURE THERMAL MIXING PROCESS AND MIXING EFFICIENCY WILL CORRESPONDINGLY DECREASE. THUS, A GRADUAL DOWNWARD TREND IN WIND GUSTS IS EXPETED THROUGH THURS AFTERNOON. ALSO, A MODEST LAKE EFFECT RESPONSE WILL ENHANCE EXISTING CLOUD COVER, WHICH WILL GRADUALLY ENGULF THE ENTIRE CWA AS MOIST CYCLONIC FLOW WRAPS INTO THE AREA. THIS WILL ALSO FOSTER A FAVORABLE ENVIRONMENT FOR SCATTERS RAIN SHOWERS, PERHAPS WITH SOME LAKE ENHANCEMENT ACROSS NORTHWESTERN AREAS. A FEW SNOWFLAKES COULD SURVIVE THE JOURNEY TO THE SURFACE WITHIN HEAVIER SHOWERS NORTH OF PONTIAC, BUT THERE WILL BE NO ACCUMULATION. NO COMPLAINTS WITH 12Z GUIDANCE SUGGESTING LOWS IN THE 30S THURSDAY NIGHT. THE GRADIENT WILL EASE BY THIS TIME, BUT EXTENSIVE CLOUDS WILL MAINTAIN A HIGH FLOOR ON LOW TEMP POTENTIAL. STRATUS WILL LINGER INTO FRIDAY MORNING BEFORE CLEARING AS HIGH PRESSURE BUILDS IN. MODEST RECOVERY IN THE THERMAL FIELD BY THIS TIME WITH HIGHS NEAR 50 UNDER DECREASING CLOUDS. MOISTURE TRANSPORT INTO THE GREAT LAKES REGION ON THE BACKSIDE OF DEPARTING SURFACE HIGH AND AHEAD OF PROGRESSIVE NORTHERN STREAM TROUGH SATURDAY. INTERMODEL CONTINUITY HAS INCREASED WITH THIS FEATURE ENOUGH FOR LIKELY POPS FOR THE TRI-CITIES SATURDAY /CHANCE ELSEWHERE/ AND LIKELY AREAWIDE SATURDAY NIGHT. NO REAL COLD AIR OF NOTE WITH THIS TROUGH AS IT DEAMPLIFIES...AND UPPER HEIGHT RISES SUNDAY WILL LEAD TO A WARMER DAY. STILL SOME UNCERTAINTY WITH PROGRESSION OF SOUTHERN STREAM CUTOFF LOW AS IT EJECTS NORTHEASTWARD TOWARD THE GREAT LAKES REGION IN THE SUNDAY NIGHT/MONDAY TIMEFRAME...BUT CURRENT MODEL CONSENSUS FAVORS KEEPING THIS WAVE AND ASSOCIATED PRECIP TO OUR SOUTH. CURRENT INDICATIONS ARE THAT THE UPPER AIR PATTERN WILL EVOLVE INTO A TROUGH WEST CONUS/RIDGE EAST CONUS PATTERN...KEEPING US VERY MILD FOR THIS TIME OF YEAR INTO EARLY NOVEMBER. MARINE... PERIODS OF SOUTHEAST GALES TODAY WILL SUBSIDE THIS EVENING. SEVERAL HOURS OF DOWNTIME IS EXPECTED THIS EVENING...BUT GALE WARNINGS WILL REMAIN IN EFFECT DURING THIS TIME. SOUTHWEST WINDS WILL QUICKLY RAMP UP AFTER MIDNIGHT AS A STRONG COLD FRONT TRAVERSES THE WATERS. GUSTS TO STRONG GALES MAY BE OBSERVED OVER CENTRAL LAKE HURON. GALES WILL CONTINUE ACROSS THE WATERS THROUGH THURSDAY. SIGNIFICANT WAVE HEIGHTS WILL PEAK LATE THURSDAY MORNING OR EARLY AFTERNOON AROUND 10 FEET OVER CENTRAL LAKE HURON. MAXIMUM WAVE HEIGHTS WILL TOP OUT AROUND 15 FEET. OFFSHORE FLOW WILL MINIMIZE WAVE DEVELOPMENT IN THE NEARSHORE ZONES. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...GALE WARNING UNTIL 10 PM EDT THURSDAY FOR LHZ361>363-462-463. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LHZ422. GALE WARNING FROM MIDNIGHT TONIGHT TO 6 PM EDT THURSDAY FOR LHZ422. GALE WARNING UNTIL 8 PM EDT THURSDAY FOR LHZ421-441>443-464. LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LCZ460. GALE WARNING FROM MIDNIGHT TONIGHT TO 6 PM EDT THURSDAY FOR LCZ460. MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LEZ444. GALE WARNING FROM MIDNIGHT TONIGHT TO 6 PM EDT THURSDAY FOR LEZ444. && $$ AVIATION.....MR SHORT TERM...DRK LONG TERM....JVC/DT MARINE.......JVC YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
358 PM EDT TUE OCT 27 2015 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 352 PM EDT TUE OCT 27 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A COMPLEX MID/UPPER LEVEL TROUGH DEVELOPING FROM SASK/MANITOBA INTO THE WRN AND SCNTRL PLAINS WITH SEVERAL EMBEDDED SHORTWAVES. DOWNSTREAM...A RIDGE HAS BUILT INTO THE GREAT LAKES AND OHIO VALLEY. AT THE SFC...SE FLOW PREVAILED ACROSS THE UPPER GREAT LAKES BTWN HIGH PRES OVER NRN ONTARIO/WRN QUEBEC AND A TROUGH OVER THE WRN/SCNTRL PLAINS WHICH LED TO SOME UPSLOPE STRATUS/FOG AT KSAW AND KCMX EARLIER THIS MORNING. OTHERWISE...VIS SATELLITE LOOP SHOWED MID CLOUDS SPREADING ACROSS INTO WRN AND CENTRAL UPPER MI WITH PARTLY SUNNY SKIES OVER ERN UPR MI. TONIGHT AND WEDNESDAY...THE MODELS WERE IN GOOD AGREEMENT WITH A SHORTWAVE OVER THE SRN PLAINS LIFTING TOWARD THROUGH THE MID MS VALLEY AS A STRONGER SHRTWV OVER SRN SASK DROPS INTO SRN MANITOBA AND NORTH DAKOTA. A DEEPENING SFC LOW WILL ALSO LIFT TO SE WI BY 12Z WED. INCREASING SSE 800-700 MB FLOW OF 35-50 KNOTS AHEAD OF THE LOW WILL DRAW ABUNDANT MOISTURE TOWARD UPPER MI (PWAT TO AROUND 1.0 INCH) AND THIS IN COMBINATION WITH DEEP-LAYER Q-VECTOR CONV WILL ALLOW RAIN TO SPREAD ACROSS THE CWA LATE TONIGHT INTO WED MORNING. PHASING OF NRN AND SRN STREAM SHORTWAVES WILL ALLOW LONGWAVE TROUGH TO DEEPEN OVER THE CENTRAL CONUS ON WED. IN TURN...AS MID-UPPER LEVEL TROUGH DEEPENS...SFC LOW OF 995-1000MB OVER SRN WI WED MORNING WILL DEEPEN NEAR 985 MB OVER ERN LAKE SUPERIOR LATE WED. DIMINISHING ISENTROPIC ASCENT IN THE MID-LATE AFTERNOON AS SFC-850 MB LOW MOVES OVERHEAD AND Q-VECTOR DIVERGENCE SPREADS IN FM THE S-SE IN WAKE OF INITIAL SOUTHERN STREAM SHORTWAVE SHOULD ALLOW RAIN TO GRADUALLY DIMINISH FROM THE SOUTH LATE AFTERNOON TOWARD EVENING. AS RAIN DIMINISHES FROM SOUTH LATE MORNING INTO AFTERNOON STRATUS WILL LOWER AND FOG MAY FORM ESPECIALLY FOR AREAS FAVORED BY UPSLOPE E-SE FLOW AS DEWPOINTS RISE INTO UPPER 40S/LOWER 50S. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 357 PM EDT TUE OCT 27 2015 THE DEEPENING SFC LOW WILL LIKELY BE SITUATED OVER LAKE SUPERIOR AND N UPPER MI AT 00Z THURSDAY...WITH THE 500MB LOW SET UP OVER S MN. LOOKS LIKE PRECIP WILL MAINLY STAY AS RAIN...BUT THERE WILL STILL BE A SMALL CHANCE OF SNOW SHOWERS MIXING IN OVER THE INTERIOR W HALF OF UPPER MI OVERNIGHT. THE WARMER TREND OF 850MB TEMPS CONTINUES...STARTING OUT AROUND 0C OVER THE FAR W AT 00Z THURSDAY AND BOTTOMING OUT BY 12Z THURSDAY IN THE -1 TO -4C RANGE WITH SFC TEMPS NEAR OR STILL ABOVE FREEZING. COOLER AIR WITH 850MB TEMPS OF - 3 TO -5C SLIDE IN LATE THURSDAY AFTERNOON INTO THURSDAY NIGHT...ALLOWING FOR THE BEST CHANCE OF SNOW MIXING INWILL BE AS THE BULK OF PRECIP PULLS OUT OF THE AREA. ALONG WITH THE PRECIP TYPE ISSUES...STRONG WINDS WILL ALSO BE A CONCERN. WITH RAPIDLY RISING HEIGHTS BEHIND THE SFC LOW THURSDAY...EXPECT A BREEZY DAY. ESPECIALLY ACROSS THE KEWEENAW PENINUSLA AND E ALONG LAKE SUPERIOR THANKS TO THE TERRAIN AND THE FACT THAT IT/S CLOSER TO THE GREATEST PRESSURE RISESMOVING ACROSS LAKE SUPERIOR. WITH 900MB WINDS OF 40-45KTS...EXPECT NEAR SFC WINDS OF 30-40KTS. WIND ADVISORIES MAY BE NEEDED. WINDS WILL QUICKLY DIMINISH W TO E THURSDAY EVENING. LOOK FOR THE SFC RIDGE SET UP ACROSS MN AND EXTENDING DOWN THROUGH MO AND THE TN VALLEY AT 06Z FRIDAY WILL SWING ACROSS THE UPPER GREAT LAKES 12-18Z FRIDAY...BEFORE SHIFTING ACROSS THE LOWER GREAT LAKES AND CENTRAL APPALACHIANS LATE IN THE DAY. THE RESULT WILL BE TEMPORARY DRY WEATHER FRIDAY-FRIDAY EVENING. JUST HOW FAST WAA PRECIP GETS INTO THE CWA IS IN QUESTION SATURDAY. THE ECMWF IS MUCH QUICKER TO BRING BACK PRECIP AT LEAST WITH THE 27/00Z RUN INDICATING A DEEPER SHORTWAVE NEARING IN THE BROAD TROUGH SET UP ACROSS MUCH OF THE CENTRAL PART OF THE NATION. EITHER WAY...WITH 850MB TEMPS OF 0-6C AND SFC TEMPS MAINLY ABOVE FREEZING...EXPECT LIQUID PRECIP INSTEAD OF FROZEN. THE SFC LOW HANGING OUT OVER W CANADA AND THE N PLAINS AT THE END OF THE WEEKEND SHOULD CONSOLIDATE OVER THE N PLAINS MONDAY AS SW FLOW SETS UP ALOFT IN RESPONSE TO A SIGNIFICANT TROUGH SET UP ACROSS THE W HALF OF N AMERICA. EXPECT THE S LOW TO EJECT NE INTO ONTARIO ON TUESDAY. EXPECT HIGHS IN THE 50S FROM SUNDAY THROUGH TUESDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 208 PM EDT TUE OCT 27 2015 VFR CONDITIONS AT TAF SITES SHOULD CONTINUE UNDER ABUNDANT MID AND HIGH CLOUDS UNTIL ARRIVAL OF -RA FROM THE SW OVERNIGHT AHEAD OF SYSTEM LIFTING UP FROM THE CENTRAL PLAINS. CONDITIONS WILL THEN DROP TO MVFR WITH ONSET OF STEADIER RAIN LATE TONIGHT AND TO LIFR BY WEDNESDAY MORNING AS HIGHER DEWPOINT AIR WITH SYSTEM LEADS TO FORMATION OF LOW STRATUS AND FOG ACROSS THE AREA. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 352 PM EDT TUE OCT 27 2015 WINDS WILL BEGIN TO INCREASE TONIGHT AHEAD OF A STRENGTHING LOW LIFTING TOWARD THE WRN LAKES. THE LOW WILL RAPIDLY DEEPEN AS IT MOVES ACROSS THE UPPER GREAT LAKES WED AFTN/NIGHT ON ITS WAY TO JAMES BAY THU. WINDS ACROSS MUCH OF LAKE SUPERIOR WILL BE INTO THE 15-25KT RANGE BY EARLY THIS EVENING...INCREASING TO 20-30KT LATE TONIGHT. THE STRONGEST WINDS TONIGHT WILL BE FAVORED FOR CNTRL/ERN LAKE SUPERIOR...TYPICAL FOR SE FLOW. WINDS WILL TEMPORARILY DIMINISH WED AFTERNOON/EVENING AS THE LOW LIFTS OVER UPPER MI AND LAKE SUPERIOR. NW GALES WILL THEN DEVELOP BEHIND THE LOW LATE WED NIGHT THRU THU WITH THE STRONGEST WINDS TO NEAR 45KT OVER THE E HALF OF THE LAKE BY THU. WINDS WILL DIMINISH TO UNDER 20KT W TO E LATE THU NIGHT/FRI AS A HIGH PRES RIDGE BUILDS IN FROM THE WEST AND GENERALLY REMAIN AT OR BELOW 20 KTS INTO SAT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR LSZ267. GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR LSZ265-266. GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LSZ263-264. LAKE MICHIGAN... GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING FOR LMZ221-248-250. && $$ SHORT TERM...VOSS LONG TERM...KF AVIATION...VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
353 PM EDT TUE OCT 27 2015 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 352 PM EDT TUE OCT 27 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A COMPLEX MID/UPPER LEVEL TROUGH DEVELOPING FROM SASK/MANITOBA INTO THE WRN AND SCNTRL PLAINS WITH SEVERAL EMBEDDED SHORTWAVES. DOWNSTREAM...A RIDGE HAS BUILT INTO THE GREAT LAKES AND OHIO VALLEY. AT THE SFC...SE FLOW PREVAILED ACROSS THE UPPER GREAT LAKES BTWN HIGH PRES OVER NRN ONTARIO/WRN QUEBEC AND A TROUGH OVER THE WRN/SCNTRL PLAINS WHICH LED TO SOME UPSLOPE STRATUS/FOG AT KSAW AND KCMX EARLIER THIS MORNING. OTHERWISE...VIS SATELLITE LOOP SHOWED MID CLOUDS SPREADING ACROSS INTO WRN AND CENTRAL UPPER MI WITH PARTLY SUNNY SKIES OVER ERN UPR MI. TONIGHT AND WEDNESDAY...THE MODELS WERE IN GOOD AGREEMENT WITH A SHORTWAVE OVER THE SRN PLAINS LIFTING TOWARD THROUGH THE MID MS VALLEY AS A STRONGER SHRTWV OVER SRN SASK DROPS INTO SRN MANITOBA AND NORTH DAKOTA. A DEEPENING SFC LOW WILL ALSO LIFT TO SE WI BY 12Z WED. INCREASING SSE 800-700 MB FLOW OF 35-50 KNOTS AHEAD OF THE LOW WILL DRAW ABUNDANT MOISTURE TOWARD UPPER MI (PWAT TO AROUND 1.0 INCH) AND THIS IN COMBINATION WITH DEEP-LAYER Q-VECTOR CONV WILL ALLOW RAIN TO SPREAD ACROSS THE CWA LATE TONIGHT INTO WED MORNING. PHASING OF NRN AND SRN STREAM SHORTWAVES WILL ALLOW LONGWAVE TROUGH TO DEEPEN OVER THE CENTRAL CONUS ON WED. IN TURN...AS MID-UPPER LEVEL TROUGH DEEPENS...SFC LOW OF 995-1000MB OVER SRN WI WED MORNING WILL DEEPEN NEAR 985 MB OVER ERN LAKE SUPERIOR LATE WED. DIMINISHING ISENTROPIC ASCENT IN THE MID-LATE AFTERNOON AS SFC-850 MB LOW MOVES OVERHEAD AND Q-VECTOR DIVERGENCE SPREADS IN FM THE S-SE IN WAKE OF INITIAL SOUTHERN STREAM SHORTWAVE SHOULD ALLOW RAIN TO GRADUALLY DIMINISH FROM THE SOUTH LATE AFTERNOON TOWARD EVENING. AS RAIN DIMINISHES FROM SOUTH LATE MORNING INTO AFTERNOON STRATUS WILL LOWER AND FOG MAY FORM ESPECIALLY FOR AREAS FAVORED BY UPSLOPE E-SE FLOW AS DEWPOINTS RISE INTO UPPER 40S/LOWER 50S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 512 AM EDT TUE OCT 27 2015 DEEPENING LONGWAVE TROUGH OVER THE CENTRAL CONUS ON WEDNESDAY RESULTS FROM PHASING OF MANY INDIVIDUAL SHORTWAVES STRETCHING FROM BRITISH COLUMBIA THROUGH THE INTERMOUNTAIN WEST. AS TROUGH DEEPENS SFC LOW 995-1000MB DEVELOPS OVER IA/IL/SOUTHERN WI BY 12Z ON WED. MOIST ADVECTION OF PWATS OVER 1 INCH AHEAD OF H85 TROUGH AND SFC LOW ALONG WITH H85-H5 Q-VECTOR CONVERGENCE FM THE DEEPENING TROUGH SHOULD SPREAD THE RAIN CURRENTLY OVER LOWER MISSISSIPPI RIVER VALLEY ACROSS THE UPPER GREAT LAKES BY DAYBREAK ON WEDNESDAY. ISENTROPIC ASCENT 290-300K/H9-H65 ALONG WITH THE LARGER SCALE FORCING WITH SOME ADDITIONAL ASSIST TO RIGHT ENTRANCE REGION OF UPPER JET OVER ONTARIO WILL RESULT IN MODERATE RAIN OVER UPR MICHIGAN ON WEDNESDAY. AS THE ISENTROPIC ASCENT FADES IN THE MID-LATE AFTN AND Q-VECTOR DIVERGENCE SPREADS NORTH OVER CWA IN WAKE OF INITIAL SOUTHERN STREAM SHORTWAVE EXPECT RAIN TO START TO DIMINISH. MID CONUS TROUGH CLOSES OFF SHARPLY INTO THURSDAY AS INITIAL CENTRAL CONUS TROUGH MOVING EAST PHASES WITH STRONG NORTHERN STREAM TROUGH DIGGING SSE FM SASKATCHEWAN AND MANITOBA ON WEDNESDAY MORNING TO THE WESTERN GREAT LAKES WEDNESDAY NIGHT. SFC LOW LIFTING FM THE MIDDLE MISSISSIPPI RIVER VALLEY DEEPENS TO NEAR 983-985MB AS IT REACHES SOUTH CENTRAL LK SUPERIOR WEDNESDAY EVENING THEN STAYS SIMILAR STRENGTH AS IT MOVES TO FAR EAST LK SUPERIOR OR JUST EAST OF LK SUPERIOR BY 12Z THURSDAY. TREND IS SLOWER IN MAJORITY OF GUIDANCE IN LIFTING THE LOW NORTH OF THE REGION. MAIN RESULT IS MORE WIDESPREAD PRECIP LINGERING OVER MUCH OF UPR MICHIGAN WEDNESDAY NIGHT INTO THURSDAY WITH TROWAL WORKING ACROSS WEST TO EAST AS SEEN IN THETA-E FIELDS WITH HEIGHT /ESPECIALLY H7-H6/ AND H7-H5 Q-VECTOR CONVERGENCE. ALSO SEE THE SLOWER TREND SHOW UP WITH WARMER AIR IN THE SFC-H85 LAYER ORIENTED EAST TO WEST ACROSS UPR MICHIGAN AND LK SUPERIOR. BIGGEST IMPACT IS ON SNOW POTENTIAL OVER WESTERN CWA. H85 TEMPS LAST NIGHT WERE AROUND -2C AT THE WARMEST AND -5C AT THE COOLEST BUT LATEST RUNS HAVE TRENDED WARMER. GFS/NAM SOUNDINGS AT IWD INDICATE EVEN WITH H85 TEMPS AROUND -2C OR -3C/GOOD ENOUGH FOR LAKE ENHANCEMENT WITH WATER TEMPS AROUND 8C AND PLENTY OF LARGE SCALE LIFT/MOISTURE/...WET BULB ZERO HEIGHTS REMAIN AT OR ABOVE 1000 FT AGL WHICH SUGGEST A MIX OF RAIN AND SNOW...BUT NOT MUCH SNOW ACCUMULATION. WILL BE TIGHT GRADIENT BTWN WHERE SNOW IS MAIN PYPE AND WHERE THERE WILL BE MIX OR JUST RAIN. RIGHT NOW BELIEVE THAT LINE WILL STAY MAINLY WEST AND SOUTH OF WESTERN CWA. TRENDED SNOW BACK OVER WESTERN INTERIOR TO LESS THAN 0.5 INCH. COOL AND BREEZY CONDITIONS EXPECTED ON THURSDAY ALL CWA. STRONGEST WINDS WILL BE ALONG LK SUPERIOR. SOLID 40-45 MPH IN THE MIXED LAYER THOUGH SLOWER TREND WITH SFC LOW AND LACK OF STRONG COLD AIR ADVECTION WILL COMPLICATE HOW QUICKLY THE STRONG WINDS MIX TO SFC. GOOD PORTION OF THESE WINDS WILL MAKE IT TO SFC AS GUSTS. GALES LOOK CERTAIN OVER LK SUPERIOR AND PROBABLY WILL NEED WIND ADVISORY HEADLINES ON ADJACENT SHORELINES OF NORTHERN UPR MICHIGAN. MOST FAVORED LOCATIONS TO SEE STRONGEST WINDS WOULD BE COPPER HARBOR AND MUNISING/GRAND MARAIS/FAR NORTHERN LUCE COUNTY. WINDS DIMINISH BY MIDNIGHT THURSDAY NIGHT. COOLEST AIR SETTLES ACROSS LK SUPERIOR ON THURSDAY NIGHT WITH H85 TEMPS DOWN TO -6C OR -7C. SOUNDINGS AT END OF FETCH OVER EASTERN LK SUPERIOR INDICATE SHALLOW MOIST LAYER AROUND H85 AND DRY SUB CLOUD LAYER. KEPT LOW CHANCES IN FOR LAKE EFFECT WITH SUFFICIENT OVERWATER INSTABILITY...BUT DRY AIR BLO CLOUD BASE AND FLOW BECOMING MORE ANTICYLONIC SHOULD ALLOW FOR DIMINISHING TREND TO LAKE EFFECT INTO FRIDAY. EXPECT SKIES TO STAY MOSTLY CLOUDY WITH INCREASING WARM AIR ADVECTION OCCURRING ATOP SHALLOW COLD LAYER. MID CLOUDS INCREASE IN THE AFTN AHEAD OF NEXT CHANCE OF RAIN WHICH ARRIVES OVERNIGHT FRIDAY NIGHT. GFS IS NOW JOINED BY ECMWF IN SHOWING SWATH OF RAIN SPREADING OVER UPPER GREAT LAKES LATE FRIDAY NIGHT INTO AT LEAST SATURDAY MORNING AHEAD OF SHORTWAVE TROUGH CROSSING THE NORTHERN PLAINS. STRONGEST LOW-LEVEL MOISTURE ADVECTION REMAINS MORE OVER CNTRL AND LOWER GREAT LAKES...SO LIKELY WILL NOT SEE TOO HIGH AMOUNTS OVER UPR MICHIGAN /AROUND 0.10 INCH BUT LESS THAN 0.25 INCH/. HALLOWEEN 2014 HAD SNOW OVER PARTS OF UPR MICHIGAN SO AT LEAST WILL NOT BE LOOKING AT ANYTHING THAT COLD. TEMPS ON SATURDAY TOP OUT IN THE UPR 40S TO NEAR 50 DEGREES. WARMING TREND STILL EXPECTED INTO FIRST PART OF NEXT WEEK WITH ONLY SMALL CHANCES OF RAIN AS IT STANDS NOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 208 PM EDT TUE OCT 27 2015 VFR CONDITIONS AT TAF SITES SHOULD CONTINUE UNDER ABUNDANT MID AND HIGH CLOUDS UNTIL ARRIVAL OF -RA FROM THE SW OVERNIGHT AHEAD OF SYSTEM LIFTING UP FROM THE CENTRAL PLAINS. CONDITIONS WILL THEN DROP TO MVFR WITH ONSET OF STEADIER RAIN LATE TONIGHT AND TO LIFR BY WEDNESDAY MORNING AS HIGHER DEWPOINT AIR WITH SYSTEM LEADS TO FORMATION OF LOW STRATUS AND FOG ACROSS THE AREA. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 352 PM EDT TUE OCT 27 2015 WINDS WILL BEGIN TO INCREASE TONIGHT AHEAD OF A STRENGTHING LOW LIFTING TOWARD THE WRN LAKES. THE LOW WILL RAPIDLY DEEPEN AS IT MOVES ACROSS THE UPPER GREAT LAKES WED AFTN/NIGHT ON ITS WAY TO JAMES BAY THU. WINDS ACROSS MUCH OF LAKE SUPERIOR WILL BE INTO THE 15-25KT RANGE BY EARLY THIS EVENING...INCREASING TO 20-30KT LATE TONIGHT. THE STRONGEST WINDS TONIGHT WILL BE FAVORED FOR CNTRL/ERN LAKE SUPERIOR...TYPICAL FOR SE FLOW. WINDS WILL TEMPORARILY DIMINISH WED AFTERNOON/EVENING AS THE LOW LIFTS OVER UPPER MI AND LAKE SUPERIOR. NW GALES WILL THEN DEVELOP BEHIND THE LOW LATE WED NIGHT THRU THU WITH THE STRONGEST WINDS TO NEAR 45KT OVER THE E HALF OF THE LAKE BY THU. WINDS WILL DIMINISH TO UNDER 20KT W TO E LATE THU NIGHT/FRI AS A HIGH PRES RIDGE BUILDS IN FROM THE WEST AND GENERALLY REMAIN AT OR BELOW 20 KTS INTO SAT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR LSZ267. GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR LSZ265-266. GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LSZ263-264. LAKE MICHIGAN... GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING FOR LMZ221-248-250. && $$ SHORT TERM...VOSS LONG TERM...JLA AVIATION...VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
351 PM EDT TUE OCT 27 2015 .SHORT TERM...THIS EVENING AND TONIGHT HIGH CONTINUITY WITHIN THE NWP EXISTS THAT A COMPLEX WAVE MERGER EVENT WILL COMMENCE OVER THE GREAT LAKES BY EARLY THIS EVENING. THE FIRST PHASE OF THE WAVE MERGER/INTERACTION IS THE RAPID SURGE IN REMNANT HURRICANE PATRICIA MOISTURE DUE NORTHWARD INTO LOWER MICHIGAN. BULK ANALYSIS CONTINUES TO SUPPORT THAT A WAVE SEPARATION WILL EXIST BETWEEN THIS MIDLEVEL MOISTURE/PV ANOMALY AND THE MORE DOMINANT UPPER LEVEL PV ANOMALY DIGGING SOUTHWARD THROUGH ALBERTA. THERE IS IMPORTANCE IN THIS INFORMATION ON WAVE SEPARATION AS IT INCREASES CONFIDENCE THAT THE SLUG OF MIDLEVEL MOISTURE WILL KEEP PROGRESSING AND NOT STALL OUT. IF THERE HAS BEEN ONE NOTABLE TREND IT HAS BEEN FOR A SLIGHTLY SLOWER ONSET OF PRECIPITATION AND MOISTURE LIFTING NORTHWARD INTO SOUTHEASTERN MICHIGAN. A PERSISTENT LOW LEVEL EASTERLY WIND FEED WILL MAINTAIN A 12 KFT LAYER OF DRY AIR THAT WILL LIMIT ANY STRAY CHANCES AT THE FRONT END/EARLY EVENING. MUCH OF THE DETERMINISTIC SUITE AND CAMS INCLUDING SOME SUPPORT FROM HRRR 1KM REFLECTIVITY SUPPORTS HOLDING OFF PRECIPITATION SOUTH OF M 59 UNTIL 4Z THIS EVENING. THEREFORE...THE NARRATIVE BECOMES INCREASING WIDESPREAD RAIN DEVELOPING AFTER MIDNIGHT. MODELS ARE SHOWING A VERY EFFICIENT RESPONSE OF INCREASING MIDLEVEL SHEARING DEFORMATION THAT WILL FEAST ON THE AMOUNT OF REMNANT TROPICAL MOISTURE...EFFECTIVLY WRINGING OUT THE AVAILABLE MOISTURE WITHIN THE COLUMN. THERE ARE TWO SURGES OF HEAVIER RAINFALL RATES...THE FIRST LIFTING NORTHWARD THROUGH ALL AREAS PRIMARILY BETWEEN 06-09Z...THE SECOND ALIGNED NORTH TO SOUTH OVER THE FAR EASTERN CWA (WAYNE/MONROE/MACOMB/ST CLAIR/OAKLAND COUNTIES) BETWEEN 09-12Z. AGAIN...THERE IS FAIRLY HIGH CONFIDENCE IN RAINFALL AMOUNTS THROUGH 12 Z OF .70 TO .80 OF AN INCH. WITH THE ORIENTATION OF THE SECOND SURGE...HIGHEST RAIN AMOUNTS ARE EXPECTED FOR AREAS EAST OF THE IRISH HILLS/GLACIAL TERRAIN. OVERALL...THE POTENTIAL FOR THUNDER REMAINS LOW...THE THERMODYNAMIC PROFILE REMAINS A FAIRLY STABLE ONE THROUGH 10 KFT AGL. && .LONG TERM... NWP IN REMARKABLE AGREEMENT GIVEN MYRIAD MOVING PARTS INVOLVED IN A DYNAMIC SCENARIO THAT WILL PLAY OUT OVER THE NEXT 48 HOURS. LOCALLY, THE LONG TERM PERIOD WILL BEGIN WITH A CARRYOVER OF TONIGHT`S WEATHER. VERY STRONG UPPER-LEVEL DIVERGENCE WILL BE DIRECTLY OVERHEAD, BUT IN THE PROCESS OF EXITING EAST ALONG WITH THE REST OF THE FIRST WAVE OF MOISTURE AND FORCING. THE RAIN WILL MAINTAIN ITS OVERNIGHT CHARACTER THROUGH THE EARLY MORNING, BUT WILL QUICKLY WIND DOWN FROM SOUTHWEST TO NORTHEAST 12-15Z. ATTENTION THEN TURNS TO THE DEEPENING LONGWAVE TROUGH OVER THE WEST- CENTRAL UNITED STATES TODAY. WATER VAPOR REVEALS A PLETHORA OF EMBEDDED SHORTWAVES FROM MONTANA TO TEXAS. FURTHER NORTH, A WELL- DEFINED PV RIBBON IS DIVING SOUTH AND IS FORECAST TO UNDERGO RAPID AMPLIFICATION OVER THE NORTHERN PLAINS AND UPPER MIDWEST TONIGHT INTO WEDNESDAY. AS THE INITIAL MOISTURE SURGE PUSHES EAST WED MORNING, SOME CONSOLIDATION OF SAID DISTURBANCES IS FORECAST TO OCCUR, PARTICULARLY ABOVE 500MB. THE FLOW AROUND THE ASSOCIATED CONSOLIDATED H4-H3 PV ANOMALY WILL DRAW IN PLENTY OF DRY AIR AND SOUTHEAST MICHIGAN WILL SPEND THE MAJORITY OF THE DAYTIME HOURS WITHIN A DRY SLOT, ALBEIT NOT A CLASSIC ONE, AS A RESULT. CONVECTIVE SHOWERS ALONG THE CONVERGENT LEAD EDGE OF THE DRY SLOT ARE A POSSIBILITY, AND THESE COULD PRODUCE SPORADIC WIND GUSTS OF 40 TO 50 MPH. THIS THREAT, IF IT DEVELOPS, WILL BE SHORT-LIVED AS MID AND UPPER LEVEL MOISTURE WILL BE SCOURED OUT AND FRONTAL-TYPE FORCING WILL QUICKLY MOVE EAST. SEEING AS HOW THE DRY SLOT WILL REMAIN ELEVATED, ELEVATED COOLING ASSOCIATED WITH THE PASSAGE OF THIS WAVE DURING PEAK HEATING WILL LEND ITSELF AT LEAST TO SOME AFTERNOON DRIZZLE PRODUCTION IF NOT LOW-TOPPED SHOWERS GIVEN SUFFICIENT LINGERING MOISTURE DEPTH. BY THIS TIME, THE AFOREMENTIONED VERY DYNAMIC HIGH-LATITUDE WAVE WILL BE IN FIRM CONTROL OF THE LARGER SCALE CIRCULATION AND WILL BE SLAMMING INTO THE GREAT LAKES IN THE UPPER LEVELS. IT WILL TAKE ON AN INCREASINGLY NEUTRAL TILT, FORCING THE UPPER JET TO TRANSLATE RAPIDLY DOWNSTREAM FROM THE EASTERN PLAINS AT 21Z WED TO THE LOWER GREAT LAKES 12Z THURS. ELEVATED FGEN PROCESSES WILL AID THE PRODUCTION OF A SIGNIFICANT TROPOPAUSE UNDULATION AS THIS OCCURS, AND THE DEEP TROPOSPHERIC COLD FRONT WILL UNDERGO STEADY INTENSIFICATION AS THE JET-FRONT COUPLET MATURES. ALTHOUGH THE TEMPERATURE GRADIENT ACROSS THE FRONT IS NOT AT ALL IMPRESSIVE AS FAR AS AUTUMN COLD FRONTS GO, STRONG DYNAMIC FORCING AT ALL LEVELS WILL STILL CAUSE IT TO PACK A PUNCH AS IT RACES WEST-TO-EAST ACROSS SE MICHIGAN 06-09Z. COLD FROPA WILL REPRESENT THE BEST POSSIBILITY FOR HIGHER END WINDS. FIRST, THERE IS THE FRONT ITSELF. WHILE NOT EXHIBITING CLASSIC DENSITY CURRENT CHARACTERISTICS, INSTABILITY IN THE NOSE OF THE FRONTAL ZONE STILL LOOKS SUFFICIENT TO PRODUCE ENOUGH VIGOROUS MIXING AND BRIEF HIT OF WIND GUSTS AROUND WIND ADVISORY CRITERIA. IN FACT, NAM12 DEPICTIONS OF DOWNWARD MOMENTUM TRANSPORT ON THE 284K SURFACE SUGGEST 38-44KTS IS ACHIEVABLE. THIS REPRESENTS A WINDOW FOR A POTENTIAL SHORT-FUSED WIND ADVISORY BETWEEN ABOUT 05Z-10Z THURSDAY MORNING. SECOND, DEEP AND STRONG FRONTAL FORCING WILL CAUSE A LINE OF CONVECTION ALONG THE FRONT LIKEWISE CAPABLE OF MIXING DOWN SIMILARLY STRONG WINDS. COLD ADVECTION WILL FORCE STRONG SYSTEM RELATIVE ISENTROPIC ASCENT THROUGH MUCH OF THURSDAY, BUT A LACK OF ANY REAL COLD AIR BEHIND THE FRONT WILL REALLY LIMIT POTENTIAL IN THIS OTHERWISE FAVORABLE SETUP. FURTHER, THE SLOWLY DEEPENING NATURE OF THE NOW-DISTANT SURFACE CYCLONE WILL CONTRIBUTE JUST A MINIMAL ISALLOBARIC COMPONENT TO WIND GUSTS. CURRENT THINKING IS THAT, AFTER AN INITIAL POP OF WINDS WITH FROPA, POST-FRONTAL WINDS ON THURSDAY TOP OUT BELOW THE 38KT/45MPH WIND ADVISORY THRESHOLD. BETWEEN CLOUDS AND COLD ADVECTION, THURSDAY`S TEMPERATURE RESPONSE WILL BE MUTED. WENT BELOW NEARLY ALL GUIDANCE WITH MID 40S ALONG THE GLACIAL RIDGE AND UPPER 40S ELSEWHERE. SHORTWAVE UPPER RIDGING AND ASSOCIATED SURFACE HIGH BUILDING INTO THE GREAT LAKES REGION FRIDAY AS THE STRONG LOW PULLS AWAY SHOULD PROVIDE FOR A PLEASANT LATE FALL DAY...WITH DIMINISHING WINDS...MAINLY SUNNY SKIES...AND HIGHS AROUND 50. PATTERN REMAINS PROGRESSIVE THANKS TO A STRONG PACIFIC JET COMING ASHORE. THIS FLOW WILL BREAK DOWN INTO A FULL LATITUDE TROUGH...WITH 12Z SUITE CONTINUING TO ZIP THE NORTHERN PORTION OF THE TROUGH ACROSS THE NORTHERN CONUS...WHILE THE SOUTHERN PORTION CUTS OFF OVER THE SOUTHWEST US. RETURN FLOW IN ADVANCE OF THE FORMER FEATURE AND ON THE BACKSIDE OF THE DEPARTING HIGH WILL ALLOW MOISTURE TO INCREASE LOCALLY SATURDAY...WITH ACCOMPANYING RAIN CHANCES THROUGH SATURDAY NIGHT. PREDICTABILITY REMAINS LOW SUNDAY INTO NEXT WEEK WITH HOW QUICKLY THE SOUTHWEST US CUTOFF EJECTS...BROAD BRUSH LOW POPS FOR NOW WILL BE REFINED IN THE FUTURE. A FAIRLY GOOD CHANCE FOR TEMPS WELL ABOVE NORMAL AS WE TURN THE PAGE TO NOVEMBER DUE TO LACK OF COLD AIR WITH THE DEAMPLIFYING NORTHERN STREAM TROUGH AND CONTINUED WARM ADVECTION AHEAD OF THE SOUTHERN STREAM TROUGH. && .MARINE... A STRENGTHENING LOW WILL LIFT ACROSS THE WESTERN GREAT LAKES INTO CANADA BRINGING A PERIOD OF SOUTHEAST GALES TONIGHT INTO EARLY WEDNESDAY. GALE WARNINGS AND SMALL CRAFT ADVISORIES ARE IN EFFECT FOR THIS GALE EVENT. A STRONG COLD FRONT WILL RACE ACROSS THE WATERS LATE THURSDAY NIGHT BRINGING GALES...AND LOCALLY STRONG GALES...TO AREA WATERS. FOR AREAS NOT EXPECTED TO EXPERIENCE GALES TONIGHT....GALE WATCHES ARE IN EFFECT FOR THIS SECOND GALE EVENT. SIGNIFICANT WAVE HEIGHTS WILL PEAK AROUND 8 TO 11 FEET FOR BOTH EVENTS. MAXIMUM WAVE HEIGHTS OF 15 TO 20 FEET WILL POSSIBLE IN FAVORED AREAS...MAINLY THE OPEN WATERS OF CENTRAL LAKE HURON. && .AVIATION...ISSUED 213 PM EDT TUE OCT 27 2015 HIGH MIDLEVEL MOISTURE CONTENT WILL BE DRAWN NORTHWARD THIS EVENING IN ADVANCE OF A DEEPENING LOW PRESSURE SYSTEM OVER THE NORTHERN MISSISSIPPI RIVER VALLEY. AN AXIS OF THE DEEP MIDLEVEL MOISTURE IS FORECASTED TO LIFT DIRECTLY NORTHWARD THROUGH THE TERMINALS...AFFECTING THE SITES PRIMARILY BETWEEN 06-15Z. DELAYED ARRIVAL OF LOWER CIGS AND RAIN FOR THE NORTHERN TAF SITES BY AN HOUR OR TWO...OTHERWISE TIMING OFFERED BY THE PREVIOUS SET OF TAFS LOOK GOOD FOR KPTK SOUTHWARD. THERE IS A HIGH LIKLIHOOD FOR IFR CONDITIONS VERY LATE TONIGHT WITH SOME POTENTIAL FOR LIFR AT DAYBREAK. CONFIDENCE IS INCREASING THAT IFR CIGS WILL PERSIST INTO THE LATE MORNING AND POSSIBLY INTO THE EARLY AFTERNOON. EAST WINDS ARE FORECASTED TO PERSIST IN THE 10 TO 20 KNOT RANGE THROUGHOUT THE TAF FORECAST. FOR DTW...EASTERLY WIND OF 090-120 WIND AT 10 TO 20 KNOTS WILL CONTINUE THROUGH TONIGHT. LITTLE TIME REFINEMENT IN CIG/PRECIPITATION TIMING WAS NEEDED THIS ISSUANCE. CONFIDENCE REMAINS HIGH IN IFR CIGS/VSBYS LATE TONIGHT AND WEDNESDAY MORNING. CONFIDENCE IS LOW ON POTENTIAL FOR LIFR CONDITIONS. //DTW THRESHOLD PROBABILITIES... * HIGH FOR CEILING BELOW 5000 FT TONIGHT. * MEDIUM FOR EXCEEDING CROSSWIND THRESHOLD FROM 140 BY TONIGHT. * LOW TO MEDIUM FOR CEILING AOB 200 FEET DEVELOPING TOWARD 12Z WEDNESDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...GALE WARNING FROM 5 AM TO 2 PM EDT WEDNESDAY FOR LHZ361>363-462-463. GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LHZ421-422. GALE WARNING FROM 5 AM TO 11 AM EDT WEDNESDAY FOR LHZ421-441>443- 464. SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO MIDNIGHT EDT WEDNESDAY NIGHT FOR LHZ422. LAKE ST CLAIR...GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LCZ460. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT WEDNESDAY NIGHT FOR LCZ460. MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LEZ444. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT WEDNESDAY NIGHT FOR LEZ444. && $$ SHORT TERM...CB LONG TERM....JVC/DT MARINE.......JVC AVIATION.....CB YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
223 PM EDT TUE OCT 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 518 AM EDT TUE OCT 27 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A COMPLEX MID/UPPER LEVEL TROUGH DEVELOPING FROM SASK/ALBERTA INTO THE NRN ROCKIES AND WRN PLAINS WITH SEVERAL EMBEDDED SHORTWAVES. DOWNSTREAM...A RIDGE WAS BUILDING FROM THE UPPER MS VALLEY TO THE WRN GREAT LAKES. A THE SFC...SE FLOW PREVAILED THROUGH THE REGION BTWN HIGH PRES OVER NRN ONTARIO AND QUEBEC AND A TROUGH OVER THE WRN PLAINS. A BAND OF LIGHT SHOWERS OR SPRINKLES ASSOCIAED WITH WAA AND 295K ISENTROPIC LIFT NORTH OF A SFC FRONT THROUGH SRN MN. OTHERWISE...IR LOOP SHOWED MID CLOUDS SPREADING ACROSS UPPER MI WHERE AREAS OF LOW CLOUDS AND PATCHY FOG HAD ALSO DEVELOPED. TODAY...RADAR TRENDS AND SHORT RANGE MODELS SUGGEST THAT THE AREA OF LIGHT PCPN FROM N CNTRL MN INTO NW WI WILL CONTINUE TO LIFT TO THE NNE WITH ONLY A FEW SPRINKLES POSSIBLE OVER THE FAR WEST BEFORE 15Z. OTHERWISE...DRIER AIR FROM 925-850 MB MOVING IN FROM THE SOUTH COMBINED WITH LIMITED DAYTIME HEATING/MIXING SHOULD HELP SCOUR OUR THE LOWER CLOUDS THIS MORNING. HOWEVER...MID LEVEL CLOUDS WILL CONTINUE TO THICKEN. NEVERTHELESS...WAA WILL HELP PUSH HIGH TEMPS INTO THE LOWER TO MID 50S. TONIGHT...THE MODELS WERE IN GOOD AGREEMENT WITH THE CNTRL PLAINS SHORTWAVE LIFTING TOWARD IA AS A STRONGER SHRTWV OVER CNTRL SASK DROP INTO SRN MANITOBA. A DEEPENING SFC LOW WILL ALSO LIFT TO SRN WI. INCREASING SRLY 80-700 MB FLOW TO 40-50 KNOTS WILL DRAW ABUNDANT MOISTURE TOWARD UPPER MI (PWAT TO AROUND 1.0 INCH) WITH RAIN SPREADING ACROSS THE CWA LATE...MAINLY BTWN 09Z-12Z. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 512 AM EDT TUE OCT 27 2015 DEEPENING LONGWAVE TROUGH OVER THE CENTRAL CONUS ON WEDNESDAY RESULTS FROM PHASING OF MANY INDIVIDUAL SHORTWAVES STRETCHING FROM BRITISH COLUMBIA THROUGH THE INTERMOUNTAIN WEST. AS TROUGH DEEPENS SFC LOW 995-1000MB DEVELOPS OVER IA/IL/SOUTHERN WI BY 12Z ON WED. MOIST ADVECTION OF PWATS OVER 1 INCH AHEAD OF H85 TROUGH AND SFC LOW ALONG WITH H85-H5 Q-VECTOR CONVERGENCE FM THE DEEPENING TROUGH SHOULD SPREAD THE RAIN CURRENTLY OVER LOWER MISSISSIPPI RIVER VALLEY ACROSS THE UPPER GREAT LAKES BY DAYBREAK ON WEDNESDAY. ISENTROPIC ASCENT 290-300K/H9-H65 ALONG WITH THE LARGER SCALE FORCING WITH SOME ADDITIONAL ASSIST TO RIGHT ENTRANCE REGION OF UPPER JET OVER ONTARIO WILL RESULT IN MODERATE RAIN OVER UPR MICHIGAN ON WEDNESDAY. AS THE ISENTROPIC ASCENT FADES IN THE MID-LATE AFTN AND Q-VECTOR DIVERGENCE SPREADS NORTH OVER CWA IN WAKE OF INITIAL SOUTHERN STREAM SHORTWAVE EXPECT RAIN TO START TO DIMINISH. MID CONUS TROUGH CLOSES OFF SHARPLY INTO THURSDAY AS INITIAL CENTRAL CONUS TROUGH MOVING EAST PHASES WITH STRONG NORTHERN STREAM TROUGH DIGGING SSE FM SASKATCHEWAN AND MANITOBA ON WEDNESDAY MORNING TO THE WESTERN GREAT LAKES WEDNESDAY NIGHT. SFC LOW LIFTING FM THE MIDDLE MISSISSIPPI RIVER VALLEY DEEPENS TO NEAR 983-985MB AS IT REACHES SOUTH CENTRAL LK SUPERIOR WEDNESDAY EVENING THEN STAYS SIMILAR STRENGTH AS IT MOVES TO FAR EAST LK SUPERIOR OR JUST EAST OF LK SUPERIOR BY 12Z THURSDAY. TREND IS SLOWER IN MAJORITY OF GUIDANCE IN LIFTING THE LOW NORTH OF THE REGION. MAIN RESULT IS MORE WIDESPREAD PRECIP LINGERING OVER MUCH OF UPR MICHIGAN WEDNESDAY NIGHT INTO THURSDAY WITH TROWAL WORKING ACROSS WEST TO EAST AS SEEN IN THETA-E FIELDS WITH HEIGHT /ESPECIALLY H7-H6/ AND H7-H5 Q-VECTOR CONVERGENCE. ALSO SEE THE SLOWER TREND SHOW UP WITH WARMER AIR IN THE SFC-H85 LAYER ORIENTED EAST TO WEST ACROSS UPR MICHIGAN AND LK SUPERIOR. BIGGEST IMPACT IS ON SNOW POTENTIAL OVER WESTERN CWA. H85 TEMPS LAST NIGHT WERE AROUND -2C AT THE WARMEST AND -5C AT THE COOLEST BUT LATEST RUNS HAVE TRENDED WARMER. GFS/NAM SOUNDINGS AT IWD INDICATE EVEN WITH H85 TEMPS AROUND -2C OR -3C/GOOD ENOUGH FOR LAKE ENHANCEMENT WITH WATER TEMPS AROUND 8C AND PLENTY OF LARGE SCALE LIFT/MOISTURE/...WET BULB ZERO HEIGHTS REMAIN AT OR ABOVE 1000 FT AGL WHICH SUGGEST A MIX OF RAIN AND SNOW...BUT NOT MUCH SNOW ACCUMULATION. WILL BE TIGHT GRADIENT BTWN WHERE SNOW IS MAIN PYPE AND WHERE THERE WILL BE MIX OR JUST RAIN. RIGHT NOW BELIEVE THAT LINE WILL STAY MAINLY WEST AND SOUTH OF WESTERN CWA. TRENDED SNOW BACK OVER WESTERN INTERIOR TO LESS THAN 0.5 INCH. COOL AND BREEZY CONDITIONS EXPECTED ON THURSDAY ALL CWA. STRONGEST WINDS WILL BE ALONG LK SUPERIOR. SOLID 40-45 MPH IN THE MIXED LAYER THOUGH SLOWER TREND WITH SFC LOW AND LACK OF STRONG COLD AIR ADVECTION WILL COMPLICATE HOW QUICKLY THE STRONG WINDS MIX TO SFC. GOOD PORTION OF THESE WINDS WILL MAKE IT TO SFC AS GUSTS. GALES LOOK CERTAIN OVER LK SUPERIOR AND PROBABLY WILL NEED WIND ADVISORY HEADLINES ON ADJACENT SHORELINES OF NORTHERN UPR MICHIGAN. MOST FAVORED LOCATIONS TO SEE STRONGEST WINDS WOULD BE COPPER HARBOR AND MUNISING/GRAND MARAIS/FAR NORTHERN LUCE COUNTY. WINDS DIMINISH BY MIDNIGHT THURSDAY NIGHT. COOLEST AIR SETTLES ACROSS LK SUPERIOR ON THURSDAY NIGHT WITH H85 TEMPS DOWN TO -6C OR -7C. SOUNDINGS AT END OF FETCH OVER EASTERN LK SUPERIOR INDICATE SHALLOW MOIST LAYER AROUND H85 AND DRY SUB CLOUD LAYER. KEPT LOW CHANCES IN FOR LAKE EFFECT WITH SUFFICIENT OVERWATER INSTABILITY...BUT DRY AIR BLO CLOUD BASE AND FLOW BECOMING MORE ANTICYLONIC SHOULD ALLOW FOR DIMINISHING TREND TO LAKE EFFECT INTO FRIDAY. EXPECT SKIES TO STAY MOSTLY CLOUDY WITH INCREASING WARM AIR ADVECTION OCCURRING ATOP SHALLOW COLD LAYER. MID CLOUDS INCREASE IN THE AFTN AHEAD OF NEXT CHANCE OF RAIN WHICH ARRIVES OVERNIGHT FRIDAY NIGHT. GFS IS NOW JOINED BY ECMWF IN SHOWING SWATH OF RAIN SPREADING OVER UPPER GREAT LAKES LATE FRIDAY NIGHT INTO AT LEAST SATURDAY MORNING AHEAD OF SHORTWAVE TROUGH CROSSING THE NORTHERN PLAINS. STRONGEST LOW-LEVEL MOISTURE ADVECTION REMAINS MORE OVER CNTRL AND LOWER GREAT LAKES...SO LIKELY WILL NOT SEE TOO HIGH AMOUNTS OVER UPR MICHIGAN /AROUND 0.10 INCH BUT LESS THAN 0.25 INCH/. HALLOWEEN 2014 HAD SNOW OVER PARTS OF UPR MICHIGAN SO AT LEAST WILL NOT BE LOOKING AT ANYTHING THAT COLD. TEMPS ON SATURDAY TOP OUT IN THE UPR 40S TO NEAR 50 DEGREES. WARMING TREND STILL EXPECTED INTO FIRST PART OF NEXT WEEK WITH ONLY SMALL CHANCES OF RAIN AS IT STANDS NOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 208 PM EDT TUE OCT 27 2015 VFR CONDITIONS AT TAF SITES SHOULD CONTINUE UNDER ABUNDANT MID AND HIGH CLOUDS UNTIL ARRIVAL OF -RA FROM THE SW OVERNIGHT AHEAD OF SYSTEM LIFTING UP FROM THE CENTRAL PLAINS. CONDITIONS WILL THEN DROP TO MVFR WITH ONSET OF STEADIER RAIN LATE TONIGHT AND TO LIFR BY WEDNESDAY MORNING AS HIGHER DEWPOINT AIR WITH SYSTEM LEADS TO FORMATION OF LOW STRATUS AND FOG ACROSS THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EDT TUE OCT 27 2015 WINDS WILL BEGIN TO INCREASE TODAY INTO TONIGHT AHEAD OF A STRENGTHING LOW LIFTING TOWARD THE WRN LAKES. THE LOW WILL RAPIDLY DEEPEN AS IT MOVES ACROSS THE UPPER GREAT LAKES WED AFTN/NIGHT ON ITS WAY TO JAMES BAY THU. WINDS ACROSS MUCH OF LAKE SUPERIOR WILL BE INTO THE 15-25KT RANGE BY LATE THIS AFTERNOON...INCREASING FURTHER TO 20-30KT TONIGHT. THE STRONGEST WINDS TONIGHT WILL BE FAVORED FOR CNTRL/ERN LAKE SUPERIOR...TYPICAL FOR SE FLOW. WINDS WILL TEMPORARILY DIMINISH IN THE VNCTY OF THE LOW/FRONT AS THEY MOVE ACROSS LAKE SUPERIOR WED. NW GALES WILL THEN DEVELOP BEHIND THE LOW LATE WED THRU THU WITH THE STRONGEST WINDS TO AROUND 40KT OVER THE E HALF OF THE LAKE. WINDS WILL DIMINISH TO UNDER 20KT W TO E THU NIGHT/FRI. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR LSZ267. GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR LSZ265-266. GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LSZ263-264. LAKE MICHIGAN... GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING FOR LMZ221-248-250. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...VOSS MARINE...NONE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
736 AM EDT TUE OCT 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 518 AM EDT TUE OCT 27 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A COMPLEX MID/UPPER LEVEL TROUGH DEVELOPING FROM SASK/ALBERTA INTO THE NRN ROCKIES AND WRN PLAINS WITH SEVERAL EMBEDDED SHORTWAVES. DOWNSTREAM...A RIDGE WAS BUILDING FROM THE UPPER MS VALLEY TO THE WRN GREAT LAKES. A THE SFC...SE FLOW PREVAILED THROUGH THE REGION BTWN HIGH PRES OVER NRN ONTARIO AND QUEBEC AND A TROUGH OVER THE WRN PLAINS. A BAND OF LIGHT SHOWERS OR SPRINKLES ASSOCIAED WITH WAA AND 295K ISENTROPIC LIFT NORTH OF A SFC FRONT THROUGH SRN MN. OTHERWISE...IR LOOP SHOWED MID CLOUDS SPREADING ACROSS UPPER MI WHERE AREAS OF LOW CLOUDS AND PATCHY FOG HAD ALSO DEVELOPED. TODAY...RADAR TRENDS AND SHORT RANGE MODELS SUGGEST THAT THE AREA OF LIGHT PCPN FROM N CNTRL MN INTO NW WI WILL CONTINUE TO LIFT TO THE NNE WITH ONLY A FEW SPRINKLES POSSIBLE OVER THE FAR WEST BEFORE 15Z. OTHERWISE...DRIER AIR FROM 925-850 MB MOVING IN FROM THE SOUTH COMBINED WITH LIMITED DAYTIME HEATING/MIXING SHOULD HELP SCOUR OUR THE LOWER CLOUDS THIS MORNING. HOWEVER...MID LEVEL CLOUDS WILL CONTINUE TO THICKEN. NEVERTHELESS...WAA WILL HELP PUSH HIGH TEMPS INTO THE LOWER TO MID 50S. TONIGHT...THE MODELS WERE IN GOOD AGREEMENT WITH THE CNTRL PLAINS SHORTWAVE LIFTING TOWARD IA AS A STRONGER SHRTWV OVER CNTRL SASK DROP INTO SRN MANITOBA. A DEEPENING SFC LOW WILL ALSO LIFT TO SRN WI. INCREASING SRLY 80-700 MB FLOW TO 40-50 KNOTS WILL DRAW ABUNDANT MOISTURE TOWARD UPPER MI (PWAT TO AROUND 1.0 INCH) WITH RAIN SPREADING ACROSS THE CWA LATE...MAINLY BTWN 09Z-12Z. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 512 AM EDT TUE OCT 27 2015 DEEPENING LONGWAVE TROUGH OVER THE CENTRAL CONUS ON WEDNESDAY RESULTS FROM PHASING OF MANY INDIVIDUAL SHORTWAVES STRETCHING FROM BRITISH COLUMBIA THROUGH THE INTERMOUNTAIN WEST. AS TROUGH DEEPENS SFC LOW 995-1000MB DEVELOPS OVER IA/IL/SOUTHERN WI BY 12Z ON WED. MOIST ADVECTION OF PWATS OVER 1 INCH AHEAD OF H85 TROUGH AND SFC LOW ALONG WITH H85-H5 Q-VECTOR CONVERGENCE FM THE DEEPENING TROUGH SHOULD SPREAD THE RAIN CURRENTLY OVER LOWER MISSISSIPPI RIVER VALLEY ACROSS THE UPPER GREAT LAKES BY DAYBREAK ON WEDNESDAY. ISENTROPIC ASCENT 290-300K/H9-H65 ALONG WITH THE LARGER SCALE FORCING WITH SOME ADDITIONAL ASSIST TO RIGHT ENTRANCE REGION OF UPPER JET OVER ONTARIO WILL RESULT IN MODERATE RAIN OVER UPR MICHIGAN ON WEDNESDAY. AS THE ISENTROPIC ASCENT FADES IN THE MID-LATE AFTN AND Q-VECTOR DIVERGENCE SPREADS NORTH OVER CWA IN WAKE OF INITIAL SOUTHERN STREAM SHORTWAVE EXPECT RAIN TO START TO DIMINISH. MID CONUS TROUGH CLOSES OFF SHARPLY INTO THURSDAY AS INITIAL CENTRAL CONUS TROUGH MOVING EAST PHASES WITH STRONG NORTHERN STREAM TROUGH DIGGING SSE FM SASKATCHEWAN AND MANITOBA ON WEDNESDAY MORNING TO THE WESTERN GREAT LAKES WEDNESDAY NIGHT. SFC LOW LIFTING FM THE MIDDLE MISSISSIPPI RIVER VALLEY DEEPENS TO NEAR 983-985MB AS IT REACHES SOUTH CENTRAL LK SUPERIOR WEDNESDAY EVENING THEN STAYS SIMILAR STRENGTH AS IT MOVES TO FAR EAST LK SUPERIOR OR JUST EAST OF LK SUPERIOR BY 12Z THURSDAY. TREND IS SLOWER IN MAJORITY OF GUIDANCE IN LIFTING THE LOW NORTH OF THE REGION. MAIN RESULT IS MORE WIDESPREAD PRECIP LINGERING OVER MUCH OF UPR MICHIGAN WEDNESDAY NIGHT INTO THURSDAY WITH TROWAL WORKING ACROSS WEST TO EAST AS SEEN IN THETA-E FIELDS WITH HEIGHT /ESPECIALLY H7-H6/ AND H7-H5 Q-VECTOR CONVERGENCE. ALSO SEE THE SLOWER TREND SHOW UP WITH WARMER AIR IN THE SFC-H85 LAYER ORIENTED EAST TO WEST ACROSS UPR MICHIGAN AND LK SUPERIOR. BIGGEST IMPACT IS ON SNOW POTENTIAL OVER WESTERN CWA. H85 TEMPS LAST NIGHT WERE AROUND -2C AT THE WARMEST AND -5C AT THE COOLEST BUT LATEST RUNS HAVE TRENDED WARMER. GFS/NAM SOUNDINGS AT IWD INDICATE EVEN WITH H85 TEMPS AROUND -2C OR -3C/GOOD ENOUGH FOR LAKE ENHANCEMENT WITH WATER TEMPS AROUND 8C AND PLENTY OF LARGE SCALE LIFT/MOISTURE/...WET BULB ZERO HEIGHTS REMAIN AT OR ABOVE 1000 FT AGL WHICH SUGGEST A MIX OF RAIN AND SNOW...BUT NOT MUCH SNOW ACCUMULATION. WILL BE TIGHT GRADIENT BTWN WHERE SNOW IS MAIN PYPE AND WHERE THERE WILL BE MIX OR JUST RAIN. RIGHT NOW BELIEVE THAT LINE WILL STAY MAINLY WEST AND SOUTH OF WESTERN CWA. TRENDED SNOW BACK OVER WESTERN INTERIOR TO LESS THAN 0.5 INCH. COOL AND BREEZY CONDITIONS EXPECTED ON THURSDAY ALL CWA. STRONGEST WINDS WILL BE ALONG LK SUPERIOR. SOLID 40-45 MPH IN THE MIXED LAYER THOUGH SLOWER TREND WITH SFC LOW AND LACK OF STRONG COLD AIR ADVECTION WILL COMPLICATE HOW QUICKLY THE STRONG WINDS MIX TO SFC. GOOD PORTION OF THESE WINDS WILL MAKE IT TO SFC AS GUSTS. GALES LOOK CERTAIN OVER LK SUPERIOR AND PROBABLY WILL NEED WIND ADVISORY HEADLINES ON ADJACENT SHORELINES OF NORTHERN UPR MICHIGAN. MOST FAVORED LOCATIONS TO SEE STRONGEST WINDS WOULD BE COPPER HARBOR AND MUNISING/GRAND MARAIS/FAR NORTHERN LUCE COUNTY. WINDS DIMINISH BY MIDNIGHT THURSDAY NIGHT. COOLEST AIR SETTLES ACROSS LK SUPERIOR ON THURSDAY NIGHT WITH H85 TEMPS DOWN TO -6C OR -7C. SOUNDINGS AT END OF FETCH OVER EASTERN LK SUPERIOR INDICATE SHALLOW MOIST LAYER AROUND H85 AND DRY SUB CLOUD LAYER. KEPT LOW CHANCES IN FOR LAKE EFFECT WITH SUFFICIENT OVERWATER INSTABILITY...BUT DRY AIR BLO CLOUD BASE AND FLOW BECOMING MORE ANTICYLONIC SHOULD ALLOW FOR DIMINISHING TREND TO LAKE EFFECT INTO FRIDAY. EXPECT SKIES TO STAY MOSTLY CLOUDY WITH INCREASING WARM AIR ADVECTION OCCURRING ATOP SHALLOW COLD LAYER. MID CLOUDS INCREASE IN THE AFTN AHEAD OF NEXT CHANCE OF RAIN WHICH ARRIVES OVERNIGHT FRIDAY NIGHT. GFS IS NOW JOINED BY ECMWF IN SHOWING SWATH OF RAIN SPREADING OVER UPPER GREAT LAKES LATE FRIDAY NIGHT INTO AT LEAST SATURDAY MORNING AHEAD OF SHORTWAVE TROUGH CROSSING THE NORTHERN PLAINS. STRONGEST LOW-LEVEL MOISTURE ADVECTION REMAINS MORE OVER CNTRL AND LOWER GREAT LAKES...SO LIKELY WILL NOT SEE TOO HIGH AMOUNTS OVER UPR MICHIGAN /AROUND 0.10 INCH BUT LESS THAN 0.25 INCH/. HALLOWEEN 2014 HAD SNOW OVER PARTS OF UPR MICHIGAN SO AT LEAST WILL NOT BE LOOKING AT ANYTHING THAT COLD. TEMPS ON SATURDAY TOP OUT IN THE UPR 40S TO NEAR 50 DEGREES. WARMING TREND STILL EXPECTED INTO FIRST PART OF NEXT WEEK WITH ONLY SMALL CHANCES OF RAIN AS IT STANDS NOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 734 AM EDT TUE OCT 27 2015 INCREASING SE FLOW WILL GRADUALY DRAW SOMEHWAT DRIER AIR INTO CNTRL UPPER MI. WITH THE ONSET OF LIMITED DAYTIME HEATING/MIXING CONDITIONS SHOULD IMPROVE TO MVFR BY LATE MORNING AT SAW AND TO VFR THIS AFTERNOON. ALTHOUGH ABUNDANT MID AND HIGH CLOUDS WILL PREVAIL OVER THE AREA...VFR CONDITIONS WILL CONTINUE AT IWD AND CMX. MORE CLOUDS AND SOME -RA WL ARRIVE FROM THE SW OVERNIGHT...BUT VFR CONDITIONS SHOULD PREVAIL THRU 06Z. CIGS SHOULD THEN DROP TO MVFR AT IWD AND CMX AND TO IFR AND SAW WHERE UPSLOPE FLOW DOMINATES. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EDT TUE OCT 27 2015 WINDS WILL BEGIN TO INCREASE TODAY INTO TONIGHT AHEAD OF A STRENGTHING LOW LIFTING TOWARD THE WRN LAKES. THE LOW WILL RAPIDLY DEEPEN AS IT MOVES ACROSS THE UPPER GREAT LAKES WED AFTN/NIGHT ON ITS WAY TO JAMES BAY THU. WINDS ACROSS MUCH OF LAKE SUPERIOR WILL BE INTO THE 15-25KT RANGE BY LATE THIS AFTERNOON...INCREASING FURTHER TO 20-30KT TONIGHT. THE STRONGEST WINDS TONIGHT WILL BE FAVORED FOR CNTRL/ERN LAKE SUPERIOR...TYPICAL FOR SE FLOW. WINDS WILL TEMPORARILY DIMINISH IN THE VNCTY OF THE LOW/FRONT AS THEY MOVE ACROSS LAKE SUPERIOR WED. NW GALES WILL THEN DEVELOP BEHIND THE LOW LATE WED THRU THU WITH THE STRONGEST WINDS TO AROUND 40KT OVER THE E HALF OF THE LAKE. WINDS WILL DIMINISH TO UNDER 20KT W TO E THU NIGHT/FRI. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR LSZ267. GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR LSZ265-266. GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LSZ263-264. LAKE MICHIGAN... GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING FOR LMZ221-248-250. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...JLB MARINE...- NONE -
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
526 AM EDT TUE OCT 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 518 AM EDT TUE OCT 27 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A COMPLEX MID/UPPER LEVEL TROUGH DEVELOPING FROM SASK/ALBERTA INTO THE NRN ROCKIES AND WRN PLAINS WITH SEVERAL EMBEDDED SHORTWAVES. DOWNSTREAM...A RIDGE WAS BUILDING FROM THE UPPER MS VALLEY TO THE WRN GREAT LAKES. A THE SFC...SE FLOW PREVAILED THROUGH THE REGION BTWN HIGH PRES OVER NRN ONTARIO AND QUEBEC AND A TROUGH OVER THE WRN PLAINS. A BAND OF LIGHT SHOWERS OR SPRINKLES ASSOCIAED WITH WAA AND 295K ISENTROPIC LIFT NORTH OF A SFC FRONT THROUGH SRN MN. OTHERWISE...IR LOOP SHOWED MID CLOUDS SPREADING ACROSS UPPER MI WHERE AREAS OF LOW CLOUDS AND PATCHY FOG HAD ALSO DEVELOPED. TODAY...RADAR TRENDS AND SHORT RANGE MODELS SUGGEST THAT THE AREA OF LIGHT PCPN FROM N CNTRL MN INTO NW WI WILL CONTINUE TO LIFT TO THE NNE WITH ONLY A FEW SPRINKLES POSSIBLE OVER THE FAR WEST BEFORE 15Z. OTHERWISE...DRIER AIR FROM 925-850 MB MOVING IN FROM THE SOUTH COMBINED WITH LIMITED DAYTIME HEATING/MIXING SHOULD HELP SCOUR OUR THE LOWER CLOUDS THIS MORNING. HOWEVER...MID LEVEL CLOUDS WILL CONTINUE TO THICKEN. NEVERTHELESS...WAA WILL HELP PUSH HIGH TEMPS INTO THE LOWER TO MID 50S. TONIGHT...THE MODELS WERE IN GOOD AGREEMENT WITH THE CNTRL PLAINS SHORTWAVE LIFTING TOWARD IA AS A STRONGER SHRTWV OVER CNTRL SASK DROP INTO SRN MANITOBA. A DEEPENING SFC LOW WILL ALSO LIFT TO SRN WI. INCREASING SRLY 80-700 MB FLOW TO 40-50 KNOTS WILL DRAW ABUNDANT MOISTURE TOWARD UPPER MI (PWAT TO AROUND 1.0 INCH) WITH RAIN SPREADING ACROSS THE CWA LATE...MAINLY BTWN 09Z-12Z. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 512 AM EDT TUE OCT 27 2015 DEEPENING LONGWAVE TROUGH OVER THE CENTRAL CONUS ON WEDNESDAY RESULTS FROM PHASING OF MANY INDIVIDUAL SHORTWAVES STRETCHING FROM BRITISH COLUMBIA THROUGH THE INTERMOUNTAIN WEST. AS TROUGH DEEPENS SFC LOW 995-1000MB DEVELOPS OVER IA/IL/SOUTHERN WI BY 12Z ON WED. MOIST ADVECTION OF PWATS OVER 1 INCH AHEAD OF H85 TROUGH AND SFC LOW ALONG WITH H85-H5 Q-VECTOR CONVERGENCE FM THE DEEPENING TROUGH SHOULD SPREAD THE RAIN CURRENTLY OVER LOWER MISSISSIPPI RIVER VALLEY ACROSS THE UPPER GREAT LAKES BY DAYBREAK ON WEDNESDAY. ISENTROPIC ASCENT 290-300K/H9-H65 ALONG WITH THE LARGER SCALE FORCING WITH SOME ADDITIONAL ASSIST TO RIGHT ENTRANCE REGION OF UPPER JET OVER ONTARIO WILL RESULT IN MODERATE RAIN OVER UPR MICHIGAN ON WEDNESDAY. AS THE ISENTROPIC ASCENT FADES IN THE MID-LATE AFTN AND Q-VECTOR DIVERGENCE SPREADS NORTH OVER CWA IN WAKE OF INITIAL SOUTHERN STREAM SHORTWAVE EXPECT RAIN TO START TO DIMINISH. MID CONUS TROUGH CLOSES OFF SHARPLY INTO THURSDAY AS INITIAL CENTRAL CONUS TROUGH MOVING EAST PHASES WITH STRONG NORTHERN STREAM TROUGH DIGGING SSE FM SASKATCHEWAN AND MANITOBA ON WEDNESDAY MORNING TO THE WESTERN GREAT LAKES WEDNESDAY NIGHT. SFC LOW LIFTING FM THE MIDDLE MISSISSIPPI RIVER VALLEY DEEPENS TO NEAR 983-985MB AS IT REACHES SOUTH CENTRAL LK SUPERIOR WEDNESDAY EVENING THEN STAYS SIMILAR STRENGTH AS IT MOVES TO FAR EAST LK SUPERIOR OR JUST EAST OF LK SUPERIOR BY 12Z THURSDAY. TREND IS SLOWER IN MAJORITY OF GUIDANCE IN LIFTING THE LOW NORTH OF THE REGION. MAIN RESULT IS MORE WIDESPREAD PRECIP LINGERING OVER MUCH OF UPR MICHIGAN WEDNESDAY NIGHT INTO THURSDAY WITH TROWAL WORKING ACROSS WEST TO EAST AS SEEN IN THETA-E FIELDS WITH HEIGHT /ESPECIALLY H7-H6/ AND H7-H5 Q-VECTOR CONVERGENCE. ALSO SEE THE SLOWER TREND SHOW UP WITH WARMER AIR IN THE SFC-H85 LAYER ORIENTED EAST TO WEST ACROSS UPR MICHIGAN AND LK SUPERIOR. BIGGEST IMPACT IS ON SNOW POTENTIAL OVER WESTERN CWA. H85 TEMPS LAST NIGHT WERE AROUND -2C AT THE WARMEST AND -5C AT THE COOLEST BUT LATEST RUNS HAVE TRENDED WARMER. GFS/NAM SOUNDINGS AT IWD INDICATE EVEN WITH H85 TEMPS AROUND -2C OR -3C/GOOD ENOUGH FOR LAKE ENHANCEMENT WITH WATER TEMPS AROUND 8C AND PLENTY OF LARGE SCALE LIFT/MOISTURE/...WET BULB ZERO HEIGHTS REMAIN AT OR ABOVE 1000 FT AGL WHICH SUGGEST A MIX OF RAIN AND SNOW...BUT NOT MUCH SNOW ACCUMULATION. WILL BE TIGHT GRADIENT BTWN WHERE SNOW IS MAIN PYPE AND WHERE THERE WILL BE MIX OR JUST RAIN. RIGHT NOW BELIEVE THAT LINE WILL STAY MAINLY WEST AND SOUTH OF WESTERN CWA. TRENDED SNOW BACK OVER WESTERN INTERIOR TO LESS THAN 0.5 INCH. COOL AND BREEZY CONDITIONS EXPECTED ON THURSDAY ALL CWA. STRONGEST WINDS WILL BE ALONG LK SUPERIOR. SOLID 40-45 MPH IN THE MIXED LAYER THOUGH SLOWER TREND WITH SFC LOW AND LACK OF STRONG COLD AIR ADVECTION WILL COMPLICATE HOW QUICKLY THE STRONG WINDS MIX TO SFC. GOOD PORTION OF THESE WINDS WILL MAKE IT TO SFC AS GUSTS. GALES LOOK CERTAIN OVER LK SUPERIOR AND PROBABLY WILL NEED WIND ADVISORY HEADLINES ON ADJACENT SHORELINES OF NORTHERN UPR MICHIGAN. MOST FAVORED LOCATIONS TO SEE STRONGEST WINDS WOULD BE COPPER HARBOR AND MUNISING/GRAND MARAIS/FAR NORTHERN LUCE COUNTY. WINDS DIMINISH BY MIDNIGHT THURSDAY NIGHT. COOLEST AIR SETTLES ACROSS LK SUPERIOR ON THURSDAY NIGHT WITH H85 TEMPS DOWN TO -6C OR -7C. SOUNDINGS AT END OF FETCH OVER EASTERN LK SUPERIOR INDICATE SHALLOW MOIST LAYER AROUND H85 AND DRY SUB CLOUD LAYER. KEPT LOW CHANCES IN FOR LAKE EFFECT WITH SUFFICIENT OVERWATER INSTABILITY...BUT DRY AIR BLO CLOUD BASE AND FLOW BECOMING MORE ANTICYLONIC SHOULD ALLOW FOR DIMINISHING TREND TO LAKE EFFECT INTO FRIDAY. EXPECT SKIES TO STAY MOSTLY CLOUDY WITH INCREASING WARM AIR ADVECTION OCCURRING ATOP SHALLOW COLD LAYER. MID CLOUDS INCREASE IN THE AFTN AHEAD OF NEXT CHANCE OF RAIN WHICH ARRIVES OVERNIGHT FRIDAY NIGHT. GFS IS NOW JOINED BY ECMWF IN SHOWING SWATH OF RAIN SPREADING OVER UPPER GREAT LAKES LATE FRIDAY NIGHT INTO AT LEAST SATURDAY MORNING AHEAD OF SHORTWAVE TROUGH CROSSING THE NORTHERN PLAINS. STRONGEST LOW-LEVEL MOISTURE ADVECTION REMAINS MORE OVER CNTRL AND LOWER GREAT LAKES...SO LIKELY WILL NOT SEE TOO HIGH AMOUNTS OVER UPR MICHIGAN /AROUND 0.10 INCH BUT LESS THAN 0.25 INCH/. HALLOWEEN 2014 HAD SNOW OVER PARTS OF UPR MICHIGAN SO AT LEAST WILL NOT BE LOOKING AT ANYTHING THAT COLD. TEMPS ON SATURDAY TOP OUT IN THE UPR 40S TO NEAR 50 DEGREES. WARMING TREND STILL EXPECTED INTO FIRST PART OF NEXT WEEK WITH ONLY SMALL CHANCES OF RAIN AS IT STANDS NOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 416 AM EDT TUE OCT 27 2015 WITH A LIGHT UPSLOPE SSE FLOW DVLPG OFF LK MI AND ADVECTING RA MOISTENED AIR INTO SAW IN THE PRESENCE OF NOCTURNAL COOLING... EXPECT CONDITIONS THERE TO DETERIORATE TO IFR EARLY THIS MRNG. THIS FLOW WL TAP SOME DRIER AIR NEAR GRB LATER...SO CONDITIONS ARE LIKELY TO IMPROVE TOWARD SUNRISE. AS THE SSE WIND SLOWLY INCREASES...INCRSG DOWNSLOPE WRMG AT IWD SHOULD BREAK UP THE LO CLD CIG PRESENT THERE AND BRING A RETURN OF VFR WX. ALTHOUGH CMX IS DOMINATED BY LLVL DRY AIR ATTM WITH A LGT NE WIND...SOME LO CLDS/FOG MAY IMPACT THAT SITE FOR A TIME AS THE FLOW SHIFTS MORE TO THE ESE. AS THE S WIND AHEAD OF DVLPG LO PRES TO THE W TAPS THE DRIER LLVL AIR TODAY WITH DAYTIME HEATING...ANY LINGERNIG LO CLDS WL GIVE WAY TO VFR CONDITIONS AT ALL 3 TAF SITES DESPITE PLENTY OF HIER CLDS. MORE CLDS AND SOME -RA WL ARRIVE FM THE SW TNGT...BUT VFR CONDITIONS SHOULD PREVAIL THRU 06Z. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EDT TUE OCT 27 2015 WINDS WILL BEGIN TO INCREASE TODAY INTO TONIGHT AHEAD OF A STRENGTHING LOW LIFTING TOWARD THE WRN LAKES. THE LOW WILL RAPIDLY DEEPEN AS IT MOVES ACROSS THE UPPER GREAT LAKES WED AFTN/NIGHT ON ITS WAY TO JAMES BAY THU. WINDS ACROSS MUCH OF LAKE SUPERIOR WILL BE INTO THE 15-25KT RANGE BY LATE THIS AFTERNOON...INCREASING FURTHER TO 20-30KT TONIGHT. THE STRONGEST WINDS TONIGHT WILL BE FAVORED FOR CNTRL/ERN LAKE SUPERIOR...TYPICAL FOR SE FLOW. WINDS WILL TEMPORARILY DIMINISH IN THE VNCTY OF THE LOW/FRONT AS THEY MOVE ACROSS LAKE SUPERIOR WED. NW GALES WILL THEN DEVELOP BEHIND THE LOW LATE WED THRU THU WITH THE STRONGEST WINDS TO AROUND 40KT OVER THE E HALF OF THE LAKE. WINDS WILL DIMINISH TO UNDER 20KT W TO E THU NIGHT/FRI. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR LSZ267. GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR LSZ265-266. GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LSZ263-264. LAKE MICHIGAN... GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING FOR LMZ221-248-250. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...KC MARINE...- NONE -
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
519 AM EDT TUE OCT 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 518 AM EDT TUE OCT 27 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A COMPLEX MID/UPPER LEVEL TROUGH DEVELOPING FROM SASK/ALBERTA INTO THE NRN ROCKIES AND WRN PLAINS WITH SEVERAL EMBEDDED SHORTWAVES. DOWNSTREAM...A RIDGE WAS BUILDING FROM THE UPPER MS VALLEY TO THE WRN GREAT LAKES. A THE SFC...SE FLOW PREVAILED THROUGH THE REGION BTWN HIGH PRES OVER NRN ONTARIO AND QUEBEC AND A TROUGH OVER THE WRN PLAINS. A BAND OF LIGHT SHOWERS OR SPRINKLES ASSOCIAED WITH WAA AND 295K ISENTROPIC LIFT NORTH OF A SFC FRONT THROUGH SRN MN. OTHERWISE...IR LOOP SHOWED MID CLOUDS SPREADING ACROSS UPPER MI WHERE AREAS OF LOW CLOUDS AND PATCHY FOG HAD ALSO DEVELOPED. TODAY...RADAR TRENDS AND SHORT RANGE MODELS SUGGEST THAT THE AREA OF LIGHT PCPN FROM N CNTRL MN INTO NW WI WILL CONTINUE TO LIFT TO THE NNE WITH ONLY A FEW SPRINKLES POSSIBLE OVER THE FAR WEST BEFORE 15Z. OTHERWISE...DRIER AIR FROM 925-850 MB MOVING IN FROM THE SOUTH COMBINED WITH LIMITED DAYTIME HEATING/MIXING SHOULD HELP SCOUR OUR THE LOWER CLOUDS THIS MORNING. HOWEVER...MID LEVEL CLOUDS WILL CONTINUE TO THICKEN. NEVERTHELESS...WAA WILL HELP PUSH HIGH TEMPS INTO THE LOWER TO MID 50S. TONIGHT...THE MODELS WERE IN GOOD AGREEMENT WITH THE CNTRL PLAINS SHORTWAVE LIFTING TOWARD IA AS A STRONGER SHRTWV OVER CNTRL SASK DROP INTO SRN MANITOBA. A DEEPENING SFC LOW WILL ALSO LIFT TO SRN WI. INCREASING SRLY 80-700 MB FLOW TO 40-50 KNOTS WILL DRAW ABUNDANT MOISTURE TOWARD UPPER MI (PWAT TO AROUND 1.0 INCH) WITH RAIN SPREADING ACROSS THE CWA LATE...MAINLY BTWN 09Z-12Z. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 512 AM EDT TUE OCT 27 2015 DEEPENING LONGWAVE TROUGH OVER THE CENTRAL CONUS ON WEDNESDAY RESULTS FROM PHASING OF MANY INDIVIDUAL SHORTWAVES STRETCHING FROM BRITISH COLUMBIA THROUGH THE INTERMOUNTAIN WEST. AS TROUGH DEEPENS SFC LOW 995-1000MB DEVELOPS OVER IA/IL/SOUTHERN WI BY 12Z ON WED. MOIST ADVECTION OF PWATS OVER 1 INCH AHEAD OF H85 TROUGH AND SFC LOW ALONG WITH H85-H5 Q-VECTOR CONVERGENCE FM THE DEEPENING TROUGH SHOULD SPREAD THE RAIN CURRENTLY OVER LOWER MISSISSIPPI RIVER VALLEY ACROSS THE UPPER GREAT LAKES BY DAYBREAK ON WEDNESDAY. ISENTROPIC ASCENT 290-300K/H9-H65 ALONG WITH THE LARGER SCALE FORCING WITH SOME ADDITIONAL ASSIST TO RIGHT ENTRANCE REGION OF UPPER JET OVER ONTARIO WILL RESULT IN MODERATE RAIN OVER UPR MICHIGAN ON WEDNESDAY. AS THE ISENTROPIC ASCENT FADES IN THE MID-LATE AFTN AND Q-VECTOR DIVERGENCE SPREADS NORTH OVER CWA IN WAKE OF INITIAL SOUTHERN STREAM SHORTWAVE EXPECT RAIN TO START TO DIMINISH. MID CONUS TROUGH CLOSES OFF SHARPLY INTO THURSDAY AS INITIAL CENTRAL CONUS TROUGH MOVING EAST PHASES WITH STRONG NORTHERN STREAM TROUGH DIGGING SSE FM SASKATCHEWAN AND MANITOBA ON WEDNESDAY MORNING TO THE WESTERN GREAT LAKES WEDNESDAY NIGHT. SFC LOW LIFTING FM THE MIDDLE MISSISSIPPI RIVER VALLEY DEEPENS TO NEAR 983-985MB AS IT REACHES SOUTH CENTRAL LK SUPERIOR WEDNESDAY EVENING THEN STAYS SIMILAR STRENGTH AS IT MOVES TO FAR EAST LK SUPERIOR OR JUST EAST OF LK SUPERIOR BY 12Z THURSDAY. TREND IS SLOWER IN MAJORITY OF GUIDANCE IN LIFTING THE LOW NORTH OF THE REGION. MAIN RESULT IS MORE WIDESPREAD PRECIP LINGERING OVER MUCH OF UPR MICHIGAN WEDNESDAY NIGHT INTO THURSDAY WITH TROWAL WORKING ACROSS WEST TO EAST AS SEEN IN THETA-E FIELDS WITH HEIGHT /ESPECIALLY H7-H6/ AND H7-H5 Q-VECTOR CONVERGENCE. ALSO SEE THE SLOWER TREND SHOW UP WITH WARMER AIR IN THE SFC-H85 LAYER ORIENTED EAST TO WEST ACROSS UPR MICHIGAN AND LK SUPERIOR. BIGGEST IMPACT IS ON SNOW POTENTIAL OVER WESTERN CWA. H85 TEMPS LAST NIGHT WERE AROUND -2C AT THE WARMEST AND -5C AT THE COOLEST BUT LATEST RUNS HAVE TRENDED WARMER. GFS/NAM SOUNDINGS AT IWD INDICATE EVEN WITH H85 TEMPS AROUND -2C OR -3C/GOOD ENOUGH FOR LAKE ENHANCEMENT WITH WATER TEMPS AROUND 8C AND PLENTY OF LARGE SCALE LIFT/MOISTURE/...WET BULB ZERO HEIGHTS REMAIN AT OR ABOVE 1000 FT AGL WHICH SUGGEST A MIX OF RAIN AND SNOW...BUT NOT MUCH SNOW ACCUMULATION. WILL BE TIGHT GRADIENT BTWN WHERE SNOW IS MAIN PYPE AND WHERE THERE WILL BE MIX OR JUST RAIN. RIGHT NOW BELIEVE THAT LINE WILL STAY MAINLY WEST AND SOUTH OF WESTERN CWA. TRENDED SNOW BACK OVER WESTERN INTERIOR TO LESS THAN 0.5 INCH. COOL AND BREEZY CONDITIONS EXPECTED ON THURSDAY ALL CWA. STRONGEST WINDS WILL BE ALONG LK SUPERIOR. SOLID 40-45 MPH IN THE MIXED LAYER THOUGH SLOWER TREND WITH SFC LOW AND LACK OF STRONG COLD AIR ADVECTION WILL COMPLICATE HOW QUICKLY THE STRONG WINDS MIX TO SFC. GOOD PORTION OF THESE WINDS WILL MAKE IT TO SFC AS GUSTS. GALES LOOK CERTAIN OVER LK SUPERIOR AND PROBABLY WILL NEED WIND ADVISORY HEADLINES ON ADJACENT SHORELINES OF NORTHERN UPR MICHIGAN. MOST FAVORED LOCATIONS TO SEE STRONGEST WINDS WOULD BE COPPER HARBOR AND MUNISING/GRAND MARAIS/FAR NORTHERN LUCE COUNTY. WINDS DIMINISH BY MIDNIGHT THURSDAY NIGHT. COOLEST AIR SETTLES ACROSS LK SUPERIOR ON THURSDAY NIGHT WITH H85 TEMPS DOWN TO -6C OR -7C. SOUNDINGS AT END OF FETCH OVER EASTERN LK SUPERIOR INDICATE SHALLOW MOIST LAYER AROUND H85 AND DRY SUB CLOUD LAYER. KEPT LOW CHANCES IN FOR LAKE EFFECT WITH SUFFICIENT OVERWATER INSTABILITY...BUT DRY AIR BLO CLOUD BASE AND FLOW BECOMING MORE ANTICYLONIC SHOULD ALLOW FOR DIMINISHING TREND TO LAKE EFFECT INTO FRIDAY. EXPECT SKIES TO STAY MOSTLY CLOUDY WITH INCREASING WARM AIR ADVECTION OCCURRING ATOP SHALLOW COLD LAYER. MID CLOUDS INCREASE IN THE AFTN AHEAD OF NEXT CHANCE OF RAIN WHICH ARRIVES OVERNIGHT FRIDAY NIGHT. GFS IS NOW JOINED BY ECMWF IN SHOWING SWATH OF RAIN SPREADING OVER UPPER GREAT LAKES LATE FRIDAY NIGHT INTO AT LEAST SATURDAY MORNING AHEAD OF SHORTWAVE TROUGH CROSSING THE NORTHERN PLAINS. STRONGEST LOW-LEVEL MOISTURE ADVECTION REMAINS MORE OVER CNTRL AND LOWER GREAT LAKES...SO LIKELY WILL NOT SEE TOO HIGH AMOUNTS OVER UPR MICHIGAN /AROUND 0.10 INCH BUT LESS THAN 0.25 INCH/. HALLOWEEN 2014 HAD SNOW OVER PARTS OF UPR MICHIGAN SO AT LEAST WILL NOT BE LOOKING AT ANYTHING THAT COLD. TEMPS ON SATURDAY TOP OUT IN THE UPR 40S TO NEAR 50 DEGREES. WARMING TREND STILL EXPECTED INTO FIRST PART OF NEXT WEEK WITH ONLY SMALL CHANCES OF RAIN AS IT STANDS NOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 416 AM EDT TUE OCT 27 2015 WITH A LIGHT UPSLOPE SSE FLOW DVLPG OFF LK MI AND ADVECTING RA MOISTENED AIR INTO SAW IN THE PRESENCE OF NOCTURNAL COOLING... EXPECT CONDITIONS THERE TO DETERIORATE TO IFR EARLY THIS MRNG. THIS FLOW WL TAP SOME DRIER AIR NEAR GRB LATER...SO CONDITIONS ARE LIKELY TO IMPROVE TOWARD SUNRISE. AS THE SSE WIND SLOWLY INCREASES...INCRSG DOWNSLOPE WRMG AT IWD SHOULD BREAK UP THE LO CLD CIG PRESENT THERE AND BRING A RETURN OF VFR WX. ALTHOUGH CMX IS DOMINATED BY LLVL DRY AIR ATTM WITH A LGT NE WIND...SOME LO CLDS/FOG MAY IMPACT THAT SITE FOR A TIME AS THE FLOW SHIFTS MORE TO THE ESE. AS THE S WIND AHEAD OF DVLPG LO PRES TO THE W TAPS THE DRIER LLVL AIR TODAY WITH DAYTIME HEATING...ANY LINGERNIG LO CLDS WL GIVE WAY TO VFR CONDITIONS AT ALL 3 TAF SITES DESPITE PLENTY OF HIER CLDS. MORE CLDS AND SOME -RA WL ARRIVE FM THE SW TNGT...BUT VFR CONDITIONS SHOULD PREVAIL THRU 06Z. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 419 PM EDT MON OCT 26 2015 LIGHT WINDS MOSTLY UNDER 15KT WILL START THE FCST PERIOD TONIGHT ACROSS MOST OF LAKE SUPERIOR. WINDS OVER WRN LAKE SUPERIOR WILL GUST UP TOWARD 20KT. WINDS WILL BEGIN TO RAMP UP ON TUE AHEAD OF A COLD FRONT SWEEPING ACROSS THE PLAINS. AS THE COLD FRONT REACHES THE UPPER LAKES WED...LOW PRES WILL ORGANIZE ALONG THE FRONT. THE LOW WILL THEN RAPIDLY DEEPEN AS IT MOVES ACROSS THE UPPER GREAT LAKES WED AFTN/NIGHT ON ITS WAY TO JAMES BAY THU. WINDS ACROSS MUCH OF LAKE SUPERIOR WILL BE INTO THE 15-25KT RANGE BY LATE TUE AFTN... INCREASING FURTHER TO 20-30KT TUE NIGHT. THE STRONGEST WINDS TUE NIGHT WILL BE FAVORED FOR CNTRL/ERN LAKE SUPERIOR...TYPICAL FOR SE FLOW. NOT OUT OF THE QUESTION THAT THERE COULD BE SOME GALE FORCE GUSTS TUE NIGHT OVER CNTRL/ERN LAKE SUPERIOR...ESPECIALLY IN THE CARIBOU ISLAND/WHITEFISH POINT AREA. WINDS WILL TEMPORARILY DIMINISH IN THE VNCTY OF THE LOW/FRONT AS THEY MOVE ACROSS LAKE SUPERIOR WED. NW GALES WILL THEN DEVELOP BEHIND THE LOW LATE WED THRU THU WITH THE STRONGEST WINDS TO AROUND 40KT OVER THE E HALF OF THE LAKE. WINDS WILL DIMINISH TO UNDER 20KT W TO E THU NIGHT/FRI. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR LSZ267. GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR LSZ265-266. GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LSZ263-264. LAKE MICHIGAN... GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING FOR LMZ221-248-250. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...KC MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
512 AM EDT TUE OCT 27 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 419 PM EDT MON OCT 26 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW THE UPPER GREAT LAKES ON THE SRN PERIPHERY OF AN ERN CANADA TROF ANCHORED BY A DEEP MID LEVEL LOW CENTERED JUST N OF HUDSON BAY. WITHIN THE TROF...110KT UPPER JET EXTENDS FROM NE MN TO NEW ENGLAND. RIGHT ENTRANCE UPPER DIVERGENCE ASSOCIATED WITH THE JET...CORRESPONDING FGEN IN THE LOWER TO MID LEVELS...AND SHORTWAVE HAVE SUPPORTED SHRA FROM NW WI E ACROSS UPPER MI TODAY...THOUGH SHRA HAVE BEEN CONFINED TO ROUGHLY THE SRN HALF OF THE U.P. OTHERWISE...IT`S BEEN A CLOUDY DAY. HOWEVER...RECENTLY MID CLOUDS HAVE CLEARED OUT OVER THE KEWEENAW WITH DAYTIME HEATING NOW LEADING TO SOME DIURNAL CU/STRATOCU DEVELOPMENT THERE. TEMPS ARE IN THE 40S ACROSS THE FCST AREA...BUT ARE NEARING 50F ON THE KEWEENAW AND HAVE RISEN INTO THE LOW/MID 50S IN MENOMINEE COUNTY. WITH FORCING THAT HAS GENERATED THE SHRA TODAY BREAKING DOWN THIS EVENING...EXPECT A DIMINISHING TREND TO THE SHRA AS MODELS INDICATE. HOWEVER...ONGOING WAA AHEAD OF TROF SWINGING ACROSS THE ROCKIES MAY WORK TO GENERATE ISOLD -SHRA/SPRINKLES ALONG THE CURRENT PCPN GENERATION ZONE THAT IS SLOWLY LIFTING NE AS SEEN ON RADAR IMAGERY LOOPS ACROSS NW WI TO AROUND KDLH. TO ACCOUNT FOR THIS POSSIBILITY...LINGERED SOME SCHC POPS W INTO PORTIONS OF WRN UPPER THRU THE EVENING. TROF MOVING ACROSS THE ROCKIES TONIGHT SHIFTS OUT OVER THE PLAINS TUE. AHEAD OF THE TROF...MODELS SHOW BETTER FOCUS OF WAA SHIFTING TO THE NW OF UPPER MI. END RESULT WILL BE A DRY DAY...BUT WITH CONSIDERABLE MID AND HIGH CLOUDS OVERSPREADING THE AREA. DESPITE CLOUD COVER...TEMPS WILL TOP OUT A LITTLE ABOVE NORMAL IN THE LOW/MID 50S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 512 AM EDT TUE OCT 27 2015 DEEPENING LONGWAVE TROUGH OVER THE CENTRAL CONUS ON WEDNESDAY RESULTS FROM PHASING OF MANY INDIVIDUAL SHORTWAVES STRETCHING FROM BRITISH COLUMBIA THROUGH THE INTERMOUNTAIN WEST. AS TROUGH DEEPENS SFC LOW 995-1000MB DEVELOPS OVER IA/IL/SOUTHERN WI BY 12Z ON WED. MOIST ADVECTION OF PWATS OVER 1 INCH AHEAD OF H85 TROUGH AND SFC LOW ALONG WITH H85-H5 Q-VECTOR CONVERGENCE FM THE DEEPENING TROUGH SHOULD SPREAD THE RAIN CURRENTLY OVER LOWER MISSISSIPPI RIVER VALLEY ACROSS THE UPPER GREAT LAKES BY DAYBREAK ON WEDNESDAY. ISENTROPIC ASCENT 290-300K/H9-H65 ALONG WITH THE LARGER SCALE FORCING WITH SOME ADDITIONAL ASSIST TO RIGHT ENTRANCE REGION OF UPPER JET OVER ONTARIO WILL RESULT IN MODERATE RAIN OVER UPR MICHIGAN ON WEDNESDAY. AS THE ISENTROPIC ASCENT FADES IN THE MID-LATE AFTN AND Q-VECTOR DIVERGENCE SPREADS NORTH OVER CWA IN WAKE OF INITIAL SOUTHERN STREAM SHORTWAVE EXPECT RAIN TO START TO DIMINISH. MID CONUS TROUGH CLOSES OFF SHARPLY INTO THURSDAY AS INITIAL CENTRAL CONUS TROUGH MOVING EAST PHASES WITH STRONG NORTHERN STREAM TROUGH DIGGING SSE FM SASKATCHEWAN AND MANITOBA ON WEDNESDAY MORNING TO THE WESTERN GREAT LAKES WEDNESDAY NIGHT. SFC LOW LIFTING FM THE MIDDLE MISSISSIPPI RIVER VALLEY DEEPENS TO NEAR 983-985MB AS IT REACHES SOUTH CENTRAL LK SUPERIOR WEDNESDAY EVENING THEN STAYS SIMILAR STRENGTH AS IT MOVES TO FAR EAST LK SUPERIOR OR JUST EAST OF LK SUPERIOR BY 12Z THURSDAY. TREND IS SLOWER IN MAJORITY OF GUIDANCE IN LIFTING THE LOW NORTH OF THE REGION. MAIN RESULT IS MORE WIDESPREAD PRECIP LINGERING OVER MUCH OF UPR MICHIGAN WEDNESDAY NIGHT INTO THURSDAY WITH TROWAL WORKING ACROSS WEST TO EAST AS SEEN IN THETA-E FIELDS WITH HEIGHT /ESPECIALLY H7-H6/ AND H7-H5 Q-VECTOR CONVERGENCE. ALSO SEE THE SLOWER TREND SHOW UP WITH WARMER AIR IN THE SFC-H85 LAYER ORIENTED EAST TO WEST ACROSS UPR MICHIGAN AND LK SUPERIOR. BIGGEST IMPACT IS ON SNOW POTENTIAL OVER WESTERN CWA. H85 TEMPS LAST NIGHT WERE AROUND -2C AT THE WARMEST AND -5C AT THE COOLEST BUT LATEST RUNS HAVE TRENDED WARMER. GFS/NAM SOUNDINGS AT IWD INDICATE EVEN WITH H85 TEMPS AROUND -2C OR -3C/GOOD ENOUGH FOR LAKE ENHANCEMENT WITH WATER TEMPS AROUND 8C AND PLENTY OF LARGE SCALE LIFT/MOISTURE/...WET BULB ZERO HEIGHTS REMAIN AT OR ABOVE 1000 FT AGL WHICH SUGGEST A MIX OF RAIN AND SNOW...BUT NOT MUCH SNOW ACCUMULATION. WILL BE TIGHT GRADIENT BTWN WHERE SNOW IS MAIN PYPE AND WHERE THERE WILL BE MIX OR JUST RAIN. RIGHT NOW BELIEVE THAT LINE WILL STAY MAINLY WEST AND SOUTH OF WESTERN CWA. TRENDED SNOW BACK OVER WESTERN INTERIOR TO LESS THAN 0.5 INCH. COOL AND BREEZY CONDITIONS EXPECTED ON THURSDAY ALL CWA. STRONGEST WINDS WILL BE ALONG LK SUPERIOR. SOLID 40-45 MPH IN THE MIXED LAYER THOUGH SLOWER TREND WITH SFC LOW AND LACK OF STRONG COLD AIR ADVECTION WILL COMPLICATE HOW QUICKLY THE STRONG WINDS MIX TO SFC. GOOD PORTION OF THESE WINDS WILL MAKE IT TO SFC AS GUSTS. GALES LOOK CERTAIN OVER LK SUPERIOR AND PROBABLY WILL NEED WIND ADVISORY HEADLINES ON ADJACENT SHORELINES OF NORTHERN UPR MICHIGAN. MOST FAVORED LOCATIONS TO SEE STRONGEST WINDS WOULD BE COPPER HARBOR AND MUNISING/GRAND MARAIS/FAR NORTHERN LUCE COUNTY. WINDS DIMINISH BY MIDNIGHT THURSDAY NIGHT. COOLEST AIR SETTLES ACROSS LK SUPERIOR ON THURSDAY NIGHT WITH H85 TEMPS DOWN TO -6C OR -7C. SOUNDINGS AT END OF FETCH OVER EASTERN LK SUPERIOR INDICATE SHALLOW MOIST LAYER AROUND H85 AND DRY SUB CLOUD LAYER. KEPT LOW CHANCES IN FOR LAKE EFFECT WITH SUFFICIENT OVERWATER INSTABILITY...BUT DRY AIR BLO CLOUD BASE AND FLOW BECOMING MORE ANTICYLONIC SHOULD ALLOW FOR DIMINISHING TREND TO LAKE EFFECT INTO FRIDAY. EXPECT SKIES TO STAY MOSTLY CLOUDY WITH INCREASING WARM AIR ADVECTION OCCURRING ATOP SHALLOW COLD LAYER. MID CLOUDS INCREASE IN THE AFTN AHEAD OF NEXT CHANCE OF RAIN WHICH ARRIVES OVERNIGHT FRIDAY NIGHT. GFS IS NOW JOINED BY ECMWF IN SHOWING SWATH OF RAIN SPREADING OVER UPPER GREAT LAKES LATE FRIDAY NIGHT INTO AT LEAST SATURDAY MORNING AHEAD OF SHORTWAVE TROUGH CROSSING THE NORTHERN PLAINS. STRONGEST LOW-LEVEL MOISTURE ADVECTION REMAINS MORE OVER CNTRL AND LOWER GREAT LAKES...SO LIKELY WILL NOT SEE TOO HIGH AMOUNTS OVER UPR MICHIGAN /AROUND 0.10 INCH BUT LESS THAN 0.25 INCH/. HALLOWEEN 2014 HAD SNOW OVER PARTS OF UPR MICHIGAN SO AT LEAST WILL NOT BE LOOKING AT ANYTHING THAT COLD. TEMPS ON SATURDAY TOP OUT IN THE UPR 40S TO NEAR 50 DEGREES. WARMING TREND STILL EXPECTED INTO FIRST PART OF NEXT WEEK WITH ONLY SMALL CHANCES OF RAIN AS IT STANDS NOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 416 AM EDT TUE OCT 27 2015 WITH A LIGHT UPSLOPE SSE FLOW DVLPG OFF LK MI AND ADVECTING RA MOISTENED AIR INTO SAW IN THE PRESENCE OF NOCTURNAL COOLING... EXPECT CONDITIONS THERE TO DETERIORATE TO IFR EARLY THIS MRNG. THIS FLOW WL TAP SOME DRIER AIR NEAR GRB LATER...SO CONDITIONS ARE LIKELY TO IMPROVE TOWARD SUNRISE. AS THE SSE WIND SLOWLY INCREASES...INCRSG DOWNSLOPE WRMG AT IWD SHOULD BREAK UP THE LO CLD CIG PRESENT THERE AND BRING A RETURN OF VFR WX. ALTHOUGH CMX IS DOMINATED BY LLVL DRY AIR ATTM WITH A LGT NE WIND...SOME LO CLDS/FOG MAY IMPACT THAT SITE FOR A TIME AS THE FLOW SHIFTS MORE TO THE ESE. AS THE S WIND AHEAD OF DVLPG LO PRES TO THE W TAPS THE DRIER LLVL AIR TODAY WITH DAYTIME HEATING...ANY LINGERNIG LO CLDS WL GIVE WAY TO VFR CONDITIONS AT ALL 3 TAF SITES DESPITE PLENTY OF HIER CLDS. MORE CLDS AND SOME -RA WL ARRIVE FM THE SW TNGT...BUT VFR CONDITIONS SHOULD PREVAIL THRU 06Z. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 419 PM EDT MON OCT 26 2015 LIGHT WINDS MOSTLY UNDER 15KT WILL START THE FCST PERIOD TONIGHT ACROSS MOST OF LAKE SUPERIOR. WINDS OVER WRN LAKE SUPERIOR WILL GUST UP TOWARD 20KT. WINDS WILL BEGIN TO RAMP UP ON TUE AHEAD OF A COLD FRONT SWEEPING ACROSS THE PLAINS. AS THE COLD FRONT REACHES THE UPPER LAKES WED...LOW PRES WILL ORGANIZE ALONG THE FRONT. THE LOW WILL THEN RAPIDLY DEEPEN AS IT MOVES ACROSS THE UPPER GREAT LAKES WED AFTN/NIGHT ON ITS WAY TO JAMES BAY THU. WINDS ACROSS MUCH OF LAKE SUPERIOR WILL BE INTO THE 15-25KT RANGE BY LATE TUE AFTN... INCREASING FURTHER TO 20-30KT TUE NIGHT. THE STRONGEST WINDS TUE NIGHT WILL BE FAVORED FOR CNTRL/ERN LAKE SUPERIOR...TYPICAL FOR SE FLOW. NOT OUT OF THE QUESTION THAT THERE COULD BE SOME GALE FORCE GUSTS TUE NIGHT OVER CNTRL/ERN LAKE SUPERIOR...ESPECIALLY IN THE CARIBOU ISLAND/WHITEFISH POINT AREA. WINDS WILL TEMPORARILY DIMINISH IN THE VNCTY OF THE LOW/FRONT AS THEY MOVE ACROSS LAKE SUPERIOR WED. NW GALES WILL THEN DEVELOP BEHIND THE LOW LATE WED THRU THU WITH THE STRONGEST WINDS TO AROUND 40KT OVER THE E HALF OF THE LAKE. WINDS WILL DIMINISH TO UNDER 20KT W TO E THU NIGHT/FRI. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR LSZ267. GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR LSZ265-266. GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LSZ263-264. LAKE MICHIGAN... GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING FOR LMZ221-248-250. && $$ SHORT TERM...ROLFSON LONG TERM...JLA AVIATION...KC MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
417 AM EDT TUE OCT 27 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 419 PM EDT MON OCT 26 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW THE UPPER GREAT LAKES ON THE SRN PERIPHERY OF AN ERN CANADA TROF ANCHORED BY A DEEP MID LEVEL LOW CENTERED JUST N OF HUDSON BAY. WITHIN THE TROF...110KT UPPER JET EXTENDS FROM NE MN TO NEW ENGLAND. RIGHT ENTRANCE UPPER DIVERGENCE ASSOCIATED WITH THE JET...CORRESPONDING FGEN IN THE LOWER TO MID LEVELS...AND SHORTWAVE HAVE SUPPORTED SHRA FROM NW WI E ACROSS UPPER MI TODAY...THOUGH SHRA HAVE BEEN CONFINED TO ROUGHLY THE SRN HALF OF THE U.P. OTHERWISE...IT`S BEEN A CLOUDY DAY. HOWEVER...RECENTLY MID CLOUDS HAVE CLEARED OUT OVER THE KEWEENAW WITH DAYTIME HEATING NOW LEADING TO SOME DIURNAL CU/STRATOCU DEVELOPMENT THERE. TEMPS ARE IN THE 40S ACROSS THE FCST AREA...BUT ARE NEARING 50F ON THE KEWEENAW AND HAVE RISEN INTO THE LOW/MID 50S IN MENOMINEE COUNTY. WITH FORCING THAT HAS GENERATED THE SHRA TODAY BREAKING DOWN THIS EVENING...EXPECT A DIMINISHING TREND TO THE SHRA AS MODELS INDICATE. HOWEVER...ONGOING WAA AHEAD OF TROF SWINGING ACROSS THE ROCKIES MAY WORK TO GENERATE ISOLD -SHRA/SPRINKLES ALONG THE CURRENT PCPN GENERATION ZONE THAT IS SLOWLY LIFTING NE AS SEEN ON RADAR IMAGERY LOOPS ACROSS NW WI TO AROUND KDLH. TO ACCOUNT FOR THIS POSSIBILITY...LINGERED SOME SCHC POPS W INTO PORTIONS OF WRN UPPER THRU THE EVENING. TROF MOVING ACROSS THE ROCKIES TONIGHT SHIFTS OUT OVER THE PLAINS TUE. AHEAD OF THE TROF...MODELS SHOW BETTER FOCUS OF WAA SHIFTING TO THE NW OF UPPER MI. END RESULT WILL BE A DRY DAY...BUT WITH CONSIDERABLE MID AND HIGH CLOUDS OVERSPREADING THE AREA. DESPITE CLOUD COVER...TEMPS WILL TOP OUT A LITTLE ABOVE NORMAL IN THE LOW/MID 50S. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 423 PM EDT MON OCT 26 2015 MUCH OF THIS PERIOD WILL BE DOMINATED BY STEADY RAIN WEDNESDAY THEN COOLER/BREEZY CONDITIONS WITH LAKE EFFECT RAIN AND SNOW SHOWERS THURSDAY INTO FRIDAY. AT 00Z WEDNESDAY UPPER MI WILL BE IN BETWEEN A STRONG SFC HIGH PUSHING OFF THE NEW ENGLAND COAST...AND AN ELONGATED AREA OF LOW PRESSURE STRETCHING FROM THE N SASKATCHEWAN AND MANITOBA BORDER TO NE...AND THE LOWER MS VALLEY /REMNANTS OF HURRICANE PATRICA/. WILL BE STARTING OUT WITH A STRONG S-SE PUSH OF AIR ON 850MB WINDS OF 25- 40KTS OVERHEAD. THESE 850MB WINDS WILL INCREASE TO AN AVERAGE 40KTS CWA WIDE OVERNIGHT. THE CONSOLIDATING AREA OF LOW PRESSURE WILL CONVERGE AND STRETCH FROM MANITOBA TO IL/IN BY DAYBREAK WEDNESDAY...WITH STEADY RAIN THROUGH MID AFTERNOON. PRECIP TOTALS EARLY WEDNESDAY MORNING THROUGH THE REST OF THE DAY WILL LIKELY TOTAL AROUND OR OVER 0.5IN. THE SFC LOW WILL THEN DEEPEN TO NEAR 990MB EARLY WEDNESDAY AFTERNOON ACROSS UPPER MI/N LAKE MI...AND AROUND 980MB ACROSS N OR NE LAKE SUPERIOR BY 00Z THURSDAY. SO AFTER A BRIEF LULL IN THE WINDS MIDDAY WEDNESDAY AS THE LOW PRESSES...EXPECT STRONGER W-NW WINDS TO PUSH IN WEDNESDAY NIGHT. RAIN WILL BEGIN TO MIX WITH AND CHANGE OVER TO SNOW MAINLY INLAND FROM THE GREAT LAKES AS 850MB TEMPS FALL FROM AROUND 3C WEDNESDAY AFTERNOON TO 0 TO -5C BY 12Z THURSDAY. THE CONSENSUS...WITH THE COLD AIR IS TO HAVE IT PUSH MAINLY INLAND OR S OF THE CWA. THIS RESULTS IN ONLY MODERATE CONFIDENCE IN THE TIMING OR AMOUNTS OF SNOW POSSIBLE BEHIND THE LOW...AS THERE IS SOME DISCREPANCY ON THE HANDLING OF THE 500MB LOW AS IT SINKS IN BEHIND THE SFC LOW. STILL...IT WILL BE A COOL AND BREEZY DAY WITH GALES LIKELY CENTRAL AND E OVER LAKE SUPERIOR. THE GFS AND CANADIAN SOLUTIONS ARE THE FARTHEST S WITH THE LOW...ACROSS CENTRAL LAKE MI AND S WI AT 06Z THURSDAY. BY CONTRAST...THE NAM/ECMWF/SREF SOLUTIONS HAVE THE LOW OVER UPPER MI. WILL BE INTERESTING HOW THIS FALLS OVER THE NEXT COUPLE OF DAYS. WILL CONTINUE WITH A BLENDED SOLUTION FOR NOW. CONFIDENCE INCREASES AT THE TAIL END OF THE MOISTURE AS IT DEPARTS THURSDAY AFTERNOON. NW WINDS AND COOLER AIR WITH 850MB TEMPS AVERAGING -4 TO -5C WOULD RESULT IN MAINLY SNOW IF SFC TEMPS WERE JUST A COUPLE OF DEGREES COOLER. OTHERWISE...LOOK FOR SLOWLY RISING TEMPS FOR HIGHS THROUGH MONDAY. THIS WILL BE AS THE SFC RIDGE BUILDS INTO MUCH OF THE E HALF OF THE NATION FRIDAY. THIS AREA OF HIGH PRESSURE WILL EXIT TO OUR E FRIDAY NIGHT...AS WE RESIDE IN BETWEEN THE DEPARTING HIGH AND NEARING AREA OF LOW PRESSURE ACROSS W AND CENTRAL CANADA. WILL BE HARD TO COMPLETELY RULE OUT PRECIP FRIDAY NIGHT THROUGH MONDAY /WITH THE BEST CHANCE MONDAY WITH LOW PRESSURE NEARBY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 416 AM EDT TUE OCT 27 2015 WITH A LIGHT UPSLOPE SSE FLOW DVLPG OFF LK MI AND ADVECTING RA MOISTENED AIR INTO SAW IN THE PRESENCE OF NOCTURNAL COOLING... EXPECT CONDITIONS THERE TO DETERIORATE TO IFR EARLY THIS MRNG. THIS FLOW WL TAP SOME DRIER AIR NEAR GRB LATER...SO CONDITIONS ARE LIKELY TO IMPROVE TOWARD SUNRISE. AS THE SSE WIND SLOWLY INCREASES...INCRSG DOWNSLOPE WRMG AT IWD SHOULD BREAK UP THE LO CLD CIG PRESENT THERE AND BRING A RETURN OF VFR WX. ALTHOUGH CMX IS DOMINATED BY LLVL DRY AIR ATTM WITH A LGT NE WIND...SOME LO CLDS/FOG MAY IMPACT THAT SITE FOR A TIME AS THE FLOW SHIFTS MORE TO THE ESE. AS THE S WIND AHEAD OF DVLPG LO PRES TO THE W TAPS THE DRIER LLVL AIR TODAY WITH DAYTIME HEATING...ANY LINGERNIG LO CLDS WL GIVE WAY TO VFR CONDITIONS AT ALL 3 TAF SITES DESPITE PLENTY OF HIER CLDS. MORE CLDS AND SOME -RA WL ARRIVE FM THE SW TNGT...BUT VFR CONDITIONS SHOULD PREVAIL THRU 06Z. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 419 PM EDT MON OCT 26 2015 LIGHT WINDS MOSTLY UNDER 15KT WILL START THE FCST PERIOD TONIGHT ACROSS MOST OF LAKE SUPERIOR. WINDS OVER WRN LAKE SUPERIOR WILL GUST UP TOWARD 20KT. WINDS WILL BEGIN TO RAMP UP ON TUE AHEAD OF A COLD FRONT SWEEPING ACROSS THE PLAINS. AS THE COLD FRONT REACHES THE UPPER LAKES WED...LOW PRES WILL ORGANIZE ALONG THE FRONT. THE LOW WILL THEN RAPIDLY DEEPEN AS IT MOVES ACROSS THE UPPER GREAT LAKES WED AFTN/NIGHT ON ITS WAY TO JAMES BAY THU. WINDS ACROSS MUCH OF LAKE SUPERIOR WILL BE INTO THE 15-25KT RANGE BY LATE TUE AFTN... INCREASING FURTHER TO 20-30KT TUE NIGHT. THE STRONGEST WINDS TUE NIGHT WILL BE FAVORED FOR CNTRL/ERN LAKE SUPERIOR...TYPICAL FOR SE FLOW. NOT OUT OF THE QUESTION THAT THERE COULD BE SOME GALE FORCE GUSTS TUE NIGHT OVER CNTRL/ERN LAKE SUPERIOR...ESPECIALLY IN THE CARIBOU ISLAND/WHITEFISH POINT AREA. WINDS WILL TEMPORARILY DIMINISH IN THE VNCTY OF THE LOW/FRONT AS THEY MOVE ACROSS LAKE SUPERIOR WED. NW GALES WILL THEN DEVELOP BEHIND THE LOW LATE WED THRU THU WITH THE STRONGEST WINDS TO AROUND 40KT OVER THE E HALF OF THE LAKE. WINDS WILL DIMINISH TO UNDER 20KT W TO E THU NIGHT/FRI. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR LSZ267. GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR LSZ265-266. GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING FOR LSZ263-264. LAKE MICHIGAN... GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING FOR LMZ221-248-250. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...KC MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
656 PM CDT WED OCT 28 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 315 PM CDT WED OCT 28 2015 SFC ANALYSIS DEPICTS A TIGHTLY WOUND UP LOW OVER THE CENTRAL GREAT LAKES REGION WITH A COLD FRONT HAVING PASSED JUST E OF THE WFO MPX CWFA AND A TRAILING SECONDARY TROF AXIS ROTATING THRU NRN MN. THE CURRENT SWATH OF RAIN/SNOW OVER MAINLY NRN AND ERN PORTIONS OF THE CWFA WILL STEADILY SHIFT EWD THRU THE REST OF THIS EVENING...BRINGING A TEMPORARY REPRIEVE FROM THE PRECIPITATION AS MORE IS EXPECTED LATER THIS EVENING AND TONIGHT IN ASSOCIATION WITH A SECONDARY TRAILING TROF. THIS TROF WILL SLOWLY SWING THRU CENTRAL-ERN MN INTO WRN WI THIS EVE AND EARLY MORNING THU... DRAGGING ANOTHER DEEP SWATH OF MOISTURE AND LIFT. THE RESIDUAL COLDER AIR IN PLACE WILL SPELL ANOTHER MIXTURE OF RAIN/SNOW FOR AT LEAST A COUPLE HOURS LATER THIS EVENING AND OVERNIGHT. THOUGH THERE MAY BE SOME STRONGER BURSTS OF PRECIPITATION...AS SEEN OVER NUMEROUS LOCATIONS THIS AFTERNOON...GROUND TEMPS ARE STILL EXPECTED TO BE WARM ENOUGH TO MITIGATE ANY ACCUMULATION ON PAVED SURFACES WHILE GRASSY AND UNPAVED AREAS MAY SEE UP TO AN INCH OF SNOW ACCUMULATION. AS THE UPR LVL TROF SWINGS THRU AND THE SFC LOW ROTATES AWAY FROM THE AREA...WARMER AIR FROM THE NRN BACKSIDE OF THE SYSTEM WILL SWING INTO SRN-CENTRAL MN AND WRN WI...ALLOWING FOR A CHANGEOVER FROM MIXED WINTRY PRECIPITATION TO ALL RAIN OVERNIGHT INTO DAYBREAK THU MORNING BEFORE ENDING. LOW CLOUDS WILL HANG TOUGH THROUGHOUT THE SHORT-TERM PORTION OF THE FORECAST...THUS MAKING ANY SUNSHINE DIFFICULT TO REALIZE THU. TEMPERATURES WILL HAVE A VERY SMALL DIURNAL RANGE THRU THU AS CURRENT TEMPS ARE EXPECTED TO DROP ROUGHLY 5-10 DEGREES TONIGHT...WHICH WILL BE MAINLY EARLY ON THIS EVE INTO THE EARLY MORNING HOURS BEFORE STARTING TO SLOWLY RISE CLOSE TO DAYBREAK WITH THE PASSAGE OF THE SECONDARY TROF. HIGHS THU WILL THEN BE VERY SIMILAR TO THE HIGHS OF TODAY...IN THE LOW-MID 40S. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 315 PM CDT WED OCT 28 2015 WE/LL ALREADY BE WORKING OUT OF OUR BRIEF TASTE OF WINTER BY THURSDAY NIGHT... WITH THE UPPER TROUGH SHIFTING EAST AND LARGE SCALE FLOW BECOMING ZONAL ACROSS THE NORTHERN TIER OF THE CONUS. WE/LL SEE HEIGHTS RISE BY EARLY NEXT WEEK AS A TROUGH DIGS INTO THE WESTERN CONUS... WHICH SHOULD PUSH TEMPERATURES WELL INTO THE 60S FOR MONDAY INTO TUESDAY. THAT UPPER TROUGH SHOULD REMAIN TO OUR WEST THROUGH MIDWEEK... SO THINGS WILL STAY MILD AND FAIRLY QUIET. THINGS LOOK DRY FROM TOMORROW NIGHT THROUGH THE DAY ON FRIDAY AS THE HIGH PUSHES EAST OF THE AREA. HOWEVER... WARM ADVECTION LOOKS TO BRING PCPN CHANCES BACK INTO THE AREA FRIDAY NIGHT INTO THE DAY ON SATURDAY AS A SOUTHERN STREAM SHORTWAVE MOVES BY TO OUR SOUTHEAST AND A NORTHERN WAVE MOVES THROUGH NORTHERN MINNESOTA. WE SHOULD SEE ANY PCPN END BY SATURDAY EVENING... THEN THINGS LOOK TO BE MILD AND DRY THROUGH TUESDAY BEFORE PCPN CHANCES RETURN AGAIN TUESDAY NIGHT AND WEDNESDAY AS THE WESTERN TROUGH BEGINS TO SLIDE EAST AND WE SEE A SURFACE LOW EMERGE FROM THE HIGH PLAINS. THE GFS AND ECMWF ARE QUITE A BIT DIFFERENT AT THAT POINT... WITH THE GFS MUCH MORE AMPLIFIED AND QUICKER/STRONGER WITH THE SURFACE LOW. SO... AT THIS POINT CAN/T SEE ANY REASON TO GO HIGHER THAN LOW CHANCE POPS ON WEDNESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 656 PM CDT WED OCT 28 2015 THE HRRR AND HOPWRF ARE IN GOOD AGREEMENT ON HANDLING OF PRECIP TONIGHT AS BAND OF PRECIPITATION OVER CENTRAL MN INTO WRN WI EVENTUALLY DROPS DOWN TO EVEN ENCOMPASS RWF. TEMPS HAVE BEEN COLD ENOUGH ACROSS CENTRAL MN AND NW WI TO GET IFR AND EVEN LIFR VSBYS IN SNOW...BUT IS BEGINNING TO LOOK LIKE THOSE CONDITIONS WILL NOT TRAVEL SOUTH WITH THE PRECIP. EXPECT THE WORST CONDITIONS IN THE FIRST 4 OR SO HOURS OF THE TAF...BUT AFTER 4Z...PRECIP RATES SHOULD START TO TAIL OFF...WITH IFR VSBYS BECOMING LESS FREQUENT. PRECIP LOOKS TO DISSIPATE PRETTY QUICK IN THE 8-10Z PERIOD...THOUGH BY THEN TEMPERATURES WILL HAVE WARMED ENOUGH TO SWITCH US BACK TO RAIN. AFTER THAT...ALL GUIDANCE SHOWS STRATUS REMAINING AT ALL TERMINALS THROUGH THE DAY...LIFTING FROM 010-015 IN THE MORNING TO 025-035 IN THE AFTERNOON. CORE OF THE STRONGEST WINDS ALOFT WILL DROP ACROSS THE AREA BETWEEN 3Z AND 10Z. FORECAST SOUNDINGS SHOW THE BOUNDARY LAYER REMAINING WELL MIXED...SO CONFIDENT WE WILL BE ABLE TO TAP THESE WINDS TO GETS GUSTS AS HIGH AS 35 KTS ACROSS WESTERN INTO SOUTHERN MN. KMSP...AS SNOW OVER CENTRAL MN HAS MOVED INTO THE NORTHERN TWIN CITIES METRO...AIRPORTS SUCH AS KMIC AND KANE HAVE BEEN REPORTING MORE RAIN THAN SNOW...SO DO NOT EXPECT THE IFR AND LOWER VSBYS IN SNOW REPORTED NORTH OF THE METRO EARLY TODAY TO MAKE INTO MSP. HAVE A TEMPO GROUP FOR IFR VIS IN SNOW...THOUGH THIS IS BEGINNING TO LOOK LIKE IT MAY HAVE BEEN A BIT OF AN OVER REACTION. AT ANY RATE...THE HIGHEST PRECIP RATES ARE EXPECTED BETWEEN 1Z AND 4Z. CONFIDENCE IS HIGH IN THE REST OF THE TAF THROUGH THURSDAY MORNING. ONLY BIT OF UNCERTAINTY FOR THU AFTERNOON/EVENING IS WHETHER OR NOT IMPROVEMENTS TO VFR CIGS HAPPEN PRIOR TO THE END OF THE TAF PERIOD. /OUTLOOK FOR KMSP/ FRI...VFR. MVFR/-SHRA LIKELY OVERNIGHT. WIND S-SW 10KTS. SAT...CHC MORNING MVFR/SHRA. VFR AFTN. WIND SW 5-10KTS. SUN...VFR. WIND SW 5-10KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. && $$ SHORT TERM...JPC LONG TERM... AVIATION...MPG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
317 PM CDT TUE OCT 27 2015 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 317 PM CDT TUE OCT 27 2015 THE PRIMARY FORECAST CONCERN IN THE SHORT TERM WILL BE GUSTY NORTHWEST WINDS BEHIND A COLD FRONT. FOR THIS EVENING....THE COLD FRONT IS CURRENTLY WORKING SOUTHEAST ACROSS OUR NORTHWEST AND WESTERN ZONES. CLOUDS WITH LIGHT QPF HAVE BEEN ASSOCIATED WITH THE FRONTAL PASSAGE. THE CURRENT KLNX 88D SCAN REVEALS A BROKEN LINE OF SHOWERS/THUNDERSTORM FROM NORTHEASTERN COLORADO NORTH ACROSS DEUEL...WESTERN GARDEN AND EVENTUALLY CENTRAL SHERIDAN COUNTY. NEAR TERM GUIDANCE LOOSELY HAS THE SITUATION RESOLVED...SO WILL GO WITH A GENERAL BLEND OF THE NAM AND LATEST HRRR WITH THE PREVIOUS FORECAST. THE RESULT IS SLIGHT CHANCE TO CHANCE POPS ACROSS THE EASTERN PANHANDLE SOUTH AND EAST THROUGH OUR SOUTHERN ZONES THROUGH THIS EVENING AS THE ACTIVITY GENERALLY DROPS TO THE SOUTHEAST. THERE IS AN ABRUPT END TO PRECIPITATION CHANCES THIS EVENING AS MUCH OF THE ACTIVITY SHOULD BE DIURNALLY DRIVEN. THIS EVENING...WILL NEED TO WATCH A COMPACT PV ANOMALY THAT WILL PUSH SOUTHEAST FROM THE PANHANDLE ACROSS OUR SOUTHERN ZONES. WITH THE FRONTAL PASSAGE INCREASING WINDS ALOFT AND THE PV MAX WOULD ALLOW FOR BREEZY CONDITIONS WELL INTO THE OVERNIGHT HOURS. HOWEVER THE STRONGEST WINDS WILL BEGIN AFTER SUN UP WEDNESDAY WHEN A 100KT+ H5 JET DIVES SOUTH FROM THE NORTHERN PLAINS AND COMBINES WITH SUBSTANTIAL SFC PRESSURE FALLS...AND SOLID MIXING AS LOW AND MID LEVEL LAPSE RATES INCREASE. THERE/S POTENTIAL OF GUSTS IN EXCESS OF 45MPH ACROSS NORTH CENTRAL NEBRASKA...AND IF WE MIX TO THE FULL POTENTIAL /ABOVE H7/...50MPH WOULD BE POSSIBLE. ATTM WE FEEL THE 45 MPH GUSTS SHOULD BE THE UPPER LIMIT. THE WIND/MIXING OVERNIGHT WILL OFFSET THE RADIATIONAL COOLING AND POST FRONTAL CAA...BUT STILL...LOWS ARE FORECAST TO FALL INTO THE UPPER 20S /NORTHWEST/...30S ELSEWHERE. SOME OF THE GUIDANCE INDICATES THE ATMOSPHERE PARTIALLY DECOUPLING NEAR DAWN...IF THIS OCCURS...TEMPERATURES MAY BE COOLER. HIGHS ON WEDNESDAY ARE A PRODUCT OF THE MET/MAV GUIDANCE AND THE PREVIOUS FORECAST. PLENTIFUL CAA WILL PROMOTE HIGHS OF ONLY THE UPPER 40S FOR THE NORTH...NEAR 60 OVER THE SOUTH. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 317 PM CDT TUE OCT 27 2015 A MODIFIED CANADIAN AIRMASS WILL BE IN PLACE ACROSS THE NRN AND CNTRL PLAINS WEDNESDAY NIGHT AS SURFACE HIGH PRESSURE SETTLES OVERHEAD. MODEL GUIDANCE CONTINUES TO SUPPORT LOWS IN THE UPPER TEENS ACROSS THE NWRN SANDHILLS...LOWER 20S CENTRAL SANDHILLS...TO THE UPPER 20S FAR NERN ZONES. HIGHS ON THURSDAY WILL BE AFFECTED BY CANADIAN AIRMASS AS THE SURFACE HIGH DRIFTS EASTWARD AND A LIGHT SOUTHERLY RETURN FLOW BEGINS. WITH FULL SUNSHINE AND LIMITED MIXING...HIGHS NEAR PREVIOUS FCST FROM NEAR 55 SWRN NEBR TO NEAR 50 IN THE NORTHEAST. A PROGRESSIVE POSITIVELY TILTED SYSTEM WILL APPROACH THURSDAY NIGHT WITH A MOISTURE RETURN FROM TEXAS INTO KANSAS. A 20 TO 30 PERCENT CHANCE FOR SHOWERS FRIDAY MORNING...WITH 30 TO 50 POPS FRIDAY AFTN EAST OF AINSWORTH THROUGH MULLEN AND OGALLALA. PREFERRED THE SLOWER TIMING OF THE 12Z GFS RUN OVER THE NAM. CHC POPS INTO FRIDAY NIGHT ACROSS THE SOUTHEAST AS UPPER TROUGH EXITS. DRY WITH A WARMING TREND SATURDAY THROUGH MONDAY. WARM AIR ADVECTION TO OCCUR AS AN UPPER TROUGH DIGS INTO THE PAC NW SUNDAY/MONDAY WITH HIGHS AROUND 70 EACH DAY. A WEAK COLD FRONT MONDAY NIGHT WITH SLIGHTLY COOLER HIGHS TUESDAY IN THE UPPER 50S TO LOWER 60S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1234 PM CDT TUE OCT 27 2015 A COLD FRONT WILL PROMOTE GUSTY CONDITIONS THROUGH THE TAF FORECAST PERIOD FOR ALL WEST CENTRAL NEBRASKA TERMINALS. TIMING OF THE FRONT IS SLATED TO ARRIVE AT KVTN BEFORE 21Z...AND CROSS THE KLBF TERMINAL BY 00Z THIS EVENING. MODEL GUIDANCE WAS DEEMED A BIT LIGHT ON SPEEDS...ESPECIALLY OVERNIGHT TONIGHT AND ON WEDNESDAY...THUS SUBSEQUENT AVIATION FORECASTS MAY NUDGE SPEEDS HIGHER...BUT FOR NOW GUSTS IN EXCESS OF 25 KTS ARE POSSIBLE. STRATUS IS ACCOMPANYING THE FRONTAL PASSAGE...MVFR CEILINGS ARE EXPECTED WITH THE POSSIBILITY OF LIGHT QPF. BUT AS OF NOW...THE PROBABILITY OF SHOWERS IMPACTING EITHER KLBF OR KVTN IS LOW /LESS THAN 30 PERCENT/. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...JACOBS LONG TERM...ROBERG AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
700 PM EDT TUE OCT 27 2015 .SYNOPSIS...A SERIES OF DISTURBANCES WILL PASS OVER THE AREA THROUGH WEDNESDAY... AS A WARM FRONT MOVES GRADUALLY TOWARD THE NORTHWEST AND NORTH THROUGH THE REGION. THE PASSAGE OF A COLD FRONT THURSDAY WILL USHER CANADIAN HIGH PRESSURE INTO THE EASTERN STATES FOR FRIDAY AND SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 700 PM TUESDAY... UPDATE...AN INITIAL WEAK MID LEVEL DISTURBANCE IS LIFTING ACROSS THE NORTHERN TIER OF THE AREA EARLY TONIGHT WITH DIMINISHING RAIN COVERAGE ACROSS THE SOUTH. THIS LULL LOOKS TO BE SHORT LIVED... HOWEVER...AS ANOTHER WEAK DISTURBANCE...BARELY VISIBLE ON H2O VAPOR IMAGERY BUT WELL-DEFINED ON RAP AND GFS...WILL BE LIFTING NORTH ACROSS THE AREA OVERNIGHT. AS SUCH...ONGOING ~100 POPS LOOK GOOD. SIMILARLY... THERE HAS BEEN A SLIGHT BUMP UPWARDS IN THE TEMPS ACROSS THE NORTHWEST OVER THE PAST COUPLE OF HOURS...SUPPORTING THE VERY GRADUAL RISE EXPECTED OVERNIGHT ACROSS THE AREA AS WARM AIR ADVECTION ALOFT CONTINUES TO PECK AWAY AT THE COOL AIRMASS. CLASSICAL COLD AIR DAMMING OCCURRING WITH A PARENT HIGH (1035MB) SLOWLY DRIFTING OFFSHORE OF NEW ENGLAND. MEANWHILE EAST-SELY FLOW JUST A COUPLE THOUSAND FEET OFF THE SURFACE WAS STRENGTHENING IN RESPONSE TO THE APPROACH OF A MID-UPPER LEVEL S/W OR SHEAR AXIS. THIS OVERRUNNING SET-UP WILL MAINTAIN PERIODS OF RAIN OVER CENTRAL NC THROUGH THE EVENING HOURS. AS SHEAR AXIS LIFTS NEWD AND EXITS OUR REGION AFTER MIDNIGHT...RAIN COVERAGE EXPECTED TO BECOME MORE SPOTTY AND LIGHTER IN INTENSITY. A COASTAL TROUGH WAS ANALYZED NEAR OR JUST OFFSHORE OF THE NC COAST AT 19Z. THIS FEATURE WILL SLOWLY DRIFT INLAND OVERNIGHT. MODEL GUIDANCE SUGGEST THIS FEATURE WORKING ITS WAY THROUGH OUR REGION LATE TONIGHT THROUGH WEDNESDAY MORNING. THIS SUGGEST TEMPS HOLDING STEADY OVER MOST OF CENTRAL NC THROUGH THE EVENING HOURS THEN SLOWLY RISING...ESPECIALLY EAST OF THE HIGHWAY 1 CORRIDOR AFTER MIDNIGHT. BY DAYBREAK...MOST LOCATIONS EXCLUDING THE NW PIEDMONT SHOULD BE AT OR ABOVE 60 DEGREES. WHILE VISIBILITIES SHOULD BE IN THE 2-5 MILE RANGE DUE TO RAIN AND/OR LIGHT FOG...ATMOSPHERE APPEARS TO WELL MIXED TO CAUSE AREAS OF DENSE FOG TO DEVELOP. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 345 PM TUESDAY... WEDNESDAY...AN AMPLIFYING UPEPR LEVEL TROUGH EXTENDING FROM THE GREAT LAKES INTO THE TN VALLEY WILL SEND A SERIES OF S/W INTO CENTRAL NC WEDNESDAY AND WEDNESDAY NIGHT. THE APPROACH OF THIS SYSTEM WILL AID TO STRENGTHEN THE LOW-MID LEVEL FLOW OUT OF THE SOUTH OVER CENTRAL NC. THE NEAR SURFACE FLOW WILL ADVECT A WARM HUMID AIR MASS INTO OUR REGION. THE STRENGTHENING FLOW WILL INCREASE THE 0-6KM BULK SHEAR INTO THE 35-45KT RANGE. THIS AMOUNT OF SHEAR COUPLED WITH THE VEERING LOW LEVEL FLOW (RESIDUAL EFFECT OF THE CAD AIR MASS IN THE PIEDMONT) SUGGEST LOW LEVEL HELICITY VALUES NEAR THE FAVORABLE PARAMETERS FOR ROTATING CELLS. HOWEVER... THE LOWER HALF OF THE ATMOSPHERE MAY NOT BE BUOYANT ENOUGH TO GENERATE STORMS OF SUFFICIENT DEPTH AS LOW LEVEL INSTABILITY APPEARS TO BE LACKING. THAT BEING SAID...THE MODEL TREND HAS BEEN TO INCREASE THE INSTABILITY WITH EACH SUCCESSIVE RUN SUCH THAT THE 12Z GFS MUCAPE VALUES REACH 1200-1400 J/KG OVER PORTIONS OF THE PIEDMONT AND COASTAL PLAIN WEDNESDAY AFTERNOON AND MLCAPE 400-600J/KG. IF THE MODEL TREND CONTINUES AND IF PEEKS OF SUN OCCUR LATE WEDNESDAY MORNING-AFTERNOON NEAR OR ADJACENT TO OUR REGION...ESPECIALLY SOUTH OF OUR AREA...THEN THE THREAT FOR SEVERE STORMS WILL INCREASE. PLAN TO HAVE POPS IN THE LIKELY TO CATEGORICAL EARLY WEDNESDAY...THEN HIGH CHANCE-LIKELY CATEGORIES WEDNESDAY AFTERNOON AS PRECIP CHARACTER BECOME MORE CONVECTIVE. HIGH TEMPS DEPENDENT UPON DEGREE OF WARM AIR ADVECTION (SOONER THE BETTER). HAVE MAX TEMPS VARYING FROM THE MID-UPPER 60S NW (WHERE RESIDUAL CAD AIR MASS WILL BE LATE TO ERODE) TO THE MID 70S SE. IF ANY BREAKS IN THE OVERCAST OCCUR (SANDHILLS AND COASTAL PLAIN) THEN MAX TEMPS MAY END UP 3-4 DEGREES WARMER. PRE FRONTAL TROUGH AHEAD OF A COLD FRONT WILL CROSS CENTRAL NC LATE WEDNESDAY EVENING INTO THE OVERNIGHT HOURS. THE PASSAGE OF THIS FEATURE WILL DIMINISH CONVECTIVE THREAT. SHOULD SEE POPS DECREASE IN THE WEST PRIOR TO MIDNIGHT...AND IN THE COASTAL PLAIN BY THE OVERNIGHT HOURS. && .LONG TERM /THURSDAY THROUGH TUESDAY/... AS OF 135 PM TUESDAY... THU/THU NIGHT: THE SURFACE FRONT/WIND SHIFT WILL HAVE PUSHED EAST OF THE FORECAST AREA WITH STRONG DRYING AND SINKING AIR EXPECTED ABOVE 850 MB... ALTHOUGH THE TRULY COLDER AND DRIER SURFACE AIR WILL NOT ARRIVE UNTIL THU NIGHT. LOW LEVEL THICKNESSES REMAIN WELL ABOVE NORMAL DURING THE DAY WITH A WESTERLY DOWNSLOPE LOW LEVEL WIND COMPONENT... SO EXPECT ABOVE-NORMAL HIGHS FROM 71-78. ISOLATED SHALLOW SHOWERS ARE POSSIBLE WITH SECONDARY FRONTAL PASSAGE THU NIGHT... BUT WITH EXPECTED VERY LOW COVERAGE AND LOW QPF RESULTING FROM THE FALLING PW... WILL MAINTAIN A DRY FORECAST... ALTHOUGH FORECAST SOUNDINGS SHOW SUFFICIENT MOISTURE AT 850-800 MB ALONG THE FRONTAL ZONE ALOFT TO SUPPORT PARTLY CLOUDY SKIES. LOWS FROM 43 NW TO 51 SE AS THICKNESSES DROP BELOW NORMAL. FRI-TUE: DRY WITH PLENTY OF SUNSHINE FRI/SAT. SURFACE HIGH PRESSURE WILL BUILD OVER THE OH VALLEY FRI... PUSHING TO THE MIDATLANTIC REGION BY SAT AND OFF THE COAST SAT NIGHT. A BAGGY AND POSITIVELY TILTED MID LEVEL TROUGH AXIS WILL PUSH EAST OFF THE COAST FRI AFTERNOON FOLLOWED BY RISING HEIGHTS... A RESULT OF A POTENT LONGWAVE TROUGH FROM THE CENTRAL PLAINS TO THE DESERT SW AND NRN MEXICO FORCING DOWNSTREAM RIDGING OVER FL AND THE SE STATES. CLOUDS SHOULD INCREASE OVER NC STARTING LATE SAT AS THE SW TROUGH HEADS EASTWARD... INCREASING THE SWRLY STEERING FLOW AND PASSAGE OF PERTURBATIONS FROM THE WRN GULF INTO THE SRN APPALACHIANS. THE GFS IS A BIT WEAKER AND OVER 12 HRS FASTER THAN THE ECMWF IN LIFTING THIS MID LEVEL LOW TO THE E THEN NE THROUGH THE MID MISS VALLEY INTO THE OH VALLEY. THE OP ECMWF APPEARS TO HAVE BETTER AGREEMENT WITH ITS ENS MEAN THAN THE GFS... AND THE GEFS MEAN ACTUALLY MORE RESEMBLES THE OP ECMWF THAN THE GFS. WITH A LEAN TOWARD THE ECMWF...WILL GO WITH THICKENING CLOUD COVER SUN BUT HOLD OFF ON CHANCE POPS UNTIL SUN NIGHT... LIKELY LASTING INTO MON/TUE (WITH A DROPOFF IN CONFIDENCE) WITH EXPECTATIONS OF A STEADY STREAM OF ATLANTIC AND GULF MOISTURE IN THE LOW AND MID LEVELS... AND SURFACE FRONTAL ZONE APPROACHING FROM THE NORTH AND WEST. THICKNESSES SHOULD START OFF BELOW NORMAL SAT AND RISE ABOVE NORMAL BY LATE SUN... HOLDING ABOVE NORMAL MON/TUE SOUTHEAST OF THE FRONTAL ZONE. -GIH && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 152 PM TUESDAY... VERY HIGH PROBABILITY THAT LIFR/IFR CONDITIONS WILL PREVAIL ACROSS CENTRAL NC THROUGH WEDNESDAY MORNING AS A STOUT LOW LEVEL EASTERLY FLOW PUMPS MOIST AIR INTO THE REGION. A SERIES OF UPPER LEVEL DISTURBANCES WILL CAUSE PERIODS OF LIGHT-MODERATE RAIN WELL INTO THE OVERNIGHT HOURS WITH THE RAIN BECOMING MORE SHOWERY IN CHARACTER...ESPECIALLY ACROSS THE SANDHILLS AND COASTAL PLAIN...BY EARLY WEDNESDAY. A NELY SFC FLOW WILL QUICKLY VEER TO A SELY FLOW JUST ABOVE THE SURFACE AND INCREASE CLOSE TO 40KTS. THIS WILL RESULT IN MARGINAL LOW LEVEL WIND SHEAR CONDITIONS. THIS CONDITION EXPECTED TO BE GREATEST AND PERSIST THE LONGEST IN VICINITY OF THE TRIAD TAF SITES. THE ATMOSPHERE IS EXPECTED TO BECOME CONDITIONALLY UNSTABLE WEDNESDAY-WEDNESDAY AHEAD OF A COLD FRONT. THIS SET-UP SHOULD INITIATE AND SUSTAIN BROKEN BANDS OF CONVECTION OVER CENTRAL NC FROM MID-LATE MORNING THROUGH THE EVENING HOURS. A FEW STORMS WILL HAVE THE POTENTIAL TO BECOME SEVERE...POSSIBLY PRODUCING DAMAGING WIND GUSTS OR AN ISOLATED TORNADO. MAIN LIMITATION TO THE DEVELOPMENT OF SEVERE STORMS WILL BE THE LACK OF SUFFICIENT LOW LEVEL BUOYANCY/INSTABILITY. THE FRONT WILL CROSS CENTRAL NC LATE WEDNESDAY NIGHT INTO THURSDAY MORNING. DRIER AIR WILL ADVECT INTO CENTRAL NC...AIDING TO LIFT AND DISSIPATE THE CLOUD COVERAGE...INITIATING A PERIOD OF VFR CONDITIONS THAT SHOULD PERSIST THROUGH SATURDAY. AN APPROACHING FRONTAL SYSTEM MAY BRING A PERIOD OF ADVERSE WEATHER CONDITIONS TO CENTRAL NC BY LATE SUNDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...26/HARTFIELD NEAR TERM...WSS/MLM SHORT TERM...WSS LONG TERM...HARTFIELD AVIATION...WSS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
315 PM EDT TUE OCT 27 2015 .SYNOPSIS... INTERMITTENT RAIN WILL CONTINUE ACROSS THE CAROLINAS THROUGH THIS EVENING AS LOW PRESSURE OVER THE LOWER MISSISSIPPI VALLEY MOVES SLOWLY NORTH. A WARM FRONT WILL LIFT NORTH LATE TONIGHT WITH THUNDERSTORMS POSSIBLE ON WEDNESDAY. DRYING WILL OCCUR EARLY THURSDAY FOLLOWED BY A COLD FRONT LATE IN THE DAY. DRY HIGH PRESSURE WILL FOLLOW FOR FRIDAY AND THE UPCOMING WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 2 PM TUESDAY...RADAR INDICATING AREAS OF LIGHT RAIN WITH A FEW POCKETS OF SLIGHTLY HEAVIER RAIN ACROSS THE AREA. THE HEAVIEST RAIN EARLY THIS AFTERNOON WAS OVER THE TIP OF CAPE FEAR WHERE STRONG ON SHORE WINDS WERE PUSHING SOME MORE CONVECTIVE TYPE PCP TOWARD THE COAST...THEN MOVING ON SHORE AS LIGHT TO MODERATE RAIN. CLOUDY...COOL AND DAMP WEATHER WILL PERSIST WITH PERIODS OF RAIN THROUGH THIS AFTERNOON. FOR THE MOST PART...THE HIGH PRESSURE WEDGE AND EVAPORATIVE COOLING WERE KEEPING TEMPERATURES JUST BELOW 60 WEST OF I95 AND INTO THE MID 60S ALONG THE COAST. HIGH PRESSURE WEDGE EVIDENT WITH N-NE WINDS AT THE SURFACE. VAD WIND PROFILES SHOWING STRONG EASTERLY FLOW UP TO 35 KTS THROUGH THE LOWER LEVELS VEERING TO MORE SOUTHERLY IN THE MID TO UPPER LEVELS. THIS WILL KEEP PERSISTENT MOIST HELP WITH ISENTROPIC LIFT OVER INLAND AREAS WHILE BETTER CONVERGENCE AND CONVECTIVE TYPE PCP HOLDS OFF SHORE. OVERALL A STRONG MOISTURE TRANSPORT OFF THE ATLANTIC WILL PERSIST THROUGH TONIGHT...WITH A CONTINUED VEERING PROFILE OF LOW- LEVEL WINDS WORKING DOWN TO THE SFC EVENTUALLY OVERNIGHT AS WARM FRONT MOVES INLAND AND NORTH. THE BULK OF RAINFALL WILL REMAIN STRATIFORM IN NATURE TODAY...TRANSITIONING TO A SHOWERY CHARACTER TONIGHT AS A WARM FRONT SPREADS MILD AIR INLAND. EXPECT SOME SPOTS TO SEE QPF TOTALS UP TO 1.25 INCHES UP THROUGH DAYBREAK WEDNESDAY. MIN TEMPS WILL BE A BIT TRICKY AS WARM FRONT WORKS ITS WAY INLAND LATE TONIGHT...BUT TEMPS WILL NOT SHOW MUCH MOVEMENT INTO TONIGHT BUT RATHER THAN DROP TOO MUCH THERE WILL BE A SLIGHT RISE AS WARM FRONT MOVES INLAND AND NORTH OVERNIGHT. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 PM TUESDAY...H5 LOW DROPPING TOWARD THE MIDWEST WEDNESDAY WILL DIRECT A SHORT WAVE TOWARD THE CAROLINAS BY WEDNESDAY NIGHT ALLOWING A SURFACE TROUGH/WEAK FRONT TO MOVE BY. THE TROUGH/WEAK FRONT WILL EFFECTIVELY PUSH THE DEEPER MOISTURE/HIGHER PRECIPITABLE WATER OFF THE COAST DURING THAT SAME TIME FRAME BRINGING RAIN CHANCES TO AN END. IN THE MEANTIME...MARGINAL SURFACE BASED INSTABILITY AND CAPE AROUND 1000 J/KG WILL SUPPORT A FEW TSTMS WEDNESDAY...WITH AN ISOLATED SVR THREAT. THE PRECIPITABLE WATER ATTEMPTS TO RECOVER AHEAD OF ANOTHER WEAK COLD FRONT THURSDAY BUT WITH DOWNSLOPE FLOW AND INCREASED STABILITY NO PLAN TO INCLUDE POPS AT THIS TIME FOR THURSDAY. A CONTINUATION OF ABOVE NORMAL TEMPERATURES IS EXPECTED WEDNESDAY AND THURSDAY WITH COLD AIR ADVECTION LACKING. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 3 PM TUESDAY...DRY DOWNSLOPING MID LEVEL FLOW ON FRIDAY WHILE HIGH PRESSURE BUILDS IN FROM POINTS NORTH AND WEST. ON SATURDAY THE RIDGE AXIS CROSSES THE AREA BOTH SURFACE AND ALOFT. THE PATTERN IS QUITE PROGRESSIVE SO THE AFOREMENTIONED FEATURES END UP OFF THE COAST ON SUNDAY. THIS WILL SET THE STAGE FOR MOISTURE AND TO A LESSER EXTENT WARM ADVECTION. THE OFFSHORE RIDGE APPEARS TO HAVE SOME STRENGTH TO IT AS MODELS SHOW THE NEXT POTENT UPPER TROUGH APPROACH FROM THE WEST GETTING SHUNTED NORTHEASTWARD. THIS IS MAKING FOR A LITTLE UNCERTAINTY REGARDING THE TIMING OF THE RAIN CHANCES BROUGHT BY THIS SYSTEM AS TYPICALLY IN SUCH A SETUP GUIDANCE IS TOO FAST. FOR NOW THE BEST BET STILL LOOKS LIKE MONDAY. BY TUESDAY THE TROUGH EVEN LOSES MOST OF ITS IDENTITY AS VERY BROAD RIDGING DEVELOPS ACROSS MUCH OF THE EASTERN U.S. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 18Z...WEDGE STILL HANGING IN THERE AND EXPECTED TO DO SO FOR MUCH OF THE EVENING. NORTHEAST WINDS WILL SLOWLY VEER TO THE EAST THIS EVENING...BECOMING SOUTHEAST DURING THE OVERNIGHT HOURS. AM LEANING TOWARDS THE HRRR IN THE NEAR TERM AS IT HAS BEEN PRETTY CONSISTENT IN BRINGING IN HEAVIER RAIN ALONG THE COAST THIS EVENING...PARTICULARLY AT ILM. OVERNIGHT EXPECT IFR INLAND WITH PREDOMINATELY MVFR ALONG THE COAST...CONFIDENCE IS MODERATE. WEDNESDAY...THINGS BECOME MORE UNSTABLE IN THE WARM SECTOR WITH CONVECTION EXPECTED TO BREAK OUT AT ANY TIME. COULD BE SOME DECENT STORMS IF WE GET SOME GOOD HEATING. GUSTY SOUTHERLY FLOW WITH DEWPOINTS IN THE MID TO UPPER 60S. EXTENDED OUTLOOK...BECOMING VFR WEDNESDAY NIGHT...CONTINUING THROUGH SATURDAY. LOW CONFIDENCE FOR SHOWERS SUNDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 2 PM TUESDAY...A SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH TONIGHT. SEAS UP TO 6 TO 8 FT WITH WINDS NE UP TO 25 KTS VEERING AROUND SLIGHTLY TO A MORE EASTERLY DIRECTION AND DIMINISHING IN INTENSITY THROUGH THIS AFTERNOON. MOST OF THE WAVE ENERGY WILL BE TIED TO WAVE PERIODS OF 7 TO 8 SECONDS. WINDS WILL DIMINISH AND VEER AROUND FURTHER THROUGH TONIGHT AS A WARM FRONT PUSHES TOWARD THE COAST AND INLAND WITH MAIN FOCUS OF SCA ON SEAS REMAINING HIGH DUE TO ON SHORE PUSH. AS A WARM FRONT MOVES FARTHER INLAND THROUGH TONIGHT...WINDS WILL COME AROUND TO THE E TO SE. INCREASED CONVERGENCE/SHEAR ALONG THIS BOUNDARY WILL PRODUCE ISOLATED TSTMS. SMALL CRAFT ADVISORY CONDITIONS WILL PERSIST THROUGH THE NEAR TERM AND BEYOND. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 PM TUESDAY...SOUTHERLY FETCH WEDNESDAY WILL TURN TO AN OFFSHORE DIRECTION LATE WEDNESDAY NIGHT IN THE WAKE OF A SURFACE TROUGH/WEAK FRONT. COLD AIR ADVECTION IS LACKING BEHIND THE TROUGH/FRONT AND EXPECT THE FLOW TO BACK TO A WEST TO SOUTHWEST DIRECTION BY THURSDAY NIGHT WITH ANOTHER WEAK FRONT ADVANCING ACROSS THE WATERS VERY LATE. SEAS WILL BE HIGHEST ACROSS THE AREA WATERS DURING WEDNESDAY...THEN THE RANGE WILL INCREASE FROM NEARSHORE TO THE OUTER COASTAL WATERS AS THE FLOW BECOMES OFFSHORE. SMALL CRAFT ADVISORY WILL CONTINUE THROUGH WEDNESDAY. LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 3 PM TUESDAY...WINDS VEERING FROM NORTHERLY TO NORTHEASTERLY AS FRIDAY PROGRESSES WITH HIGH PRESSURE MOVING EAST AND PASSING US BY WELL TO THE NORTH. THESE NORTHEASTERLY WINDS WILL CONTINUE INTO SATURDAY AND SLACKEN IN SPEED DUE TO THE HIGH EXTENDING A RIDGE AXIS DOWN INTO THE CAROLINAS AND ADJACENT WATERS EASING THE PRESSURE GRADIENT. FURTHER VEERING TO SE OR PERHAPS EVEN SW THEN SLATED FOR SUNDAY AS THE HIGH PROGRESSES OFFSHORE AND PERHAPS A WEAK PIEDMONT TROUGH DEVELOPS. && .TIDES/COASTAL FLOODING... AS OF 3 PM TUESDAY...COASTAL FLOOD ADVISORY IN EFFECT FOR LOWER CAPE FEAR RIVER AND ALL BEACHES. MINOR COASTAL FLOODING POSSIBLE AGAIN DURING HIGH TIDE THIS EVENING WHICH WILL OCCUR AROUND 8PM THIS EVENING ALONG THE BEACHES AND CLOSE TO 1030 PM FOR DOWNTOWN WILMINGTON. THE GREATEST TIDE DEPARTURE OCCURS THE DAY AFTER FULL MOON AND WITH SLIGHTLY HIGHER ASTRONOMICAL TIDES COUPLED WITH ONSHORE FLOW HAVE OPTED TO RAISE AS COASTAL FLOOD WATCH FOR GEORGETOWN...HORRY... BRUNSWICK.... NEW HANOVER AND PENDER COUNTIES FOR WEDNESDAY MORNING. A COASTAL FLOOD ADVISORY SHOULD COVER THE IMPACTS ALONG THE LOWER CAPE FEAR RIVER TOMORROW MORNING. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...COASTAL FLOOD WATCH WEDNESDAY MORNING FOR SCZ054-056. NC...COASTAL FLOOD WATCH WEDNESDAY MORNING FOR NCZ106-108-110. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR AMZ254-256. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT WEDNESDAY NIGHT FOR AMZ250-252. && $$ NEAR TERM...RGZ SHORT TERM...SRP LONG TERM...MBB AVIATION...DL/RGZ TIDES/COASTAL FLOODING...SRP/RGZ
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
231 PM EDT TUE OCT 27 2015 .SYNOPSIS... INTERMITTENT RAIN WILL CONTINUE ACROSS THE CAROLINAS THROUGH THIS EVENING AS LOW PRESSURE OVER THE GULF COAST MOVES SLOWLY NORTH. A WARM FRONT WILL LIFT NORTH LATE TONIGHT WITH THUNDERSTORMS POSSIBLE ON WEDNESDAY. DRYING WILL OCCUR EARLY THURSDAY FOLLOWED BY A COLD FRONT LATE IN THE DAY. DRY HIGH PRESSURE WILL FOLLOW FOR FRIDAY AND THE UPCOMING WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 200 PM TUESDAY...RADAR INDICATING AREAS OF LIGHT RAIN WITH A FEW POCKETS OF SLIGHTLY HEAVIER RAIN ACROSS THE AREA. THE HEAVIEST RAIN EARLY THIS AFTERNOON WAS OVER THE TIP OF CAPE FEAR WHERE STRONG ON SHORE WINDS WERE PUSHING SOME MORE CONVECTIVE TYPE PCP TOWARD THE COAST...THEN MOVING ON SHORE AS LIGHT TO MODERATE RAIN. CLOUDY...COOL AND DAMP WEATHER WILL PERSIST WITH PERIODS OF RAIN THROUGH THIS AFTERNOON. FOR THE MOST PART...THE HIGH PRESSURE WEDGE AND EVAPORATIVE COOLING WERE KEEPING TEMPERATURES JUST BELOW 60 WEST OF I95 AND INTO THE MID 60S ALONG THE COAST. HIGH PRESSURE WEDGE EVIDENT WITH N-NE WINDS AT THE SURFACE. VAD WIND PROFILES SHOWING STRONG EASTERLY FLOW UP TO 35 KTS THROUGH THE LOWER LEVELS VEERING TO MORE SOUTHERLY IN THE MID TO UPPER LEVELS. THIS WILL KEEP PERSISTENT MOIST HELP WITH ISENTROPIC LIFT OVER INLAND AREAS WHILE BETTER CONVERGENCE AND CONVECTIVE TYPE PCP HOLDS OFF SHORE. OVERALL A STRONG MOISTURE TRANSPORT OFF THE ATLANTIC WILL PERSIST THROUGH TONIGHT...WITH A CONTINUED VEERING PROFILE OF LOW- LEVEL WINDS WORKING DOWN TO THE SFC EVENTUALLY OVERNIGHT AS WARM FRONT MOVES INLAND AND NORTH. THE BULK OF RAINFALL WILL REMAIN STRATIFORM IN NATURE TODAY...TRANSITIONING TO A SHOWERY CHARACTER TONIGHT AS A WARM FRONT SPREADS MILD AIR INLAND. EXPECT SOME SPOTS TO SEE QPF TOTALS UP TO 1.25 INCHES UP THROUGH DAYBREAK WEDNESDAY. MIN TEMPS WILL BE A BIT TRICKY AS WARM FRONT WORKS ITS WAY INLAND LATE TONIGHT...BUT TEMPS WILL NOT SHOW MUCH MOVEMENT INTO TONIGHT BUT RATHER THAN DROP TOO MUCH THERE WILL BE A SLIGHT RISE AS WARM FRONT MOVES INLAND AND NORTH OVERNIGHT. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 330 AM TUESDAY...ACTIVE WEATHER WEDNESDAY BEHIND A WARM FRONT...BEFORE DRYING OCCURS THURSDAY. THE SHORT TERM WILL FEATURE ABOVE NORMAL TEMPERATURES. WARM FRONT WILL BE LIFTING NORTH...OR POSSIBLY COMPLETELY THROUGH...THE CWA TO START THE PERIOD. AS THIS FRONT LIFTS NORTHWARD...DRAPED FROM A LARGE CYCLONE ACROSS THE GREAT LAKES...STRONG WAA WILL DEVELOP. FORECAST SOUNDINGS SUGGEST A LLJ OF 30-40 KTS AT THE TOP OF THE PBL WEDNESDAY AFTN...THIS DRIVING BOTH THE WARM ADVECTION AND POTENTIAL CONVECTION DURING THE DAY. ALTHOUGH FORCING IS SOMEWHAT LIMITED DURING WEDNESDAY...SCATTERED TO WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED IN AN ENVIRONMENT CHARACTERIZED BY PWATS OF 1.75 INCHES AND MLCAPE OF 500-1000 J/KG. LAPSE RATES ARE NOT TREMENDOUSLY STEEP...AND DRY AIR ABOVE 600MB WILL ALSO BE A LIMITING FACTOR...BUT THUNDERSTORMS WITH GUSTY WINDS ARE LIKELY ACROSS THE AREA. THESE STRONG WINDS COULD POTENTIALLY MIX DOWN AS AN ISOLATED DAMAGING WIND GUST AS WELL...AND SPC HAS PLACED THE AREA IN A MARGINAL RISK IN THE SWODY2. POTENT VORT LOBE SWINGS ACROSS THE AREA LATE WEDNESDAY NIGHT AND INTO THURSDAY...CAUSING RAPID DRYING OF THE COLUMN AS EVIDENCED BY PWATS FALLING TO 0.75 INCHES OR LESS. THE COLD FRONT AND ASSOCIATED COLD ADVECTION LAGS THE UPPER VORT HOWEVER...SO THURSDAY WILL LIKELY BE A WARM AND BECOMING MOSTLY SUNNY DAY BEFORE THE FROPA OCCURS LATE. TEMPS WEDNESDAY WILL BE WARM EVEN WITH CLOUDS AND CONVECTION ON THE STRONG WAA...RISING INTO THE UPPER 70S OR EVEN LOW 80S SOUTHERN ZONES...MID 70S ACROSS THE NORTH. MID TO UPPER 70S WILL AGAIN BE EXPECTED ON THURSDAY. MINS WEDNESDAY NIGHT WILL BE A SOLID 10-15 DEGREES ABOVE NORMAL...DROPPING ONLY TO 60-65...COOLEST INLAND...WITH MORE SEASONABLE LOWS EXPECTED THURSDAY NIGHT AFTER COLD FROPA. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 330 AM TUESDAY...BEAUTIFUL FALL WEATHER FOR THE FIRST HALF OF THE EXTENDED BEHIND A COLD FRONT WHICH WILL BE OFFSHORE FRIDAY MORNING. STRONG CAA WILL KEEP TEMPS SLIGHTLY BELOW CLIMO BOTH FRIDAY AND SATURDAY...BUT WITH ABUNDANT SUNSHINE IN AN EXCEEDINGLY DRY COLUMN...IT WILL BE NEARLY PERFECT FOR THE TIME OF YEAR. HALLOWEEN FESTIVITIES SATURDAY NIGHT WILL BE COOL BUT DRY...WITH ONLY SOME MID- LEVEL CLOUDINESS BEGINNING TO INCREASE LATE SAT NIGHT. GUIDANCE HAS SLOWED PROGRESS OF A STORM SYSTEM AND ITS COLD FRONT FOR THE END OF THE PERIOD...AND NOW MUCH OF SUNDAY APPEARS TO BE DRY AND WARMER AS RETURN FLOW DEVELOPS...BUT WITH INCREASED CLOUDINESS. A COLD FRONT WILL APPROACH ON MONDAY WITH INCREASING SHOWER AND TSTM CHANCES...BUT TEMPS ARE FORECAST TO REMAIN ABOVE CLIMO THROUGH THE END OF THE EXTENDED. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 18Z...WEDGE STILL HANGING IN THERE AND EXPECTED TO DO SO FOR MUCH OF THE EVENING. NORTHEAST WINDS WILL SLOWLY VEER TO THE EAST THIS EVENING...BECOMING SOUTHEAST DURING THE OVERNIGHT HOURS. AM LEANING TOWARDS THE HRRR IN THE NEAR TERM AS IT HAS BEEN PRETTY CONSISTENT IN BRINGING IN HEAVIER RAIN ALONG THE COAST THIS EVENING...PARTICULARLY AT ILM. OVERNIGHT EXPECT IFR INLAND WITH PREDOMINATELY MVFR ALONG THE COAST...CONFIDENCE IS MODERATE. WEDNESDAY...THINGS BECOME MORE UNSTABLE IN THE WARM SECTOR WITH CONVECTION EXPECTED TO BREAK OUT AT ANY TIME. COULD BE SOME DECENT STORMS IF WE GET SOME GOOD HEATING. GUSTY SOUTHERLY FLOW WITH DEWPOINTS IN THE MID TO UPPER 60S. EXTENDED OUTLOOK...BECOMING VFR WEDNESDAY NIGHT...CONTINUING THROUGH SATURDAY. LOW CONFIDENCE FOR SHOWERS SUNDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 200 PM TUESDAY...A SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH TONIGHT. SEAS UP TO 6 TO 8 FT WITH WINDS NE UP TO 25 KTS VEERING AROUND SLIGHTLY TO A MORE EASTERLY DIRECTION AND DIMINISHING IN INTENSITY THROUGH THIS AFTERNOON. MOST OF THE WAVE ENERGY WILL BE TIED TO WAVE PERIODS OF 7 TO 8 SECONDS. WINDS WILL DIMINISH AND VEER AROUND FURTHER THROUGH TONIGHT AS A WARM FRONT PUSHES TOWARD THE COAST AND INLAND WITH MAIN FOCUS OF SCA ON SEAS REMAINING HIGH DUE TO ON SHORE PUSH. AS A WARM FRONT MOVES FARTHER INLAND THROUGH TONIGHT...WINDS WILL COME AROUND TO THE E TO SE. INCREASED CONVERGENCE/SHEAR ALONG THIS BOUNDARY WILL PRODUCE ISOLATED TSTMS. SMALL CRAFT ADVISORY CONDITIONS WILL PERSIST THROUGH THE NEAR TERM AND BEYOND. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 330 AM TUESDAY...WARM FRONT WILL BE NORTH OF THE WATERS TO START WEDNESDAY...AND GUSTY SOUTHERLY WINDS WILL BE ONGOING. WINDS OF 15-20 KTS WITH GUSTS UP TO 30 KTS WILL BE COMMON THROUGH WEDNESDAY...AND AN SCA WILL CARRYOVER FROM TUESDAY ACROSS ALL WATERS FOR 4-7 FT SEAS. AS THE WARM FRONT PROGRESSES FARTHER NORTH THROUGH WEDNESDAY...THE GRADIENT WILL RELAX...AND WINDS SPEEDS WILL EASE TO 10-15 KTS WEDNESDAY NIGHT WHILE ALSO SHIFTING MORE TO THE SW. THIS WILL BRING AN END TO THE ADVISORY AND WAVE HEIGHTS WILL BE 3-5 FT THURSDAY MORNING. W/SW WINDS OF 10-15 KTS WILL THEN PERSIST MUCH OF THURSDAY BEFORE A COLD FRONT DROPS SE ACROSS THE WATERS LATE...TURNING WINDS TO THE NW AT 10-15 KTS AND PUSHING THE HIGHEST SEAS EVEN FURTHER FROM SHORE LEAVING 2-4 FT WAVE HEIGHTS ACROSS THE COASTAL WATERS. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 330 AM TUESDAY...COLD FRONT WILL BE OFFSHORE TO START THE PERIOD AS HIGH PRESSURE BUILDS ACROSS THE REGION. WINDS INITIALLY WILL BE NW AROUND 15 KTS AS THE GRADIENT REMAINS PINCHED BEHIND THE FRONT...BUT WILL EASE AS THE HIGH MOVES OVERHEAD AND THEN OFFSHORE INTO SUNDAY. WIND SPEEDS WILL GENERALLY BE 10 KTS FRIDAY AFTN THROUGH THE END OF THE PERIOD...WITH DIRECTION VEERING FROM NW EARLY TO EAST LATE. SEAS OF 2-4 FT EARLY FRIDAY WILL DROP THROUGH THE PERIOD...BECOMING AROUND 2 FT SATURDAY. && .TIDES/COASTAL FLOODING... AS OF 200 PM TUESDAY...ALL RIVER AND WATER LEVELS HAVE DROPPED BELOW ADVISORY THRESHOLDS...BUT COASTAL FLOOD ADVISORIES WILL BE REQUIRED FOR SUCCESSIVE HIGH TIDES UP AND DOWN THE IMMEDIATE COAST AND FOR THE LOWER CAPE FEAR RIVER THROUGH MID WEEK DUE TO STRONG ONSHORE WINDS AND HIGH ASTRONOMICAL TIDES. THE FULL MOON IS TODAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR AMZ254-256. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT WEDNESDAY NIGHT FOR AMZ250-252. && $$ NEAR TERM...RGZ SHORT TERM...JDW/SRP LONG TERM...JDW AVIATION...DL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1220 PM CDT TUE OCT 27 2015 .UPDATE... ISSUED AT 1207 PM CDT TUE OCT 27 2015 LATEST RADARS SHOW A BAND OF SHOWERS MOVING THROUGH THE JAMES RIVER VALLEY AND SCATTERED SHOWERS NORTH CENTRAL. EARLIER LIGHTNING SEEMS TO HAVE ENDED EAST. COLD FRONT WILL MOVE THROUGH THIS AFTERNOON. CURRENT FORECAST LOOKS GOOD. UPDATE ISSUED AT 849 AM CDT TUE OCT 27 2015 A LOW PRESSURE AREA ACROSS WESTERN SOUTH DAKOTA AT 830 AM CDT HAS A WARM FRONTAL BOUNDARY EXTENDING NORTHEAST ACROSS SOUTHEAST NORTH DAKOTA. AREA OF RAIN ACROSS NORTH CENTRAL TRAILED OFF TO A NARROW BAND OF SHOWERS BETWEEN THE MISSOURI AND JAMES RIVER VALLEYS NORTH OF THE WARM FRONT. LOW LEVEL WARM AIR WILL MOVE NORTH INTO SOUTHEAST NORTH DAKOTA TODAY. CURRENT FORECAST LOOKS OK. MAY HAVE TO RAISE MAX TEMPS SOUTHEAST...BETWEEN WISHEK AND OAKES..IN THE WARM SECTOR OF THE SYSTEM. UPDATE ISSUED AT 637 AM CDT TUE OCT 27 2015 OVERALL...THE FORECAST REMAINS ON TRACK AS RAIN SHOWERS ACROSS CENTRAL NORTH DAKOTA CONTINUE TO PROPAGATE NORTH-NORTHEAST IN ASSOCIATION WITH AN UPPER LEVEL JET STREAK THIS MORNING. ONGOING FORECAST BLENDED TO OBSERVED TRENDS AND A TIME LAGGED ENSEMBLE OF THE 08-10 UTC HRRR ITERATIONS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 327 AM CDT TUE OCT 27 2015 CLOUDS AND CHANCES OF RAIN TODAY...TURNING COLDER TONIGHT WITH LIGHT RAIN OR FLURRIES POSSIBLE. CURRENTLY...AN UPPER LEVEL LOW PRESSURE SYSTEM EXTENDED FROM THE ROCKIES INTO THE WESTERN PLAINS...WITH EMBEDDED SHORTWAVES/LOWS WITHIN THE MAIN TROUGH CIRCULATING CYCLONICALLY THROUGH THE TROUGH. ONE OF THE CIRCULATION CENTERS WAS LOCATED OVER NORTHWESTERN NORTH DAKOTA/NORTHEASTERN MONTANA...WITH AN AREA OF LIGHT TO MODERATE RAIN EXTENDING FROM NORTHEASTERN MONTANA ACROSS NORTHERN NORTH DAKOTA. THIS AREA OF RAIN CONTINUED TO MOVE NORTHWARD. ANOTHER CIRCULATION CENTER WAS OVER SOUTH CENTRAL NORTH DAKOTA...AND ASSOCIATED WITH ANOTHER AREA OF RAIN FROM HETTINGER AND FORT YATES NORTHWARD TO MORTON AND BURLEIGH COUNTIES. AS THE CIRCULATION CENTERS LIFT NORTH/NORTHEASTWARD ACROSS THE REGION THE AREA OF RAIN SHOULD CONTINUE LIFTING NORTHWARD THROUGH THE MORNING HOURS. THUS THE RAIN SHOULD BE ENDING FROM SOUTH TO NORTH THROUGH THE MORNING HOURS. THEN THIS AFTERNOON THE UPPER LEVEL TROUGH AXIS ENTERS WESTERN NORTH DAKOTA AND ARRIVES IN CENTRAL NORTH DAKOTA BY EVENING. MEANWHILE AT THE SURFACE...A TROUGH OF LOW PRESSURE OVER THE FRONT RANGE EARLY THIS MORNING IS PROGGED TO MOVE EASTWARD IN ASSOCIATION WITH THE UPPER LEVEL TROUGH AXIS. BY THIS EVENING THE SURFACE TROUGH IS PROGGED TO BE IN THE DEVILS LAKE/JAMES RIVER BASINS. THIS WILL KEEP THE CHANCES OF RAIN IN THE FORECAST MAINLY OVER NORTHERN NORTH DAKOTA THIS AFTERNOON. WE WILL SEE YET ANOTHER - STRONGER - UPPER LEVEL SHORTWAVE DIVE SOUTHEAST OUT OF ALBERTA TODAY AND APPROACH NORTHWESTERN NORTH DAKOTA LATER THIS AFTERNOON AS THIS SHORTWAVE MERGES WITH THE AFOREMENTIONED UPPER LEVEL TROUGH. THIS WILL DEEPEN/INTENSIFY THE SYSTEM AS IT MOVES SOUTHEAST ACROSS NORTH DAKOTA TONIGHT AND WEDNESDAY. THIS WILL RESULT IN A BLAST OF COLDER AIR PUSHING INTO THE STATE BEHIND GUSTY NORTHWEST WINDS THAT ARE EXPECTED TO DEVELOP. AFTER TEMPERATURES IN THE UPPER 30S AND LOWER 40S THIS MORNING...AND HIGHS TODAY IN THE 45 TO 55 RANGE...THE COLD AIR INTRUSION SHOULD RESULT IN LOWS TUESDAY NIGHT FROM THE MID 20S IN THE WEST TO LOWER 30S IN THE JAMES RIVER VALLEY. CHANCES OF PRECIPITATION WILL REMAIN IN THE FORECAST TONIGHT...AND CHANCES OF RAIN WILL BECOME CHANCES OF SNOW FROM WEST TO EAST DURING THE EVENING HOURS. LIGHT PRECIP AMOUNTS WILL KEEP ANY SNOW FROM ACCUMULATING...EXCEPT PERHAPS SOME LIGHT ACCUMULATIONS IN THE TURTLE MOUNTAINS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 327 AM CDT TUE OCT 27 2015 A COOL AND WINDY WEDNESDAY HIGHLIGHTS THE EXTENDED FORECAST. GIVEN GOOD AGREEMENT AMONGST THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES...UTILIZED A BLEND FOR THE PERIOD. THE CURRENT SHORTWAVE ACROSS NORTHERN ALBERTA AND SASKATCHEWAN TUESDAY MORNING IS FORECAST TO PROPAGATE SOUTHEAST INTO THE EASTERN DAKOTAS WEDNESDAY MORNING AND DEEPEN. THE ASSOCIATED SURFACE COLD FRONT FROM THE SHORT TERM WILL ALREADY HAVE PROPAGATED THROUGH WESTERN AND CENTRAL NORTH DAKOTA...WITH A WINDY AND COOL POST FRONTAL DAY EXPECTED. 0.5 KM WINDS OF 35-40 KTS ARE FORECAST IN A TIGHT PRESSURE GRADIENT ON THE BACKSIDE OF CYCLOGENESIS ACROSS THE GREAT LAKES...SUPPORTING NEAR ADVISORY LEVEL GUSTS ACROSS MUCH OF THE AREA. HOWEVER...GIVEN THE MARGINAL VALUES...WILL NOT ISSUE ANY WIND HEADLINES AT THIS TIME. A FEW WRAP AROUND RAIN SHOWERS...POTENTIALLY MIXED WITH SNOW IN THE MORNING...ARE POSSIBLE EAST OF US HIGHWAY 83 WEDNESDAY. AFTER WEDNESDAY...A POTENTIAL WARM UP INTO THE 50S AND LOWER 60S IS FORECAST FOR THE WEEKEND AS THE UPPER LEVEL PATTERN IS EXPECTED TO SETTLE BACK TO NEAR ZONAL. HOWEVER...EARLY NEXT WEEK A LONGWAVE WESTERN CONUS TROUGH IS POSSIBLE...WHICH WOULD SIGNAL A POSSIBLE RETURN TO ACTIVE WEATHER ACROSS THE NORTHERN PLAINS MID TO LATE NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1207 PM CDT TUE OCT 27 2015 AT NOON CDT...A COLD FRONT EXTENDED ACROSS NORTHEAST MONTANA AND WILL MOVE EAST THIS AFTERNOON. MVFR CONDITIONS WILL PREVAIL ACROSS KISN-KDIK-KBIS-KMOT. VFR AT KJMS WILL BECOME MVFR AFTER 06Z. GUSTY NORTHWEST 20 TO 35 KTS WINDS ARE EXPECTED WEDNESDAY....WITH THE STRONGEST WINDS KJMS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...JV LONG TERM...AYD AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
909 AM CDT TUE OCT 27 2015 .UPDATE... ISSUED AT 849 AM CDT TUE OCT 27 2015 A LOW PRESSURE AREA ACROSS WESTERN SOUTH DAKOTA AT 830 AM CDT HAS A WARM FRONTAL BOUNDARY EXTENDING NORTHEAST ACROSS SOUTHEAST NORTH DAKOTA. AREA OF RAIN ACROSS NORTH CENTRAL TRAILED OFF TO A NARROW BAND OF SHOWERS BETWEEN THE MISSOURI AND JAMES RIVER VALLEYS NORTH OF THE WARM FRONT. LOW LEVEL WARM AIR WILL MOVE NORTH INTO SOUTHEAST NORTH DAKOTA TODAY. CURRENT FORECAST LOOKS OK. MAY HAVE TO RAISE MAX TEMPS SOUTHEAST...BETWEEN WISHEK AND OAKES..IN THE WARM SECTOR OF THE SYSTEM. UPDATE ISSUED AT 637 AM CDT TUE OCT 27 2015 OVERALL...THE FORECAST REMAINS ON TRACK AS RAIN SHOWERS ACROSS CENTRAL NORTH DAKOTA CONTINUE TO PROPAGATE NORTH-NORTHEAST IN ASSOCIATION WITH AN UPPER LEVEL JET STREAK THIS MORNING. ONGOING FORECAST BLENDED TO OBSERVED TRENDS AND A TIME LAGGED ENSEMBLE OF THE 08-10 UTC HRRR ITERATIONS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 327 AM CDT TUE OCT 27 2015 CLOUDS AND CHANCES OF RAIN TODAY...TURNING COLDER TONIGHT WITH LIGHT RAIN OR FLURRIES POSSIBLE. CURRENTLY...AN UPPER LEVEL LOW PRESSURE SYSTEM EXTENDED FROM THE ROCKIES INTO THE WESTERN PLAINS...WITH EMBEDDED SHORTWAVES/LOWS WITHIN THE MAIN TROUGH CIRCULATING CYCLONICALLY THROUGH THE TROUGH. ONE OF THE CIRCULATION CENTERS WAS LOCATED OVER NORTHWESTERN NORTH DAKOTA/NORTHEASTERN MONTANA...WITH AN AREA OF LIGHT TO MODERATE RAIN EXTENDING FROM NORTHEASTERN MONTANA ACROSS NORTHERN NORTH DAKOTA. THIS AREA OF RAIN CONTINUED TO MOVE NORTHWARD. ANOTHER CIRCULATION CENTER WAS OVER SOUTH CENTRAL NORTH DAKOTA...AND ASSOCIATED WITH ANOTHER AREA OF RAIN FROM HETTINGER AND FORT YATES NORTHWARD TO MORTON AND BURLEIGH COUNTIES. AS THE CIRCULATION CENTERS LIFT NORTH/NORTHEASTWARD ACROSS THE REGION THE AREA OF RAIN SHOULD CONTINUE LIFTING NORTHWARD THROUGH THE MORNING HOURS. THUS THE RAIN SHOULD BE ENDING FROM SOUTH TO NORTH THROUGH THE MORNING HOURS. THEN THIS AFTERNOON THE UPPER LEVEL TROUGH AXIS ENTERS WESTERN NORTH DAKOTA AND ARRIVES IN CENTRAL NORTH DAKOTA BY EVENING. MEANWHILE AT THE SURFACE...A TROUGH OF LOW PRESSURE OVER THE FRONT RANGE EARLY THIS MORNING IS PROGGED TO MOVE EASTWARD IN ASSOCIATION WITH THE UPPER LEVEL TROUGH AXIS. BY THIS EVENING THE SURFACE TROUGH IS PROGGED TO BE IN THE DEVILS LAKE/JAMES RIVER BASINS. THIS WILL KEEP THE CHANCES OF RAIN IN THE FORECAST MAINLY OVER NORTHERN NORTH DAKOTA THIS AFTERNOON. WE WILL SEE YET ANOTHER - STRONGER - UPPER LEVEL SHORTWAVE DIVE SOUTHEAST OUT OF ALBERTA TODAY AND APPROACH NORTHWESTERN NORTH DAKOTA LATER THIS AFTERNOON AS THIS SHORTWAVE MERGES WITH THE AFOREMENTIONED UPPER LEVEL TROUGH. THIS WILL DEEPEN/INTENSIFY THE SYSTEM AS IT MOVES SOUTHEAST ACROSS NORTH DAKOTA TONIGHT AND WEDNESDAY. THIS WILL RESULT IN A BLAST OF COLDER AIR PUSHING INTO THE STATE BEHIND GUSTY NORTHWEST WINDS THAT ARE EXPECTED TO DEVELOP. AFTER TEMPERATURES IN THE UPPER 30S AND LOWER 40S THIS MORNING...AND HIGHS TODAY IN THE 45 TO 55 RANGE...THE COLD AIR INTRUSION SHOULD RESULT IN LOWS TUESDAY NIGHT FROM THE MID 20S IN THE WEST TO LOWER 30S IN THE JAMES RIVER VALLEY. CHANCES OF PRECIPITATION WILL REMAIN IN THE FORECAST TONIGHT...AND CHANCES OF RAIN WILL BECOME CHANCES OF SNOW FROM WEST TO EAST DURING THE EVENING HOURS. LIGHT PRECIP AMOUNTS WILL KEEP ANY SNOW FROM ACCUMULATING...EXCEPT PERHAPS SOME LIGHT ACCUMULATIONS IN THE TURTLE MOUNTAINS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 327 AM CDT TUE OCT 27 2015 A COOL AND WINDY WEDNESDAY HIGHLIGHTS THE EXTENDED FORECAST. GIVEN GOOD AGREEMENT AMONGST THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES...UTILIZED A BLEND FOR THE PERIOD. THE CURRENT SHORTWAVE ACROSS NORTHERN ALBERTA AND SASKATCHEWAN TUESDAY MORNING IS FORECAST TO PROPAGATE SOUTHEAST INTO THE EASTERN DAKOTAS WEDNESDAY MORNING AND DEEPEN. THE ASSOCIATED SURFACE COLD FRONT FROM THE SHORT TERM WILL ALREADY HAVE PROPAGATED THROUGH WESTERN AND CENTRAL NORTH DAKOTA...WITH A WINDY AND COOL POST FRONTAL DAY EXPECTED. 0.5 KM WINDS OF 35-40 KTS ARE FORECAST IN A TIGHT PRESSURE GRADIENT ON THE BACKSIDE OF CYCLOGENESIS ACROSS THE GREAT LAKES...SUPPORTING NEAR ADVISORY LEVEL GUSTS ACROSS MUCH OF THE AREA. HOWEVER...GIVEN THE MARGINAL VALUES...WILL NOT ISSUE ANY WIND HEADLINES AT THIS TIME. A FEW WRAP AROUND RAIN SHOWERS...POTENTIALLY MIXED WITH SNOW IN THE MORNING...ARE POSSIBLE EAST OF US HIGHWAY 83 WEDNESDAY. AFTER WEDNESDAY...A POTENTIAL WARM UP INTO THE 50S AND LOWER 60S IS FORECAST FOR THE WEEKEND AS THE UPPER LEVEL PATTERN IS EXPECTED TO SETTLE BACK TO NEAR ZONAL. HOWEVER...EARLY NEXT WEEK A LONGWAVE WESTERN CONUS TROUGH IS POSSIBLE...WHICH WOULD SIGNAL A POSSIBLE RETURN TO ACTIVE WEATHER ACROSS THE NORTHERN PLAINS MID TO LATE NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 637 AM CDT TUE OCT 27 2015 WIDESPREAD IFR/LIFR CONDITIONS IN STRATUS/FOG/LIGHT RAIN ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING LIFTING TO MVFR/IFR THIS AFTERNOON. STRATUS REMAINING THROUGH THE NIGHT FOR MUCH OF THE AREA. KBIS/KJMS WILL HAVE A WINDOW THIS MORNING OF VFR CONDITIONS AS DRIER AIR BRIEFLY MOVES INTO THESE TERMINALS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...JV LONG TERM...AYD AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
642 AM CDT TUE OCT 27 2015 .UPDATE... ISSUED AT 637 AM CDT TUE OCT 27 2015 OVERALL...THE FORECAST REMAINS ON TRACK AS RAIN SHOWERS ACROSS CENTRAL NORTH DAKOTA CONTINUE TO PROPAGATE NORTH-NORTHEAST IN ASSOCIATION WITH AN UPPER LEVEL JET STREAK THIS MORNING. ONGOING FORECAST BLENDED TO OBSERVED TRENDS AND A TIME LAGGED ENSEMBLE OF THE 08-10 UTC HRRR ITERATIONS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 327 AM CDT TUE OCT 27 2015 CLOUDS AND CHANCES OF RAIN TODAY...TURNING COLDER TONIGHT WITH LIGHT RAIN OR FLURRIES POSSIBLE. CURRENTLY...AN UPPER LEVEL LOW PRESSURE SYSTEM EXTENDED FROM THE ROCKIES INTO THE WESTERN PLAINS...WITH EMBEDDED SHORTWAVES/LOWS WITHIN THE MAIN TROUGH CIRCULATING CYCLONICALLY THROUGH THE TROUGH. ONE OF THE CIRCULATION CENTERS WAS LOCATED OVER NORTHWESTERN NORTH DAKOTA/NORTHEASTERN MONTANA...WITH AN AREA OF LIGHT TO MODERATE RAIN EXTENDING FROM NORTHEASTERN MONTANA ACROSS NORTHERN NORTH DAKOTA. THIS AREA OF RAIN CONTINUED TO MOVE NORTHWARD. ANOTHER CIRCULATION CENTER WAS OVER SOUTH CENTRAL NORTH DAKOTA...AND ASSOCIATED WITH ANOTHER AREA OF RAIN FROM HETTINGER AND FORT YATES NORTHWARD TO MORTON AND BURLEIGH COUNTIES. AS THE CIRCULATION CENTERS LIFT NORTH/NORTHEASTWARD ACROSS THE REGION THE AREA OF RAIN SHOULD CONTINUE LIFTING NORTHWARD THROUGH THE MORNING HOURS. THUS THE RAIN SHOULD BE ENDING FROM SOUTH TO NORTH THROUGH THE MORNING HOURS. THEN THIS AFTERNOON THE UPPER LEVEL TROUGH AXIS ENTERS WESTERN NORTH DAKOTA AND ARRIVES IN CENTRAL NORTH DAKOTA BY EVENING. MEANWHILE AT THE SURFACE...A TROUGH OF LOW PRESSURE OVER THE FRONT RANGE EARLY THIS MORNING IS PROGGED TO MOVE EASTWARD IN ASSOCIATION WITH THE UPPER LEVEL TROUGH AXIS. BY THIS EVENING THE SURFACE TROUGH IS PROGGED TO BE IN THE DEVILS LAKE/JAMES RIVER BASINS. THIS WILL KEEP THE CHANCES OF RAIN IN THE FORECAST MAINLY OVER NORTHERN NORTH DAKOTA THIS AFTERNOON. WE WILL SEE YET ANOTHER - STRONGER - UPPER LEVEL SHORTWAVE DIVE SOUTHEAST OUT OF ALBERTA TODAY AND APPROACH NORTHWESTERN NORTH DAKOTA LATER THIS AFTERNOON AS THIS SHORTWAVE MERGES WITH THE AFOREMENTIONED UPPER LEVEL TROUGH. THIS WILL DEEPEN/INTENSIFY THE SYSTEM AS IT MOVES SOUTHEAST ACROSS NORTH DAKOTA TONIGHT AND WEDNESDAY. THIS WILL RESULT IN A BLAST OF COLDER AIR PUSHING INTO THE STATE BEHIND GUSTY NORTHWEST WINDS THAT ARE EXPECTED TO DEVELOP. AFTER TEMPERATURES IN THE UPPER 30S AND LOWER 40S THIS MORNING...AND HIGHS TODAY IN THE 45 TO 55 RANGE...THE COLD AIR INTRUSION SHOULD RESULT IN LOWS TUESDAY NIGHT FROM THE MID 20S IN THE WEST TO LOWER 30S IN THE JAMES RIVER VALLEY. CHANCES OF PRECIPITATION WILL REMAIN IN THE FORECAST TONIGHT...AND CHANCES OF RAIN WILL BECOME CHANCES OF SNOW FROM WEST TO EAST DURING THE EVENING HOURS. LIGHT PRECIP AMOUNTS WILL KEEP ANY SNOW FROM ACCUMULATING...EXCEPT PERHAPS SOME LIGHT ACCUMULATIONS IN THE TURTLE MOUNTAINS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 327 AM CDT TUE OCT 27 2015 A COOL AND WINDY WEDNESDAY HIGHLIGHTS THE EXTENDED FORECAST. GIVEN GOOD AGREEMENT AMONGST THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES...UTILIZED A BLEND FOR THE PERIOD. THE CURRENT SHORTWAVE ACROSS NORTHERN ALBERTA AND SASKATCHEWAN TUESDAY MORNING IS FORECAST TO PROPAGATE SOUTHEAST INTO THE EASTERN DAKOTAS WEDNESDAY MORNING AND DEEPEN. THE ASSOCIATED SURFACE COLD FRONT FROM THE SHORT TERM WILL ALREADY HAVE PROPAGATED THROUGH WESTERN AND CENTRAL NORTH DAKOTA...WITH A WINDY AND COOL POST FRONTAL DAY EXPECTED. 0.5 KM WINDS OF 35-40 KTS ARE FORECAST IN A TIGHT PRESSURE GRADIENT ON THE BACKSIDE OF CYCLOGENESIS ACROSS THE GREAT LAKES...SUPPORTING NEAR ADVISORY LEVEL GUSTS ACROSS MUCH OF THE AREA. HOWEVER...GIVEN THE MARGINAL VALUES...WILL NOT ISSUE ANY WIND HEADLINES AT THIS TIME. A FEW WRAP AROUND RAIN SHOWERS...POTENTIALLY MIXED WITH SNOW IN THE MORNING...ARE POSSIBLE EAST OF US HIGHWAY 83 WEDNESDAY. AFTER WEDNESDAY...A POTENTIAL WARM UP INTO THE 50S AND LOWER 60S IS FORECAST FOR THE WEEKEND AS THE UPPER LEVEL PATTERN IS EXPECTED TO SETTLE BACK TO NEAR ZONAL. HOWEVER...EARLY NEXT WEEK A LONGWAVE WESTERN CONUS TROUGH IS POSSIBLE...WHICH WOULD SIGNAL A POSSIBLE RETURN TO ACTIVE WEATHER ACROSS THE NORTHERN PLAINS MID TO LATE NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 637 AM CDT TUE OCT 27 2015 WIDESPREAD IFR/LIFR CONDITIONS IN STRATUS/FOG/LIGHT RAIN ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING LIFTING TO MVFR/IFR THIS AFTERNOON. STRATUS REMAINING THROUGH THE NIGHT FOR MUCH OF THE AREA. KBIS/KJMS WILL HAVE A WINDOW THIS MORNING OF VFR CONDITIONS AS DRIER AIR BRIEFLY MOVES INTO THESE TERMINALS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...JV LONG TERM...AYD AVIATION...AYD
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
931 PM EDT WED OCT 28 2015 .SYNOPSIS... LOW PRESSURE WILL LIFT NORTHEAST THROUGH THE GREAT LAKES REGION PROVIDING A CONTINUED CHANCE OF SHOWERS TONIGHT. A PAIR OF COLD FRONTS WILL MOVE THROUGH OVERNIGHT...USHERING IN DRIER AND COOLER CONDITIONS THOUGH THE END OF THE WEEK. THE NEXT CHANCE FOR RAIN WILL OCCUR ON SATURDAY WITH THE APPROACH OF ANOTHER COLD FRONT. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... THE MAIN FOCUS FOR THE EVENING FORECAST UPDATE WAS TO SHARPEN THINGS UP WITH REGARDS TO THE COLD FRONT NOW MOVING INTO INDIANA. THIS FRONT IS VERY WELL DEFINED ON MODEL THETA-E PLOTS...SURFACE WIND/T/TD OBSERVATIONS...AND REGIONAL MOSAIC RADAR. THIS FRONT IS FORECAST TO MOVE THROUGH THE ILN FORECAST AREA DURING THE 04Z TO 10Z TIME FRAME. POPS WERE INCREASED SIGNIFICANTLY IN A NARROW BAND ALONG THE FRONT...AS IT IS LIKELY THAT MOST SPOTS ON THE MAP WILL AT LEAST PICK UP A LITTLE BIT OF PRECIPITATION. IN ADDITION...WIND GUSTS ALONG AND JUST BEHIND THE FRONT APPEAR TO BE REACHING UP TO AROUND 30 KNOTS...AND THIS WAS INCLUDED IN THE GRIDS AS WELL. THE 00Z HRRR WAS USED AS GUIDANCE FOR TIMING...AS ITS INITIALIZATION MATCHES THE CURRENT FRONTAL POSITION VERY WELL. FEW OTHER CHANGES WERE MADE...WITH THE PREVIOUS FORECAST THINKING FOR TEMPERATURES (A SIGNIFICANT DROP THROUGH MORNING) AND CLOUDS (GRADUAL CLEARING BEHIND THE FRONT) APPEARING TO BE ON TRACK. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... MID/UPR LEVEL LOW OVER NRN LOWER MICHIGAN TO TRANSLATE INTO SE CANADA ON THURSDAY. CYCLONIC LOW LEVEL FLOW WILL PERSIST ACRS THE GREAT LAKES...WHILE SFC HIGH PRESSURE BEGINS TO NOSE INTO THE OHIO VALLEY THURSDAY AFTN. EXPECT MORE CLOUDS ACRS THE NORTH AND MORE SUN SOUTH. TEMPERATURES WILL BE AROUND 10 DEGREES BELOW NORMAL WITH HIGHS RANGING FROM NEAR 50 NW TO THE UPPER 50S SE. SFC HIGH PRESSURE TO BUILD EAST BECOMING CENTERED OVER THE OHIO VALLEY FRIDAY. EXPECT A GOOD AMOUNT OF CLOUDS TO PERSIST THURSDAY NIGHT...ESPECIALLY ACROSS THE NORTH. LOWS THURSDAY NIGHT EXPECTED TO RANGE FROM THE MID 30S SE TO NEAR 40 NW. HIGHS ON FRIDAY WILL MODERATE SOME BUT WILL STILL BE AROUND 5 DEGREES BELOW NORMAL. EXPECT HIGHS GENERALLY IN THE MID/UPR 50S. LOW CLOUDS TO CLEAR FRIDAY NIGHT BUT AT THE SAME TIME HIGH LEVEL CLOUDS WILL SPILL IN FROM THE WEST AND THICKEN OVERNIGHT. A SOUTHERLY FLOW WHICH WILL DEVELOP ON THE BACK SIDE OF RETREATING HIGH PRESSURE AND CLOUDS WILL KEEP OVERNIGHT LOWS SLIGHTLY MILDER. EXPECT FRIDAY NIGHTS LOWS TO RANGE FROM THE LOWER 40S WEST TO THE UPPER 30S EAST. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... COLD FRONT CONTAINING AMPLE MOISTURE WILL BE APPROACHING ON SATURDAY. THIS SYSTEM WILL BRING BREEZY CONDITIONS AND A GOOD CHANCE OF SHOWERS BY SATURDAY EVENING. NAM OFFERS A BIT SLOWER SOLUTION IN KEEPING SHOWERS TO THE WEST THROUGH SATURDAY. WENT CLOSER TO FASTER GFS AND ECMWF. SHOWERS WILL BE MOVING OUT AND HIGH PRESSURE IN ON SUNDAY. A TROUGH OF LOW PRESSURE MAY BRING SHOWERS TO SOUTHERN LOCATIONS ON MONDAY. HIGH PRESSURE BUILDING AT THE SURFACE AND ALOFT IS EXPECTED TO PROVIDE DRY WEATHER TUESDAY AND WEDNESDAY. AS THE FLOW IN THE UPPER ATMOSPHERE BACKS FROM NORTHWEST TO SOUTHWEST ACCOMPANIED BY RISING 500 MB HEIGHTS...TEMPERATURES ARE FORECAST TO EXHIBIT A WARMING TREND. EXPECT HIGHS ON SATURDAY IN THE NEAR NORMAL MID AND UPPER 50S...INCREASING TO THE LOWER 60S SUNDAY...THEN THE MID AND UPPER 60S MONDAY THROUGH WEDNESDAY. && .AVIATION /02Z THURSDAY THROUGH MONDAY/... A BROKEN LINE OF SHOWERS IS MOVING THROUGH THE REGION...BUT SHOULD CLEAR OUT OF THE COLUMBUS TAF SITES BY 01Z. AFTER THIS HAS PASSED...GENERALLY VFR CONDITIONS (WITH SLIGHTLY LIGHTER WINDS) CAN BE EXPECTED FOR THE NEXT FEW HOURS. A COLD FRONT IS THEN FORECAST TO MOVE QUICKLY THROUGH THE AREA BETWEEN 04Z AND 08Z. THIS FRONT WILL BRING ANOTHER CHANCE OF SHOWERS...SOME MVFR CEILINGS...AND BRIEF GUSTY WINDS TO 25-30 KNOTS. THE WIND DIRECTION (AROUND 250-270 DEGREES) WILL NOT CHANGE APPRECIABLY AS THIS FRONT PASSES. ONCE THE FRONT HAS CLEARED...THE CHANCE FOR RAIN WILL BE OVER...AND SKIES WILL BEGIN TO CLEAR. THIS WILL ALLOW FOR A VFR FORECAST THROUGH THE REST OF THE TAF PERIOD. THE BIGGEST CONCERN ON THURSDAY WILL BE WITH WIND...AS WESTERLY WINDS GUSTING TO 25-30 KNOTS WILL BE POSSIBLE FOR SEVERAL HOURS DURING THE DAY. THESE WINDS WILL DIMINISH ON THURSDAY NIGHT. SOME LOW VFR TO MVFR CEILINGS WILL BE POSSIBLE ON THURSDAY NIGHT. OUTLOOK...MVFR CEILINGS ARE POSSIBLE THURSDAY NIGHT INTO FRIDAY. MVFR CEILINGS AND VISIBILITIES ARE POSSIBLE SATURDAY NIGHT AND SUNDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...AR NEAR TERM...HATZOS SHORT TERM...AR LONG TERM...CONIGLIO AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
132 AM EDT TUE OCT 27 2015 .SYNOPSIS... UPPER LEVEL SYSTEM WITH REMNANTS OF PATRICIA BRINGS RAIN LATE TONIGHT AND TUESDAY INTO WEDNESDAY. COLD FRONT CROSSES LATE WEDNESDAY. HIGH PRESSURE CROSSES FRIDAY THROUGH SATURDAY. && .NEAR TERM /THROUGH TODAY/... 130AM UPDATE... RADAR ECHOES BECOMING MORE NUMEROUS...BUT PRECIPITATION ASSOCIATED WITH THE ECHOES IS STILL FALLING OUT OF 9KFT DECKS...SO STILL LIKELY ONLY SEEING VARY LIGHT RAIN OR SPRINKLES. PREVIOUS DISCUSSION... NO REAL SIGNIFICANT CHANGES NEEDED TO PREVIOUS FORECAST. TWEAKED POPS SOME TODAY TO REFLECT CURRENT TRENDS USING HRRR AND WRFARW. FOR TONIGHT INTO TUESDAY TRIED TO ENHANCE THE DOWNSLOPE PRECIP SHADOW SOME IN THE I79 CORRIDOR...GOING WITH POP/QPF MINIMUM THERE. ON THE OTHER HAND...INCREASED POPS ACROSS THE EASTERN SLOPES AND FAR WESTERN CWA TO AT OR NEAR 100 PERCENT BY TOMORROW AFTERNOON AS A DEFORMATION BAND SLIDES NORTH ACROSS THE CWA. THIS IS ASSOCIATED WITH THE SURFACE LOW CURRENTLY COMING ASHORE FROM THE GULF OF MEXICO. THIS LOW WILL GRADUALLY DRIFT NORTHWARD UP THE MISSISSIPPI RIVER VALLEY THROUGH THE PERIOD AS IT STARTS TO FEEL THE INFLUENCE OF A STRONG UPPER LEVEL LOW ENTERING CENTRAL CANADA. WINDS WILL PICK UP TOMORROW AS 850MB FLOW INCREASES OUT OF THE E/SE TUESDAY. && .SHORT TERM /TONIGHT THROUGH THURSDAY/... STOUT BAROCLINIC LEAF READILY EVIDENT ON STLT TODAY OVER SE 1/4 OF THE CONUS. ASSOCIATED WITH UPPER LEVEL LOW OVER THE LOWER MISSISSIPPI VALLEY...THE CONFLUENCE ZONE WHERE THE NRN AND SRN STREAM JETS MEET OVER THE MID ATLANTIC REGION SERVED TO ENHANCE THE EFFECT. THE UPPER LEVEL LOW OPENS UP AS IT LIFTS NEWD TONIGHT...AND BECOMES A RATHER FLAT WAVE BY THE TIME IT CROSSES THE CWA TUE NT...IN SW UPPER LEVEL FLOW AHEAD OF A LARGER UPPER LEVEL TROUGH FAST APPROACHING FROM THE W EVEN AS IT FORMS OUT OF SEVERAL SMALLER S/W TROUGHS. THE ORIGINAL SFC FEATURE BECOMES WASHED OUT BY THE TIME IT REACHES THE CWA TUE NT...BUT A TIGHT W TO E LOW LEVEL GRADIENT SPELLS A CLASSIC RAIN SHADOW EFFECT ON STRONG SE FLOW. WITH THIS...AND MOST OF THE FORCING OUTSIDE UPSLOPE GENERATED IN THE UPPER LEVELS...RAINFALL TUE NT INTO WED SHOULD BE MANAGEABLE...A SLOW SOAKER WITH UP TO A HALF AN INCH OVER SIX HOUR PERIOD IN THE ERN UPSLOPE AREA OF WV...AND SLIGHTLY LESS OVER THE WRN FRINGES...AND LESS THAN A QUARTER INCH OVER SIX HOURS IN THE SHADOW AREA IN BETWEEN. MOMENTUM TRANSFER ALGORITHMS DO NOT MIX MUCH OF THE 70KTS SHOWN AT H85 OFF THE NAM12 TO THE SFC. THE STRONG INVERSION CREATED BY COOL ATLANTIC AIR FLOWING IN ON THE BACK SIDE OF A STRONG SFC HIGH SLIDING OFF THE NEW ENGLAND COAST...BENEATH WARMER AIR FLOWING IN ON SW MID LEVEL FLOW...WILL KEEP STRONG WIND GUSTS LIMITED TO THE VERY HIGHEST RIDGES. A NRN STREAM UPPER LEVEL LOW THEN DIGS INTO THE UPPER TROUGH...AS THE FINAL PIECE OF THE PUZZLE THAT ESTABLISHES A L/W TROUGH OVER THE ERN CONUS COME THU. A SFC LOW DEEPENS RAPIDLY WED IN RESPONSE TO THE DIGGING UPPER LEVEL LOW...AND PULLS QUICKLY NEWD...REACHING JAMES BAY IN CENTRAL CANADA BY THU MORNING. THIS PULLS A STRONG SFC COLD FRONT THROUGH THE AREA LATE WED INTO WED NT...FOLLOWED BY STRONG COLD ADVECTION INTO THU. THIS RESULTS IN GOOD MIXING THROUGH WED NT AND THU...ONCE THE LOW LEVEL INVERSION IS TAKEN OUT ON WED. THIS ALSO DRIES OUT THE WEATHER...AND STRONGER WIND GUSTS ARE REALIZED ON THU. THU EVENING FINDS THE L/W ALREADY LIFTING OUT THROUGH THE NERN STATES. TEMPERATURES TAKE A NON DIURNAL ROLLER COASTER RIDE...STEADY OR SLOWLY RISING ON TUE NT...AND THEN NEARLY STEADY IN THE COLD ADVECTION DURING THE DAY ON THU AS H85 TEMPERATURES DROP ABOUT 5C. USED MOSTLY TO NAM BASED GUIDANCE. HIGHS ARE NEAR THE LOW END OF THE GUIDANCE ENVELOP ON WED AND THE HIGH END ON THU WITH BETTER MIXING AND INCREASING SUNSHINE. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... THE UPPER TROF LIFTS AS QUICKLY AS IT ARRIVED THURSDAY NIGHT...TO BE REPLACED BY BUILDING HEIGHTS. THIS IS ALL IN RESPONSE TO A BUILDING RIDGE OVER THE W ATLANTIC. WHILE THIS WILL ENSURE DRY WX THRU SATURDAY...THE END OF THE WEEKEND AND EARLY NEXT WEEK LOOKS UNSETTLED. THE CULPRIT BEING AN UPPER LOW EJECTING OUT OF THE SW CONUS AND INTERACTING WITH THE N STREAM. GLOBAL MODEL SOLUTIONS VARY WITH AXIS OF THE UPPER RIDGE WHICH WILL BE CRUCIAL IN DETERMINING JUST HOW WET WET GET. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... EXTENSIVE AREAS OF RAIN AND CLOUD COVER EXPECTED WITH A DEVELOPING LOW PRESSURE SYSTEM TAPPING INTO GULF MOISTURE OVER THE NEXT 30 HOURS. WILL SEE SOME EXPECTED DROPS IN FLIGHT CATEGORIES AS THE RAIN OVERSPREADS THE CENTRAL APPALACHIANS AND MIDDLE OHIO VALLEY. SOUTHEAST DOWNSLOPING FOR THE LOWLAND SITES WILL AID IN KEEPING CATEGORIES FROM DROPPING BELOW MVFR FOR BOTH CEILINGS AND VISIBILITIES. IN FACT...VFR WILL MAKE APPEARANCES HERE AND THERE. OVER THE MOUNTAINS IN THE SOUTHEAST MOIST UPSLOPE...WILL KEEP BKW MVFR DUE TO THE STRENGTH OF THE UPSLOPE FLOW. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE...MEDIUM. ALTERNATE SCENARIOS: TIMING OF SHOWERS MAY VARY. TIMING OF MVFR ARRIVAL MAY VARY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE TUE 10/27/15 UTC 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14 EDT 1HRLY 23 00 01 02 03 04 05 06 07 08 09 10 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H M M BKW CONSISTENCY H H H H H H M M M M M M EKN CONSISTENCY H H H H H M M M M M H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 06Z WEDNESDAY... INCREASING SOUTHEAST WIND TUESDAY NIGHT INTO WEDNESDAY WILL LIKELY LEAD TO IFR CIGS ALONG THE EASTERN SLOPES. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...TRM/JMV/MZ/30 NEAR TERM...MZ/26 SHORT TERM...TRM LONG TERM...30 AVIATION...26
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
849 PM CDT WED OCT 28 2015 .UPDATE... INCREASED CLOUD COVER TONIGHT AND THURSDAY. ALSO...TWEAKED DEWPOINTS TONIGHT. && .DISCUSSION... QUIET WEATHER CAN BE EXPECTED TONIGHT WITH ABUNDANT HIGH LEVEL CLOUD COVER. NOT SURE IF CIRRUS TONIGHT WILL BE THICK ENOUGH TO AFFECT FORECAST LOWS. FOR NOW...DID NOT ALTER LOWS. LATEST HRRR DEPICTED THAT OVERNIGHT LOWS MAY A BIT WARMER THAN CURRENTLY FORECAST. HOWEVER...LIGHT WINDS WILL ALLOW FOR SOME RADIATIONAL COOLING. PRODUCTS HAVE BEEN UPDATED. MBS && .PREV DISCUSSION... /ISSUED 656 PM CDT WED OCT 28 2015/ DISCUSSION... SEE AVIATION AVIATION... ALL TERMINALS WILL STAY UNDER VFR CONDITIONS THROUGH THE ENTIRE FORECAST PERIOD. SFC WINDS WILL STAY LIGHT THROUGH TONIGHT. BY 12Z, A WEAK SFC TROUGH WILL BEGIN ADVANCING ACROSS NORTHERN OKLAHOMA, SHIFTING THE WINDS NORTHEASTERLY AT ALL TERMINALS AS THE DAY PROGRESSES. PREV DISCUSSION... /ISSUED 256 PM CDT WED OCT 28 2015/ DISCUSSION... PRIMARY FORECAST CONCERN REMAINS FOCUSED ON WIDESPREAD MODERATE TO HEAVY RAINFALL FRIDAY INTO SATURDAY. THROUGH TONIGHT... GUSTY N/NW WINDS WILL RELAX THROUGH THE MID TO LATE AFTN AS SFC HIGH PRESSURE SLOWLY BUILDS IN FROM THE WEST. LIGHT WINDS WILL DEVELOP OVERNIGHT WITH LOWS DIPPING INTO THE LOW TO MID 40S ACROSS MUCH OF THE REGION. THURSDAY... AHEAD OF THE ADVANCING WRN TROUGH... WINDS WILL REMAIN LIGHT... WITH LL FLOW GRADUALLY SHIFTING OUT OF THE S/SE INTO THE EVENING. TEMPS WILL BE FALL LIKE... LOWER 60S TO LOWER 70S SPREAD N- S ACROSS THE REGION. THURSDAY NIGHT-FRIDAY MORNING... THE WRN TROUGH... CURRENTLY WELL DEPICTED ON WV PUSHING ASHORE OF NORCAL/OR/WA... WILL CONTINUE TO DIG TOWARD SOCAL/BAJA/WRN AZ... PICKING UP MOISTURE FROM THE PAC/GULF OF CA... AS WELL AS INCREASING SERLY LL FLOW WELL AHEAD ACROSS THE WEST TX PLAINS FROM THE GULF... ADDING TO THE MOISTURE PROFILE. RUN TO RUN CONSISTENCY BETWEEN THE GFS AND ECMWF HAS REMAINED RELATIVELY SUPERB OVER THE PAST COUPLE RUNS AND SUPPORTED BY GOOD CONSISTENCY BETWEEN THE LATEST GFS ENSEMBLE PERTURBATIONS... RESULTING IN INCREASING CONFIDENCE IN THE OVERALL FORECAST. AT PRESENT... PRECIP CHANCES LOOK TO INCREASE ACROSS W TX/TX PH/WRN OK AFTER MID/EARLY FRI AM. A STRONG SRLY LLJ WILL DEVELOP...30 TO 40KTS... INCREASING LL MOISTURE RETURN ACROSS THE SRN PLAINS. ISENTROPIC ANALYSIS AND BUFR SOUNDINGS REVEAL A WELL SATURATED ATMOSPHERE BY FRI MORNING ACROSS WRN OK/WRN N TX. FOR INITIAL PRECIP CHANCES... ONLY MADE A MENTION OF SLIGHT CHANCE OF THUNDER GIVEN INITIAL PRECIP WILL BE DRIVEN BY STOUT ISENTROPIC ASCENT OFF THE LLANO ESTACADO INTO WRN/CENTRAL OK... DEVOID OF STEEP LAPSE RATES AND LITTLE INSTABILITY. FRIDAY... RAIN CHANCES WILL INCREASE SIGNIFICANTLY ACROSS NRN TX INTO SRN OK THROUGH THE MORNING AS THE H500 LOW BEGINS TO LIFT E/NE ACROSS NM AND THE UPPER RIO GRAND VALLEY WHILE THE ASSOCIATED SFC LOW BEGINS TO SHIFT EASTWARD ACROSS THE W TX PLAINS. THE LATEST GFS AND ECMWF REMAIN CONSISTENT IN A RELATIVELY NARROW CORRIDOR OF HIGHER RAINFALL AMOUNTS DEVELOPING FROM WRN N TX INTO SRN AND CENTRAL OK. THIS SOLUTION APPEARS TO BE DRIVEN BY THE SURGE OF THE H850 FRONT AND ASSOCIATED SFC TROUGH RESULTING IN STRONG ISENTROPIC ASCENT PAIRED WITH INCREASING ELEVATED INSTABILITY AND SHEAR. WITH AN INCREASING SIGNAL FOR SOME EMBEDDED CONVECTIVE DEVELOPMENT AND/OR BANDING... AGREE WITH THE LATEST WPC QPF (RAINFALL) FORECAST... INCREASING AMOUNTS DURING THE DAYTIME HOURS INTO THE EVENING. AT PRESENT TIME... THE HEAVIEST AMOUNTS WILL LIKELY OCCUR ALONG AND BETWEEN THE I-44 AND I-35 CORRIDORS FRIDAY... BETWEEN 2 TO 3 INCHES OF WIDESPREAD RAIN ACCUMULATING BETWEEN FRIDAY AND FRIDAY NIGHT. LATE EVENING/OVERNIGHT... GREATER RAINFALL CHANCES WILL SHIFT EAST... PRIMARILY ALONG/EAST OF THE I-35 CORRIDOR AS THE UPPER TROUGH PUSHES INTO WEST TEXAS. IN RESPONSE... THE GREATEST RAINFALL AMOUNTS WILL SHIFT E/SE ACROSS SOUTH CENTRAL OK THROUGH MIDNIGHT... WITH ANYWHERE FROM 1.5 TO 2 INCHES ACCUMULATING EAST OF I-35 AND SOUTH OF I-40. SATURDAY... RAIN CHANCES WILL CONTINUE SLIDE EASTWARD... WITH SCATTERED SHOWERS LINGERING ACROSS CENTRAL AND WRN OK/WRN N TX THROUGH THE MORNING. THROUGH THE DAY... THE H500 TROUGH WILL CONTINUE TO LIFT E/NE ACROSS THE SRN PLAINS... WITH PRECIP CHANCES DROPPING OFF QUICKLY INTO THE AFTN/EVENING. THIS IS GOOD NEWS FOR TRICK OR TREATERS AND THOSE COMING OUT TO THE WEATHER FESTIVAL AT THE NATIONAL WEATHER CENTER (I HIGHLY SUGGEST YOU VISIT THE NWC). IT IS LOOKING MORE LIKELY THE AFTN AND EVENING WILL BE DRY... BUT SOME ISOLATED SHOWERS MAY LOITER ACROSS THE AREA... WITH THE BEST CHANCE ACROSS SOUTH CENTRAL OK. OVERALL... PRECIP AMOUNTS ACROSS THE AREA WILL RANGE FROM NEAR AN INCH TO UP TO 3 INCHES. THE HIGHEST AMOUNTS... 2 TO 3 INCHES... REMAIN MOST LIKELY ACROSS SOUTHERN INTO CENTRAL OK INTO NRN TX... ALONG/BETWEEN THE I-44 AND I-35 CORRIDORS AND INTO SOUTH CENTRAL OK. WITH THIS FORECAST... WILL HOLD OFF ON A FLASH FLOOD WATCH DUE TO THE LONG DURATION AND THE AMOUNTS EXPECTED. HOWEVER... AS ALWAYS... WE WILL KEEP A CLOSE EYE AS THIS SYSTEM EVOLVES. FOR SUNDAY... WILL KEEP LOW PRECIP CHANCES GOING ACROSS FAR SOUTH CENTRAL OK INTO SUNDAY... BUT THE VAST MAJORITY WILL REMAIN DRY AS HIGH PRESSURE BUILDS OVER THE AREA. A WARM UP CAN BE EXPECTED AT THE START OF NEXT WEEK AS S/SW FLOW INCREASES AHEAD OF ANOTHER ADVANCING WRN TROUGH. HIGHS ON MONDAY WILL REACH THE MID TO UPPER 70S... CONTINUING INTO TUESDAY. LONG RANGE GUIDANCE IS ALSO HINTING AT RETURNING PRECIP CHANCES BY THE MIDDLE OF NEXT WEEK. JTK && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 43 65 47 61 / 0 0 30 90 HOBART OK 45 67 50 59 / 0 0 40 90 WICHITA FALLS TX 48 75 53 67 / 0 0 60 100 GAGE OK 38 61 44 55 / 0 0 30 70 PONCA CITY OK 38 62 42 58 / 0 0 10 90 DURANT OK 49 73 52 68 / 0 0 20 90 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 17/68
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1019 PM EDT WED OCT 28 2015 .SYNOPSIS... A COLD FRONT WILL SWING ACROSS THE REGION OVERNIGHT AND EARLY THURSDAY...FOLLOWED BY DRIER CONDITIONS. A SEASONABLY COLDER LAKE EFFECT SHOWER/NORTHWEST FLOW PATTERN WILL END THE WEEK. THE TEMPERATURES SHOULD REBOUND NICELY OVER THE WEEKEND WITH FAIR WEATHER. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... RADAR SHOWS LOCALLY HEAVY RAIN WITH EMBEDDED THUNDER WORKING ACROSS CENTRAL AREAS AS OF 10 PM. ANOTHER MESO LOW/STRONG ROTATING THUNDERSTORM IS TRACKING NORTH THROUGH THE LOWER SUSQ VALLEY WHERE SEVERAL REPORTS OF WIND DAMAGE HAVE BEEN REPORTED. MESO ANAL HAS THE COLD FRONT APPROACHING THE OHIO/PA BORDER...WITH A LEE SIDE TROUGH FEATURE FORMING FURTHER EAST OVER THE SUSQ VALLEY. HRRR STILL SHOWS THE LARGEST MOST ORGANIZED AREA OF RAIN MOVING THROUGH BY AROUND MIDNIGHT OR INTO THE WEE HOURS...WITH JUST SCATTERED SHOWERS REMAINING FOR THE REMAINDER OF THE OVERNIGHT. COLD/OCCLUDED FRONT WILL MOVE THROUGH BY MORNING BUT THE REAL PUSH OF THE COOLER AIR WILL NOT BE IMMEDIATELY BEHIND THE FRONT...WITH THURSDAY STILL ENDING UP RELATIVELY MILD. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... NOT MUCH RISE IS SEEN IN TEMPS ON THURSDAY. BUT SOME SUN SHOULD BREAK THROUGH POST-FRONT. WRAP AROUND/LAKE EFFECT MOISTURE WILL START TO CLOSE BACK IN ON THE NW THURS EVENING. WINDS MAY BE GUSTIER IN MANY LOCATIONS THURSDAY COMPARED TO TODAY AS THE DRY AIR MOVES IN AND DEEP VERTICAL MIXING TO 5-7 KFT AGL TAPS WESTERLY WINDS OF 50 KTS AT THE TOP OF THE LAYER. MEAN GUSTS WILL LIKELY BE IN THE 30-35 KTS RANGE...BUT A FEW COULD TICKLE THE 40 KT RANGE ACRS THE HIGHER TERRAIN. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... A BROAD CYCLONIC FLOW PATTERN ASSOCIATED WITH THE DEPARTING UPPER LEVEL TROUGH OVER SOUTHEASTERN CANADA WILL TRANSITION TOWARD A MILDER SOUTHWEST FLOW ALOFT THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THE EXACT TIMING/STRENGTH OF A SERIES OF SHORTWAVE EJECTIONS FROM THE SOUTHERN PLAINS IS YET-TO-BE DETERMINED AND WILL CONTINUE TO RESULT IN A LOWER CONFIDENCE FCST WITH RESPECT TO THE PCPN PATTERN OVER THE REGION. HOWEVER...THE 28/12Z MODEL AND ENSEMBLE GUIDANCE REMAIN VERY CONSISTENT IN BUILDING AN ANOMALOUS UPPER LEVEL RIDGE OVER THE EASTERN U.S. BY NEXT TUE-WED WHICH WILL ALMOST CERTAINLY SUPPORT MAX/MIN TEMPERATURES WELL ABOVE CLIMO INTO EARLY NOVEMBER. A SHOT OF MODESTLY COLDER AIR IN THE NW FLOW ALOFT WILL FOLLOW A SECONDARY FROPA AND BRING LAKE EFFECT/HIGHER ELEVATION SHOWERS TO THE NW ALLEGHENIES LATE THURSDAY NIGHT INTO EARLY FRIDAY MORNING. TEMPS STILL LOOK MARGINAL FOR SNOW BUT WILL KEEP MENTION OF RAIN/SNOW SHOWERS IN THE FCST. AS MENTIONED...CONFIDENCE IS LOW REGARDING OVERALL RAIN RISK AND TIMING/PLACEMENT/EXTENT LATER THIS WEEKEND AND INTO EARLY NEXT WEEK. DRY WX SHOULD PREVAIL DURING THE DAY ON SATURDAY. THE OP ECMWF AND GFS WANT TO DEVELOP A SRN STREAM LOW EARLY NEXT WEEK WITH A CONSENSUS APPROACH PLACING THE HIGHEST POPS ALONG AND SOUTH OF THE MASON DIXON LINE. && .AVIATION /02Z THURSDAY THROUGH MONDAY/... A DEEP STORM WILL TRACK NORTHWARD ACROSS THE UPPER GREAT LAKES LATE TODAY. IT/S SOUTHWARD TRAILING COLD FRONT /AND WARM FRONT/ WILL BRING GUSTY SE TO SOUTH WINDS...PERIODS OF MDT TO HEAVY RAIN...AND WIDESPREAD MVFR TO IFR CONDITIONS ACROSS THE AREA THROUGH AT LEAST THIS FIRST HALF OF TONIGHT. WILL CONTINUE TO HIGHLIGHT LLWS AHEAD OF THE APPROACHING COLD/OCCLUDED FRONT THROUGH EARLY TONIGHT. THERE IS SOME RISK FOR STRONG TO EVEN SEVERE THUNDERSTORMS LATE TODAY...AND MORE LIKELY THIS EVENING...GIVEN INCREASE IN DEWPOINTS AND VERY STRONG LLVL WIND FIELDS IN CLOSE PROXIMITY TO THE NWD ADVANCING WARM FRONT. THE STEADY RAIN WILL TAPER OFF FROM WEST TO EAST TONIGHT...AS A STRONG COLD FRONT MOVES ACROSS THE AREA. A DRY SLOT SHOULD HELP CLEAR IT OUT EARLY THU...BUT SOME SHOWERS AND LOWER CIGS WILL BE POSSIBLE ACROSS THE MOUNTAINS. GUSTY WEST TO WSW WIND AOA 30 KTS EXPECTED AT ALL TAF SITES AFTER 15Z WEDNESDAY AS COLDER AIR MOVES IN ALOFT AND COMBINES WITH LIMITED SFC HEATING THROUGH THE BKN STRATO CU DECK. OUTLOOK... THU...WINDY. AM SHOWERS/LOW CIGS POSSIBLE...MAINLY NW. FRI-SUN...NO SIG WX EXPECTED. && .HYDROLOGY... RAINFALL AMOUNTS THROUGH THIS AFTERNOON HAVE GENERALLY RANGED BETWEEN 1 AND 2 INCHES. MINOR FLOODING DUE TO CLOGGED STORM DRAINS...PONDING/STANDING WATER WILL LIKELY CONTINUE INTO TONIGHT. MINOR RISES ARE FORECAST ON AREA RIVERS..STREAMS AND CREEKS BUT NO FLOODING IS EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LAMBERT LONG TERM...STEINBUGL AVIATION...CERU/MARTIN HYDROLOGY...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
817 PM EDT WED OCT 28 2015 .SYNOPSIS... A COLD FRONT WILL SWING ACROSS THE REGION OVERNIGHT AND EARLY THURSDAY...FOLLOWED BY DRIER CONDITIONS. A SEASONABLY COLDER LAKE EFFECT SHOWER/NORTHWEST FLOW PATTERN WILL END THE WEEK. THE TEMPERATURES SHOULD REBOUND NICELY OVER THE WEEKEND WITH FAIR WEATHER. && .NEAR TERM /UNTIL MIDNIGHT TONIGHT/... RADAR CONTINUES TO SHOW MODERATE TO HEAVY RAIN TRACKING NORTH THROUGH MY EASTERN ZONES...WITH MORE DISORGANIZED BANDS OF RAIN AFFECTING CENTRAL AND WESTERN LOCATIONS. THE EASTERN RAINS ARE ON THE NOSE OF A LOW LEVEL JET CORE SURGING UP ALONG THE COASTAL PLAIN. THE WESTERN RAINS SEEM MORE ASSOCIATED WITH AN AREA OF LOW LEVEL CONFLUENCE AND MARKS THE EASTERN EXTENT OF SOME UNSTABLE AIR...WITH EVEN A FEW LIGHTNING STRIKES SHOWING UP FROM TIME TO TIME. THE LARGER PICTURE SHOWS THE COLD FRONT ENTERING EASTERN OHIO...WITH A HARD TO FIND/DIFFUSE EAST-WEST WARM FRONT BISECTING OUR FCST AREA. HRRR SHOWS BANDS OF RAIN CONTINUING THROUGH ABOUT MIDNIGHT BEFORE BECOMING MORE SHOWERY IN NATURE AS THE COLD FRONT MOVES INTO THE REGION. && .SHORT TERM /MIDNIGHT THROUGH 6 PM THURSDAY/... COLD/OCCLUDED FRONT MOVES THROUGH OVERNIGHT BUT THE REAL PUSH OF THE NEW AIRMASS DOES NOT COME UNTIL THURSDAY MORNING. THUS...THE TEMPS COULD REMAIN MILD ALL NIGHT WITH PLENTY OF CLOUD COVER AROUND AND JUST A 30-40 DEG WIND SHIFT BEHIND THE INITIAL CONVECTIVE LINE. THE LOWS WILL BE CLOSE TO NORMAL MAXES FOR THIS TIME OF YEAR...ABOUT 15 TO 20F ABOVE NORMALS. NOT MUCH RISE IS SEEN IN TEMPS ON THURSDAY. BUT SOME SUN SHOULD BREAK THROUGH POST-FRONT. WRAP AROUND/LAKE EFFECT MOISTURE WILL START TO CLOSE BACK IN ON THE NW THURS EVENING. WINDS MAY BE GUSTIER IN MANY LOCATIONS THURSDAY COMPARED TO TODAY AS THE DRY AIR MOVES IN AND DEEP VERTICAL MIXING TO 5-7 KFT AGL TAPS WESTERLY WINDS OF 50 KTS AT THE TOP OF THE LAYER. MEAN GUSTS WILL LIKELY BE IN THE 30-35 KTS RANGE...BUT A FEW COULD TICKLE THE 40 KT RANGE ACRS THE HIGHER TERRAIN. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... A BROAD CYCLONIC FLOW PATTERN ASSOCIATED WITH THE DEPARTING UPPER LEVEL TROUGH OVER SOUTHEASTERN CANADA WILL TRANSITION TOWARD A MILDER SOUTHWEST FLOW ALOFT THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THE EXACT TIMING/STRENGTH OF A SERIES OF SHORTWAVE EJECTIONS FROM THE SOUTHERN PLAINS IS YET-TO-BE DETERMINED AND WILL CONTINUE TO RESULT IN A LOWER CONFIDENCE FCST WITH RESPECT TO THE PCPN PATTERN OVER THE REGION. HOWEVER...THE 28/12Z MODEL AND ENSEMBLE GUIDANCE REMAIN VERY CONSISTENT IN BUILDING AN ANOMALOUS UPPER LEVEL RIDGE OVER THE EASTERN U.S. BY NEXT TUE-WED WHICH WILL ALMOST CERTAINLY SUPPORT MAX/MIN TEMPERATURES WELL ABOVE CLIMO INTO EARLY NOVEMBER. A SHOT OF MODESTLY COLDER AIR IN THE NW FLOW ALOFT WILL FOLLOW A SECONDARY FROPA AND BRING LAKE EFFECT/HIGHER ELEVATION SHOWERS TO THE NW ALLEGHENIES LATE THURSDAY NIGHT INTO EARLY FRIDAY MORNING. TEMPS STILL LOOK MARGINAL FOR SNOW BUT WILL KEEP MENTION OF RAIN/SNOW SHOWERS IN THE FCST. AS MENTIONED...CONFIDENCE IS LOW REGARDING OVERALL RAIN RISK AND TIMING/PLACEMENT/EXTENT LATER THIS WEEKEND AND INTO EARLY NEXT WEEK. DRY WX SHOULD PREVAIL DURING THE DAY ON SATURDAY. THE OP ECMWF AND GFS WANT TO DEVELOP A SRN STREAM LOW EARLY NEXT WEEK WITH A CONSENSUS APPROACH PLACING THE HIGHEST POPS ALONG AND SOUTH OF THE MASON DIXON LINE. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... A DEEP STORM WILL TRACK NORTHWARD ACROSS THE UPPER GREAT LAKES LATE TODAY. IT/S SOUTHWARD TRAILING COLD FRONT /AND WARM FRONT/ WILL BRING GUSTY SE TO SOUTH WINDS...PERIODS OF MDT TO HEAVY RAIN...AND WIDESPREAD MVFR TO IFR CONDITIONS ACROSS THE AREA THROUGH AT LEAST THIS FIRST HALF OF TONIGHT. WILL CONTINUE TO HIGHLIGHT LLWS AHEAD OF THE APPROACHING COLD/OCCLUDED FRONT THROUGH EARLY TONIGHT. THERE IS SOME RISK FOR STRONG TO EVEN SEVERE THUNDERSTORMS LATE TODAY...AND MORE LIKELY THIS EVENING...GIVEN INCREASE IN DEWPOINTS AND VERY STRONG LLVL WIND FIELDS IN CLOSE PROXIMITY TO THE NWD ADVANCING WARM FRONT. THE STEADY RAIN WILL TAPER OFF FROM WEST TO EAST TONIGHT...AS A STRONG COLD FRONT MOVES ACROSS THE AREA. A DRY SLOT SHOULD HELP CLEAR IT OUT EARLY THU...BUT SOME SHOWERS AND LOWER CIGS WILL BE POSSIBLE ACROSS THE MOUNTAINS. GUSTY WEST TO WSW WIND AOA 30 KTS EXPECTED AT ALL TAF SITES AFTER 15Z WEDNESDAY AS COLDER AIR MOVES IN ALOFT AND COMBINES WITH LIMITED SFC HEATING THROUGH THE BKN STRATO CU DECK. OUTLOOK... THU...WINDY. AM SHOWERS/LOW CIGS POSSIBLE...MAINLY NW. FRI-SUN...NO SIG WX EXPECTED. && .HYDROLOGY... RAINFALL AMOUNTS THROUGH THIS AFTERNOON HAVE GENERALLY RANGED BETWEEN 1 AND 2 INCHES. MINOR FLOODING DUE TO CLOGGED STORM DRAINS...PONDING/STANDING WATER WILL LIKELY CONTINUE INTO TONIGHT. MINOR RISES ARE FORECAST ON AREA RIVERS..STREAMS AND CREEKS BUT NO FLOODING IS EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LA CORTE/LAMBERT SHORT TERM...LAMBERT LONG TERM...STEINBUGL AVIATION...CERU/MARTIN HYDROLOGY...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
758 PM EDT WED OCT 28 2015 .SYNOPSIS... A POWERFUL STORM THAT HAS COMBINED WITH THE REMNANTS OF WHAT WAS ONCE HURRICANE PATRICIA IN THE EASTERN PACIFIC...WILL MOVE ACROSS THE UPPER GREAT LAKES REGION LATE TODAY AND TONIGHT...CONTINUING TO BRING RAIN AND GUSTY WINDS TO OUR REGION THROUGH THE FIRST HALF OF TONIGHT. THE SOUTHWARD TRAILING COLD FRONT WILL PUSH THROUGH PENNSYLVANIA THURSDAY MORNING. A SEASONABLY COLDER LAKE EFFECT SHOWER/NORTHWEST FLOW PATTERN WILL END THE WEEK. THE TEMPERATURES SHOULD REBOUND NICELY OVER THE WEEKEND WITH FAIR WEATHER. && .NEAR TERM /UNTIL MIDNIGHT TONIGHT/... A FEW BANDS OF MDT TO HVY RAIN WILL CONTINUE TO LIFT QUICKLY NE ACROSS THE FCST AREA LATER THIS AFTERNOON AND THIS EVENING AS THE AXIS OF A POTENT /3-4 SIGMA/ SSE LLJ SLIDES EAST ACRS THE REGION AND A WARM FRONT LIFTS NORTH TWD THE MASON/DIXON LINE. SPC MESOANALYSIS AND 17Z HRRR INDICATE THAT ALTHOUGH SFC BASED CAPE IS NON-EXISTENT NOW...INSTABILITY WILL INCREASE AND YIELD A FEW TO SVRL HUNDRED J/KG OF CAPE LATE THIS AFTERNOON THROUGH EARLY TONIGHT AHEAD OF THE ONE-TWO PUNCH OF THE NEWD ADVANCING WARM FRONT...AND EWD MOVING SFC COLD/OCCLUDED FRONT FROM THE OHIO VALLEY. BLENDED SREF AND HRRR QPF YIELDS ANOTHER 1-1.5 INCHES ACROSS THE REGION WITH LOCALLY HIGHER AMTS ACROSS EASTERN PARTS OF THE CWA. SREF PROB OF CAPE GREATER THAN 500 J/KG PEAKS AT AROUND 50 PERCENT SHORTLY AFTER MIDNIGHT TONIGHT ACROSS THE LOWER SUSQ VALLEY...WITH THE NEARLY NORTH-SOUTH RIBBON OF INSTABILITY MOVING THROUGH THE CENTRAL ZONES 00-03Z. SPC MARGINAL RISK FOR SEVERE TSRA LOOKS GOOD BASED ON THESE CONVECTIVE/KINEMATIC PARAMETERS...WITH THE PRIMARY SEVERE WEATHER THREAT BEING A NARROW COLD FRONTAL RAIN BAND WITH LOW-TOPPED TSRA AND BRIEFLY STRONG SWRLY WIND GUSTS OF 40-50 KTS. THERE`S EVEN A LOW PROBABILITY FOR A TORNADO OR TWO NEAR THE WARM FRONT...WHERE LLVL SHEAR WILL BE THE STRONGEST AND LCLS WELL BELOW 1000M AGL. && .SHORT TERM /MIDNIGHT THROUGH 6 PM THURSDAY/... COLD/OCCLUDED FRONT MOVES THROUGH OVERNIGHT BUT THE REAL PUSH OF THE NEW AIRMASS DOES NOT COME UNTIL THURSDAY MORNING. THUS...THE TEMPS COULD REMAIN MILD ALL NIGHT WITH PLENTY OF CLOUD COVER AROUND AND JUST A 30-40 DEG WIND SHIFT BEHIND THE INITIAL CONVECTIVE LINE. THE LOWS WILL BE CLOSE TO NORMAL MAXES FOR THIS TIME OF YEAR...ABOUT 15 TO 20F ABOVE NORMALS. NOT MUCH RISE IS SEEN IN TEMPS ON THURSDAY. BUT SOME SUN SHOULD BREAK THROUGH POST-FRONT. WRAP AROUND/LAKE EFFECT MOISTURE WILL START TO CLOSE BACK IN ON THE NW THURS EVENING. WINDS MAY BE GUSTIER IN MANY LOCATIONS THURSDAY COMPARED TO TODAY AS THE DRY AIR MOVES IN AND DEEP VERTICAL MIXING TO 5-7 KFT AGL TAPS WESTERLY WINDS OF 50 KTS AT THE TOP OF THE LAYER. MEAN GUSTS WILL LIKELY BE IN THE 30-35 KTS RANGE...BUT A FEW COULD TICKLE THE 40 KT RANGE ACRS THE HIGHER TERRAIN. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... A BROAD CYCLONIC FLOW PATTERN ASSOCIATED WITH THE DEPARTING UPPER LEVEL TROUGH OVER SOUTHEASTERN CANADA WILL TRANSITION TOWARD A MILDER SOUTHWEST FLOW ALOFT THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THE EXACT TIMING/STRENGTH OF A SERIES OF SHORTWAVE EJECTIONS FROM THE SOUTHERN PLAINS IS YET-TO-BE DETERMINED AND WILL CONTINUE TO RESULT IN A LOWER CONFIDENCE FCST WITH RESPECT TO THE PCPN PATTERN OVER THE REGION. HOWEVER...THE 28/12Z MODEL AND ENSEMBLE GUIDANCE REMAIN VERY CONSISTENT IN BUILDING AN ANOMALOUS UPPER LEVEL RIDGE OVER THE EASTERN U.S. BY NEXT TUE-WED WHICH WILL ALMOST CERTAINLY SUPPORT MAX/MIN TEMPERATURES WELL ABOVE CLIMO INTO EARLY NOVEMBER. A SHOT OF MODESTLY COLDER AIR IN THE NW FLOW ALOFT WILL FOLLOW A SECONDARY FROPA AND BRING LAKE EFFECT/HIGHER ELEVATION SHOWERS TO THE NW ALLEGHENIES LATE THURSDAY NIGHT INTO EARLY FRIDAY MORNING. TEMPS STILL LOOK MARGINAL FOR SNOW BUT WILL KEEP MENTION OF RAIN/SNOW SHOWERS IN THE FCST. AS MENTIONED...CONFIDENCE IS LOW REGARDING OVERALL RAIN RISK AND TIMING/PLACEMENT/EXTENT LATER THIS WEEKEND AND INTO EARLY NEXT WEEK. DRY WX SHOULD PREVAIL DURING THE DAY ON SATURDAY. THE OP ECMWF AND GFS WANT TO DEVELOP A SRN STREAM LOW EARLY NEXT WEEK WITH A CONSENSUS APPROACH PLACING THE HIGHEST POPS ALONG AND SOUTH OF THE MASON DIXON LINE. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... AS THE WARM FRONT CONTINUES TO MOVE TO THE NORTH PERIODS OF MDT TO HEAVY RAIN WILL CONTINUE. EXPECT WIDESPREAD MVFR TO IFR CONDITIONS ACROSS THE AREA THROUGH AT LEAST THIS FIRST HALF OF TONIGHT. WILL CONTINUE TO HIGHLIGHT LLWS AHEAD OF THE APPROACHING COLD/OCCLUDED FRONT THROUGH EARLY TONIGHT. THE LLWS SHOULD BEGIN TO WEAKEN AND LIFT AS THE WINDS SHIFT TO A MORE WESTERLY DIRECTION WHICH SHOULD OCCUR BETWEEN 03Z TO 09Z. SOME TSRA IS OCCURRING AT MDT...WITH IFR CIGS AND VSBYS. CONVECTION REMAINS LIKELY UNTIL AROUND 03Z AT MDT AND POSSIBLY LNS. THERE REMAINS SOME RISK FOR STRONG TO EVEN SEVERE THUNDERSTORMS...GIVEN INCREASE IN DEWPOINTS AND VERY STRONG LLVL WIND FIELDS IN CLOSE PROXIMITY TO THE NWD ADVANCING WARM FRONT. AS THE FRONT LIFTS NORTHWARD AND THE LLWS SUBSIDES...THE THREAT OF STORMS WILL DIMINISH. THE STEADY RAIN WILL TAPER OFF FROM WEST TO EAST TONIGHT...AS A STRONG COLD FRONT MOVES ACROSS THE AREA. A DRY SLOT SHOULD HELP CLEAR IT OUT EARLY THU...BUT SOME SHOWERS AND LOWER CIGS WILL BE POSSIBLE ACROSS THE MOUNTAINS INTO MID THURSDAY. GUSTY WEST TO WSW WIND AOA 30 KTS EXPECTED AT ALL TAF SITES AFTER 15Z WEDNESDAY AS COLDER AIR MOVES IN ALOFT AND COMBINES WITH LIMITED SFC HEATING THROUGH THE BKN STRATO CU DECK. OUTLOOK... THU...WINDY. AM SHOWERS/LOW CIGS POSSIBLE...MAINLY NW. FRI-SUN...NO SIG WX EXPECTED. && .HYDROLOGY... RAINFALL AMOUNTS THROUGH THIS AFTERNOON HAVE GENERALLY RANGED BETWEEN 1 AND 2 INCHES. MINOR FLOODING DUE TO CLOGGED STORM DRAINS...PONDING/STANDING WATER WILL LIKELY CONTINUE INTO TONIGHT. MINOR RISES ARE FORECAST ON AREA RIVERS..STREAMS AND CREEKS BUT NO FLOODING IS EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT LONG TERM...STEINBUGL AVIATION...CERU/MARTIN HYDROLOGY...
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
703 PM CDT WED OCT 28 2015 .UPDATE... ISSUED AT 654 PM CDT WED OCT 28 2015 COLD AIR ADVECTION SNOW SHOWERS ARE TAPERING OFF THIS EVENING. ANOTHER BAND OF PRECIP IS MOVING IN FROM THE NORTHEAST AND WILL AFFECT MAINLY THE EASTERN CWA. WINDS HAVE DIMINISHED BELOW ADVISORY CRITERIA. HOWEVER WINDS ARE STILL EXPECTED TO INCREASE ALONG I-29 AGAIN TONIGHT SO HEADLINE POTENTIAL WILL NEED TO BE REEVALUATED. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 343 PM CDT WED OCT 28 2015 SCT SNOW SHOWERS CONTINUE TO MOVE SOUTHEAST ACROSS THE CWA WITH HEAVIER SQUALLS REDUCING VSBY DOWN TO AROUND 1SM AT TIMES. ALSO GETTING REPORTS OF SLEET/RAIN MIXING IN AS WELL. WILL CONTINUE TO SEE THIS ACTIVITY THROUGH SUNSET BEFORE THINGS DIMINISH. WILL THEN BE WATCHING THE VORT LOBE ROTATING SOUTHWARD INTO THE AREA LATER TONIGHT WITH ADDITIONAL LIGHT SNOW CHANCES OVER THE NORTHEAST CORNER OF THE CWA. THIS NEXT ROUND OF LIGHT SNOW MAY BRING SOME LIGHT ACCUMS OR A DUSTING TO THE NORTHEAST CWA...ESPECIALLY IN HIGHER TERRAIN. ALSO WATCHING WIND SPEEDS ACROSS THE AREA. ITS BEEN HIT AND MISS FOR WIND ADVISORY SPEEDS AS MOST AREAS HAVE BEEN FLIRTING WITH IT OR JUST BELOW CRITERIA. WILL LET THE CURRENT HEADLINE REMAIN IN PLACE UNTIL 00Z THOUGH AS A COUPLE 20Z OBS WERE IN LOW END CRITERIA SUSTAINED AND GUSTING CLOSE TO 45 MPH. OVERNIGHT...ANOTHER SURGE OF STRONGER WINDS IS EXPECTED OVER THE NORTHEAST CORNER OF THE CWA AS 925 MB WINDS INCREASE. MAV/LAV GUIDANCE FOR SISSETON ACTUALLY SHOWS SUSTAINED WINDS AROUND 30 KNOTS LATER THIS EVENING...BUT FEEL IT WILL BE LIKELY LOCALIZED TO SISSETON AND THE HIGHER ELEVATIONS NEAR SISSETON. PEEVER AND SUMMIT MAY SEE THE STRONGER WINDS AS WELL...BUT UNCERTAIN JUST HOW WIDESPREAD THE NEXT SURGE WILL BE TO WARRANT EXTENDING A WIND ADVISORY FOR A SMALL PORTION OF THE NORTHEAST CWA THROUGH 06Z OR 09Z. WILL LEAVE THIS DECISION FOR EVENING SHIFT. SPS MAY BE ABLE TO HANDLE THINGS AS WELL IF IT IS MORE OF A LOCALIZED EVENT. CLOUDS ARE THE NEXT ISSUE. STILL A WEALTH OF CLOUDS MOVING SOUTHWARD INTO THE AREA AND FEEL MUCH OF THE NIGHT WILL BE CLOUDY OR MOSTLY CLOUDY. AFTER SUNSET THERE SHOULD BE SOME EROSION OF THE CLOUDS ALONG THE WESTERN END. HARD TO DETERMINE JUST WHEN THE CLOUDS BEGIN TO DEPART/CLEAR OUT...BUT DID GO FOR A CLEARING TREND OVER CENTRAL SD AFTER MIDNIGHT. THIS MAY NOT BE THE CASE THOUGH GIVEN UPSTREAM TRENDS SO EVENING SHIFT MAY NEED TO ADJUST CLOUD COVER. RAP 925-850 RH ACTUALLY KEEPS HIGH VALUES OVER MUCH OF THE CWA THE ENTIRE NIGHT. WITH THE CLOUDS AND WINDS STAYING IN PLACE...TEMPS WILL NOT FALL A HUGE AMOUNT. REST OF THE SHORT TERM IS RATHER QUIET AS A SFC HIGH MOVES OVER THE AREA ON THURSDAY. THIS WILL BRING LIGHTER WINDS...ESPECIALLY BY AFTERNOON/EVENING. LOWS STILL TRICKY TO FORECAST THURSDAY NIGHT AS THE SFC HIGH MOVES OFF PRETTY QUICKLY AND RETURN FLOW SOUTHERLY WINDS AND WARM AIR ADVECTION ARE ALREADY ONGOING BY 12Z FRIDAY. WILL PROBABLY HAVE A SHARP DROP IN THE EVENING THEN SEE READINGS STEADY OFF OR EVEN RISE A FEW DEGREES AS WINDS INCREASE AND HIGH LEVEL CLOUDS MOVE IN. ALTHOUGH...AS WE TYPICALLY SEE VERY OFTEN...FAVORED COLD SPOTS AND VALLEYS WILL LIKELY NOT TAP INTO THE STRONGER WINDS AND STAY AROUND 5 KNOTS OR SO WHICH WILL ALLOW FOR TEMPS TO FALL QUITE NICELY. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 343 PM CDT WED OCT 28 2015 NEAR ZONAL FLOW ALOFT IS EXPECTED THROUGH THE FIRST HALF OF THE LONG TERM FORECAST. MODELS DO SHOW A COUPLE OF SHORTWAVES SKIRTING JUST NORTH OF THE REGION...BUT THE FORECAST REMAINS LARGELY DRY FOR OUR CWA. THE FLOW WILL TRANSITION TO THE SOUTHWEST AS A LONG WAVE TROUGH MOVES OVER THE WESTERN CONUS BY EARLY NEXT WEEK. MODEL SOLUTIONS BEGIN TO SHOW SOME DISCREPANCIES BY THIS POINT...BUT PRECIPITATION CHANCES RETURN TO THE FORECAST BY THE TUESDAY/WEDNESDAY TIME FRAME REGARDLESS. THE MILD PACIFIC FLOW WILL ENSURE ABOVE NORMAL TEMPERATURES. IN FACT BY SUNDAY AND MONDAY 850 TEMPS ARE PROGGED IN THE TEENS...AND CURRENT FORECAST HIGH TEMPERATURES WILL BE PUSHING 15 TO 20 DEGREES ABOVE NORMAL. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 654 PM CDT WED OCT 28 2015 VFR CONDITIONS CURRENTLY PREVAIL ACROSS THE REGION. HOWEVER MVFR CIGS ARE EXPECTED TO ADVECT IN THIS EVENING AND AFFECT KABR AND KATY. WINDS WILL SLOWLY DIMINISH OVERNIGHT AND SKIES WILL CLEAR BY THU AFTERNOON. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...WISE SHORT TERM...TMT LONG TERM...SERR AVIATION...WISE
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
835 PM CDT WED OCT 28 2015 .UPDATE... LATEST RADAR IMAGERY SHOWS PRECIP HAS EXITED THE AREA ATTM. HOWEVER...ALL MODELS INCLUDING THE LATEST HRRR SHOW ADDITIONAL ISOLATED SHOWERS MOVING ACROSS THE CWA LATER THIS EVENING AND OVERNIGHT AS COLD FRONT APPROACHES THE AREA. THUS WILL SHOW A SLIGHT CHANCE POP FOR ALL ZONES THROUGH 06Z...THEN JUST THE SOUTHEAST HALF AFTER 06Z. WITH THE VERY MOIST GROUNDS FROM THE RECENT RAINFALL...SKIES CLEARING OUT AND WINDS BECOMING LIGHT...ALSO EXPECT PATCHY FOG TO DEVELOP AREAWIDE AFTER MIDNIGHT. REST OF FORECAST IS ON TRACK. SHAMBURGER && .PREV DISCUSSION... UPDATE... FOR 00Z AVIATION. DISCUSSION... A WEAKENING UPPER LEVEL LOW WILL MOVE THRU THE MID SOUTH THIS EVENING AND HELP TOUCH OFF A FEW LIGHT SHOWERS THE REST OF THIS AFTERNOON AND THE FIRST HALF OF TONIGHT. SKIES MAY CLEAR ENOUGH BEHIND THE SYSTEM TO ALLOW PATCHY FOG TO FORM AROUND SUNRISE... ESPECIALLY SINCE THE GROUND IS WET AND SURFACE WIND WILL BE LIGHT. EXPECT ZONAL H5 FLOW THURSDAY AS A DEEP LOW MOVES THRU THE GREAT LAKES...THEN RIDGING ACROSS OUR REGION ON FRIDAY. THIS WILL HELP BRING DRIER AND SUNNIER WEATHER BOTH DAYS. TEMPS WILL BE DOWN A LITTLE ON THURSDAY BEHIND THE WEAK COLD FRONT. IT WILL BE PRETTY CHILLY FRIDAY MORNING UNDER FAIR SKIES AND CALM WINDS THANKS TO A SFC RIDGE POSITIONED RIGHT OVER MIDDLE TN. H5 RIDGE AXIS WILL PASS ACROSS THE AREA FRIDAY EVENING...WITH SOUTHWEST FLOW ALOFT DEVELOPING THRU THE ENTIRE WEEKEND AHEAD OF A WEAKENING TROUGH THAT WILL MOVE FROM TX TOWARD TN. THIS PATTERN WILL INCREASE MOISTURE ACROSS THE MID STATE ON SATURDAY AND ESPECIALLY ON SUNDAY WITH A DECENT SHOT AT RAIN BOTH DAYS. INCLUDED ISOLATED THUNDER IN THE FORECAST SUNDAY AND SUNDAY NIGHT AS INSTABILITY APPEARS TO BE BEST DURING THAT TIME. RAIN CHANCES WILL DECREASE FROM WEST TO EAST ON MONDAY AS THE WEAKENING H5 TROUGH MOVES OFF TO OUR EAST. NO REAL PUNCH OF COLD AIR IS NOTED BEHIND THIS DEPARTING SYSTEM. IN FACT...TEMPS SHOULD BE ABOVE AVERAGE NEXT TUESDAY AND WEDNESDAY AS H5 HIGH PRESSURE BUILDS OVER THE SOUTHEASTERN U.S. THE RIDGE SHOULD ALSO KEEP US RAIN FREE TUESDAY AND WEDNESDAY. AVIATION... 00Z TAF DISCUSSION. VFR CONDITIONS SHOULD DOMINATE THIS TAF CYCLE...WITH SOME MVFR FOG POSSIBLE AT KCKV AND KBNA. MODELS ARE HINTING AT MVFR/IFR CLOUD DECK RETURNING TO KCSV LATER THIS EVENING AND OVERNIGHT...BUT SHOULD BURN OFF DURING THE EARLY MORNING. WINDS MAY PICK UP OUT OF THE WEST TOMORROW TO AROUND 10 KNOTS OR SO DURING THE AFTERNOON AS WELL. OHX WATCHES/WARNINGS/ADVISORIES... NONE. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 50 68 40 64 / 20 10 10 0 CLARKSVILLE 46 63 38 61 / 20 0 10 0 CROSSVILLE 52 65 37 60 / 20 10 10 0 COLUMBIA 48 69 36 65 / 20 0 10 0 LAWRENCEBURG 50 68 39 65 / 20 0 10 0 WAVERLY 48 65 40 62 / 20 0 10 0 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 55
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1258 AM CDT TUE OCT 27 2015 .AVIATION... ALL TERMINALS ARE CURRENTLY VFR. DEL RIO AND SAN ANTONIO WILL REMAIN VFR THROUGH THIS PERIOD. THE DEW POINT DEPRESSION AT AUS IS ALREADY ONLY TWO DEGREES...SO I THINK FOG WILL FORM IN THE NEXT FEW HOURS REDUCING VIS TO MVFR UNTIL AFTER SUNRISE. OTHERWISE THEY WILL BE VFR. WINDS WILL BE LIGHT TODAY SHIFTING TO SOUTHWESTERLY THIS AFTERNOON. && .PREV DISCUSSION... /ISSUED 252 PM CDT MON OCT 26 2015/ SHORT TERM (TONIGHT THROUGH TUESDAY)... NO HIGHLIGHTS OR HAZARDS EXPECTED THROUGH THE NEXT FEW DAYS WITH A DRY AIRMASS IN PLACE AS NEAR NORMAL TEMPERATURES ARE EXPECTED. CURRENT WATER VAPOR AND RAP ANALYSIS DEPICT A STRONG CLOSED MID LEVEL LOW TRAVERSING EAST ACROSS THE NORTHERN GULF OF MEXICO AWAY FROM THE REGION. FARTHER UPSTREAM TO THE WEST...A DAMPENED TROUGH IS SHIFTING ACROSS THE INTER-MOUNTAIN WEST THAT WILL EVENTUALLY BRING A WEAK FRONT TOWARDS THE REGION BY MID WEEK. FOR TODAY...WINDY AND WARM TEMPERATURES ARE ONGOING AS A TIGHT PRESSURE GRADIENT EXISTS FROM WEST TO EAST TOWARDS THE AFOREMENTIONED LOW PRESSURE SYSTEM IN THE GULF. WINDS WILL GUST TO 20-25 MPH AT TIMES AS TEMPS MAX OUT IN THE MID 70S TO LOW 80S. WINDS WILL DECREASE OVERNIGHT AS THE LOW PULLS AWAY AND WITH DEWPOINTS EXPECTED IN THE UPPER 40S AND LOW 50S OVERNIGHT WITH CLEARING SKIES...TEMPS WILL DROP INTO THE UPPER 40S IN THE HILL COUNTRY AND LOW TO MID 50S ACROSS THE I-35 CORRIDOR AND COASTAL PLAINS. A NEAR REPEAT OF CONDITIONS IS EXPECTED TOMORROW WITH SLIGHTLY WARMER MAX HIGHS AND LESS CLOUD COVER GIVEN DRIER VERTICAL PROFILES FROM MODEL SOUNDINGS. LONG TERM (WEDNESDAY THROUGH MONDAY)... OUR HAZARD FOCUS THIS PERIOD WILL BE ON FRIDAY AFTERNOON THROUGH SATURDAY AFTERNOON AS ANOTHER POTENT STORM SYSTEM WILL APPROACH THE REGION. THE MAIN RISKS AT THIS POINT LOOK TO BE ANOTHER ROUND OF HEAVY RAIN BUT WILL NEED TO MONITOR EVOLUTION FOR OTHER POTENTIAL SEVERE WEATHER HAZARDS. BY MID-WEEK...NORTH WINDS WILL CONTINUE AS A WEAK DRY FRONT MOVES TOWARDS THE REGION DUE TO A WEAK SHORTWAVE TROUGH SHIFTING ACROSS THE SOUTHERN PLAINS. HOWEVER...BY THURSDAY...WINDS WILL BEGIN TO VEER TO THE EAST AND THEN SOUTHEAST AS THE RE-ESTABLISHING OF MOISTURE COMMENCES. A STRONG SIGNAL ACROSS THE ENSEMBLE SUITE OF GLOBAL MODELS INDICATES A POTENT MID-LVL TROUGH MOVING INTO NORTHERN MEXICO BY THURSDAY. THIS FEATURE...ALONG SIDE BROAD TROUGHING OVER THE PLAINS...WILL HELP INDUCE LEE-SIDE SURFACE CYCLOGENESIS THAT WILL AID IN DEEPER SOUTHERLY FLOW. BY MID-DAY FRIDAY...THE TROUGH OVER SOUTHERN ARIZONA WILL HAVE DEEPENED SUBSTANTIALLY TO NEAR 560 DM WHICH IS ABOUT 10DM DEEPER THAN THE PREVIOUS TROUGH THAT IMPACTED THE REGION. HOWEVER...WE WILL HAVE LESS MOISTURE TO WORK WITH THIS UPCOMING WEEKEND VS. THE PAST EVENT WHERE PWATS WERE UPWARDS OF 2.1-2.3" VS. THE PROGGED 1.8-1.9` (BUT STILL GOOD). THESE VALUES WILL STILL BE ADEQUATE ENOUGH FOR HEAVY RAIN AS SET-UP LOOKS TO BE SLIGHTLY STRONGER FORCED. IT IS TOO EARLY TO TELL IF THERE WILL BE MULTIPLE WAVES FRIDAY AFTERNOON AND AGAIN SATURDAY AS A POSSIBLE DRYLINE SURGE OCCURS OR IF IT WILL BE A MORE PROLONGED EVENT LATE FRIDAY INTO MID-DAY SATURDAY. LOOKING AT PROGGED CAPE/SHEAR COMBINATIONS AND SOUNDINGS...HEALTHY PARAMETERS APPEAR TO BE IN PLACE THAT COULD SUGGEST ORGANIZATION FOR A BROKEN QLCS ALONG A POSSIBLE DRYLINE SURGE SATURDAY MORNING TO MID-DAY. ANY ORGANIZATION THAT DOES OCCUR COULD AID IN STRONG WINDS AND POSSIBLY OTHER HAZARDS AS A 90-100 KT JET STREAK WILL SUPPORT STRONG UPPER-LEVEL DIVERGENCE NEAR AND NORTH OF THE REGION. WILL CONTINUE TO MONITOR THE SET-UP FOR OVERALL RAIN ACCUMULATION AMOUNTS AND SEVERE WEATHER HAZARD POSSIBILITIES. THE TIMING OF THE SYSTEM MOVING THROUGH BECOMES MURKY ON SUNDAY WITH EC SLOWER THAN THE PROGRESSIVE GFS. THE UKMET AND GEM FAVOR A SLOWER PATTERN WITH RAIN POSSIBLY LINGERING INTO SUNDAY. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 81 62 81 56 78 / 0 0 0 0 - AUSTIN BERGSTROM INTL AIRPORT 81 56 82 52 79 / 0 0 0 0 - NEW BRAUNFELS MUNI AIRPORT 82 59 85 55 80 / 0 0 0 0 - BURNET MUNI AIRPORT 79 57 78 53 76 / 0 0 0 0 - DEL RIO INTL AIRPORT 82 57 83 55 80 / 0 0 0 0 - GEORGETOWN MUNI AIRPORT 79 57 80 52 77 / 0 0 0 0 - HONDO MUNI AIRPORT 82 56 86 54 81 / 0 0 0 0 - SAN MARCOS MUNI AIRPORT 81 57 83 55 79 / 0 0 0 0 - LA GRANGE - FAYETTE REGIONAL 80 58 83 56 80 / 0 0 0 0 - SAN ANTONIO INTL AIRPORT 83 61 85 56 80 / 0 0 0 0 - STINSON MUNI AIRPORT 83 59 86 57 81 / 0 0 0 0 - && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...05 SYNOPTIC/GRIDS...HAMPSHIRE
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1130 PM EDT WED OCT 28 2015 .SYNOPSIS... ONE FRONT MOVES ACROSS THIS EVENING FOLLOWED BY ANOTHER FRONT THURSDAY WHICH WILL BRING DRIER WEATHER. HIGH PRESSURE ARRIVES THURSDAY NIGHT INTO FRIDAY FROM THE WEST. THIS HIGH WILL MOVE OFFSHORE THIS WEEKEND WHILE ANOTHER LOW PRESSURE AREA FORMS OVER THE LOWER MISSISSIPPI VALLEY BRING MORE MOISTURE OUR WAY SUNDAY INTO MONDAY. && .NEAR TERM /THROUGH THURSDAY NIGHT/... AS OF 1130 PM EDT WEDNESDAY... A MAJORITY OF THE SHOWERS HAVE MOVED EAST OUT OF THE FORECAST AREA. LATEST HRRR SHOWED AN AREA OF PRECIPITATION IN THE FAR SOUTHWEST COUNTY WARNING AREA THROUGH 06Z/2AM...OTHERWISE THE DRYING TREND WILL CONTINUE. HAVE TRIMMED BACK THE PROBABILITY OF PRECIPITATION TO REFLECT THE LATEST RADAR TRENDS. SINCE FRONT WILL NOT REACH WESTERN COUNTIES OF THE FORECAST AREA UNTIL AFTER 6AM...HAVE ADJUSTED THE MINIMUM TEMPERATURES A FEW DEGREES WARMER. WE SHOULD REACH A POINT WHERE DRIER AIR WILL MOVE IN FROM THE SOUTHWEST CLEARING THINGS OUT LEE OF THE BLUE RIDGE...FOLLOWED BY LINGERING UPSLOPE SE WV/FAR SW VA/NW NC OVERNIGHT INTO THURSDAY. MAY SEE ANOTHER SHOT OF SHOWERS THURSDAY IN THE SE WV MTNS TOWARD NC...BUT EAST OF THIS WILL SEE MORE SUNSHINE. THE NAM IS ACTUALLY KEEPING THE SHOWER THREAT MOVING EAST OF THE MTNS INTO NC THURSDAY AFTERNOON. FOR NOW I WILL KEEP IT DRY WITH SOME CLOUD COVER LINGERING HERE. NW WINDS WILL BE GUSTY LATE TONIGHT-THURSDAY BUT ONLY IN THE 20-30 MPH RANGE. LOWS TONIGHT WILL BE ELEVATED AHEAD OF THE FRONT STAYING IN THE 50S...WITH SOME 40S BY MORNING OVER THE HIGHER RIDGES. DESPITE BEING POST-FRONT THURSDAY...THE UPPER FLOW REMAINS SW WITH AXIS OF NEGATIVE TILT TROUGH OVER THE MID ATLANTIC WITH YET ANOTHER VORT MOVING ACROSS THE OHIO VALLEY. NW FLOW AT TIMES WITH SUNSHINE WILL WARM THINGS UP IN THE LEE OF THE MTNS...SO EXPECT HIGHS THURSDAY IN THE LOWER 70S EAST OF THE MOUNTAINS...WITH 60S ELSEWHERE. THURSDAY NIGHT...HIGH PRESSURE REMAINS WEST OF THE AREA WITH NW FLOW WEAKENING. LOW LVL THICKNESSES COOL ENOUGH THAT LOWS WILL RANGE FROM THE MID TO UPPER 30S MOUNTAINS...TO LOWER 40S PIEDMONT. && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... AS OF 310 PM EDT WEDNESDAY... THE LARGE HIGH PRESSURE OVER THE MID MISS VALLEY WILL MOVE EAST FRIDAY AND WE SHOULD SEE PLENTY OF SUNSHINE. COOLER AIR WILL FILTER INTO THE REGION AS THE UPPER LEVEL TROUGH TRACKS EAST OF THE OHIO VALLEY. TEMPERATURES WILL FAIL TO REACH SEASONAL LEVELS FRIDAY AS COOLER AIR CONTINUES TO PUSH INTO THE REGION. SATURDAY MORNING TEMPERATURES WILL BE IN THE 30S WITH SOME MOUNTAINS LOCATIONS DROPPING INTO THE UPPER 20S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 320 PM EDT WEDNESDAY... THIS FORECAST TURNS MORE TOWARD SW FLOW ALOFT WITH A SPLIT FLOW PATTERN...WITH TEMPERATURES MODERATING. UPPER TROUGH OVER THE LOWER MISS VALLEY SUNDAY WILL HEAD INTO THE MOUNTAINS BY MONDAY BRINGING A GOOD CHANCE OF SHOWERS. DIFFERENCES ON TIMING OF SHOWER CHANCES EXISTS...WITH SOME MODELS SHOWING SHOWERS ARRIVING BY SUNDAY MORNING INTO THE MOUNTAINS. WILL INTRODUCE LOW CHANCE POPS LATE SAT NIGHT INTO THE MOUNTAINS...WITH BETTER CHANCE WORKING SW TO NE SUNDAY AFTERNOON. BY LATE MONDAY NIGHT TO TUESDAY THE FRONTAL BOUNDARY SHOULD BE EXITING TO OUR SE...BUT FLOW AROUND THE HIGH PRESSURE OVER THE NEW ENGLAND COAST MAY KEEP SHOWERS GOING AIDED BY ATLANTIC MOISTURE OVERRIDING THE FRONT FROM GEORGIA TO NC OUTER BANKS. WILL STAY WITH LOW POPS TUESDAY WITH COOLER TEMPS. BY WEDNESDAY...THE HIGHS STARTS TO MOVE SOUTHEAST OFF THE MID ATLANTIC COAST. ATTM WILL KEEP IT MAINLY DRY WITH DEEPER MOISTURE MOVING TO THE COAST AND OFFSHORE. && .AVIATION /04Z THURSDAY THROUGH MONDAY/... AS OF 730 PM EDT WEDNESDAY... COLD FRONT EXTENDED FROM MICHIGAN TO ARKANSAS. AHEAD OF THE FRONT BANDS OF SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TONIGHT. NAM/GFS/RAP AND HRRR MODELS WERE IN GOOD AGREEMENT MOVING THE LAST BAND OF SHOWERS THAT WAS CURRENTLY OVER THE MOUNTAINS...EAST OF KLYH AND KDAN BY 04Z/MIDNIGHT. ALSO HAD CONSISTENT TIMING OF PASSAGE OF COLD FRONT AROUND 12Z/8AM IN THE MOUNTAINS AND IN THE AFTERNOON EAST OF THE BLUE RIDGE. BEHIND THIS LAST BAND OF SHOWERS WINDS BECOME WEST THROUGH A DEEP LAYER AS SEEN ON BUFKIT. HAVE ADDED A FEW HOURS OF VFR CEILINGS IN AT KLWB AND KBLF AROUND 01-04Z/9PM-MIDNIGHT BUT WITH ONLY MEDIUM CONFIDENCE. LATER TONIGHT LOW LEVEL MOISTURE WILL FILL BACK IN OVER THE TYPICAL WESTERN UPSLOPE AREAS AND KLWB AND KBLF WILL AGAIN HAVE MVFR CEILINGS. HAVE ALSO REMOVED SOME OF THE GUSTY WINDS UNTIL THURSDAY. BEHIND THE FRONT BUFKIT WAS SHOWING ENOUGH MOMENTUM TRANSFER FOR WIND GUSTS FROM THE WEST AT 20 TO 25 KNOTS ONCE MIXING BEGINS. CONDITIONS WILL IMPROVE EAST OF THE BLUE RIDGE...WITH VFR CLOUDS BECOMING SCATTERED ON THURSDAY DUE TO DRIER AIR MOVING INTO THE REGION AND A DEEP WEST DOWNSLOPE WIND. EXTENDED AVIATION DISCUSSION... IMPROVING CONDITIONS ARE EXPECTED FRI AS HIGH PRESSURE SPREADS ACROSS THE REGION WITH MOSTLY VFR CONDITIONS. WINDS WILL DIMINISH FRIDAY. THE NEXT CHANCE FOR RAIN AND SUB-VFR CIGS WILL COME SUNDAY-MONDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...WP NEAR TERM...AMS/CF/WP SHORT TERM...RCS/WP LONG TERM...MBS/WP AVIATION...AMS/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
746 PM EDT WED OCT 28 2015 .SYNOPSIS... ONE FRONT MOVES ACROSS THIS EVENING FOLLOWED BY ANOTHER FRONT THURSDAY WHICH WILL BRING DRIER WEATHER. HIGH PRESSURE ARRIVES THURSDAY NIGHT INTO FRIDAY FROM THE WEST. THIS HIGH WILL MOVE OFFSHORE THIS WEEKEND WHILE ANOTHER LOW PRESSURE AREA FORMS OVER THE LOWER MISSISSIPPI VALLEY BRING MORE MOISTURE OUR WAY SUNDAY INTO MONDAY. && .NEAR TERM /THROUGH THURSDAY NIGHT/... AS OF 630 PM EDT WEDNESDAY... LINE OF STRONGER SHOWERS IS CURRENTLY MOVING THROUGH THE NRV AND THE GREENBRIER VALLEY. MENTIONED ISOLATED THUNDER FOR THE NEXT COUPLE OF HOURS IN THIS AREA. LINE OF CONVECTION IS CURRENTLY FORMING ACROSS CENTRAL NC DOWN THROUGH EASTERN SC. THUS FAR NOTHING SIGNIFICANT HAS MATERIALIZED ACROSS OUR PIEDMONT AREA BUT THERE IS STILL SUFFICIENT SHEAR TO WARRANT SPC KEEPING OUR FAR SE COUNTIES IN THE MARGINAL RISK FOR SEVERE WX. ALL OTHER PREVIOUS DISCUSSION DETAILS REMAIN INTACT. AS OF 250 PM EDT WEDNESDAY... LOCAL RADAR SHOWS EMBEDDED HEAVIER SHOWERS TRAVERSING THE PIEDMONT OF VIRGINIA...WITH ANOTHER MODERATE AREA BETWEEN BLF-EKN WV. THE LATEST HRRR/WRF SHOWING 2-3 BANDS POSSIBLY MOVING ACROSS THE AREA THROUGH THE EVENING. QUESTION REMAINS SVR THREAT. REGIONAL RADAR IS NOT THAT IMPRESSIVE ATTM UPSTREAM...BUT WILL HAVE TO SEE IF THE BREAKS IN THE CLOUD COVER DEVELOPING OVER THE NEW RIVER VALLEY SWD INTO THE TRIAD WILL MAKE IT EAST AND DESTABILIZE THE PIEDMONT AHEAD OF THE UPPER TROUGH. NOT OUT OF THE QUESTION THAT SOME CELLS WILL BRING STRONG WIND GUSTS...BUT EVEN SO...THIS TIME OF YEAR...WITH WEDGES SLOW TO CLEAR OUT...WE ARE GETTING HARD PRESSED FOR ANY BIG THREAT OF SVR. WILL MAINTAIN ISOLATED WORDING IN THE HWO...AS WE STILL HAVE THE BETTER DYNAMICS TO DEAL BETWEEN 00Z-06Z. FOR NOW I WILL KEEP MOST IF ANY THUNDER WORDING LEE OF THE BLUE RIDGE...WITH MODERATE SHOWERS INTO EARLY EVENING...THEN WE SHOULD REACH A POINT WHERE DRIER AIR WILL MOVE IN FROM THE SOUTHWEST CLEARING THINGS OUT LEE OF THE BLUE RIDGE...FOLLOWED BY LINGERING UPSLOPE SE WV/FAR SW VA/NW NC OVERNIGHT INTO THURSDAY. MAY SEE ANOTHER SHOT OF SHOWERS THURSDAY IN THE SE WV MTNS TOWARD NC...BUT EAST OF THIS WILL SEE MORE SUNSHINE. THE NAM IS ACTUALLY KEEPING THE SHOWER THREAT MOVING EAST OF THE MTNS INTO NC THURSDAY AFTERNOON. FOR NOW I WILL KEEP IT DRY WITH SOME CLOUD COVER LINGERING HERE. NW WINDS WILL BE GUSTY LATE TONIGHT-THURSDAY BUT ONLY IN THE 20-30 MPH RANGE. LOWS TONIGHT WILL BE ELEVATED AHEAD OF THE FRONT STAYING IN THE 50S...WITH SOME 40S BY MORNING OVER THE HIGHER RIDGES. DESPITE BEING POST-FRONT THURSDAY...THE UPPER FLOW REMAINS SW WITH AXIS OF NEGATIVE TILT TROUGH OVER THE MID ATLANTIC WITH YET ANOTHER VORT MOVING ACROSS THE OHIO VALLEY. NW FLOW AT TIMES WITH SUNSHINE WILL WARM THINGS UP IN THE LEE OF THE MTNS...SO EXPECT HIGHS THURSDAY IN THE LOWER 70S EAST OF THE MOUNTAINS...WITH 60S ELSEWHERE. THURSDAY NIGHT...HIGH PRESSURE REMAINS WEST OF THE AREA WITH NW FLOW WEAKENING. LOW LVL THICKNESSES COOL ENOUGH THAT LOWS WILL RANGE FROM THE MID TO UPPER 30S MOUNTAINS...TO LOWER 40S PIEDMONT. && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... AS OF 310 PM EDT WEDNESDAY... THE LARGE HIGH PRESSURE OVER THE MID MISS VALLEY WILL MOVE EAST FRIDAY AND WE SHOULD SEE PLENTY OF SUNSHINE. COOLER AIR WILL FILTER INTO THE REGION AS THE UPPER LEVEL TROUGH TRACKS EAST OF THE OHIO VALLEY. TEMPERATURES WILL FAIL TO REACH SEASONAL LEVELS FRIDAY AS COOLER AIR CONTINUES TO PUSH INTO THE REGION. SATURDAY MORNING TEMPERATURES WILL BE IN THE 30S WITH SOME MOUNTAINS LOCATIONS DROPPING INTO THE UPPER 20S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 320 PM EDT WEDNESDAY... THIS FORECAST TURNS MORE TOWARD SW FLOW ALOFT WITH A SPLIT FLOW PATTERN...WITH TEMPERATURES MODERATING. UPPER TROUGH OVER THE LOWER MISS VALLEY SUNDAY WILL HEAD INTO THE MOUNTAINS BY MONDAY BRINGING A GOOD CHANCE OF SHOWERS. DIFFERENCES ON TIMING OF SHOWER CHANCES EXISTS...WITH SOME MODELS SHOWING SHOWERS ARRIVING BY SUNDAY MORNING INTO THE MOUNTAINS. WILL INTRODUCE LOW CHANCE POPS LATE SAT NIGHT INTO THE MOUNTAINS...WITH BETTER CHANCE WORKING SW TO NE SUNDAY AFTERNOON. BY LATE MONDAY NIGHT TO TUESDAY THE FRONTAL BOUNDARY SHOULD BE EXITING TO OUR SE...BUT FLOW AROUND THE HIGH PRESSURE OVER THE NEW ENGLAND COAST MAY KEEP SHOWERS GOING AIDED BY ATLANTIC MOISTURE OVERRIDING THE FRONT FROM GEORGIA TO NC OUTER BANKS. WILL STAY WITH LOW POPS TUESDAY WITH COOLER TEMPS. BY WEDNESDAY...THE HIGHS STARTS TO MOVE SOUTHEAST OFF THE MID ATLANTIC COAST. ATTM WILL KEEP IT MAINLY DRY WITH DEEPER MOISTURE MOVING TO THE COAST AND OFFSHORE. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... AS OF 730 PM EDT WEDNESDAY... COLD FRONT EXTENDED FROM MICHIGAN TO ARKANSAS. AHEAD OF THE FRONT BANDS OF SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TONIGHT. NAM/GFS/RAP AND HRRR MODELS WERE IN GOOD AGREEMENT MOVING THE LAST BAND OF SHOWERS THAT WAS CURRENTLY OVER THE MOUNTAINS...EAST OF KLYH AND KDAN BY 04Z/MIDNIGHT. ALSO HAD CONSISTENT TIMING OF PASSAGE OF COLD FRONT AROUND 12Z/8AM IN THE MOUNTAINS AND IN THE AFTERNOON EAST OF THE BLUE RIDGE. BEHIND THIS LAST BAND OF SHOWERS WINDS BECOME WEST THROUGH A DEEP LAYER AS SEEN ON BUFKIT. HAVE ADDED A FEW HOURS OF VFR CEILINGS IN AT KLWB AND KBLF AROUND 01-04Z/9PM-MIDNIGHT BUT WITH ONLY MEDIUM CONFIDENCE. LATER TONIGHT LOW LEVEL MOISTURE WILL FILL BACK IN OVER THE TYPICAL WESTERN UPSLOPE AREAS AND KLWB AND KBLF WILL AGAIN HAVE MVFR CEILINGS. HAVE ALSO REMOVED SOME OF THE GUSTY WINDS UNTIL THURSDAY. BEHIND THE FRONT BUFKIT WAS SHOWING ENOUGH MOMENTUM TRANSFER FOR WIND GUSTS FROM THE WEST AT 20 TO 25 KNOTS ONCE MIXING BEGINS. CONDITIONS WILL IMPROVE EAST OF THE BLUE RIDGE...WITH VFR CLOUDS BECOMING SCATTERED ON THURSDAY DUE TO DRIER AIR MOVING INTO THE REGION AND A DEEP WEST DOWNSLOPE WIND. EXTENDED AVIATION DISCUSSION... IMPROVING CONDITIONS ARE EXPECTED FRI AS HIGH PRESSURE SPREADS ACROSS THE REGION WITH MOSTLY VFR CONDITIONS. WINDS WILL DIMINISH FRIDAY. THE NEXT CHANCE FOR RAIN AND SUB-VFR CIGS WILL COME SUNDAY-MONDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...WP NEAR TERM...CF/WP SHORT TERM...RCS/WP LONG TERM...MBS/WP AVIATION...AMS/WP Area Forecast Discussion National Weather Service Spokane WA 513 PM PDT WED OCT 28 2015 .SYNOPSIS... Light rain will move into the region tonight and taper off on Thursday. This break period will end on Friday as a deep fetch of Pacific moisture feeds into the region promoting widespread rain on Friday and into Saturday. Windy and gusty conditions will also develop for a damp and blustery Halloween. Unsettled conditions with occasional wet periods will continue into next week. && .DISCUSSION... Quick update to the forecast for tonight. Radar shows the anticipated precipitation is moving across the Basin. Yakima, Ellensburg, Wenatchee, and Omak have all measured a few hundredths of an inch so far. Best area of rain looks to be moving into the Basin between Ephrata and Tri-Cities. Radar trends agree for the most part with the NAM and HRRR models, although the HRRR does seem a tad slow. Light steady rain should reach the WA/ID border cities around 10 or 11 pm with sprinkles possible before then. Rain will only last for a few hours. Low clouds and some fog will form in the wake of the rain, east of a Republic-to-Lewiston line, and these will persist into Thursday morning. RJ && .AVIATION... 00Z TAFS: A weak but moist front will move over the region this evening and overnight. This will bring light rain to all of the TAF sites. Only the KGEG/KSFF/KCOE/KPUW sites are expected to have IFR weather from this. This will begin as the rain ends in the middle of the night and continue through the morning hours in the form of a low stratus cloud deck, which should dissipate around noon. There are currently bands of showers over western WA/OR and some of these may be able to survive the trip across the Cascades and bring renewed precipitation chances in the morning. But these typically don`t amount to much so they were left out of the TAFs. RJ && .PREV DISCUSSION... /issued 438 PM PDT WED OCT 28 2015/ SYNOPSIS... Light rain will move into the region tonight and taper off on Thursday. This break period will end on Friday as a deep fetch of Pacific moisture feeds into the region promoting widespread rain on Friday and into Saturday. Windy and gusty conditions will also develop for a damp and blustery Halloween. Unsettled conditions with occasional wet periods will continue into next week. Light rain will move into the region tonight and taper off on Thursday. This break period will end on Friday as a deep fetch of Pacific moisture feeds into the region promoting widespread rain on Friday and into Saturday. Windy and gusty conditions will also develop for a damp and blustery Halloween. Unsettled conditions with occasional wet periods will continue into next week. DISCUSSION... Tonight and Thursday...The pattern change is underway with the gradual de-amplification of the long-wave ridge and it being replaced with a more progressive zonal flow. The weak occluded frontal zone currently associated with a north to south oriented band of precipitation working its way from west to east is weakening some as it moves through the forecast area. The weakening is more or less justifying the rather light precipitation amounts in the forecast coupled with the high pops. Given the progressive nature of the forecast for the next 24 hours forecast temperatures remain on a bit on the warm side of climo for this time of year. /Pelatti Thursday night through Saturday night...A wet and windy autumnal pattern is shaping up for this period featuring a good hosing from a subtropical atmospheric river enhancing over a series of transient fronts Friday and Saturday. Snow levels will remain in the 6000 foot range as an air mass able to support this 1 inch or so PWAT stream will necessarily be warmer than average and promote warmer than average surface temperatures through the period. Storm total rainfall from Friday through Saturday night...according to a blend of the suite of current model guidance...suggests one to two inches in the Idaho Panhandle and Cascades with a general one third to 1/2 inch or more in the basin...except a tenth or so in the downslope deep basin area. Thursday night will witness the departure of the initial outriding short wave with decreasing showers mainly over the Idaho Panhandle. Friday morning will feature a moist air mass with light winds...and despite mid level cloud cover there is a good chance of at least patchy fog in valleys. Friday the incoming atmospheric river will arrive and enhance isentropically over the first warm front providing some substantial rainfall and high mountain snow for most of the region. Winds will become breezy out of the southwest as this initial warm front passes through. The fetch will become more favorably directed and established Friday night and Saturday with another warm front and round of sustained stratiform rain...but the deep basin zones will experience a minor rain shadow effect in the overall fast westerly flow regime driving the fetch into the region. Winds will be a significant issue starting Friday and lasting through Saturday with gust potential in the well mixed warm sector potentially approaching 40 mph over exposed terrain. A weak cold occluded front will round out the frontal parade during the day Saturday. The all important Trick-or-Treat period for the youngsters may occur as the air mass dries out after this FROPA over much of the area...showery but not a total rain out...but still quite windy and blustery over the region. /Fugazzi AVIATION... 00Z TAFS: A weak but moist front will move over the region this evening and overnight. This will bring light rain to all of the TAF sites. Only the KGEG/KSFF/KCOE/KPUW sites are expected to have IFR weather from this. This will begin as the rain ends in the middle of the night and continue through the morning hours in the form of a low stratus cloud deck, which should dissipate around noon. There are currently bands of showers over western WA/OR and some of these may be able to survive the trip across the Cascades and bring renewed precipitation chances in the morning. But these typically don`t amount to much so they were left out of the TAFs. RJ 00Z TAFS: A weak but moist front will move over the region this evening and overnight. This will bring light rain to all of the TAF sites. Only the KGEG/KSFF/KCOE/KPUW sites are expected to have IFR weather from this. This will begin as the rain ends in the middle of the night and continue through the morning hours in the form of a low stratus cloud deck, which should dissipate around noon. There are currently bands of showers over western WA/OR and some of these may be able to survive the trip across the Cascades and bring renewed precipitation chances in the morning. But these typically don`t amount to much so they were left out of the TAFs. RJ && .PRELIMINARY POINT TEMPS/POPS... Spokane 43 54 42 56 47 57 / 100 40 10 80 80 80 Coeur d`Alene 43 52 40 52 45 55 / 90 70 20 80 90 90 Pullman 43 55 43 55 46 56 / 100 60 20 80 80 80 Lewiston 46 59 44 61 50 62 / 80 40 20 60 70 70 Colville 42 54 40 53 43 54 / 90 50 10 80 80 70 Sandpoint 42 50 40 52 42 52 / 90 80 30 90 100 100 Kellogg 42 49 39 48 43 51 / 100 80 40 100 100 100 Moses Lake 43 62 44 65 48 62 / 100 20 10 50 40 50 Wenatchee 44 61 43 63 49 61 / 60 20 10 40 30 50 Omak 40 58 39 58 43 57 / 60 20 10 70 50 70 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1224 PM CDT TUE OCT 27 2015 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY ISSUED AT 342 AM CDT TUE OCT 27 2015 FOCUS IN THE SHORT TERM WILL CONTINUE TO BE ON THE TIMING AND DURATION OF STRATIFORM RAIN SHIELD FORECAST TO EVOLVE OVER THE FORECAST AREA...AS NORTHERN AND SOUTHERN STREAM ENERGY CONGEAL OVER THE UPPER MIDWEST AND GREAT LAKES REGION TONIGHT AND WEDNESDAY. IN THE MEANTIME...WEAK MID-LEVEL FRONTOGENETIC FORCING IN CONCERT WITH SUBTLE SHORTWAVE IMPULSES AND SOMEWHAT DEEPER MOISTURE CONTINUES TO GENERATE A PESKY NARROW BAND OF VERY LIGHT RAIN OR SPRINKLES CURRENTLY EXTENDING FROM NORTHCENTRAL WISCONSIN TO NORTHERN MINNESOTA. RAP SEEMS TO HAVE CAPTURED THE BASIC EVOLUTION OF THIS VERY LIGHT PRECIPITATION BAND AND CARRIES IT NORTHWARD INTO UPPER MICHIGAN BY 14 OR 15Z THIS MORNING WHICH SEEMS REASONABLE BASED ON CURRENT TRENDS. NOT GOING TO INCLUDE MENTION OF ANY POPS THIS MORNING FOR THE FAR NORTH AS MEASURABLE AMOUNTS ARE DUBIOUS AT THIS POINT. OTHERWISE...FOR THE REMAINDER OF TODAY EXPECT LOTS OF MID-LEVEL CLOUDINESS WITHIN BROAD AREA OF WEAK ISENTROPIC LIFT. ACROSS NORTHERN WISCONSIN...EXPECT MORE IN THE WAY OF LOW CLOUDS AND SOME PATCHY FOG FOR AT LEAST A COUPLE MORE HOURS EARLY THIS MORNING. DESPITE LOTS OF CLOUDS...TEMPERATURES WILL REMAIN WELL ABOVE NORMAL FOR LATE OCTOBER WITH READINGS MAINLY IN THE 55 TO 60 DEGREE RANGE. THEN FOCUS SHIFTS TO THIS EVENING AND OVERNIGHT...AS SHORTWAVE ENERGY OVER THE CENTRAL PLAINS GRADUALLY CONGEALS WITH MORE POTENT SHORTWAVE DROPPING OUT OF CANADA. SOMEWHAT SURPRISINGLY...SEEMS TO BE FAIRLY DECENT CONSENSUS AMONG THE MODEL GUIDANCE ON THE OVERALL EVOLUTION OF THIS SYSTEM OVER THE NEXT 24 TO 36 HOURS AS PRIMARY UPPER-LOW DEEPENS OVER WESTCENTRAL MINNESOTA AND SURFACE CYCLOGENESIS RAPIDLY COMMENCES OVER THE UPPER MIDWEST DURING THE DAY ON WEDNESDAY. CONSENSUS OF MODEL GUIDANCE TAKES DEEPENING SURFACE LOW SITUATED NEAR DVN BY 06Z WEDNESDAY...NORTHEAST TO NEAR GRB BY 15Z WEDNESDAY. DURING THIS PERIOD...HUGE SLUG OF DEEP MOISTURE OVER THE SOUTHERN AND CENTRAL MISSISSIPPI WILL ALSO BE RAPIDLY DRAWN NORTHWARD INTO WISCONSIN WEDNESDAY EVENING AS 850 MB SOUTHERLY WINDS INCREASE TO 30 TO 40 KTS. LEADING EDGE OF PRIMARY PRECIPITATION SHIELD SHOULD BEGIN TO IMPACT OUR SOUTHERN TIER OF COUNTIES AROUND 00Z WEDNESDAY...THEN STEADILY SPREAD NORTHWARD OVERNIGHT. INCREASING PRESSURE GRADIENT ON THE NORTH SIDE OF THE DEEPENING SURFACE LOW WILL ALSO LEAD TO INCREASING SOUTHEASTERLY BOUNDARY LAYER WINDS TUESDAY NIGHT INTO EARLY WEDNESDAY. STRONGEST QG FORCING AND DEEP LAYER LIFT EXPECTED TO MOVE ACROSS THE FORECAST AREA ROUGHLY BETWEEN ABOUT 06Z AND 15Z WEDNESDAY...WHEN THE BULK OF THE RAINFALL WILL OCCUR. FORTUNATELY THIS SYSTEM WILL BE RATHER PROGRESSIVE WITH THE BULK OF THE PRECIPITATION MOVING NORTHEAST OF THE FORECAST AREA BY AROUND 00Z THURSDAY AS MID-LEVEL DRY INTRUSION AND STRONG SUBSIDENCE PUSH ACROSS THE SOUTHERN HALF OF WISCONSIN. RAINFALL AMOUNTS ARE NOT EXPECTED TO BE EXCESSIVE...WITH STORM TOTAL PRECIPIATION AMOUNTS APPROACHING THREE QUARTER TO PERHAPS AN INCH LOCALLY OVER THE SOUTHWEST PORTION OF THE FORECAST AREA. LOOKS LIKE THE ENTIRE FORECAST AREA SHOULD SEE A DECENT SOAKING RAIN. .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY ISSUED AT 342 AM CDT TUE OCT 27 2015 SIGNIFICANT STORM EXPECTED TO MOVE ACROSS THE REGION WEDNESDAY AND THEN SLOWLY MOVE AWAY FROM THE REGION WEDNESDAY NIGHT AND THURSDAY. SOME SIGNIFICANT DIFFERENCES NOTED IN HOW MUCH COLD AIR GETS WRAPPED INTO THE SYSTEM ACROSS THE NORTH WEDNESDAY NIGHT WHICH WOULD HAVE AN IMPACT ON PRECIPITATION TYPES AND AMOUNT OF SNOW THE FAR NORTH WOULD RECEIVE. GFS IS SLOWER WITH COLDER AIR MOVING INTO THE NORTH...MAINLY LATE EVENING AND OVERNIGHT. THE ECMWF ON THE OTHER HAND WOULD SUGGEST SNOW WOULD START DURING THE EARLY EVENING HOURS AND CONTINUE INTO THURSDAY MORNING. 850MB WINDS WILL BECOME VERY FAVORABLE AT 340 DEGREES FOR LAKE ENHANCEMENT SNOW SHOWERS ACROSS THE NORTH IF THE COLDER AIR MATERIALIZES. LATER SHIFTS WILL NEED TO MONITOR THIS AND MAY NEED ADJUST SNOWFALL TOTALS ACCORDINGLY ONCE MODELS CONVERGE ] ON THE TIMING OF THE COLD AIR. FLURRIES MAY BE SEEN AS FAR SOUTH AS WISCONSIN RAPIDS TO THE FOX VALLEY LATE WEDNESDAY NIGHT BUT NO ACCUMULATION IS EXPECTED IN THIS REGION. GUSTY WESTERLY WINDS OF 30 TO 40 MPH CAN BE EXPECTED WEDNESDAY NIGHT INTO THURSDAY BEHIND THE DEPARTING SYSTEM. INCREASED RAIN CHANCES ACROSS THE AREA DUE TO COLD CYCLONIC FLOW AND WEAK DISTURBANCE MOVING ACROSS THE REGION. DO EXPECT INSTABILITY RAIN SHOWERS...WITH SNOW ACROSS THE NORTH DURING THE MORNING. THE SHOWERS WILL GRADUALLY DIMINISH DURING THE LATE AFTERNOON HOURS. THE NEXT CHANCE OF RAIN WILL OCCUR FRIDAY NIGHT AND SATURDAY AS A COLD FRONT MOVES ACROSS THE STATE. BEYOND THIS PERIOD...NO REAL SIGNIFICANT CHANCES FOR RAIN. MAIN STORY WILL BE THE ABOVE NORMAL TEMPERATURES EXPECTED THIS WEEKEND INTO EARLY NEXT WEEK. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1223 PM CDT TUE OCT 27 2015 AFTER A VFR AFTERNOON OVER THE REGION...ADVERSE FLYING WEATHER WILL QUICKLY OVERSPREAD NE WI THIS EVENING AS A STRENGHTHENING AREA OF LOW PRES MOVES NWD FROM THE MID-MS VALLEY TO THE WRN GREAT LAKES. ABUNDANT GULF MOISTURE WL BE AVAILABLE...THUS MODERATE TO HEAVY RAINFALL IS POSSIBLE DURING THE OVRNGT HOURS. CIGS/VSBYS ARE FCST TO DROP INTO THE MVFR RANGE WHEN THE PCPN BEGINS THIS EVENING AND THEN FALL INTO THE IFR RANGE OVRNGT AS THE RAIN INTENSIFIES. ALONG WITH THE PCPN...GUSTY EAST WINDS AROUND 20 KTS CAN BE EXPECTED FOR MOST OF TNGT. THE SFC LOW IS FCST TO LIFT NORTH AND CONT TO INTENSIFY ON WED...BRINGING ADDITIONAL RAINFALL AND A WIND SHIFT TO THE WEST. IFR CONDITIONS WL PERSIST WED MORNING AND MAY SLOWLY IMPROVE TO THE MVFR RANGE ONCE THE LOW BEGINS TO PULL AWAY IN THE AFTERNOON. THE WEST WINDS ARE ALSO EXPECTED TO GRADUALLY INCREASE WED AFTERNOON WITH GUSTS IN THE 25-30 KT RANGE. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....ESB LONG TERM......ECKBERG AVIATION.......AK
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1030 AM CDT TUE OCT 27 2015 .UPDATE... CURRENT REFLECTIVITY SHOWS LEADING SURGE OF PRECIPITATION MAKING ITS WAY THROUGH N IL PRESENTLY. THIS SURGE OF PRECIP IS ARRIVING SLIGHTLY LATER THAN PREVIOUS EXPECTED...SO REDUCED POPS UNTIL THE EARLY TO MID AFTERNOON ACROSS S WI. LATEST HRRR GUIDANCE SUPPORTS THIS THINKING. OTHERWISE...MID TO UPPER LEVEL CLOUD DECK OVER THE REGION WILL THICKEN THIS AFTERNOON INTO THE EVENING HOURS AS AREA OF LOW PRESSURE TRANSLATES FARTHER NORTH INTO THE REGION. RAIN CHANCES WILL INCREASE THIS AFTERNOON AND INTO THE EVENING...WITH THE BEST CHANCES BEING IN THE EVENING AND OVERNIGHT HOURS. EASTERLY WINDS WILL REMAIN GUSTY THIS AFTERNOON INTO THE EVENING. && .AVIATION/18Z TAFS/... VFR CIGS AND VSBYS WILL REDUCE TO MVFR THIS AFTERNOON AND IFR IN THE EVENING AS AN AREA OF LOW PRESSURE MAKES ITS WAY INTO THE REGION. A MOIST AIR MASS ASSOCIATED WITH THE LOW WILL PROVIDED ABUNDANT MOISTURE FOR MODERATE RAIN TO DEVELOP. THE BEST CHANCES WILL BE LATER THIS AFTERNOON...INTO THE EVENING AND OVERNIGHT. GUSTY EASTERLY WINDS IN THE LOWER TO MID 20 KT RANGE WILL DEVELOP THIS AFTERNOON AND LAST INTO THE EVENING HOURS. WIND-DRIVEN RAIN WILL AFFECT VSBYS LATER TONIGHT...LEADING TO THE REDUCTION TO MVFR AND IFR CONDITIONS. && .PREV DISCUSSION... /ISSUED 347 AM CDT TUE OCT 27 2015/ SHORT TERM... TODAY - CONFIDENCE...MEDIUM. PROTECTIVE MID-LEVEL RIDGING OVER SOUTHERN WI AND THE WESTERN GTLAKES MOVING OFF TO THE NORTHEAST...SUCCUMBING TO UPSTREAM PHASING OF NORTHERN AND SOUTHERN STREAM WAVES. THIS UPSTREAM TROF AMPLIFICATION WILL PULL LOW PRESSURE OVER THE SOUTHERN MS VALLEY REGION NORTHWARD TODAY AND TONIGHT. THIS NORTHWARD MOVING LOW PRESSURE SYSTEM HAS DEEPER COLUMN HUMIDITY ASSOCIATED WITH IT. PRECIPITABLE WATER IS EXPECTED TO MORE THAN DOUBLE IN THE NEXT 12-18 HOURS TO OVER 1 INCH. SFC DEWPOINTS IN THE LOWER 50S ARE NOW CREEPING NORTHWARD ACROSS IL AND THE CENTRAL MS VALLEY REGION. THIS SURGE OF MOISTURE WILL INITIALLY BE FIGHTING AGAINST A DRY EASTERLY AIR FEED ACROSS THE LOWER GTLAKES. HENCE THIS WILL SLOW THE DEVELOPMENT OF MEASUREABLE RAIN ACROSS SRN WI FOR A TIME TODAY INTO THIS EVENING ACROSS THE EASTERN CWA. NEVER THE LESS...WITH SURGE OF MOISTURE ALONG WARM CONVEYOR BELT THIS AFTERNOON...EXPECT AREAS OF LIGHT RAIN TO SPREAD INTO SOUTHWEST CWA IN THE EARLY AFTN...EVENTUALLY MAKING ITS WAY NORTH AND EAST THROUGH THE LATE AFTN INTO THE EARLY EVENING. LAYER Q-VECTOR CONVERGENCE INCREASES DURING THE AFTERNOON AND EARLY EVENING AS LOW LEVEL JET AND INCREASED LOW TO MID LEVEL CONVERGENCE INCREASE OVER THE WESTERN GTLAKES. TONIGHT - CONFIDENCE...HIGH. WIDESPREAD RAIN IS EXPECTED DURING THE EVENING AS SURGE OF MOISTURE TIED TO PASSING MID-LEVEL SHORT WAVE AND INCREASING LOW LEVEL CONVERGENCE PASS ACROSS SRN WI. QPF FROM THIS AFTN THRU TNGT SHOULD BE AROUND THREE QUARTER INCHES. MID-LEVEL DRYING WILL BEGIN TO WRAP AROUND THE DEEPENING LOW PRESSURE SYSTEM OVER THE TRI-STATE AREA LATE TONIGHT. THIS WILL LIKELY TRANSITION THE STEADY RAIN TO PERIODS OF LIGHT RAIN AND LIGHT SHOWERS. WEDNESDAY THROUGH THURSDAY... FORECAST CONFIDENCE MEDIUM. EXPECT LULLS IN THE PRECIP DURING THE DAY WED AS MID LEVELS BEGIN TO DRY OUT. LOW CLOUDS AND DRIZZLE ARE LIKELY FOR THE MORNING HOURS AS THE SURFACE LOW TRACKS OVERHEAD. HIGHS WED WILL BE LIMITED IN THE 50S WHICH WILL OCCUR DURING THE MORNING HOURS. THE CLOSED UPPER LOW WILL SLIDE SOUTHEAST THROUGH THE DAKOTAS AND MN ON WED. THIS WILL BRING THE COLDER AIR INTO SOUTHERN WI LATE WED AFTERNOON. THE STRONG COLD AIR ADVECTION WILL ALLOW FOR STEEP LOW LEVEL LAPSE RATES... A PERIOD OF ENHANCED SHOWER ACTIVITY AND VERY GUSTY WINDS. NW 850 MB WINDS WILL APPROACH 50 KNOTS OVER SOUTHERN WI IN THE WAKE OF THE UPPER LOW WED NIGHT. GUSTS TO 40 MPH SEEM LIKELY OVERNIGHT. SHOWERS COULD TAP INTO THE SNOW GROWTH ZONE LATER WED NIGHT INTO THU MORNING SO SNOW SHOWERS ARE POSSIBLE. THE GROUND WILL BE TOO WARM FOR ANY ACCUMULATION. BLUSTERY NORTHWEST WINDS WILL PERSIST THROUGH THE DAY THURSDAY... ALONG WITH A STRATOCUMULUS CLOUD DECK. SHOWERS SHOULD TAPER OFF BY EARLY AFTERNOON AS DRIER AIR WORKS INTO THE REGION. LONG TERM... FRIDAY THROUGH SUNDAY... FORECAST CONFIDENCE MEDIUM. TEMPERATURES SHOULD BOTTOM OUT AROUND FREEZING INLAND FROM LAKE MICHIGAN FRI MORNING WITH CLEARING SKIES AND DIMINISHING WINDS. A MID LEVEL TROUGH APPROACHING THE UPPER MIDWEST WILL DRAW SOUTHERLY WINDS AND MORE SEASONABLE TEMPERATURES BACK INTO THE AREA ON FRIDAY AND THE REST OF THE WEEKEND. MOISTURE WILL RETURN AS WELL... LEADING TO CHANCES FOR RAIN FRIDAY NIGHT THROUGH SATURDAY. MONDAY AND BEYOND... FORECAST CONFIDENCE LOW. MODELS ARE STRUGGLING WITH AN UPPER LOW OVER THE SOUTHWEST US... SO PRECIP CHANCES FOR EARLY NEXT WEEK REMAIN UNCERTAIN. AVIATION/12Z TAFS/... VFR CONDITIONS TODAY WILL YIELD TO RAPIDLY FALLING CIGS AND VSBYS FROM MID AFTN THRU THE EVENING AS WIDESPREAD RAIN OVERSPREADS TAF SITES. WITH MOIST ELY FLOW AND STRONG WINDS...EXPECT CIGS TO FALL TO IFR AND POSSIBLY BELOW ALTERNATE MINIMUMS DURING THE EVENING...WITH LITTLE RECOVERY EXPECTED THROUGH THE LATE NIGHT. BLUSTERY ELY WINDS WILL ACCOMPANY OVERNIGHT RAIN. SOME IMPROVEMENT IN CIGS LIKELY LATER WED AS STEADY PRECIP TURNS MORE SHOWERY. MARINE...NORTHWARD MOVING LOW PRESSURE IS EXPECTED TO UNDERGO RAPID DEEPENING OVER THE WESTERN GREAT LAKES ON WEDNESDAY AS IT TRACKS NORTHWARD FROM THE LAKE MICHIGAN VICINITY TO LAKE SUPERIOR. A TIGHT PRESSURE GRADIENT ON THE SOUTH SIDE OF THE LOW AND STRONG COLD ADVECTION OVER THE RELATIVELY WARMER LAKE MICHIGAN WATERS WILL ALLOW STRONG GUSTY WINDS TO AFFECT THE LAKE SURFACE FROM WED AFTN INTO THU. STRENGTH OF LOW LEVEL FLOW ASSOCIATED WITH LOW PRESSURE WILL CREATE FAVORABLE CONDITIONS FOR WIND GUSTS REACHING 35 KTS. HENCE WL UPGRADE ONGOING SMALL CRAFT ADVISORY TO GALE WATCH FOR THE PERIOD FROM 21Z/WED TO 21Z/THU. WILL ALSO PUSH UP START TIME OF ONGOING SMALL CRAFT ADVISORY SEVERAL HOURS TO 15Z. WILMETTE BUOY REPORTING 4-5FT WAVES AT 08Z WITH 19KT ONSHORE WIND GUSTS. EXPECT WIND GUSTS TO 20KTS TO DEVELOP BY MID- MORNING ACROSS THE NEARSHORE WATERS. THE LOW PRESSURE SYSTEM OVER THE SOUTHERN MS VALLEY REGION WILL MOVE TOWARD WI TODAY AND TONIGHT RESULTING IN THE INCREASING ELY SFC WINDS. A FEW GUSTS COULD GET CLOSE TO GALE CRITERIA TONIGHT BEFORE THE PRESSURE GRADIENT WEAKENS DUE TO THE PROXIMITY OF THE PASSING LOW PRESSURE SYSTEM. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON FOR LMZ643>646. SMALL CRAFT ADVISORY UNTIL 4 PM CDT WEDNESDAY FOR LMZ643>646. && $$ UPDATE...JTS TODAY/TONIGHT AND AVIATION/MARINE...MBK WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
651 AM CDT TUE OCT 27 2015 UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY ISSUED AT 342 AM CDT TUE OCT 27 2015 FOCUS IN THE SHORT TERM WILL CONTINUE TO BE ON THE TIMING AND DURATION OF STRATIFORM RAIN SHIELD FORECAST TO EVOLVE OVER THE FORECAST AREA...AS NORTHERN AND SOUTHERN STREAM ENERGY CONGEAL OVER THE UPPER MIDWEST AND GREAT LAKES REGION TONIGHT AND WEDNESDAY. IN THE MEANTIME...WEAK MID-LEVEL FRONTOGENETIC FORCING IN CONCERT WITH SUBTLE SHORTWAVE IMPULSES AND SOMEWHAT DEEPER MOISTURE CONTINUES TO GENERATE A PESKY NARROW BAND OF VERY LIGHT RAIN OR SPRINKLES CURRENTLY EXTENDING FROM NORTHCENTRAL WISCONSIN TO NORTHERN MINNESOTA. RAP SEEMS TO HAVE CAPTURED THE BASIC EVOLUTION OF THIS VERY LIGHT PRECIPITATION BAND AND CARRIES IT NORTHWARD INTO UPPER MICHIGAN BY 14 OR 15Z THIS MORNING WHICH SEEMS REASONABLE BASED ON CURRENT TRENDS. NOT GOING TO INCLUDE MENTION OF ANY POPS THIS MORNING FOR THE FAR NORTH AS MEASURABLE AMOUNTS ARE DUBIOUS AT THIS POINT. OTHERWISE...FOR THE REMAINDER OF TODAY EXPECT LOTS OF MID-LEVEL CLOUDINESS WITHIN BROAD AREA OF WEAK ISENTROPIC LIFT. ACROSS NORTHERN WISCONSIN...EXPECT MORE IN THE WAY OF LOW CLOUDS AND SOME PATCHY FOG FOR AT LEAST A COUPLE MORE HOURS EARLY THIS MORNING. DESPITE LOTS OF CLOUDS...TEMPERATURES WILL REMAIN WELL ABOVE NORMAL FOR LATE OCTOBER WITH READINGS MAINLY IN THE 55 TO 60 DEGREE RANGE. THEN FOCUS SHIFTS TO THIS EVENING AND OVERNIGHT...AS SHORTWAVE ENERGY OVER THE CENTRAL PLAINS GRADUALLY CONGEALS WITH MORE POTENT SHORTWAVE DROPPING OUT OF CANADA. SOMEWHAT SURPRISINGLY...SEEMS TO BE FAIRLY DECENT CONSENSUS AMONG THE MODEL GUIDANCE ON THE OVERALL EVOLUTION OF THIS SYSTEM OVER THE NEXT 24 TO 36 HOURS AS PRIMARY UPPER-LOW DEEPENS OVER WESTCENTRAL MINNESOTA AND SURFACE CYCLOGENESIS RAPIDLY COMMENCES OVER THE UPPER MIDWEST DURING THE DAY ON WEDNESDAY. CONSENSUS OF MODEL GUIDANCE TAKES DEEPENING SURFACE LOW SITUATED NEAR DVN BY 06Z WEDNESDAY...NORTHEAST TO NEAR GRB BY 15Z WEDNESDAY. DURING THIS PERIOD...HUGE SLUG OF DEEP MOISTURE OVER THE SOUTHERN AND CENTRAL MISSISSIPPI WILL ALSO BE RAPIDLY DRAWN NORTHWARD INTO WISCONSIN WEDNESDAY EVENING AS 850 MB SOUTHERLY WINDS INCREASE TO 30 TO 40 KTS. LEADING EDGE OF PRIMARY PRECIPITATION SHIELD SHOULD BEGIN TO IMPACT OUR SOUTHERN TIER OF COUNTIES AROUND 00Z WEDNESDAY...THEN STEADILY SPREAD NORTHWARD OVERNIGHT. INCREASING PRESSURE GRADIENT ON THE NORTH SIDE OF THE DEEPENING SURFACE LOW WILL ALSO LEAD TO INCREASING SOUTHEASTERLY BOUNDARY LAYER WINDS TUESDAY NIGHT INTO EARLY WEDNESDAY. STRONGEST QG FORCING AND DEEP LAYER LIFT EXPECTED TO MOVE ACROSS THE FORECAST AREA ROUGHLY BETWEEN ABOUT 06Z AND 15Z WEDNESDAY...WHEN THE BULK OF THE RAINFALL WILL OCCUR. FORTUNATELY THIS SYSTEM WILL BE RATHER PROGRESSIVE WITH THE BULK OF THE PRECIPITATION MOVING NORTHEAST OF THE FORECAST AREA BY AROUND 00Z THURSDAY AS MID-LEVEL DRY INTRUSION AND STRONG SUBSIDENCE PUSH ACROSS THE SOUTHERN HALF OF WISCONSIN. RAINFALL AMOUNTS ARE NOT EXPECTED TO BE EXCESSIVE...WITH STORM TOTAL PRECIPIATION AMOUNTS APPROACHING THREE QUARTER TO PERHAPS AN INCH LOCALLY OVER THE SOUTHWEST PORTION OF THE FORECAST AREA. LOOKS LIKE THE ENTIRE FORECAST AREA SHOULD SEE A DECENT SOAKING RAIN. .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY ISSUED AT 342 AM CDT TUE OCT 27 2015 SIGNIFICANT STORM EXPECTED TO MOVE ACROSS THE REGION WEDNESDAY AND THEN SLOWLY MOVE AWAY FROM THE REGION WEDNESDAY NIGHT AND THURSDAY. SOME SIGNIFICANT DIFFERENCES NOTED IN HOW MUCH COLD AIR GETS WRAPPED INTO THE SYSTEM ACROSS THE NORTH WEDNESDAY NIGHT WHICH WOULD HAVE AN IMPACT ON PRECIPITATION TYPES AND AMOUNT OF SNOW THE FAR NORTH WOULD RECEIVE. GFS IS SLOWER WITH COLDER AIR MOVING INTO THE NORTH...MAINLY LATE EVENING AND OVERNIGHT. THE ECMWF ON THE OTHER HAND WOULD SUGGEST SNOW WOULD START DURING THE EARLY EVENING HOURS AND CONTINUE INTO THURSDAY MORNING. 850MB WINDS WILL BECOME VERY FAVORABLE AT 340 DEGREES FOR LAKE ENHANCEMENT SNOW SHOWERS ACROSS THE NORTH IF THE COLDER AIR MATERIALIZES. LATER SHIFTS WILL NEED TO MONITOR THIS AND MAY NEED ADJUST SNOWFALL TOTALS ACCORDINGLY ONCE MODELS CONVERGE ] ON THE TIMING OF THE COLD AIR. FLURRIES MAY BE SEEN AS FAR SOUTH AS WISCONSIN RAPIDS TO THE FOX VALLEY LATE WEDNESDAY NIGHT BUT NO ACCUMULATION IS EXPECTED IN THIS REGION. GUSTY WESTERLY WINDS OF 30 TO 40 MPH CAN BE EXPECTED WEDNESDAY NIGHT INTO THURSDAY BEHIND THE DEPARTING SYSTEM. INCREASED RAIN CHANCES ACROSS THE AREA DUE TO COLD CYCLONIC FLOW AND WEAK DISTURBANCE MOVING ACROSS THE REGION. DO EXPECT INSTABILITY RAIN SHOWERS...WITH SNOW ACROSS THE NORTH DURING THE MORNING. THE SHOWERS WILL GRADUALLY DIMINISH DURING THE LATE AFTERNOON HOURS. THE NEXT CHANCE OF RAIN WILL OCCUR FRIDAY NIGHT AND SATURDAY AS A COLD FRONT MOVES ACROSS THE STATE. BEYOND THIS PERIOD...NO REAL SIGNIFICANT CHANCES FOR RAIN. MAIN STORY WILL BE THE ABOVE NORMAL TEMPERATURES EXPECTED THIS WEEKEND INTO EARLY NEXT WEEK. && .AVIATION...FOR 12Z TAF ISSUANCE ISSUED AT 649 AM CDT TUE OCT 27 2015 OTHER THAN SOME SCT IFR CIGS OVER NORTHERN WISCONSIN UNTIL ABOUT 14Z...MAINLY VFR CONDITIONS WILL PREVAIL THROUGH EARLY THIS EVENING. A COMPLEX WEATHER SYSTEM WILL THEN RAPIDLY CONGEAL OVER THE UPPER MIDWEST OVERNIGHT TONIGHT...WITH A LARGE AREA OF STRATIFORM RAINFALL FORECAST TO SPREAD FROM SOUTH TO NORTH ACROSS THE FORECAST AREA LATE THIS EVENING. VFR CONDITIONS WILL GRADUALLY GIVE WAY TO MVFR CIGS AND VSBYS AS RAINFALL COMMENCES...FIRST AT WESTERN TAFS SITES INCLUDING AUW/CWA AFTER ABOUT 03Z...THEN EASTCENTRAL TAF SITES INCLUDING ATW/GRB AFTER ABOUT 06Z. MVFR CONDITIONS WILL LIKELY NOT REACH THE NORTHERN PORTION OF THE FORECAST AREA UNTIL AFTER 09Z. CONDITIONS WILL LIKELY CONTINUE TO DETERIORATE TO IFR OVER AT LEAST THE SOUTHERN THIRD OF THE FORECAST AREA AFTER 09Z WEDNESDAY IN LIGHT TO MODERATE RAIN. BRISK SOUTHEAST WINDS WILL ALSO DEVELOP LATER THIS EVENING...WITH OCCASIONAL GUSTS TO 20 KTS...AS A DEEPENING LOW PRESSURE SYSTEM APPROACHES FROM EASTERN IOWA. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....ESB LONG TERM......ECKBERG AVIATION.......ESB
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY ISSUED AT 342 AM CDT TUE OCT 27 2015 FOCUS IN THE SHORT TERM WILL CONTINUE TO BE ON THE TIMING AND DURATION OF STRATIFORM RAIN SHIELD FORECAST TO EVOLVE OVER THE FORECAST AREA...AS NORTHERN AND SOUTHERN STREAM ENERGY CONGEAL OVER THE UPPER MIDWEST AND GREAT LAKES REGION TONIGHT AND WEDNESDAY. IN THE MEANTIME...WEAK MID-LEVEL FRONTOGENETIC FORCING IN CONCERT WITH SUBTLE SHORTWAVE IMPULSES AND SOMEWHAT DEEPER MOISTURE CONTINUES TO GENERATE A PESKY NARROW BAND OF VERY LIGHT RAIN OR SPRINKLES CURRENTLY EXTENDING FROM NORTHCENTRAL WISCONSIN TO NORTHERN MINNESOTA. RAP SEEMS TO HAVE CAPTURED THE BASIC EVOLUTION OF THIS VERY LIGHT PRECIPITATION BAND AND CARRIES IT NORTHWARD INTO UPPER MICHIGAN BY 14 OR 15Z THIS MORNING WHICH SEEMS REASONABLE BASED ON CURRENT TRENDS. NOT GOING TO INCLUDE MENTION OF ANY POPS THIS MORNING FOR THE FAR NORTH AS MEASURABLE AMOUNTS ARE DUBIOUS AT THIS POINT. OTHERWISE...FOR THE REMAINDER OF TODAY EXPECT LOTS OF MID-LEVEL CLOUDINESS WITHIN BROAD AREA OF WEAK ISENTROPIC LIFT. ACROSS NORTHERN WISCONSIN...EXPECT MORE IN THE WAY OF LOW CLOUDS AND SOME PATCHY FOG FOR AT LEAST A COUPLE MORE HOURS EARLY THIS MORNING. DESPITE LOTS OF CLOUDS...TEMPERATURES WILL REMAIN WELL ABOVE NORMAL FOR LATE OCTOBER WITH READINGS MAINLY IN THE 55 TO 60 DEGREE RANGE. THEN FOCUS SHIFTS TO THIS EVENING AND OVERNIGHT...AS SHORTWAVE ENERGY OVER THE CENTRAL PLAINS GRADUALLY CONGEALS WITH MORE POTENT SHORTWAVE DROPPING OUT OF CANADA. SOMEWHAT SURPRISINGLY...SEEMS TO BE FAIRLY DECENT CONSENSUS AMONG THE MODEL GUIDANCE ON THE OVERALL EVOLUTION OF THIS SYSTEM OVER THE NEXT 24 TO 36 HOURS AS PRIMARY UPPER-LOW DEEPENS OVER WESTCENTRAL MINNESOTA AND SURFACE CYCLOGENESIS RAPIDLY COMMENCES OVER THE UPPER MIDWEST DURING THE DAY ON WEDNESDAY. CONSENSUS OF MODEL GUIDANCE TAKES DEEPENING SURFACE LOW SITUATED NEAR DVN BY 06Z WEDNESDAY...NORTHEAST TO NEAR GRB BY 15Z WEDNESDAY. DURING THIS PERIOD...HUGE SLUG OF DEEP MOISTURE OVER THE SOUTHERN AND CENTRAL MISSISSIPPI WILL ALSO BE RAPIDLY DRAWN NORTHWARD INTO WISCONSIN WEDNESDAY EVENING AS 850 MB SOUTHERLY WINDS INCREASE TO 30 TO 40 KTS. LEADING EDGE OF PRIMARY PRECIPITATION SHIELD SHOULD BEGIN TO IMPACT OUR SOUTHERN TIER OF COUNTIES AROUND 00Z WEDNESDAY...THEN STEADILY SPREAD NORTHWARD OVERNIGHT. INCREASING PRESSURE GRADIENT ON THE NORTH SIDE OF THE DEEPENING SURFACE LOW WILL ALSO LEAD TO INCREASING SOUTHEASTERLY BOUNDARY LAYER WINDS TUESDAY NIGHT INTO EARLY WEDNESDAY. STRONGEST QG FORCING AND DEEP LAYER LIFT EXPECTED TO MOVE ACROSS THE FORECAST AREA ROUGHLY BETWEEN ABOUT 06Z AND 15Z WEDNESDAY...WHEN THE BULK OF THE RAINFALL WILL OCCUR. FORTUNATELY THIS SYSTEM WILL BE RATHER PROGRESSIVE WITH THE BULK OF THE PRECIPITATION MOVING NORTHEAST OF THE FORECAST AREA BY AROUND 00Z THURSDAY AS MID-LEVEL DRY INTRUSION AND STRONG SUBSIDENCE PUSH ACROSS THE SOUTHERN HALF OF WISCONSIN. RAINFALL AMOUNTS ARE NOT EXPECTED TO BE EXCESSIVE...WITH STORM TOTAL PRECIPIATION AMOUNTS APPROACHING THREE QUARTER TO PERHAPS AN INCH LOCALLY OVER THE SOUTHWEST PORTION OF THE FORECAST AREA. LOOKS LIKE THE ENTIRE FORECAST AREA SHOULD SEE A DECENT SOAKING RAIN. .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY ISSUED AT 342 AM CDT TUE OCT 27 2015 SIGNIFICANT STORM EXPECTED TO MOVE ACROSS THE REGION WEDNESDAY AND THEN SLOWLY MOVE AWAY FROM THE REGION WEDNESDAY NIGHT AND THURSDAY. SOME SIGNIFICANT DIFFERENCES NOTED IN HOW MUCH COLD AIR GETS WRAPPED INTO THE SYSTEM ACROSS THE NORTH WEDNESDAY NIGHT WHICH WOULD HAVE AN IMPACT ON PRECIPITATION TYPES AND AMOUNT OF SNOW THE FAR NORTH WOULD RECEIVE. GFS IS SLOWER WITH COLDER AIR MOVING INTO THE NORTH...MAINLY LATE EVENING AND OVERNIGHT. THE ECMWF ON THE OTHER HAND WOULD SUGGEST SNOW WOULD START DURING THE EARLY EVENING HOURS AND CONTINUE INTO THURSDAY MORNING. 850MB WINDS WILL BECOME VERY FAVORABLE AT 340 DEGREES FOR LAKE ENHANCEMENT SNOW SHOWERS ACROSS THE NORTH IF THE COLDER AIR MATERIALIZES. LATER SHIFTS WILL NEED TO MONITOR THIS AND MAY NEED ADJUST SNOWFALL TOTALS ACCORDINGLY ONCE MODELS CONVERGE ] ON THE TIMING OF THE COLD AIR. FLURRIES MAY BE SEEN AS FAR SOUTH AS WISCONSIN RAPIDS TO THE FOX VALLEY LATE WEDNESDAY NIGHT BUT NO ACCUMULATION IS EXPECTED IN THIS REGION. GUSTY WESTERLY WINDS OF 30 TO 40 MPH CAN BE EXPECTED WEDNESDAY NIGHT INTO THURSDAY BEHIND THE DEPARTING SYSTEM. INCREASED RAIN CHANCES ACROSS THE AREA DUE TO COLD CYCLONIC FLOW AND WEAK DISTURBANCE MOVING ACROSS THE REGION. DO EXPECT INSTABILITY RAIN SHOWERS...WITH SNOW ACROSS THE NORTH DURING THE MORNING. THE SHOWERS WILL GRADUALLY DIMINISH DURING THE LATE AFTERNOON HOURS. THE NEXT CHANCE OF RAIN WILL OCCUR FRIDAY NIGHT AND SATURDAY AS A COLD FRONT MOVES ACROSS THE STATE. BEYOND THIS PERIOD...NO REAL SIGNIFICANT CHANCES FOR RAIN. MAIN STORY WILL BE THE ABOVE NORMAL TEMPERATURES EXPECTED THIS WEEKEND INTO EARLY NEXT WEEK. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1047 PM CDT MON OCT 26 2015 DESPITE RAIN ENDING AND A SHORTWAVE PULLING OUT OF THE REGION...LIFR CONDITIONS CONTINUE AT THE RHI SITE. GIVEN THE LACK OF A STRONG PUSH OF DRY AIR AT THE LOWER LEVELS WILL KEEP LIFR CONDITIONS IN THROUGH TUESDAY MORNING WHEN WINDS PICK UP AHEAD OF THE NEXT LOW PRESSURE SYSTEM APPROACHING FROM THE WEST. AT THE REST OF THE TAF SITES...MID CLOUDS WILL CONTINUE WITH SOME PATCHY MVFR FOG EXPECTED LATE TONIGHT AND INTO TUESDAY MORNING. RAIN FROM THE NEXT SYSTEM WILL SPREAD INTO THE AREA FROM SOUTH TO NORTH...WITH THE SOUTHERN TAF SITES LIKELY SEEING RAIN TUESDAY EVENING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....ESB LONG TERM......ECKBERG AVIATION.......KURIMSKI
AREA FORECAST DISCUSSION
NWS JACKSON KY
159 AM EDT THU OCT 29 2015 .UPDATE... ISSUED AT 1114 PM EDT WED OCT 28 2015 SHOWERS HAVE EXPANDED INTO A BROKEN LINE ACROSS NORTHERN KENTUCKY. THE LATEST HRRR HAS THIS MOVING THROUGH OUR AREA BETWEEN 05 AND 10Z. HAVE ADJUSTED THE POPS TOWARDS THIS SOLUTION SINCE IT HAS INITIALIZED FAIRLY WELL WITH THE CURRENT RADAR TRENDS. AS SUCH...WENT UP TO LIKELY POPS GENERALLY NEAR AND NORTH OF THE MOUNTAIN PARKWAY OVERNIGHT...WITH LESSER POPS TO THE SOUTHWEST. THIS BAND SHOULD GRADUALLY DIMINISH AS IT DROPS SOUTHEAST ACROSS OUR AREA. SOME OF THE VALLEYS HAVE ACTUALLY DECOUPLED THANKS TO PARTIALLY CLEARING SKIES OVERHEAD. THIS SHOULD BE TEMPORARY AS ADDITIONAL CLOUD COVER IS ALREADY STARTING TO FILL BACK IN UPSTREAM. DID UP THE LOWS A TOUCH BASED ON THE LATEST TRENDS IN OBSERVATIONS. UPDATE ISSUED AT 853 PM EDT WED OCT 28 2015 SHOWERS HAVE WANED IN AREAL COVERAGE ACROSS EASTERN KENTUCKY THIS EVENING...AS THE DRY SLOT HAS MOVED IN. MORE SHOWER ACTIVITY HAS POPPED UP FURTHER TO OUR NORTHWEST ASSOCIATED WITH THE SURFACE FRONT AND A MID-LEVEL SHORT WAVE TROUGH ROTATING THROUGH THE OHIO VALLEY. THIS WILL BE MOVING IN OVERNIGHT...WITH AN EXPECTED UPTICK IN ACTIVITY. HAVE UPDATED TO REMOVE THE MENTION OF THUNDER AS SCHEDULED...GIVEN THE DIMINISHMENT OF INSTABILITY. ALSO ALIGNED THE HOURLY TEMPERATURES AND DEW POINTS WITH THE CURRENT OBSERVATIONS TO ACCOUNT FOR THE SLOWER DROP OFF THROUGH THE EVENING HOURS. WILL TAKE A LOOK AT LOW TEMPERATURES A BIT LATER THIS EVENING. UPDATES HAVE BEEN SENT. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 257 PM EDT WED OCT 28 2015 SEVERAL BROKEN LINES/BANDS OF SHOWERS HAVE DEVELOPED ACROSS THE REGION THIS AFTERNOON. SEEING A FEW EMBEDDED ENHANCED ECHOES AS WELL. DECIDED TO KEEP MENTION OF ISOLD THUNDER UNTIL EARLY THIS EVENING WITH LOSE OF DAYTIME HEATING. EXPECT SHOWER ACTIVITY TO DIMINISH AGAIN WITH SUNSET. HOWEVER...FRONTAL BOUNDARY WILL PUSH INTO THE AREA LATE TONIGHT AND WITH IT WILL THE THREAT OF SHOWERS WILL RETURN. SEEING SOME SUPPORT FOR THIS LINE OF THINKING FROM THE HRRR AS WELL. BOUNDARY PUSHES OFF TO OUR EAST TOMORROW MORNING WHICH WILL USHER IN SOME DRYING AND FAIR WEATHER AS HIGH PRESSURE BEGINS TO BUILD INTO OHIO VALLEY. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 257 PM EDT WED OCT 28 2015 AT UPPER LEVELS...THE PERIOD BEGINS WITH SHORTWAVE RIDGING PUSHING OFF TO THE EAST SATURDAY BEFORE LOWER HEIGHTS AND SHORTWAVE TROUGHING MOVE IN FROM THE WEST. THE GFS AND ECMWF HAVE COME INTO BETTER AGREEMENT REGARDING THIS SYSTEM...BUT IT APPEARS THAT THE GFS IS STILL A BIT FASTER AND MORE PROGRESSIVE WITH THE SYSTEMS EXIT MONDAY NIGHT. RIDGING THEN BUILDS BACK INTO THE AREA BY THE END OF THE PERIOD. AT THE SURFACE...FRIDAY INTO SATURDAY MORNING SHOULD REMAIN COOL AND DRY WITH HIGH PRESSURE OVERHEAD. AS A SFC LOW MOVES NEWD FROM TX TOWARDS THE TENNESSEE VALLEY SATURDAY...MOISTURE AND CLOUD COVER WILL BUILD INTO THE REGION. RAIN CHANCES INCREASE BY SATURDAY EVENING AND CONTINUE THROUGH EARLY TUESDAY. AS OF RIGHT NOW...LOOKS LIKE THE MAJORITY OF THE RAIN WILL HOLD OFF UNTIL LATE SATURDAY NIGHT...WHICH LOOKS FAVORABLE FOR ANY OUTDOOR ACTIVITIES ON HALLOWEEN. RAIN WILL HANG AROUND THE AREA LATE SATURDAY THROUGH EARLY TUESDAY MORNING...WITH SOME SHOWERS LINGERING THROUGHOUT THE DAY TUESDAY BEFORE THE WEATHER DRIES OUT ON WEDNESDAY. TEMPERATURES WILL START OUT ON THE COOL SIDE FRIDAY BUT THEN BE SEASONABLE THROUGH SUNDAY. AFTERNOON HIGHS WILL THEN WARM INTO THE LOWER 70S MONDAY THROUGH WEDNESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 159 AM EDT THU OCT 29 2015 A COLD FRONT WILL MOVE SOUTHEAST THROUGH THE REGION OVERNIGHT TONIGHT. IT WILL BE ACCOMPANIED BY AT LEAST SCATTERED SHOWERS AND PROBABLY A BRIEF PERIOD OF MVFR CEILINGS. THE SUB-VFR CONDITIONS ARE EXPECTED TO EXIT TO THE SOUTHEAST INTO VA BY AROUND 14Z...LEAVING US WITH VFR FOR THE REMAINDER OF THE PERIOD. WINDS WILL PICK UP FROM THE WEST DURING THE DAY ON THURSDAY...WITH GUSTS OF 15-20 KTS. WINDS WILL SUBSIDE ON THURSDAY EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEOGERIAN SHORT TERM...RAY LONG TERM...JVM AVIATION...HAL
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
147 AM EDT THU OCT 29 2015 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 325 PM EDT WED OCT 28 2015 WET AND WINDY WEATHER WILL CONTINUE OVER THE NEXT 24 HOURS. THE WINDS COULD GUST AS HIGH AS 40 MPH TONIGHT INTO THURSDAY MORNING AS THE RAIN SHOWERS REMAIN PERSISTENT. A FEW LAKE EFFECT SHOWERS MAY CONTINUE NEAR THE LAKESHORE THURSDAY NIGHT...ELSEWHERE IT WILL DRY OUT...WITH THE WIND DIMINISHING. AFTER A DRY FRIDAY THE NEXT CHANCE OF RAIN ARRIVES LATE FRIDAY NIGHT INTO SATURDAY. THE AREA SHOULD DRY OUT AGAIN BY SUNDAY...BUT ANOTHER CHANCE OF LIGHT RAIN SHOULD RETURN BY TUESDAY. AFTER A COOL PERIOD THURSDAY THROUGH SATURDAY...WE SHOULD WARM TO 60 TO 65 FOR THE FIRST PART OF NEXT WEEK. && .UPDATE... ISSUED AT 1013 PM EDT WED OCT 28 2015 DID A QUICK UPDATE THIS EVENING TO TOUCH UP WIND GUSTS AND CHANCES FOR PRECIPITATION. THE COLD FRONT STRETCHES NORTH/SOUTH ALONG HIGHWAY 131...PLOWING OFF TO THE EAST FAIRLY RAPIDLY. WIND GUSTS OF 40+ MPH HAVE OCCURRED WITH THE INITIAL LINE OF SHOWERS LOCATED ALONG THE FRONT. IT WILL REMAIN WINDY THROUGH THE NIGHT AS A TIGHT PRESSURE GRADIENT WILL NOW REMAIN IN PLACE RIGHT INTO THURSDAY MIDDAY. 15 TO 30 MPH WILL BE COMMON FOR SUSTAINED WINDS INTO THURSDAY AFTERNOON WITH 30 TO 40 MPH GUSTS. A FEW POWER OUTAGES HAVE SHOWN UP ON THE CONSUMERS PAGE ALONG THE LAKESHORE AND WILL NOT BE SURPRISED TO SEE A FEW MORE AS GUSTS OF THIS MAGNITUDE BRING DOWN DEAD LIMBS ONTO POWER LINES. AS FOR THE PRECIP HAVE 80+ PCT POPS ALONG THE LAKESHORE AS LAKE EFFECT PRECIP GENERATION WILL ROLL INTO FULL SWING. DELTA T/S BY MORNING WILL BE AROUND 18C WITH A LAKE TEMP OF 13C AND 850MB TEMPS AROUND -5C. HAVE OPTED TO THROW IN THE MENTION OF RAIN AND SNOW SHOWERS IN INTERIOR CENTRAL LOWER MICHIGAN AT -5C SHOULD BE COLD ENOUGH AND THE HRRR PRECIP TYPE AGREES. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 325 PM EDT WED OCT 28 2015 RAIN SHOWERS WILL CONTINUE TONIGHT INTO THURSDAY MORNING...THEN GRADUALLY DIMINISH. WINDS WILL BE QUITE STRONG ON THE BACK SIDE OF THE SYSTEM TONIGHT INTO THE FIRST HALF OF THURSDAY. THE UPPER LOW WILL SWING THROUGH THE REGION LATE TONIGHT. A STRONG VORT COMES IN WITH IT SUPPLYING LIFT...SO THE PCPN COVERAGE SHOULD ONLY INCREASE OVERNIGHT INTO EARLY THURSDAY MORNING. ALONG WITH THE SYNOPTIC FEATURE...WE WILL ALSO SEE H8 TEMPS PLUNGE OVERNIGHT. THIS WILL HELP PRODUCE LAKE ENHANCED SHOWERS...ESPECIALLY AFTER MIDNIGHT. BOTTOM LINE...WE WILL STAY WET. THE SHOWERS WILL DIMINISH THROUGH THURSDAY AFTERNOON AS THE LOW DRIFTS AWAY AND THE DEEPER MOISTURE EXITS. IT WILL BE A CHILLY AND RAW THURSDAY. HIGHS WILL ONLY BE 45 TO 50 WITH A STRONG WIND. BORDERLINE WIND ADVISORY CONDITIONS FOR THE LAKESHORE...BUT WILL NOT ISSUE ONE AT THIS POINT AND STILL HIGHLIGHT 40 MPH GUSTS...AND 35 MPH INLAND. THE HIGHER WINDS KICK IN TONIGHT AND CONTINUE THURSDAY MORNING...BEFORE DIMINISHING THURSDAY AFTERNOON/EVENING. ANTICYCLONIC FLOW MOVES IN LATE THURSDAY NIGHT WHEN THE LAKE EFFECT WILL FINALLY END. SOME CLEARING...ESPECIALLY INLAND...WILL RESULT IN 30S FOR LOWS. DRY FOR FRIDAY WITH SURFACE HIGH PRESSURE MOVING ACROSS THE OHIO VALLEY. SOUTHERLY FLOW FRIDAY NIGHT WILL BRING A QUICK RETURN OF GULF MOISTURE. MUCH OF THE AREA SHOULD REMAIN DRY FRIDAY NIGHT...BUT SOME RAIN SHOWERS COULD RETURN OVER THE NW CWA LATE. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 325 PM EDT WED OCT 28 2015 THE MID LEVEL LOW DEVELOPING OVER THE SOUTHWEST U.S. IS FORECASTED TO OPEN UP AS IS TRACKS EASTWARD THROUGH THE ROCKIES. SOME OF IT/S ENERGY LIFTS NORTHEAST TOWARD THE GREAT LAKES REGION ON SATURDAY. A LOW LEVEL JET STRENGTHENS OVER THE PLAINS ON SATURDAY AS A RESULT OF THIS APPROACHING SYSTEM ON FRIDAY. THIS FEATURE WILL HELP TO ADVECT IN AN UNSEASONABLY MOIST AIR MASS INTO LOWER MICHIGAN AHEAD OF THE MID LEVEL WAVE. SHOWERS ARE EXPECTED TO ARRIVE SATURDAY... ESPECIALLY IN THE AFTERNOON FROM THE SOUTHWEST. THESE SHOWERS WILL THEN LINGER INTO SATURDAY NIGHT. I LEFT THUNDER OUT OF THE FORECAST DESPITE SOME INSTABILITY NEARING THE MI/IN BORDER SATURDAY AFTERNOON. IT SHOULD BE WINDY SATURDAY INTO SATURDAY NIGHT AS THE LOW LEVEL JET MOVES IN. THE MID LEVEL FLOW TURNS ZONAL BEHIND THIS DEPARTING WAVE. THIS MEANS A WARM UP FOR THE GREAT LAKES REGION. THE MONDAY THROUGH WEDNESDAY PERIOD SHOULD END UP WITH WELL ABOVE NORMAL TEMPERATURES. THERE COULD BE SOME CLOUDS AROUND...WHICH MAY OFFSET THE DAILY MAX TEMPERATURES. THUS I KEPT VALUES IN THE 60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 147 AM EDT THU OCT 29 2015 CONDITIONS HAVE IMPROVED OVER THE ENTIRE AREA OVER THE LAST COUPLE OF HOURS. THIS IS IN THE WAKE OF THE COLD FRONT THAT MOVED THROUGH EARLIER. A FEW SHOWERS ARE NOW REDEVELOPING WITH THE COLDER AIR COMING IN OVER THE LAKE. WE EXPECT TO SEE AN AREA OF MVFR CIGS OVER CENTRAL AND NRN WISCONSIN ROTATE IN ACROSS THE NRN TERMINALS ALONG WITH SOME BETTER SHOWER COVERAGE AFTER 12Z. THIS WILL LIKELY LAST MOST OF THE DAY...BEFORE THE LOWER CONDITIONS BEGIN TO LIFT OUT TO THE NE. THIS WILL ALLOW FOR VFR CONDITIONS TO SETTLE IN AFTER 21-22Z. WINDS WILL BE GUSTY FROM THE W/SW TODAY WITH GUSTS TO 30 KNOTS LIKELY. THESE WILL TAIL OFF LATER THIS AFTERNOON INTO THIS EVENING. && .MARINE... ISSUED AT 1013 PM EDT WED OCT 28 2015 ENDED THE SMALL CRAFT ADVISORY WITH THE GALE WARNING THE ONLY HEADLINE OUT NOW. GALES ARE NOW OCCURRING ALONG THE COAST WITH GUSTS AT THE MOMENT IN THE 35-40 KNOT RANGE. WAVES SHOULD PEAK THURSDAY MORNING IN THE 10-15 FOOT RANGE. MANY OF THE NEARSHORE BUOYS...SOUTH HAVEN...BRIDGMAN AND PORT SHELDON WERE PULLED FOR THE SEASON IN THE LAST FEW DAYS. MID LAKE BUOY CURRENTLY HAS 7 FOOTERS AND THAT SHOULD CONTINUE TO BUILD. && .HYDROLOGY... ISSUED AT 108 PM EDT WED OCT 28 2015 RAINFALL OVERNIGHT THROUGH THIS MORNING WHICH WAS NOT EXPECTED TO HAVE MUCH IMPACT ANYWAY HAS UNDERPERFORMED THUS FAR. TOTALS HAVE MOSTLY BEEN BETWEEN 0.25 AND 0.75 INCHES...WITH THE HIGHER END TOTALS CONFINED TO JACKSON COUNTY. THE GRAND RIVER AT JACKSON DID SPIKE TO 10.15 FEET THIS MORNING...BUT HAS FALLEN SINCE. BANKFULL IS 13 FEET. AN ADDITIONAL QUARTER TO HALF INCH OF RAIN IS POSSIBLE NOW THROUGH THURSDAY EVENING FROM SCATTERED LAKE ENHANCED SHOWERS. THIS DOES NOT POSE A SIGNIFICANT FLOODING RISK. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ844>849. && $$ UPDATE...DUKE SYNOPSIS...JK SHORT TERM...JK LONG TERM...MJS AVIATION...NJJ HYDROLOGY...EBW MARINE...DUKE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
213 AM EDT THU OCT 29 2015 .SYNOPSIS... A COLD FRONT WILL SWING ACROSS THE REGION OVERNIGHT AND EARLY THURSDAY...FOLLOWED BY DRIER CONDITIONS. A SEASONABLY COLDER LAKE EFFECT SHOWER/NORTHWEST FLOW PATTERN WILL END THE WEEK. THE TEMPERATURES SHOULD REBOUND NICELY OVER THE WEEKEND WITH FAIR WEATHER. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... RADAR SHOWS LOCALLY HEAVY RAIN WITH EMBEDDED THUNDER WORKING ACROSS CENTRAL AREAS AS OF 10 PM. ANOTHER MESO LOW/STRONG ROTATING THUNDERSTORM IS TRACKING NORTH THROUGH THE LOWER SUSQ VALLEY WHERE SEVERAL REPORTS OF WIND DAMAGE HAVE BEEN REPORTED. MESO ANAL HAS THE COLD FRONT APPROACHING THE OHIO/PA BORDER...WITH A LEE SIDE TROUGH FEATURE FORMING FURTHER EAST OVER THE SUSQ VALLEY. HRRR STILL SHOWS THE LARGEST MOST ORGANIZED AREA OF RAIN MOVING THROUGH BY AROUND MIDNIGHT OR INTO THE WEE HOURS...WITH JUST SCATTERED SHOWERS REMAINING FOR THE REMAINDER OF THE OVERNIGHT. COLD/OCCLUDED FRONT WILL MOVE THROUGH BY MORNING BUT THE REAL PUSH OF THE COOLER AIR WILL NOT BE IMMEDIATELY BEHIND THE FRONT...WITH THURSDAY STILL ENDING UP RELATIVELY MILD. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/... NOT MUCH RISE IS SEEN IN TEMPS ON THURSDAY. BUT SOME SUN SHOULD BREAK THROUGH POST-FRONT. WRAP AROUND/LAKE EFFECT MOISTURE WILL START TO CLOSE BACK IN ON THE NW THURS EVENING. WINDS MAY BE GUSTIER IN MANY LOCATIONS THURSDAY COMPARED TO TODAY AS THE DRY AIR MOVES IN AND DEEP VERTICAL MIXING TO 5-7 KFT AGL TAPS WESTERLY WINDS OF 50 KTS AT THE TOP OF THE LAYER. MEAN GUSTS WILL LIKELY BE IN THE 30-35 KTS RANGE...BUT A FEW COULD TICKLE THE 40 KT RANGE ACRS THE HIGHER TERRAIN. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... A BROAD CYCLONIC FLOW PATTERN ASSOCIATED WITH THE DEPARTING UPPER LEVEL TROUGH OVER SOUTHEASTERN CANADA WILL TRANSITION TOWARD A MILDER SOUTHWEST FLOW ALOFT THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THE EXACT TIMING/STRENGTH OF A SERIES OF SHORTWAVE EJECTIONS FROM THE SOUTHERN PLAINS IS YET-TO-BE DETERMINED AND WILL CONTINUE TO RESULT IN A LOWER CONFIDENCE FCST WITH RESPECT TO THE PCPN PATTERN OVER THE REGION. HOWEVER...THE 28/12Z MODEL AND ENSEMBLE GUIDANCE REMAIN VERY CONSISTENT IN BUILDING AN ANOMALOUS UPPER LEVEL RIDGE OVER THE EASTERN U.S. BY NEXT TUE-WED WHICH WILL ALMOST CERTAINLY SUPPORT MAX/MIN TEMPERATURES WELL ABOVE CLIMO INTO EARLY NOVEMBER. A SHOT OF MODESTLY COLDER AIR IN THE NW FLOW ALOFT WILL FOLLOW A SECONDARY FROPA AND BRING LAKE EFFECT/HIGHER ELEVATION SHOWERS TO THE NW ALLEGHENIES LATE THURSDAY NIGHT INTO EARLY FRIDAY MORNING. TEMPS STILL LOOK MARGINAL FOR SNOW BUT WILL KEEP MENTION OF RAIN/SNOW SHOWERS IN THE FCST. AS MENTIONED...CONFIDENCE IS LOW REGARDING OVERALL RAIN RISK AND TIMING/PLACEMENT/EXTENT LATER THIS WEEKEND AND INTO EARLY NEXT WEEK. DRY WX SHOULD PREVAIL DURING THE DAY ON SATURDAY. THE OP ECMWF AND GFS WANT TO DEVELOP A SRN STREAM LOW EARLY NEXT WEEK WITH A CONSENSUS APPROACH PLACING THE HIGHEST POPS ALONG AND SOUTH OF THE MASON DIXON LINE. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... COLD FRONT AND ACCOMPANYING HEAVY SHOWERS HAVE PUSHED EAST OF CENTRAL PA AT 06Z. IN IT/S WAKE...A DRIER SW FLOW IS BRINGING MORE FAVORABLE FLYING CONDS EARLY THIS MORNING. BIGGEST CONCERN DURING THE PRE-DAWN HOURS WILL BE RESIDUAL LOW LVL MOISTURE ASCENDING THE ALLEGHENY MTNS...WHICH COULD CONCEIVABLY DROP CIGS TO IFR AT KBFD/KJST. HOWEVER...AN EXAMINATION OF MDL SOUNDINGS AND UPSTREAM OBS SUGGEST MVFR CIGS ARE MORE LIKELY. DOWNSLOPING SW FLOW SHOULD RESULT IN PREDOMINANTLY VFR CONDS EAST OF THE MTNS EARLY THIS MORNING. A SECONDARY COLD FRONT ENTERING OHIO AT 05Z WILL SWEEP THRU CENTRAL PA BTWN 11Z-15Z...ACCOMPANIED BY A MARKED INCREASE IN WINDS AND PERHAPS A SHOWER IN SOME SPOTS. MUCH DRIER AIR BEHIND THIS COLD FRONT SHOULD BRING BREAKING CLOUDS AND WIDESPREAD VFR CONDS BY LATE AM. MAIN AVIATION CONCERN BEHIND THE FRONT WILL BE THE GUSTY WEST WINDS. BUFKIT SOUNDINGS SUPPORT FREQUENT GUSTS IN THE 25-30KT RANGE FROM LATE AM THRU LATE AFTN. EXPECT DIMINISHING WINDS THIS EVENING...AS BLYR COOLS STABILIZES. OUTLOOK... FRI...AM SHOWERS/LOW CIGS POSSIBLE AT KBFD. SAT...AM VALLEY FOG POSSIBLE AT KBFD/KAOO/KUNV/KIPT. SUN...AM SHOWERS/LOW CIGS POSSIBLE...MAINLY KBFD. MON...PATCHY AM FOG POSSIBLE. && .HYDROLOGY... RAINFALL AMOUNTS THROUGH THIS AFTERNOON HAVE GENERALLY RANGED BETWEEN 1 AND 2 INCHES. MINOR FLOODING DUE TO CLOGGED STORM DRAINS...PONDING/STANDING WATER WILL LIKELY CONTINUE INTO TONIGHT. MINOR RISES ARE FORECAST ON AREA RIVERS..STREAMS AND CREEKS BUT NO FLOODING IS EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LAMBERT LONG TERM...STEINBUGL AVIATION...FITZGERALD HYDROLOGY...
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1249 AM CDT THU OCT 29 2015 .UPDATE... ISSUED AT 1246 AM CDT THU OCT 29 2015 06Z AVIATION DISCUSSION UPDATED BELOW. UPDATE ISSUED AT 654 PM CDT WED OCT 28 2015 COLD AIR ADVECTION SNOW SHOWERS ARE TAPERING OFF THIS EVENING. ANOTHER BAND OF PRECIP IS MOVING IN FROM THE NORTHEAST AND WILL AFFECT MAINLY THE EASTERN CWA. WINDS HAVE DIMINISHED BELOW ADVISORY CRITERIA. HOWEVER WINDS ARE STILL EXPECTED TO INCREASE ALONG I-29 AGAIN TONIGHT SO HEADLINE POTENTIAL WILL NEED TO BE REEVALUATED. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 343 PM CDT WED OCT 28 2015 SCT SNOW SHOWERS CONTINUE TO MOVE SOUTHEAST ACROSS THE CWA WITH HEAVIER SQUALLS REDUCING VSBY DOWN TO AROUND 1SM AT TIMES. ALSO GETTING REPORTS OF SLEET/RAIN MIXING IN AS WELL. WILL CONTINUE TO SEE THIS ACTIVITY THROUGH SUNSET BEFORE THINGS DIMINISH. WILL THEN BE WATCHING THE VORT LOBE ROTATING SOUTHWARD INTO THE AREA LATER TONIGHT WITH ADDITIONAL LIGHT SNOW CHANCES OVER THE NORTHEAST CORNER OF THE CWA. THIS NEXT ROUND OF LIGHT SNOW MAY BRING SOME LIGHT ACCUMS OR A DUSTING TO THE NORTHEAST CWA...ESPECIALLY IN HIGHER TERRAIN. ALSO WATCHING WIND SPEEDS ACROSS THE AREA. ITS BEEN HIT AND MISS FOR WIND ADVISORY SPEEDS AS MOST AREAS HAVE BEEN FLIRTING WITH IT OR JUST BELOW CRITERIA. WILL LET THE CURRENT HEADLINE REMAIN IN PLACE UNTIL 00Z THOUGH AS A COUPLE 20Z OBS WERE IN LOW END CRITERIA SUSTAINED AND GUSTING CLOSE TO 45 MPH. OVERNIGHT...ANOTHER SURGE OF STRONGER WINDS IS EXPECTED OVER THE NORTHEAST CORNER OF THE CWA AS 925 MB WINDS INCREASE. MAV/LAV GUIDANCE FOR SISSETON ACTUALLY SHOWS SUSTAINED WINDS AROUND 30 KNOTS LATER THIS EVENING...BUT FEEL IT WILL BE LIKELY LOCALIZED TO SISSETON AND THE HIGHER ELEVATIONS NEAR SISSETON. PEEVER AND SUMMIT MAY SEE THE STRONGER WINDS AS WELL...BUT UNCERTAIN JUST HOW WIDESPREAD THE NEXT SURGE WILL BE TO WARRANT EXTENDING A WIND ADVISORY FOR A SMALL PORTION OF THE NORTHEAST CWA THROUGH 06Z OR 09Z. WILL LEAVE THIS DECISION FOR EVENING SHIFT. SPS MAY BE ABLE TO HANDLE THINGS AS WELL IF IT IS MORE OF A LOCALIZED EVENT. CLOUDS ARE THE NEXT ISSUE. STILL A WEALTH OF CLOUDS MOVING SOUTHWARD INTO THE AREA AND FEEL MUCH OF THE NIGHT WILL BE CLOUDY OR MOSTLY CLOUDY. AFTER SUNSET THERE SHOULD BE SOME EROSION OF THE CLOUDS ALONG THE WESTERN END. HARD TO DETERMINE JUST WHEN THE CLOUDS BEGIN TO DEPART/CLEAR OUT...BUT DID GO FOR A CLEARING TREND OVER CENTRAL SD AFTER MIDNIGHT. THIS MAY NOT BE THE CASE THOUGH GIVEN UPSTREAM TRENDS SO EVENING SHIFT MAY NEED TO ADJUST CLOUD COVER. RAP 925-850 RH ACTUALLY KEEPS HIGH VALUES OVER MUCH OF THE CWA THE ENTIRE NIGHT. WITH THE CLOUDS AND WINDS STAYING IN PLACE...TEMPS WILL NOT FALL A HUGE AMOUNT. REST OF THE SHORT TERM IS RATHER QUIET AS A SFC HIGH MOVES OVER THE AREA ON THURSDAY. THIS WILL BRING LIGHTER WINDS...ESPECIALLY BY AFTERNOON/EVENING. LOWS STILL TRICKY TO FORECAST THURSDAY NIGHT AS THE SFC HIGH MOVES OFF PRETTY QUICKLY AND RETURN FLOW SOUTHERLY WINDS AND WARM AIR ADVECTION ARE ALREADY ONGOING BY 12Z FRIDAY. WILL PROBABLY HAVE A SHARP DROP IN THE EVENING THEN SEE READINGS STEADY OFF OR EVEN RISE A FEW DEGREES AS WINDS INCREASE AND HIGH LEVEL CLOUDS MOVE IN. ALTHOUGH...AS WE TYPICALLY SEE VERY OFTEN...FAVORED COLD SPOTS AND VALLEYS WILL LIKELY NOT TAP INTO THE STRONGER WINDS AND STAY AROUND 5 KNOTS OR SO WHICH WILL ALLOW FOR TEMPS TO FALL QUITE NICELY. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 343 PM CDT WED OCT 28 2015 NEAR ZONAL FLOW ALOFT IS EXPECTED THROUGH THE FIRST HALF OF THE LONG TERM FORECAST. MODELS DO SHOW A COUPLE OF SHORTWAVES SKIRTING JUST NORTH OF THE REGION...BUT THE FORECAST REMAINS LARGELY DRY FOR OUR CWA. THE FLOW WILL TRANSITION TO THE SOUTHWEST AS A LONG WAVE TROUGH MOVES OVER THE WESTERN CONUS BY EARLY NEXT WEEK. MODEL SOLUTIONS BEGIN TO SHOW SOME DISCREPANCIES BY THIS POINT...BUT PRECIPITATION CHANCES RETURN TO THE FORECAST BY THE TUESDAY/WEDNESDAY TIME FRAME REGARDLESS. THE MILD PACIFIC FLOW WILL ENSURE ABOVE NORMAL TEMPERATURES. IN FACT BY SUNDAY AND MONDAY 850 TEMPS ARE PROGGED IN THE TEENS...AND CURRENT FORECAST HIGH TEMPERATURES WILL BE PUSHING 15 TO 20 DEGREES ABOVE NORMAL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1246 AM CDT THU OCT 29 2015 MVFR/LOW VFR CIGS WILL AFFECT MOST OF THE REGION OVERNIGHT. NORTHWEST WINDS OF 15 TO 30 KTS WILL SLOWLY DIMINISH BY 18Z. AS WINDS BECOME LIGHT AND VARIABLE CIGS WILL LIFT TO VFR. AN AREA OF RAIN AND SNOW SHOWERS CONTINUES TO SPREAD ACROSS NORTHEASTERN SD. ANY IMPACT WILL BE MINIMAL THOUGH THE PRECIP MAY REACH AS FAR AS KATY BEFORE EXITING BY 12Z. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...MOHR SHORT TERM...TMT LONG TERM...SERR AVIATION...MOHR
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1134 PM CDT WED OCT 28 2015 .UPDATE... FOR 06Z AVIATION. && .DISCUSSION... LATEST RADAR IMAGERY SHOWS PRECIP HAS EXITED THE AREA ATTM. HOWEVER...ALL MODELS INCLUDING THE LATEST HRRR SHOW ADDITIONAL ISOLATED SHOWERS MOVING ACROSS THE CWA LATER THIS EVENING AND OVERNIGHT AS COLD FRONT APPROACHES THE AREA. THUS WILL SHOW A SLIGHT CHANCE POP FOR ALL ZONES THROUGH 06Z...THEN JUST THE SOUTHEAST HALF AFTER 06Z. WITH THE VERY MOIST GROUNDS FROM THE RECENT RAINFALL...SKIES CLEARING OUT AND WINDS BECOMING LIGHT...ALSO EXPECT PATCHY FOG TO DEVELOP AREAWIDE AFTER MIDNIGHT. REST OF FORECAST IS ON TRACK. SHAMBURGER && .AVIATION... 06Z TAF DISCUSSION. MODELS ARE STILL HINTING AT THE POSSIBILITY FOR MVFR FOG AT ALL TERMINALS THIS MORNING...AND WITH MVFR/IFR CIGS POSSIBLE FOR KCSV. OTHERWISE...LOOK FOR VFR CONDITIONS AND WESTERLY WINDS TO INCREASE MID TO LATE MORNING FOR ALL TERMINALS. WINDS SHOULD CALM DOWN BELOW 5 KNOTS AFTER 00Z. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
533 AM EDT THU OCT 29 2015 .SYNOPSIS... A COLD FRONT WILL MOVE EAST ACROSS THE REGION TODAY. HIGH PRESSURE ARRIVES TONIGHT INTO FRIDAY FROM THE WEST. THIS HIGH WILL MOVE OFFSHORE THIS WEEKEND...WHILE ANOTHER LOW PRESSURE AREA FORMS OVER THE LOWER MISSISSIPPI VALLEY BRING MORE MOISTURE OUR WAY SUNDAY INTO MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 352 AM EDT THURSDAY... THE COMBINATION OF LIGHT WINDS AND SOME CLEARING BEHIND THE FIRST COLD FRONT RESULTED IN PATCHY LOW CLOUDS AND FOG THIS MORNING. FOG IS QUITE VARIABLE AND GENERALLY IN THE VALLEYS. MORNING FOG WILL MIX OUT QUICKLY AS WIND SPEEDS INCREASE AHEAD OF ANOTHER FRONTAL BOUNDARY. THE SECOND COLD FRONT WILL PUSH EAST ACROSS THE REGION TODAY AND REACH THE ATLANTIC COAST TONIGHT. THE HIGHRESW- ARW-EAST...RNK WRFARW...NAM AND GFS SHOWED SOME SCATTERED MORNING SHOWERS IN THE MOUNTAINS. THE HRRR PLACED SOME ISOLATED SHOWERS IN THE FOOTHILLS THIS AFTERNOON AS A FRONT TRAVELS ACROSS THE AREA. BELIEVE THAT THE SHOWERS ARE OVERDONE WITH THE WEST FLOW. UPSLOPE CLOUDS WILL LINGER IN THE WESTERN MOUNTAINS. WHILE...SUNSHINE WILL RETURN TO THE EAST THIS AFTERNOON. HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE UPPER 50S IN THE NORTHWEST MOUNTAINS TO THE MID 70S IN THE PIEDMONT. DRIER AIR WILL FILTER INTO OUR REGION TONIGHT...WHILE HIGH PRESSURE REMAINS WEST OF THE AREA WITH NORTHWEST FLOW WEAKENING. LOW LEVEL THICKNESSES COOL ENOUGH THAT LOW TEMPERATURES WILL VARY FROM THE MID TO UPPER 30S IN THE MOUNTAINS TO THE LOWER 40S IN THE PIEDMONT. && .SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/... AS OF 445 AM EDT THURSDAY... WHAT STARTS OUT INITIALLY AS A PROGRESSIVE FLOW BECOMES SPLIT AND BLOCKED THROUGH THIS PERIOD AS A DEEP UPPER LOW ATTEMPTS TO SHIFT OUT OF THE SOUTHWEST U.S. AND AN UPPER RIDGE DEVELOPS OFF THE SOUTHEAST U.S. COAST. A LARGE HIGH PRESSURE AREA WILL DRIFT INTO THE REGION FROM THE WEST FRIDAY WITH WEST-NORTHWEST FLOW ALOFT. DECREASING WINDS...SUNNY SKIES...AND SEASONABLE TEMPERATURES ARE EXPECTED. 850MB TEMPS REMAIN ABOVE FREEZING EXCEPT IN THE FAR NORTH...SO OTHER THAN THE HIGHER MOUNTAINS AND A FEW DEEPER VALLEYS WITHIN THE MOUNTAINS...FREEZING TEMPERATURES ARE NOT EXPECTED. DURING THE DAY SATURDAY...THE SURFACE HIGH WILL DRIFT OFF THE MID-ATLANTIC COAST AS A FAST MOVING NORTHERN STREAM SHORT WAVE ATTEMPTS TO PICK UP THE LINGERING UPPER LOW ACROSS TEXAS. MEANWHILE...A BLOCKING 592DM UPPER RIDGE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST. THE NORTHERN STREAM SHORT WAVE WILL SPREAD PRECIPITATION INTO OUR REGION BY SATURDAY EVENING...BUT ESPECIALLY INTO SUNDAY MORNING. BY SUNDAY AFTERNOON...THE NORTHERN STREAM SHORT WAVE HAS MOVED WELL NORTHEAST OF THE REGION...BUT THE SOUTHERN STREAM UPPER SHORT WAVE ACROSS AL/GA WILL BE LEFT BEHIND...ALBEIT SHEARING OUT. A BAROCLINIC ZONE WILL LINGER ACROSS THE SOUTHEAST STATES AND POTENTIALLY NORTHEAST INTO VA. WHILE THE MODELS HANDLE THE TRACK AND TIMING OF THE NORTHERN STREAM SHORT WAVE SAT-SUN WELL...THE SUBSEQUENT HANDLING OF THE UPPER TROUGH ACROSS THE SOUTHEAST STATES IS POORLY HANDLED. THE ECMWF TRACKS MUCH OF THE MOISTURE WELL NORTH INTO THE MID- ATLANTIC...WHILE THE GFS RAPIDLY TAKES IT EAST-SOUTHEAST OFF THE ATLANTIC COAST. THE ECMWF SOLUTION COULD POTENTIALLY LEAD TO HYDRO ISSUES...WHILE THE GFS WOULD NOT. WPC HAS INDICATED THAT A SWATH OF HEAVY RAIN WILL TRACK FROM NEAR BHM-ATL-CAE...REMAINING WELL SOUTH OF OUR REGION WITH GENERAL AMOUNTS OF 1.0 INCH IN OUR SOUTHERN CWA TO 1/2 INCH NORTH. THIS WILL NOT BE A WEDGE EVENT...MORE OF A SOUTHWEST FLOW EVENT...AND THUS THERE SHOULD NOT BE ENHANCEMENT ALONG THE BLUE RIDGE AS WITH SOME OF OUR PREVIOUS EVENTS. NONETHELESS...THE GROUND IS NOW SATURATED FROM GENERAL 1.5 TO 2.5 INCH RAINFALL LAST TWO DAYS. THUS...TO ACCOUNT FOR UNCERTAINTY..WILL WORD EXTENDED PORTION OF HWO AS "PROBABILITY IS LOW" RATHER THAN "NO HAZARDS". ALSO IN THIS REGARD...HAVE CARRIED LOW CHANCE/SLIGHT CHANCE POPS LONGER IN THESE PERIODS THAN I REALLY WANTED TO IN DEFERENCE TO THE ECMWF. TEMPERATURES WILL REMAIN ABOVE SEASONAL NORMALS THROUGH THE PERIOD...ON THE AVERAGE OF 10 DEGREES. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF 415 AM EDT THURSDAY... THE BAROCLINIC ZONE TO OUR SOUTHEAST SHOULD FINALLY BE KICKED OUT TO SEA BY TUE AS ANOTHER DEEP UPPER TROUGH BUILDS INTO THE SOUTHEAST U.S. IN RESPONSE...A HIGH AMPLITUDE 592DM RIDGE WILL BUILD ACROSS THE EASTERN U.S....CENTERED ACROSS FL/GA. MEANWHILE...A NEW BAROCLINIC ZONE WILL DEVELOP ACROSS TEXAS INTO THE WESTERN TN VALLEY. GIVEN THE INCREASING AMPLITUDE OF THE FLOW AND BLOCKING RIDGE ACROSS THE SOUTHEAST...CONFIDENCE IN WHEN THIS AREA OF RAIN WILL REACH OUR AREA IS LOW AT THIS TIME. HAVE LEFT THE LATER PERIODS OF THE EXTENDED PERIOD DRY FOR NOW. TEMPERATURES WILL REMAIN WELL ABOVE NORMAL THROUGH THE PERIOD WITH SEVERAL DAYS IN THE 70S POSSIBLE ACROSS THE PIEDMONT...60S ACROSS THE MOUNTAINS. MIN TEMPS WILL REMAIN WELL ABOVE FREEZING. && .AVIATION /09Z THURSDAY THROUGH MONDAY/... AS OF 130 AM EDT THURSDAY... LIGHT WINDS AND SOME CLEARING HAVE RESULT IN LOW CLOUDS AND PATCHES OF FOG THIS MORNING. ADDED SOME LIFR FOG TO KBCB AND KLYH AND MVFR FOG TO KROA AND KDAN. SCATTERED SHOWERS WILL MOVE EAST ACROSS WESTERN PORTIONS OF AREA THIS MORNING. A COLD FRONTAL BOUNDARY TO OUR WEST SHOULD REACH THE MOUNTAINS AROUND 12Z/8AM AND EAST OF THE BLUE RIDGE THIS AFTERNOON. LOW LEVEL MOISTURE WILL FILL BACK IN OVER THE TYPICAL WESTERN UPSLOPE AREAS AND KLWB AND KBLF THIS MORNING WITH MVFR CEILINGS. WIND SPEEDS WILL INCREASE TODAY AND BECOME GUSTY THIS AFTERNOON. BEHIND THE FRONT BUFKIT WAS SHOWING ENOUGH MOMENTUM TRANSFER FOR WIND GUSTS FROM THE WEST AT 20 TO 25 KNOTS ONCE MIXING BEGINS. CONDITIONS WILL IMPROVE EAST OF THE BLUE RIDGE...WITH VFR CLOUDS BECOMING SCATTERED ON THURSDAY DUE TO DRIER AIR MOVING INTO THE REGION AND A DEEP WEST DOWNSLOPE WIND. VFR CONDITIONS EXPECTED THURSDAY NIGHT. MEDIUM CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE PERIOD. EXTENDED AVIATION DISCUSSION... IMPROVING CONDITIONS ARE EXPECTED FRI AS HIGH PRESSURE SPREADS ACROSS THE REGION WITH MOSTLY VFR CONDITIONS. WINDS WILL DIMINISH FRIDAY. THE NEXT CHANCE FOR RAIN AND SUB-VFR CIGS WILL COME SUNDAY-MONDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...KK/WP NEAR TERM...KK SHORT TERM...RAB LONG TERM...RAB/WP AVIATION...AMS/KK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
353 AM EDT THU OCT 29 2015 .SYNOPSIS... A COLD FRONT WILL MOVE EAST ACROSS THE REGION TODAY. HIGH PRESSURE ARRIVES TONIGHT INTO FRIDAY FROM THE WEST. THIS HIGH WILL MOVE OFFSHORE THIS WEEKEND...WHILE ANOTHER LOW PRESSURE AREA FORMS OVER THE LOWER MISSISSIPPI VALLEY BRING MORE MOISTURE OUR WAY SUNDAY INTO MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 352 AM EDT THURSDAY... THE COMBINATION OF LIGHT WINDS AND SOME CLEARING BEHIND THE FIRST COLD FRONT RESULTED IN PATCHY LOW CLOUDS AND FOG THIS MORNING. FOG IS QUITE VARIABLE AND GENERALLY IN THE VALLEYS. MORNING FOG WILL MIX OUT QUICKLY AS WIND SPEEDS INCREASE AHEAD OF ANOTHER FRONTAL BOUNDARY. THE SECOND COLD FRONT WILL PUSH EAST ACROSS THE REGION TODAY AND REACH THE ATLANTIC COAST TONIGHT. THE HIGHRESW- ARW-EAST...RNK WRFARW...NAM AND GFS SHOWED SOME SCATTERED MORNING SHOWERS IN THE MOUNTAINS. THE HRRR PLACED SOME ISOLATED SHOWERS IN THE FOOTHILLS THIS AFTERNOON AS A FRONT TRAVELS ACROSS THE AREA. BELIEVE THAT THE SHOWERS ARE OVERDONE WITH THE WEST FLOW. UPSLOPE CLOUDS WILL LINGER IN THE WESTERN MOUNTAINS. WHILE...SUNSHINE WILL RETURN TO THE EAST THIS AFTERNOON. HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE UPPER 50S IN THE NORTHWEST MOUNTAINS TO THE MID 70S IN THE PIEDMONT. DRIER AIR WILL FILTER INTO OUR REGION TONIGHT...WHILE HIGH PRESSURE REMAINS WEST OF THE AREA WITH NORTHWEST FLOW WEAKENING. LOW LEVEL THICKNESSES COOL ENOUGH THAT LOW TEMPERATURES WILL VARY FROM THE MID TO UPPER 30S IN THE MOUNTAINS TO THE LOWER 40S IN THE PIEDMONT. && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... AS OF 310 PM EDT WEDNESDAY... THE LARGE HIGH PRESSURE OVER THE MID MISS VALLEY WILL MOVE EAST FRIDAY AND WE SHOULD SEE PLENTY OF SUNSHINE. COOLER AIR WILL FILTER INTO THE REGION AS THE UPPER LEVEL TROUGH TRACKS EAST OF THE OHIO VALLEY. TEMPERATURES WILL FAIL TO REACH SEASONAL LEVELS FRIDAY AS COOLER AIR CONTINUES TO PUSH INTO THE REGION. SATURDAY MORNING TEMPERATURES WILL BE IN THE 30S WITH SOME MOUNTAINS LOCATIONS DROPPING INTO THE UPPER 20S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 320 PM EDT WEDNESDAY... THIS FORECAST TURNS MORE TOWARD SW FLOW ALOFT WITH A SPLIT FLOW PATTERN...WITH TEMPERATURES MODERATING. UPPER TROUGH OVER THE LOWER MISS VALLEY SUNDAY WILL HEAD INTO THE MOUNTAINS BY MONDAY BRINGING A GOOD CHANCE OF SHOWERS. DIFFERENCES ON TIMING OF SHOWER CHANCES EXISTS...WITH SOME MODELS SHOWING SHOWERS ARRIVING BY SUNDAY MORNING INTO THE MOUNTAINS. WILL INTRODUCE LOW CHANCE POPS LATE SAT NIGHT INTO THE MOUNTAINS...WITH BETTER CHANCE WORKING SW TO NE SUNDAY AFTERNOON. BY LATE MONDAY NIGHT TO TUESDAY THE FRONTAL BOUNDARY SHOULD BE EXITING TO OUR SE...BUT FLOW AROUND THE HIGH PRESSURE OVER THE NEW ENGLAND COAST MAY KEEP SHOWERS GOING AIDED BY ATLANTIC MOISTURE OVERRIDING THE FRONT FROM GEORGIA TO NC OUTER BANKS. WILL STAY WITH LOW POPS TUESDAY WITH COOLER TEMPS. BY WEDNESDAY...THE HIGHS STARTS TO MOVE SOUTHEAST OFF THE MID ATLANTIC COAST. ATTM WILL KEEP IT MAINLY DRY WITH DEEPER MOISTURE MOVING TO THE COAST AND OFFSHORE. && .AVIATION /08Z THURSDAY THROUGH MONDAY/... AS OF 130 AM EDT THURSDAY... LIGHT WINDS AND SOME CLEARING HAVE RESULT IN LOW CLOUDS AND PATCHES OF FOG THIS MORNING. ADDED SOME LIFR FOG TO KBCB AND KLYH AND MVFR FOG TO KROA AND KDAN. SCATTERED SHOWERS WILL MOVE EAST ACROSS WESTERN PORTIONS OF AREA THIS MORNING. A COLD FRONTAL BOUNDARY TO OUR WEST SHOULD REACH THE MOUNTAINS AROUND 12Z/8AM AND EAST OF THE BLUE RIDGE THIS AFTERNOON. LOW LEVEL MOISTURE WILL FILL BACK IN OVER THE TYPICAL WESTERN UPSLOPE AREAS AND KLWB AND KBLF THIS MORNING WITH MVFR CEILINGS. WIND SPEEDS WILL INCREASE TODAY AND BECOME GUSTY THIS AFTERNOON. BEHIND THE FRONT BUFKIT WAS SHOWING ENOUGH MOMENTUM TRANSFER FOR WIND GUSTS FROM THE WEST AT 20 TO 25 KNOTS ONCE MIXING BEGINS. CONDITIONS WILL IMPROVE EAST OF THE BLUE RIDGE...WITH VFR CLOUDS BECOMING SCATTERED ON THURSDAY DUE TO DRIER AIR MOVING INTO THE REGION AND A DEEP WEST DOWNSLOPE WIND. VFR CONDITIONS EXPECTED THURSDAY NIGHT. MEDIUM CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE PERIOD. EXTENDED AVIATION DISCUSSION... IMPROVING CONDITIONS ARE EXPECTED FRI AS HIGH PRESSURE SPREADS ACROSS THE REGION WITH MOSTLY VFR CONDITIONS. WINDS WILL DIMINISH FRIDAY. THE NEXT CHANCE FOR RAIN AND SUB-VFR CIGS WILL COME SUNDAY-MONDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...KK/WP NEAR TERM...KK SHORT TERM...RCS/WP LONG TERM...MBS/WP AVIATION...AMS/KK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
151 AM EDT THU OCT 29 2015 .SYNOPSIS... ONE FRONT MOVES ACROSS THIS EVENING FOLLOWED BY ANOTHER FRONT THURSDAY WHICH WILL BRING DRIER WEATHER. HIGH PRESSURE ARRIVES THURSDAY NIGHT INTO FRIDAY FROM THE WEST. THIS HIGH WILL MOVE OFFSHORE THIS WEEKEND WHILE ANOTHER LOW PRESSURE AREA FORMS OVER THE LOWER MISSISSIPPI VALLEY BRING MORE MOISTURE OUR WAY SUNDAY INTO MONDAY. && .NEAR TERM /THROUGH TODAY/... AS OF 1130 PM EDT WEDNESDAY... A MAJORITY OF THE SHOWERS HAVE MOVED EAST OUT OF THE FORECAST AREA. LATEST HRRR SHOWED AN AREA OF PRECIPITATION IN THE FAR SOUTHWEST COUNTY WARNING AREA THROUGH 06Z/2AM...OTHERWISE THE DRYING TREND WILL CONTINUE. HAVE TRIMMED BACK THE PROBABILITY OF PRECIPITATION TO REFLECT THE LATEST RADAR TRENDS. SINCE FRONT WILL NOT REACH WESTERN COUNTIES OF THE FORECAST AREA UNTIL AFTER 6AM...HAVE ADJUSTED THE MINIMUM TEMPERATURES A FEW DEGREES WARMER. WE SHOULD REACH A POINT WHERE DRIER AIR WILL MOVE IN FROM THE SOUTHWEST CLEARING THINGS OUT LEE OF THE BLUE RIDGE...FOLLOWED BY LINGERING UPSLOPE SE WV/FAR SW VA/NW NC OVERNIGHT INTO THURSDAY. MAY SEE ANOTHER SHOT OF SHOWERS THURSDAY IN THE SE WV MTNS TOWARD NC...BUT EAST OF THIS WILL SEE MORE SUNSHINE. THE NAM IS ACTUALLY KEEPING THE SHOWER THREAT MOVING EAST OF THE MTNS INTO NC THURSDAY AFTERNOON. FOR NOW I WILL KEEP IT DRY WITH SOME CLOUD COVER LINGERING HERE. NW WINDS WILL BE GUSTY LATE TONIGHT-THURSDAY BUT ONLY IN THE 20-30 MPH RANGE. LOWS TONIGHT WILL BE ELEVATED AHEAD OF THE FRONT STAYING IN THE 50S...WITH SOME 40S BY MORNING OVER THE HIGHER RIDGES. DESPITE BEING POST-FRONT THURSDAY...THE UPPER FLOW REMAINS SW WITH AXIS OF NEGATIVE TILT TROUGH OVER THE MID ATLANTIC WITH YET ANOTHER VORT MOVING ACROSS THE OHIO VALLEY. NW FLOW AT TIMES WITH SUNSHINE WILL WARM THINGS UP IN THE LEE OF THE MTNS...SO EXPECT HIGHS THURSDAY IN THE LOWER 70S EAST OF THE MOUNTAINS...WITH 60S ELSEWHERE. THURSDAY NIGHT...HIGH PRESSURE REMAINS WEST OF THE AREA WITH NW FLOW WEAKENING. LOW LVL THICKNESSES COOL ENOUGH THAT LOWS WILL RANGE FROM THE MID TO UPPER 30S MOUNTAINS...TO LOWER 40S PIEDMONT. && .SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... AS OF 310 PM EDT WEDNESDAY... THE LARGE HIGH PRESSURE OVER THE MID MISS VALLEY WILL MOVE EAST FRIDAY AND WE SHOULD SEE PLENTY OF SUNSHINE. COOLER AIR WILL FILTER INTO THE REGION AS THE UPPER LEVEL TROUGH TRACKS EAST OF THE OHIO VALLEY. TEMPERATURES WILL FAIL TO REACH SEASONAL LEVELS FRIDAY AS COOLER AIR CONTINUES TO PUSH INTO THE REGION. SATURDAY MORNING TEMPERATURES WILL BE IN THE 30S WITH SOME MOUNTAINS LOCATIONS DROPPING INTO THE UPPER 20S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 320 PM EDT WEDNESDAY... THIS FORECAST TURNS MORE TOWARD SW FLOW ALOFT WITH A SPLIT FLOW PATTERN...WITH TEMPERATURES MODERATING. UPPER TROUGH OVER THE LOWER MISS VALLEY SUNDAY WILL HEAD INTO THE MOUNTAINS BY MONDAY BRINGING A GOOD CHANCE OF SHOWERS. DIFFERENCES ON TIMING OF SHOWER CHANCES EXISTS...WITH SOME MODELS SHOWING SHOWERS ARRIVING BY SUNDAY MORNING INTO THE MOUNTAINS. WILL INTRODUCE LOW CHANCE POPS LATE SAT NIGHT INTO THE MOUNTAINS...WITH BETTER CHANCE WORKING SW TO NE SUNDAY AFTERNOON. BY LATE MONDAY NIGHT TO TUESDAY THE FRONTAL BOUNDARY SHOULD BE EXITING TO OUR SE...BUT FLOW AROUND THE HIGH PRESSURE OVER THE NEW ENGLAND COAST MAY KEEP SHOWERS GOING AIDED BY ATLANTIC MOISTURE OVERRIDING THE FRONT FROM GEORGIA TO NC OUTER BANKS. WILL STAY WITH LOW POPS TUESDAY WITH COOLER TEMPS. BY WEDNESDAY...THE HIGHS STARTS TO MOVE SOUTHEAST OFF THE MID ATLANTIC COAST. ATTM WILL KEEP IT MAINLY DRY WITH DEEPER MOISTURE MOVING TO THE COAST AND OFFSHORE. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 130 AM EDT THURSDAY... LIGHT WINDS AND SOME CLEARING HAVE RESULT IN LOW CLOUDS AND PATCHES OF FOG THIS MORNING. ADDED SOME LIFR FOG TO KBCB AND KLYH AND MVFR FOG TO KROA AND KDAN. SCATTERED SHOWERS WILL MOVE EAST ACROSS WESTERN PORTIONS OF AREA THIS MORNING. A COLD FRONTAL BOUNDARY TO OUR WEST SHOULD REACH THE MOUNTAINS AROUND 12Z/8AM AND EAST OF THE BLUE RIDGE THIS AFTERNOON. LOW LEVEL MOISTURE WILL FILL BACK IN OVER THE TYPICAL WESTERN UPSLOPE AREAS AND KLWB AND KBLF THIS MORNING WITH MVFR CEILINGS. WIND SPEEDS WILL INCREASE TODAY AND BECOME GUSTY THIS AFTERNOON. BEHIND THE FRONT BUFKIT WAS SHOWING ENOUGH MOMENTUM TRANSFER FOR WIND GUSTS FROM THE WEST AT 20 TO 25 KNOTS ONCE MIXING BEGINS. CONDITIONS WILL IMPROVE EAST OF THE BLUE RIDGE...WITH VFR CLOUDS BECOMING SCATTERED ON THURSDAY DUE TO DRIER AIR MOVING INTO THE REGION AND A DEEP WEST DOWNSLOPE WIND. VFR CONDITIONS EXPECTED THURSDAY NIGHT. MEDIUM CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE PERIOD. EXTENDED AVIATION DISCUSSION... IMPROVING CONDITIONS ARE EXPECTED FRI AS HIGH PRESSURE SPREADS ACROSS THE REGION WITH MOSTLY VFR CONDITIONS. WINDS WILL DIMINISH FRIDAY. THE NEXT CHANCE FOR RAIN AND SUB-VFR CIGS WILL COME SUNDAY-MONDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...WP NEAR TERM...AMS/CF/WP SHORT TERM...RCS/WP LONG TERM...MBS/WP AVIATION...AMS/KK
AREA FORECAST DISCUSSION
NWS PORTLAND OR
257 AM PDT THU OCT 29 2015 .SYNOPSIS...SHOWERS ARE DECREASING THIS MORNING AS HIGH PRESSURE MOVES INTO OREGON. LEFTOVER INSTABILITY MAY CAUSE A FEW MORE SHOWERS TO POP UP THIS AFTERNOON...MAINLY IN THE HIGHER TERRAIN. ATTENTION THEN TURNS TO THE FIRST WIDESPREAD HEAVY RAIN EVENT OF THE SEASON WHICH WILL IMPACT THE REGION FRIDAY INTO SATURDAY ALONG WITH BLUSTERY SOUTH TO SOUTHWEST WINDS. THE MAIN FRONTAL ZONE WILL PUSH SOUTH ACROSS OREGON AS A COLD FRONT LATER SATURDAY OR SATURDAY NIGHT...WITH RAIN TAPERING TO SHOWERS BEHIND THE FRONT. SNOW LEVELS WILL BE LOWERING BEHIND THE FRONT...AND ADDITIONAL DISTURBANCES MAY BRING THE FIRST SIGNIFICANT SNOWFALL OF THE SEASON FOR THE CASCADES EARLY NEXT WEEK. OTHERWISE EXPECT COOL AND SHOWERY WEATHER SUNDAY AND MONDAY...WITH SHOWERS TAPERING OFF MIDWEEK. && .SHORT TERM...TODAY THROUGH SATURDAY...ISSUED A QUICK UPDATE TO THE FORECAST EARLIER IN THE SHIFT TO ACCOUNT FOR SOME FOG TRYING TO FORM UNDER ANY BREAKS IN THE HIGHER CLOUDS. FOG SHOULD BE PATCHY...BUT CANNOT BE RULED OUT WITH THE GROUND SO MOIST FROM RECENT RAINS. LOOKING AT THE BIGGER PICTURE...HIGH PRESSURE IS BUILDING INTO OREGON THIS MORNING...CAUSING SHOWERS TO DECREASE ESPECIALLY IN THE LOWLANDS. MOIST WESTERLY LOW-LEVEL FLOW IS CAUSING OROGRAPHIC SHOWERS TO PERSIST IN THE CASCADES DESPITE THE HIGHER PRESSURE. SOME SHALLOW INSTABILITY LINGERS AS WELL...BECOMING INCREASINGLY CAPPED AT 700 MB BY WARMER AIR MOVING IN ALOFT. LAPSE RATES BELOW 700 MB REMAIN STEEP ENOUGH ON GFS/NAM SOUNDINGS TO PROMOTE SHOWERS REDEVELOPING THIS AFTERNOON...THOUGH THEY WILL PROBABLY REMAIN ISOLATED IN MUCH OF THE WILLAMETTE VALLEY DUE TO DOWNSLOPE FLOW OFF THE LEE OF THE COAST RANGE. ANY LINGERING SHOWERS SHOULD COLLAPSE AROUND SUNSET WITH THE LOSS OF SOLAR HEATING. WHILE LOWER CLOUDS AND SHOWERS DIMINISH THIS EVENING...EXPECT HIGH CLOUDS TO BE ON THE INCREASE AS THE PACIFIC JET STREAM TAKES AIM AT THE PACIFIC NORTHWEST. WATER VAPOR IMAGERY SHOWS A DECENT ATMOSPHERIC RIVER TAKING SHAPE FROM THE SUBTROPICS NEAR THE DATELINE TO AROUND 45N/140W...WITH PRECIPITABLE WATER VALUES APPROACHING 1.5 INCHES WITHIN ITS CORE. 00Z GFS AND GEFS MEAN CONTINUE TO SHOW THE MAIN AXIS OF INTEGRATED VAPOR TRANSPORT AIMED AT THE NORTHERN HALF OF OUR CWA THROUGH FRIDAY. IT DOES APPEAR THERE WILL BE A SLIGHT NORTHWARD SHIFT IN THE IVT AXIS FRI NIGHT/EARLY SAT MORNING BEFORE IT COMES BACK SOUTHWARD ACROSS WESTERN OREGON SATURDAY AND SATURDAY NIGHT. THIS WOULD AGREE WITH WHAT THE ECMWF AND GEM HAVE BEEN SHOWING FOR THE PAST COUPLE DAYS...AND MAKES A LOT OF SENSE GIVEN THAT THE STRONG JET AND BAROCLINIC ZONE IS LIKELY TO PROMOTE CYCLOGENESIS AS FAST-MOVING WAVES OF LOW PRESSURE RACE EASTWARD ALONG THE STALLED FRONTAL ZONE. ANY STRONGER WAVES OF LOW PRESSURE WOULD TEND TO CAUSE WIGGLES IN THE FRONTAL ZONE AND ATMOSPHERIC RIVER...PUSHING THE AREA OF HEAVIEST RAIN NORTH AHEAD OF THEM AND SOUTH BEHIND THEM. MODELS WILL LIKELY STRUGGLE WITH THESE INDIVIDUAL WAVES DUE TO THEIR SPEED AND SUBTLETY. EVEN A SHORT BREAK IN THE HEAVIEST RAIN WOULD GO A LONG WAY TOWARD EASING ANY MINOR HYDROLOGIC CONCERNS WE HAVE. FOR NOW WE ARE SHOWING TWO PRIMARY PERIODS OF HEAVIER RAIN ACROSS THE NORTHERN HALF OF OUR CWA...FRI AFTERNOON/EVENING AS A WARM FRONT LIFTS THROUGH AND AGAIN SAT AFTERNOON AS THE FRONTAL ZONE COMES BACK SOUTH AS A COLD FRONT. IN BETWEEN...OUR QPF IS MORE MODEST LATE FRI NIGHT AND SAT MORNING...ESPECIALLY IN THE WILLAMETTE VALLEY WHERE DECENT RAIN SHADOWING WILL BE OCCURRING. THE JURY IS STILL OUT ON WHETHER OR NOT THE HEAVY RAIN WILL BE AFFECTING THE PORTLAND METRO FOR THE TRICK OR TREATERS HALLOWEEN EVENING...WITH A HIGHER LIKELIHOOD OF HEAVIER RAIN CONTINUING INTO THE EVENING FOR AREAS SALEM SOUTHWARD. 00Z GFS/ECMWF SUGGEST STEADY RAIN WILL BE TAPERING OFF AROUND 6 PM SAT EVENING IN THE PDX METRO...WHILE OTHER MODELS SUCH AS THE 00Z/06Z NAM AND 00Z GEM HOLD ONTO THE RAIN A LITTLE LONGER. OVERALL QPF AMOUNTS IN OUR FORECAST HAVE NOT CHANGED MUCH OVER THE PAST 24 HOURS. STILL LOOKING LIKE 4-8 INCHES IN THE WILLAPA HILLS... NORTH OREGON COAST RANGE...AND THE CASCADES FROM SOUTHERN WA TO MOUNT HOOD. GENERAL 2-4 INCH TOTALS ARE FORECAST FOR THE COAST AS WELL AS THE HIGHER TERRAIN OF OUR SOUTHERN ZONES. INLAND VALLEYS WILL SEE SIGNIFICANT RAIN SHADOWING...ESPECIALLY WEST OF I-5 AND IN THE LOWER HOOD RIVER VALLEY...ONLY 1-2 INCHES ARE EXPECTED IN THESE AREAS WITH SOME HIGHER AMOUNTS POSSIBLE NEAR THE CASCADE FOOTHILLS. THIS WILL BE ENOUGH TO CAUSE SIGNIFICANT RISES ON AREA RIVERS...BUT NOT ENOUGH TO CAUSE WIDESPREAD FLOODING PROBLEMS. WOULD NOT BE SURPRISED TO SEE THE GRAYS RIVER NEAR ROSBURG REACH MINOR FLOOD STAGE. OTHERWISE THE MOST SIGNIFICANT ISSUES ARE LIKELY TO BE MINOR URBAN FLOODING DUE TO CLOGGED STORM DRAINS AND POSSIBLY SOME SMALL STREAMS DEPENDING ON RAIN RATES. WILL ISSUE A HYDROLOGIC OUTLOOK /PDXESFPQR/ SHORTLY ADDRESSING THE SIGNIFICANT RISES AS WELL AS TO URGE THE PUBLIC TO MAKE SURE THEIR STORM DRAINS ARE CLEAR FOR THIS FIRST HEAVY RAIN EVENT OF THE SEASON. NOT TO BE LEFT OUT IN ALL THE TALK ABOUT RAIN IS THE POTENTIAL FOR WINDY CONDITIONS TO AFFECT MUCH OF OUR CWA. WHILE 850 MB WINDS ARE NOT ALL THAT IMPRESSIVE ON THE 00Z GFS...GENERALLY 45-55 KT AT THE STRONGEST FRI NIGHT AND SAT...SURFACE PRESSURE GRADIENTS THROUGH THE WILLAMETTE VALLEY ARE NOT BAD WITH 4-6 MB DEPENDING ON THE MODEL OF CHOICE. WITH ISOBARS PERPENDICULAR TO THE COAST AND WILLAMETTE VALLEY THE DOOR WILL BE OPEN FOR STRONGER WINDS ALOFT TO MIX DOWN TO THE SURFACE. COULD SEE GUSTS 30-40 MPH IN THE INLAND VALLEYS AT SOME POINT FRI NIGHT/SAT...WITH 40-50 MPH GUSTS FOR THE COAST. THESE NUMBERS ARE JUST BELOW ADVISORY AND WARNING CRITERIA RESPECTIVELY... BUT THERE STILL COULD BE SOME PROBLEMS DUE TO THE AMOUNT OF LEAVES STILL ON THE TREES. ADDITIONALLY THE WIND WILL KNOCK MORE LEAVES AND SMALL BRANCHES DOWN...FURTHER EXACERBATING THE CLOGGED STORM DRAIN ISSUES MENTIONED ABOVE. OVERALL...EXPECT VERY WET AND BLUSTERY WEATHER FRIDAY AND SATURDAY AS TRUE RAINY SEASON BEGINS FOR SOUTHWEST WASHINGTON AND NORTHWEST OREGON. WEAGLE .LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...PREVIOUS DISCUSSION BELOW...TROUGH DIVES SOUTH OVER THE WEEKEND. BEHIND THE INITIAL SURGE ON SATURDAY...THE UPPER LEVEL TROUGH AXIS MOVES ONSHORE ON SUNDAY BRINGING AN UNSTABLE AIR MASS OVER THE AREA. ALONG WITH POST FRONTAL SHOWERS WE WILL ALSO SEE SNOW LEVELS FALL THROUGH THE DAY ON SUNDAY INTO MONDAY...POSSIBLY AFFECTING THE PASSES BY MONDAY MORNING. SHOWERY UNSETTLED WEATHER CONTINUES THROUGH MONDAY STARTING TO CLEAR OUT BY TUESDAY. MIDDLE OF NEXT WEEK LOOKS DRIER AS RIDGING BUILDS OVER THE AREA BEHIND THE TROUGH PROGRESSING OFF TO THE EAST. -MCCOY && .AVIATION...WIDE RANGE OF FLIGHT CONDITIONS EARLY THIS MORNING. EXPECT MAINLY VFR AND MVFR THROUGH 19Z TODAY...WITH LOCALIZED IFR. COASTAL AREAS LIKELY TO STAY MVFR TO IFR THROUGH 00Z FRI AND THEN GO MORE IFR THEREAFTER AS WARM-FRONTAL PRECIP DEVELOPS. INLAND AREAS EXPECTED TO BE VFR WITH AREAS OF MVFR THIS AFTERNOON THROUGH THE EVENING. THERE MAY BE JUST ENOUGH SOUTH LOW-LEVEL FLOW DURING AFTER 19Z TODAY TO HELP KEEP THE AIR MASS MIXED ENOUGH TO PREVENT IFR CONDITIONS. KPDX AND APPROACHES...MVFR DEVELOPED JUST BEFORE 09Z AND SHOULD BE THE PRIMARY CATEGORY THROUGH THE MORNING HOURS. THERE WILL BE LOCAL IFR CONDITIONS ALONG WRN APPROACHES. CONDITIONS TO GRADUALLY IMPROVE INTO LOW-END VFR THIS AFTERNOON...BUT EXPECT AREAS OF MVFR CIGS...ESPECIALLY OVER WRN APPROACHES. WEISHAAR && .MARINE...SOMEWHAT OF A LULL TODAY WITH 10-15 KT SW-W WIND. WIND SPEEDS INCREASE AFTER 00Z FRI AND THU NIGHT WITH THE NEXT WARM FRONT. EXPECT SPEEDS TO REACH SMALL CRAFT ADVISORY LEVELS AROUND 12Z FRI...POSSIBLY REACHING LOW-END GALE LATE FRI MORNING. NAM AND GFS MAINTAIN 20-25 KT BOUNDARY LAYER WIND SPEEDS FRI MORNING... ALTHOUGH GFS SHOWS A NARROW BAND OF 30 KT OVER THE FAR NRN WATERS. WIND EASES A BIT FRI AFTERNOON AND EVENING...BUT INCREASES AGAIN FRI NIGHT. MUCH MORE LIKELY TO SEE GALES 06Z SAT THROUGH 00Z SUN AND AGAIN 12Z SUN THROUGH 00Z MON. HIGH PRES SPREADS INTO THE WATERS BEGINNING MON NIGHT AND HOLDS THROUGH MUCH OF NEXT WEEK. SEAS HAVE FINALLY DIPPED BELOW 10 FT EARLY THIS MORNING AND WILL REMAIN UNDER 10 FT THROUGH 12Z FRI. LATEST GUIDANCE SHOWS SEAS REACHING 10 FT OVER THE NRN WATERS FRI MORNING AND CONTINUING TO BUILD FRI THROUGH THE WEEKEND. WENT A LITTLE ABOVE ENP GUIDANCE FOR SAT/SUN DUE TO STRONGER FORECAST WIND. THUS...SEAS LIKELY TO REACH 15-17 FT THIS WEEKEND. THINK SEAS WILL STAY ABOVE 10 FT A LITTLE LONGER THAN GUIDANCE SUGGESTS...PROBABLY NOT SUBSIDING BELOW 10 FT UNTIL AT LEAST LATE TUE. WEISHAAR && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 9 AM PDT THIS MORNING. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 3 PM THIS AFTERNOON TO 8 PM PDT THIS EVENING. && $$ INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/NWSPORTLAND WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
  [top] Area Forecast Discussion National Weather Service Spokane WA 228 AM PDT THU OCT 29 2015 .SYNOPSIS... Light rain will move into the region tonight and taper off on Thursday. This break period will end on Friday as a deep fetch of Pacific moisture feeds into the region promoting widespread rain on Friday and into Saturday. Windy and gusty conditions will also develop for a damp and blustery Halloween. Unsettled conditions with occasional wet periods will continue into next week. && .DISCUSSION... Today and tonight...A shortwave trough will bring some light precipitation to the Inland Northwest today. One area of light precipitation is moving across extreme eastern WA and north ID as of 2 am. A second band is just barely holding together as it crosses the deep basin but should regain some organization as it encounters the rising terrain east of the basin. This feature will bring another round of light precipitation to the eastern half of the forecast area later this morning. The HRRR and NAM have tracked the first band well so the near term forecast is leaning heavily toward this guidance. Once the trough axis moves off to the east, scattered rain showers will continue in moist upslope flow into the Idaho Panhandle tonight while the remainder of the forecast area has a brief respite from the wet weather. Friday through Sunday...Wetter and windier conditions will begin on Friday as fire hose of an atmospheric river is aimed at the Pacific Northwest. Snow levels will remain high for Friday and Saturday as the subtropical moisture tap pushes into the forecast area. Persistent warm frontal precipitation will begin on Friday and continue into Saturday. A cold front will bring an end to the steady precip and usher in more scattered showers late Saturday. The timing of this break in the wet weather will be critical to trick-or-treaters who wish to remain dry...or at least not drenched. for Sunday, the upper trough will slide over the region with more scattered valley rain and mountain snow showers. Snow levels could fall as low as 3000 ft with mountain passes collecting some snowfall. More details on this to come in the next day or two. Storm total rainfall from Friday through Sunday will be in the one to two and a half inch range in the Idaho Panhandle and Cascades with a general one third to one half inch in the basin...except a tenth or two in the downslope deep basin area. The rising terrain east of the basin will see a half inch to and inch of rainfall. Winds will be a significant issue starting Friday and lasting through Saturday with gust potential in the well mixed warm sector potentially approaching 40 mph over exposed terrain. Winds will remain blustery through Sunday night. Monday through Thursday...The region will be under cool and unstable northerly flow as the work week begins. This will keep a chance of showers in the forecast but as the base of the trough digs south, the tap into deep Pacific moisture will be lost. Valley rain and mountain snow will be showery in nature with light amounts of precipitation compared to the weekend system. Temperatures will be near seasonal normals. /Kelch && .AVIATION... 06Z TAFS: A moist frontal band is moving into the WA/ID border region at 06Z. This is causing IFR ceilings to develop quickly over the eastern TAF sites. These cigs will persist overnight and through the morning hours before breaking up around noon. The first band of rain will move into the Panhandle over the next few hours with a break in the rain. A second band of showers will move over the Cascades and across the Basin for the remainder of the night, reaching the ID border around 15Z. RJ && .PRELIMINARY POINT TEMPS/POPS... Spokane 53 43 55 48 58 46 / 20 10 80 80 80 20 Coeur d`Alene 52 41 52 47 56 46 / 40 20 90 90 90 40 Pullman 56 43 55 47 57 46 / 20 20 80 80 80 50 Lewiston 60 46 61 52 62 50 / 20 20 80 70 70 50 Colville 52 39 52 42 54 42 / 80 10 80 80 80 20 Sandpoint 51 39 51 42 54 43 / 60 30 90 100 100 40 Kellogg 48 39 48 44 51 45 / 70 40 100 100 100 70 Moses Lake 61 44 65 48 62 47 / 40 10 50 40 50 10 Wenatchee 60 46 63 51 60 47 / 0 10 40 30 50 0 Omak 56 41 58 44 58 43 / 50 10 70 50 70 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
904 PM PDT WED OCT 28 2015 .SYNOPSIS...SCATTERED SHOWERS TONIGHT WILL DECREASE THURSDAY AS WEAK HIGH PRES BUILDS INTO THE REGION. HOWEVER...A WARM FRONT WILL SLOWLY APPROACH LATER THU NIGHT AND FRI...WITH RAIN INCREASING OVER THE REGION. A LOT OF RAIN EXPECTED SATURDAY...THEN SHOWERY AND COOLER TO START THE NOVEMBER. && .SHORT TERM...TONIGHT THROUGH SATURDAY...WATER VAPOR SATELLITE IMAGERY THIS EVENING REVEALS A SHORTWAVE TROUGH DIVING SOUTHEASTWARD ACROSS THE AREA. LARGE SCALE LIFT AHEAD OF THIS FEATURE AND COOLING TEMPERATURES ALOFT HAVE RESULTED IN NUMEROUS SHOWERS SPREADING INTO NORTHWEST OREGON AND SOUTHWEST WASHINGTON. AS THE ATMOSPHERE STABILIZES FROM THE TOP DOWN LATER TONIGHT...EXPECT SHOWERS TO BECOME INCREASINGLY CONFINED TO THE COAST RANGE AND CASCADES. AS THE LOWER ATMOSPHERE DESTABILIZES WITH LIMITED LATE OCTOBER SOLAR HEATING MIDDAY THURSDAY...THERE MAY BE A TEMPORARY INCREASE IN SHOWER ACTIVITY IN THE WILLAMETTE VALLEY AND CASCADES...BUT THESE SHOULD GRADUALLY DIMINISH AS SURFACE HIGH PRESSURE NUDGES INTO THE REGION FROM THE SOUTHWEST AND THE LOWER ATMOSPHERE DRIES OUT. OUR ATTENTION WILL THEN TURN TO A LONG FETCH OF TROPICAL MOISTURE CURRENTLY IN THE CENTER OF THE NORTH PACIFIC...WHICH WILL TAKE AIM AT THE PACIFIC NORTHWEST EARLY IN THE WEEKEND. A WARM FRONT ALONG THE LEADING EDGE OF THIS SYSTEM WILL BRING A SHOT OF HEAVIER RAIN TO MAINLY SOUTHWEST WASHINGTON. THE WILLAPA HILLS AND THE SOUTH WASHINGTON CASCADES WILL TAKE THE BRUNT OF THE HEAVIER RAIN WITH 2 TO 4 INCHES OF RAIN POSSIBLE IN 18 HOURS. THE HEAVIER RAIN AXIS WILL THEN SHIFT NORTH OF THE CWA...PRIMARILY INTO NORTHWEST WASHINGTON....LATER FRIDAY NIGHT AND EARLY SATURDAY. THIS WILL ALSO ALLOW SOME OF THE ABRUPT RIVER RISES EXPECTED FROM THIS FIRST BOUT OF RAIN TO SUBSIDE. HOWEVER...A COLD FRONT WITH STRONG DYNAMICS WILL DROP SOUTHEASTWARD AND PUSH THE THE BAND OF HEAVIER RAIN SOUTHWARD ACROSS THE AREA SATURDAY. THIS FEATURE WILL LIKELY BRING AN ADDITIONAL 0.75-1.50 INCHES OF RAIN TO THE WILLAMETTE VALLEY...AND 1 TO 3 INCHES OF RAIN TO THE CASCADES AND COAST RANGE IN A 6-12 HOUR PERIOD SATURDAY. MODELS HAVE TRENDED TOWARDS SPEEDING UP THE SOUTHWARD PROGRESS OF THIS FEATURE SO IT MAY CLEAR OUR NORTHERN ZONES INCLUDING THE PORTLAND METRO BY THE TIME TRICK-OR-TREATERS GO OUT SATURDAY EVENING. GIVEN IT IS STILL A COUPLE DAYS AWAY...CONFIDENCE IN TIMING THIS BAND OF HEAVIER RAIN IS STILL RELATIVELY LOW. /NEUMAN .LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...PREVIOUS DISCUSSION BELOW...TROUGH DIVES SOUTH OVER THE WEEKEND. BEHIND THE INITIAL SURGE ON SATURDAY...THE UPPER LEVEL TROUGH AXIS MOVES ONSHORE ON SUNDAY BRINGING AN UNSTABLE AIR MASS OVER THE AREA. ALONG WITH POST FRONTAL SHOWERS WE WILL ALSO SEE SNOW LEVELS FALL THROUGH THE DAY ON SUNDAY INTO MONDAY...POSSIBLY AFFECTING THE PASSES BY MONDAY MORNING. SHOWERY UNSETTLED WEATHER CONTINUES THROUGH MONDAY STARTING TO CLEAR OUT BY TUESDAY. MIDDLE OF NEXT WEEK LOOKS DRIER AS RIDGING BUILDS OVER THE AREA BEHIND THE TROUGH PROGRESSING OFF TO THE EAST. -MCCOY && .AVIATION...MIXED BAG OF FLIGHT CONDITIONS UNDER POST FRONTAL SHOWERS TONIGHT. MOSTLY EXPECT A MIX OF MVFR AND VFR CONDITIONS... WITH A FEW POCKETS OF IFR VIS AND/OR CIGS. EXPECT WEAKLY ONSHORE LOW LEVEL FLOW AND A STABILIZING AIR MASS TO BRING GOOD CHANCE OF RETURNING MVFR AND IFR STRATUS TO THE COAST LATE THIS EVENING. WILL ALSO SEE MORE WIDESPREAD MVFR STRATUS RETURNING INLAND LATER TONIGHT...CONTINUING THROUGH DAYBREAK BUT THEN GRADUALLY LIFTING AND TRENDING TOWARDS LOWER VFR CIGS. KPDX AND APPROACHES...MAINLY LOW-END VFR WITH CIGS AROUND 4000 FT THROUGH 06Z-08Z THU. OCCASIONAL SHOWERS WILL BRING LOW MVFR CIGS AT TIME...THEN WITH STABILIZING AIR MASS AND LIGHT ONSHORE FLOW OVERNIGHT...EXPECT MORE SOLID MVFR STRATUS TO REDEVELOP LATE TONIGHT THROUGH EARLY THURSDAY. CULLEN/27 && .MARINE...NW WINDS 10-15 KTS WILL CONTINUE OVERNIGHT BEHIND THE COLD FRONT. SEAS DROPPED TO NEAR 8 FT THIS AFTERNOON BUT HAVE BOUNCED BACK TO 10 FT THIS EVENING. EXPECT SEAS TO FINALLY SUBSIDE TO LESS THAN 10 FT CLOSER TO MIDNIGHT. THEREFORE...THE CURRENT ADVISORY FOR HAZARDOUS SEAS REMAINS IN EFFECT THROUGH TONIGHT. AFTER A BRIEF LULL AND RELATIVELY BENIGN CONDITIONS EARLY THURSDAY...A STRONGER SYSTEM WILL BRING A RETURN OF BUILDING SEAS AND AT LEAST SMALL CRAFT ADVISORY STRENGTH WINDS FOR THE END OF THE WEEK INTO THE WEEKEND. STILL SOME UNCERTAINTY IN HOW STRONG THE WINDS WILL BE...BUT CONFIDENCE IS INCREASING IN A PERIOD OF GALE FORCE GUSTS...AND PERHAPS SUSTAINED GALES...ON SATURDAY. SUBSEQUENT DISTURBANCES COULD BRING PERIODS OF GALE GUSTS INTO EARLY NEXT WEEK. SEAS WILL ALSO REBUILD GREATER THAN 10 FT BY LATER FRIDAY AND REMAIN ELEVATED THROUGH THE WEEKEND...LIKELY PEAKING IN THE NEIGHBORHOOD OF 14-17 FT SUNDAY AND REMAINING GREATER THAN 10 FT THROUGH THE FIRST PORTION OF NEXT WEEK. CULLEN && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 11 PM PDT THIS EVENING...AND AGAIN FROM 4 AM TO 9 AM PDT THURSDAY. && $$ INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/NWSPORTLAND WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion National Weather Service Spokane WA 513 PM PDT WED OCT 28 2015 .SYNOPSIS... Light rain will move into the region tonight and taper off on Thursday. This break period will end on Friday as a deep fetch of Pacific moisture feeds into the region promoting widespread rain on Friday and into Saturday. Windy and gusty conditions will also develop for a damp and blustery Halloween. Unsettled conditions with occasional wet periods will continue into next week. && .DISCUSSION... Quick update to the forecast for tonight. Radar shows the anticipated precipitation is moving across the Basin. Yakima, Ellensburg, Wenatchee, and Omak have all measured a few hundredths of an inch so far. Best area of rain looks to be moving into the Basin between Ephrata and Tri-Cities. Radar trends agree for the most part with the NAM and HRRR models, although the HRRR does seem a tad slow. Light steady rain should reach the WA/ID border cities around 10 or 11 pm with sprinkles possible before then. Rain will only last for a few hours. Low clouds and some fog will form in the wake of the rain, east of a Republic-to-Lewiston line, and these will persist into Thursday morning. RJ && .AVIATION... 00Z TAFS: A weak but moist front will move over the region this evening and overnight. This will bring light rain to all of the TAF sites. Only the KGEG/KSFF/KCOE/KPUW sites are expected to have IFR weather from this. This will begin as the rain ends in the middle of the night and continue through the morning hours in the form of a low stratus cloud deck, which should dissipate around noon. There are currently bands of showers over western WA/OR and some of these may be able to survive the trip across the Cascades and bring renewed precipitation chances in the morning. But these typically don`t amount to much so they were left out of the TAFs. RJ && .PREV DISCUSSION... /issued 438 PM PDT WED OCT 28 2015/ SYNOPSIS... Light rain will move into the region tonight and taper off on Thursday. This break period will end on Friday as a deep fetch of Pacific moisture feeds into the region promoting widespread rain on Friday and into Saturday. Windy and gusty conditions will also develop for a damp and blustery Halloween. Unsettled conditions with occasional wet periods will continue into next week. Light rain will move into the region tonight and taper off on Thursday. This break period will end on Friday as a deep fetch of Pacific moisture feeds into the region promoting widespread rain on Friday and into Saturday. Windy and gusty conditions will also develop for a damp and blustery Halloween. Unsettled conditions with occasional wet periods will continue into next week. DISCUSSION... Tonight and Thursday...The pattern change is underway with the gradual de-amplification of the long-wave ridge and it being replaced with a more progressive zonal flow. The weak occluded frontal zone currently associated with a north to south oriented band of precipitation working its way from west to east is weakening some as it moves through the forecast area. The weakening is more or less justifying the rather light precipitation amounts in the forecast coupled with the high pops. Given the progressive nature of the forecast for the next 24 hours forecast temperatures remain on a bit on the warm side of climo for this time of year. /Pelatti Thursday night through Saturday night...A wet and windy autumnal pattern is shaping up for this period featuring a good hosing from a subtropical atmospheric river enhancing over a series of transient fronts Friday and Saturday. Snow levels will remain in the 6000 foot range as an air mass able to support this 1 inch or so PWAT stream will necessarily be warmer than average and promote warmer than average surface temperatures through the period. Storm total rainfall from Friday through Saturday night...according to a blend of the suite of current model guidance...suggests one to two inches in the Idaho Panhandle and Cascades with a general one third to 1/2 inch or more in the basin...except a tenth or so in the downslope deep basin area. Thursday night will witness the departure of the initial outriding short wave with decreasing showers mainly over the Idaho Panhandle. Friday morning will feature a moist air mass with light winds...and despite mid level cloud cover there is a good chance of at least patchy fog in valleys. Friday the incoming atmospheric river will arrive and enhance isentropically over the first warm front providing some substantial rainfall and high mountain snow for most of the region. Winds will become breezy out of the southwest as this initial warm front passes through. The fetch will become more favorably directed and established Friday night and Saturday with another warm front and round of sustained stratiform rain...but the deep basin zones will experience a minor rain shadow effect in the overall fast westerly flow regime driving the fetch into the region. Winds will be a significant issue starting Friday and lasting through Saturday with gust potential in the well mixed warm sector potentially approaching 40 mph over exposed terrain. A weak cold occluded front will round out the frontal parade during the day Saturday. The all important Trick-or-Treat period for the youngsters may occur as the air mass dries out after this FROPA over much of the area...showery but not a total rain out...but still quite windy and blustery over the region. /Fugazzi AVIATION... 00Z TAFS: A weak but moist front will move over the region this evening and overnight. This will bring light rain to all of the TAF sites. Only the KGEG/KSFF/KCOE/KPUW sites are expected to have IFR weather from this. This will begin as the rain ends in the middle of the night and continue through the morning hours in the form of a low stratus cloud deck, which should dissipate around noon. There are currently bands of showers over western WA/OR and some of these may be able to survive the trip across the Cascades and bring renewed precipitation chances in the morning. But these typically don`t amount to much so they were left out of the TAFs. RJ 00Z TAFS: A weak but moist front will move over the region this evening and overnight. This will bring light rain to all of the TAF sites. Only the KGEG/KSFF/KCOE/KPUW sites are expected to have IFR weather from this. This will begin as the rain ends in the middle of the night and continue through the morning hours in the form of a low stratus cloud deck, which should dissipate around noon. There are currently bands of showers over western WA/OR and some of these may be able to survive the trip across the Cascades and bring renewed precipitation chances in the morning. But these typically don`t amount to much so they were left out of the TAFs. RJ && .PRELIMINARY POINT TEMPS/POPS... Spokane 43 54 42 56 47 57 / 100 40 10 80 80 80 Coeur d`Alene 43 52 40 52 45 55 / 90 70 20 80 90 90 Pullman 43 55 43 55 46 56 / 100 60 20 80 80 80 Lewiston 46 59 44 61 50 62 / 80 40 20 60 70 70 Colville 42 54 40 53 43 54 / 90 50 10 80 80 70 Sandpoint 42 50 40 52 42 52 / 90 80 30 90 100 100 Kellogg 42 49 39 48 43 51 / 100 80 40 100 100 100 Moses Lake 43 62 44 65 48 62 / 100 20 10 50 40 50 Wenatchee 44 61 43 63 49 61 / 60 20 10 40 30 50 Omak 40 58 39 58 43 57 / 60 20 10 70 50 70 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS TUCSON AZ
500 AM MST THU OCT 29 2015 .SYNOPSIS...A LOW PRESSURE SYSTEM WILL BRING A PERIOD OF SHOWERS THROUGH FRIDAY WITH A DUSTING TO A FEW INCHES OF SNOW IN THE HIGHEST MOUNTAIN LOCATIONS. SOME OF THE COLDEST LOW TEMPERATURES OF THE SEASON ARE THEN EXPECTED THIS WEEKEND. DRY CONDITIONS SATURDAY THROUGH MONDAY BEFORE ANOTHER SYSTEM BRINGS A SLIGHT CHANCE OF SHOWERS...GUSTY WINDS AND COOLER TEMPERATURES BY THE MIDDLE OF NEXT WEEK. && .UPDATE...ADDED THE MENTION OF THUNDER TO OUR GRIDS FOR THE REST OF THE MORNING BASED ON CURRENT LIGHTNING OBSERVATIONS. NO OTHER CHANGES MADE AT THIS TIME. && .DISCUSSION...EARLY-MORNING WATER VAPOR LOOPS SHOW MID AND HIGH LEVEL MOISTURE CONTINUING TO STREAM INTO THE REGION IN ADVANCE OF A SHARPENING TROUGH TO OUR WEST. IR IMAGERY REVEALS AN ENHANCED BAND OF GRADUALLY COOLING CLOUD TOPS CURRENTLY PROGRESSING THROUGH CENTRAL PIMA AND PINAL COUNTIES WHICH APPEAR TO BE RIGHT ALONG AND AHEAD OF A 700 MB TROUGH AXIS/WIND SHIFT PER RECENT RAP ANALYSES. THERE HAVE ACTUALLY BEEN A FEW LIGHTNING STRIKES WITH THIS EXPANDING AREA OF PRECIPITATION/CLOUD COVER. AS FAR AS OUR FORECAST IS CONCERNED...CURRENTLY ANTICIPATE A GRADUAL INCREASE IN SHOWER/EMBEDDED THUNDERSTORMS WITH AN INITIAL FOCUS FROM ROUGHLY EAST AND NORTH OF TUCSON THROUGH THE MORNING AS THE AFOREMENTIONED 700 MB TROUGH SWINGS EASTWARD. THEN...AS THE LARGER MID AND UPPER-LEVEL TROUGH AXIS TAKES ON MORE OF A NEUTRAL TILT THROUGH THE AFTERNOON...HEIGHTS WILL FALL QUICKLY AND THE HIGH-LEVEL FLOW WILL BECOME MORE DIFFLUENT ALLOWING FOR PRECIPITATION COVERAGE TO EXPAND ACROSS MUCH OF THE CWA...ALTHOUGH BELIEVE THE HIGHEST PRECIP CHANCES WILL REMAIN ACROSS OUR NORTHERN AND EASTERN ZONES AMIDST THE BETTER DIFFLUENT FLOW. PRECIPITATION CHANCES WILL CONTINUE THROUGH TONIGHT AND INTO FRIDAY MORNING AS THE TROUGH AXIS SWEEPS THROUGH THE AREA. SNOW LEVELS SHOULD FALL TO THEIR LOWEST LEVELS AROUND THIS TIME...BUT ALL INDICATIONS CONTINUE TO POINT TO THEM REMAINING ABOVE 8500 FEET OR SO WITH THE PRECIP AMOUNTS SUPPORTING GENERALLY ONE TO FOUR INCH AMOUNTS IN THESE LOCATIONS. THEREAFTER...ANTICIPATING A FAIRLY QUICK WEST-TO-EAST DRYING TREND DURING THE DAY FRIDAY AS THIS PROGRESSIVE TROUGH MOVES QUICKLY INTO NEW MEXICO. AS SUCH...MADE ADJUSTMENTS TO THE INHERITED FORECAST TO MORE QUICKLY DECREASE POPS FRIDAY AFTERNOON AND OVERNIGHT INTO SATURDAY BUT NOTE THAT THIS MAY STILL BE A BIT TOO SLOW. FAIRLY IDEAL RADIATIONAL COOLING CONDITIONS THEN LOOK TO BE IN PLACE OVERNIGHT FRIDAY AND SATURDAY. AS A RESULT...FREEZING OR NEAR- FREEZING LOW TEMPERATURES ARE A CONCERN IN OUR FAVORED VALLEY LOCATIONS EAST OF TUCSON WITH SATURDAY LOOKING LIKE TO COLDEST NIGHT AT THIS TIME. TEMPERATURES WILL REBOUND QUICKLY SATURDAY AND MONDAY AS SHORTWAVE RIDGING TAKES CONTROL OF OUR WEATHER...ALBEIT VERY BRIEFLY. BOTH THE DETERMINISTIC AND ENSEMBLE GFS/ECMWF ARE IN FAIR AGREEMENT THAT ANOTHER TROUGH WILL DIVE INTO THE GREAT BASIN AROUND TUESDAY. EARLY INDICATIONS ARE THAT THIS SYSTEM MAY BRING A PERIOD OF FAIRLY STRONG SOUTHWESTERLY WINDS IN ADDITION TO THE RISK FOR SHOWERS. && .AVIATION...VALID THRU 30/12Z. SCATTERED TO NUMEROUS -SHRA WILL OCCUR MAINLY FROM KTUS VICINITY EAST TO THE NEW MEXICO BORDER INTO EARLY FRIDAY MORNING. ISOLATED -TSRA WILL BE POSSIBLE...ESPECIALLY THIS AFTERNOON AND EVENING. ONLY A SLIGHT CHANCE OF -SHRA EXISTS ACROSS WESTERN PIMA COUNTY WEST OF KTUS. EXPECT MVFR CONDITIONS THROUGH THE PERIOD...PARTICULARLY NEAR THE MOUNTAINS. OTHERWISE...CLOUD DECKS WILL MAINLY RANGE FROM 8K-12K FT MSL. SURFACE WIND THIS AFTERNOON WILL BE WLY/SWLY AT 10-16 KTS WITH GUSTS TO 25 KTS. SURFACE WIND WILL BE LESS THAN 10 KTS AT OTHER TIMES. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...SCATTERED TO NUMEROUS SHOWERS WILL OCCUR MAINLY FROM TUCSON EAST TO THE NEW MEXICO BORDER THROUGH TONIGHT. ISOLATED THUNDERSTORMS MAY ALSO OCCUR PARTICULARLY THIS AFTERNOON AND EVENING. A SLIGHT CHANCE OF SHOWERS EXISTS ACROSS WESTERN PIMA COUNTY INTO TONIGHT. RAIN CHANCES WILL DECREASE FROM WEST TO EAST FRIDAY FOLLOWED BY A FEW LINGERING SHOWERS NEAR THE NEW MEXICO BORDER FRIDAY EVENING. DRY CONDITIONS WILL THEN PREVAIL LATE FRIDAY NIGHT THROUGH MONDAY NIGHT. A SLIGHT CHANCE OF SHOWERS WILL RETURN MAINLY NEAR THE MOUNTAINS TUESDAY INTO WEDNESDAY. 20-FOOT WINDS THIS AFTERNOON WILL BE WEST AT 10 TO 15 MPH FOLLOWED BY GENERALLY LIGHT TERRAIN DRIVEN WINDS FRIDAY INTO SUNDAY. EXPECT GUSTY SOUTH TO SOUTHWEST WINDS MONDAY INTO WEDNESDAY DURING THE AFTERNOON HOURS. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...CARLAW AVIATION/FIRE WEATHER...FRANCIS VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS TUCSON AZ
417 AM MST THU OCT 29 2015 .SYNOPSIS...A LOW PRESSURE SYSTEM WILL BRING A PERIOD OF SHOWERS THROUGH FRIDAY WITH A DUSTING TO A FEW INCHES OF SNOW IN THE HIGHEST MOUNTAIN LOCATIONS. SOME OF THE COLDEST LOW TEMPERATURES OF THE SEASON ARE THEN EXPECTED THIS WEEKEND. DRY CONDITIONS SATURDAY THROUGH MONDAY BEFORE ANOTHER SYSTEM BRINGS A SLIGHT CHANCE OF SHOWERS...GUSTY WINDS AND COOLER TEMPERATURES BY THE MIDDLE OF NEXT WEEK. && .DISCUSSION...EARLY-MORNING WATER VAPOR LOOPS SHOW MID AND HIGH LEVEL MOISTURE CONTINUING TO STREAM INTO THE REGION IN ADVANCE OF A SHARPENING TROUGH TO OUR WEST. IR IMAGERY REVEALS AN ENHANCED BAND OF GRADUALLY COOLING CLOUD TOPS CURRENTLY PROGRESSING THROUGH CENTRAL PIMA AND PINAL COUNTIES WHICH APPEAR TO BE RIGHT ALONG AND AHEAD OF A 700 MB TROUGH AXIS/WIND SHIFT PER RECENT RAP ANALYSES. THERE HAVE ACTUALLY BEEN A FEW LIGHTNING STRIKES WITH THIS EXPANDING AREA OF PRECIPITATION/CLOUD COVER. AS FAR AS OUR FORECAST IS CONCERNED...CURRENTLY ANTICIPATE A GRADUAL INCREASE IN SHOWER/EMBEDDED THUNDERSTORMS WITH AN INITIAL FOCUS FROM ROUGHLY EAST AND NORTH OF TUCSON THROUGH THE MORNING AS THE AFOREMENTIONED 700 MB TROUGH SWINGS EASTWARD. THEN...AS THE LARGER MID AND UPPER-LEVEL TROUGH AXIS TAKES ON MORE OF A NEUTRAL TILT THROUGH THE AFTERNOON...HEIGHTS WILL FALL QUICKLY AND THE HIGH-LEVEL FLOW WILL BECOME MORE DIFFLUENT ALLOWING FOR PRECIPITATION COVERAGE TO EXPAND ACROSS MUCH OF THE CWA...ALTHOUGH BELIEVE THE HIGHEST PRECIP CHANCES WILL REMAIN ACROSS OUR NORTHERN AND EASTERN ZONES AMIDST THE BETTER DIFFLUENT FLOW. PRECIPITATION CHANCES WILL CONTINUE THROUGH TONIGHT AND INTO FRIDAY MORNING AS THE TROUGH AXIS SWEEPS THROUGH THE AREA. SNOW LEVELS SHOULD FALL TO THEIR LOWEST LEVELS AROUND THIS TIME...BUT ALL INDICATIONS CONTINUE TO POINT TO THEM REMAINING ABOVE 8500 FEET OR SO WITH THE PRECIP AMOUNTS SUPPORTING GENERALLY ONE TO FOUR INCH AMOUNTS IN THESE LOCATIONS. THEREAFTER...ANTICIPATING A FAIRLY QUICK WEST-TO-EAST DRYING TREND DURING THE DAY FRIDAY AS THIS PROGRESSIVE TROUGH MOVES QUICKLY INTO NEW MEXICO. AS SUCH...MADE ADJUSTMENTS TO THE INHERITED FORECAST TO MORE QUICKLY DECREASE POPS FRIDAY AFTERNOON AND OVERNIGHT INTO SATURDAY BUT NOTE THAT THIS MAY STILL BE A BIT TOO SLOW. FAIRLY IDEAL RADIATIONAL COOLING CONDITIONS THEN LOOK TO BE IN PLACE OVERNIGHT FRIDAY AND SATURDAY. AS A RESULT...FREEZING OR NEAR- FREEZING LOW TEMPERATURES ARE A CONCERN IN OUR FAVORED VALLEY LOCATIONS EAST OF TUCSON WITH SATURDAY LOOKING LIKE TO COLDEST NIGHT AT THIS TIME. TEMPERATURES WILL REBOUND QUICKLY SATURDAY AND MONDAY AS SHORTWAVE RIDGING TAKES CONTROL OF OUR WEATHER...ALBEIT VERY BRIEFLY. BOTH THE DETERMINISTIC AND ENSEMBLE GFS/ECMWF ARE IN FAIR AGREEMENT THAT ANOTHER TROUGH WILL DIVE INTO THE GREAT BASIN AROUND TUESDAY. EARLY INDICATIONS ARE THAT THIS SYSTEM MAY BRING A PERIOD OF FAIRLY STRONG SOUTHWESTERLY WINDS IN ADDITION TO THE RISK FOR SHOWERS. && .AVIATION...VALID THRU 30/12Z. SCATTERED TO NUMEROUS -SHRA WILL OCCUR MAINLY FROM KTUS VICINITY EAST TO THE NEW MEXICO BORDER INTO EARLY FRIDAY MORNING. ISOLATED -TSRA WILL BE POSSIBLE...ESPECIALLY THIS AFTERNOON AND EVENING. ONLY A SLIGHT CHANCE OF -SHRA EXISTS ACROSS WESTERN PIMA COUNTY WEST OF KTUS. EXPECT MVFR CONDITIONS THROUGH THE PERIOD...PARTICULARLY NEAR THE MOUNTAINS. OTHERWISE...CLOUD DECKS WILL MAINLY RANGE FROM 8K-12K FT MSL. SURFACE WIND THIS AFTERNOON WILL BE WLY/SWLY AT 10-16 KTS WITH GUSTS TO 25 KTS. SURFACE WIND WILL BE LESS THAN 10 KTS AT OTHER TIMES. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...SCATTERED TO NUMEROUS SHOWERS WILL OCCUR MAINLY FROM TUCSON EAST TO THE NEW MEXICO BORDER THROUGH TONIGHT. ISOLATED THUNDERSTORMS MAY ALSO OCCUR PARTICULARLY THIS AFTERNOON AND EVENING. A SLIGHT CHANCE OF SHOWERS EXISTS ACROSS WESTERN PIMA COUNTY INTO TONIGHT. RAIN CHANCES WILL DECREASE FROM WEST TO EAST FRIDAY FOLLOWED BY A FEW LINGERING SHOWERS NEAR THE NEW MEXICO BORDER FRIDAY EVENING. DRY CONDITIONS WILL THEN PREVAIL LATE FRIDAY NIGHT THROUGH MONDAY NIGHT. A SLIGHT CHANCE OF SHOWERS WILL RETURN MAINLY NEAR THE MOUNTAINS TUESDAY INTO WEDNESDAY. 20-FOOT WINDS THIS AFTERNOON WILL BE WEST AT 10 TO 15 MPH FOLLOWED BY GENERALLY LIGHT TERRAIN DRIVEN WINDS FRIDAY INTO SUNDAY. EXPECT GUSTY SOUTH TO SOUTHWEST WINDS MONDAY INTO WEDNESDAY DURING THE AFTERNOON HOURS. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...CARLAW AVIATION/FIRE WEATHER...FRANCIS VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
952 AM CDT THU OCT 29 2015 .UPDATE... ISSUED AT 951 AM CDT THU OCT 29 2015 Stratocumulus deck continues to sink southward this morning, with the leading edge roughly from Quincy to Lincoln to Watseka. RAP model humidity guidance suggesting this could make it as far south as about I-70, before a clearing push begins from the southwest late this afternoon. Winds already gusting up to near 30 mph in much of the CWA, with the HRRR showing the gustiness lasting through mid afternoon before some tapering begins. Existing forecast was largely on track and only required some minor tweaks. The worded forecasts were updated to reflect the latest sky trends. && .SHORT TERM...(Today) ISSUED AT 326 AM CDT THU OCT 29 2015 Unseasonably deep 521dm 500mb low continues to spin over Lake Michigan this morning, while a significant vorticity max rotates southward around the parent low across Minnesota. Low cloudiness associated with the vort lobe will gradually spill southward today, impacting the northern half of the KILX CWA. NAM 1000-850mb RH field is handling the current cloud cover quite well, so will follow this parameter closely for the sky cover forecast today. As a result, am expecting mostly clear skies across the board at dawn with overcast conditions developing along/north of the I-74 corridor toward midday into the afternoon hours. Will also be a windy day as pressure gradient between low over the Great Lakes and high building into the Plains remains tight. Forecast soundings and numeric guidance both suggest sustained winds of 15-20mph with gusts to between 25 and 30mph at times. Due to continued CAA, high temperatures will remain well below normal...with readings ranging from the upper 40s far north where cloud cover will be prevalent to the middle 50s along/south of I-70 where skies will remain sunny. .LONG TERM...(Tonight through Wednesday) ISSUED AT 326 AM CDT THU OCT 29 2015 High pressure will build into the Midwest tonight, providing clearing skies and diminishing winds. Overnight lows will dip into the lower to middle 30s. After a sunny/cool day on Friday with highs mainly in the 50s, an approaching northern stream short-wave will spread clouds and showers back into the area Friday night into Saturday. Models are in good agreement with the timing of this feature and the overall QPF...with rainfall totals generally around half an inch. Given presence of an initially dry airmass associated with the departing high, will continue to keep Friday evening dry. However, as stronger upper dynamics approach from the west and mid/low-level airmass moistens, will introduce likely PoPs along/west of I-55 and chance PoPs further east across the remainder of the CWA after midnight. Best rain chances are still on target for Saturday, when widespread showers are expected. Upper wave is progressive and will quickly push off to the east Saturday night. Will linger showers into Saturday evening, but will dry things out from west to east overnight. Models have come into better agreement concerning evolution and track of upper low initially in place over the Desert Southwest this weekend. Previous runs had shown a highly amplified closed low, but the 00z Oct 29 model suite now indicates a much weaker open feature that ejects eastward more quickly. Both the GFS and ECMWF take this wave into the Tennessee River Valley Sunday night into Monday, keeping any precip well S/SE of Illinois. Meanwhile, the GEM continues to be the odd model out by bringing the wave much further north and spreading rain into the CWA on Monday. Given clear trend toward a weaker/faster/more southern solution, have rejected the GEM in favor of the GFS/ECMWF consensus. As such, have gone with a dry forecast Sunday through Tuesday with a steady warming trend. As has been the case for the past several days, models continue to show rising upper heights across the region early next week. 850mb temps on both the GFS and ECMWF are progged to reach the 14-16C range by Tuesday and Wednesday, supporting highs into the 70s. GFS tries to bring moisture northward in the WAA regime as early as Wednesday, but think this is too aggressive, especially given the fact that the ECMWF holds any precip off until Friday at the earliest. As a result, will continue the dry forecast through Wednesday. && .AVIATION...(For the 12Z TAFS through 12Z Friday morning) ISSUED AT 626 AM CDT THU OCT 29 2015 Mostly clear skies with steady WSW winds 12-15 kts across central IL terminals this morning. An area of low cloud over northern IL/eastern IA containing primarily MVFR ceilings is spreading southeastward and will begin to affect central IL terminals starting 14Z-16Z through most of the day. Winds associated with this feature will bring W winds 15-20 kts and gusts 24 to 28 kts through most of the late morning and afternoon. High pressure building into the region late in the day will cause winds to decrease and cloud cover to decrease after 00Z. && .ILX Watches/Warnings/Advisories... NONE. && $$ UPDATE...Geelhart SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Onton
AREA FORECAST DISCUSSION
NWS CARIBOU ME
938 AM EDT THU OCT 29 2015 .SYNOPSIS... SOAKING RAIN AND GUSTY WINDS WILL PERSIST TODAY WHILE STRONG LOW PRESSURE TRACKS NORTHWEST OF MAINE. COLDER WEATHER RETURNS FRIDAY WITH GUSTY NORTHWEST WINDS. HIGH PRESSURE WILL MOVE OVER THE REGION ON SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... 935 AM UPDATE...CURRENT HEADLINES REMAIN IN PLACE THIS MORNING. PLEASE SEE THE TIDAL/COASTAL SECTION BELOW FOR DETAILS ON THE COASTAL FLOOD ADVISORY. OTHER CONCERNS CONTINUE TO BE HIGH WINDS, ESPECIALLY DOWNEAST. WE HAVE HAD REPORTS OF GUSTS OF 50 MPH OR MORE, ESPECIALLY ALONG THE COAST. WINDS SHOULD AT WORST REMAIN STEADY OVER THE NEXT HOUR OR SO, BUT EXPECT AN OVERALL DECREASE IN WIND SPEEDS AS WE GO THROUGH THE MORNING HOURS AND THE LOW LEVEL JET EXITS. WE HAVE ALSO HAD REPORTS OF POWER OUTAGES AND SOME TREES/BRANCHES DOWN. THE HIGH WIND WARNING THEREFORE REMAINS IN EFFECT. OTHERWISE, THE HEAVIEST RAIN HAS MAINLY EXITED OUR AREA, ALTHOUGH DOWNEAST CONTINUES TO SEE A BATCH OF HEAVY PRECIPITATION AT THIS TIME. OUTSIDE OF THIS RAIN, THERE ARE SCATTERED SHOWERS OVER MUCH OF THE REST OF THE STATE. ALL THIS PRECIPITATION WILL COME TO AN END AS THE BULK OF THE WARM AIR ADVECTION LIFTS INTO CANADA. EXPECT WE WILL SEE A BRIEF BREAK IN THE PRECIPITATION THEREAFTER, MAINLY EARLY-MID AFTERNOON. SOME SUN COULD EVEN BREAK THROUGH, ESPECIALLY IN THE CENTRAL HIGHLANDS SOUTHWARD TO THE COAST. THE CONCERN THEN BECOMES THE COLD FRONT WHICH WILL APPROACH FROM THE WEST LATE THIS AFTERNOON INTO THE EVENING. THERE WILL BE SOME INSTABILITY AVAILABLE OUT AHEAD OF THIS FEATURE, ESPECIALLY IF WE CAN GET SOME CLEARING. TEMPERATURES WILL BE IN THE 60S, WITH DEWPOINTS 55-60 OR SO. AS SUCH, EXPECT WE COULD SEE CONVECTION ALONG THE FRONT; INDEED, THE HRRR SHOWS A SQUALL LINE CROSSING NORTHERN MAINE LATER TODAY. ALTHOUGH THE LOW LEVEL JET WILL HAVE PASSED, THERE WILL STILL BE PLENTY OF FLOW ALOFT FOR WINDS TO MIX DOWN IN ANY THUNDERSTORMS. BRIEF HEAVY RAIN WILL BE A POSSIBILITY AS WELL. PREVIOUS DISCUSSION...INTENSE LOW PRESSURE OVER THE WESTERN GREAT LAKES WILL MOVE NORTHEAST INTO CANADA TODAY. THIS SYSTEM IS EXPECTED TO PRODUCE STRONG SOUTHERLY WINDS...HEAVY RAIN ALONG WITH SOME ISOLATED THUNDERSTORMS. A COLD FRONT WILL MOVE THROUGH LATER TODAY WITH A MUCH COLDER AIR MASS MOVING IN BEHIND THE FRONT THIS TONIGHT. COLD ADVECTION WILL CONTINUE TONIGHT ALONG WITH AN UPPER LEVEL LOW PRESSURE SYSTEM. THE UPPER LOW WILL PRODUCE SOME SHOWERS EARLY TONIGHT WITH SNOW SHOWERS LATER TONIGHT AS COLDER AIR MOVES IN. FOR MAXIMUM TEMPERATURE WILL USE THE CONSENSUS BLEND AND FOR MINIMUM TEMPERATURE WILL USE THE BIAS CONSENSUS MOS BASED ON VERIFICATION LAST FOUR PERIODS. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... MAIN CONCERN IN THIS TERM WILL BE THE WINDS FOR FRIDAY. MUCH COLDER AIR WILL BE MOVING INTO THE REGION ON FRIDAY W/NW WINDS KICKING IN. MODEL SOUNDINGS SHOW INVERTED V W/MOISTURE LIMITED BETWEEN 850-700MBS. MOMENTUM TRANSFER INDICATES WIND GUST POTENTIAL OF 35 TO 40 MPH DURING THE DAY W/THE HIGHEST GUSTS OVER THE HIGHER TERRAIN. THE NAM AND GFS BOTH SUPPORT THIS POTENTIAL. GIVEN THAT SUNSHINE WILL BE AVAILABLE EARLY TO ALLOW FOR SOME HEATING IN THE BLYR, GUSTY WINDS ARE POSSIBLE. THEREFORE, DECIDED TO BUMP THE GUSTS FOR FRIDAY. CAA UNDERWAY COMBINED W/THE WINDS WILL MAKE IT FOR A COLD DAY W/DAYTIME MAXES STRUGGLING TO GET OUT OF THE LOWER 40S ACROSS THE NORTH AND WEST. CENTRAL AND AND DOWNEAST AREAS SHOULD SEE SOME DOWNSLOPING TO ALLOW FOR UPPER 40S TO LOWER 50S. THE WINDS WILL SUBSIDE FRIDAY NIGHT AS THE GRADIENT RELAXES AND SKIES CLEAR OUT. WINDS LOOK LIKE AS THOUGH THEY WILL STAY UP ENOUGH TO ALLOW FOR SOME MIXING IN THE BLYR. THIS IN TURN WILL KEEP OVERNIGHT TEMPERATURES FROM BOTTOMING OUT BELOW THE MID 20WS AS IT LOOKS ATTM. HIGH PRES IS FORECAST TO RIDGE ACROSS THE CWA FROM THE S ON SATURDAY W/A CONTINUED CHILLY AIRMASS. DAYTIME MAXES ARE EXPECTED TO BE IN THE LOW TO MID 40S ACROSS THE NORTHERN 1/2 OF THE CWA W/UPPER 40S TO AROUND 50 CENTRAL AND DOWNEAST. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... A RATHER ACTIVE PATTERN TO CONTINUE FOR THIS TERM. HIGH PRES WILL PASS OFF TO THE E ON SATURDAY NIGHT WHICH WILL ALLOW FOR A RETURN FLOW TO SET UP IN ADVANCE OF AN APPROACHING FRONTAL SYSTEM. OVERNIGHT TEMPERATURES WILL DROP OFF QUICKLY SATURDAY EVENING AND THEN SHOULD LEVEL OFF AS CLOUDS MOVE AFTER MIDNIGHT. SUNDAY WILL SEE CLOUDS AND A ROUND OF SHOWERS MOVING INTO THE CWA AS LOW PRES MOVES THROUGH QUEBEC BRINGING A FRONTAL BOUNDARY ACROSS THE REGION. DECIDED TO BRING POPS UP TO 70% ACROSS THE NORTHERN 1/2 OF THE CWA AND STAYED W/CHANCE POPS(40-50%) FOR THE REST OF THE REGION. THIS SYSTEM IS A FAST MOVER AND SHOWERS SHOULD END AFTER MIDNIGHT. A SLIGHT COOLDOWN IS FORECAST ON MONDAY BUT TEMPERATURES ABOVE NORMAL FOR EARLY NOVEMBER. HIGH PRES IS FORECAST TO SLIDE S OF THE CWA ON TUESDAY W/DRY WEATHER. && .AVIATION /13Z THURSDAY THROUGH MONDAY/... NEAR TERM: EXPECT IFR CONDITIONS TODAY THEN IMPROVING TO VFR CONDITIONS LATER TONIGHT. SHORT TERM: MVFR CIGS FRIDAY MORNING ACROSS THE NORTHERN TERMINALS. OTHERWISE, VFR INTO SATURDAY FOR ALL TERMINALS. CONDITIONS ARE EXPECTED TO DROP TO MVFR ON SUNDAY W/SOME SHRA POSSIBLE. && .MARINE... NEAR TERM: WILL USE THE NAM12 FOR SUSTAINED WINDS TODAY AND TONIGHT. WILL KEEP GALE WARNING IN PLACE INTO THIS AFTERNOON. WINDS MAY DIMINISH LATER TODAY THEN INCREASE TONIGHT IN COLD ADVECTION BEHIND COLD FRONT. FOR WAVES: A SOUTHEASTERLY FETCH IS CURRENTLY DEVELOPING FROM THE NEW ENGLAND COAST SOUTHWARD.THIS FETCH WILL CONTINUE TO BUILD INTO EARLY AFTERNOON THEN WILL BE BROKEN UP BY WIND SHIFT TOWARDS EVENING. EXPECT MAXIMUM WAVE HEIGHTS TO BUILD TO AROUND 18 FEET/10-12 SECONDS BY THIS AFTERNOON. WILL USE NEAR SHORE WAVE MODEL WITH WAVE WATCH III FORCING TO POPULATE WAVE GRIDS. SHORT TERM: A STRONG SMALL CRAFT ADVISORY EXPECTED FOR SATURDAY W/NW WINDS KICKING IN. SUSTAINED WINDS OF 20-25 KT W/GUSTS TO AROUND 30. GUSTS COULD APPROACH 35 KTS FOR A FEW HRS ON FRIDAY W/THE COLD FRONT PASSAGE. WAVE HEIGHTS WILL BEGIN TO SUBSIDE DURING THE DAY. CONDITIONS ARE FORECAST TO IMPROVE FRIDAY NIGHT INTO SATURDAY W/WINDS DROPPING BELOW 20S KTS AND WAVE HEIGHTS DROPPING BACK BELOW 6 FT. HIGH PRES IS FORECAST TO RIDGE ACROSS THE WATERS ON SATURDAY W/WINDS BECOMING LIGHT AND WAVES DROPPING OFF BELOW 3 FT. CONDITIONS ARE EXPECTED TO STAY BELOW SMALL CRAFT ADVISORY LEVELS INTO MONDAY. && .TIDES/COASTAL FLOODING... 935 AM UPDATE...THE COASTAL FLOOD ADVISORY REMAINS IN PLACE THIS MORNING. WE ARE CLOSELY MONITORING THE CUTLER TIDAL GAGE TO WATCH FOR CHANGES IN EXPECTED STORM SURGE. CURRENT THINKING IS FOR A ONE-FOOT SURGE, WHICH WOULD ALLOW SOME WATER TO COME INTO THE MACIAS TOWN OFFICE PARKING LOT AND NEARBY AREAS, BUT SHOULD NOT THREATEN BUILDINGS. HOWEVER, IF A STRONGER SURGE STARTS TO APPEAR LIKELY, STRUCTURES COULD BE THREATENED AND WE MAY NEED TO UPGRADE THE ADVISORY. WE WILL ALSO MONITOR THE BANGOR RIVER GAGE CLOSELY AS HIGH TIDE APPROACHES. THE HEAVIEST RAIN WILL BE OVER BY THEN, BUT STILL WOULDN`T BE SURPRISED TO SEE SOME MINOR FLOODING IN THE USUAL LOW-LYING SPOTS DOWNTOWN. THE RIVER GAGE MAY OR MAY NOT GO ABOVE FLOOD...IT DID NOT LAST TIME...SO THIS WILL DICTATE WHAT SORT OF FLOOD PRODUCT WE WILL ISSUE, SHOULD ONE BE NECESSARY. PREVIOUS DISCUSSION...PRIMARY CONCERN CONTINUES TO BE COINCIDENCE OF SPRING TIDE WITH STORM SURGE AND LARGE/LONG PERIOD WAVES RESULTING FROM ONGOING STORM SYSTEM. NEXT HIGH TIDE AT 12:33 PM TODAY STILL APPEARS TO COINCIDE WITH LARGEST AND LONGEST PERIOD WAVES WITH OFF-SHORE WAVE HEIGHTS BETWEEN 16 AND 20 FEET AND PERIODS OF 10 TO 12 SECONDS. WAVES APPROACHING COAST NOW EXPECTED TO TO TOP OFF AT AROUND 15 FEET. EXPECT OVERTOPPING AT DEER ISLE CAUSEWAY... SEAWALL ROAD... SCHOODIC POINT... WINTER HARBOR NEAR THE TIME OF HIGH TIDE TODAY. ALSO STRONG WIND FORCING ACROSS PENOBSCOT AND MACHIAS BAYS COMBINED WITH SPRING TIDE COULD RESULT IN TIDAL FLOODING IN MACHIAS AND BANGOR. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...HIGH WIND WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR MEZ015>017- 029-030. COASTAL FLOOD ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR MEZ029-030. MARINE...GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR ANZ050>052. && $$ NEAR TERM...HASTINGS/MIGNONE SHORT TERM...HEWITT LONG TERM...HEWITT AVIATION...HASTINGS/MIGNONE/HEWITT MARINE...HASTINGS/MIGNONE/HEWITT TIDES/COASTAL FLOODING...HASTINGS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1002 AM EDT THU OCT 29 2015 .SYNOPSIS... MORE SHOWERS AND GUSTY WINDS ARE EXPECTED TODAY ACROSS THE NORTH COUNTRY...ALTHOUGH NOT AS MUCH RAIN AND WIND AS YESTERDAY. THE SHOWERS AND GUSTY WINDS WILL BE MOST CONCENTRATED THIS AFTERNOON AS AN UPPER LEVEL TROUGH OF LOW PRESSURE MOVES INTO THE REGION. PRIOR TO THAT...SOME SUNSHINE SHOULD DEVELOP AND MANY AREAS WILL SEE HIGH TEMPERATURES CLIMB INTO THE 60S. THE UPPER LEVEL TROUGH OF LOW PRESSURE WILL EXIST THE REGION LATE THURSDAY NIGHT AND COOLER WEATHER IS EXPECTED FOR FRIDAY. && .NEAR TERM /UNTIL 11 PM THIS EVENING/... AS OF 958 AM EDT THURSDAY...MINOR CHANGES TO FORECAST TO MATCH TEMPERATURE TRENDS AND POPS. BLENDED IN MODEL REFLECTIVITY INTO POP FORECAST TO DOWNPLAY SHOWERS IN VERMONT THROUGH THIS MORNING AND TIME NEXT BATCH OF SHOWERS MOVING ACROSS CENTRAL NY AND EASTERN LAKE ONTARIO. BTV4 LOCAL MODEL AND HRRR HAD GOOD CONSENSUS AND REASONABLE TIMING SO USED THEM. OTHERWISE PARTIAL CLEARING IN PART OF FORECAST AREA IN ADVANCE OF SURFACE FRONT ASSOCIATED WITH THE NEXT BATCH OF RAIN. FORECAST STILL ON TRACK FOR STRONGER WINDS...BUT BELOW ADVISORY LEVEL...IN ST LAWRENCE VALLEY AND FAR NORTHWEST NY. FAVORABLE SOUTHWEST LOW LEVEL FLOW BEHIND THIS FRONT SHOULD DEVELOP OVER NORTHERN NEW YORK IN THE AFTERNOON AND SUFFICIENT MIXING WILL ALLOW FOR GUSTY WINDS TO DEVELOP. 850 MILLIBAR JET MOVING IN AHEAD OF THE UPPER TROUGH IS 2-3 STANDARD DEVIATIONS ABOVE NORMAL...SO WIND GUSTS IN THE 40 TO 45 MILE PER HOUR RANGE WILL BE COMMON WITH A FEW GUSTS TO 50 MPH. SCATTERED SHOWER TO LINGER THROUGH EVENING HOURS. && .SHORT TERM /11 PM THIS EVENING THROUGH SATURDAY/... AS OF 429 AM EDT THURSDAY...UPPER LEVEL AND SURFACE RIDGE WILL BUILD OVER THE REGION FROM FRIDAY THROUGH SATURDAY. TEMPERATURES WILL BE COOL DURING THIS PERIOD WITH MAX TEMPS ONLY IN THE 40S AND MIN TEMPS IN THE 20S. FRIDAY WILL FEATURE SOME SUNSHINE DURING THE AFTERNOON HOURS...BUT BY SATURDAY CLOUDS WILL BE MOVING BACK INTO THE REGION AHEAD OF NEXT APPROACHING SYSTEM. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 429 AM EDT THURSDAY...A SURFACE WARM AND COLD FRONT WILL CROSS OUR FORECAST AREA SUNDAY BRINGING SHOWERS TO THE REGION FOR SATURDAY NIGHT AND SUNDAY...HAVE CONTINUED WITH LIKELY POPS FOR NOW. THIS SYSTEM WILL NOT BE AS WET AS THE PREVIOUS ONE...LACKING THE MOISTURE SOURCE. SHOWERS WILL BE ENDING DURING THE FIRST PART OF SUNDAY NIGHT AND THEN DRIER WEATHER RETURNS FOR THE REST OF THE EXTENDED FORECAST. TEMPERATURES WILL TREND ABOVE SEASONAL NORMALS AS A SURFACE RIDGE BUILDS INTO THE AREA FROM THE SOUTH. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... THROUGH 12Z FRIDAY...EARLY MORNING TREND HAS BEEN FOR IMPROVING CONDITIONS WITH RESPECT TO CEILINGS AND VISIBILITIES AS MAIN AREA OF RAIN MOVES OUT OF THE AREA. THERE MAY BE SOME BRIEF PERIODS OF MVFR/IFR CEILINGS AND VISIBILITIES THROUGH 14Z...THEN VFR AND MVFR CONDITIONS FOR THE REMAINDER OF THE PERIOD. WINDS WILL ONCE AGAIN BE THE MAIN ISSUE TODAY WITH STRONG SOUTHWEST WINDS DEVELOPING BEHIND A COLD FRONT WHICH MOVES ACROSS THE AREA BETWEEN 16Z AND 19Z. EXPECT WIND GUSTS IN THE 30 TO 40 KNOT RANGE OVER NORTHERN NEW YORK AND 25 TO 35 KNOTS FROM THE CHAMPLAIN VALLEY EAST TO THE NEW HAMPSHIRE BORDER. WINDS WILL GRADUALLY TAPER OFF AFTER 03Z. OUTLOOK 12Z FRIDAY THROUGH MONDAY... 12Z FRIDAY THROUGH 18Z FRIDAY...IMPROVING CONDITIONS TO VFR AND DIMINISHING WINDS. 18Z FRIDAY THROUGH 06Z SUNDAY...VFR WITH HIGH PRESSURE BUILDING INTO THE REGION BRINGING DRIER AIR WITH IT. THIS WILL TREND CONDITIONS BACK INTO THE VFR CATEGORY FRIDAY AND INTO THE WEEKEND. 06Z SUNDAY ONWARD...ANOTHER LOW PRESSURE SYSTEM BRING INCREASING CHANCE OF SHOWERS AND MVFR/IFR CONDITIONS POSSIBLE WITH THOSE SHOWERS. && .MARINE... AS OF 434 AM EDT THURSDAY...WINDS HAVE TAPERED OFF INTO THE 10 TO 20 KNOT RANGE EARLY THIS MORNING...BUT A COLD FRONT MOVING INTO THE REGION AROUND MIDDAY WILL ALL FOR STRONGER WEST WINDS TO DEVELOP OVER THE LAKE WITH SPEEDS INCREASING INTO THE 15 TO 25 KNOT RANGE AND WAVES BUILDING TO 3 FEET. THUS A LAKE WIND ADVISORY REMAINS IN EFFECT. WINDS AND WAVES OF THIS MAGNITUDE WILL MAKE FOR DIFFICULT BOATING CONDITIONS...ESPECIALLY FOR SMALL CRAFTS. && .CLIMATE... HIGH TEMPERATURE RECORDS FOR SELECTED SITES ON THURSDAY (10/29) KBTV 71/1946 KMPV 70/1989 K1V4 74/1971 && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...EVENSON NEAR TERM...HANSON SHORT TERM...NEILES LONG TERM...NEILES AVIATION...EVENSON MARINE...EVENSON CLIMATE...JMG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
942 AM CDT THU OCT 29 2015 .UPDATE... ISSUED AT 937 AM CDT THU OCT 29 2015 CLOUDS APPEAR TO BE SLOW TO CLEAR AGAIN TODAY AS THE STRATUS EXTENDS WEST INTO EASTERN MONTANA THIS MORNING. HRRR MODEL KEEPS CLOUDS WEST OF THE MISSOURI THROUGH 21Z. WILL ADJUST TO MAINTAIN CLOUDS THROUGH THAT TIME. WILL PROBABLY SEE ONLY A 5 TO 10 DEGREE DIURNAL TEMPERATURE CHANGE FROM THIS MORNINGS LOW TO THIS AFTERNOONS HIGH MOST AREAS. BISMARCK RADAR SHOWING LAKE EFFECT SNOW SHOWERS DIMINISHING WITH THE WINDS AND SHOULD COMPLETEY END BY LATE MORNING. UPDATE ISSUED AT 636 AM CDT THU OCT 29 2015 GIVEN TRENDS IN THE 08-10 UTC RAP AND HRRR TIME LAGGED ENSEMBLES WHICH DEPICT A SLOWING CLEARING TREND FROM WEST TO EAST THROUGH THE DAY...INCREASED CLOUD COVER THROUGH THE AFTERNOON AND INTO THE EARLY EVENING CENTRAL. ALSO...ADDED POPS FOR LAKE SAKAKAWEA EFFECT SNOW SHOWERS SOUTH CENTRAL THIS MORNING. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 321 AM CDT THU OCT 29 2015 MAINLY QUIET WEATHER TODAY. MAIN CONCERN IS TIMING OF EROSION OF CLOUDS FROM WEST TO EAST AFFECTING THE TEMPERATURE FORECAST. THE STRONG LOW PRESSURE SYSTEM ASSOCIATED WITH THE GUSTY NORTHWEST WINDS AND SNOW SHOWERS ON WEDNESDAY WAS OVER THE GREAT LAKES AREA THIS MORNING...WITH THE ASSOCIATED CLOUD SHIELD SURROUNDING THE LOW EXTENDING WESTWARD ACROSS MANITOBA AND SASKATCHEWAN AND THE DAKOTAS. A WEAK UPPER LEVEL RIDGE WAS OVER THE FRONT RANGE...UPSTREAM FROM THE NEXT UPPER LEVEL LONGWAVE TROUGH DEVELOPING OVER THE WEST COAST. A WEAK SURFACE RIDGE AXIS EXTENDED FROM SASKATCHEWAN SOUTHWARD TO THE ND/MT AND WY/SD BORDERS. THE NORTHWEST WINDS HAD DECREASED GREATLY OVER WESTERN NORTH DAKOTA...WITH WINDS OF 5 TO 10 MPH REPORTED IN THE FAR WEST. THE NORTHWEST WINDS IN THE TURTLE MOUNTAINS THROUGH THE JAMES RIVER VALLEY WERE STILL BRISK AT AROUND 20 MPH AND GUSTING TO AROUND 30 MPH. THE GREAT LAKES LOW PRESSURE SYSTEM IS FORECAST TO CONTINUE MOVING EAST...AND THE UPPER LEVEL SHORTWAVE RIDGE AXIS OVER THE FRONT RANGE AND ITS ASSOCIATED SURFACE RIDGE AXIS IS PROGGED TO MOVE INTO THE DAKOTAS THIS AFTERNOON. EXPECT THE NORTHWEST WINDS OVER CENTRAL NORTH DAKOTA TO BECOME LIGHT THIS AFTERNOON...WITH WINDS IN THE WEST BECOMING SOUTHERLY. THE LOW CLOUDS SHOULD DISSIPATE FROM WEST TO EAST TODAY...WITH SOME LINGERING FLURRIES IN CENTRAL NORTH DAKOTA EARLY THIS MORNING. LOOK FOR HIGHS FROM THE MID 40S IN THE SOUTHWEST...WITH TEMPERATURES REMAINING IN THE MID 30S IN THE TURTLE MOUNTAINS WHERE CLOUDS WILL LIKELY NOT DISSIPATE UNTIL LATER THIS AFTERNOON. TONIGHT THE NEXT UPPER LEVEL LONGWAVE TROUGH MOVES EAST ACROSS THE ROCKIES...WITH SURFACE LOW PRESSURE DEVELOPING OVER THE FRONT RANGE. MAINLY CLEAR SKIES TONIGHT ACROSS THE FORECAST AREA...BUT MID CLOUDS MOVING INTO THE WEST LATE. LOWS TONIGHT SHOULD BE IN THE UPPER 20S IN THE CENTRAL...TO THE LOWER 30S WEST. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 321 AM CDT THU OCT 29 2015 A CLIPPER SYSTEM ON SATURDAY AND POTENTIALLY UNSETTLED WEATHER MID NEXT WEEK HIGHLIGHTS THE EXTENDED FORECAST. THE 00 UTC DETERMINISTIC SUITE IS IN AGREEMENT ON A CLIPPER SYSTEM TO IMPACT WESTERN AND CENTRAL NORTH DAKOTA SATURDAY MORNING AND INTO THE AFTERNOON. A CHANCE OF RAIN...POSSIBLY MIXED WITH SNOW IN THE MORNING...IS EXPECTED FOR MUCH OF THE AREA...WITH DRY CONDITIONS FORECAST BY EVENING. THERE IS SOME DISAGREEMENT REGARDING THE POTENTIAL STRENGTH OF THE WINDFIELD IN THE WAKE OF THE CLIPPER THROUGH THE AFTERNOON WITH THE 00 UTC GFS THE STRONGEST RESULTING FROM THE DEEPEST SURFACE LOW. THEREAFTER...THE 00 UTC SUITE IS IN AGREEMENT ON A LONGWAVE UPPER LEVEL TROUGH POTENTIALLY DEVELOPING ACROSS THE WESTERN CONUS BY EARLY TO MID NEXT WEEK. THIS IS A FAVORABLE PATTERN FOR POSSIBLY WET AND UNSETTLED WEATHER FOR THE NORTHERN PLAINS. WHILE MUCH UNCERTAINTY REMAINS...TRENDS OVER THE COMING DAYS FOR THIS PERIOD WILL HAVE TO BE MONITORED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 636 AM CDT THU OCT 29 2015 WIDESPREAD MVFR STRATUS THIS MORNING WILL SLOWLY DECREASE FROM WEST TO EAST LATE THIS MORNING THROUGH THE EARLY EVENING. A BRIEF PERIOD OF LIGHT SNOW FROM LAKE SAKAKAWEA EFFECT SHOWERS ARE POSSIBLE AT KBIS THIS MORNING. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...JV LONG TERM...AYD AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
644 AM CDT THU OCT 29 2015 .UPDATE... ISSUED AT 636 AM CDT THU OCT 29 2015 GIVEN TRENDS IN THE 08-10 UTC RAP AND HRRR TIME LAGGED ENSEMBLES WHICH DEPICT A SLOWING CLEARING TREND FROM WEST TO EAST THROUGH THE DAY...INCREASED CLOUD COVER THROUGH THE AFTERNOON AND INTO THE EARLY EVENING CENTRAL. ALSO...ADDED POPS FOR LAKE SAKAKAWEA EFFECT SNOW SHOWERS SOUTH CENTRAL THIS MORNING. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 321 AM CDT THU OCT 29 2015 MAINLY QUIET WEATHER TODAY. MAIN CONCERN IS TIMING OF EROSION OF CLOUDS FROM WEST TO EAST AFFECTING THE TEMPERATURE FORECAST. THE STRONG LOW PRESSURE SYSTEM ASSOCIATED WITH THE GUSTY NORTHWEST WINDS AND SNOW SHOWERS ON WEDNESDAY WAS OVER THE GREAT LAKES AREA THIS MORNING...WITH THE ASSOCIATED CLOUD SHIELD SURROUNDING THE LOW EXTENDING WESTWARD ACROSS MANITOBA AND SASKATCHEWAN AND THE DAKOTAS. A WEAK UPPER LEVEL RIDGE WAS OVER THE FRONT RANGE...UPSTREAM FROM THE NEXT UPPER LEVEL LONGWAVE TROUGH DEVELOPING OVER THE WEST COAST. A WEAK SURFACE RIDGE AXIS EXTENDED FROM SASKATCHEWAN SOUTHWARD TO THE ND/MT AND WY/SD BORDERS. THE NORTHWEST WINDS HAD DECREASED GREATLY OVER WESTERN NORTH DAKOTA...WITH WINDS OF 5 TO 10 MPH REPORTED IN THE FAR WEST. THE NORTHWEST WINDS IN THE TURTLE MOUNTAINS THROUGH THE JAMES RIVER VALLEY WERE STILL BRISK AT AROUND 20 MPH AND GUSTING TO AROUND 30 MPH. THE GREAT LAKES LOW PRESSURE SYSTEM IS FORECAST TO CONTINUE MOVING EAST...AND THE UPPER LEVEL SHORTWAVE RIDGE AXIS OVER THE FRONT RANGE AND ITS ASSOCIATED SURFACE RIDGE AXIS IS PROGGED TO MOVE INTO THE DAKOTAS THIS AFTERNOON. EXPECT THE NORTHWEST WINDS OVER CENTRAL NORTH DAKOTA TO BECOME LIGHT THIS AFTERNOON...WITH WINDS IN THE WEST BECOMING SOUTHERLY. THE LOW CLOUDS SHOULD DISSIPATE FROM WEST TO EAST TODAY...WITH SOME LINGERING FLURRIES IN CENTRAL NORTH DAKOTA EARLY THIS MORNING. LOOK FOR HIGHS FROM THE MID 40S IN THE SOUTHWEST...WITH TEMPERATURES REMAINING IN THE MID 30S IN THE TURTLE MOUNTAINS WHERE CLOUDS WILL LIKELY NOT DISSIPATE UNTIL LATER THIS AFTERNOON. TONIGHT THE NEXT UPPER LEVEL LONGWAVE TROUGH MOVES EAST ACROSS THE ROCKIES...WITH SURFACE LOW PRESSURE DEVELOPING OVER THE FRONT RANGE. MAINLY CLEAR SKIES TONIGHT ACROSS THE FORECAST AREA...BUT MID CLOUDS MOVING INTO THE WEST LATE. LOWS TONIGHT SHOULD BE IN THE UPPER 20S IN THE CENTRAL...TO THE LOWER 30S WEST. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 321 AM CDT THU OCT 29 2015 A CLIPPER SYSTEM ON SATURDAY AND POTENTIALLY UNSETTLED WEATHER MID NEXT WEEK HIGHLIGHTS THE EXTENDED FORECAST. THE 00 UTC DETERMINISTIC SUITE IS IN AGREEMENT ON A CLIPPER SYSTEM TO IMPACT WESTERN AND CENTRAL NORTH DAKOTA SATURDAY MORNING AND INTO THE AFTERNOON. A CHANCE OF RAIN...POSSIBLY MIXED WITH SNOW IN THE MORNING...IS EXPECTED FOR MUCH OF THE AREA...WITH DRY CONDITIONS FORECAST BY EVENING. THERE IS SOME DISAGREEMENT REGARDING THE POTENTIAL STRENGTH OF THE WINDFIELD IN THE WAKE OF THE CLIPPER THROUGH THE AFTERNOON WITH THE 00 UTC GFS THE STRONGEST RESULTING FROM THE DEEPEST SURFACE LOW. THEREAFTER...THE 00 UTC SUITE IS IN AGREEMENT ON A LONGWAVE UPPER LEVEL TROUGH POTENTIALLY DEVELOPING ACROSS THE WESTERN CONUS BY EARLY TO MID NEXT WEEK. THIS IS A FAVORABLE PATTERN FOR POSSIBLY WET AND UNSETTLED WEATHER FOR THE NORTHERN PLAINS. WHILE MUCH UNCERTAINTY REMAINS...TRENDS OVER THE COMING DAYS FOR THIS PERIOD WILL HAVE TO BE MONITORED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 636 AM CDT THU OCT 29 2015 WIDESPREAD MVFR STRATUS THIS MORNING WILL SLOWLY DECREASE FROM WEST TO EAST LATE THIS MORNING THROUGH THE EARLY EVENING. A BRIEF PERIOD OF LIGHT SNOW FROM LAKE SAKAKAWEA EFFECT SHOWERS ARE POSSIBLE AT KBIS THIS MORNING. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...JV LONG TERM...AYD AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
745 AM EDT THU OCT 29 2015 .SYNOPSIS... A COLD FRONT WILL MOVE EAST ACROSS THE REGION TODAY. HIGH PRESSURE ARRIVES TONIGHT INTO FRIDAY FROM THE WEST. THIS HIGH WILL MOVE OFFSHORE THIS WEEKEND...WHILE ANOTHER LOW PRESSURE AREA FORMS OVER THE LOWER MISSISSIPPI VALLEY BRING MORE MOISTURE OUR WAY SUNDAY INTO MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 352 AM EDT THURSDAY... THE COMBINATION OF LIGHT WINDS AND SOME CLEARING BEHIND THE FIRST COLD FRONT RESULTED IN PATCHY LOW CLOUDS AND FOG THIS MORNING. FOG IS QUITE VARIABLE AND GENERALLY IN THE VALLEYS. MORNING FOG WILL MIX OUT QUICKLY AS WIND SPEEDS INCREASE AHEAD OF ANOTHER FRONTAL BOUNDARY. THE SECOND COLD FRONT WILL PUSH EAST ACROSS THE REGION TODAY AND REACH THE ATLANTIC COAST TONIGHT. THE HIGHRESW- ARW-EAST...RNK WRFARW...NAM AND GFS SHOWED SOME SCATTERED MORNING SHOWERS IN THE MOUNTAINS. THE HRRR PLACED SOME ISOLATED SHOWERS IN THE FOOTHILLS THIS AFTERNOON AS A FRONT TRAVELS ACROSS THE AREA. BELIEVE THAT THE SHOWERS ARE OVERDONE WITH THE WEST FLOW. UPSLOPE CLOUDS WILL LINGER IN THE WESTERN MOUNTAINS. WHILE...SUNSHINE WILL RETURN TO THE EAST THIS AFTERNOON. HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE UPPER 50S IN THE NORTHWEST MOUNTAINS TO THE MID 70S IN THE PIEDMONT. DRIER AIR WILL FILTER INTO OUR REGION TONIGHT...WHILE HIGH PRESSURE REMAINS WEST OF THE AREA WITH NORTHWEST FLOW WEAKENING. LOW LEVEL THICKNESSES COOL ENOUGH THAT LOW TEMPERATURES WILL VARY FROM THE MID TO UPPER 30S IN THE MOUNTAINS TO THE LOWER 40S IN THE PIEDMONT. && .SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/... AS OF 445 AM EDT THURSDAY... WHAT STARTS OUT INITIALLY AS A PROGRESSIVE FLOW BECOMES SPLIT AND BLOCKED THROUGH THIS PERIOD AS A DEEP UPPER LOW ATTEMPTS TO SHIFT OUT OF THE SOUTHWEST U.S. AND AN UPPER RIDGE DEVELOPS OFF THE SOUTHEAST U.S. COAST. A LARGE HIGH PRESSURE AREA WILL DRIFT INTO THE REGION FROM THE WEST FRIDAY WITH WEST-NORTHWEST FLOW ALOFT. DECREASING WINDS...SUNNY SKIES...AND SEASONABLE TEMPERATURES ARE EXPECTED. 850MB TEMPS REMAIN ABOVE FREEZING EXCEPT IN THE FAR NORTH...SO OTHER THAN THE HIGHER MOUNTAINS AND A FEW DEEPER VALLEYS WITHIN THE MOUNTAINS...FREEZING TEMPERATURES ARE NOT EXPECTED. DURING THE DAY SATURDAY...THE SURFACE HIGH WILL DRIFT OFF THE MID-ATLANTIC COAST AS A FAST MOVING NORTHERN STREAM SHORT WAVE ATTEMPTS TO PICK UP THE LINGERING UPPER LOW ACROSS TEXAS. MEANWHILE...A BLOCKING 592DM UPPER RIDGE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST. THE NORTHERN STREAM SHORT WAVE WILL SPREAD PRECIPITATION INTO OUR REGION BY SATURDAY EVENING...BUT ESPECIALLY INTO SUNDAY MORNING. BY SUNDAY AFTERNOON...THE NORTHERN STREAM SHORT WAVE HAS MOVED WELL NORTHEAST OF THE REGION...BUT THE SOUTHERN STREAM UPPER SHORT WAVE ACROSS AL/GA WILL BE LEFT BEHIND...ALBEIT SHEARING OUT. A BAROCLINIC ZONE WILL LINGER ACROSS THE SOUTHEAST STATES AND POTENTIALLY NORTHEAST INTO VA. WHILE THE MODELS HANDLE THE TRACK AND TIMING OF THE NORTHERN STREAM SHORT WAVE SAT-SUN WELL...THE SUBSEQUENT HANDLING OF THE UPPER TROUGH ACROSS THE SOUTHEAST STATES IS POORLY HANDLED. THE ECMWF TRACKS MUCH OF THE MOISTURE WELL NORTH INTO THE MID- ATLANTIC...WHILE THE GFS RAPIDLY TAKES IT EAST-SOUTHEAST OFF THE ATLANTIC COAST. THE ECMWF SOLUTION COULD POTENTIALLY LEAD TO HYDRO ISSUES...WHILE THE GFS WOULD NOT. WPC HAS INDICATED THAT A SWATH OF HEAVY RAIN WILL TRACK FROM NEAR BHM-ATL-CAE...REMAINING WELL SOUTH OF OUR REGION WITH GENERAL AMOUNTS OF 1.0 INCH IN OUR SOUTHERN CWA TO 1/2 INCH NORTH. THIS WILL NOT BE A WEDGE EVENT...MORE OF A SOUTHWEST FLOW EVENT...AND THUS THERE SHOULD NOT BE ENHANCEMENT ALONG THE BLUE RIDGE AS WITH SOME OF OUR PREVIOUS EVENTS. NONETHELESS...THE GROUND IS NOW SATURATED FROM GENERAL 1.5 TO 2.5 INCH RAINFALL LAST TWO DAYS. THUS...TO ACCOUNT FOR UNCERTAINTY..WILL WORD EXTENDED PORTION OF HWO AS "PROBABILITY IS LOW" RATHER THAN "NO HAZARDS". ALSO IN THIS REGARD...HAVE CARRIED LOW CHANCE/SLIGHT CHANCE POPS LONGER IN THESE PERIODS THAN I REALLY WANTED TO IN DEFERENCE TO THE ECMWF. TEMPERATURES WILL REMAIN ABOVE SEASONAL NORMALS THROUGH THE PERIOD...ON THE AVERAGE OF 10 DEGREES. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF 415 AM EDT THURSDAY... THE BAROCLINIC ZONE TO OUR SOUTHEAST SHOULD FINALLY BE KICKED OUT TO SEA BY TUE AS ANOTHER DEEP UPPER TROUGH BUILDS INTO THE SOUTHEAST U.S. IN RESPONSE...A HIGH AMPLITUDE 592DM RIDGE WILL BUILD ACROSS THE EASTERN U.S....CENTERED ACROSS FL/GA. MEANWHILE...A NEW BAROCLINIC ZONE WILL DEVELOP ACROSS TEXAS INTO THE WESTERN TN VALLEY. GIVEN THE INCREASING AMPLITUDE OF THE FLOW AND BLOCKING RIDGE ACROSS THE SOUTHEAST...CONFIDENCE IN WHEN THIS AREA OF RAIN WILL REACH OUR AREA IS LOW AT THIS TIME. HAVE LEFT THE LATER PERIODS OF THE EXTENDED PERIOD DRY FOR NOW. TEMPERATURES WILL REMAIN WELL ABOVE NORMAL THROUGH THE PERIOD WITH SEVERAL DAYS IN THE 70S POSSIBLE ACROSS THE PIEDMONT...60S ACROSS THE MOUNTAINS. MIN TEMPS WILL REMAIN WELL ABOVE FREEZING. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... AS OF 740 AM EDT THURSDAY... TRUE COLD FRONT EVIDENT ALONG THE ALLEGHANY FRONT OF WV AT THIS HOUR WITH A NARROW LINE OF RAIN SHOWERS. THESE SHOWERS WILL MOVE TOWARD A LWB-BLF LINE...THEN DISSIPATE WITH INCREASING DOWNSLOPE EFFECT TO THE EAST. BRIEF MVFR VSBYS POSSIBLE BLF-LWB WITH THE -SHRA. OTHERWISE...TENDENCY WILL BE FOR CLEARING TO THE EAST AND VFR CONDITIONS BY MID-MORNING ROA/LYH/DAN...WITH MVFR CIGS HOLDING INTO AT LEAST MID-AFTERNOON BLF/LWB...EARLY AFTERNOON BCB. ANY LOW CLOUDS/FOG EAST OF THE BLUE RIDGE WILL QUICKLY DISSIPATE BY 14Z. BY EVENING...HIGH PRESSURE WILL BEGIN TO BUILD INTO THE REGION FROM THE WEST WITH SKIES CLEARING IN THE WEST. VFR CIGS/VSBYS ARE EXPECTED FOR THE REMAINDER OF THE TAF VALID PERIOD AFT 00Z WEST OF THE BLUE RIDGE. WINDS WILL BECOME W-WNW THROUGH 14Z AND INCREASE IN SPEED TO 10-15KTS WITH GUSTS TO 25KTS WEST OF THE BLUE RIDGE AS A DEEP LOW PRESSURE AREA MOVING THROUGH THE GREAT LAKES REGION. WINDS WILL DIMINISH TO 10KTS OR LESS AFT 00Z FRI. MEDIUM CONFIDENCE IN CIGS THROUGH 00Z...THEN HIGH CONFIDENCE IN VFR CIGS. MEDIUM TO HIGH CONFIDENCE IN VSBYS THROUGH 16Z...THEN HIGH CONFIDENCE IN VFR VSBYS. HIGH CONFIDENCE IN WIND DIRECTION THROUGH THE TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN WIND SPEED THROUGH THE TAF VALID PERIOD. EXTENDED AVIATION DISCUSSION... VFR CONDITIONS ARE EXPECTED FRI-SAT AS A LARGE SURFACE HIGH BUILDS ACROSS THE REGION. WINDS WILL DIMINISH FRIDAY. THE NEXT CHANCE FOR RAIN AND SUB-VFR CIGS WILL COME SUNDAY-MONDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...KK/WP NEAR TERM...KK SHORT TERM...RAB LONG TERM...RAB/WP AVIATION...AMS/KK/RAB Area Forecast Discussion National Weather Service Spokane WA 444 AM PDT THU OCT 29 2015 .SYNOPSIS... Light rain will continue this morning then taper off this afternoon. This break period will end on Friday as a deep fetch of Pacific moisture feeds into the region promoting widespread rain on Friday and into Saturday. Windy and gusty conditions will also develop for a damp and blustery Halloween. Unsettled conditions with occasional wet periods will continue into next week. && .DISCUSSION... Today and tonight...A shortwave trough will bring some light precipitation to the Inland Northwest today. One area of light precipitation is moving across extreme eastern WA and north ID as of 2 am. A second band is just barely holding together as it crosses the deep basin but should regain some organization as it encounters the rising terrain east of the basin. This feature will bring another round of light precipitation to the eastern half of the forecast area later this morning. The HRRR and NAM have tracked the first band well so the near term forecast is leaning heavily toward this guidance. Once the trough axis moves off to the east, scattered rain showers will continue in moist upslope flow into the Idaho Panhandle tonight while the remainder of the forecast area has a brief respite from the wet weather. Friday through Sunday...Wetter and windier conditions will begin on Friday as fire hose of an atmospheric river is aimed at the Pacific Northwest. Snow levels will remain high for Friday and Saturday as the subtropical moisture tap pushes into the forecast area. Persistent warm frontal precipitation will begin on Friday and continue into Saturday. A cold front will bring an end to the steady precip and usher in more scattered showers late Saturday. The timing of this break in the wet weather will be critical to trick-or-treaters who wish to remain dry...or at least not drenched. for Sunday, the upper trough will slide over the region with more scattered valley rain and mountain snow showers. Snow levels could fall as low as 3000 ft with mountain passes collecting some snowfall. More details on this to come in the next day or two. Storm total rainfall from Friday through Sunday will be in the one to two and a half inch range in the Idaho Panhandle and Cascades with a general one third to one half inch in the basin...except a tenth or two in the downslope deep basin area. The rising terrain east of the basin will see a half inch to and inch of rainfall. Winds will be a significant issue starting Friday and lasting through Saturday with gust potential in the well mixed warm sector potentially approaching 40 mph over exposed terrain. Winds will remain blustery through Sunday night. Monday through Thursday...The region will be under cool and unstable northerly flow as the work week begins. This will keep a chance of showers in the forecast but as the base of the trough digs south, the tap into deep Pacific moisture will be lost. Valley rain and mountain snow will be showery in nature with light amounts of precipitation compared to the weekend system. Temperatures will be near seasonal normals. /Kelch && .AVIATION... 12Z TAFS:One band of rain showers is moving into the Idaho panhandle and a second band is moving across the basin as of 11Z. These two features will continue to bring IFR/LIFR conditions to TAF sites other than KEAT and KLWS. Once the second band reaches the ID border around 15Z...conditions will begin to improve with MVFR conditions expected by 18Z. Gusty SW winds will develop this afternoon, mixing out the low ceilings. Winds will subside after 03Z and MVFR ceilings may return. /EK && .PRELIMINARY POINT TEMPS/POPS... Spokane 53 43 55 48 58 46 / 20 10 80 80 80 20 Coeur d`Alene 52 41 52 47 56 46 / 40 20 90 90 90 40 Pullman 56 43 55 47 57 46 / 20 20 80 80 80 50 Lewiston 60 46 61 52 62 50 / 20 20 80 70 70 50 Colville 52 39 52 42 54 42 / 80 10 80 80 80 20 Sandpoint 51 39 51 42 54 43 / 60 30 90 100 100 40 Kellogg 48 39 48 44 51 45 / 70 40 100 100 100 70 Moses Lake 61 44 65 48 62 47 / 40 10 50 40 50 10 Wenatchee 60 46 63 51 60 47 / 0 10 40 30 50 0 Omak 56 41 58 44 58 43 / 50 10 70 50 70 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS MIAMI FL
327 PM EDT THU OCT 29 2015 .SYNOPSIS... A NEAR PERFECT ZONAL MID FLOW PATTERN CURRENTY EXISTS ACROSS THE FLORIDA PENINSULA WITH A WEAKENING OLD SURFACE FRONTAL BOUNDARY DRAPED ACROSS SOUTH FLORIDA THIS AFTERNOON ALTHOUGH IT APPEARS ON VISIBLE SATELLITE TO HAVE SAGGED TO THE EXTREME SOUTHERN TIP OF THE PENINSULA OR EVEN THE FAR NORTHERN KEYS. THIS SHOULD BE THE FOCUS OF ANY SHOWER OR THUNDERSTORM DEVELOPMENT SO IT WOULD SEEM TO BE FOCUSED OVER THE FAR SOUTHERN ZONES AND HAVE THUS LOWERED THE POPS FARTHER TO THE NORTH. THE HRRR ALSO DOES NOT GET VERY EXCITED OTHER THAN MOSTLY THE SOUTHEAST ZONES. && .SHORT TERM (TONIGHT-SATURDAY NIGHT)... THE ZONAL FLOW WILL CONTINUE ACROSS THE REGION THROUGH FRIDAY WITH FRONTAL BOUNDARY CONTINUING TO WEAKEN. MODEL GUIDANCE EVEN SHOWS THE LOW LEVEL BOUNDARY LAYER TO DRY EVEN FURTHER SO SHOWER ACTIVITY SHOULD BE AT A MINIMUM ON FRIDAY. A MID TO UPPER LEVEL RIDGE WILL BEGIN TO AMPLIFY ACROSS THE REGION ON SATURDAY AND SATURDAY NIGHT AS A STRONG TROUGH DEEPENS INTO THE SOUTHERN PLAINS. A SURFACE RIDGE OF HIGH PRESSURE CURRENTLY CENTERED OVER THE CENTRAL PLAINS WILL SHIFT EAST THROUGH THIS PERIOD KEEPING A LOW LEVEL EAST TO SOUTHEAST WIND ACROSS SOUTH FLORIDA. LITTLE IN THE WAY OF SHOWER ACTIVITY IS EXPECTED WITH THE STRENGTHENING UPPER RIDGE BUILDING INTO THE AREA. IN ADDITION, THE MINOR COASTAL FLOODING WITH THE ASTRONOMICAL HIGH TIDES WILL BE LESSENING AS THE WEEK PROGRESSES DUE TO THE WANING MOON. THE COASTAL FLOOD STATEMENT WILL CONTINUE THROUGH THIS EVENING AND MAY NEED TO BE EXTENDED INTO FRIDAY IF REPORTS AT HIGH TIDE THIS EVENING DICTATE. .LONG TERM (SUNDAY-THURSDAY)... IN THE EXTENDED PERIOD, THE UPPER RIDGE WILL ONLY WEAKEN SLIGHTLY BUT REMAIN OVER THE REGION WHILE THE TROUGH IN THE SOUTHERN PLAINS WEAKENS SIGNIFICANTLY THROUGH EARLY NEXT WEEK AS IT PIVOTS ACROSS THE NORTHERN PERIPHERY OF THE RIDGE AXIS. THE COLD FRONT ASSOCIATED WITH THE TROUGH WILL MOVE INTO NORTH FLORIDA ON MONDAY WITH THE GFS SHOWING IT MOVING INTO CENTRAL FLORIDA ON TUESDAY WHERE IT WILL STALL IN A WEAKENING STATE. HOWEVER, THE ECMWF SHOWS IT STALLING ACROSS NORTH FLORIDA. DEPENDING ON HOW FAR SOUTH IT GETS NEXT WEEK, THERE COULD BE AN INCREASE IN SHOWER ACTIVITY TOWARDS THE END OF THE FORECAST. TYPICALLY, THE FIRST SIGNIFICANT COLD FRONT OF THE SEASON ARRIVES BETWEEN MID AND LATE NOVEMBER AND THERE IS CURRENTLY NO SIGN OF THAT HAPPENING JUST YET. BUT, GOOD THINGS COME TO THOSE WHO WAIT AND AFTER ALL IT IS STILL A LITTLE EARLY. && .MARINE... AS THE FRONTAL BOUNDARY CONTINUES TO WEAKEN THIS EVENING AND HIGH PRESSURE BUILDS OVER THE SOUTHEAST STATES, THE WIND WILL BECOME LIGHT EASTERLY OVERNIGHT AND REMAIN EASTERLY THROUGH THE PERIOD WITH SEAS OF GENERALLY 4 FEET OR LESS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 71 86 76 87 / 30 30 20 30 FORT LAUDERDALE 73 85 75 86 / 20 30 40 30 MIAMI 74 87 75 87 / 20 30 30 30 NAPLES 71 86 73 88 / 10 10 0 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...30/KOB LONG TERM....30/KOB AVIATION.....60/BD/AA
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
302 PM CDT THU OCT 29 2015 .SHORT TERM...(Tonight) ISSUED AT 302 PM CDT THU OCT 29 2015 Broad cyclonic flow continuing this afternoon around the low departing eastern Ontario, as a surface trough rotates southeast through the Great Lakes. Cloud shield has covered most of the forecast area north of I-70, but last few frames of the visible satellite loop suggest it may not reach much further. RAP humidity plots do show a bit more progress though, and will keep skies partly cloudy across the southeast CWA this evening. Over the remainder of the forecast area, a clearing trend should start from the southwest this evening, but have lingered the cloud cover over the northeast CWA much of the night. Little change needed in low temperatures, which should bottom out a couple degrees either side of 35. && .LONG TERM...(Friday through Thursday) ISSUED AT 302 PM CDT THU OCT 29 2015 High pressure expected to build back into the Midwest tonight, eventually eroding the clouds towards morning with lighter winds. Ridge axis moves over the region tomorrow, with some variability to the lighter winds and sunny, highs warmer than today into the upper 50s. Deep upper low over the southern states moving out across the country as another upper low and developing low pressure system moves across the southern border of Canada...bringing rain for the end of the week. Starting in the west Friday evening and spreading across the region for all day Saturday. Halloween day expected to be rather wet and gray...but should be coming to an end from west to east later in the night. At this point, the timing looks to show some clearing nw of the Illinois River Valley around 6-7pm. Expect timing to become more finely tuned in the next few forecasts. Beyond the weekend and into next week, the Midwest becomes largely dominated by a high pressure ridge just to the east, keeping the area dry for the most part, with a warming trend. Southwesterly flow aloft and 850 mb temps climbing to 15-16C by Tuesday, and highs once again well above seasonal norms, in the upper 60s/lower 70s through Wed/Thu. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) ISSUED AT 1226 PM CDT THU OCT 29 2015 MVFR cloud deck has reached the KSPI-KCMI corridor at midday. Some modest rise in ceiling heights is expected with time, but widespread MVFR ceilings will remain in place into the evening. Have kept the cloud heights down at KBMI/KCMI much of the night, but areas further west should see improving conditions by 06Z. Gusty west winds to around 25 knots will quickly decrease around 23Z. Winds will become light and variable overnight as high pressure drifts overhead, then become more southerly Friday morning on the back side of the high. && .ILX Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Geelhart LONG TERM...HJS AVIATION...Geelhart
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1226 PM CDT THU OCT 29 2015 .UPDATE... ISSUED AT 951 AM CDT THU OCT 29 2015 Stratocumulus deck continues to sink southward this morning, with the leading edge roughly from Quincy to Lincoln to Watseka. RAP model humidity guidance suggesting this could make it as far south as about I-70, before a clearing push begins from the southwest late this afternoon. Winds already gusting up to near 30 mph in much of the CWA, with the HRRR showing the gustiness lasting through mid afternoon before some tapering begins. Existing forecast was largely on track and only required some minor tweaks. The worded forecasts were updated to reflect the latest sky trends. && .SHORT TERM...(Today) ISSUED AT 326 AM CDT THU OCT 29 2015 Unseasonably deep 521dm 500mb low continues to spin over Lake Michigan this morning, while a significant vorticity max rotates southward around the parent low across Minnesota. Low cloudiness associated with the vort lobe will gradually spill southward today, impacting the northern half of the KILX CWA. NAM 1000-850mb RH field is handling the current cloud cover quite well, so will follow this parameter closely for the sky cover forecast today. As a result, am expecting mostly clear skies across the board at dawn with overcast conditions developing along/north of the I-74 corridor toward midday into the afternoon hours. Will also be a windy day as pressure gradient between low over the Great Lakes and high building into the Plains remains tight. Forecast soundings and numeric guidance both suggest sustained winds of 15-20mph with gusts to between 25 and 30mph at times. Due to continued CAA, high temperatures will remain well below normal...with readings ranging from the upper 40s far north where cloud cover will be prevalent to the middle 50s along/south of I-70 where skies will remain sunny. .LONG TERM...(Tonight through Wednesday) ISSUED AT 326 AM CDT THU OCT 29 2015 High pressure will build into the Midwest tonight, providing clearing skies and diminishing winds. Overnight lows will dip into the lower to middle 30s. After a sunny/cool day on Friday with highs mainly in the 50s, an approaching northern stream short-wave will spread clouds and showers back into the area Friday night into Saturday. Models are in good agreement with the timing of this feature and the overall QPF...with rainfall totals generally around half an inch. Given presence of an initially dry airmass associated with the departing high, will continue to keep Friday evening dry. However, as stronger upper dynamics approach from the west and mid/low-level airmass moistens, will introduce likely PoPs along/west of I-55 and chance PoPs further east across the remainder of the CWA after midnight. Best rain chances are still on target for Saturday, when widespread showers are expected. Upper wave is progressive and will quickly push off to the east Saturday night. Will linger showers into Saturday evening, but will dry things out from west to east overnight. Models have come into better agreement concerning evolution and track of upper low initially in place over the Desert Southwest this weekend. Previous runs had shown a highly amplified closed low, but the 00z Oct 29 model suite now indicates a much weaker open feature that ejects eastward more quickly. Both the GFS and ECMWF take this wave into the Tennessee River Valley Sunday night into Monday, keeping any precip well S/SE of Illinois. Meanwhile, the GEM continues to be the odd model out by bringing the wave much further north and spreading rain into the CWA on Monday. Given clear trend toward a weaker/faster/more southern solution, have rejected the GEM in favor of the GFS/ECMWF consensus. As such, have gone with a dry forecast Sunday through Tuesday with a steady warming trend. As has been the case for the past several days, models continue to show rising upper heights across the region early next week. 850mb temps on both the GFS and ECMWF are progged to reach the 14-16C range by Tuesday and Wednesday, supporting highs into the 70s. GFS tries to bring moisture northward in the WAA regime as early as Wednesday, but think this is too aggressive, especially given the fact that the ECMWF holds any precip off until Friday at the earliest. As a result, will continue the dry forecast through Wednesday. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) ISSUED AT 1226 PM CDT THU OCT 29 2015 MVFR cloud deck has reached the KSPI-KCMI corridor at midday. Some modest rise in ceiling heights is expected with time, but widespread MVFR ceilings will remain in place into the evening. Have kept the cloud heights down at KBMI/KCMI much of the night, but areas further west should see improving conditions by 06Z. Gusty west winds to around 25 knots will quickly decrease around 23Z. Winds will become light and variable overnight as high pressure drifts overhead, then become more southerly Friday morning on the back side of the high. && .ILX Watches/Warnings/Advisories... NONE. && $$ UPDATE...Geelhart SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CARIBOU ME
114 PM EDT THU OCT 29 2015 .SYNOPSIS... SOAKING RAIN AND GUSTY WINDS WILL PERSIST TODAY WHILE STRONG LOW PRESSURE TRACKS NORTHWEST OF MAINE. COLDER WEATHER RETURNS FRIDAY WITH GUSTY NORTHWEST WINDS. HIGH PRESSURE WILL MOVE OVER THE REGION ON SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... 105 PM UPDATE...AS EXPECTED, WE`RE SEEING A BRIEF BREAK FROM THE STEADY RAIN AS THE WARM FRONT LIFTS THROUGH THE REGION. WINDS HAVE SUBSIDED AS WELL SINCE THE LOW LEVEL JET HAS EXITED INTO NEW BRUNSWICK. ALTHOUGH GUSTS TO 30 MPH WILL CONTINUE TO BE POSSIBLE, WIDESPREAD DAMAGING WINDS ARE NOT ANTICIPATED THIS AFTERNOON. HAVE HAVE THEREFORE CANCELLED THE HIGH WIND WARNING. SEE THE TIDE/COASTAL SECTION FOR AN UPDATE ON THE CURRENT THOUGHT OUR FOCUS NOW TURNS TO A POTENTIAL SQUALL LINE FOR LATE THIS AFTERNOON INTO THE EVENING. TEMPERATURES HAVE RISEN INTO THE 60S IN MOST LOCATIONS, AND EXPECT THIS TREND TO CONTINUE AS WE`RE SEEING SOME BREAKS ON SATELLITE IMAGERY. DEWPOINTS ARE ALSO IN THE 60S. AS SUCH, THERE WILL BE INSTABILITY AVAILABLE FOR CONVECTION DEVELOPMENT ALONG THE COLD FRONT THAT WILL CROSS FROM WEST TO EAST LATER TODAY. THERE`S STILL PLENTY OF WIND AVAILABLE OFF THE SURFACE FOR MIXING...WITH THE HRRR AND NAM INDICATING THE POTENTIAL FOR GUSTS TO 50 MPH. THIS WILL BEAR WATCHING CLOSELY AS THE FRONT DRAWS NEAR. PREVIOUS DISCUSSION...INTENSE LOW PRESSURE OVER THE WESTERN GREAT LAKES WILL MOVE NORTHEAST INTO CANADA TODAY. THIS SYSTEM IS EXPECTED TO PRODUCE STRONG SOUTHERLY WINDS...HEAVY RAIN ALONG WITH SOME ISOLATED THUNDERSTORMS. A COLD FRONT WILL MOVE THROUGH LATER TODAY WITH A MUCH COLDER AIR MASS MOVING IN BEHIND THE FRONT THIS TONIGHT. COLD ADVECTION WILL CONTINUE TONIGHT ALONG WITH AN UPPER LEVEL LOW PRESSURE SYSTEM. THE UPPER LOW WILL PRODUCE SOME SHOWERS EARLY TONIGHT WITH SNOW SHOWERS LATER TONIGHT AS COLDER AIR MOVES IN. FOR MAXIMUM TEMPERATURE WILL USE THE CONSENSUS BLEND AND FOR MINIMUM TEMPERATURE WILL USE THE BIAS CONSENSUS MOS BASED ON VERIFICATION LAST FOUR PERIODS. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... MAIN CONCERN IN THIS TERM WILL BE THE WINDS FOR FRIDAY. MUCH COLDER AIR WILL BE MOVING INTO THE REGION ON FRIDAY W/NW WINDS KICKING IN. MODEL SOUNDINGS SHOW INVERTED V W/MOISTURE LIMITED BETWEEN 850-700MBS. MOMENTUM TRANSFER INDICATES WIND GUST POTENTIAL OF 35 TO 40 MPH DURING THE DAY W/THE HIGHEST GUSTS OVER THE HIGHER TERRAIN. THE NAM AND GFS BOTH SUPPORT THIS POTENTIAL. GIVEN THAT SUNSHINE WILL BE AVAILABLE EARLY TO ALLOW FOR SOME HEATING IN THE BLYR, GUSTY WINDS ARE POSSIBLE. THEREFORE, DECIDED TO BUMP THE GUSTS FOR FRIDAY. CAA UNDERWAY COMBINED W/THE WINDS WILL MAKE IT FOR A COLD DAY W/DAYTIME MAXES STRUGGLING TO GET OUT OF THE LOWER 40S ACROSS THE NORTH AND WEST. CENTRAL AND AND DOWNEAST AREAS SHOULD SEE SOME DOWNSLOPING TO ALLOW FOR UPPER 40S TO LOWER 50S. THE WINDS WILL SUBSIDE FRIDAY NIGHT AS THE GRADIENT RELAXES AND SKIES CLEAR OUT. WINDS LOOK LIKE AS THOUGH THEY WILL STAY UP ENOUGH TO ALLOW FOR SOME MIXING IN THE BLYR. THIS IN TURN WILL KEEP OVERNIGHT TEMPERATURES FROM BOTTOMING OUT BELOW THE MID 20WS AS IT LOOKS ATTM. HIGH PRES IS FORECAST TO RIDGE ACROSS THE CWA FROM THE S ON SATURDAY W/A CONTINUED CHILLY AIRMASS. DAYTIME MAXES ARE EXPECTED TO BE IN THE LOW TO MID 40S ACROSS THE NORTHERN 1/2 OF THE CWA W/UPPER 40S TO AROUND 50 CENTRAL AND DOWNEAST. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... A RATHER ACTIVE PATTERN TO CONTINUE FOR THIS TERM. HIGH PRES WILL PASS OFF TO THE E ON SATURDAY NIGHT WHICH WILL ALLOW FOR A RETURN FLOW TO SET UP IN ADVANCE OF AN APPROACHING FRONTAL SYSTEM. OVERNIGHT TEMPERATURES WILL DROP OFF QUICKLY SATURDAY EVENING AND THEN SHOULD LEVEL OFF AS CLOUDS MOVE AFTER MIDNIGHT. SUNDAY WILL SEE CLOUDS AND A ROUND OF SHOWERS MOVING INTO THE CWA AS LOW PRES MOVES THROUGH QUEBEC BRINGING A FRONTAL BOUNDARY ACROSS THE REGION. DECIDED TO BRING POPS UP TO 70% ACROSS THE NORTHERN 1/2 OF THE CWA AND STAYED W/CHANCE POPS(40-50%) FOR THE REST OF THE REGION. THIS SYSTEM IS A FAST MOVER AND SHOWERS SHOULD END AFTER MIDNIGHT. A SLIGHT COOLDOWN IS FORECAST ON MONDAY BUT TEMPERATURES ABOVE NORMAL FOR EARLY NOVEMBER. HIGH PRES IS FORECAST TO SLIDE S OF THE CWA ON TUESDAY W/DRY WEATHER. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... NEAR TERM: EXPECT IFR CONDITIONS TODAY THEN IMPROVING TO VFR CONDITIONS LATER TONIGHT. SHORT TERM: MVFR CIGS FRIDAY MORNING ACROSS THE NORTHERN TERMINALS. OTHERWISE, VFR INTO SATURDAY FOR ALL TERMINALS. CONDITIONS ARE EXPECTED TO DROP TO MVFR ON SUNDAY W/SOME SHRA POSSIBLE. && .MARINE... NEAR TERM: WILL USE THE NAM12 FOR SUSTAINED WINDS TODAY AND TONIGHT. WILL KEEP GALE WARNING IN PLACE INTO THIS AFTERNOON. WINDS MAY DIMINISH LATER TODAY THEN INCREASE TONIGHT IN COLD ADVECTION BEHIND COLD FRONT. FOR WAVES: A SOUTHEASTERLY FETCH IS CURRENTLY DEVELOPING FROM THE NEW ENGLAND COAST SOUTHWARD.THIS FETCH WILL CONTINUE TO BUILD INTO EARLY AFTERNOON THEN WILL BE BROKEN UP BY WIND SHIFT TOWARDS EVENING. EXPECT MAXIMUM WAVE HEIGHTS TO BUILD TO AROUND 18 FEET/10-12 SECONDS BY THIS AFTERNOON. WILL USE NEAR SHORE WAVE MODEL WITH WAVE WATCH III FORCING TO POPULATE WAVE GRIDS. SHORT TERM: A STRONG SMALL CRAFT ADVISORY EXPECTED FOR SATURDAY W/NW WINDS KICKING IN. SUSTAINED WINDS OF 20-25 KT W/GUSTS TO AROUND 30. GUSTS COULD APPROACH 35 KTS FOR A FEW HRS ON FRIDAY W/THE COLD FRONT PASSAGE. WAVE HEIGHTS WILL BEGIN TO SUBSIDE DURING THE DAY. CONDITIONS ARE FORECAST TO IMPROVE FRIDAY NIGHT INTO SATURDAY W/WINDS DROPPING BELOW 20S KTS AND WAVE HEIGHTS DROPPING BACK BELOW 6 FT. HIGH PRES IS FORECAST TO RIDGE ACROSS THE WATERS ON SATURDAY W/WINDS BECOMING LIGHT AND WAVES DROPPING OFF BELOW 3 FT. CONDITIONS ARE EXPECTED TO STAY BELOW SMALL CRAFT ADVISORY LEVELS INTO MONDAY. && .TIDES/COASTAL FLOODING... 105 PM UPDATE...HIGH TIDE HAS ARRIVED AND WE HAVE HAD REPORTS OF MINOR COASTAL FLOODING IN MACHIAS AND SOME OVERWASH ON SEAWALL ROAD. THE BANGOR RIVER GAGE APPEARS TO HAVE CRESTED AND REMAINED BELOW 11 FT. WILL KEEP THE COASTAL FLOOD ADVISORY GOING FOR AT LEAST A COUPLE MORE HOURS BUT IT SHOULDN`T BE WARRANTED BEYOND THAT. PREVIOUS DISCUSSION...PRIMARY CONCERN CONTINUES TO BE COINCIDENCE OF SPRING TIDE WITH STORM SURGE AND LARGE/LONG PERIOD WAVES RESULTING FROM ONGOING STORM SYSTEM. NEXT HIGH TIDE AT 12:33 PM TODAY STILL APPEARS TO COINCIDE WITH LARGEST AND LONGEST PERIOD WAVES WITH OFF-SHORE WAVE HEIGHTS BETWEEN 16 AND 20 FEET AND PERIODS OF 10 TO 12 SECONDS. WAVES APPROACHING COAST NOW EXPECTED TO TO TOP OFF AT AROUND 15 FEET. EXPECT OVERTOPPING AT DEER ISLE CAUSEWAY... SEAWALL ROAD... SCHOODIC POINT... WINTER HARBOR NEAR THE TIME OF HIGH TIDE TODAY. ALSO STRONG WIND FORCING ACROSS PENOBSCOT AND MACHIAS BAYS COMBINED WITH SPRING TIDE COULD RESULT IN TIDAL FLOODING IN MACHIAS AND BANGOR. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...COASTAL FLOOD ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR MEZ029-030. MARINE...GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR ANZ050>052. && $$ NEAR TERM...HASTINGS/MIGNONE SHORT TERM...HEWITT LONG TERM...HEWITT AVIATION...HASTINGS/MIGNONE/HEWITT MARINE...HASTINGS/MIGNONE/HEWITT TIDES/COASTAL FLOODING...HASTINGS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
419 PM CDT THU OCT 29 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 419 PM CDT THU OCT 29 2015 STRONG LOW PRESSURE SYSTEM TO OUR EAST IS QUITE IMPRESSIVE AND WE REMAIN UNDER THE LARGE LOW CLOUD DECK ASSOCIATED WITH THIS SYSTEM. MEANWHILE...A HIGH PRESSURE AXIS OFF TO OUR WEST/DRAPED ACROSS THE CENTRAL DAKOTAS...WILL CONTINUE PUSHING EAST INTO OUR AREA TONIGHT. SO...THE BREEZY NORTHWEST WINDS WILL CONTINUE THE NEXT FEW HOURS BEFORE TAPERING AROUND DARK. DRIZZLE AND A FEW RAIN SHOWERS WILL CONTINUE THROUGH THE NEXT FEW HOURS ACROSS WESTERN WI. THE RIDGE AXIS WILL WORK THROUGH OUR AREA OVERNIGHT...SO WINDS WILL DROP TO LESS THAN 5 MPH AND TURN SOUTHWESTERLY BY EARLY TOMORROW MORNING ACROSS MOST THE FA. IN TERMS OF CLOUD COVER...THE MAIN CHANGE WAS TO SLOW DOWN THE PROGRESSION OF THE LOW STRATUS TO THE EAST OVERNIGHT...AS THE HRRR AND NAM CONTINUE TO SHOW LOW LEVEL MOISTURE REMAIN IN PLACE DESPITE THE SURFACE RIDGE WORKING THROUGH. WITH THAT...INCREASED OVERNIGHT LOWS SLIGHTLY...BUT THE SOUTHERLY WINDS STILL LOOK TO BE THE MAIN FACTOR FOR THE TEMPS. TOMORROW MORNING WILL BE DRY WITH THE LOW CLOUDS MOVING EAST OF THE AREA THROUGH THE MORNING. HOWEVER...MID AND HIGH LEVEL CLOUDS AHEAD OF AN APPROACHING FRONT WILL QUICKLY FILL IN BEHIND THE LOW LEVEL CLOUDS. BY TOMORROW AFTERNOON...EXPECTING PRECIP TO START BREAKING OUT ACROSS SOUTHWESTERN MN AHEAD OF AN APPROACHING WARM FRONT. CAMS CONTINUE TO INDICATE SHOWERS DEVELOPING ESPECIALLY FROM 21Z-00Z...BUT MOST OF THE PRECIP WILL COME TOMORROW NIGHT /WHICH IS DISCUSSED FURTHER IN THE LONG TERM SECTION OF THIS DISCUSSION/. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 419 PM CDT THU OCT 29 2015 SHOWERS MOVING INTO SW MN LATER FRIDAY AFTERNOON SHOULD SPREAD INTO SOUTH CENTRAL MN AND THEN WESTERN WISC FRIDAY EVENING... ENDING IN WESTERN WISC SATURDAY MORNING...BUT SHORT WAVE ARRIVING FROM THE WNW WILL BRING A CHANCE SATURDAY AFTERNOON AND EVENING OVER EAST CENTRAL MN INTO NWRN WISC. FOR FRIDAY EVENING...MODEST STRENGTH MID LEVEL LOW FROM THE SW STATES WILL BE IN THE CENTRAL PLAINS...WITH MOISTURE STREAMING NEWD AND SIDESWIPING MN/WI. GREATEST RAINFALL TOTALS WILL EXTEND FROM SOUTH CENTRAL MN INTO WISC FRIDAY EVENING INTO SATURDAY MORNING. THEN SHORT WAVE ARRIVES FROM THE WNW SATURDAY AFTERNOON... WITH THE BEST LIFT MOVING ACROSS NORTHERN MN INTO NORTHERN WISC. IT WILL BE SOMEWHAT STARVED FOR LOW LEVEL MOISTURE AND SMALLER POPS ARE IN ORDER AS FAR SOUTH AS EAST CENTRAL MN AND MOST OF OUR WISCONSIN AREA...THIS IS FOR SATURDAY AFTERNOON INTO SATURDAY EVENING. NEXT LITTLE LOW SUNDAY NIGHT FROM THE WNW LOOKS MUCH TO WEAK TO RESULT IN ANYTHING MORE THAN SOME CLOUDS. THIS SHORT WAVE SUNDAY NIGHT WILL BE EMBEDDED WITH INCREASINGLY ZONAL FLOW ON MONDAY...AND MODELS POINT TO A BROAD AREA OF MID AND HIGH LEVEL CLOUDS STREAMING ACROSS MN/WI. THUS WILL NEED TO HOLD TO MAX TEMPS FOR MONDAY THAT ARE IN THE CURRENT FORECAST. HOWEVER...LARGE WESTERN TROUGH INTENSIFIES AND EXTENDS SOUTHWARD...WITH PART OF THE ENERGY SINKING SOUTHWARD TO SOUTHERN CALIFORNIA. THIS WILL SET UP A BROAD AREA OF SW UPPER FLOW HEADING FOR THE UPPER MIDWEST. TEMPS SHOULD RISE WELL INTO THE 60S...AND THERE ARE EVEN SOME HINTS OF SOME 70 DEGREE READINGS TUESDAY OR WEDNESDAY. HAVE BUMPED UP THE MAX TEMPS A LITTLE FOR TUE-WED. AS THIS OCCURS.. MOISTURE WILL ONCE AGAIN BE ABLE TO STREAM NORTHWARD... AND A COUPLE OF EMBEDDED SHORT WAVES SUGGEST MORE RAIN IS IN THE OFFING FOR TUESDAY NIGHT INTO THURSDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1249 PM CDT THU OCT 29 2015 AS WE REMAIN UNDER THE BACK SIDE OF A STRONG LOW PRESSURE SYSTEM...WE CAN EXPECT THE LOW STRATUS AND BREEZY NORTHWEST WINDS TO CONTINUE THROUGH THE DAY. THE MAIN CHANGE TO THE TAF PACKAGE WAS TO DELAY THE VFR CONDITIONS ARRIVING TOMORROW...MEANING THE STRATUS WILL LINGER A COUPLE EXTRA HOURS. TAFS HAVE BEEN UPDATED WITH THE LATEST THINKING. FOR NOW...CONTINUED MVFR IN THE EAST...AND IFR IN THE WEST WITH CIGS GRADUALLY LIFTING THIS AFTERNOON...BUT DROPPING BACK DOWN OVERNIGHT. WIDESPREAD IFR IS A POSSIBILITY OVERNIGHT DESPITE THE HIGH PRESSURE RIDGE PUSHING IN FROM THE WEST AS LOW LEVEL MOISTURE BECOMES TRAPPED. WILL START SEEING SCATTERING OF THE CLOUDS IN WESTERN MN OVERNIGHT...AND SLOWLY PROGRESSING EAST THROUGH THE DAY TOMORROW...BUT ANOTHER SYSTEM WILL BRING MID AND HIGH CLOUDS ON THE HEELS OF THIS STRATUS DECK. KMSP...CONFIDENCE IS INCREASING THAT WE WILL KEEP THE CEILING ABOVE 017 THROUGH THE AFTERNOON...DESPITE THE RAP...HRRR...AND GFS LAMP GUIDANCE. THE NAM IS AGREEMENT WITH THE TAF...JUST ENOUGH SURFACE HEATING TO LIFT THE CEILING CLOSE TO 020-025 AND HOLD IT THERE UNTIL LATE TONIGHT WHEN IT WILL LIKELY FALL BACK BELOW 017. FINALLY GO VFR TOMORROW MORNING...BUT THAT MAY NOT OCCUR UNTIL CLOSER TO 15Z. /OUTLOOK FOR KMSP/ FRI NIGHT...VFR/-SHRA LIKELY OVERNIGHT. WIND S-SW 10KTS. SAT...CHC MORNING MVFR/SHRA. VFR AFTN. WIND SW 5-10KTS. SUN...VFR. WIND WEST BECMG SW 5-10KTS. MON...VFR. WIND S 5-10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. && $$ SHORT TERM...SPD LONG TERM...TDK AVIATION...SPD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
320 PM EDT THU OCT 29 2015 .SYNOPSIS...A COLD FRONT WILL CROSS CENTRAL NC LATE TODAY AND THIS EVENING. CANADIAN HIGH PRESSURE WILL BUILD ACROSS THE EASTERN U.S. TONIGHT THROUGH FRI NIGHT...SETTLING OVERHEAD ON SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 320 PM THURSDAY... A BAND OF MID-HIGH LEVEL CLOUDS ASSOCIATED WITH A A S/W AND ITS ATTENDANT SFC FRONT HAVE ADVANCED AS FAR EAST AS THE HIGHWAY 1 CORRIDOR. THIS BAND OF CLOUDS WILL CONTINUE TO PROGRESS EAST THROUGH THE REMAINDER OF THE AFTERNOON. WHERE SKIES ARE BROKEN- OVERCAST...TEMPERATURES WERE IN THE 60S TO AROUND 70. CONVERSELY WHERE MOSTLY-PARTLY SUNNY SKIES PREVAIL...TEMPERATURES IN THE MID- UPPER 70S WERE COMMON...APPROACHING 80 IN THE FAR SE. IN SPITE OF THE LIFT ALOFT ASSOCIATED WITH SPEED CONVERGENCE...LITTLE IN THE MANNER OF SHOWERS OCCURRING WITH THE FRONT ACROSS THE SOUTHERN APPALACHIANS. LATEST MESO-ANALYSIS STILL DEPICTS MODEST LOW LEVEL MOISTURE ADVECTION INTO OUR SOUTHERN PIEDMONT AND SANDHILLS. CAM AND HRRR REFLECTIVITY SIMULATIONS VERIFYING TOO WET AT 18Z...AND THIS PIECE OF GUIDANCE STILL DEPICTING ISOLATED-SCATTERED LIGHT RAIN SHOWERS TRAVERSING CENTRAL NC WEST-TO EAST THIS EVENING. BASED ON BEST LOW LEVEL ADVECTION INTO OUR SW COUNTIES...PLAN TO RETAIN A SLIGHT CHANCE POP ACROSS THE SW COUNTIES...AND EXTENDING INTO THE SANDHILLS. PLAN TO MAINTAIN MENTION OF A FEW SPRINKLES ACROSS THE NORTH. S/W AND SFC COLD FRONT WILL CROSS THE REGION THIS EVENING. THE SFC FRONT SHOULD EXIT OUR EASTERN COUNTIES BY OR SHORTLY AFTER MIDNIGHT...WITH CLEARING SKIES WEST-EAST COMMENCING IN THE WEST AROUND 9 PM...AND INTO THE COASTAL PLAIN AFTER MIDNIGHT. MIN TEMPS VARY FROM THE MID 40S NW TO THE LOWER 50S SE WHERE CLOUDS THROUGH THE EVENING INTO THE OVERNIGHT WILL HOLD TEMPS UP COMPARED TO THE WESTERN PIEDMONT. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 320 PM THURSDAY... FRIDAY AND FRIDAY NIGHT...S/W RIDGE OVER THE DEEP SOUTH WILL TRANSLATE EAST AS SFC HIGH BUILDS INTO THE REGION. THIS WEATHER SYSTEM WILL BRING MOSTLY CLEAR SKIES AND SEASONABLY COOL TEMPS. MAX TEMPS FRIDAY AFTERNOON MID-UPPER 60S. WITH THE SFC RIDGE IN OUR VICINITY FRIDAY NIGHT...EXPECT DECENT NOCTURNAL RADIATIONAL CONDITIONS. MIN TEMPS IN THE UPPER 30S-LOWER 40S EXPECTED WITH MID 30S PROBABLE IN THE NORMALLY COLDER LOCATIONS. SFC AND S/W RIDGE DRIFT EWD SATURDAY...INITIATING A RETURN FLOW REGIME ACROSS CENTRAL NC. INCREASING MOISTURE THROUGH THE COLUMN COUPLED WITH AN APPROACH OF A S/W WILL INCREASE MID-HIGH LEVEL CLOUDS FROM THE WEST...BEGINNING EARLY SATURDAY AFTERNOON IN THE WEST...OVERSPREADING MOST OF THE REGION BY SUNSET. ISENTROPIC LIFT BEGINS TO INCREASE AFTER SUNSET SATURDAY NIGHT AND BECOMES SUFFICIENT ENOUGH TO WARRANT A CONTINUATION OF SLIGHT CHANCE POPS AFTER MIDNIGHT IN THE WEST. HIGH TEMPERATURES SATURDAY DEPENDENT ON EXTENT/OPAQUENESS OF HIGH CLOUDS. CONSIDERING THAT TEMPS WILL BE STARTING NEAR 40-LOWER 40S...AN EARLIER THAN ANTICIPATED ARRIVAL OF THE THICKER CLOUDS COULD DETER TEMP RECOVERY. THIS MAY RESULT IN MAX TEMPS AS MUCH AS 5- 6 DEGREES COOLER THAN CURRENTLY FORECAST...ESPECIALLY IN THE WEST. FOR NOW WILL STICK WITH CONSENSUS GUIDANCE OF LOW-MID 60S WEST TO MID-UPPER 60S EAST. NOT AS COOL SATURDAY NIGHT WITH A MILDER AIR MASS ENVELOPING THE REGION. MIN TEMPS IN THE UPPER 40S-LOWER 50S. && .LONG TERM /SUNDAY THROUGH THURSDAY/... AS OF 205 PM WEDNESDAY... RETURN FLOW AND MOISTURE TRANSPORT AROUND HIGH PRESSURE OFFSHORE WILL FURTHER PROMOTE INCREASING CLOUDINESS ON SUNDAY. MEANWHILE...AN APPROACHING S/W TROUGH IN THE SOUTHERN STREAM ALONG WITH ITS SFC WARM FRONT AND LOW PRESSURE WAVE WILL LIFT NORTH FROM THE DEEP SOUTH ON SUNDAY AND MOVE INTO AND ACROSS CENTRAL NC LATE SUNDAY INTO MONDAY MORNING. AS SUCH...EXPECT INCREASING RAIN CHANCES FROM WEST TO EAST DURING THE DAYTIME SUNDAY WITH THE HEAVIEST RAIN EXPECTED SUNDAY EVENING THROUGH SUNDAY NIGHT AS THE LOW PRESSURE WAVE MOVES ACROSS. ITS WORTH NOTING THAT THE LATEST GFS PATTERN FOR THE PERIOD VALID DURING SUNDAY EVENING...WHICH FEATURES A WARM FRONT LIFTING NORTH QUICKLY FOLLOWED BY A LOW PRESSURE WAVE...ALONG WITH THE NOSE OF A 50+ KT LLJ COUPLED WITH 50+ KT OF 0-6KM BULK SHEAR...ALL SUGGESTS THE POTENTIAL FOR SUPERCELLS DURING THAT TIME. THERE`S STILL PLENTY OF TIME FOR THE PATTERN TO CHANGE...BUT DEFINITELY WORTH KEEPING TABS ON AS WE HEAD THROUGH THE NEXT FEW DAYS. THEN ON MONDAY...A FEW LINGERING SHOWERS WILL BE POSSIBLE THROUGH EARLY AFTERNOON UNTIL THE UPPER TROUGH AXIS MOVES ACROSS...THEN EXPECT IMPROVING CONDITIONS WITH DECREASING CLOUDINESS BEGINNING LATE MONDAY AS THE TROUGH AXIS MOVES EAST AND S/W RIDGING BEGINS TO BUILD IN FROM THE WEST. FAIR WEATHER THEN EXPECTED DURING THE MIDWEEK PERIOD AS AN UPPER RIDGE BUILDS ACROSS THE SOUTHEAST. ABOVE NORMAL TEMPS WILL CONTINUE THROUGH THE PERIOD WITH NO SIGNIF AIRMASS CHANGES. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... AS OF 150 PM THURSDAY... A SURFACE COLD FRONT WILL APPROACH FROM THE WEST THIS AFTERNOON AND CROSS CENTRAL NC THIS EVENING. THIS FEATURE WILL PRODUCE A BAND OF CLOUDS WITH BASES VARYING BETWEEN 4000-8000FT. THERE APPEARS TO BE ENOUGH FORCING FOR AT LEAST A FEW SPRINKLES....ESPECIALLY SOUTH OF HIGHWAY 64...WITH A FEW SHOWERS POSSIBLE NEAR KFAY EARLY THIS EVENING. THE FRONT WILL EXIT OUR REGION AROUND MIDNIGHT. NLY FLOW BEHIND THE FRONT WILL USHER A COOLER AND DRIER AIR MASS INTO CENTRAL NC...ASSOCIATED WITH A CANADIAN HIGH PRESSURE SYSTEM. THIS WEATHER SYSTEM WILL INITIATE A PERIOD OF VFR CONDITIONS THAT SHOULD LAST THROUGH LATE SATURDAY. AN AREA OF LOW PRESSURE WILL ADVANCE FROM THE WEST-SW SUNDAY AND CROSS CENTRAL NC SUNDAY NIGHT THROUGH MONDAY. THIS WEATHER SYSTEM MAY BRING A PERIOD OF MVFR/IFR CONDITIONS DUE TO CEILINGS AND RAIN SHOWERS. AVIATION CONDITIONS ARE EXPECTED TO SLOWLY IMPROVE TUESDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...WSS/26 NEAR TERM...WSS SHORT TERM...WSS LONG TERM...RAH AVIATION...WSS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
319 PM CDT THU OCT 29 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 314 PM CDT THU OCT 29 2015 ISSUE TONIGHT IS CLOUD TRENDS. FOR THE MOST FOLLOWED THE SLOWER CLEARING TREND OF THE HRRR MODEL ITS 925 MB RH FIELD. IT SHOWS THE MAIN CLEARING WAITING TIL 06Z OR LATER TO REACH THE RRV. THAT SAID THERE IS A HOLE IN THE CLOUDS NOW APPEARING QUITE QUICKLY JAMESTOWN AREA INTO COOPERSTOWN. THIS CLOUD AREA MAY CLEAR OUT MORE AND THIS MAY ACCELERATE CLEARING A LOT FASTER THAN CURRENT GRIDS HAVE. IF SKIES CLEAR OUT MORE THAN TEMPS WILL BE A TAD LOWER FOR LOWS AS WELL. FRIDAY WILL SEE A MIX OF CLOUDS AND SUN AS MID AND HIGH LEVEL MOISTURE MOVES IN FROM THE WEST SOUTH OF A SHORT WAVE MOVING THRU SOUTHERN CANADA. KEPT THE AREA DRY WITH MODELS INDICATING PRECIP JUST NORTH OF THE INTL BORDER. MILD ON FRIDAY WITH HIGHS IN THE 50S. FRIDAY NIGHT WILL SEE SOME CLEARING WORK IN BEHIND THAT SHORTWAVE. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 314 PM CDT THU OCT 29 2015 FAST MOVING SHORT WAVES/SFC LOWS WILL MOVE NEAR THE INTL BORDER SATURDAY AND AGAIN SUNDAY. THIS WILL GIVE FAST MOVING AREAS OF RAIN SHOWERS TO NORTHERN PARTS OF THE FCST AREA...BEST CHANCE MIDDAY SATURDAY NE ND AND AFTN IN NW MN. THEN ANOTHER CHC SUNDAY. BOTH AREA PRETTY LIGHT EVENTS. QUITE MILD AGAIN WITH HIGHS LOWER 50S NORTH TO LOWER 60S SOUTH WHERE SOME SUN IS LIKELY. SUNDAY NIGHT THROUGH WEDNESDAY...MODELS IN GENERAL AGREEMENT AND CONTINUE TO SHOW UPPER LEVEL FLOW BECOMING MORE SOUTHWESTERLY. PLACEMENT OF SFC FEATURES SHOW PCPN OVER THE AREA IN THE EARLY PART OF THE PERIOD...WITH PCPN MAINLY ACROSS THE NRN PORTION OF THE AREA. INDICATIONS ARE FOR A MORE ORGANIZED SYSTEM BY THE END OF THE PERIOD AND MORE WIDESPREAD LIGHT PCPN...MAINLY IN THE FORM OF RAIN. SOME LIGHT SNOW MAY MIX IN...BUT THICKNESS VALUES INDICATE MORE OF A RAIN SCENARIO ATTM. OTHERWISE...TEMPERATURES ARE EXPECTED TO BE NEAR...TO SLIGHTLY ABOVE...NORMAL HEADING INTO NOVEMBER. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1253 PM CDT THU OCT 29 2015 MAIN CHALLENGE WILL BE CIGS THRU THE PERIOD. ABUNDANT LOW LEVEL MOISTURE IS HANGING TOUGH AND WILL PERSIST UNTIL THE SFC RIDGE AXIS FINALLY MOVES E. DRYING IS INDICATED IN THE LOW LEVELS...BUT WILL BE SLOWLY MOVING FROM THE DVL BASIN ACROSS THE REST OF THE AREA THRU THE PERIOD...THUS TIMED THE CHANGES IN THE TAFS ACCORDINGLY. WILL HAVE TO CONTINUE MONITORING FOR SIGNIFICANT CHANGES AND AMEND AS NEEDED. OTHERWISE...WINDS WILL CONTINUE TO DECREASE THRU THE AFTERNOON HOURS...AND BECOME SRLY ACROSS THE AREA BY 12-15Z. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...RIDDLE LONG TERM...HOPKINS/RIDDLE AVIATION...HOPKINS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1259 PM CDT THU OCT 29 2015 .UPDATE... ISSUED AT 1253 PM CDT THU OCT 29 2015 CLOUDS HOLDING STRONG WITH CLEARING LIKELY TIED TO NEAR THE SFC RIDGE AXIS. PER HRRR THE LOW LEVEL RH REMAINS INTO THE NIGHT WITH CLEARING PSBLY INTO PARTS OF THE RRV MORE TOWARD 06Z. CLOUDS AND TEMP GRIDS LOOKING GOOD SO NO FURTHER CHANGES FOR THIS AFTN PD. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 258 AM CDT THU OCT 29 2015 THE LATEST EVENT IS SLOWLY WINDING DOWN WITH THE MAIN FORECAST CHALLENGE SHIFTING TO HOW FAST CLOUDS MAY ERODE TODAY. AS FOR NOW IT REMAINS SOCKED IN WITH CLOUDS AND GUSTY NW WINDS. RADAR STILL SHOWS SOME WEAKER ECHOES OVER THE FAR EAST AND SE. 925MB TEMPS THERE ARE ABOVE ZERO AND SFC TEMPS ARE CLIMBING BACK TO AROUND 40F...SO WILL KEEP PCPN TYPE IN LIQUID FORM UNTIL DAYBREAK WHEN THE PCPN SHOULD BE ABOUT DONE. THE GUSTY NW WINDS WILL HOLD UP THRU THE MORNING AND FINALLY BEGIN TO RELAX THRU THE AFTERNOON. CLOUDS ARE A TOUGH CALL BUT WILL STICK WITH THE IDEA OF CLOUDY THRU THE MORNING AND SOME DECREASE THRU THE AFTERNOON WEST OF THE RED RIVER. NOT MUCH RISE IN TEMPS TODAY UNLESS THE CLOUDS CLEAR OUT SOONER. WINDS WILL SWITCH AROUND TO THE SOUTH TONIGHT WITH 850MB WARM ADVECTION WHICH COULD BRING A FEW MORE MID LEVEL CLOUDS WITH IT. WARMING TREND INTO FRIDAY WITH SW-W WINDS. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 258 AM CDT THU OCT 29 2015 GOING TO STICK WITH A DRY FORECAST FRI NIGHT AS NEARLY ALL MODEL SOLUTIONS KEEP IT JUST TO THE NORTH OR EAST OF THE FA. NEXT CHANCE OF RAIN SHOULD ARRIVE SAT MORNING IN THE WESTERN HALF OF THE FA THEN SPREADING EAST THRU THE AFTERNOON. BEST PCPN CHANCES REMAIN CLOSER TO THE CANADIAN BORDER. SOME OF THIS LIGHT PCPN MAY LINGER INTO SAT NIGHT AROUND THE LAKE OF THE WOODS REGION. SUNDAY THROUGH WEDNESDAY...MEDIUM RANGE MODELS ARE IN VERY GOOD AGREEMENT ON NEAR ZONAL FLOW BECOMING MORE SOUTHWESTERLY ALOFT AS A SPLIT TROUGH DIGS INTO THE WESTERN CONUS. THEY DIFFER ON THE DETAILS...PARTICULARLY THE TIMING OF ANY WEAK LEAD OR NORTHERN BRANCH SHORTWAVES COMING OUT INTO THE PLAINS. BLENDED SOLUTION GIVES US SOME LOW POPS SUNDAY THROUGH TUESDAY...MAINLY IN THE NORTHERN COUNTIES AND GIVEN THE POSSIBILITY OF WEAK SHORTWAVES AND A COLD FRONT COMING THROUGH DURING THAT PERIOD IT SEEMS REASONABLE. MORE ROBUST PRECIP IS POSSIBLE AT THE TAIL END OF THE PERIOD AS MODELS COME INTO A BETTER AGREEMENT ON A SFC LOW TRACKING TO OUR SOUTHEAST AND DEFORMATION ZONE PRECIP SETTING UP FOR WEDNESDAY. TEMPS SUNDAY AND MONDAY WILL BE FAIRLY WARM WITH SOME 60S POSSIBLE IN THE SOUTH BUT THE FRONTAL BOUNDARY WILL KNOCK TEMPS ON WEDNESDAY AND THURSDAY BACK DOWN TO NEAR SEASONAL AVERAGES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1253 PM CDT THU OCT 29 2015 MAIN CHALLENGE WILL BE CIGS THRU THE PERIOD. ABUNDANT LOW LEVEL MOISTURE IS HANGING TOUGH AND WILL PERSIST UNTIL THE SFC RIDGE AXIS FINALLY MOVES E. DRYING IS INDICATED IN THE LOW LEVELS...BUT WILL BE SLOWLY MOVING FROM THE DVL BASIN ACROSS THE REST OF THE AREA THRU THE PERIOD...THUS TIMED THE CHANGES IN THE TAFS ACCORDINGLY. WILL HAVE TO CONTINUE MONITORING FOR SIGNIFICANT CHANGES AND AMEND AS NEEDED. OTHERWISE...WINDS WILL CONTINUE TO DECREASE THRU THE AFTERNOON HOURS...AND BECOME SRLY ACROSS THE AREA BY 12-15Z. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...RIDDLE SHORT TERM...GODON LONG TERM...GODON/JR AVIATION...HOPKINS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1234 PM CDT THU OCT 29 2015 .UPDATE... ISSUED AT 1225 PM CDT THU OCT 29 2015 MAIN CHANGES INVOLVE TEMPERATURES THIS AFTERNOON AND CLOUDS. CLOUD COVER HOLDING TEMPERATURES FLAT SO FAR THIS MORNING IN THE UPPER 20S TO AROUND 30 OVER MUCH OF THE NORTHWEST AND CENTRAL. CLOUDS ARE ERODING SOUTHWEST THOUGH. TRIMMED TEMPS AND KEPT CLOUDS IN MOST OF THE AFTERNOON CENTRAL. UPDATE ISSUED AT 937 AM CDT THU OCT 29 2015 CLOUDS APPEAR TO BE SLOW TO CLEAR AGAIN TODAY AS THE STRATUS EXTENDS WEST INTO EASTERN MONTANA THIS MORNING. HRRR MODEL KEEPS CLOUDS WEST OF THE MISSOURI THROUGH 21Z. WILL ADJUST TO MAINTAIN CLOUDS THROUGH THAT TIME. WILL PROBABLY SEE ONLY A 5 TO 10 DEGREE DIURNAL TEMPERATURE CHANGE FROM THIS MORNINGS LOW TO THIS AFTERNOONS HIGH MOST AREAS. BISMARCK RADAR SHOWING LAKE EFFECT SNOW SHOWERS DIMINISHING WITH THE WINDS AND SHOULD COMPLETEY END BY LATE MORNING. UPDATE ISSUED AT 636 AM CDT THU OCT 29 2015 GIVEN TRENDS IN THE 08-10 UTC RAP AND HRRR TIME LAGGED ENSEMBLES WHICH DEPICT A SLOWING CLEARING TREND FROM WEST TO EAST THROUGH THE DAY...INCREASED CLOUD COVER THROUGH THE AFTERNOON AND INTO THE EARLY EVENING CENTRAL. ALSO...ADDED POPS FOR LAKE SAKAKAWEA EFFECT SNOW SHOWERS SOUTH CENTRAL THIS MORNING. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 321 AM CDT THU OCT 29 2015 MAINLY QUIET WEATHER TODAY. MAIN CONCERN IS TIMING OF EROSION OF CLOUDS FROM WEST TO EAST AFFECTING THE TEMPERATURE FORECAST. THE STRONG LOW PRESSURE SYSTEM ASSOCIATED WITH THE GUSTY NORTHWEST WINDS AND SNOW SHOWERS ON WEDNESDAY WAS OVER THE GREAT LAKES AREA THIS MORNING...WITH THE ASSOCIATED CLOUD SHIELD SURROUNDING THE LOW EXTENDING WESTWARD ACROSS MANITOBA AND SASKATCHEWAN AND THE DAKOTAS. A WEAK UPPER LEVEL RIDGE WAS OVER THE FRONT RANGE...UPSTREAM FROM THE NEXT UPPER LEVEL LONGWAVE TROUGH DEVELOPING OVER THE WEST COAST. A WEAK SURFACE RIDGE AXIS EXTENDED FROM SASKATCHEWAN SOUTHWARD TO THE ND/MT AND WY/SD BORDERS. THE NORTHWEST WINDS HAD DECREASED GREATLY OVER WESTERN NORTH DAKOTA...WITH WINDS OF 5 TO 10 MPH REPORTED IN THE FAR WEST. THE NORTHWEST WINDS IN THE TURTLE MOUNTAINS THROUGH THE JAMES RIVER VALLEY WERE STILL BRISK AT AROUND 20 MPH AND GUSTING TO AROUND 30 MPH. THE GREAT LAKES LOW PRESSURE SYSTEM IS FORECAST TO CONTINUE MOVING EAST...AND THE UPPER LEVEL SHORTWAVE RIDGE AXIS OVER THE FRONT RANGE AND ITS ASSOCIATED SURFACE RIDGE AXIS IS PROGGED TO MOVE INTO THE DAKOTAS THIS AFTERNOON. EXPECT THE NORTHWEST WINDS OVER CENTRAL NORTH DAKOTA TO BECOME LIGHT THIS AFTERNOON...WITH WINDS IN THE WEST BECOMING SOUTHERLY. THE LOW CLOUDS SHOULD DISSIPATE FROM WEST TO EAST TODAY...WITH SOME LINGERING FLURRIES IN CENTRAL NORTH DAKOTA EARLY THIS MORNING. LOOK FOR HIGHS FROM THE MID 40S IN THE SOUTHWEST...WITH TEMPERATURES REMAINING IN THE MID 30S IN THE TURTLE MOUNTAINS WHERE CLOUDS WILL LIKELY NOT DISSIPATE UNTIL LATER THIS AFTERNOON. TONIGHT THE NEXT UPPER LEVEL LONGWAVE TROUGH MOVES EAST ACROSS THE ROCKIES...WITH SURFACE LOW PRESSURE DEVELOPING OVER THE FRONT RANGE. MAINLY CLEAR SKIES TONIGHT ACROSS THE FORECAST AREA...BUT MID CLOUDS MOVING INTO THE WEST LATE. LOWS TONIGHT SHOULD BE IN THE UPPER 20S IN THE CENTRAL...TO THE LOWER 30S WEST. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 321 AM CDT THU OCT 29 2015 A CLIPPER SYSTEM ON SATURDAY AND POTENTIALLY UNSETTLED WEATHER MID NEXT WEEK HIGHLIGHTS THE EXTENDED FORECAST. THE 00 UTC DETERMINISTIC SUITE IS IN AGREEMENT ON A CLIPPER SYSTEM TO IMPACT WESTERN AND CENTRAL NORTH DAKOTA SATURDAY MORNING AND INTO THE AFTERNOON. A CHANCE OF RAIN...POSSIBLY MIXED WITH SNOW IN THE MORNING...IS EXPECTED FOR MUCH OF THE AREA...WITH DRY CONDITIONS FORECAST BY EVENING. THERE IS SOME DISAGREEMENT REGARDING THE POTENTIAL STRENGTH OF THE WINDFIELD IN THE WAKE OF THE CLIPPER THROUGH THE AFTERNOON WITH THE 00 UTC GFS THE STRONGEST RESULTING FROM THE DEEPEST SURFACE LOW. THEREAFTER...THE 00 UTC SUITE IS IN AGREEMENT ON A LONGWAVE UPPER LEVEL TROUGH POTENTIALLY DEVELOPING ACROSS THE WESTERN CONUS BY EARLY TO MID NEXT WEEK. THIS IS A FAVORABLE PATTERN FOR POSSIBLY WET AND UNSETTLED WEATHER FOR THE NORTHERN PLAINS. WHILE MUCH UNCERTAINTY REMAINS...TRENDS OVER THE COMING DAYS FOR THIS PERIOD WILL HAVE TO BE MONITORED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1225 PM CDT THU OCT 29 2015 FOR THE 18Z TAF PERIOD...LARGE AREA OF STRATUS OVER NORTHWEST AND CENTRAL NORTH DAKOTA WILL SLOWLY ERODE THIS AFTERNOON AND EVENING. MVFR CONDITIONS AT KISN-KDIK IMPROVING TO VFR AFTER 20Z...ANDKMOT- KBIS AFTER 00Z...WITH KJMS BECOMING VFR AFTER 03Z. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...JV LONG TERM...AYD AVIATION...WAA
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
335 PM CDT THU OCT 29 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 334 PM CDT THU OCT 29 2015 CLEARING HAS PROGRESSED NORTHWARD QUITE NICELY THIS AFTERNOON AND HAVE ADJUSTED SKY COVER GRIDS ACCORDINGLY. HRRR AND HOP WRF CLOUD COVER PRODUCTS PICKING UP ON THE CLEARING QUITE NICELY AND SHOWS THE CLEARING CONTINUING...BUT PERHAPS STALLING A BIT LATER THIS EVENING FURTHER EAST. LOW TEMPERATURES TONIGHT ARE QUITE TRICKY AND DO NOT HAVE HIGH CONFIDENCE. HARD TO DETERMINE JUST HOW MUCH CLEARING THERE WILL BE FURTHER TO THE EAST. THERE WILL BE A GOOD AMOUNT OF TIME OF CLEAR SKIES AND LIGHT WINDS FROM THE JAMES VALLEY INTO THE WESTERN CWA. ALTHOUGH...MID AND HIGH LEVEL CLOUDS INCREASE LATER TONIGHT AND WINDS ALSO BEGIN TO GO SOUTHERLY AS THE SFC HIGH MOVES EAST. TOUGH TO BALANCE ALL THIS OUT AND GET A GOOD NUMBER FOR LOWS. REGARDLESS THOUGH...LOOKING AT 20S AND LOW 30S FOR MOST LOCATIONS. SYSTEM FOR FRIDAY/FRIDAY EVENING STILL LOOKS TO AFFECT MAINLY SOUTHEAST SD INTO MN AND STILL HAVE JUST SMALL POPS ACROSS THE SOUTHEAST FRINGE OF THE CWA. MAIN STORY FOR THE REST OF THE SHORT TERM PERIOD WILL BE THE WARM UP INTO SATURDAY AS 925/850 MB TEMPS ARE ON THE RISE WITH MILD PACIFIC AIR STREAMING INTO THE REGION. HIGHS WILL RISE INTO THE 60S BY SATURDAY WITH DRY CONDITIONS EXPECTED. .LONG TERM...(SUNDAY THROUGH THURSDAY) ISSUED AT 334 PM CDT THU OCT 29 2015 MID LEVEL WARM AIR ADVECTION BENEATH A MILD ZONAL FLOW ALOFT WILL RESULT IN TEMPERATURES NEARLY 20 DEGREES ABOVE NORMAL SUNDAY. A SOUTH SOUTHWEST MIXING WIND SHOULD EASILY BE ABLE TO TAKE ADVANTAGE OF 850 MB TEMPERATURES RANGING FROM 10 TO 15 DEGREES CELSIUS. A SIMILAR PATTERN PERSISTS THROUGH MONDAY...BEFORE THE UPPER LEVEL FLOW TRANSITIONS BACK TO THE SOUTHWEST AHEAD OF A LONG WAVE TROUGH MOVING OVER THE WESTERN CONUS. A LOW PRESSURE SYSTEM DEVELOPS IN RESPONSE TO A WAVE OF ENERGY THAT KICKS OUT AHEAD OF THE MAIN TROUGH TUESDAY NIGHT/WEDNESDAY. AN ASSOCIATED COLD FRONT IS EXPECTED TO MOVE ACROSS THE REGION WEDNESDAY AFTERNOON...ALTHOUGH QUITE A BIT OF DIFFERENCE IN THE TIMING AND INTENSITY OF THIS FEATURE AMONGST MODEL RUNS. MODELS REALLY BEGIN TO DIVERGE WITH THE EVOLUTION OF THE TROUGH IN THE OUT PERIODS...BUT SLIGHT CHANCE TO CHANCE POPS REMAIN IN THE FORECAST WEDNESDAY THROUGH THURSDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1224 PM CDT THU OCT 29 2015 MAIN AVIATION CONCERNS REVOLVE AROUND AN MVFR STRATUS DECK CURRENTLY SITUATED ACROSS EASTERN SOUTH DAKOTA...AFFECTING THE KABR AND KATY TAF SITES /KMBG CIGS HAVE RISEN INTO VFR CATEGORY/. SATELLITE IMAGERY SHOWS A VERY SLOW EASTWARD MOVEMENT AS WELL AS EROSION ALONG THE WESTERN EDGE OF THE CLOUD DECK...BUT IT WILL STILL BE SEVERAL HOURS BEFORE KABR AND KATY SCATTER OUT. CURRENT ESTIMATES ARE ABOUT 00Z FOR KABR AND 06Z FOR ATY. AFTER CLOUDS CLEAR OUT WINDS WILL SWITCH AROUND TO THE SOUTH. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ SHORT TERM...TMT LONG TERM...SERR AVIATION...SERR
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
317 PM CDT THU OCT 29 2015 .SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...A FRONTAL BOUNDARY JUST NORTH OF THE CWA MAY BE MOVING SLOWLY NORTH...AND COULD BE THE FOCUS FOR SOME OVERNIGHT CONVECTION WEST OF THE AREA AS AN UPSTREAM MID LEVEL TROUGH EDGES CLOSER. THE HRRR IS DEVELOPING CONVECTION WEST TO SOUTHWEST OF THE UPPER VALLEY AND SUBSEQUENTLY MOVES IT EAST INTO THE CWA. HIGHER DEW POINTS TONIGHT WILL BE SUPPORTED BY A MODERATE SOUTHEAST WIND...AND OVERNIGHT LOW TEMPS WILL BE PROPPED UP IN THE MID 70S. THE FAVORABLE DEW POINTS WILL CONTINUE WITH A STRONG SOUTH LLJ OVERNIGHT...AND WILL FEED INTO A DESTABILIZING ATMOSPHERE. FRIDAY...THE WIND MACHINE WILL BE ON FRIDAY DUE TO PRESSURE FALLS OVER WEST TEXAS...WITH BREEZY SOUTHEAST SURFACE WINDS INLAND AND WINDY CONDITIONS NEARER THE COAST. A MARGINAL RISK OF SEVERE WEATHER IS ADVERTISED BY SPC...WITH LOW LEVEL SHEAR FAVORING DAMAGING WIND GUSTS AND WEAK SPIN-UP TORNADOES...IF ANYTHING DOES DEVELOP. HIT AND RUN SHOWERS...AND A FEW STORMS DURING THE DAY...WILL CONTAIN BRIEF DOWNPOURS...BUT WITH PWAT PUSHING ABOVE TWO INCHES AGAIN...COULD SEE A QUICK INCH OF RAIN...BUT TRAINING...ESPECIALLY IN THE AFTERNOON... COULD RESULT IN A COUPLE OF INCHES OR MORE OF RAIN. QUICK MOVEMENT ON THE OTHER HAND COULD LIMIT QPF. FRIDAY NIGHT...INGREDIENTS COME TOGETHER TO SUGGEST A SQUALL LINE POSSIBLY MOVING ACROSS THE AREA. UPSTREAM CYCLOGENESIS TO KICKOFF THE BOUNDARY...LOW LEVEL MOISTURE...MID LEVEL ENERGY AND RIGHT ENTRANCE REGION JET LIFT SHOULD ACHIEVE FAVORABLE TIMING. TWO TO FOUR INCHES OF RAIN WILL POSSIBLE. FREQUENT LIGHTNING AND 50 MPH WIND GUSTS COULD ACCOMPANY A SQUALL LINE...WITH SMALL SPIN-UPS POSSIBLE. BACKGROUND WINDS WILL BE BREEZY FROM THE SOUTHEAST THROUGH THE NIGHT...SHIFTING TO SOUTHWEST AND NORTHWEST LATE...WITH DRY SLOTTING AIR MOVING IN FROM THE WEST EARLY SATURDAY MORNING. .LONG TERM /SATURDAY THROUGH THURSDAY/...A STRONG 500 MB TROUGH AXIS WILL MOVE OVER DEEP SOUTH TX ON SATURDAY MAINTAINING THE THREAT FOR CONV MAINLY DURING THE MORNING AND EARLY AFTERNOON HOURS. THE TROUGH AXIS AND THE ASSOCIATED COLD FRONT WILL MOVE OFFSHORE LATE ON SATURDAY ALLOWING FOR DRIER AND MORE STABLE AIR TO FILTER INTO THE REGION FOR THE REST OF THE WEEKEND. IN THE WAKE OF THIS TROUGH 500 MB AND SURFACE RIDGING WILL REBUILD OVER THE AREA ALLOWING FOR FAIRLY DRY CONDITIONS TO PREVAIL THROUGH THE EARLY PORTION OF NEXT WEEK. ANOTHER VERY LARGE 500 MB CLOSED LOW WILL PUSH INTO THE DESERT SW STATES WITH RIDGING HOLDING IN PLACE OVER THE SOUTHEASTERN STATES AND THE GULF OF MEX. THERE APPEARS TO BE SOME POTENTIAL FOR SOME TROPICAL MOISTURE TO BE ADVECTED IN ON THE SW FLOW ALOFT POSSIBLY INCREASING THE CONV POTENTIAL ONCE AGAIN TOWARDS MIDWEEK. WILL FAVOR THE SLIGHTLY FASTER GFS SOLUTION FOR THE PASSAGE OF THE FIRST TROUGH AXIS AS THE ECMWF TENDS TO HOLD THE TROUGH AXIS BACK A LITTLE FURTHER WEST VERSUS THE GFS. OTHERWISE FOR THE REST OF THE LONGER RANGE PERIOD WILL FAVOR A GENERAL BLEND OF THE GFS AND THE ECMWF TEMPS/POPS. && .MARINE /TONIGHT THROUGH FRIDAY NIGHT/...MARINE CONDITIONS WILL DETERIORATE THROUGH SATURDAY WITH THE APPROACH OF AN UPPER DISTURBANCE AND A COLD FRONT. SOUTHEAST WINDS WILL INCREASE TONIGHT...WITH SMALL CRAFT ADVISORY CONDITIONS POSSIBLE LATE TONIGHT OR EARLY FRIDAY MORNING. WAVE HEIGHTS WILL ALSO BUILD TO AROUND SEVEN FEET ON FRIDAY. SCA CONDITIONS WILL THEN PERSIST THROUGH AND BEYOND THE END OF THE SHORT TERM. SHOWERS AND THUNDERSTORMS WILL ALSO INCREASE IN COVERAGE FRIDAY AND FRIDAY NIGHT. SATURDAY THROUGH TUESDAY...EXPECT THE MARINE CONDITIONS TO START TO CALM DOWN IN THE WAKE OF THE UPCOMING FROPA/MID LEVEL TROUGH PASSAGE SATURDAY. THE PGF WILL BE FAIRLY WEAK HEADING INTO EARLY NEXT WEEK AS WEAK TO MODERATE SURFACE RIDGING PREVAILS OVER THE GULF. HOWEVER AS THE LARGE 500 MB LOW OVER THE DESERT SW LATER NEXT WEEK A SURFACE LOW PRESSURE SYSTEM WILL IN TURN BUILD OVER THE CENTRAL PLAINS STATES WHICH MAY START TO TIGHTEN UP THE PGF INCREASING THE SOUTHERLY FLOW LATER NEXT WEEK POSSIBLE PRODUCING SCEC/MARGINAL SCA CONDITIONS ON AND AFTER WED. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 78 84 78 85 / 10 60 50 70 BROWNSVILLE 77 85 77 86 / 10 60 50 60 HARLINGEN 76 87 77 87 / 10 60 40 60 MCALLEN 77 88 77 87 / 10 60 30 40 RIO GRANDE CITY 76 88 74 87 / 20 50 40 30 SOUTH PADRE ISLAND 80 83 79 84 / 10 50 50 70 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV SHORT TERM...54 LONG TERM...60 GRAPHICAST/UPPER AIR...65
AREA FORECAST DISCUSSION
NWS SEATTLE WA
912 AM PDT THU OCT 29 2015 .SYNOPSIS...SHOWERS WILL DIMINISH TODAY AS AN UPPER TROUGH MOVES EAST OF THE AREA. A STRONG PACIFIC FRONTAL SYSTEM WILL BRING RAINY AND BREEZY WEATHER FRIDAY AND SATURDAY. A COOL UPPER TROUGH WILL CROSS THE REGION ON SUNDAY FOR SHOWERS. A STRONG UPPER RIDGE OFFSHORE WILL BRING DRIER WEATHER EARLY NEXT WEEK. && .SHORT TERM...A WEAK UPPER RIDGE WILL MOVE OVER THE AREA TODAY. SOME SHOWERS WILL LINGER HOWEVER IN MOIST ONSHORE FLOW. THE BEST CHANCES WILL BE OVER THE MOUNTAINS. MOIST ZONAL FLOW WILL DEVELOP FRIDAY AND CONTINUE INTO SATURDAY WITH A FRONTAL SYSTEM DRAPED ACROSS THE REGION FOR WET AND BLUSTERY WEATHER. THE HEAVIER PRECIPITATION LOOKS LIKE IT WILL COME IN TWO WAVES. THE FIRST WAVE WILL BE FRIDAY MORNING. THE SECOND HEAVIER SHOT OF RAIN WILL DEVELOP LATER FRIDAY NIGHT AND CONTINUE INTO SATURDAY. THE HEAVY RAINS WILL END FROM NORTH TO SOUTH SATURDAY AFTERNOON AND EVENING AS THE FRONTAL FEATURE SAGS SOUTH OF THE AREA. MINOR RIVER FLOODING IS POSSIBLE BY SATURDAY OR SATURDAY NIGHT. SEE THE HYDROLOGY SECTION BELOW FOR MORE DETAILS. AN UPPER TROUGH WILL MOVE OVER THE AREA ON SUNDAY FOR COOLER SHOWERY WEATHER. SNOW LEVELS WILL FALL TO 4000 TO 5000 FEET WHICH MEANS THE HIGHER MOUNTAIN PASSES COULD PICK UP A FEW INCHES OF SNOW. SCHNEIDER .LONG TERM...PREVIOUS DISCUSSION...A STRONG UPPER LEVEL RIDGE WILL FORM OVER THE NE PAC EARLY NEXT WEEK WITH NORTHERLY FLOW ALOFT OVER WESTERN WA. A WEAK UPPER LEVEL DISTURBANCE MAY TRACK DOWN FROM THE NORTH FOR A CHANCE OF SHOWERS MONDAY AND MONDAY NIGHT. THE RIDGE WILL THEN SHIFT EAST AND INLAND TUESDAY AND WEDNESDAY FOR DRIER WEATHER. THE NORTHERLY FLOW WILL KEEP TEMPERATURES ON THE COOLSIDE WITH TEMPS A FEW DEGREES BELOW NORMAL. THE RIDGE MAY LINGER OVER THE PAC NW THROUGH THE END OF NEXT WEEK FOR MORE DRY WEATHER. 33 && .AVIATION...AN UPPER LEVEL RIDGE WILL PREVAIL OVER THE REGION TODAY FOR STRONG NLY FLOW ALOFT. CONTD LOW LEVEL ONSHORE FLOW. WIDESPREAD MVFR CIGS THIS MORNING WILL BECOME AREAS OF MVFR CIGS THIS AFTERNOON. THE MTNS WILL BE PARTIALLY OBSCD. KSEA...ANTICIPATE CIGS IN THE 1500 TO 2500 FT RANGE TIL 2100 UTC...WITH VFR CONDITIONS PREVAILING AFTER 2100 UTC. HOWEVER... CIGS WILL LOWER BACK INTO THE MVFR CATEGORY RANGE THIS EVENING. WINDS WILL BE SLY 9-13 KT WITH OCNL GUSTS TO 20 KT TODAY. && .MARINE...LOW LEVEL SOUTHERLY OR ONSHORE FLOW WILL CONTINUE THROUGH TONIGHT. A FRONTAL SYSTEM WILL MOVE ACROSS THE AREA ON FRI...RESULTING IN WIND SPEEDS REACHING SMALL CRAFT ADVISORY CRITERION ACROSS ALL WATERS. ANOTHER...POSSIBLY STRONGER SYSTEM...WILL IMPACT THE AREA ON SATURDAY. FELTON/05 && .HYDROLOGY...PREVIOUS DISCUSSION...A WET PATTERN WILL DEVELOP FRIDAY AND CONTINUE INTO SATURDAY. SNOW LEVELS WILL BE HIGH AND SEVERAL INCHES OF RAIN ARE LIKELY OVER THE OLYMPICS AND WEST SLOPES OF THE CASCADES. MODELS DIFFER A BIT WITH THE DETAILS BUT THE GENERAL IDEA IS THERE WILL BE HYDROLOGICALLY SIGNIFICANT RAIN OVER THE MOUNTAINS DURING THIS PERIOD. MODELS SHOW 5-10 INCHES OF RAIN POSSIBLE OVER A 48-HOUR PERIOD ENDING SATURDAY AFTERNOON. THE FIRST SHOT OF HEAVY RAIN APPEARS TO BE DURING THE FIRST HALF OF FRIDAY...THEN PERHAPS A RELATIVE LULL...FOLLOWED BY ANOTHER ROUND OF HEAVY RAIN LATE FRIDAY NIGHT OR SATURDAY. A HYDROLOGIC OUTLOOK IS IN EFFECT FOR MOST OF THE FORECAST AREA TO HIGHLIGHT THE GENERAL THREAT FOR MINOR FLOODING ON AREA RIVERS BY SATURDAY. .SEW WATCHES/WARNINGS/ADVISORIES... WA...NONE. PZ...SMALL CRAFT ADVISORY ALL WATERS EXCEPT CENTRAL STRAIT. && $$ WWW.WEATHER.GOV/SEATTLE YOU CAN SEE AN ILLUSTRATED VERSION OF THIS DISCUSSION AT WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
Area Forecast Discussion National Weather Service Spokane WA 444 AM PDT THU OCT 29 2015 .SYNOPSIS... Light rain will continue this morning then taper off this afternoon. This break period will end on Friday as a deep fetch of Pacific moisture feeds into the region promoting widespread rain on Friday and into Saturday. Windy and gusty conditions will also develop for a damp and blustery Halloween. Unsettled conditions with occasional wet periods will continue into next week. && .DISCUSSION... Today and tonight...A shortwave trough will bring some light precipitation to the Inland Northwest today. One area of light precipitation is moving across extreme eastern WA and north ID as of 2 am. A second band is just barely holding together as it crosses the deep basin but should regain some organization as it encounters the rising terrain east of the basin. This feature will bring another round of light precipitation to the eastern half of the forecast area later this morning. The HRRR and NAM have tracked the first band well so the near term forecast is leaning heavily toward this guidance. Once the trough axis moves off to the east, scattered rain showers will continue in moist upslope flow into the Idaho Panhandle tonight while the remainder of the forecast area has a brief respite from the wet weather. Friday through Sunday...Wetter and windier conditions will begin on Friday as fire hose of an atmospheric river is aimed at the Pacific Northwest. Snow levels will remain high for Friday and Saturday as the subtropical moisture tap pushes into the forecast area. Persistent warm frontal precipitation will begin on Friday and continue into Saturday. A cold front will bring an end to the steady precip and usher in more scattered showers late Saturday. The timing of this break in the wet weather will be critical to trick-or-treaters who wish to remain dry...or at least not drenched. for Sunday, the upper trough will slide over the region with more scattered valley rain and mountain snow showers. Snow levels could fall as low as 3000 ft with mountain passes collecting some snowfall. More details on this to come in the next day or two. Storm total rainfall from Friday through Sunday will be in the one to two and a half inch range in the Idaho Panhandle and Cascades with a general one third to one half inch in the basin...except a tenth or two in the downslope deep basin area. The rising terrain east of the basin will see a half inch to and inch of rainfall. Winds will be a significant issue starting Friday and lasting through Saturday with gust potential in the well mixed warm sector potentially approaching 40 mph over exposed terrain. Winds will remain blustery through Sunday night. Monday through Thursday...The region will be under cool and unstable northerly flow as the work week begins. This will keep a chance of showers in the forecast but as the base of the trough digs south, the tap into deep Pacific moisture will be lost. Valley rain and mountain snow will be showery in nature with light amounts of precipitation compared to the weekend system. Temperatures will be near seasonal normals. /Kelch && .AVIATION... 12Z TAFS:One band of rain showers is moving into the Idaho panhandle and a second band is moving across the basin as of 11Z. These two features will continue to bring IFR/LIFR conditions to TAF sites other than KEAT and KLWS. Once the second band reaches the ID border around 15Z...conditions will begin to improve with MVFR conditions expected by 18Z. Gusty SW winds will develop this afternoon, mixing out the low ceilings. Winds will subside after 03Z and MVFR ceilings may return. /EK && .PRELIMINARY POINT TEMPS/POPS... Spokane 53 43 55 48 58 46 / 20 10 80 80 80 20 Coeur d`Alene 52 41 52 47 56 46 / 40 20 90 90 90 40 Pullman 56 43 55 47 57 46 / 20 20 80 80 80 50 Lewiston 60 46 61 52 62 50 / 20 20 80 70 70 50 Colville 52 39 52 42 54 42 / 80 10 80 80 80 20 Sandpoint 51 39 51 42 54 43 / 60 30 90 100 100 40 Kellogg 48 39 48 44 51 45 / 70 40 100 100 100 70 Moses Lake 61 44 65 48 62 47 / 40 10 50 40 50 10 Wenatchee 60 46 63 51 60 47 / 0 10 40 30 50 0 Omak 56 41 58 44 58 43 / 50 10 70 50 70 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
334 PM CDT THU OCT 29 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 334 PM CDT THU OCT 29 2015 AT 3 PM...A TROUGH OF LOW PRESSURE WAS PRODUCING A NARROW BAND OF SHOWERS FROM EAU CLAIRE WISCONSIN TO DECORAH IOWA. THESE SHOWERS HAVE BEEN PRODUCING RAIN AMOUNTS UP TO A ONE HUNDREDTH OF AN INCH PER HOUR. WITH THE EXCEPTION OF THE HRRR WHICH KEPT SOME LINGERING SHOWERS CONTINUING ACROSS WESTERN WISCONSIN THROUGH 30.03Z...THE 29.12Z MODELS ARE IN GOOD AGREEMENT THAT THESE SHOWERS WILL MOVE EAST OF THE AREA BY THIS EVENING. WITH THE 925 MB AND 850 MB MOISTURE TRANSPORT DRAMATICALLY WEAKENING LATE THIS AFTERNOON AND SUBSIDENCE SHOWING UP IN THE SOUNDINGS OPTED TO KEEP THE FORECAST DRY. AHEAD OF THIS TROUGH...THERE IS A NARROW AREA OF CLEARING. THIS AREA IS CURRENTLY MOVING THROUGH THE LA CROSSE AREA. UPSTREAM OF THIS CLEARING THERE IS AN EXTENSIVE AREA OF LOW CLOUDS THAT EXTENDS NORTHWEST INTO THE CANADIAN PRAIRIES. SOUNDINGS SHOW THAT THESE CLOUDS WILL REMAIN TRAPPED BELOW THE SUBSIDENT INVERSION WHICH IS NEAR THE 875 MB. BASED ON THE SOUNDINGS IT LOOKS LIKE THESE CLOUDS WILL REMAIN THROUGH AT LEAST SATURDAY EVENING. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 334 PM CDT THU OCT 29 2015 FROM FRIDAY NIGHT THROUGH SATURDAY EVENING...THE 29.12Z MODELS CONTINUE TO SHOW THAT A LONG WAVE TROUGH WILL MOVE EAST THROUGH THE CENTRAL UNITED STATES. THIS INCLUDES THE MID AND UPPER MISSISSIPPI RIVER VALLEYS. WEAK 925 AND 850 MB MOISTURE TRANSPORT WILL MOVE INTO THE AREA LATE FRIDAY EVENING AND THEN CONTINUE INTO SATURDAY MORNING. THIS TRANSPORT THEN SHIFTS EAST OF THE AREA DURING THE AFTERNOON. PRECIPITABLE WATER VALUE SOUTH OF INTERSTATE 90 CLIMB INTO THE HALF TO ONE INCH RANGE...WHICH IS CLOSE TO CLIMATOLOGY FOR THIS TIME OF YEAR. AT THIS TIME...IT LOOKS LIKE RAINFALL TOTALS WILL BE UP TO A THIRD OF AN INCH. ON SUNDAY MORNING...A WARM FRONT WILL MOVE THROUGH THE REGION. BEHIND THIS FRONT...AN UNUSUALLY WARM AIR MASS WILL MOVE EAST INTO THE UPPER MISSISSIPPI RIVER VALLEY FROM THE HIGH PLAINS. 925 MB TEMPERATURES WILL RANGE FROM 13 TO 16C RANGE SUNDAY AND MONDAY...16 TO 19C ON TUESDAY...AND 15 TO 17C ON WEDNESDAY. THIS IS ANYWHERE FROM 1.5 TO 2 STANDARD DEVIATIONS ABOVE NORMAL. MIXING THESE TEMPERATURES DOWN TO THE SURFACE...RESULTS IN MID AND UPPER 60 TEMPERATURES ON SUNDAY AND MONDAY...AND LOWER TO POTENTIALLY MID 70S ON TUESDAY AND WEDNESDAY SOUTH OF INTERSTATE 94. HOWEVER TEMPERATURES NORTH OF I-94 MAY BE IMPACTED BY SOME MID AND HIGH CLOUDS FROM SUNDAY INTO MONDAY...SO KEPT THOSE TEMPERATURES CLOSER TO 60 DEGREES. THESE TEMPERATURES ARE ANYWHERE FROM 3 TO 5F WARMER THAN THE MODEL CONSENSUS. HOWEVER WITH ABUNDANT SUNSHINE... WOULD NOT BE TOO SURPRISED THAT SOME AREAS SOME OF INTERSTATE 94 COULD APPROACH RECORDS LEVELS FOR HIGH TEMPERATURES /IN THE MID 70S/ ON BOTH TUESDAY AND WEDNESDAY AFTERNOON AS GUSTY SOUTHWEST WINDS MIX DOWN THE VERY WARM AIR FROM ALOFT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1240 PM CDT THU OCT 29 2015 OVERCAST SKIES WILL CONTINUE AT KRST/KLSE THROUGH THE PERIOD. CEILINGS FROM 1000 TO 2000 FT AGL WILL BE THE RULE AT KRST AND FROM 1500 TO 2500 FT AGL AT KLSE. CURRENT CEILINGS OF 700 FT AGL AT KRST SHOULD RISE INTO THE LOWER MVFR RANGE LATER THIS AFTERNOON. WHETHER OR NOT CEILINGS ONCE AGAIN DROP BELOW 1000 FT AGL THIS EVENING AND OVERNIGHT IS LESS CERTAIN GIVEN LATEST SPREAD SHOWN BY FORECAST GUIDANCE AND WILL KEEP CEILINGS AROUND 1000 FT AGL FOR NOW. BRIEF PERIODS OF LIGHT DRIZZLE ARE POSSIBLE THROUGH THE AFTERNOON...BUT LIMITED COVERAGE PRECLUDES MENTION IN LATEST TAFS. SOME SLIGHT REDUCTIONS IN VISIBILITY POSSIBLE OVERNIGHT IN BR/HZ. BREEZY NORTHWEST WINDS THIS AFTERNOON WILL DECREASE THIS EVENING... BECOMING LIGHT AND VARIABLE AT KLSE. LIGHT WINDS WILL SHIFT TO THE SOUTH ON FRIDAY. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...ROGERS