Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/20/15


AREA FORECAST DISCUSSION
NWS NEW YORK NY
639 AM EST FRI DEC 18 2015 .SYNOPSIS... A WEAK WAVE OF LOW PRESSURE TRACKS NORTHEAST ALONG A FRONT LOCATED JUST EAST OF THE REGION TODAY. HIGH PRESSURE BUILDS IN FROM THE WEST THIS WEEKEND. HIGH PRESSURE PUSHES OFF THE EAST COAST SUNDAY NIGHT. A WARM FRONT LIFTS NORTH OF THE REGION MONDAY. A FRONTAL SYSTEM APPROACHES FROM THE WEST ON TUESDAY AND WEAKENS THROUGH WEDNESDAY. A COLD FRONT APPROACHES THURSDAY AND MOVES THROUGH THURSDAY NIGHT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MINOR CHANGES MADE TO REFLECT CURRENT CONDITIONS. WESTERLY FLOW IS SLOWLY ADVECTING LOWERING MIXING RATIOS INTO THE LOCAL REGION FROM THE WEST. TEMPS STILL 50-55 AS OF 3 AM. LOOKS LIKE MAXES OCCUR AT 7 AM. TEMPS THEN FALL SLIGHTLY OR BASICALLY HOLD STEADY THROUGH THE DAY. WATCHING THE SHORTWAVE AND SFC LOW NEAR NORFOLK ALONG THE FRONTAL BOUNDARY. CLOUD TOP COOLING NOTED OVER SOUTHEASTERN VA SUGGESTING CYCLOGENESIS HAS BEGUN. LATEST HRRR SPREADS LIGHT RAIN ACROSS LONG ISLAND AND EASTERN CT AROUND NOON. A FEW HUNDREDTHS AT MOST EXPECTED. INCLUDED SPRINKLES TO EMPHASIS THE LIGHT NATURE OF THE EXPECTED PCPN. POP`S IN LINE WITH NARRE-TL AT AROUND 30 PERCENT. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... FORECAST REMAINS ON TRACK FROM PREVIOUS. SHORTWAVE AXIS SWINGS TO THE COAST TONIGHT. WINDY AND COLD CONDITIONS EXPECTED BETWEEN DEEPENING CANADIAN MARITIMES LOW AND SOUTHERN US HIGH FRI NIGHT WITH WESTERLY WINDS INCREASING TO 15 TO 25 AND GUSTS 25 TO 35 MPH LATE. PERHAPS A FURRY AFTER MIDNIGHT WITH THE APPROACH OF THE UPPER SHORTWAVE. SURFACE HIGH PRES BUILDS IN FROM THE WEST ON SATURDAY. WITH LOW PRES OVER THE CANADIAN MARITIMES SLOW TO DEPART...THIS RESULTS IN A TIGHTENING PRESSURE GRADIENT OVER THE NORTHEAST. WEST TO NORTHWEST WINDS WILL RANGE FROM 15-20 MPH WITH 20-30 MPH GUSTS. TEMPERATURES WILL RETURN TO NORMAL WITH HIGHS IN THE UPPER 30S TO AROUND 40...AND THEN LOWS SATURDAY NIGHT WILL RANGE FROM THE LOWER30S IN/AROUND NYC TO THE LOWER 20S IN OUTLYING AREAS. THE WIND CHILL WILL START OFF IN THE TEEMS AND ONLY RISE TO THE UPPER 20S TO LOWER 30S DURING THE DAY. MEANWHILE...A DEEP UPPER TROUGH REMAINS ALONG THE EAST COAST...AND SEVERAL UPPER LEVEL SHORTWAVES WILL PASS THROUGH THE REGION ON SATURDAY. THERE MAY BE ENOUGH INSTABILITY TO SPARK OFF SOME FLURRIES ACROSS NORTHWEST ZONES SATURDAY AFTERNOON...BUT CONDS SHOULD GENERALLY BE DRY. MOSTLY 20S SATURDAY NIGHT...EXCEPT AROUND 30 IN NYC. SHOULD BE THE 1ST BELOW FREEZING TEMPERATURE OF THE SEASON IN CENTRAL PARK WITH A LOW OF 30 FORECAST. && .LONG TERM /SUNDAY THROUGH THURSDAY/... QUIET WEATHER FOR THE END OF THE WEEKEND INTO THE BEGINNING OF THE NEW WORK WEEK AS ZONAL FLOW ALOFT TRANSITIONS INTO RIDGING OVER THE NORTHEAST. SURFACE HIGH PRESSURE PUSHES OFF THE EAST COAST LATE SUNDAY. WARM AIR ADVECTION AS A WARM FRONT LIFTS NORTH OF THE REGION WILL ALLOW FOR WARMER TEMPERATURES SUNDAY NIGHT AND MORE NOTABLY ON MONDAY WHEN HIGH TEMPERATURES WARM MORE THAN 10 DEGREES IN SOME SPOTS FROM SUNDAY HIGH TEMPERATURES. ASSOCIATED COLD FRONT APPROACHES FROM THE WEST LATE MONDAY INTO TUESDAY AS LOW PRESSURE OVER THE GREAT LAKES HEADS NORTHEAST INTO SOUTHEASTERN CANADA. THIS WILL MARK THE BEGINNING OF AN UNSETTLED WEEK. THERE WILL BE A SLIGHT CHANCE FOR SHOWERS LATE MONDAY FOR WESTERN SECTIONS AND CHANCE EVERYWHERE BY LATE MONDAY NIGHT. THE COLD FRONT BECOMES STATIONARY AND WEAKENS BEFORE ENTERING OUR REGION INTO WEDNESDAY. CHANCE POPS CONTINUE WITH THE APPROACH OF THIS COLD FRONT. A STALLED FRONTAL BOUNDARY TO OUR NORTH WILL GIVE THE REGION BETTER LIFT AND THEREFORE A BETTER CHANCE FOR RAIN WEDNESDAY. ANOTHER COLD FRONT APPROACHES FROM THE WEST ON THURSDAY AND THIS FRONT WILL MAKE IT THROUGH THE REGION THURSDAY NIGHT...WITH HIGH PRESSURE BUILDING IN BEHIND IT FOR FRIDAY. THERE IS A GOOD DEAL OF UNCERTAINTY WITH THE MODELS IN REGARDS TO FRONTAL POSITIONS AND THEREFORE TIMING AND AMOUNTS OF RAINFALL. PERSISTENT SOUTHERLY FLOW LATE SUNDAY INTO THURSDAY WILL ALLOW FOR INCREASING HEIGHTS AND ABNORMALLY WARM AIR TO SETTLE OVER THE REGION MONDAY THROUGH FRIDAY. TEMPERATURES WARM INTO THE UPPER 40S AND MIDDLE 50S MONDAY...50S REGION-WIDE ON TUESDAY...AND CONTINUE TO WARM THROUGH THURSDAY...WITH MOST AREAS SEEING HIGHS AT OR JUST ABOVE 60. IF MODELS REMAIN CONSISTENT WITH THIS ABNORMALLY WARM AIR...RECORD HIGHS WILL LIKELY BE TIED OR BROKEN...MAINLY ON THURSDAY. A RECORD HIGH OR TWO MAY BE TIED OR BROKEN ON WEDNESDAY AS WELL. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... LOW PRESSURE WILL MOVE EAST OF LONG ISLAND THIS AFTERNOON. CONDITIONS HAVE IMPROVED TO VFR AT MOST OF THE TERMINALS...WITH SOME POCKETS OF MVFR AROUND. FOR NOW...AM THINKING THAT WE COULD BE IN AND OUT OF THE MVFR AND VFR TIL AROUND 13Z OR 14Z...THEN VFR FOR THE REMAINDER OF THE TAF PERIOD. THE ONLY QUESTION IS WHETHER OR NOT MVFR CIGS RETURN TO THE TERMINALS EAST OF NYC AS LOW PRESSURE PASSES NEARBY. A FEW SHOWERS WILL BE POSSIBLE AT KISP AND KGON. WINDS START OFF WNW LESS THAN 10 KT...THEN BECOME NW 10-15 KT AFT 13Z THRU THE DAY. OVERNIGHT...WINDS INCREASE A BIT MORE WITH GUSTS INTO THE 20 KT RANGE. 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: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR THIS MORNING. KLGA FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR THIS MORNING. KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR THIS MORNING. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR THIS MORNING. KHPN FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR THIS MORNING. KISP FCSTER COMMENTS: CHANCE OF MVFR CIGS LATE THIS MORNING AND EARLY AFTERNOON IN ANY SHOWERS. .OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY... .SATURDAY THROUGH SATURDAY NIGHT...VFR. WNW-W WINDS G25-35KT DURING THE DAY AND G20-25 KT AT NIGHT. .SUNDAY-SUNDAY NIGHT...VFR. W WINDS G15-20KT. .MONDAY...VFR. SW WINDS G15-25KT. SLIGHT CHANCE OF SHOWERS MON AFT/NIGHT. .TUESDAY...VFR...LIGHT WINDS. SLIGHT CHANCE OF SHOWERS. && .MARINE... COLD FRONT NOW OFF SHORE. SOUTHEASTERLY SWELLS ON THE OCEAN REPORTED WITH 4 TO 6 FT SEAS. SEAS BUILD PERHAPS ANOTHER FOOT DURING THE DAY. WINDS WILL PICK UP NOTICEABLY BY LATE IN THE DAY. FOR TONIGHT...SCA CONDITIONS ARE EXPECTED ON ALL WATERS WITH MINIMAL GALES DEVELOPING ON THE OCEAN WATERS WITH CAA AND A TIGHTENING PRESSURE GRADIENT. STRONG WNW FLOW CONTINUES THROUGH THE DAY ON SATURDAY. GALES FOR THE OCEAN AND SCA ELSEWHERE. THE PRESSURE GRADIENT RELAXES ON SUNDAY...AND CONDITIONS FALL BELOW SCA CRITERIA ON ALL WATERS. THEN A SW PRES GRADIENT TIGHTENS ON MONDAY BETWEEN HIGH PRES OVER THE WESTERN ATLANTIC AND A COLD FRONT MOVING INTO THE MIDWEST. THIS RESULTS IN SCA CONDS MONDAY AND MONDAY NIGHT. WINDS AND WAVES COME DOWN BELOW SCA ON TUESDAY. A PERSISTENT SOUTHERLY FLOW WILL ALLOW WAVES TO BUILD ABOVE 5 FT ON OCEAN WATERS ON WEDNESDAY. && .HYDROLOGY... THE NEXT RAINFALL IS FORECAST LATE TUESDAY INTO THURSDAY. THERE IS A GOOD AMOUNT OF UNCERTAINTY WITH HOW MUCH RAINFALL THE AREA WILL SEE IN THE LONG TERM. THIS COULD BE A PROLONGED EVENT WITH BASIN TOTALS OF UP TO 1.5 INCHES. NO HYDROLOGIC PROBLEMS ARE FORESEEN OTHER THAN POSSIBLE URBAN PONDING. && .HYDROLOGY... THE NEXT RAINFALL IS FORECAST LATE TUESDAY INTO THURSDAY. THERE IS A GOOD AMOUNT OF UNCERTAINTY WITH HOW MUCH RAINFALL THE AREA WILL SEE IN THE LONG TERM. THIS COULD BE A PROLONGED EVENT WITH BASIN TOTALS OF UP TO 1.5 INCHES. NO HYDROLOGIC PROBLEMS ARE FORESEEN OTHER THAN POSSIBLE URBAN PONDING. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO MIDNIGHT EST SATURDAY NIGHT FOR ANZ330-335-338-340-345. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ350-353- 355. GALE WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT EST SATURDAY NIGHT FOR ANZ350-353-355. && $$ SYNOPSIS...JP/TONGUE NEAR TERM...TONGUE SHORT TERM...TONGUE LONG TERM...JP AVIATION...BC MARINE...JP/TONGUE HYDROLOGY...JP/TONGUE
AREA FORECAST DISCUSSION
NWS NEW YORK NY
403 AM EST FRI DEC 18 2015 .SYNOPSIS... A WEAK WAVE OF LOW PRESSURE TRACKS NORTHEAST ALONG A FRONT LOCATED JUST EAST OF THE REGION TODAY. HIGH PRESSURE BUILDS IN FROM THE WEST THIS WEEKEND. HIGH PRESSURE PUSHES OFF THE EAST COAST SUNDAY NIGHT. A WARM FRONT LIFTS NORTH OF THE REGION MONDAY. A FRONTAL SYSTEM APPROACHES FROM THE WEST ON TUESDAY AND WEAKENS THROUGH WEDNESDAY. A COLD FRONT APPROACHES THURSDAY AND MOVES THROUGH THURSDAY NIGHT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WESTERLY FLOW IS SLOWLY ADVECTING LOWERING MIXING RATIOS INTO THE LOCAL REGION FROM THE WEST. TEMPS STILL 50-55 AS OF 3 AM. LOOKS LIKE MAXES OCCUR AT 7 AM. TEMPS THEN FALL SLIGHTLY OR BASICALLY HOLD STEADY THROUGH THE DAY. WATCHING THE SHORTWAVE AND SFC LOW NEAR NORFOLK ALONG THE FRONTAL BOUNDARY. CLOUD TOP COOLING NOTED OVER SOUTHEASTERN VA SUGGESTING CYCLOGENESIS HAS BEGUN. LATEST HRRR SPREADS LIGHT RAIN ACROSS LONG ISLAND AND EASTERN CT AROUND NOON. A FEW HUNDREDTHS AT MOST EXPECTED. INCLUDED SPRINKLES TO EMPHASIS THE LIGHT NATURE OF THE EXPECTED PCPN. POP`S IN LINE WITH NARRE-TL AT AROUND 30 PERCENT. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... FORECAST REMAINS ON TRACK FROM PREVIOUS. SHORTWAVE AXIS SWINGS TO THE COAST TONIGHT. WINDY AND COLD CONDITIONS EXPECTED BETWEEN DEEPENING CANADIAN MARITIMES LOW AND SOUTHERN US HIGH FRI NIGHT WITH WESTERLY WINDS INCREASING TO 15 TO 25 AND GUSTS 25 TO 35 MPH LATE. PERHAPS A FURRY AFTER MIDNIGHT WITH THE APPROACH OF THE UPPER SHORTWAVE. SURFACE HIGH PRES BUILDS IN FROM THE WEST ON SATURDAY. WITH LOW PRES OVER THE CANADIAN MARITIMES SLOW TO DEPART...THIS RESULTS IN A TIGHTENING PRESSURE GRADIENT OVER THE NORTHEAST. WEST TO NORTHWEST WINDS WILL RANGE FROM 15-20 MPH WITH 20-30 MPH GUSTS. TEMPERATURES WILL RETURN TO NORMAL WITH HIGHS IN THE UPPER 30S TO AROUND 40...AND THEN LOWS SATURDAY NIGHT WILL RANGE FROM THE LOWER30S IN/AROUND NYC TO THE LOWER 20S IN OUTLYING AREAS. THE WIND CHILL WILL START OFF IN THE TEEMS AND ONLY RISE TO THE UPPER 20S TO LOWER 30S DURING THE DAY. MEANWHILE...A DEEP UPPER TROUGH REMAINS ALONG THE EAST COAST...AND SEVERAL UPPER LEVEL SHORTWAVES WILL PASS THROUGH THE REGION ON SATURDAY. THERE MAY BE ENOUGH INSTABILITY TO SPARK OFF SOME FLURRIES ACROSS NORTHWEST ZONES SATURDAY AFTERNOON...BUT CONDS SHOULD GENERALLY BE DRY. MOSTLY 20S SATURDAY NIGHT...EXCEPT AROUND 30 IN NYC. SHOULD BE THE 1ST BELOW FREEZING TEMPERATURE OF THE SEASON IN CENTRAL PARK WITH A LOW OF 30 FORECAST. && .LONG TERM /SUNDAY THROUGH THURSDAY/... QUIET WEATHER FOR THE END OF THE WEEKEND INTO THE BEGINNING OF THE NEW WORK WEEK AS ZONAL FLOW ALOFT TRANSITIONS INTO RIDGING OVER THE NORTHEAST. SURFACE HIGH PRESSURE PUSHES OFF THE EAST COAST LATE SUNDAY. WARM AIR ADVECTION AS A WARM FRONT LIFTS NORTH OF THE REGION WILL ALLOW FOR WARMER TEMPERATURES SUNDAY NIGHT AND MORE NOTABLY ON MONDAY WHEN HIGH TEMPERATURES WARM MORE THAN 10 DEGREES IN SOME SPOTS FROM SUNDAY HIGH TEMPERATURES. ASSOCIATED COLD FRONT APPROACHES FROM THE WEST LATE MONDAY INTO TUESDAY AS LOW PRESSURE OVER THE GREAT LAKES HEADS NORTHEAST INTO SOUTHEASTERN CANADA. THIS WILL MARK THE BEGINNING OF AN UNSETTLED WEEK. THERE WILL BE A SLIGHT CHANCE FOR SHOWERS LATE MONDAY FOR WESTERN SECTIONS AND CHANCE EVERYWHERE BY LATE MONDAY NIGHT. THE COLD FRONT BECOMES STATIONARY AND WEAKENS BEFORE ENTERING OUR REGION INTO WEDNESDAY. CHANCE POPS CONTINUE WITH THE APPROACH OF THIS COLD FRONT. A STALLED FRONTAL BOUNDARY TO OUR NORTH WILL GIVE THE REGION BETTER LIFT AND THEREFORE A BETTER CHANCE FOR RAIN WEDNESDAY. ANOTHER COLD FRONT APPROACHES FROM THE WEST ON THURSDAY AND THIS FRONT WILL MAKE IT THROUGH THE REGION THURSDAY NIGHT...WITH HIGH PRESSURE BUILDING IN BEHIND IT FOR FRIDAY. THERE IS A GOOD DEAL OF UNCERTAINTY WITH THE MODELS IN REGARDS TO FRONTAL POSITIONS AND THEREFORE TIMING AND AMOUNTS OF RAINFALL. PERSISTENT SOUTHERLY FLOW LATE SUNDAY INTO THURSDAY WILL ALLOW FOR INCREASING HEIGHTS AND ABNORMALLY WARM AIR TO SETTLE OVER THE REGION MONDAY THROUGH FRIDAY. TEMPERATURES WARM INTO THE UPPER 40S AND MIDDLE 50S MONDAY...50S REGION-WIDE ON TUESDAY...AND CONTINUE TO WARM THROUGH THURSDAY...WITH MOST AREAS SEEING HIGHS AT OR JUST ABOVE 60. IF MODELS REMAIN CONSISTENT WITH THIS ABNORMALLY WARM AIR...RECORD HIGHS WILL LIKELY BE TIED OR BROKEN...MAINLY ON THURSDAY. A RECORD HIGH OR TWO MAY BE TIED OR BROKEN ON WEDNESDAY AS WELL. && .AVIATION /09Z FRIDAY THROUGH TUESDAY/... LOW PRESSURE WILL MOVE EAST OF LONG ISLAND THIS AFTERNOON. CONDITIONS HAVE IMPROVED TO MVFR OR VFR AT MOST TERMINALS...WITH THE EXCEPTION OF KGON...WHERE IT WILL TAKE A LITTLE BIT LONGER FOR IMPROVEMENT TO TAKE PLACE. FOR NOW...AM THINKING THAT WE COULD BE IN AND OUT OF MVFR AND VFR TIL AROUND 13Z OR 14Z...THEN VFR FOR THE REMAINDER OF THE TAF PERIOD. THE ONLY QUESTION IS WHETHER OR NOT MVFR CIGS RETURN TO THE TERMINALS EAST OF NYC AS LOW PRESSURE PASSES NEARBY. A FEW SHOWERS WILL BE POSSIBLE AT KISP AND KGON. WINDS WILL BE WNW LESS THAN 10 KT TONIGHT...THEN NW 10-15 KT AFT 13Z THRU THE DAY. 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: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. KLGA FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. KHPN FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. KISP FCSTER COMMENTS: CHANCE OF MVFR CIGS LATE THIS MORNING AND EARLY AFTERNOON IN ANY SHOWERS. .OUTLOOK FOR 06Z SATURDAY THROUGH TUESDAY... .FRIDAY NIGHT...MAINLY VFR. WNW WINDS G20-25KT. .SATURDAY THROUGH SATURDAY NIGHT...VFR. WNW-W WINDS G25-35KT DURING THE DAY AND G20-25 KT AT NIGHT. .SUNDAY-SUNDAY NIGHT...VFR. W WINDS G15-20KT. .MONDAY...VFR. SW WINDS G15-25KT. SLIGHT CHANCE OF SHOWERS MON AFT/NIGHT. .TUESDAY...VFR...LIGHT WINDS. SLIGHT CHANCE OF SHOWERS. && .MARINE... COLD FRONT NOW OFF SHORE. SOUTHEASTERLY SWELLS ON THE OCEAN REPORTED WITH 4 TO 6 FT SEAS. SEAS BUILD PERHAPS ANOTHER FOOT DURING THE DAY. WINDS WILL PICK UP NOTICEABLY BY LATE IN THE DAY. FOR TONIGHT...SCA CONDITIONS ARE EXPECTED ON ALL WATERS WITH MINIMAL GALES DEVELOPING ON THE OCEAN WATERS WITH CAA AND A TIGHTENING PRESSURE GRADIENT. STRONG WNW FLOW CONTINUES THROUGH THE DAY ON SATURDAY. GALES FOR THE OCEAN AND SCA ELSEWHERE. THE PRESSURE GRADIENT RELAXES ON SUNDAY...AND CONDITIONS FALL BELOW SCA CRITERIA ON ALL WATERS. THEN A SW PRES GRADIENT TIGHTENS ON MONDAY BETWEEN HIGH PRES OVER THE WESTERN ATLANTIC AND A COLD FRONT MOVING INTO THE MIDWEST. THIS RESULTS IN SCA CONDS MONDAY AND MONDAY NIGHT. WINDS AND WAVES COME DOWN BELOW SCA ON TUESDAY. A PERSISTENT SOUTHERLY FLOW WILL ALLOW WAVES TO BUILD ABOVE 5 FT ON OCEAN WATERS ON WEDNESDAY. && .HYDROLOGY... THE NEXT RAINFALL IS FORECAST LATE TUESDAY INTO THURSDAY. THERE IS A GOOD AMOUNT OF UNCERTAINTY WITH HOW MUCH RAINFALL THE AREA WILL SEE IN THE LONG TERM. THIS COULD BE A PROLONGED EVENT WITH BASIN TOTALS OF UP TO 1.5 INCHES. NO HYDROLOGIC PROBLEMS ARE FORESEEN OTHER THAN POSSIBLE URBAN PONDING. && .HYDROLOGY... THE NEXT RAINFALL IS FORECAST LATE TUESDAY INTO THURSDAY. THERE IS A GOOD AMOUNT OF UNCERTAINTY WITH HOW MUCH RAINFALL THE AREA WILL SEE IN THE LONG TERM. THIS COULD BE A PROLONGED EVENT WITH BASIN TOTALS OF UP TO 1.5 INCHES. NO HYDROLOGIC PROBLEMS ARE FORESEEN OTHER THAN POSSIBLE URBAN PONDING. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO MIDNIGHT EST SATURDAY NIGHT FOR ANZ330-335-338-340-345. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ350-353- 355. GALE WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT EST SATURDAY NIGHT FOR ANZ350-353-355. && $$ SYNOPSIS...JP/TONGUE NEAR TERM...TONGUE SHORT TERM...TONGUE LONG TERM...JP AVIATION...BC MARINE...JP/TONGUE HYDROLOGY...JP/TONGUE
AREA FORECAST DISCUSSION
NWS NEW YORK NY
344 AM EST FRI DEC 18 2015 .SYNOPSIS... A WEAK WAVE OF LOW PRESSURE TRACKS NORTHEAST ALONG A FRONT LOCATE JUST EAST OF THE REGION TODAY. HIGH PRESSURE BUILDS IN FROM THE WEST THIS WEEKEND. HIGH PRESSURE PUSHES OFF THE EAST COAST SUNDAY NIGHT. A WARM FRONT LIFTS NORTH OF THE REGION MONDAY. A FRONTAL SYSTEM APPROACHES FROM THE WEST ON TUESDAY AND WEAKENS THROUGH WEDNESDAY. A COLD FRONT APPROACHES THURSDAY AND MOVES THROUGH THURSDAY NIGHT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WESTERLY FLOW IS SLOWLY ADVECTING LOWERING MIXING RATIOS INTO THE LOCAL REGION FROM THE WEST. TEMPS STILL 50-55 AS OF 3 AM. LOOKS LIKE MAXES OCCUR AT 7 AM. TEMPS THEN FALL SLIGHTLY OR BASICALLY HOLD STEADY THROUGH THE DAY. WATCHING THE SHORTWAVE AND SFC LOW NEAR NORFOLK ALONG THE FRONTAL BOUNDARY. CLOUD TOP COOLING NOTED OVER SOUTHEASTERN VA SUGGESTING CYCLOGENESIS HAS BEGUN. LATEST HRRR SPREADS LIGHT RAIN ACROSS LONG ISLAND AND EASTERN CT AROUND NOON. A FEW HUNDREDTHS AT MOST EXPECTED. INCLUDED SPRINKLES TO EMPHASIS THE LIGHT NATURE OF THE EXPECTED PCPN. POP`S IN LINE WITH NARRE-TL AT AROUND 30 PERCENT. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... FORECAST REMAINS ON TRACK FROM PREVIOUS. SHORTWAVE AXIS SWINGS TO THE COAST TONIGHT. WINDY AND COLD CONDITIONS EXPECTED BETWEEN DEEPENING CANADIAN MARITIMES LOW AND SOUTHERN US HIGH FRI NIGHT WITH WESTERLY WINDS INCREASING TO 15 TO 25 AND GUSTS 25 TO 35 MPH LATE. PERHAPS A FURRY AFTER MIDNIGHT WITH THE APPROACH OF THE UPPER SHORTWAVE. SURFACE HIGH PRES BUILDS IN FROM THE WEST ON SATURDAY. WITH LOW PRES OVER THE CANADIAN MARITIMES SLOW TO DEPART...THIS RESULTS IN A TIGHTENING PRESSURE GRADIENT OVER THE NORTHEAST. WEST TO NORTHWEST WINDS WILL RANGE FROM 15-20 MPH WITH 20-30 MPH GUSTS. TEMPERATURES WILL RETURN TO NORMAL WITH HIGHS IN THE UPPER 30S TO AROUND 40...AND THEN LOWS SATURDAY NIGHT WILL RANGE FROM THE LOWER30S IN/AROUND NYC TO THE LOWER 20S IN OUTLYING AREAS. THE WIND CHILL WILL START OFF IN THE TEEMS AND ONLY RISE TO THE UPPER 20S TO LOWER 30S DURING THE DAY. MEANWHILE...A DEEP UPPER TROUGH REMAINS ALONG THE EAST COAST...AND SEVERAL UPPER LEVEL SHORTWAVES WILL PASS THROUGH THE REGION ON SATURDAY. THERE MAY BE ENOUGH INSTABILITY TO SPARK OFF SOME FLURRIES ACROSS NORTHWEST ZONES SATURDAY AFTERNOON...BUT CONDS SHOULD GENERALLY BE DRY. MOSTLY 20S SATURDAY NIGHT...EXCEPT AROUND 30 IN NYC. SHOULD BE THE 1ST BELOW FREEZING TEMPERATURE OF THE SEASON IN CENTRAL PARK WITH A LOW OF 30 FORECAST. && .LONG TERM /SUNDAY THROUGH THURSDAY/... QUIET WEATHER FOR THE END OF THE WEEKEND INTO THE BEGINNING OF THE NEW WORK WEEK AS ZONAL FLOW ALOFT TRANSITIONS INTO RIDGING OVER THE NORTHEAST. SURFACE HIGH PRESSURE PUSHES OFF THE EAST COAST LATE SUNDAY. WARM AIR ADVECTION AS A WARM FRONT LIFTS NORTH OF THE REGION WILL ALLOW FOR WARMER TEMPERATURES SUNDAY NIGHT AND MORE NOTABLY ON MONDAY WHEN HIGH TEMPERATURES WARM MORE THAN 10 DEGREES IN SOME SPOTS FROM SUNDAY HIGH TEMPERATURES. ASSOCIATED COLD FRONT APPROACHES FROM THE WEST LATE MONDAY INTO TUESDAY AS LOW PRESSURE OVER THE GREAT LAKES HEADS NORTHEAST INTO SOUTHEASTERN CANADA. THIS WILL MARK THE BEGINNING OF AN UNSETTLED WEEK. THERE WILL BE A SLIGHT CHANCE FOR SHOWERS LATE MONDAY FOR WESTERN SECTIONS AND CHANCE EVERYWHERE BY LATE MONDAY NIGHT. THE COLD FRONT BECOMES STATIONARY AND WEAKENS BEFORE ENTERING OUR REGION INTO WEDNESDAY. CHANCE POPS CONTINUE WITH THE APPROACH OF THIS COLD FRONT. A STALLED FRONTAL BOUNDARY TO OUR NORTH WILL GIVE THE REGION BETTER LIFT AND THEREFORE A BETTER CHANCE FOR RAIN WEDNESDAY. ANOTHER COLD FRONT APPROACHES FROM THE WEST ON THURSDAY AND THIS FRONT WILL MAKE IT THROUGH THE REGION THURSDAY NIGHT...WITH HIGH PRESSURE BUILDING IN BEHIND IT FOR FRIDAY. THERE IS A GOOD DEAL OF UNCERTAINTY WITH THE MODELS IN REGARDS TO FRONTAL POSITIONS AND THEREFORE TIMING AND AMOUNTS OF RAINFALL. PERSISTENT SOUTHERLY FLOW LATE SUNDAY INTO THURSDAY WILL ALLOW FOR INCREASING HEIGHTS AND ABNORMALLY WARM AIR TO SETTLE OVER THE REGION MONDAY THROUGH FRIDAY. TEMPERATURES WARM INTO THE UPPER 40S AND MIDDLE 50S MONDAY...50S REGION-WIDE ON TUESDAY...AND CONTINUE TO WARM THROUGH THURSDAY...WITH MOST AREAS SEEING HIGHS AT OR JUST ABOVE 60. IF MODELS REMAIN CONSISTENT WITH THIS ABNORMALLY WARM AIR...RECORD HIGHS WILL LIKELY BE TIED OR BROKEN...MAINLY ON THURSDAY. A RECORD HIGH OR TWO MAY BE TIED OR BROKEN ON WEDNESDAY AS WELL. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... LOW PRESSURE WILL MOVE EAST OF LONG ISLAND THIS AFTERNOON. CONDITIONS HAVE IMPROVED TO MVFR OR VFR AT MOST TERMINALS...WITH THE EXCEPTION OF KGON...WHERE IT WILL TAKE A LITTLE BIT LONGER FOR IMPROVEMENT TO TAKE PLACE. FOR NOW...AM THINKING THAT WE COULD BE IN AND OUT OF MVFR AND VFR TIL AROUND 13Z OR 14Z...THEN VFR FOR THE REMAINDER OF THE TAF PERIOD. THE ONLY QUESTION IS WHETHER OR NOT MVFR CIGS RETURN TO THE TERMINALS EAST OF NYC AS LOW PRESSURE PASSES NEARBY. A FEW SHOWERS WILL BE POSSIBLE AT KISP AND KGON. WINDS WILL BE WNW LESS THAN 10 KT TONIGHT...THEN NW 10-15 KT AFT 13Z THRU THE DAY. ...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: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. KLGA FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. KHPN FCSTER COMMENTS: AMENDMENTS POSSIBLE AS FLIGHT CATEGORIES VARY BETWEEN MVFR AND VFR. KISP FCSTER COMMENTS: CHANCE OF MVFR CIGS LATE THIS MORNING AND EARLY AFTERNOON IN ANY SHOWERS. .OUTLOOK FOR 06Z SATURDAY THROUGH TUESDAY... .FRIDAY NIGHT...MAINLY VFR. WNW WINDS G20-25KT. .SATURDAY THROUGH SATURDAY NIGHT...VFR. WNW-W WINDS G25-35KT DURING THE DAY AND G20-25 KT AT NIGHT. .SUNDAY-SUNDAY NIGHT...VFR. W WINDS G15-20KT. .MONDAY...VFR. SW WINDS G15-25KT. SLIGHT CHANCE OF SHOWERS MON AFT/NIGHT. .TUESDAY...VFR...LIGHT WINDS. SLIGHT CHANCE OF SHOWERS. && .MARINE... COLD FRONT NOW OFF SHORE. SOUTHEASTERLY SWELLS ON THE OCEAN REPORTED WITH 4 TO 6 FT SEAS. SEAS BUILD PERHAPS ANOTHER FOOT DURING THE DAY. WINDS WILL PICK UP NOTICEABLY BY LATE IN THE DAY. FOR TONIGHT...SCA CONDITIONS ARE EXPECTED ON ALL WATERS WITH MINIMAL GALES DEVELOPING ON THE OCEAN WATERS WITH CAA AND A TIGHTENING PRESSURE GRADIENT. STRONG WNW FLOW CONTINUES THROUGH THE DAY ON SATURDAY. GALES FOR THE OCEAN AND SCA ELSEWHERE. THE PRESSURE GRADIENT RELAXES ON SUNDAY...AND CONDITIONS FALL BELOW SCA CRITERIA ON ALL WATERS. THEN A SW PRES GRADIENT TIGHTENS ON MONDAY BETWEEN HIGH PRES OVER THE WESTERN ATLANTIC AND A COLD FRONT MOVING INTO THE MIDWEST. THIS RESULTS IN SCA CONDS MONDAY AND MONDAY NIGHT. WINDS AND WAVES COME DOWN BELOW SCA ON TUESDAY. A PERSISTENT SOUTHERLY FLOW WILL ALLOW WAVES TO BUILD ABOVE 5 FT ON OCEAN WATERS ON WEDNESDAY. && .HYDROLOGY... THE NEXT RAINFALL IS FORECAST LATE TUESDAY INTO THURSDAY. THERE IS A GOOD AMOUNT OF UNCERTAINTY WITH HOW MUCH RAINFALL THE AREA WILL SEE IN THE LONG TERM. THIS COULD BE A PROLONGED EVENT WITH BASIN TOTALS OF UP TO 1.5 INCHES. NO HYDROLOGIC PROBLEMS ARE FORESEEN OTHER THAN POSSIBLE URBAN PONDING. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...GALE WATCH FROM LATE TONIGHT THROUGH LATE SATURDAY NIGHT FOR ANZ350-353-355. SMALL CRAFT ADVISORY UNTIL 1 AM EST SATURDAY FOR ANZ350-353- 355. && $$ SYNOPSIS...JP/TONGUE NEAR TERM...TONGUE SHORT TERM...TONGUE LONG TERM...JP AVIATION...BC MARINE...JP/TONGUE HYDROLOGY...JP/TONGUE
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
324 PM EST FRI DEC 18 2015 .SYNOPSIS... NORTHWEST FLOW WILL REMAIN ACROSS THE AREA INTO SATURDAY, WITH A WEAK SURFACE TROUGH CROSSING THE AREA DURING THE DAY. HIGH PRESSURE BUILDS ACROSS THE MID ATLANTIC SUNDAY, THEN BUILDS OFFSHORE SUNDAY NIGHT AS A WARM FRONT LIFTS NORTH OF THE AREA. A COLD FRONT WILL APPROACH THE AREA EARLY NEXT WEEK, BUT MAY STALL TO OUR WEST AND NORTH. MEANWHILE, A WEAK COASTAL FRONT MAY AFFECT THE AREA TUESDAY NIGHT INTO WEDNESDAY. ANOTHER COLD FRONT APPROACHES FROM THE WEST ON THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... A COLD FRONTAL BOUNDARY WHICH MOVED THROUGH EARLY THIS MORNING WILL CONTINUE TO MOVE OFFSHORE. STUBBORN CLOUDS WHICH HAVE BEEN IN PLACE THROUGHOUT MOST OF THE DAY WILL SLOWLY SCATTER OUT OVERNIGHT OUTSIDE OF THE POCONOS. WEST TO NORTHWEST WINDS WILL CONTINUE TO BE GUSTY AT TIMES, CLOSE TO 20 MPH. NOT MUCH CAUSE TO DEVIATE FROM MET/MAV GUIDANCE ON MOST FORECAST ELEMENTS IN THIS PERIOD. WITH THAT SAID, LOWS SHOULD DROP TO THE MID 20`S TO LOW 30`S FOR MOST. A GOOD SHOT AT A FREEZING OR LOWER LOW TEMPERATURE AT PHILADELPHIA INTERNATIONAL AIRPORT TONIGHT. TRY SAYING THAT FIVE TIMES FAST. THE WESTERLY- NORTHWESTERLY WINDS WILL ACTUALLY BRING A MOISTURE STREAM OFF THE GREAT LAKES INTO THE POCONOS OVERNIGHT. THE HIRES NAM HAS SOME SCATTERED SNOW SHOWERS MOVING INTO THE REGION ACROSS THE POCONOS OVERNIGHT AIDED BY THE HIGH TERRAIN. GETTING FULLY INTO THE RANGE OF THE RAP AND HRRR MESOSCALE MODELS MAY HELP PIN THE SNOW SHOWERS A BIT MORE THAN WHAT WE HAVE NOW, THIS SHOULD OCCUR LATER THIS EVENING. WITH TEMPERATURES FALLING INTO THE LOW 20`S FOR THE POCONOS, SOME SLICK SPOTS MAY FORM. SO EXERCISE CAUTION IF TRAVELING IN THE POCONOS TOWARD SUNRISE, WILL FEATURE THIS IN THE HWO AS WELL. && .SHORT TERM /SATURDAY/... STRONG WINDS WILL CONTINUE TO BE THE MAIN STORY ON SATURDAY AS WELL. MODEL SOUNDINGS SUGGEST THE POTENTIAL FOR SUSTAINED WINDS NEAR 20 MPH WITH GUSTS AROUND OR EVEN A BIT HIGHER THAN 30 MPH. MODELING WAS TO HIGH WITH TOP THE GUSTS TODAY. HOWEVER, SATURDAY WILL BE THE MAIN PUSH OF CAA WITH A SECONDARY TROUGH MOVING THROUGH THE REGION. STEEP LOW LEVEL LAPSE RATES WILL ALSO BE PRESENT ACROSS THE REGION AS WELL. THIS WILL LEAD TO A REDEVELOPMENT OF SCATTERED AFTERNOON CUMULUS OUTSIDE OF THE REGIONS DISCUSSED BELOW. GIVEN THE STRONG CAA AND SCATTERED CUMULUS, DID GO A COUPLE OF DEGREES COOLER THAN THE MET/MAV GUIDANCE AND AWAY FROM THE OUTLIER WARM ECMWF MOS. IN TERMS OF THE PROSPECTS FOR SCATTERED SNOW SHOWERS, MODELING CONTINUES TO SHOW NORTHWEST NJ, THE POCONOS AND THE LEHIGH VALLEY AS STANDING THE BEST CHANCE TO SEE SNOW. THE SCATTERED SNOW SHOWERS WILL BE CAUSED BY MOISTURE MOVING INTO THIS REGION FROM THE GREAT LAKES WITH THE WEST TO NORTHWEST WINDS. ALSO, THE STEEP LAPSE RATES WILL ADD AN ELEMENT OF INSTABILITY TO THE SET-UP WHICH COULD LOCALLY ENHANCE A SNOW SHOWER OR TWO. OVERALL, ANY SNOW ACCUMULATION IS EXPECTED TO BE UNDER AN INCH IN MOST SPOTS ATTM. SOME SLICK SPOTS WILL BE POSSIBLE WITH THE SNOW SHOWER ACTIVITY AS WELL. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... A COOL, CLOSER TO NORMAL, AND MOSTLY DRY START TO THE LONG TERM FORECAST SUNDAY, FOLLOWED BY WARMING CONDITIONS AND POSSIBLE UNSETTLED WEATHER FOR NEXT WEEK. FOR SATURDAY NIGHT AND SUNDAY, HIGH PRESSURE WILL BE BUILDING ACROSS THE MID ATLANTIC FROM THE SOUTH, BEFORE BUILDING OFFSHORE SUNDAY NIGHT. THIS WILL PROVIDE DRY WEATHER THROUGH SUNDAY NIGHT. SATURDAY NIGHT/SUNDAY MORNING IS EXPECTED TO BE THE COLDEST NIGHT OF THE LONG TERM PERIOD. A WARM FRONT IS EXPECTED TO LIFT NORTH OF THE AREA ON MONDAY, WHILE A COLD FRONT APPROACHES FROM THE WEST. THIS FRONT IS CURRENTLY EXPECTED TO STALL OUT TO OUR NORTH AND WEST TUESDAY AND NOT MAKE IT INTO OUR AREA AS IT WILL BEGIN LIFTING BACK NORTHWARD THROUGH WEDNESDAY. MEANWHILE, AN INVERTED TROUGH/FRONTAL BOUNDARY MAY DEVELOP TO OUR SOUTH TUESDAY NIGHT AND LIFT NORTH ACROSS OUR AREA THROUGH WEDNESDAY NIGHT. SEVERAL SHORT WAVE/VORTICITY IMPULSES ARE FORECAST TO MOVE ACROSS THE AREA MONDAY THROUGH WEDNESDAY, ESPECIALLY AS THE INVERTED TROUGH/FRONT LIFTS ACROSS THE AREA. THERE IS A CHANCE OF SHOWERS EACH DAY, WITH THE HIGHEST PROBABILITY TUESDAY NIGHT INTO WEDNESDAY AS THE STRONGEST VORTICITY AND THE TROUGH LIFT ACROSS THE AREA. MONDAY COULD BE A GUSTY DAY WITH GUSTS UP TO 25-35 MPH POSSIBLE IF STRONG ENOUGH MIXING OCCURS DURING THE DAYTIME HOURS. AS WE MOVE THROUGH THURSDAY INTO THURSDAY NIGHT, A COLD FRONT IS EXPECTED TO MOVE ACROSS THE AREA. MODEL GUIDANCE MOSTLY DRIES OUT THE PRECIPITATION BEFORE REACHING OUR AREA, HOWEVER, THERE STILL REMAINS A CHANCE OF SHOWERS. AFTER SUNDAY, TEMPERATURES WILL CONTINUE TO RISE AND BE VERY WARM ACROSS THE AREA, REACHING 20-25 DEGREES ABOVE NORMAL FOR WEDNESDAY INTO THURSDAY. ONCE AGAIN, TEMPERATURES COULD APPROACH RECORDS WEDNESDAY AND RECORDS COULD BE BROKEN THURSDAY OF NEXT WEEK. TEMPERATURES ARE EXPECTED TO DROP BY FRIDAY BEHIND THE FRONTAL BOUNDARY, BUT ARE STILL EXPECTED TO BE WELL ABOVE NORMAL. FRIDAY COULD BE ANOTHER GUSTY DAY AS LOW PRESSURE WILL BE LOCATED WELL TO OUR NORTH, AND HIGH PRESSURE BUILDS IN FROM THE SOUTHWEST. && .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. REST OF THIS AFTERNOON... CEILINGS SHOULD GRADUALLY RISE TO AROUND 5,000 FEET FOR THE REST OF THIS AFTERNOON WITH A FEW BREAKS IN THE DECK. NORTHWEST WIND GUSTS LOOK TO BE AROUND 20 KNOTS AT TIMES. TONIGHT... CLOUDS WILL BECOME MORE SCATTERED AT TIMES TONIGHT, STILL VFR. MAIN STORY WILL CONTINUE TO BE WEST TO NORTHWEST WIND GUSTS AROUND 20 KNOTS AT TIMES FOR ALL TAF SITES. SATURDAY...VFR. WEST-NORTHWEST 15-20 KNOTS WITH GUSTS TO 30 KNOTS, HIGHEST IN THE AFTERNOON AT ALL TAF SITES. SOME ISOLATED SNOW SHOWERS POSSIBLE FOR KABE, GIVEN LOW CHANCE HAVE LEFT OUT OFF TAF ATTM. OUTLOOK... SATURDAY NIGHT-SUNDAY NIGHT...VFR CONDITIONS EXPECTED. WEST TO NORTHWEST WINDS SATURDAY NIGHT AND SUNDAY, BECOMING SOUTHWEST LATE SUNDAY INTO SUNDAY NIGHT. MONDAY-MONDAY NIGHT...VFR EARLY MONDAY. CONDITIONS POSSIBLY LOWERING TO MVFR LATER MONDAY INTO MONDAY NIGHT WITH A CHANCE OF SHOWERS. SOUTHWEST WINDS 10-15 KNOTS, POSSIBLY BECOMING GUSTY DURING THE DAY MONDAY. TUESDAY-WEDNESDAY...A CHANCE OF SHOWERS AND LOWER CONDITIONS POSSIBLE TUESDAY INTO WEDNESDAY. && .MARINE... SEAS HAVE REMAINED AROUND FIVE FEET THROUGHOUT MOST OF THE DAY ON THE OCEAN AND A BIT LOWER IN THE BAY. WAVE HEIGHTS WILL CONTINUE TO BE NEAR FIVE FEET THROUGH SATURDAY AFTERNOON ON THE OCEAN. HOWEVER, WIND GUSTS NOW OCCASIONALLY NEAR 20 KNOTS WILL CONTINUE TO SLOWLY RAMP-UP TONIGHT. WIND GUSTS ARE LIKELY TO REACH 35 KNOTS AFTER MIDNIGHT AND REMAIN NEAR 35 KNOTS AT TIMES THROUGH SATURDAY. THE GALE WARNING REMAINS UNCHANGED STARTING AT MIDNIGHT AND GOING THROUGH THE DAY ON SATURDAY. OUTLOOK... SATURDAY NIGHT...CONDITIONS EXPECTED TO SUBSIDE TO SMALL CRAFT ADVISORY LEVELS OVERNIGHT. SUNDAY-SUNDAY NIGHT...CONDITIONS SUBSIDE TO SUB-SMALL CRAFT ADVISORY LEVELS AND CONTINUE THROUGH SUNDAY NIGHT.. MONDAY-MONDAY NIGHT...SMALL CRAFT ADVISORY CONDITIONS LIKELY. TUESDAY-WEDNESDAY...SUB-SMALL CRAFT ADVISORY CONDITIONS EXPECTED. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...GALE WARNING FROM MIDNIGHT TONIGHT TO 10 PM EST SATURDAY FOR ANZ450>455. GALE WARNING FROM MIDNIGHT TONIGHT TO 7 PM EST SATURDAY FOR ANZ430-431. && $$ SYNOPSIS...ROBERTSON NEAR TERM...GAINES SHORT TERM...GAINES LONG TERM...ROBERTSON AVIATION...GAINES/ROBERTSON MARINE...GAINES/ROBERTSON
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
654 AM EST FRI DEC 18 2015 .SYNOPSIS... LOW PRESSURE TRACKS OFFSHORE TODAY, MEANWHILE A STRENGTHENING AREA OF HIGH PRESSURE WILL BUILD TO OUR SOUTH AND WEST LATER TODAY THROUGH SATURDAY. THIS HIGH THEN BRIEFLY SETTLES OVER OUR REGION SUNDAY BEFORE MOVING OFFSHORE. A WEAK COLD FRONT WILL APPROACH TUESDAY INTO WEDNESDAY, HOWEVER IT SHOULD DISSIPATE THEN A STRONGER COLD FRONT APPROACHES LATE THURSDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MAX TEMPERATURES FOR THE CALENDAR DAY FRIDAY ALREADY OCCURRED EARLIER THIS MORNING, AROUND MIDNIGHT...50S...OR GENERALLY NEAR 10 DEGREES ABOVE NORMAL FOR THE 18TH. TODAY...MOSTLY CLOUDY THROUGH MIDDAY AS THE TROUGH ALOFT APPROACHES WITH ITS LAST OPEN WAVE OF LOW PRESSURE EAST OF NEW JERSEY BY LATE MORNING. LATEST HRRR BACKED OFF IN CENTRAL NNJ AND SO MY POPS MAY BE OVERDONE MORE THAN 15 MI INLAND. NO MATTER...THE PRIMARY AREA FOR SHOWERS THIS MORNING IS THE SE CORNER OF SUSSEX COUNTY DE INTO CAPE MAY NJ AS WELL AS THE COASTAL SLIVER OF ATLC COUNTY. POPS PER 00Z/18 UKMET/00Z AND 06Z NAM/AND THE 08Z HRRR. THEN PARTIAL CLEARING FROM WEST TO EAST LATE THIS MORNING AND DURING THE AFTERNOON AS NORTHWEST WINDS BECOME GUSTY 20-25 MPH. GUSTINESS THIS MORNING APPEARS BRIEF AND ASSTD WITH DRY AIR ADVECTION. TEMPERATURES STEADY OR SLOWLY FALLING FROM THIS TIME FORWARD...STILL ABOVE NORMAL! && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/... COLD AIR ADVECTION WITH GUSTY NORTHWEST WINDS 20-30 MPH ASSOCIATED WITH A DEEPENING BOUNDARY LAYER. THE COLD AIR ADVECTION WIND AND VARIABLE CLOUD COVER IS A RESPONSE TO THE 200M 12 HR 500MB HFC CROSSING PA/NJ. T1-T5 LAPSE RATES INCREASE TO 13C BY DAYBREAK SATURDAY. WE NOTE SOME MODELS (UKMET/NSSL WRF) TRYING TO BRING SNOW SHOWERS AND FLURRIES ACROSS NE PA AND NNJ LATE TONIGHT AND WE BELIEVE THIS IS CORRECT. NOTICED A LITTLE VERTICAL DEVELOPMENT IN THE RH FIELD AROUND 06Z SO THAT COULD BE A BURST OF FLURRIES NEAR AND N OF I-78. OUR STORM TOTAL SNOW GRIDS ARE PUBLISHED AND POSTED ON OUR MOUNT HOLLY WEB SITE AS WELL AS PROBS FOR GREATER THAN A TRACE AND THE WORST CASE (90 PERCENTILE) SCENARIO. WE MAY NEED AN SPS FOR SLIPPERY ROADS IN MONROE COUNTY EARLY SATURDAY MORNING. BELOW FREEZING IN PHL? COULD BE THE FIRST TIME THIS SEASON ON SATURDAY MORNING BUT RIGHT NOW WE THINK THE BEST CHC IS SUNDAY MORNING. && .LONG TERM /SATURDAY THROUGH THURSDAY/... THE SYNOPTIC SETUP IS COMPRISED OF A STRONG UPPER-LEVEL TROUGH IN THE EAST TO START SATURDAY BEFORE IT LIFTS NORTHEASTWARD LATER SATURDAY INTO SUNDAY. THIS TROUGH DELIVERS MUCH COLDER AIR INTO THE EAST, HOWEVER THE FLOW IS PROGRESSIVE AND THEREFORE THE COLD SHOT IS SHORT IN DURATION. AS ENERGY ACROSS THE WEST MOVES INTO THE CENTRAL PLAINS LATER IN THE WEEKEND, SOME RIDGING RETURNS ACROSS THE EAST. THIS WILL ALLOW A WARMING TREND TO OCCUR NEXT WEEK, WITH POTENTIALLY NEAR RECORD WARMTH STARTING EITHER WEDNESDAY OR THURSDAY. THE EXTENT OF THE WARMTH NEXT WEEK WILL DEPEND ON THE TIMING OF A COUPLE OF COLD FRONTS. THE STRONGEST COLD FRONT LOOKS TO ARRIVE LATE THURSDAY, HOWEVER THERE IS UNCERTAINTY WITH THE AFFECTS AS SOME MODEL GUIDANCE SHOWS A MORE ACTIVE FRONTAL ZONE EARLIER. WE USED A MODEL BLEND SATURDAY THROUGH MONDAY, THEN A 00Z WPC/CONTINUITY BLEND THEREAFTER. SOME ADJUSTMENTS WERE THEN MADE FOLLOWING ADDITIONAL COLLABORATION WITH OUR NEIGHBORING OFFICES. FOR SATURDAY AND SUNDAY...A STRONG UPPER-LEVEL TROUGH SWINGS ACROSS THE EAST SATURDAY BEFORE LIFTING NORTHEASTWARD INTO SUNDAY. THIS FEATURE WILL HAVE MUCH COLDER AIR WITH IT, WITH CAA LINGERING THROUGH SATURDAY MORNING. THIS THEN WEAKENS SATURDAY NIGHT AND THEN TRANSITIONS TO WAA THEREAFTER. THE 850 MB TEMPERATURES ARE FORECAST TO BE IN THE -10C TO -12C RANGE SATURDAY BEFORE MODERATING, THEREFORE A MUCH COLDER DAY IS EXPECTED. THE COMBINATION OF A MUCH COLDER AIRMASS, A TIGHT PRESSURE GRADIENT WITH STRONG HIGH PRESSURE TO OUR SOUTHWEST AND STRONG FLOW WILL RESULT IN BREEZY/WINDY CONDITIONS SATURDAY. THE FORECAST SOUNDINGS SHOW ABOUT 35 KNOTS OF WIND IN THE MIXING LAYER AS THE LOW-LEVEL LAPSE RATES STEEPEN QUITE A BIT. AS A RESULT, GUSTS WERE INCREASED UP TO 30 KNOTS AT THE SURFACE. THE COMBINATION OF TEMPERATURES IN THE 30S AND 40S AND GUSTY WINDS WILL BRING COLD WIND CHILLS INTO THE PICTURE. WHILE THIS COLD SHOT IS NOT VERY SIGNIFICANT FOR THIS TIME OF YEAR, IT WILL BE A SHOCK GIVEN HOW WARM IT HAS BEEN THIS MONTH ESPECIALLY WITH THE GUSTY WINDS FACTORED IN. IT LOOKS LIKE PHILADELPHIA /THE AIRPORT/ FINALLY GETS BELOW 32 DEGREES SATURDAY NIGHT/EARLY SUNDAY MORNING. THE COLD WEST TO NORTHWEST FLOW IS EXPECTED TO RESULT IN LAKE EFFECT SNOW AND SOME OF THIS ACTIVITY SHOULD GET PULLED INTO NORTHEASTERN PENNSYLVANIA SATURDAY, ALLOWING FOR SOME SNOW SHOWERS INTO AT LEAST THE POCONOS. THERE COULD EVEN BE SOME FLURRIES FARTHER SOUTH AND EAST, HOWEVER THE SUB-CLOUD LAYER /DEW POINTS IN THE TEENS SATURDAY/ MAY BE TO DRY WITH A SOUTHERN EXTENT AND THEREFORE DID NOT CARRY A MENTION TO FAR SOUTH AND EAST. IT IS POSSIBLE THAT A SNOW SQUALL GETS TO THE POCONOS AS FORECAST SOUNDINGS SHOW A HIGHER INVERSION HEIGHT THROUGH ABOUT EARLY AFTERNOON BEFORE LOWERING BY LATE AFTERNOON. IN ADDITION, STEEPENING LOW-LEVEL LAPSE RATES ARE FORECAST AND THIS MAY RESULT IN A LITTLE INSTABILITY AND THEREFORE A SQUALL. THE NAM AND GFS HINT AT A BAND ORIGINATING FROM LAKE ERIE EXTENDING EAST TO NEAR THE POCONOS, AND THIS COULD RESULT IN SOME LIGHT SNOW ACCUMULATIONS ESPECIALLY IN THE HIGHER TERRAIN. HIGH PRESSURE THEN BRIEFLY ARRIVES SUNDAY WITH LESS WIND AS THE UPPER- LEVEL TROUGH LIFTS OUT, HOWEVER WE SHOULD START TO HAVE A RETURN FLOW BECOME ESTABLISHED AS THE UPPER-LEVEL FLOW IS PROGRESSIVE. THIS ALLOWS FOR WAA TO OCCUR AND THEREFORE SOME REBOUND IN AFTERNOON TEMPERATURES, ALTHOUGH THIS SHOULD BE SLOWED SOME DUE TO LESS MIXING. FOR MONDAY THROUGH WEDNESDAY...AN UPPER-LEVEL RIDGE ACROSS THE EAST WILL ALLOW FOR MILDER AIR, HOWEVER A SHORT WAVE TROUGH SLIDES NEARBY LATE MONDAY AND TUESDAY. THIS SHOULD SEND A WEAK COLD FRONT TOWARD OUR AREA, HOWEVER THIS BOUNDARY MAY DISSIPATE AS IT MOVES THROUGH LATE TUESDAY INTO WEDNESDAY. OVERALL A WARMER /AND POTENTIALLY CLOUDIER/ PATTERN IS EXPECTED AND THIS COULD RESULT IN NEAR RECORD WARMTH STARTING WEDNESDAY. IT DOES APPEAR THOUGH AS A DISSIPATING FRONT AND SHORT WAVE TROUGH MOVES THROUGH, SOME SHOWERS SHOULD RESULT ESPECIALLY LATE TUESDAY AND WEDNESDAY. AS A RESULT, IT APPEARS WE ARE NOT IN A CLEAN WARM SECTOR HOWEVER THE AIRMASS WILL BE MODERATING QUITE A BIT TUESDAY AND WEDNESDAY. OUR SUPERBLEND TOOL CONTINUES TO BE A BIT COOLER FOR ESPECIALLY WEDNESDAY, AND WE OPTED TO LEAN CLOSER TO THE WPC GUIDANCE ATTM WHICH FAVORS A BIT HIGHER MAXIMUM TEMPERATURES. FOR THURSDAY...A RIDGE OFF THE SOUTHEAST U.S. COAST SHOULD MAINTAIN A RATHER MILD FLOW ACROSS THE EAST. WHILE THERE ARE SOME TIMING DIFFERENCES IN THE GUIDANCE, THE AIRMASS IS FORECAST TO BE WARM HOWEVER CLOUDINESS COULD TEMPER THE OBSERVED WARMING. IF THERE IS ENOUGH SUNSHINE AND THE COLD FRONT IS DELAYED, THEN RECORD WARMTH COULD OCCUR AT LEAST FOR SOME PARTS OF THE AREA. WE LEANED CLOSER TO THE WPC GUIDANCE WHICH SHOWS A SLOWER ARRIVAL OF A STRONGER COLD FRONT BUT MAINTAINED A CHC FOR SHOWERS. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY, AND SURROUNDING AREAS. TODAY...VFR CIGS AOA 4000 FT WITH A PERIOD OR TWO OF SHOWERS OR SPRINKLES BETWEEN 13Z AND 17Z AT KMIV AND KACY. A TENDENCY FOR THE MORNING OVERCAST TO BECOME SCT-BKN DURING THE AFTERNOON AND AT THAT TIME NORTHWEST WIND GUSTS SHOULD INCREASE TO BETWEEN 20 AND 25 KT. THE DAYBREAK GUSTS SEEM TO BE ASSOCIATED WITH A PULSE OF DRY AIR ADVECTION. TONIGHT...VFR SCT-BKN AOA 4000 FT WITH NORTHWEST WIND GUSTS OCCASIONALLY 20-25 KT. SCATTERED FLURRIES NEAR AND NORTH OF KTTN AND KABE BETWEEN 03Z AND 07Z/19. HIGH CONFIDENCE. OUTLOOK... SATURDAY...VFR. WEST-NORTHWEST 15-20 KNOTS WITH GUSTS TO 30 KNOTS, THEN DIMINISHING AT NIGHT TO 10 KNOTS OR LESS. SUNDAY AND MONDAY..VFR SUNDAY, THEN POSSIBLY LOWERING TO MVFR DURING MONDAY WITH A CHANCE FOR SOME SHOWERS ESPECIALLY AT NIGHT. WEST WINDS MAINLY 5-15 KNOTS, BECOMING SOUTHWEST. TUESDAY...SUB-VFR CONDITIONS POSSIBLE WITH SOME SHOWERS. && .MARINE... WE DROPPED THE SCA IN LIEU OF THE HIGHER ORDER GLW AND PREVENTING MULTI HEADLINE SAME FORECAST PERIOD RAMP UP. THE SIMPLIFICATION BROADCASTS THE IDEA THAT WE SHOULD VERIFY A DECENT GALE SATURDAY MORNING THAT MAY LINGER INTO SATURDAY EVENING. TODAY...INCREASINGLY W-NW WINDS TODAY WITH GUSTS AROUND 25 KT MID AND LATE AFTERNOON AND THEN THOSE GUSTS INCREASE AT LEAST 10 KT LATE TONIGHT TO AROUND 35 KT, IF NOT SOME ISOLATED 40 KT. COASTAL WATER TEMPS STILL IN THE LOWER TO MID 50S. OUTLOOK... SATURDAY...A MUCH COLDER AIRMASS OVER MILD WATER WILL ALLOW FOR A DEEP BOUNDARY LAYER AND EFFICIENT MIXING. THE FORECAST SOUNDINGS SHOW UP TO 40 KNOTS AT THE TOP OF THE MIXED LAYER AND THEREFORE GALES ARE EXPECTED. THE GALE WATCH HAS BEEN UPGRADED TO A WARNING WHICH RUNS THROUGH LATE EVENING FOR THE ATLANTIC COASTAL WATERS AND UNTIL EARLY EVENING FOR DELAWARE BAY. THE WEST-NORTHWEST FLOW SHOULD ALSO FUNNEL DOWN DELAWARE BAY. THE GUSTY WINDS WILL RESULT IN ELEVATED SEAS, HOWEVER THE STRONG OFFSHORE FLOW WILL HELP PUSH THE HIGHER SETS FARTHER AWAY FROM THE COAST. THE WINDS ARE EXPECTED TO DIMINISH DURING SATURDAY NIGHT. SUNDAY AND MONDAY...BELOW SMALL CRAFT ADVISORY CRITERIA SUNDAY AS HIGH PRESSURE BRIEFLY MOVES ACROSS THE AREA, THEN INCREASING SOUTHWESTERLY FLOW MONDAY COULD GUST TO ADVISORY CRITERIA ESPECIALLY ON THE ATLANTIC WATERS. THIS IS OF LOWER CONFIDENCE GIVEN THE AIRMASS WILL BE WARMING. THE STRENGTH OF THE WIND WILL ALSO IMPACT THE SEA HEIGHTS. TUESDAY...THE CONDITIONS ARE ANTICIPATED TO BE BELOW SMALL CRAFT ADVISORY CRITERIA. && .CLIMATE... **DECEMBERS RECORD WARMTH IS LIKELY TO BE REINFORCED WITH MORE DAILY RECORDS TOWARD CHRISTMAS** THE PROCESS OF POSTING RECORD MAXIMUM TEMPERATURES THAT MAY BE APPROACHED OR EXCEEDED CONTINUES, AS OUR FORECAST NUMBERS AND OR MODEL OUTPUT STATISTICAL GUIDANCE (SOMETIMES REFERRED TO AS MOS OR STAT GUIDE) APPROACH WITHIN 2F OR EXCEED THOSE RECORDS. IF YOU REMEMBER, TEMPERATURES PEAKED GENERALLY IN THE 60S ON DECEMBER 24-25 LAST YEAR AND AROUND DECEMBER 21-23 2013 (60S) AS WELL. RECORD DAILY MAX TEMPERATURES BELOW 12/23 12/24 ACY 65-1990 65-1982 PHL 66-1990 64-2014, 1990 ILG 66-1990 65-2014 ABE 64-1990 62-1990 TTN 70-1891 63-2014, 1990 GED 68-2013, 1949 69-2014 RDG 63-2007, 1990 63-1990 MPO 58-1990 62-1990 ALSO... WE MAY EXCEED RECORDS FOR DECEMBER 25 AT MIDNIGHT THAT MORNING, ALTHOUGH THE RECORDS FOR THE 25TH ARE SLIGHTLY LESS VULNERABLE THAN THOSE OF THE 24TH...IN OTHER WORDS THE RECORDS ON THE 25TH ARE SEVERAL DEGREES WARMER THAN THOSE OF THE 24TH. MUCH OF THE REMAINDER OF THIS DISCUSSION WILL PROBABLY BE DISCONTINUED IN LATER AFD`S. WHEN I RETURN, I`LL TAKE A CLOSER LOOK EACH DAY THE 25TH-27TH. TEMPERATURES HAVE BEEN SO WARM THE FIRST 17 DAYS OF THE MONTH (9 TO ALMOST 14 DEGREES ABOVE NORMAL) THAT IT WILL TAKE QUITE A SUBSTANTIAL COLD SPELL TO PREVENT A RECORD WARM DECEMBER, AND THIS AFTER A TOP 8 WARMEST NOVEMBER ON RECORD. GEFS AND EC ENSEMBLES CONTINUE DIRECTING US TO RECORD WARMTH DAILY VALUES TOWARD CHRISTMAS. THEREAFTER, THE 00Z/18 GEFS CONTINUES A NOTABLE EAST COAST RIDGE! FAST WESTERLY FLOW ACROSS THE NORTH ATLANTIC AND NO SIGN OF SUBSTANTIAL RIDGING IN WESTERN NORTH AMERICA OR ANY DEPRESSED JET ACROSS THE SOUTHERN USA ALL SUGGEST THAT BELOW NORMAL COLD IS NOT LIKELY HERE FOR MORE THAN A DAY OR 2 (IF THAT), BETWEEN NOW AND THE NEW YEAR. UNTIL SOMETHING WITHIN THAT OVERALL PATTERN CHANGES SUBSTANTIALLY, GENERALLY ABNORMALLY MILD WEATHER CONTINUES. THE LACK OF SNOW COVER ALSO CONTRIBUTES TO THE POSITIVE DAILY DEPARTURE FROM CLIMATOLOGY. PROJECTIONS EVALUATED WITH THIS MORNINGS 330 AM FRIDAY DECEMBER 18 FORECAST ARE EASILY 8 TO 11 DEGREES ABOVE NORMAL FOR THE ENTIRE MONTH WITH ALMOST 3 DEGREES OF CUSHION ABOVE THE PREVIOUS RECORD . DECEMBER PROJECTED BELOW ABE NORMAL DECEMBER AVERAGE TEMPERATURE IS 32.3. WE ARE EXPECTING AT LEAST 43.0. THIS SHOULD BE THE WARMEST EVER, SINCE RECORDS BEGAN IN 1922, AND 3 DEGREES WARMER THAN THE PREVIOUS WARMEST, DECEMBER 1923, WHEN THE AVERAGE WAS 40.0 PHL NORMAL DECEMBER AVERAGE TEMPERATURE IS 37.5. WE ARE EXPECTING AT LEAST 47.0. THAT SHOULD BE THE WARMEST SINCE TEMPERATURE RECORDS BEGAN IN 1874 (PRECIP RECORDS BEGAN THERE IN 1872). AND THIS WOULD BE ALMOST 3 DEGREES WARMER THAN THE PREVIOUS WARMEST DECEMBER 1923, WHEN THE AVERAGE WAS 44.5 DEGREES. THESE VALUES WERE CALCULATED USING OUR PHI 09Z/18 FORECAST THROUGH D7, THEN ADDING ON THE D8-11 TEMPS FROM THE 00Z/18 NMCFTPRHA (GFS 2M MAX/MIN TEMPS) AND FINALLY, FOR THE LAST 3 DAYS OF THE MONTH, WE JUST USED STRAIGHT DAILY NORMALS FOR EACH LOCATION. THE NUMBERS ABOVE WILL VARY FROM CURRENTLY PROJECTED... AND WE COULD SEE CHANGES OF 2 DEGREES EITHER WAY, BUT OVERALL WHEN ALL THE DAILIES ARE AVERAGED... WE WILL PROBABLY EXPERIENCE OUR WARMEST DECEMBER ON RECORD, THROUGH 2015. THE VALUES POSTED HERE MAY BE CONSERVATIVELY TOO COOL. PHL HAS NOT BEEN BELOW NORMAL SINCE NOV 24TH. PHILADELPHIA`S FIRST SUBFREEZING TEMPERATURE OF THE COOL SEASON SHOULD OCCUR EITHER SATURDAY MORNING OR MORE LIKELY SUNDAY MORNING...THE LAST DAY OF FALL (DEC 20), EASILY EXCEEDING THE PREVIOUS LATEST SUBFREEZING DATE OF DECEMBER 12 1998. OFFICIAL TEMPERATURE RECORDS FOR PHILADELPHIA DATE BACK TO 1874. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...GALE WARNING FROM MIDNIGHT TONIGHT TO 10 PM EST SATURDAY FOR ANZ450>455. GALE WARNING FROM MIDNIGHT TONIGHT TO 7 PM EST SATURDAY FOR ANZ430-431. && $$ SYNOPSIS...GORSE NEAR TERM...DRAG 653 SHORT TERM...DRAG 653 LONG TERM...GORSE AVIATION...DRAG/GORSE 653 MARINE...DRAG/GORSE 653 CLIMATE...653
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
950 AM EST FRI DEC 18 2015 .DISCUSSION... ...HAZARDOUS BOATING CONDITIONS DEVELOPING BEHIND FRONT TODAY... ...NOTICEABLY COLDER TEMPERATURES TONIGHT BUT COOL DOWN WILL BE BRIEF... CURRENT...RADARS DETECTING TWO DISTINCT LINES OF SHOWERS MOVING ACROSS CENTRAL FLORIDA. THE FIRST ONE JUST CLEARING THE ORLANDO AREA AND THE SECOND LINE OF SHOWERS ENTERING LAKE AND NORTHWEST VOLUSIA COUNTIES. AWIPS DISTANCE SPEED TOOL CALCULATED FORWARD MOTION AT AROUND 20 TO 25 MPH. THIS SPEED LOOKS REASONABLE CONSIDERING THAT THE VERTICAL WIND PROFILERS AT THE SPACE CENTER WERE DETECTING SOUTHWEST WINDS AROUND 30 KNOTS FROM JUST OFF THE SURFACE (AROUND 1000 FEET) TO 10,000 FEET. THE 7AM CAPE CANAVERAL UPPER AIR SOUNDING SHOWED WARM TEMPERATURES...AROUND -5C...IN THE MID LEVELS AND A WEAK TEMPERATURE INVERSION JUST BELOW 500MB. ALTHOUGH THE PROSPECTS FOR STORMS IS LOOKING LESS WILL HOLD ON TO THE MENTION OF A SLIGHT CHANCE FOR THE SOUTHERN AREAS FOR THE AFTERNOON AS THE LINE OF SHOWERS WORKS ITS WAY INTO A SLIGHTLY MORE FAVORABLE ENVIRONMENT. WILL REMOVE THUNDER TO THE NORTH. REST OF TODAY(FRIDAY)...RADAR TREND INDICATING THAT THE RAIN WILL END IN NORTH LAKE AND NORTHWEST VOLUSIA COUNTIES BY NOON AND NORTH TO SOUTH THE REST OF THE DAY. SHORT TERM MODELS...HRRR AND WRFARW6... IN CLOSE AGREEMENT WITH THE RADAR TREND. BOTH MODELS INDICATING THAT THE MOISTURE RIBBON WILL CLEAR OKEECHOBEE AND MARTIN COUNTIES AROUND SUNSET 00Z. WIND SHIFTS TO THE NORTHWEST IN THE AFTERNOON AND BEGINS TO ADVECT A COOLER AND DRIER AIR MASS INITIALLY LAKE AND VOLUSIA COUNTIES THEN SOUTH THE REST OF THE DAY. LOCATIONS NORTH OF INTERSTATE 4 PROBABLY HAVE REACHED THEIR HIGHS FOR THE DAY BEFORE NORTHWEST WINDS BEGIN TO PUSH THE COOLER AIR INTO THE AREA. LOW 70S ORLANDO AREA DUE TO CLOUD COVER AND THE WIND SHIFT BEHIND THE FRONT BRINGING IN COOLER AIR. MID AND UPPER 70S OSCEOLA SOUTH BREVARD SOUTH BECAUSE OF THE LATER FRONTAL PASSAGE AND ARRIVAL OF THE COOLER AIR SPREADING DOWN THE PENINSULA. .AVIATION...IFR/LIFR CEILINGS AHEAD OF THE FRONT BECOMING MVFR/VFR SHORTLY AFTER FRONTAL PASSAGE. .MARINE... CURRENT...BUOY 009 AT 20NM EAST OF CAPE CANAVERAL WAS REPORTING SOUTH TO SOUTHWEST WINDS 15 TO 20 KNOTS AND 3 TO 4 FOOT SEAS. THE TWO SCRIPPS BUOYS AT 4 AND 6NM OFF THE BEACH WERE RECORDING 2 FOOT SEAS. THIS AFTERNOON...WINDS TO SHIFT TO THE WEST THEN NORTHWEST BEHIND THE FRONT AS IT PUSHES DOWN THE COASTAL WATERS. SEAS BUILD TO 5 TO 6 FEET IN THE GULF STREAM OFFSHORE VOLUSIA AND NORTH BREVARD COUNTIES THEN SOUTH THIS EVENING. SMALL CRAFT ADVISORY FLAGLER BEACH TO SEBASTIAN INLET THIS AFTERNOON A GOOD CALL. PREVIOUS AFD ISSUED AT 411 AM EST FRI DEC 18 2015 CURRENT...STRONG COLD FRONT CURRENTLY OVER NORTH FLORIDA THIS MORNING WITH A PRE-FRONTAL BAND OF LIGHT/MODERATE SHOWERS EXTENDING FROM ST. AUGUSTINE SOUTHWESTWARD THROUGH LAKE COUNTY AND DOWN TO SARASOTA. UNSEASONABLY WARM TEMPERATURES PRESENTLY WITH U60S TO L70S ACROSS EAST CENTRAL FLORIDA. VERY MOIST SURFACE DEWPOINTS AS WELL AND GENERALLY WITHIN 3 DEGREES OF TEMPERATURES AREAWIDE. WINDS WERE LIGHT S/SWRLY. CAPE WIND PROFILERS SHOW DEEPENING SOUTHWESTERLY FLOW WITH STRONGER 20 TO 30 KNOT WINDS BETWEEN 3.0-10.0 KFT. TODAY...EXPECT CLOUD COVER TO THICKEN FROM THE NORTH TO SOUTH THIS MORNING WITH THE APPROACH OF THE COLD FRONT AND ASSOCIATED BAND OF CONVECTION. A THIN BAND OF PRECIPITABLE WATER VALUES AROUND 2 INCHES WILL POOL ALONG AND JUST AHEAD OF THE FRONT. LOCAL HRRR MODEL RUN SUGGESTS CONVECTION (GREATEST CHANCES) ACROSS OUR NORTHERN COUNTIES NEAR/SHORTLY AFTER SUNRISE...ACROSS THE ORLANDO METRO MID/LATE MORNING...BREVARD/OSCEOLA COUNTIES LATE MORNING/EARLY AFTERNOON AND OKEECHOBEE COUNTY/TREASURE COAST ANYWHERE FROM EARLY-LATE AFTERNOON. WHILE THE LINE PRESSES SOUTHEASTWARD AHEAD OF THE FRONT THROUGH THE DAY INDIVIDUAL CELLS WITHIN BAND OF CONVECTION OR OUT AHEAD OF IT WILL TRAVEL FROM THE SOUTHWEST TOWARD THE NORTHEAST AT AROUND 30 MPH. RAINFALL AMOUNTS WILL LIKELY AVERAGE 0.25" TO 0.50" WITH ISOLATED HIGHER AMOUNTS POSSIBLE FALLING OVER A 1-3HR WINDOW. HAVE BROAD- BRUSHED A 70-80 PERCENT CHANCE FOR PRECIPITATION ACROSS THE FORECAST AREA...THOUGH THE WHOLE DAY WILL NOT BE A WASHOUT. AN ISOLATED THREAT FOR LIGHTNING STORMS WILL ALSO BE POSSIBLE. STRONGEST TROUGHING/SHORTWAVE ENERGY WILL REMAIN NORTH OF FLORIDA AS WARMER TEMPERATURES ALOFT AT 700-500MB WILL LIMIT OVERALL DESTABILIZATION OF THE ATMOSPHERE. ASIDE FROM MOISTURE...WHAT THIS SYSTEM HAS GOING FOR IT WILL BE DECENT DIFFLUENCE ALOFT (250MB) FROM THE RIGHT-REAR QUADRANT OF THE UPPER JET (100-120KTS) OVER NORTH FLORIDA. GUSTY WINDS...OCCASIONAL LIGHTNING...LOCALLY HEAVY DOWNPOURS WILL BE THE MAIN THREATS AND SEVERE WEATHER IS NOT ANTICIPATED. EARLY MORNING SSWRLY WINDS WILL CONTINUE TO VEER THROUGH THE DAY AHEAD/BEHIND THE BOUNDARY BECOMING NW MOST EVERYWHERE BY SUNSET. WIND SPEEDS MAY BECOME BREEZY AT TIMES AND OCCASIONALLY GUSTY IN THE AFTERNOON. TEMPERATURES AT SUNRISE ALONG/NORTH OF I-4 (L70S) LIKELY TO BE THE HIGHEST FOR THE DAY WITH FALLING TEMPERATURES HERE THROUGH THE MORNING AND AFTERNOON. M70S FOR HIGHS FURTHER SOUTH ACROSS THE INTERIOR. M-U70S ACROSS THE SPACE COAST WITH U70S TO L80S ALONG THE TREASURE COAST WHERE THICKER CLOUDS/PRECIPITATION MAY NOT REACH UNTIL EARLY/MID AFTERNOON. TONIGHT...THE COLDEST AIR OF THE LATE AUTUMN SEASON IS EXPECTED. OVERNIGHT LOWS WILL FALL INTO THE L-M40S ALONG/NORTH OF I-4. U40S TO AROUND 50 DEGREES SOUTHWARD THROUGH THE INTERIOR TOWARD LAKE OKEECHOBEE. THE SPACE AND TREASURE COASTS WILL REALIZE LOWS IN THE L-M50S ON AVERAGE...EXCEPT L60S POSSIBLE ALONG THE IMMEDIATE MARTIN COUNTY COAST. NW/N WINDS ARE FORECAST TO REMAIN ELEVATED AS THE PRESSURE GRADIENT REMAINS STOUT WITH SPEEDS IN UPWARDS OF AROUND 15 MPH AND OCCASIONALLY GUSTY. ODDLY ENOUGH TOO...LOWEST WIND CHILL READINGS VERY LATE TONIGHT WILL FALL INTO THE U30S FOR 1-3HRS NORTH OF I-4...THOUGH A WIND CHILL ADVISORY WILL NOT BE NEEDED. MUCH DRIER AIR WILL ALSO FILTER DOWN THE PENINSULA BEHIND THE FRONT. SAT-SAT NIGHT...FAIRLY STRONG SURFACE HIGH PRESSURE CENTERED OVER THE GULF COAST STATES WILL ADVANCE E/NE REACHING THE MID ATLC COAST SUN MORNING. AFTER A CHILLY START FOR MOST AREAS...HIGHS WILL GET BACK CLOSE TO NORMAL...MID-UPPER 60S ORLANDO NORTH TO MID 70S MARTIN COUNTY. A QUICK RETURN OF MARINE MODIFIED AIR WILL NOT ALLOW TEMPS TO FALL AS MUCH SAT NIGHT...MID-UPPER 40S FAR NORTH... LOWER 50S ALG I 4 CORRIDOR AND UPPER 50S SPACE/TREASURE COAST... EXCEPT MID 60S ALONG THE BEACHES. SUN-CHRISTMAS EVE...MODERATING TEMPERATURES/MOISTURE VALUES THROUGH THE PERIOD. SURFACE HIGH PRESSURE WILL MOVE OFF THE SOUTHEAST U.S. COAST AND INTO THE ATLANTIC EARLY NEXT WEEK WITH CENTER BECOMING ANCHORED NEAR BERMUDA. THE RIDGE AXIS WILL GRADUALLY SETTLE INTO THE STATE AND CAUSE BREEZY ONSHORE FLOW TO VEER TO THE SOUTH TOWARDS MID WEEK. THE 00Z GFS REMAINS MUCH MORE MOIST THAN THE ECMWF...SHOWING AREAWIDE POPS STARTING MON AND CONTINUING THROUGH THE PERIOD. WILL GO CLOSE TO CONSENSUS POPS WHICH ARE SIMILAR TO THE PREVIOUS FORECAST (20-40 PERCENT) AND KEEP OUT MENTION OF THUNDER FOR NOW. TEMPERATURES ARE FORECAST TO RETURN TO NORMAL OR SLIGHTLY ABOVE ON SUNDAY...FOLLOWED BY MUCH ABOVE NORMAL TEMPS EARLY-MID NEXT WEEK WITH POTENTIAL FOR MORE RECORD WARMTH. && .AVIATION... MVFR/IFR CONDS POSSIBLE EARLY THIS MORNING. STRONG FRONT TO MOVE THROUGH CENTRAL FL TODAY PRECEDED BY SHOWERS AND PERHAPS AN ISOLD STORM. TEMPO IFR CONDS WITH CONVECTION. SW WINDS AHEAD OF THE BOUNDARY WILL BECOME NWRLY BEHIND IT. BREEZY/GUSTY AT TIMES IN THE AFTERNOON. NW WINDS REMAIN ELEVATED TONIGHT AS COLDER/DRIER CONDS FILTER DOWN THE PENINSULA. VFR BEHIND THE FRONT LATER TODAY (NORTH TO SOUTH) AND TONIGHT. && .MARINE... TODAY-TONIGHT...A STRONG COLD FRONT WILL PASS ACROSS THE WATERS DURING THE DAY PRECEDED BY SHOWERS/ISOLD LIGHTNING STORMS. GUSTY WINDS/DOWNPOURS ALSO LIKELY WITH QUICK OFFSHORE MOVING CONVECTION. SOUTHWEST WINDS WILL VEER TO NW BEHIND THE FRONT THROUGH THE DAY/EVENING WITH SPEEDS INCREASING 20-25 KTS OFFSHORE/20 KTS NEAR SHORE. WIND DIRECTION WILL BECOME MORE NORTHERLY TO NNE AFTER MIDNIGHT. SEAS WILL BE SLOWER TO BUILD. AT PRESS TIME...CURRENT 2-4 FT SEAS NEAR SHORE/3-5 FT SEAS OFFSHORE WILL STEADILY BUILD THRU LATE DAY TO 3-5 FT NEAR SHORE/SOUTH OFFSHORE MARINE LEG...AND 5-6 FT OFFSHORE NORTH OF SEBASTIAN INLET. SEAS CONTINUE TO BUILD TONIGHT TO 6-8 FT NEAR SHORE AND 7-10 FT GULF STREAM/OFFSHORE. SHOWER/ISOLD STORM ACTIVITY SHOULD CLEAR THE SOUTHERN COASTAL WATERS DURING THE EARLY-MID EVENING. A SMALL CRAFT ADVISORY WILL GO INTO EFFECT AT 09Z/4AM NORTH OF SEBASTIAN INLET OFFSHORE...BRINGING IT NEAR SHORE NORTH OF SEBASTIAN INLET AT 18Z/1PM...THEN EXPANDING SOUTHWARD TO JUPITER INLET BY 21Z/4PM. CAUTIONARY STATEMENTS LIKELY TO ACCOMPANY EARLY MORNING CWF ISSUANCE NEAR SHORE NORTH OF SEBASTIAN INLET/OFFSHORE SEBASTIAN INLET-JUPITER INLET AS SWRLY WINDS INCREASE AHEAD OF THE APPROACHING STRONG FRONT. SAT-TUE...WINDS ARE FORECAST TO VEER TO THE NORTHEAST AND CONTINUE AROUND 20 KNOTS ON SAT. MODELS TEND TO VEER THE WINDS TOO QUICKLY IN THESE SCENARIOS AND THE WIND DIRECTION MAY BE MORE BACKED FROM THE N OR N/NE. REGARDLESS...HAZARDOUS BOATING CONDITIONS WILL EXIST...ESPECIALLY IN THE GULF STREAM WHERE SEAS OF 10 FEET ARE FORECAST. THE WIND DIRECTION WILL GRADUALLY VEER TO THE EAST ON SUNDAY AS HIGH PRESSURE PUSHES OFF THE MID ATLC COAST BUT PRESSURE GRADIENT WILL STILL SUPPORT NEAR 20 KNOTS ACROSS THE CENTRAL AND SOUTHERN WATERS...15 KNOTS ACROSS THE NORTH. THERE WILL BE JUST A SLIGHT DIMINISHING OF WINDS/SEAS MON-TUE AS FLOW VEERS OUT OF THE SOUTHEAST. && .PRELIMINARY POINT TEMPS/POPS... DAB 73 46 67 53 / 80 0 0 0 MCO 74 48 69 53 / 80 0 0 0 MLB 77 52 70 60 / 70 10 0 10 VRB 79 56 72 61 / 80 10 0 10 LEE 72 44 67 48 / 80 0 0 0 SFB 73 47 69 53 / 80 0 0 0 ORL 73 49 68 54 / 80 0 0 0 FPR 78 54 72 62 / 70 10 0 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 PM EST SUNDAY FOR FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 0-20 NM- VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 0-20 NM. SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 4 PM EST SUNDAY FOR SEBASTIAN INLET TO JUPITER INLET 0-20 NM-SEBASTIAN INLET TO JUPITER INLET 20-60 NM. SMALL CRAFT ADVISORY UNTIL 4 PM EST SUNDAY FOR FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 20-60 NM-VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 20-60 NM. && $$ LONG TERM/IMPACT WX...LASCODY SHORT TERM/AVIATION...WIMMER
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
411 AM EST FRI DEC 18 2015 .DISCUSSION... ...HAZARDOUS BOATING CONDITIONS DEVELOPING BEHIND FRONT TODAY... ...NOTICEABLY COLDER TEMPERATURES TONIGHT BUT COOL DOWN WILL BE BRIEF... CURRENT...STRONG COLD FRONT CURRENTLY OVER NORTH FLORIDA THIS MORNING WITH A PRE-FRONTAL BAND OF LIGHT/MODERATE SHOWERS EXTENDING FROM ST. AUGUSTINE SOUTHWESTWARD THROUGH LAKE COUNTY AND DOWN TO SARASOTA. UNSEASONABLY WARM TEMPERATURES PRESENTLY WITH U60S TO L70S ACROSS EAST CENTRAL FLORIDA. VERY MOIST SURFACE DEWPOINTS AS WELL AND GENERALLY WITHIN 3 DEGREES OF TEMPERATURES AREAWIDE. WINDS WERE LIGHT S/SWRLY. CAPE WIND PROFILERS SHOW DEEPENING SOUTHWESTERLY FLOW WITH STRONGER 20 TO 30 KNOT WINDS BETWEEN 3.0-10.0 KFT. TODAY...EXPECT CLOUD COVER TO THICKEN FROM THE NORTH TO SOUTH THIS MORNING WITH THE APPROACH OF THE COLD FRONT AND ASSOCIATED BAND OF CONVECTION. A THIN BAND OF PRECIPITABLE WATER VALUES AROUND 2 INCHES WILL POOL ALONG AND JUST AHEAD OF THE FRONT. LOCAL HRRR MODEL RUN SUGGESTS CONVECTION (GREATEST CHANCES) ACROSS OUR NORTHERN COUNTIES NEAR/SHORTLY AFTER SUNRISE...ACROSS THE ORLANDO METRO MID/LATE MORNING...BREVARD/OSCEOLA COUNTIES LATE MORNING/EARLY AFTERNOON AND OKEECHOBEE COUNTY/TREASURE COAST ANYWHERE FROM EARLY-LATE AFTERNOON. WHILE THE LINE PRESSES SOUTHEASTWARD AHEAD OF THE FRONT THROUGH THE DAY INDIVIDUAL CELLS WITHIN BAND OF CONVECTION OR OUT AHEAD OF IT WILL TRAVEL FROM THE SOUTHWEST TOWARD THE NORTHEAST AT AROUND 30 MPH. RAINFALL AMOUNTS WILL LIKELY AVERAGE 0.25" TO 0.50" WITH ISOLATED HIGHER AMOUNTS POSSIBLE FALLING OVER A 1-3HR WINDOW. HAVE BROAD- BRUSHED A 70-80 PERCENT CHANCE FOR PRECIPITATION ACROSS THE FORECAST AREA...THOUGH THE WHOLE DAY WILL NOT BE A WASHOUT. AN ISOLATED THREAT FOR LIGHTNING STORMS WILL ALSO BE POSSIBLE. STRONGEST TROUGHING/SHORTWAVE ENERGY WILL REMAIN NORTH OF FLORIDA AS WARMER TEMPERATURES ALOFT AT 700-500MB WILL LIMIT OVERALL DESTABILIZATION OF THE ATMOSPHERE. ASIDE FROM MOISTURE...WHAT THIS SYSTEM HAS GOING FOR IT WILL BE DECENT DIFFLUENCE ALOFT (250MB) FROM THE RIGHT-REAR QUADRANT OF THE UPPER JET (100-120KTS) OVER NORTH FLORIDA. GUSTY WINDS...OCCASIONAL LIGHTNING...LOCALLY HEAVY DOWNPOURS WILL BE THE MAIN THREATS AND SEVERE WEATHER IS NOT ANTICIPATED. EARLY MORNING SSWRLY WINDS WILL CONTINUE TO VEER THROUGH THE DAY AHEAD/BEHIND THE BOUNDARY BECOMING NW MOST EVERYWHERE BY SUNSET. WIND SPEEDS MAY BECOME BREEZY AT TIMES AND OCCASIONALLY GUSTY IN THE AFTERNOON. TEMPERATURES AT SUNRISE ALONG/NORTH OF I-4 (L70S) LIKELY TO BE THE HIGHEST FOR THE DAY WITH FALLING TEMPERATURES HERE THROUGH THE MORNING AND AFTERNOON. M70S FOR HIGHS FURTHER SOUTH ACROSS THE INTERIOR. M-U70S ACROSS THE SPACE COAST WITH U70S TO L80S ALONG THE TREASURE COAST WHERE THICKER CLOUDS/PRECIPITATION MAY NOT REACH UNTIL EARLY/MID AFTERNOON. TONIGHT...THE COLDEST AIR OF THE LATE AUTUMN SEASON IS EXPECTED. OVERNIGHT LOWS WILL FALL INTO THE L-M40S ALONG/NORTH OF I-4. U40S TO AROUND 50 DEGREES SOUTHWARD THROUGH THE INTERIOR TOWARD LAKE OKEECHOBEE. THE SPACE AND TREASURE COASTS WILL REALIZE LOWS IN THE L-M50S ON AVERAGE...EXCEPT L60S POSSIBLE ALONG THE IMMEDIATE MARTIN COUNTY COAST. NW/N WINDS ARE FORECAST TO REMAIN ELEVATED AS THE PRESSURE GRADIENT REMAINS STOUT WITH SPEEDS IN UPWARDS OF AROUND 15 MPH AND OCCASIONALLY GUSTY. ODDLY ENOUGH TOO...LOWEST WIND CHILL READINGS VERY LATE TONIGHT WILL FALL INTO THE U30S FOR 1-3HRS NORTH OF I-4...THOUGH A WIND CHILL ADVISORY WILL NOT BE NEEDED. MUCH DRIER AIR WILL ALSO FILTER DOWN THE PENINSULA BEHIND THE FRONT. SAT-SAT NIGHT...FAIRLY STRONG SURFACE HIGH PRESSURE CENTERED OVER THE GULF COAST STATES WILL ADVANCE E/NE REACHING THE MID ATLC COAST SUN MORNING. AFTER A CHILLY START FOR MOST AREAS...HIGHS WILL GET BACK CLOSE TO NORMAL...MID-UPPER 60S ORLANDO NORTH TO MID 70S MARTIN COUNTY. A QUICK RETURN OF MARINE MODIFIED AIR WILL NOT ALLOW TEMPS TO FALL AS MUCH SAT NIGHT...MID-UPPER 40S FAR NORTH... LOWER 50S ALG I 4 CORRIDOR AND UPPER 50S SPACE/TREASURE COAST... EXCEPT MID 60S ALONG THE BEACHES. SUN-CHRISTMAS EVE...MODERATING TEMPERATURES/MOISTURE VALUES THROUGH THE PERIOD. SURFACE HIGH PRESSURE WILL MOVE OFF THE SOUTHEAST U.S. COAST AND INTO THE ATLANTIC EARLY NEXT WEEK WITH CENTER BECOMING ANCHORED NEAR BERMUDA. THE RIDGE AXIS WILL GRADUALLY SETTLE INTO THE STATE AND CAUSE BREEZY ONSHORE FLOW TO VEER TO THE SOUTH TOWARDS MID WEEK. THE 00Z GFS REMAINS MUCH MORE MOIST THAN THE ECMWF...SHOWING AREAWIDE POPS STARTING MON AND CONTINUING THROUGH THE PERIOD. WILL GO CLOSE TO CONSENSUS POPS WHICH ARE SIMILAR TO THE PREVIOUS FORECAST (20-40 PERCENT) AND KEEP OUT MENTION OF THUNDER FOR NOW. TEMPERATURES ARE FORECAST TO RETURN TO NORMAL OR SLIGHTLY ABOVE ON SUNDAY...FOLLOWED BY MUCH ABOVE NORMAL TEMPS EARLY-MID NEXT WEEK WITH POTENTIAL FOR MORE RECORD WARMTH. && .AVIATION... MVFR/IFR CONDS POSSIBLE EARLY THIS MORNING. STRONG FRONT TO MOVE THROUGH CENTRAL FL TODAY PRECEDED BY SHOWERS AND PERHAPS AN ISOLD STORM. TEMPO IFR CONDS WITH CONVECTION. SW WINDS AHEAD OF THE BOUNDARY WILL BECOME NWRLY BEHIND IT. BREEZY/GUSTY AT TIMES IN THE AFTERNOON. NW WINDS REMAIN ELEVATED TONIGHT AS COLDER/DRIER CONDS FILTER DOWN THE PENINSULA. VFR BEHIND THE FRONT LATER TODAY (NORTH TO SOUTH) AND TONIGHT. && .MARINE... TODAY-TONIGHT...A STRONG COLD FRONT WILL PASS ACROSS THE WATERS DURING THE DAY PRECEDED BY SHOWERS/ISOLD LIGHTNING STORMS. GUSTY WINDS/DOWNPOURS ALSO LIKELY WITH QUICK OFFSHORE MOVING CONVECTION. SOUTHWEST WINDS WILL VEER TO NW BEHIND THE FRONT THROUGH THE DAY/EVENING WITH SPEEDS INCREASING 20-25 KTS OFFSHORE/20 KTS NEAR SHORE. WIND DIRECTION WILL BECOME MORE NORTHERLY TO NNE AFTER MIDNIGHT. SEAS WILL BE SLOWER TO BUILD. AT PRESS TIME...CURRENT 2-4 FT SEAS NEAR SHORE/3-5 FT SEAS OFFSHORE WILL STEADILY BUILD THRU LATE DAY TO 3-5 FT NEAR SHORE/SOUTH OFFSHORE MARINE LEG...AND 5-6 FT OFFSHORE NORTH OF SEBASTIAN INLET. SEAS CONTINUE TO BUILD TONIGHT TO 6-8 FT NEAR SHORE AND 7-10 FT GULF STREAM/OFFSHORE. SHOWER/ISOLD STORM ACTIVITY SHOULD CLEAR THE SOUTHERN COASTAL WATERS DURING THE EARLY-MID EVENING. A SMALL CRAFT ADVISORY WILL GO INTO EFFECT AT 09Z/4AM NORTH OF SEBASTIAN INLET OFFSHORE...BRINGING IT NEAR SHORE NORTH OF SEBASTIAN INLET AT 18Z/1PM...THEN EXPANDING SOUTHWARD TO JUPITER INLET BY 21Z/4PM. CAUTIONARY STATEMENTS LIKELY TO ACCOMPANY EARLY MORNING CWF ISSUANCE NEAR SHORE NORTH OF SEBASTIAN INLET/OFFSHORE SEBASTIAN INLET-JUPITER INLET AS SWRLY WINDS INCREASE AHEAD OF THE APPROACHING STRONG FRONT. SAT-TUE...WINDS ARE FORECAST TO VEER TO THE NORTHEAST AND CONTINUE AROUND 20 KNOTS ON SAT. MODELS TEND TO VEER THE WINDS TOO QUICKLY IN THESE SCENARIOS AND THE WIND DIRECTION MAY BE MORE BACKED FROM THE N OR N/NE. REGARDLESS...HAZARDOUS BOATING CONDITIONS WILL EXIST...ESPECIALLY IN THE GULF STREAM WHERE SEAS OF 10 FEET ARE FORECAST. THE WIND DIRECTION WILL GRADUALLY VEER TO THE EAST ON SUNDAY AS HIGH PRESSURE PUSHES OFF THE MID ATLC COAST BUT PRESSURE GRADIENT WILL STILL SUPPORT NEAR 20 KNOTS ACROSS THE CENTRAL AND SOUTHERN WATERS...15 KNOTS ACROSS THE NORTH. THERE WILL BE JUST A SLIGHT DIMINISHING OF WINDS/SEAS MON-TUE AS FLOW VEERS OUT OF THE SOUTHEAST. && .PRELIMINARY POINT TEMPS/POPS... DAB 73 46 67 53 / 80 0 0 0 MCO 74 48 69 53 / 80 0 0 0 MLB 77 52 70 60 / 70 10 0 10 VRB 79 56 72 61 / 80 10 0 10 LEE 72 44 67 48 / 80 0 0 0 SFB 73 47 69 53 / 80 0 0 0 ORL 73 49 68 54 / 80 0 0 0 FPR 78 54 72 62 / 70 10 0 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 PM EST SUNDAY FOR FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 0-20 NM- VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 0-20 NM. SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 4 PM EST SUNDAY FOR SEBASTIAN INLET TO JUPITER INLET 0-20 NM-SEBASTIAN INLET TO JUPITER INLET 20-60 NM. SMALL CRAFT ADVISORY UNTIL 4 PM EST SUNDAY FOR FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 20-60 NM-VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 20-60 NM. && $$ SHORT TERM...SEDLOCK LONG TERM....KELLY
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1100 PM EST SAT DEC 19 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW && .SYNOPSIS... ISSUED AT 125 PM EST SAT DEC 19 2015 HIGH PRESSURE OVER THE DEEP SOUTH WILL PROVIDE DRY WEATHER FOR CENTRAL INDIANA THROUGH SUNDAY EVENING. SOUTHERLY WINDS WILL RETURN TO CENTRAL INDIANA ON SUNDAY...ALLOWING FOR A WARMER DAY. LOW PRESSURE AND A COLD FRONT APPROACHING THE GREAT LAKES ON LATE SUNDAY NIGHT AND MONDAY WILL BRING CHANCES FOR RAIN SHOWERS BACK TO CENTRAL INDIANA. EARLY NEXT WORK WEEK...SEVERAL UPPER LEVEL WEATHER DISTURBANCES WILL PUSH ACROSS THE REGION...CONTINUING THE CHANCES FOR RAIN. MILD AIR IS EXPECTED TO REMAIN ACROSS THE REGION THROUGH NEXT WEEK. THIS WILL RESULT IN A WARM AND GREEN CHRISTMAS. && .NEAR TERM /OVERNIGHT/... ISSUED AT 944 PM EST SAT DEC 19 2015 CLEAR SKIES ACROSS CENTRAL INDIANA THIS EVENING WITH HIGH PRESSURE CENTERED OVER EASTERN TENNESSEE. WITH LIGHT FLOW AND A DRY AIRMASS...TEMPS HAVE FALLEN QUICKLY THIS EVENING INTO THE MID AND UPPER 20S AT 0230Z. LITTLE CHANGE NEEDED FOR THE EVENING UPDATE AS CURRENT FORECAST IN EXCELLENT SHAPE. WITH ONLY SOME THIN CIRRUS DRIFTING INTO THE REGION FROM THE WEST AFTER MIDNIGHT...MAIN FOCUS IS ON TEMPS THE REST OF THE NIGHT. DECISION TO TREND LOWS TOWARDS THE COOL END OF GUIDANCE WAS A GOOD CALL...AS MANY AREAS ARE ALREADY WITHIN A COUPLE DEGREES OF FORECAST LOWS. EXPECT LOWS TO BE REACHED AROUND OR SHORTLY AFTER 06Z WITH TEMPS STEADYING OR SLOWLY RISING THEREAFTER AS WARM ADVECTION COMMENCES AND SOUTHERLY WINDS STRENGTHEN TOWARDS DAYBREAK. UTILIZED RUC HOURLY DATA FOR TEMPERATURE INTERPOLATION OVERNIGHT WITH TEMPS RECOVERING INTO THE UPPER 20S AND LOWER 30S BY DAYBREAK. ZONE AND GRID UPDATES OUT. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... ISSUED AT 125 PM EST SAT DEC 19 2015 DRY WEATHER WILL CONTINUE TO BE EXPECTED ON SUNDAY AND SUNDAY NIGHT AS WARM AIR ADVECTION CONTINUES THROUGH THE DAY ON SOUTHWEST FLOW ALOFT. MODEL SUGGEST 850MB TEMPS REACHING NEAR 8C BY 00Z MONDAY. TIME HEIGHT SECTIONS THROUGH THE DAY SUGGEST SATURATION ALOFT...THUS WILL TREND TOWARD A PARTLY CLOUDY SKY. GIVEN THE STRONG WARM AIR ADVECTION AND SOUTHWESTERLY FLOW WILL TREND HIGHS AT OR ABOVE MAVMOS. INCREASING CLOUDS WILL BE EXPECTED ON SUNDAY NIGHT AS MODELS SUGGEST A SHORT WAVE EMBEDDED WITHIN THE SOUTHWEST FLOW ALOFT TO PUSH ACROSS THE STATE AFTER 06Z. FORECAST SOUNDINGS AND TIME TIME HEIGHTS INDICATE DEEP SATURATION. THE 300K GFS ISENTROPIC SURFACE SHOWS A SURGE OF MOISTURE WITH SPECIFIC HUMIDITIES REACHING OVER 4 G/KG ALONG WITH GOOD LIFT. THUS RAIN WILL BE EXPECTED ON SUNDAY NIGHT AFTER 06Z...AND WILL TREND POPS AT OR ABOVE GUIDANCE. GIVEN THE CLOUDS AND EXPECTED PRECIP WILL TREND LOWS WARMER THAN MAVMOS. MODELS SUGGEST THAT ON MONDAY THROUGH TUESDAY THE ASSOCIATED LOW PRESSURE SYSTEM WITH THE COLD FRONT PULLS QUICKLY TO THE NORTHEAST WHILE THE COLD FRONT STALLS AND ELONGATES ACROSS CENTRAL INDIANA AND SOUTHERN INDIANA. MEANWHILE ALOFT...MAINLY QUICK ZONAL FLOW REMAINS IN PLACE...ALLOWING A SERIES OF WEAK SHORT WAVES TO PUSH IN TO THE OHIO VALLEY THROUGH TUESDAY. GIVEN THE POOR ORGANIZATION...BUT DECENT FORCING AND A LINGERING BOUNDARY IN PLACE ACROSS THE AREA...SOME LOW CHANCE POPS WILL BE NEEDED...FOR LIGHT PRECIP EVENTS. WILL STICK CLOSE TO MAVMOS POPS THROUGH TUESDAY AND TREND LOWS WARMER THAN MAVMOS AND STICK CLOSE ON HIGHS. && .LONG TERM /TUESDAY NIGHT THROUGH NEXT SATURDAY/... ISSUED AT 216 PM EST SAT DEC 19 2015 ENSEMBLES INDICATE A MEAN UPPER RIDGE OVER THE EASTERN PARTS OF THE COUNTRY AND MEAN TROUGHING OVER THE ROCKIES DURING THIS PERIOD. PERIODIC CHANCES FOR RAIN EXPECTED AS DISTURBANCES EJECT OUT OF THE ROCKIES TROUGH. ONE UPPER WAVE WILL BE PASSING THROUGH THE LOCAL AREA AROUND WEDNESDAY OR THURSDAY MORNING. WILL CONTINUE WITH POPS THROUGH THURSDAY TO COVER THIS FEATURE. ENSEMBLES SUGGEST A DRY PERIOD FROM THURSDAY NIGHT INTO FRIDAY...BEFORE THE POTENTIAL FOR THE NEXT DISTURBANCE TO APPROACH THE AREA FRIDAY INTO NEXT SATURDAY. LARGE DIFFERENCES EXIST AMONG THE ENSEMBLE MEMBERS REGARDING THIS NEXT DISTURBANCE...WITH SOME MEMBERS KEEPING THIS SYSTEM MORE PROGRESSIVE...WHILE OTHERS CUT THIS SYSTEM OFF OVER THE SOUTHWEST. FOR NOW...WILL GO WITH CHANCE POPS FOR FRIDAY AND SATURDAY TO COVER THE MORE PROGRESSIVE SOLUTIONS. && .AVIATION /DISCUSSION FOR THE 200600Z TAF ISSUANCE/... ISSUED AT 1100 PM EST SAT DEC 19 2015 HIGH CONFIDENCE IN VFR CONDITIONS THROUGH AT LEAST 04Z SUNDAY. PER MODEL RH TIME SECTIONS AND SATELLITE TRENDS...SHOULD ONLY SEE INCREASING CIRRUS OVERNIGHT AND TODAY...AS AN UPPER RIDGE PASSES THROUGH RESULTING IN SOUTHWEST FLOW ALOFT. DO NOT EXPECT FOG AS LATE EVENING DEW POINT SPREADS REMAINED ABOVE 5 DEGREES AND SOUTH WINDS WILL INCREASE TO AROUND 6 KNOTS OVERNIGHT. LOWER CLOUDS AND A FEW RAIN SHOWERS ARE EXPECTED TO MOVE IN AFTER 04Z MONDAY AS SOUTHERLY FLOW BRINGS IN MOISTURE OFF THE GULF AHEAD OF A WESTERN GREAT LAKES AND SOUTHERN PLAINS FRONTAL SYSTEM. THE SOUTHERLY WINDS WILL INCREASE AFTER 15Z TO NEAR 15 KNOTS WITH GUSTS TO 20 TO 25 KNOTS. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....JAS AVIATION...MK
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
944 PM EST SAT DEC 19 2015 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW && .SYNOPSIS... ISSUED AT 125 PM EST SAT DEC 19 2015 HIGH PRESSURE OVER THE DEEP SOUTH WILL PROVIDE DRY WEATHER FOR CENTRAL INDIANA THROUGH SUNDAY EVENING. SOUTHERLY WINDS WILL RETURN TO CENTRAL INDIANA ON SUNDAY...ALLOWING FOR A WARMER DAY. LOW PRESSURE AND A COLD FRONT APPROACHING THE GREAT LAKES ON LATE SUNDAY NIGHT AND MONDAY WILL BRING CHANCES FOR RAIN SHOWERS BACK TO CENTRAL INDIANA. EARLY NEXT WORK WEEK...SEVERAL UPPER LEVEL WEATHER DISTURBANCES WILL PUSH ACROSS THE REGION...CONTINUING THE CHANCES FOR RAIN. MILD AIR IS EXPECTED TO REMAIN ACROSS THE REGION THROUGH NEXT WEEK. THIS WILL RESULT IN A WARM AND GREEN CHRISTMAS. && .NEAR TERM /OVERNIGHT/... ISSUED AT 944 PM EST SAT DEC 19 2015 CLEAR SKIES ACROSS CENTRAL INDIANA THIS EVENING WITH HIGH PRESSURE CENTERED OVER EASTERN TENNESSEE. WITH LIGHT FLOW AND A DRY AIRMASS...TEMPS HAVE FALLEN QUICKLY THIS EVENING INTO THE MID AND UPPER 20S AT 0230Z. LITTLE CHANGE NEEDED FOR THE EVENING UPDATE AS CURRENT FORECAST IN EXCELLENT SHAPE. WITH ONLY SOME THIN CIRRUS DRIFTING INTO THE REGION FROM THE WEST AFTER MIDNIGHT...MAIN FOCUS IS ON TEMPS THE REST OF THE NIGHT. DECISION TO TREND LOWS TOWARDS THE COOL END OF GUIDANCE WAS A GOOD CALL...AS MANY AREAS ARE ALREADY WITHIN A COUPLE DEGREES OF FORECAST LOWS. EXPECT LOWS TO BE REACHED AROUND OR SHORTLY AFTER 06Z WITH TEMPS STEADYING OR SLOWLY RISING THEREAFTER AS WARM ADVECTION COMMENCES AND SOUTHERLY WINDS STRENGTHEN TOWARDS DAYBREAK. UTILIZED RUC HOURLY DATA FOR TEMPERATURE INTERPOLATION OVERNIGHT WITH TEMPS RECOVERING INTO THE UPPER 20S AND LOWER 30S BY DAYBREAK. ZONE AND GRID UPDATES OUT. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... ISSUED AT 125 PM EST SAT DEC 19 2015 DRY WEATHER WILL CONTINUE TO BE EXPECTED ON SUNDAY AND SUNDAY NIGHT AS WARM AIR ADVECTION CONTINUES THROUGH THE DAY ON SOUTHWEST FLOW ALOFT. MODEL SUGGEST 850MB TEMPS REACHING NEAR 8C BY 00Z MONDAY. TIME HEIGHT SECTIONS THROUGH THE DAY SUGGEST SATURATION ALOFT...THUS WILL TREND TOWARD A PARTLY CLOUDY SKY. GIVEN THE STRONG WARM AIR ADVECTION AND SOUTHWESTERLY FLOW WILL TREND HIGHS AT OR ABOVE MAVMOS. INCREASING CLOUDS WILL BE EXPECTED ON SUNDAY NIGHT AS MODELS SUGGEST A SHORT WAVE EMBEDDED WITHIN THE SOUTHWEST FLOW ALOFT TO PUSH ACROSS THE STATE AFTER 06Z. FORECAST SOUNDINGS AND TIME TIME HEIGHTS INDICATE DEEP SATURATION. THE 300K GFS ISENTROPIC SURFACE SHOWS A SURGE OF MOISTURE WITH SPECIFIC HUMIDITIES REACHING OVER 4 G/KG ALONG WITH GOOD LIFT. THUS RAIN WILL BE EXPECTED ON SUNDAY NIGHT AFTER 06Z...AND WILL TREND POPS AT OR ABOVE GUIDANCE. GIVEN THE CLOUDS AND EXPECTED PRECIP WILL TREND LOWS WARMER THAN MAVMOS. MODELS SUGGEST THAT ON MONDAY THROUGH TUESDAY THE ASSOCIATED LOW PRESSURE SYSTEM WITH THE COLD FRONT PULLS QUICKLY TO THE NORTHEAST WHILE THE COLD FRONT STALLS AND ELONGATES ACROSS CENTRAL INDIANA AND SOUTHERN INDIANA. MEANWHILE ALOFT...MAINLY QUICK ZONAL FLOW REMAINS IN PLACE...ALLOWING A SERIES OF WEAK SHORT WAVES TO PUSH IN TO THE OHIO VALLEY THROUGH TUESDAY. GIVEN THE POOR ORGANIZATION...BUT DECENT FORCING AND A LINGERING BOUNDARY IN PLACE ACROSS THE AREA...SOME LOW CHANCE POPS WILL BE NEEDED...FOR LIGHT PRECIP EVENTS. WILL STICK CLOSE TO MAVMOS POPS THROUGH TUESDAY AND TREND LOWS WARMER THAN MAVMOS AND STICK CLOSE ON HIGHS. && .LONG TERM /TUESDAY NIGHT THROUGH NEXT SATURDAY/... ISSUED AT 216 PM EST SAT DEC 19 2015 ENSEMBLES INDICATE A MEAN UPPER RIDGE OVER THE EASTERN PARTS OF THE COUNTRY AND MEAN TROUGHING OVER THE ROCKIES DURING THIS PERIOD. PERIODIC CHANCES FOR RAIN EXPECTED AS DISTURBANCES EJECT OUT OF THE ROCKIES TROUGH. ONE UPPER WAVE WILL BE PASSING THROUGH THE LOCAL AREA AROUND WEDNESDAY OR THURSDAY MORNING. WILL CONTINUE WITH POPS THROUGH THURSDAY TO COVER THIS FEATURE. ENSEMBLES SUGGEST A DRY PERIOD FROM THURSDAY NIGHT INTO FRIDAY...BEFORE THE POTENTIAL FOR THE NEXT DISTURBANCE TO APPROACH THE AREA FRIDAY INTO NEXT SATURDAY. LARGE DIFFERENCES EXIST AMONG THE ENSEMBLE MEMBERS REGARDING THIS NEXT DISTURBANCE...WITH SOME MEMBERS KEEPING THIS SYSTEM MORE PROGRESSIVE...WHILE OTHERS CUT THIS SYSTEM OFF OVER THE SOUTHWEST. FOR NOW...WILL GO WITH CHANCE POPS FOR FRIDAY AND SATURDAY TO COVER THE MORE PROGRESSIVE SOLUTIONS. && .AVIATION /DISCUSSION FOR THE 200300Z IND TAF UPDATE/... ISSUED AT 925 PM EST SAT DEC 19 2015 CHANGED WINDS FROM 210 DEGREES TO 180 DEGREES BASED ON LATEST OB AND TRENDS. PREVIOUS DISCUSSION FOLLOWS... ISSUED AT 536 PM EST SAT DEC 19 2015 HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THE TAF PERIOD. PER MODEL RH TIME SECTIONS AND SATELLITE TRENDS...SKIES WILL BE CLEAR TONIGHT WITH CIRRUS INCREASING BY SUNDAY AFTERNOON...AS AN UPPER RIDGE PASSES THROUGH RESULTING IN SOUTHWEST FLOW ALOFT. DO NOT EXPECT FOG AS THE WINDS WILL BE VERY LIGHT FROM THE SOUTH THIS EVENING BUT INCREASE TO AROUND 6 KNOTS OVERNIGHT. THE SOUTHERLY WINDS WILL INCREASE AFTER 15Z SUNDAY TO NEAR 15 KNOTS WITH GUSTS TO 20 TO 25 KNOTS. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....JAS AVIATION...MK
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
344 PM EST FRI DEC 18 2015 .SYNOPSIS... ISSUED AT 340 PM EST FRI DEC 18 2015 AN UPPER LEVEL SYSTEM WILL RACE ACROSS THE REGION THIS EVENING WITH A CHANCE FOR LIGHT SNOW SHOWERS. LAKE EFFECT SNOW SHOWERS WILL INTENSIFY BRIEFLY OVERNIGHT ACROSS FAR NORTHERN INDIANA AND LOWER MICHIGAN WITH A FEW INCHES OF ACCUMULATION EXPECTED. WHILE IT WILL REMAIN COLD ON SATURDAY...A WARM UP IS STILL ON THE WAY FOR NEXT WEEK WITH HIGHS IN THE 40S AND 50S LEADING UP TO CHRISTMAS. LOWS TONIGHT WILL DROP INTO THE UPPER TEENS AND LOWER 20S. HIGHS ON SATURDAY WILL STILL BE IN THE LOWER 30S. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 337 PM EST FRI DEC 18 2015 AN ACTIVE SHORT TERM PERIOD WITH POTENT SHORT WAVE SLIDING THROUGH ALONG WITH LAKE EFFECT SNOW SHOWERS. ACTIVE WEATHER TO BE SHORT LIVED AS RETURN FLOW AND DRIER AIR WORK IN QUICKLY LATE TONIGHT SHUTTING DOWN PCPN. DRIER AIR AND SUBSIDENCE HAS ERODED CLOUD COVER OVER WESTERN HALF OF AREA THIS AFTERNOON WHILE FLURRIES HAVE PERSISTED EAST WITH LAKE ENHANCED SNOW SHOWERS NORTH. NEXT SHORT WAVE SEEN NICELY ON WATER VAPOR AND VIS SATELLITE IMAGES OVER SOUTHWEST WISCONSIN AND NORTHERN IOWA. THIS FEATURE WILL QUICKLY RACE EAST THIS EVENING WITH BRIEF PERIOD OF STRONG LIFT BUT SHALLOW MOISTURE. HRRR AND RAP DEVELOPING SOME LIGHT QPF NOW WITH FGEN FORCING AHEAD OF WAVE ACROSS SOUTHERN CWA. HAVE ADDED A LOW CHANCE POP FOR THIS POSSIBILITY. A FEW TENTHS OF AN INCH OF ACCUMULATION NOT OUT OF QUESTION IF PCPN CAN DEVELOP BUT SHALLOW MOISTURE...DRY LOWER LEVELS AND FAST MOVEMENT OF SYSTEM WILL BE LIMITING FACTORS. LAKE EFFECT WILL REALLY GET GOING FOR BRIEF PERIOD OVERNIGHT FOLLOWING THIS SHORT WAVE WITH QUICK INFUSION OF SYNOPTIC MOISTURE AND SEEDING/FEEDING MECHANISM. INVERSION HEIGHTS TO RISE WITH WAVE AND DGZ TO BECOME SATURATED WITH STRONG LIFT. THIS LOOKS TO ONLY LAST 3 TO 6 HOURS AS MUCH DRIER AIR AND SUBSIDENCE MOVE IN AND QUICKLY LOWER INVERSION HEIGHTS. SFC-700MB DELTA T VALUES STILL EXTREME TO 30 AND SFC-850MB TO 20C SO BRIEF INTENSE BANDS POSSIBLE. LATEST HIRES MODEL TRENDS HAVE A LITTLE MORE NORTHWESTERLY FETCH TO LOW LEVEL WINDS IN WAKE OF SHORT WAVE WHICH WILL ALSO HELP BANDS INTENSIFY WITH SLIGHTLY LONGER FETCH WHILE ALSO ALLOWING BANDS TO MAKE A BIT FURTHER PROGRESS SOUTH INTO NORTHERN INDIANA. HAVE BUMPED POPS INTO LIKELY CATEGORY OVER NORTHERN TIER OF INDIANA COUNTIES WITH CATEGORICAL POPS ACROSS MICHIGAN. ACCUMS SHOULD BE IN THE 1 TO 3 INCH RANGE WITH HIGHEST AMOUNTS ALONG CWA BORDER WITH GRR. CANNOT RULE OUT SOME ISOLATED 4 INCH AMOUNTS IF A PARTICULAR BAND REMAINS STATIONARY DURING THE OPTIMAL SHORT WINDOW. FLOW QUICKLY BACKS LATE TONIGHT AND SATURDAY WITH DRIER AIR AND CLEARING WORKING IN FROM SOUTHWEST TO NORTHEAST AND SHUTTING DOWN LAKE EFFECT. STILL COLD FOR THIS WINTER WITH HIGHS AROUND 30 TO LOWER 30S. && .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 337 PM EST FRI DEC 18 2015 A RELATIVELY QUIET LONG TERM PERIOD...FROM AN IMPACTS PERSPECTIVE. LONGWAVE RIDGE WILL FOLD OVER THE GREAT LAKES EARLY NEXT WEEK AND SET UP OVER THE NORTHWEST ATLANTIC...KEEPING OUR AREA IN GENERAL SW FLOW THROUGH MUCH OF NEXT WEEK. HIGHS WILL CLIMB BACK ABOVE NORMAL AND REMAIN THERE THROUGH CHRISTMAS. TWO SHORTWAVES WILL BRING A CHANCE OF RAIN NEXT WEEK. THE FIRST WILL ARRIVE LATE SUNDAY INTO MONDAY. DYNAMICS OF THE WAVE NOT IMPRESSIVE AT ALL BUT WILL SEE A PRETTY GOOD MOISTURE SURGE IN DEEP/STRONG SW FLOW. THIS SHOULD BE ENOUGH FOR NUM LIGHT SHOWERS ALONG TRAILING CONVERGENT BOUNDARY. SECOND (DEEPER) WAVE WILL APPROACH THE REGION ON WEDNESDAY. BETTER HEIGHT FALLS/CVA AND ASSOCIATED MOISTURE TRANSPORT LIKELY TO BRING A BETTER CHANCE FOR RAIN BUT MODELS STILL STRUGGLING WITH EXACT TIMING AND EVOLUTION. CONTINUED WITH FAIRLY BROADBRUSHED CHANCE POPS. DO GET SOME SLIGHTLY COOLER AIR BY CHRISTMAS DAY BUT CHANCES FOR WHITE CHRISTMAS APPEAR VERY LOW AT THIS POINT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1228 PM EST FRI DEC 18 2015 SUBSIDENCE AND DRIER AIR HELPING TO BRIEFLY CLEAR SKIES WEST OF TAF SITES. FINALLY STARTING TO SEE SOME ADDITIONAL CLOUD DEVELOPMENT ON WESTERN PERIPHERY. EXPECT KSBN TO REMAIN BROKEN WITH INFLUENCE FROM LAKE IN WESTERLY FLOW ALOFT BUT CIGS LOOK TO BE VFR THROUGH AFTERNOON. PARTIAL CLEARING AT KFWA WITH VFR AS WELL. NEXT POTENT SHORT WAVE DROPS IN THIS EVENING WITH INCREASING CLOUDS AND MVFR CIGS PER LATEST HIRES GUIDANCE. THIS SHOULD INVIGORATE LAKE EFFECT WITH TRAJECTORIES ALLOWING SOME SNOW SHOWERS AND VIS RESTRICTIONS INTO KSBN. FLURRIES OR LIGHT SNOW SHOWERS POSSIBLE AT KFWA AS HRRR AND RAP INDICATE SOME LIGHT PCPN BREAKING OUT. FOR NOW KEPT VIS IN P6SM CATEGORY BUT WILL HAVE TO MONITOR DEVELOPMENT. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST SATURDAY FOR LMZ043-046. && $$ SYNOPSIS...STEINWEDEL SHORT TERM...LASHLEY LONG TERM...AGD AVIATION...LASHLEY VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1235 PM EST FRI DEC 18 2015 .SYNOPSIS... ISSUED AT 1102 AM EST FRI DEC 18 2015 COLDER CONDITIONS MORE TYPICAL OF DECEMBER WILL PERSIST TODAY INTO SATURDAY WITH HIGHS GENERALLY IN THE LOW 30S EACH DAY. LAKE EFFECT SNOW SHOWERS AND FLURRIES WILL ALSO BE POSSIBLE TODAY INTO TONIGHT...ESPECIALLY NORTH OF THE INDIANA TOLL ROAD WHERE LIGHT ACCUMULATIONS MAY OCCUR BY LATER THIS AFTERNOON AND EVENING. MILDER WEATHER WILL SPREAD BACK INTO THE REGION SUNDAY INTO EARLY NEXT WEEK...WITH RAIN CHANCES RETURNING SUNDAY NIGHT INTO MONDAY. && .UPDATE... ISSUED AT 1100 AM EST FRI DEC 18 2015 FLURRIES AND LIGHT SNOW SHOWERS DEVELOPING LATE THIS MORNING WITH SUBTLE SHORT WAVE AND COLD AIR ADVECTION. NARROW ENHANCED BAND FROM MICHIGAN CITY TO SOUTH BEND DROPPING VIS TO AROUND 2 MILES. SATELLITE SHOWING CLEARING AND DRIER AIR JUST UPSTREAM IN SUBSIDENCE BEHIND THIS WAVE ON NOSE OF LOW LEVEL RIDGING. EXPECT THESE SNOW SHOWERS TO DIMINISH BY EARLY AFTERNOON OVER NORTHWEST INDIANA AND TRANSLATE MORE INTO MICHIGAN. VIS SATELLITE ALSO NOT SHOWING MUCH CU DEVELOPMENT YET TO OUR WEST WITHIN COLDER AIR. MAY NEED ANOTHER UPDATE SHORTLY FOR PARTIAL CLEARING UNTIL NEXT SHORT WAVE DROPS INTO AREA MID TO LATE AFTERNOON. WILL CONTINUE TO MONITOR. STILL LOOKS TO BE WINDOW OF DECENT LAKE EFFECT FROM 00Z TO 09Z TONIGHT ACROSS MAINLY MICHIGAN COUNTIES. LOOKING AT POSSIBILITY OF BUMPING AMOUNTS JUST A BIT OVER THE EXTREME NORTH WITH LOCAL ACCUMS UP TO 3 INCHES POSSIBLE WITH NARROW BAND. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 317 AM EST FRI DEC 18 2015 SEASONABLY COLD WITH CHANCES FOR SNOW SHOWERS THE HIGHLIGHTS TODAY INTO TONIGHT... PRIMARY MID-UPPER LEVEL TROUGH AXIS/COLD POOL WILL TRANSLATE EAST THROUGH THE LOCAL AREA TODAY. RESULTING DEEPENING OF MIXED LAYER/STEEPENING LAPSE RATES SHOULD PROMOTE A SOMEWHAT BREEZY LATE MORNING/AFTERNOON...WITH POSSIBLY ENOUGH LINGERING BOUNDARY LAYER MOISTURE TO FORCE SCATTERED FLURRIES. MUCH BETTER CHANCES FOR MORE SUBSTANTIAL SNOW SHOWER ACTIVITY ACROSS SW LOWER MI AS LAKE INDUCED INSTABILITY RAMPS UP IN RESPONSE TO 30C LAKE-700 MB TEMP DIFFERENTIALS. HOWEVER...GUSTY/SHEARED WESTERLY FETCH AND DRY UPSTREAM AIRMASS SHOULD HAMPER ORGANIZATION/COVERAGE WITH LITTLE ACCUMULATION/IMPACTS ANTICIPATED TODAY. THIS LIKELY CHANGES SOMEWHAT FOR AREAS MAINLY ALONG/NORTH OF THE INDIANA TOLL ROAD THIS EVENING INTO THE EARLY OVERNIGHT AS A TRAILING/COMPACT UPPER WAVE DROPS THROUGH IN WNW FLOW. ASSOCIATED DEEPER MOISTURE WELL INTO THE DGZ AND HINTS OF A LOW LEVEL FGEN RESPONSE MAY PROVIDE ENOUGH ADDITIONAL ENHANCEMENT FOR A MORE FOCUSED CONVERGENT BAND DURING THIS TIME ACROSS THE FAR NORTH. COULD SEE A QUICK 1-2 INCHES OF SNOW ACCUMULATION AND A FEW SLICK SPOTS WHERE THIS BETTER BANDING SETS UP. FLURRIES POSSIBLE ELSEWHERE WITH TEMPS SLIGHTLY BELOW NORMAL. && .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 317 AM EST FRI DEC 18 2015 MILD AND POTENTIALLY VERY WET IS THE UNDERLYING THEME THIS PD W/MODEL BASED UNCERTAINTY SUBSTANTIALLY LESS W/POTENT MID WEEK SYS COMPARED TO YDA. TO START...ONE MORE SEASONABLY COLD DAY XPCD ON SAT AS SFC RIDGE WORKS ACRS THE AREA FOLLOWED BY RAPID ONSET OF STG LL WAA ON SUN. THIS WILL PROPEL TEMPS WELL ABV NORMAL LASTING THROUGHOUT THE END OF THE PD AS NEG PNA PATTN MANIFESTS ACRS NOAM IN RESPONSE TO INCOMING ENERGETIC PAC WAVE TRAIN. FIRST IN SERIES OF DISTURBANCES TO TURN THROUGH THE SRN ROCKIES SUN AND THEN MINOR OUT THROUGH THE LAKES ON MON. WHILE ACCOMPANYING DYNAMICS ALG SWD TRAILING FNTL ZONE NOT ALL THAT IMPRESSIVE...NWD EXTENT OF GOMEX BASED MSTR RTN SHLD YIELD ANOTHER WIDESPREAD BUT LIGHT RAIN EVENT FM LT SUN NIGHT THROUGH MON AM. MUCH MORE SIG SYS XPCD TO DVLP WWD ACRS THE CNTRL PLAINS TUE W/FAR GREATER DOWNSTREAM MSTR TAP XPCD TO EVOLVE THROUGH THE OH VALLEY/GREAT LAKES ESP ON WED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1228 PM EST FRI DEC 18 2015 SUBSIDENCE AND DRIER AIR HELPING TO BRIEFLY CLEAR SKIES WEST OF TAF SITES. FINALLY STARTING TO SEE SOME ADDITIONAL CLOUD DEVELOPMENT ON WESTERN PERIPHERY. EXPECT KSBN TO REMAIN BROKEN WITH INFLUENCE FROM LAKE IN WESTERLY FLOW ALOFT BUT CIGS LOOK TO BE VFR THROUGH AFTERNOON. PARTIAL CLEARING AT KFWA WITH VFR AS WELL. NEXT POTENT SHORT WAVE DROPS IN THIS EVENING WITH INCREASING CLOUDS AND MVFR CIGS PER LATEST HIRES GUIDANCE. THIS SHOULD INVIGORATE LAKE EFFECT WITH TRAJECTORIES ALLOWING SOME SNOW SHOWERS AND VIS RESTRICTIONS INTO KSBN. FLURRIES OR LIGHT SNOW SHOWERS POSSIBLE AT KFWA AS HRRR AND RAP INDICATE SOME LIGHT PCPN BREAKING OUT. FOR NOW KEPT VIS IN P6SM CATEGORY BUT WILL HAVE TO MONITOR DEVELOPMENT. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST SATURDAY FOR LMZ043-046. && $$ UPDATE...LASHLEY SYNOPSIS...STEINWEDEL SHORT TERM...STEINWEDEL LONG TERM...T AVIATION...LASHLEY VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
FOR THIS EXTENDED FORECAST DISCUSSION...OVERALL QUIET AND WARM
WEATHER SHOULD BE ANTICIPATED. IF THERE IS ANY HOPE OF A WHITE
CHRISTMAS...IT WOULD BE FROM THE SNOW MIRACULOUSLY NOT MELTING DURING THE WARM DAYS BETWEEN NOW AND FRIDAY. THAT BEING SAID...A LARGE UPPER LEVEL DISTURBANCE MAY BEGIN TO HAVE AN IMPACT ON THE WEATHER AS SOON AS THE END OF NEXT WEEK. THIS SYSTEM BEARS WATCHING. BEGINNING WITH SATURDAY NIGHT THROUGH TUESDAY...ANTICIPATING GENERALLY WARMER THAN NORMAL TEMPERATURES AND DRY WEATHER. THIS IS DUE TO A RIDGE OF HIGH PRESSURE INITIALLY OVER THE HIGH PLAINS. A WEAK SHORTWAVE TROUGH BREAKS THE RIDGE DOWN AND FORCES A WEAK COLD FRONT THROUGH SUNDAY. A BRIEF COOLING IS FORECAST SUNDAY AND MONDAY. A RETURN TO WARM AIR ADVECTION IS EXPECTED TUESDAY AND FORECAST WARMER TEMPERATURES. A FEW PIECES OF GUIDANCE ARE INDICATING SOME VERY LIGHT PRECIPITATION AS THE DISTURBANCE PASSES THROUGH SUNDAY NIGHT. HOWEVER...A LAYER OF DRY AIR ALOFT LIKELY PREVENTS PRECIPITATION FROM REACHING THE GROUND. THEREFORE...WENT WITH A DRY FORECAST. TUESDAY NIGHT INTO WEDNESDAY...ANOTHER UPPER LEVEL DISTURBANCE AND COLD FRONT WILL BRING ANOTHER BRIEF COOL SPELL. IN ADDITION...THERE MAY BE A SMALL CHANCE FOR PRECIPITATION AS THE SYSTEM PASSES EARLY WEDNESDAY MORNING. ONCE AGAIN...A LAYER OF DRY AIR ALOFT SHOULD REDUCE PRECIPITATION CHANCES SO WOULD NOT EXPECT ANYTHING SIGNIFICANT. CENTRAL REGION INITIALIZATION LOWERED POPS AND DECIDED TO LOWER THEM FURTHER. INSTEAD OF MENTIONING A SLIGHT CHANCE FOR SNOW...DECIDED A SCATTERED FLURRIES MENTION WAS MORE APPROPRIATE GIVEN THE DRY AIR ALOFT. IN THE WAKE OF THIS DISTURBANCE...A RIDGE OF HIGH PRESSURE BUILDS AGAIN OVER THE SOUTHWESTERN UNITED STATES. THIS RIDGE SHOULD SLIDE EAST BY NEXT WEEKEND AS A LARGE UPPER LEVEL TROUGH DIGS SOUTH OVER THE WESTERN UNITED STATES. THIS WOULD LEAD TO A SIGNIFICANT WARMUP IN TIME FOR CHRISTMAS EVE AND CHRISTMAS DAY. GUIDANCE CONTINUES TO TREND WARMER AS CONFIDENCE INCREASES IN THIS UPPER LEVEL PATTERN. IN THE END...THINKING CHRISTMAS EVE AND CHRISTMAS DAY SHOULD BE WARMER THAN NORMAL (NORMAL GOODLAND HIGH: 42, NORMAL GOODLAND LOW: 17). && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 900 PM MST FRI DEC 18 2015 FOR KGLD AND KMCK...VFR THROUGH THE PERIOD. WINDS AT KGLD GENERALLY FROM THE SOUTHWEST UNDER 10KTS THROUGH 16Z BEFORE BACKING A BIT AND GETTING A FEW GUSTS OF 15-20KTS FROM 17Z-21Z. AFTER 05Z WINDS VEER BACK TO THE SOUTHWEST AGAIN NEAR 10KTS. FOR KMCK WINDS LIGHT AND VARIABLE FROM TAF ISSUANCE THROUGH 18Z BEFORE BECOMING SOUTHEASTERLY AROUND 7KTS FROM 19Z-04Z. AFTER 05Z WINDS BECOME LIGHT AND VARIABLE AGAIN. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...CLT LONG TERM...RRH AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
151 AM MST FRI DEC 18 2015 .UPDATE... ISSUED AT 1010 PM MST THU DEC 17 2015 PER COORDINATION WITH DODGE CITY OFFICE HAVE ADDED SOME PATCHY FREEZING FOG TO GREELEY AND WICHITA COUNTIES FROM 10Z-15Z THURSDAY. NAM/GFS/RUC ALL TO ONE EXTENT OR ANOTHER HAVE SATURATED/NEAR SATURATED BOUNDARY LAYER MOISTURE IN THIS AREA WITH REDUCED VISIBILITIES IN FREEZING FOG. THIS MATCHES BRIEFING FROM DAY SHIFT AND GIVEN THE LATEST GUIDANCE WENT AHEAD AND INTRODUCED IT. MIDNIGHT SHIFT CAN TAKE A LOOK AT REAL TIME DATA AND SHORT TERM MODEL GUIDANCE AND ADJUST AS NEEDED. IF THE HRRR VISIBILITY FORECAST VERIFIES DENSE FREEZING FOG WOULD DEVELOP. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 209 PM MST THU DEC 17 2015 THE SHORTWAVE TROUGH THAT HAS BEEN MOVING OVER THE CWA TODAY WILL BE SOUTHEAST OF THE REGION BY 00Z TONIGHT...THIS ALONG WITH DRY AIR BEING ADVECTED INTO THE REGION WILL END THE LIGHT SNOWFALL AND FLURRIES OVER THE AREA. SATELLITE VISIBILITY SHOWS CLOUD COVER OVER THE REGION IN ASSOCIATION WITH THE SHORTWAVE AND SNOWFALL BUT WILL START TO CLEAR OUT FROM THE NORTHWEST TO SOUTHEAST AROUND 22Z THURSDAY. SKIES WILL BE MOSTLY CLEAR WITH LIGHT WINDS OVERNIGHT ...THIS WILL DROP THE TEMPERATURES TO NEARLY ZERO DEGREES F UP TO THE MID TEENS. THE CURRENT MODEL RUNS AND FORECAST HAVE NO FOG EXPECTED TO DEVELOP OVER THE CWA...BUT THE SREF HAS SOME REDUCED VISIBILITIES OF LESS THAN 3 MILES FRIDAY MORNING IN SOUTHWEST KANSAS...THE HRRR ALSO SHOWS SOMETHING DEVELOPING OVER THE SAME AREA...BUT CONFIDENCE IS LOW THAT FOG WILL MAKE IT UP INTO OUR AREA DUE TO THE 10 KTS SOUTHWEST WINDS. WILL HAVE TO KEEP AN EYE OUT ON THIS...IF THERE IS ANY FOG TO DEVELOP IT WILL BE IN THE SOUTHERN CWA COUNTIES. A RIDGE WILL START TO PUSH INTO THE CWA THURSDAY EVENING INTO FRIDAY...BRING WITH IT DRY CONDITIONS AND WINDS FROM THE SOUTHWEST...THIS WILL FAVOR MUCH WARMER TEMPERATURES IN THE MID 40S TO LOW 50S. .LONG TERM...(MONDAY THROUGH THURSDAY) ISSUED AT 147 AM MST FRI DEC 18 2015 FORECAST PROBLEM CONTINUES TO BE A LOW CHANCE OF PRECIPITATION IN THE MIDDLE OF NEXT WEEK. SATELLITE CURRENTLY SHOWING AN AMPLIFIED PATTERN FROM THE CENTRAL PACIFIC INTO THE CENTRAL ATLANTIC. MODELS HAVE NOT CHANGED TOO MUCH FROM YESTERDAY. THEY ARE STILL SHOWING A PROGRESSIVE FLOW WITH SEVERAL OPEN WAVES MOVING THROUGH A WEST TO NORTHWEST FLOW ALOFT. THINGS ARE LOOKING A LITTLE MORE INTERESTING ON WEDNESDAY AND WEDNESDAY NIGHT. AT THAT TIME A LEFT FRONT QUADRANT OF A STRONG JET LOOKS TO AFFECT THE AREA...MAINLY THE SOUTHWEST PORTION. ONE OF THE WAVES MENTIONED ABOVE MOVES THROUGH IN NORTHWEST FLOW ALOFT. MODELS ARE SHOWING A DECENT BAROCLINIC ZONE NEAR 700 MB WHEN ALL THE MID AND UPPER LIFT MOVES THROUGH. SHORTWAVE WILL ALSO FORCE A COLD FRONT THROUGH AT THE SAME TIME. MODEL SOUNDINGS WOULD INDICATE THE AIR MASS SATURATED DOWN TO JUST BELOW 700 MB. SO BASED ON ALL THAT... COLLABORATION...AND THIS BEING TWO DAYS BEFORE CHRISTMAS... DECIDED TO LEAVE THE SLIGHT CHANCE POPS FOR WEDNESDAY AND WEDNESDAY NIGHT...IN THE SOUTHWEST PORTION OF THE AREA...THAT THE CRH_INIT GAVE ME. THIS SETUP LOOKS ABOUT THE SAME TO A LITTLE BETTER THAN WHAT GAVE US THE LIGHT SNOW YESTERDAY. OVERALL DID NOT SEE ANY STRONG REASON TO CHANGE ANY PARAMETER THAT THE INIT GAVE ME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 945 PM MST THU DEC 17 2015 FOR KGLD AND KMCK...VFR THROUGH THE PERIOD. WINDS GENERALLY FROM THE WEST AND WEST-SOUTHWEST UNDER 10KTS FROM TAF ISSUANCE THROUGH THE REST OF THE PERIOD. KGLD MAY FLIRT WITH 12KT THRESHOLD FOR THE FIRST 6 HOURS OR SO. ONLY SOME FAIR WEATHER CU AND CIRRUS EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...99 SHORT TERM...CLT LONG TERM...BULLER AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1010 PM MST THU DEC 17 2015 .UPDATE... ISSUED AT 1010 PM MST THU DEC 17 2015 PER COORDINATION WITH DODGE CITY OFFICE HAVE ADDED SOME PATCHY FREEZING FOG TO GREELEY AND WICHITA COUNTIES FROM 10Z-15Z THURSDAY. NAM/GFS/RUC ALL TO ONE EXTENT OR ANOTHER HAVE SATURATED/NEAR SATURATED BOUNDARY LAYER MOISTURE IN THIS AREA WITH REDUCED VISIBILITIES IN FREEZING FOG. THIS MATCHES BRIEFING FROM DAY SHIFT AND GIVEN THE LATEST GUIDANCE WENT AHEAD AND INTRODUCED IT. MIDNIGHT SHIFT CAN TAKE A LOOK AT REAL TIME DATA AND SHORT TERM MODEL GUIDANCE AND ADJUST AS NEEDED. IF THE HRRR VISIBILITY FORECAST VERIFIES DENSE FREEZING FOG WOULD DEVELOP. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 209 PM MST THU DEC 17 2015 THE SHORTWAVE TROUGH THAT HAS BEEN MOVING OVER THE CWA TODAY WILL BE SOUTHEAST OF THE REGION BY 00Z TONIGHT...THIS ALONG WITH DRY AIR BEING ADVECTED INTO THE REGION WILL END THE LIGHT SNOWFALL AND FLURRIES OVER THE AREA. SATELLITE VISIBILITY SHOWS CLOUD COVER OVER THE REGION IN ASSOCIATION WITH THE SHORTWAVE AND SNOWFALL BUT WILL START TO CLEAR OUT FROM THE NORTHWEST TO SOUTHEAST AROUND 22Z THURSDAY. SKIES WILL BE MOSTLY CLEAR WITH LIGHT WINDS OVERNIGHT ...THIS WILL DROP THE TEMPERATURES TO NEARLY ZERO DEGREES F UP TO THE MID TEENS. THE CURRENT MODEL RUNS AND FORECAST HAVE NO FOG EXPECTED TO DEVELOP OVER THE CWA...BUT THE SREF HAS SOME REDUCED VISIBILITIES OF LESS THAN 3 MILES FRIDAY MORNING IN SOUTHWEST KANSAS...THE HRRR ALSO SHOWS SOMETHING DEVELOPING OVER THE SAME AREA...BUT CONFIDENCE IS LOW THAT FOG WILL MAKE IT UP INTO OUR AREA DUE TO THE 10 KTS SOUTHWEST WINDS. WILL HAVE TO KEEP AN EYE OUT ON THIS...IF THERE IS ANY FOG TO DEVELOP IT WILL BE IN THE SOUTHERN CWA COUNTIES. A RIDGE WILL START TO PUSH INTO THE CWA THURSDAY EVENING INTO FRIDAY...BRING WITH IT DRY CONDITIONS AND WINDS FROM THE SOUTHWEST...THIS WILL FAVOR MUCH WARMER TEMPERATURES IN THE MID 40S TO LOW 50S. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 209 PM MST THU DEC 17 2015 A RIDGE WILL MOVE INTO THE PLAINS FRIDAY NIGHT AND SATURDAY. THE RIDGE WILL SHIFT EAST SATURDAY NIGHT AHEAD OF A TROUGH THAT IS PROGGED TO SHIFT EAST INTO CENTRAL COLORADO SUNDAY. SURFACE HIGH PRESSURE WILL CONTINUE OVER THE PLAINS FRIDAY NIGHT. A TROUGH WILL MOVE INTO EASTERN COLORADO SATURDAY AND THEN SHIFT EAST INTO NORTHWEST KANSAS SUNDAY. SUBSIDENCE WILL CONTINUE THROUGH SATURDAY. LACK OF SUFFICIENT MOISTURE WILL PERSIST THROUGH SATURDAY NIGHT AND SUNDAY AS DYNAMICS FROM A SHORTWAVE TROUGH START TO MOVE INTO THE AREA. AS A RESULT, DRY CONDITIONS SHOULD CONTINUE THROUGH SUNDAY. POPS WILL BE NIL FOR THESE PERIODS. MIN TEMPERATURES SHOULD COOL TO THE LOWER 20S FRIDAY NIGHT AND THEN MODERATE TO THE MID AND UPPER 20S SATURDAY NIGHT. MAX TEMPERATURES FRIDAY SHOULD REACH THE MID 50S BUT COOLER READINGS ARE EXPECTED SUNDAY IN THE MID TO UPPER 40S. IN THE EXTENDED...(SUNDAY NIGHT THROUGH THURSDAY)... UPPER FLOW WILL BE NORTHWEST SUNDAY NIGHT AND THEN BECOME ZONAL MONDAY. A TROUGH WILL MOVE THROUGH THE PLAINS TUESDAY AND WEDNESDAY. NORTHWEST FLOW WILL RESUME THURSDAY BEHIND THE EXITING TROUGH. SURFACE HIGH PRESSURE WILL MOVE INTO THE AREA SUNDAY NIGHT AND THEN SHIFT EAST MONDAY AS A TROUGH MOVES INTO EASTERN COLORADO. THE TROUGH WILL REMAIN OVER THE AREA THROUGH TUESDAY AND THEN SHIFT SOUTH WEDNESDAY AHEAD OF A COLD FRONT MOVING INTO THE AREA. HIGH PRESSURE WILL BUILD INTO NORTHWEST KANSAS THURSDAY BEHIND THE EXITING TROUGH. THE EXTENDED FORECAST WILL REMAIN DRY DUE TO SUBSIDENCE SUNDAY NIGHT AND MONDAY. MODEL DIFFERENCES DUE TO TIMING AND/OR AVAILABLE MOISTURE FOR TUESDAY THROUGH THURSDAY RESULT IN A DRY FORECAST FOR THOSE PERIODS AS WELL. MIN TEMPERATURES ARE EXPECTED IN THE LOWER TO MIDDLE 20S WITH SOME UPPER 20S POSSIBLE IN THE FAR EAST TUESDAY NIGHT. MAX TEMPERATURES SHOULD REACH THE MID AND UPPER 40S MOST DAYS WITH THE EXCEPTIONS OF MONDAY AND THURSDAY WHEN SLIGHTLY COOLER TEMPERATURES ARE EXPECTED. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 945 PM MST THU DEC 17 2015 FOR KGLD AND KMCK...VFR THROUGH THE PERIOD. WINDS GENERALLY FROM THE WEST AND WEST-SOUTHWEST UNDER 10KTS FROM TAF ISSUANCE THROUGH THE REST OF THE PERIOD. KGLD MAY FLIRT WITH 12KT THRESHOLD FOR THE FIRST 6 HOURS OR SO. ONLY SOME FAIR WEATHER CU AND CIRRUS EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...99 SHORT TERM...CLT LONG TERM...FS AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
945 PM MST THU DEC 17 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 209 PM MST THU DEC 17 2015 THE SHORTWAVE TROUGH THAT HAS BEEN MOVING OVER THE CWA TODAY WILL BE SOUTHEAST OF THE REGION BY 00Z TONIGHT...THIS ALONG WITH DRY AIR BEING ADVECTED INTO THE REGION WILL END THE LIGHT SNOWFALL AND FLURRIES OVER THE AREA. SATELLITE VISIBILITY SHOWS CLOUD COVER OVER THE REGION IN ASSOCIATION WITH THE SHORTWAVE AND SNOWFALL BUT WILL START TO CLEAR OUT FROM THE NORTHWEST TO SOUTHEAST AROUND 22Z THURSDAY. SKIES WILL BE MOSTLY CLEAR WITH LIGHT WINDS OVERNIGHT ...THIS WILL DROP THE TEMPERATURES TO NEARLY ZERO DEGREES F UP TO THE MID TEENS. THE CURRENT MODEL RUNS AND FORECAST HAVE NO FOG EXPECTED TO DEVELOP OVER THE CWA...BUT THE SREF HAS SOME REDUCED VISIBILITIES OF LESS THAN 3 MILES FRIDAY MORNING IN SOUTHWEST KANSAS...THE HRRR ALSO SHOWS SOMETHING DEVELOPING OVER THE SAME AREA...BUT CONFIDENCE IS LOW THAT FOG WILL MAKE IT UP INTO OUR AREA DUE TO THE 10 KTS SOUTHWEST WINDS. WILL HAVE TO KEEP AN EYE OUT ON THIS...IF THERE IS ANY FOG TO DEVELOP IT WILL BE IN THE SOUTHERN CWA COUNTIES. A RIDGE WILL START TO PUSH INTO THE CWA THURSDAY EVENING INTO FRIDAY...BRING WITH IT DRY CONDITIONS AND WINDS FROM THE SOUTHWEST...THIS WILL FAVOR MUCH WARMER TEMPERATURES IN THE MID 40S TO LOW 50S. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 209 PM MST THU DEC 17 2015 A RIDGE WILL MOVE INTO THE PLAINS FRIDAY NIGHT AND SATURDAY. THE RIDGE WILL SHIFT EAST SATURDAY NIGHT AHEAD OF A TROUGH THAT IS PROGGED TO SHIFT EAST INTO CENTRAL COLORADO SUNDAY. SURFACE HIGH PRESSURE WILL CONTINUE OVER THE PLAINS FRIDAY NIGHT. A TROUGH WILL MOVE INTO EASTERN COLORADO SATURDAY AND THEN SHIFT EAST INTO NORTHWEST KANSAS SUNDAY. SUBSIDENCE WILL CONTINUE THROUGH SATURDAY. LACK OF SUFFICIENT MOISTURE WILL PERSIST THROUGH SATURDAY NIGHT AND SUNDAY AS DYNAMICS FROM A SHORTWAVE TROUGH START TO MOVE INTO THE AREA. AS A RESULT, DRY CONDITIONS SHOULD CONTINUE THROUGH SUNDAY. POPS WILL BE NIL FOR THESE PERIODS. MIN TEMPERATURES SHOULD COOL TO THE LOWER 20S FRIDAY NIGHT AND THEN MODERATE TO THE MID AND UPPER 20S SATURDAY NIGHT. MAX TEMPERATURES FRIDAY SHOULD REACH THE MID 50S BUT COOLER READINGS ARE EXPECTED SUNDAY IN THE MID TO UPPER 40S. IN THE EXTENDED...(SUNDAY NIGHT THROUGH THURSDAY)... UPPER FLOW WILL BE NORTHWEST SUNDAY NIGHT AND THEN BECOME ZONAL MONDAY. A TROUGH WILL MOVE THROUGH THE PLAINS TUESDAY AND WEDNESDAY. NORTHWEST FLOW WILL RESUME THURSDAY BEHIND THE EXITING TROUGH. SURFACE HIGH PRESSURE WILL MOVE INTO THE AREA SUNDAY NIGHT AND THEN SHIFT EAST MONDAY AS A TROUGH MOVES INTO EASTERN COLORADO. THE TROUGH WILL REMAIN OVER THE AREA THROUGH TUESDAY AND THEN SHIFT SOUTH WEDNESDAY AHEAD OF A COLD FRONT MOVING INTO THE AREA. HIGH PRESSURE WILL BUILD INTO NORTHWEST KANSAS THURSDAY BEHIND THE EXITING TROUGH. THE EXTENDED FORECAST WILL REMAIN DRY DUE TO SUBSIDENCE SUNDAY NIGHT AND MONDAY. MODEL DIFFERENCES DUE TO TIMING AND/OR AVAILABLE MOISTURE FOR TUESDAY THROUGH THURSDAY RESULT IN A DRY FORECAST FOR THOSE PERIODS AS WELL. MIN TEMPERATURES ARE EXPECTED IN THE LOWER TO MIDDLE 20S WITH SOME UPPER 20S POSSIBLE IN THE FAR EAST TUESDAY NIGHT. MAX TEMPERATURES SHOULD REACH THE MID AND UPPER 40S MOST DAYS WITH THE EXCEPTIONS OF MONDAY AND THURSDAY WHEN SLIGHTLY COOLER TEMPERATURES ARE EXPECTED. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 945 PM MST THU DEC 17 2015 FOR KGLD AND KMCK...VFR THROUGH THE PERIOD. WINDS GENERALLY FROM THE WEST AND WEST-SOUTHWEST UNDER 10KTS FROM TAF ISSUANCE THROUGH THE REST OF THE PERIOD. KGLD MAY FLIRT WITH 12KT THRESHOLD FOR THE FIRST 6 HOURS OR SO. ONLY SOME FAIR WEATHER CU AND CIRRUS EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...CLT LONG TERM...FS AVIATION...99
AREA FORECAST DISCUSSION
NWS JACKSON KY
305 PM EST FRI DEC 18 2015 .UPDATE... ISSUED AT 1145 AM EST FRI DEC 18 2015 SEVERAL REPORTS OF FLURRIES HAVE BEEN RECEIVED FROM ACROSS THE REGION THIS MORNING. RADAR TRENDS AND RECENT HRRR RUNS INDICATE THAT THE FLURRIES SHOULD OCCUR ON AND OFF FOR MOST OF THE DAY...AND LINGER INTO THE EVENING ACROSS THE SOUTHEAST. WITH PEAK HEATING AN ISOLATED SNOW SHOWER OR TWO WILL BE POSSIBLE...MAINLY ACROSS THE SOUTHEAST. WITH COLD AIR ADVECTION OCCURRING...TEMPERATURE SHOULD RISE VERY LITTLE TODAY. HOURLY GRIDS HAVE BEEN ADJUSTED BASED ON RECENT OBSERVATIONS. UPDATE ISSUED AT 810 AM EST FRI DEC 18 2015 SOME REPORTS OF FLURRIES HAVE BEEN RECEIVED AT THE OFFICE SO FAR EARLY THIS MORNING SO THE FORECAST IS ON TRACK WITH THAT RESPECT. OTHERWISE...HAVE ADJUSTED THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM EST FRI DEC 18 2015 07Z SFC ANALYSIS SHOWS HIGH PRESSURE EASING INTO THE STATE FROM THE WEST WHILE LOW PRESSURE IS NOT FAR OFF TO THE SOUTHEAST WITH ITS CYCLONIC FLOW STILL IMPACTING FAR EAST KENTUCKY. AS SUCH...LOW CLOUDS HAVE REDEVELOPED IN THE EAST AND PRESSED IN FROM THE NORTHWEST WHILE CAA CONTINUES ON LIGHT WEST TO NORTHWEST WINDS. ACCORDINGLY...TEMPERATURES ARE RATHER UNIFORM ACROSS THE AREA GENERALLY IN THE UPPER 20S AND LOWER 30S. DEWPOINTS ARE NOT FAR FROM DRY BULB VALUES AND THIS COULD LEAD TO SOME PATCHY FOG NEAR BODIES OF WATER TOWARD DAWN. FINALLY...THE LOWER CLOUDS COULD ALSO BE DROPPING A FEW VERY LIGHT SNOW SHOWERS OR FLURRIES...THOUGH THE LOCAL RADARS ARE SHOWING NO RETURNS AT THE MOMENT. THE MODELS ARE IN EXCELLENT AGREEMENT IN THE SHORT TERM AS THEY ALL DEPICT A LARGE TROUGH ROLLING THROUGH THE GREAT LAKES WHILE BOTTOMING OUT OVER KENTUCKY EARLY THIS MORNING. AS THE AXIS OF THIS 5H TROUGH PASSES PLENTY OF SHORTWAVE ENERGY WILL ACCOMPANY IT CROSSING OVER EASTERN KENTUCKY THROUGH 00Z SATURDAY. IN THE WAKE OF THE TROUGH...HEIGHTS WILL SLOWLY CLIMB ABOVE KENTUCKY FOR SATURDAY WITH ANY SIGNIFICANT ENERGY STAYING OFF TO THE NORTHEAST OF THE CWA. GIVEN THE MODEL AGREEMENT HAVE FAVORED THE HIGHER RESOLUTION GUIDANCE FROM THE HRRR AND NAM12 FOR THE SHORT TERM PORTION OF THE FORECAST. SENSIBLE WEATHER WILL FEATURE A CHILLY START THROUGH EAST KENTUCKY UNDER THE INCREASING INFLUENCE OF HIGH PRESSURE WHILE LOW CLOUDS PROVIDE A SMALL CHANCE FOR SOME SNOWFLAKES IN THE AIR...MAINLY IN THE FORM OF FLURRIES. A COMPONENT OF UPSLOPE FLOW SHOULD BE ABLE TO ACTIVATE THE LINGERING LOW LEVEL MOISTURE FOR SHOW SHOWERS IN THE HIGHER TERRAIN NEAR THE VIRGINIA BORDER LATER THIS MORNING. IN THESE LOCATIONS CANNOT RULE OUT A DUSTING OF SNOW THAT WILL ALMOST CERTAINLY MELT ON CONTACT WITH THE STILL WARM ROAD SURFACES AND GROUND. THE THREAT FOR LIGHT PCPN WANES FROM WEST TO EAST LATER TODAY WITH THE LOW CLOUDS LIFTING AND BREAKING UP BY EVENING. THE LOSS OF MOST OF THE CLOUDS WILL SET THE STAGE FOR ANOTHER CHILLY NIGHT THROUGHOUT THE CWA WITH A SMALL RIDGE TO VALLEY TEMPERATURE SPLIT LIKELY. SATURDAY WILL BE SEASONABLY COOL DESPITE NEAR FULL SUNSHINE AS THE HIGH MOVES RIGHT OVER HEAD. OF NOTE...THESE NEXT TWO DAYS MAY END UP BEING THE COLDEST OF DECEMBER GIVEN THE SHAPE OF THE UPCOMING FORECAST FOR CHRISTMAS AND BEYOND. AS FOR TEMPERATURES AND DEWPOINTS...HAVE STARTED WITH THE SHORTBLEND GRIDS THROUGH TONIGHT FOLLOWED BY THE SUPERBLEND INTO THE DAY SATURDAY. DID MAKE MINOR ADJUSTMENTS TO THESE PER THE EXPECTATIONS OF A RIDGE TO VALLEY TEMPERATURE SPLIT TONIGHT. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS...ESPECIALLY THE MAV...FOR THIS LOW QPF SITUATION TODAY AND THEN SIMILARLY CLOSE TO ZERO THROUGH THE REST OF THE FORECAST. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 305 PM EST FRI DEC 18 2015 HIGH PRESSURE WILL BE IN CONTROL ACROSS MUCH OF THE EASTERN CONUS AS WE HEAD INTO THE DAY SUNDAY...WITH KY ON THE WEST SIDE OF THE SYSTEM AND THEREFORE PULLING SOUTHERLY AIR INTO THE REGION. THIS WILL RESULT IN BOTH AN INCREASING AMOUNT OF MOISTURE ACROSS THE REGION...AS WELL AS WARMING TEMPERATURES. MEANWHILE...A LOW PRESSURE SYSTEM OVER THE CENTRAL PLAINS AND NORTHERN PLAINS WILL BEGIN PUSHING EASTWARD...WITH A COLD FRONT EXTENDING FROM THE UPPER GREAT LAKES AND JUST WEST OF THE MISSISSIPPI RIVER VALLEY BY SUNDAY EVENING. AS IT CONTINUES TO NEAR KY...MOISTURE WILL BE ON THE INCREASE...WITH CLOUDS THICKENING AND BUILDING DOWN DURING THE DAY MONDAY. THE COLD FRONT WILL SLOW DURING THE DAY MONDAY AND BECOME NEARLY STATIONARY ALONG THE OHIO RIVER AS IT CONTINUES TO WEAKEN THROUGH THE DAY TUESDAY. BY THIS POINT...MOISTURE INFLUX AND FRONTAL LIFT WILL PRODUCE RAIN ACROSS A GOOD PORTION OF THE CWA STARTING MONDAY MORNING AND CONTINUING THROUGH THE DAY TUESDAY AS THE FRONT BECOMES STALLED OUT. IN GOOD NEWS...THE CONTINUED SOUTHERLY FLOW WILL KEEP TEMPS WELL ABOVE NORMAL...AND ALL PRECIPITATION WILL FALL IN THE FORM OF RAIN. AS THE STATIONARY FRONT BEGINS TO FIZZLE OUT...ANOTHER TROUGHING PATTERN WILL SHIFT EASTWARD FROM THE CENTRAL PLAINS AND TOWARDS THE MISSISSIPPI AND OHIO RIVER VALLEYS WEDNESDAY. AS IT NEARS...WINDS WILL BE ON THE INCREASE AND BECOME MORE SOUTHERLY IN NATURE ONCE MORE...PULLING IN ANOTHER BOUT OF MOISTURE INTO THE AREA...AND KEEPING LIKELY RAIN CHANCES GOING THROUGH THE DAY WEDNESDAY. IT MAY ALSO RESULT IN JUST ENOUGH INSTABILITY AND STRONG ENOUGH LAPSE RATES TO PULL OUT A RUMBLE OR TWO OF THUNDER AS WELL. ANOTHER... STRONGER...COLD FRONT ASSOCIATED WITH THIS TROUGH WILL PUSH INTO WESTERN KY BY WEDNESDAY NIGHT/THURSDAY MORNING. THIS WILL AID SUBSTANTIALLY IN THE LIFT NEEDED TO PRODUCE MORE WIDESPREAD RAIN SHOWERS...CONTINUING AHEAD AND ALONG THE FRONT FROM WEDNESDAY NIGHT THROUGH MUCH OF THE DAY THURSDAY. THE DEVELOPMENT OF A SURFACE INVERSION WEDNESDAY NIGHT MAY BE ENOUGH TO DAMPEN ANY FURTHER THUNDER CONCERNS...THOUGH SOME GOOD WIND GUSTS MAY EASILY MIX DOWN TO THE SURFACE IN SOME OF THE HEAVIEST SHOWERS. WHILE MODEL TIMING THIS FAR OUT IN THE PERIOD IS STILL SOMEWHAT LACKING...THERE IS DECENT AGREEMENT THAT THE COLD FRONT SHOULD EXIT EAST OF KY BY 0Z CHRISTMAS/FRIDAY...BUT SHOULD GET HUNG UP IN THE HIGHER TERRAIN. IF THIS POSITION SHIFTS AT ALL...IT COULD MEAN THE DIFFERENCE BETWEEN SHOWERS COMING TO AN END CHRISTMAS EVE...OR SOME SHOWERS CONTINUING IN THE FAR SOUTHEAST DURING THE OVERNIGHT HOURS AND INTO THE DAY CHRISTMAS. ONCE AGAIN...THE CONTINUED SOUTHERLY FLOW DURING THIS TIME WILL LEAVE OUT ANY CONCERN FOR WINTRY PRECIP...AS TEMPERATURES WILL BE WELL ABOVE NORMAL. IN FACT...WOULDN/T BE SURPRISED IF SOME LATE DECEMBER TEMPERATURE RECORDS ARE BROKEN DURING THIS FORECAST TIME PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1150 AM EST FRI DEC 18 2015 LOW LEVEL CLOUDS REMAIN ACROSS MUCH OF EAST CENTRAL AND EASTERN KENTUCKY. THESE CLOUDS HAVE BROUGHT GENERALLY MVFR CIGS TO EASTERN KY AND SOME LOW END OF MVFR RANGE CIGS IN CENTRAL KY. ISOLATED SNOW SHOWERS AND FLURRIES ARE ALSO MOVING ACROSS THE AREA AND THESE WILL CONTINUE THROUGH ABOUT 21Z...BEFORE ENDING FROM WEST TO EAST THROUGH ABOUT 3Z. HOWEVER...THEY WILL BE FLEETING AND LIGHT ENOUGH AND SHOULD NOT REDUCE VIS BELOW MVFR...IF THAT. CIGS SHOULD GRADUALLY LIFT THROUGH THE FIRST 6 HOURS OF THE PERIOD TO VFR IN MOST LOCATIONS...BEFORE SCATTERING OUT THROUGH 6Z. WINDS WILL MAINLY FROM THE WEST AND BRISK...WITH SUSTAINED VALUES OF NEAR 10 KT AND GUSTS TO AROUND 20 KT THROUGH ABOUT 22Z...BUT SHOULD SLACKEN THIS EVENING WITH LOSS OF DAYTIME HEATING AND HIGH PRESSURE BUILDS IN AND THE PRESSURE GRADIENT RELAXES. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...JMW AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1151 AM EST FRI DEC 18 2015 .UPDATE... ISSUED AT 1145 AM EST FRI DEC 18 2015 SEVERAL REPORTS OF FLURRIES HAVE BEEN RECEIVED FROM ACROSS THE REGION THIS MORNING. RADAR TRENDS AND RECENT HRRR RUNS INDICATE THAT THE FLURRIES SHOULD OCCUR ON AND OFF FOR MOST OF THE DAY...AND LINGER INTO THE EVENING ACROSS THE SOUTHEAST. WITH PEAK HEATING AN ISOLATED SNOW SHOWER OR TWO WILL BE POSSIBLE...MAINLY ACROSS THE SOUTHEAST. WITH COLD AIR ADVECTION OCCURRING...TEMPERATURE SHOULD RISE VERY LITTLE TODAY. HOURLY GRIDS HAVE BEEN ADJUSTED BASED ON RECENT OBSERVATIONS. UPDATE ISSUED AT 810 AM EST FRI DEC 18 2015 SOME REPORTS OF FLURRIES HAVE BEEN RECEIVED AT THE OFFICE SO FAR EARLY THIS MORNING SO THE FORECAST IS ON TRACK WITH THAT RESPECT. OTHERWISE...HAVE ADJUSTED THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM EST FRI DEC 18 2015 07Z SFC ANALYSIS SHOWS HIGH PRESSURE EASING INTO THE STATE FROM THE WEST WHILE LOW PRESSURE IS NOT FAR OFF TO THE SOUTHEAST WITH ITS CYCLONIC FLOW STILL IMPACTING FAR EAST KENTUCKY. AS SUCH...LOW CLOUDS HAVE REDEVELOPED IN THE EAST AND PRESSED IN FROM THE NORTHWEST WHILE CAA CONTINUES ON LIGHT WEST TO NORTHWEST WINDS. ACCORDINGLY...TEMPERATURES ARE RATHER UNIFORM ACROSS THE AREA GENERALLY IN THE UPPER 20S AND LOWER 30S. DEWPOINTS ARE NOT FAR FROM DRY BULB VALUES AND THIS COULD LEAD TO SOME PATCHY FOG NEAR BODIES OF WATER TOWARD DAWN. FINALLY...THE LOWER CLOUDS COULD ALSO BE DROPPING A FEW VERY LIGHT SNOW SHOWERS OR FLURRIES...THOUGH THE LOCAL RADARS ARE SHOWING NO RETURNS AT THE MOMENT. THE MODELS ARE IN EXCELLENT AGREEMENT IN THE SHORT TERM AS THEY ALL DEPICT A LARGE TROUGH ROLLING THROUGH THE GREAT LAKES WHILE BOTTOMING OUT OVER KENTUCKY EARLY THIS MORNING. AS THE AXIS OF THIS 5H TROUGH PASSES PLENTY OF SHORTWAVE ENERGY WILL ACCOMPANY IT CROSSING OVER EASTERN KENTUCKY THROUGH 00Z SATURDAY. IN THE WAKE OF THE TROUGH...HEIGHTS WILL SLOWLY CLIMB ABOVE KENTUCKY FOR SATURDAY WITH ANY SIGNIFICANT ENERGY STAYING OFF TO THE NORTHEAST OF THE CWA. GIVEN THE MODEL AGREEMENT HAVE FAVORED THE HIGHER RESOLUTION GUIDANCE FROM THE HRRR AND NAM12 FOR THE SHORT TERM PORTION OF THE FORECAST. SENSIBLE WEATHER WILL FEATURE A CHILLY START THROUGH EAST KENTUCKY UNDER THE INCREASING INFLUENCE OF HIGH PRESSURE WHILE LOW CLOUDS PROVIDE A SMALL CHANCE FOR SOME SNOWFLAKES IN THE AIR...MAINLY IN THE FORM OF FLURRIES. A COMPONENT OF UPSLOPE FLOW SHOULD BE ABLE TO ACTIVATE THE LINGERING LOW LEVEL MOISTURE FOR SHOW SHOWERS IN THE HIGHER TERRAIN NEAR THE VIRGINIA BORDER LATER THIS MORNING. IN THESE LOCATIONS CANNOT RULE OUT A DUSTING OF SNOW THAT WILL ALMOST CERTAINLY MELT ON CONTACT WITH THE STILL WARM ROAD SURFACES AND GROUND. THE THREAT FOR LIGHT PCPN WANES FROM WEST TO EAST LATER TODAY WITH THE LOW CLOUDS LIFTING AND BREAKING UP BY EVENING. THE LOSS OF MOST OF THE CLOUDS WILL SET THE STAGE FOR ANOTHER CHILLY NIGHT THROUGHOUT THE CWA WITH A SMALL RIDGE TO VALLEY TEMPERATURE SPLIT LIKELY. SATURDAY WILL BE SEASONABLY COOL DESPITE NEAR FULL SUNSHINE AS THE HIGH MOVES RIGHT OVER HEAD. OF NOTE...THESE NEXT TWO DAYS MAY END UP BEING THE COLDEST OF DECEMBER GIVEN THE SHAPE OF THE UPCOMING FORECAST FOR CHRISTMAS AND BEYOND. AS FOR TEMPERATURES AND DEWPOINTS...HAVE STARTED WITH THE SHORTBLEND GRIDS THROUGH TONIGHT FOLLOWED BY THE SUPERBLEND INTO THE DAY SATURDAY. DID MAKE MINOR ADJUSTMENTS TO THESE PER THE EXPECTATIONS OF A RIDGE TO VALLEY TEMPERATURE SPLIT TONIGHT. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS...ESPECIALLY THE MAV...FOR THIS LOW QPF SITUATION TODAY AND THEN SIMILARLY CLOSE TO ZERO THROUGH THE REST OF THE FORECAST. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 305 AM EST FRI DEC 18 2015 UPPER LEVEL PATTERN WILL AGAIN REVERT BACK TO A RIDGE IN THE EAST AND TROUGH OUT WEST AS WE HEAD LATE INTO THE WEEKEND AND THROUGH CHRISTMAS WEEK. THIS WILL MEAN A RETURN TO ABOVE NORMAL TEMPERATURES THROUGHOUT THE PERIOD. THE REMAINDER OF THE WEEKEND IS SHAPING UP TO BE DRY AS A SURFACE RIDGE PUSHES EAST ACROSS THE REGION. THIS SHOULD MAKE FOR A MILD AND PLEASANT END TO THE WEEKEND. THE WEATHER WILL TURN MORE UNSETTLED BY LATE SUNDAY NIGHT AND MONDAY AS A FIRST OF MANY SHORTWAVE TROUGHS PUSH ACROSS THE CENTRAL PLAINS AND INTO THE GREAT LAKES...DRAGGING A COLD FRONT ACROSS EASTERN KENTUCKY. BEST RAIN CHANCES WILL COME MONDAY MORNING THROUGH THE AFTERNOON...AS THE FRONT PRESSES EASTWARD. CONFIDENCE IS INCREASING FOR A WET MONDAY ACROSS EASTERN KENTUCKY AS MODELS ARE IN GOOD AGREEMENT ON THE TIMING OF THIS FRONTAL BOUNDARY. MONDAY NIGHT AND TUESDAY COULD TREND DRIER IF THE FRONT CAN PUSH ON TO THE EAST AND SOUTH. HOWEVER...SOME MODELS SUGGESTING THE FRONT COULD HANG UP OVER THE AREA AND KEEP THE WEATHER UNSETTLED INTO TUESDAY. FOR NOW...WILL SETTLE ON LOWER POPS MONDAY NIGHT THROUGH TUESDAY AS FORCING WILL BE WEAK DURING THIS PERIOD. BY TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...PLENTY OF UNCERTAINTY ON TIMING OF RAIN CHANCES...BUT LOOKS LIKE A GENERIC WET PERIOD POTENTIALLY AS A STRONGER TROUGH EJECTS OUT OF THE CENTRAL PLAINS. EXACT TRACK AND STRENGTH WILL DETERMINE HOW MUCH PRECIPITATION FALLS. IF THE TRACK OF THE SURFACE LOW TO OUT TO THE WEST... SOUTH/SOUTHEAST WINDS MAY PRODUCE DOWNSLOPING CONDITIONS AND CUT INTO RAINFALL POTENTIAL. HOWEVER...THIS FAR OUT...HARD TO COME INTO A GENERAL AGREEMENT YET. WILL KEEP POPS IN THE HIGH CHANCE/LIKELY CATEGORY FOR NOW. AS WE HEAD INTO CHRISTMAS EVE/CHRISTMAS...IT LOOKS LIKE MODELS ARE TRENDING TOWARDS AN EXITING COLD FRONT...WITH DRIER WEATHER SPREADING INTO THE REGION. HOWEVER...AGAIN...PLENTY OF UNCERTAINTY IN THAT FORECAST...AS THE FRONT COULD EASILY GET HUNG UP TO THE NORTH AND STALL OVER THE AREA...KEEPING A CHANCE OF RAIN OVER THE AREA. FOR NOW WILL DRY THINGS OUT FOR CHRISTMAS...BUT IT COULD CERTAINLY END UP WETTER. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1150 AM EST FRI DEC 18 2015 LOW LEVEL CLOUDS REMAIN ACROSS MUCH OF EAST CENTRAL AND EASTERN KENTUCKY. THESE CLOUDS HAVE BROUGHT GENERALLY MVFR CIGS TO EASTERN KY AND SOME LOW END OF MVFR RANGE CIGS IN CENTRAL KY. ISOLATED SNOW SHOWERS AND FLURRIES ARE ALSO MOVING ACROSS THE AREA AND THESE WILL CONTINUE THROUGH ABOUT 21Z...BEFORE ENDING FROM WEST TO EAST THROUGH ABOUT 3Z. HOWEVER...THEY WILL BE FLEETING AND LIGHT ENOUGH AND SHOULD NOT REDUCE VIS BELOW MVFR...IF THAT. CIGS SHOULD GRADUALLY LIFT THROUGH THE FIRST 6 HOURS OF THE PERIOD TO VFR IN MOST LOCATIONS...BEFORE SCATTERING OUT THROUGH 6Z. WINDS WILL MAINLY FROM THE WEST AND BRISK...WITH SUSTAINED VALUES OF NEAR 10 KT AND GUSTS TO AROUND 20 KT THROUGH ABOUT 22Z...BUT SHOULD SLACKEN THIS EVENING WITH LOSS OF DAYTIME HEATING AND HIGH PRESSURE BUILDS IN AND THE PRESSURE GRADIENT RELAXES. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...KAS AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
810 AM EST FRI DEC 18 2015 .UPDATE... ISSUED AT 810 AM EST FRI DEC 18 2015 SOME REPORTS OF FLURRIES HAVE BEEN RECEIVED AT THE OFFICE SO FAR EARLY THIS MORNING SO THE FORECAST IS ON TRACK WITH THAT RESPECT. OTHERWISE...HAVE ADJUSTED THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM EST FRI DEC 18 2015 07Z SFC ANALYSIS SHOWS HIGH PRESSURE EASING INTO THE STATE FROM THE WEST WHILE LOW PRESSURE IS NOT FAR OFF TO THE SOUTHEAST WITH ITS CYCLONIC FLOW STILL IMPACTING FAR EAST KENTUCKY. AS SUCH...LOW CLOUDS HAVE REDEVELOPED IN THE EAST AND PRESSED IN FROM THE NORTHWEST WHILE CAA CONTINUES ON LIGHT WEST TO NORTHWEST WINDS. ACCORDINGLY...TEMPERATURES ARE RATHER UNIFORM ACROSS THE AREA GENERALLY IN THE UPPER 20S AND LOWER 30S. DEWPOINTS ARE NOT FAR FROM DRY BULB VALUES AND THIS COULD LEAD TO SOME PATCHY FOG NEAR BODIES OF WATER TOWARD DAWN. FINALLY...THE LOWER CLOUDS COULD ALSO BE DROPPING A FEW VERY LIGHT SNOW SHOWERS OR FLURRIES...THOUGH THE LOCAL RADARS ARE SHOWING NO RETURNS AT THE MOMENT. THE MODELS ARE IN EXCELLENT AGREEMENT IN THE SHORT TERM AS THEY ALL DEPICT A LARGE TROUGH ROLLING THROUGH THE GREAT LAKES WHILE BOTTOMING OUT OVER KENTUCKY EARLY THIS MORNING. AS THE AXIS OF THIS 5H TROUGH PASSES PLENTY OF SHORTWAVE ENERGY WILL ACCOMPANY IT CROSSING OVER EASTERN KENTUCKY THROUGH 00Z SATURDAY. IN THE WAKE OF THE TROUGH...HEIGHTS WILL SLOWLY CLIMB ABOVE KENTUCKY FOR SATURDAY WITH ANY SIGNIFICANT ENERGY STAYING OFF TO THE NORTHEAST OF THE CWA. GIVEN THE MODEL AGREEMENT HAVE FAVORED THE HIGHER RESOLUTION GUIDANCE FROM THE HRRR AND NAM12 FOR THE SHORT TERM PORTION OF THE FORECAST. SENSIBLE WEATHER WILL FEATURE A CHILLY START THROUGH EAST KENTUCKY UNDER THE INCREASING INFLUENCE OF HIGH PRESSURE WHILE LOW CLOUDS PROVIDE A SMALL CHANCE FOR SOME SNOWFLAKES IN THE AIR...MAINLY IN THE FORM OF FLURRIES. A COMPONENT OF UPSLOPE FLOW SHOULD BE ABLE TO ACTIVATE THE LINGERING LOW LEVEL MOISTURE FOR SHOW SHOWERS IN THE HIGHER TERRAIN NEAR THE VIRGINIA BORDER LATER THIS MORNING. IN THESE LOCATIONS CANNOT RULE OUT A DUSTING OF SNOW THAT WILL ALMOST CERTAINLY MELT ON CONTACT WITH THE STILL WARM ROAD SURFACES AND GROUND. THE THREAT FOR LIGHT PCPN WANES FROM WEST TO EAST LATER TODAY WITH THE LOW CLOUDS LIFTING AND BREAKING UP BY EVENING. THE LOSS OF MOST OF THE CLOUDS WILL SET THE STAGE FOR ANOTHER CHILLY NIGHT THROUGHOUT THE CWA WITH A SMALL RIDGE TO VALLEY TEMPERATURE SPLIT LIKELY. SATURDAY WILL BE SEASONABLY COOL DESPITE NEAR FULL SUNSHINE AS THE HIGH MOVES RIGHT OVER HEAD. OF NOTE...THESE NEXT TWO DAYS MAY END UP BEING THE COLDEST OF DECEMBER GIVEN THE SHAPE OF THE UPCOMING FORECAST FOR CHRISTMAS AND BEYOND. AS FOR TEMPERATURES AND DEWPOINTS...HAVE STARTED WITH THE SHORTBLEND GRIDS THROUGH TONIGHT FOLLOWED BY THE SUPERBLEND INTO THE DAY SATURDAY. DID MAKE MINOR ADJUSTMENTS TO THESE PER THE EXPECTATIONS OF A RIDGE TO VALLEY TEMPERATURE SPLIT TONIGHT. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS...ESPECIALLY THE MAV...FOR THIS LOW QPF SITUATION TODAY AND THEN SIMILARLY CLOSE TO ZERO THROUGH THE REST OF THE FORECAST. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 305 AM EST FRI DEC 18 2015 UPPER LEVEL PATTERN WILL AGAIN REVERT BACK TO A RIDGE IN THE EAST AND TROUGH OUT WEST AS WE HEAD LATE INTO THE WEEKEND AND THROUGH CHRISTMAS WEEK. THIS WILL MEAN A RETURN TO ABOVE NORMAL TEMPERATURES THROUGHOUT THE PERIOD. THE REMAINDER OF THE WEEKEND IS SHAPING UP TO BE DRY AS A SURFACE RIDGE PUSHES EAST ACROSS THE REGION. THIS SHOULD MAKE FOR A MILD AND PLEASANT END TO THE WEEKEND. THE WEATHER WILL TURN MORE UNSETTLED BY LATE SUNDAY NIGHT AND MONDAY AS A FIRST OF MANY SHORTWAVE TROUGHS PUSH ACROSS THE CENTRAL PLAINS AND INTO THE GREAT LAKES...DRAGGING A COLD FRONT ACROSS EASTERN KENTUCKY. BEST RAIN CHANCES WILL COME MONDAY MORNING THROUGH THE AFTERNOON...AS THE FRONT PRESSES EASTWARD. CONFIDENCE IS INCREASING FOR A WET MONDAY ACROSS EASTERN KENTUCKY AS MODELS ARE IN GOOD AGREEMENT ON THE TIMING OF THIS FRONTAL BOUNDARY. MONDAY NIGHT AND TUESDAY COULD TREND DRIER IF THE FRONT CAN PUSH ON TO THE EAST AND SOUTH. HOWEVER...SOME MODELS SUGGESTING THE FRONT COULD HANG UP OVER THE AREA AND KEEP THE WEATHER UNSETTLED INTO TUESDAY. FOR NOW...WILL SETTLE ON LOWER POPS MONDAY NIGHT THROUGH TUESDAY AS FORCING WILL BE WEAK DURING THIS PERIOD. BY TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...PLENTY OF UNCERTAINTY ON TIMING OF RAIN CHANCES...BUT LOOKS LIKE A GENERIC WET PERIOD POTENTIALLY AS A STRONGER TROUGH EJECTS OUT OF THE CENTRAL PLAINS. EXACT TRACK AND STRENGTH WILL DETERMINE HOW MUCH PRECIPITATION FALLS. IF THE TRACK OF THE SURFACE LOW TO OUT TO THE WEST... SOUTH/SOUTHEAST WINDS MAY PRODUCE DOWNSLOPING CONDITIONS AND CUT INTO RAINFALL POTENTIAL. HOWEVER...THIS FAR OUT...HARD TO COME INTO A GENERAL AGREEMENT YET. WILL KEEP POPS IN THE HIGH CHANCE/LIKELY CATEGORY FOR NOW. AS WE HEAD INTO CHRISTMAS EVE/CHRISTMAS...IT LOOKS LIKE MODELS ARE TRENDING TOWARDS AN EXITING COLD FRONT...WITH DRIER WEATHER SPREADING INTO THE REGION. HOWEVER...AGAIN...PLENTY OF UNCERTAINTY IN THAT FORECAST...AS THE FRONT COULD EASILY GET HUNG UP TO THE NORTH AND STALL OVER THE AREA...KEEPING A CHANCE OF RAIN OVER THE AREA. FOR NOW WILL DRY THINGS OUT FOR CHRISTMAS...BUT IT COULD CERTAINLY END UP WETTER. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 730 AM EST FRI DEC 18 2015 LOW LEVEL CLOUDS HAVE OVERSPREAD EASTERN KENTUCKY. THESE CLOUDS HAVE BROUGHT LOW MVFR CIGS TO ALL AIRPORTS. SOME ISOLATED SNOW SHOWERS AND FLURRIES ARE ALSO MOVING ACROSS THE AREA AND THESE WILL CONTINUE INTO THE DAY. HOWEVER...THEY WILL BE FLEETING AND LIGHT ENOUGH TO NOT HAVE ANY IMPACTS ON THE TAF SITES. THE LOW PRECIPITATION CHANCES WILL TAPER OFF FROM WEST TO EAST THROUGH OUT THE AFTERNOON. CIGS WILL ALSO LIFT AND BREAK UP WITH TIME WITH VFR CONDITIONS ANTICIPATED TONIGHT. WINDS ON LATER TODAY WILL SHIFT TO THE WEST AND BE BRISK...WITH SUSTAINED VALUES OF NEAR 10 KTS AND GUSTS TO BETWEEN 15 AND 20 KTS POSSIBLE THROUGH LATE AFTERNOON. LOOK FOR THE WINDS TO DIE OFF THIS EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...GREIF LONG TERM...KAS AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS JACKSON KY
305 AM EST FRI DEC 18 2015 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM EST FRI DEC 18 2015 07Z SFC ANALYSIS SHOWS HIGH PRESSURE EASING INTO THE STATE FROM THE WEST WHILE LOW PRESSURE IS NOT FAR OFF TO THE SOUTHEAST WITH ITS CYCLONIC FLOW STILL IMPACTING FAR EAST KENTUCKY. AS SUCH...LOW CLOUDS HAVE REDEVELOPED IN THE EAST AND PRESSED IN FROM THE NORTHWEST WHILE CAA CONTINUES ON LIGHT WEST TO NORTHWEST WINDS. ACCORDINGLY...TEMPERATURES ARE RATHER UNIFORM ACROSS THE AREA GENERALLY IN THE UPPER 20S AND LOWER 30S. DEWPOINTS ARE NOT FAR FROM DRY BULB VALUES AND THIS COULD LEAD TO SOME PATCHY FOG NEAR BODIES OF WATER TOWARD DAWN. FINALLY...THE LOWER CLOUDS COULD ALSO BE DROPPING A FEW VERY LIGHT SNOW SHOWERS OR FLURRIES...THOUGH THE LOCAL RADARS ARE SHOWING NO RETURNS AT THE MOMENT. THE MODELS ARE IN EXCELLENT AGREEMENT IN THE SHORT TERM AS THEY ALL DEPICT A LARGE TROUGH ROLLING THROUGH THE GREAT LAKES WHILE BOTTOMING OUT OVER KENTUCKY EARLY THIS MORNING. AS THE AXIS OF THIS 5H TROUGH PASSES PLENTY OF SHORTWAVE ENERGY WILL ACCOMPANY IT CROSSING OVER EASTERN KENTUCKY THROUGH 00Z SATURDAY. IN THE WAKE OF THE TROUGH...HEIGHTS WILL SLOWLY CLIMB ABOVE KENTUCKY FOR SATURDAY WITH ANY SIGNIFICANT ENERGY STAYING OFF TO THE NORTHEAST OF THE CWA. GIVEN THE MODEL AGREEMENT HAVE FAVORED THE HIGHER RESOLUTION GUIDANCE FROM THE HRRR AND NAM12 FOR THE SHORT TERM PORTION OF THE FORECAST. SENSIBLE WEATHER WILL FEATURE A CHILLY START THROUGH EAST KENTUCKY UNDER THE INCREASING INFLUENCE OF HIGH PRESSURE WHILE LOW CLOUDS PROVIDE A SMALL CHANCE FOR SOME SNOWFLAKES IN THE AIR...MAINLY IN THE FORM OF FLURRIES. A COMPONENT OF UPSLOPE FLOW SHOULD BE ABLE TO ACTIVATE THE LINGERING LOW LEVEL MOISTURE FOR SHOW SHOWERS IN THE HIGHER TERRAIN NEAR THE VIRGINIA BORDER LATER THIS MORNING. IN THESE LOCATIONS CANNOT RULE OUT A DUSTING OF SNOW THAT WILL ALMOST CERTAINLY MELT ON CONTACT WITH THE STILL WARM ROAD SURFACES AND GROUND. THE THREAT FOR LIGHT PCPN WANES FROM WEST TO EAST LATER TODAY WITH THE LOW CLOUDS LIFTING AND BREAKING UP BY EVENING. THE LOSS OF MOST OF THE CLOUDS WILL SET THE STAGE FOR ANOTHER CHILLY NIGHT THROUGHOUT THE CWA WITH A SMALL RIDGE TO VALLEY TEMPERATURE SPLIT LIKELY. SATURDAY WILL BE SEASONABLY COOL DESPITE NEAR FULL SUNSHINE AS THE HIGH MOVES RIGHT OVER HEAD. OF NOTE...THESE NEXT TWO DAYS MAY END UP BEING THE COLDEST OF DECEMBER GIVEN THE SHAPE OF THE UPCOMING FORECAST FOR CHRISTMAS AND BEYOND. AS FOR TEMPERATURES AND DEWPOINTS...HAVE STARTED WITH THE SHORTBLEND GRIDS THROUGH TONIGHT FOLLOWED BY THE SUPERBLEND INTO THE DAY SATURDAY. DID MAKE MINOR ADJUSTMENTS TO THESE PER THE EXPECTATIONS OF A RIDGE TO VALLEY TEMPERATURE SPLIT TONIGHT. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS...ESPECIALLY THE MAV...FOR THIS LOW QPF SITUATION TODAY AND THEN SIMILARLY CLOSE TO ZERO THROUGH THE REST OF THE FORECAST. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 305 AM EST FRI DEC 18 2015 UPPER LEVEL PATTERN WILL AGAIN REVERT BACK TO A RIDGE IN THE EAST AND TROUGH OUT WEST AS WE HEAD LATE INTO THE WEEKEND AND THROUGH CHRISTMAS WEEK. THIS WILL MEAN A RETURN TO ABOVE NORMAL TEMPERATURES THROUGHOUT THE PERIOD. THE REMAINDER OF THE WEEKEND IS SHAPING UP TO BE DRY AS A SURFACE RIDGE PUSHES EAST ACROSS THE REGION. THIS SHOULD MAKE FOR A MILD AND PLEASANT END TO THE WEEKEND. THE WEATHER WILL TURN MORE UNSETTLED BY LATE SUNDAY NIGHT AND MONDAY AS A FIRST OF MANY SHORTWAVE TROUGHS PUSH ACROSS THE CENTRAL PLAINS AND INTO THE GREAT LAKES...DRAGGING A COLD FRONT ACROSS EASTERN KENTUCKY. BEST RAIN CHANCES WILL COME MONDAY MORNING THROUGH THE AFTERNOON...AS THE FRONT PRESSES EASTWARD. CONFIDENCE IS INCREASING FOR A WET MONDAY ACROSS EASTERN KENTUCKY AS MODELS ARE IN GOOD AGREEMENT ON THE TIMING OF THIS FRONTAL BOUNDARY. MONDAY NIGHT AND TUESDAY COULD TREND DRIER IF THE FRONT CAN PUSH ON TO THE EAST AND SOUTH. HOWEVER...SOME MODELS SUGGESTING THE FRONT COULD HANG UP OVER THE AREA AND KEEP THE WEATHER UNSETTLED INTO TUESDAY. FOR NOW...WILL SETTLE ON LOWER POPS MONDAY NIGHT THROUGH TUESDAY AS FORCING WILL BE WEAK DURING THIS PERIOD. BY TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...PLENTY OF UNCERTAINTY ON TIMING OF RAIN CHANCES...BUT LOOKS LIKE A GENERIC WET PERIOD POTENTIALLY AS A STRONGER TROUGH EJECTS OUT OF THE CENTRAL PLAINS. EXACT TRACK AND STRENGTH WILL DETERMINE HOW MUCH PRECIPITATION FALLS. IF THE TRACK OF THE SURFACE LOW TO OUT TO THE WEST... SOUTH/SOUTHEAST WINDS MAY PRODUCE DOWNSLOPING CONDITIONS AND CUT INTO RAINFALL POTENTIAL. HOWEVER...THIS FAR OUT...HARD TO COME INTO A GENERAL AGREEMENT YET. WILL KEEP POPS IN THE HIGH CHANCE/LIKELY CATEGORY FOR NOW. AS WE HEAD INTO CHRISTMAS EVE/CHRISTMAS...IT LOOKS LIKE MODELS ARE TRENDING TOWARDS AN EXITING COLD FRONT...WITH DRIER WEATHER SPREADING INTO THE REGION. HOWEVER...AGAIN...PLENTY OF UNCERTAINTY IN THAT FORECAST...AS THE FRONT COULD EASILY GET HUNG UP TO THE NORTH AND STALL OVER THE AREA...KEEPING A CHANCE OF RAIN OVER THE AREA. FOR NOW WILL DRY THINGS OUT FOR CHRISTMAS...BUT IT COULD CERTAINLY END UP WETTER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 110 AM EST FRI DEC 18 2015 MOSTLY CLEAR SKIES AND VFR CONDITIONS WERE IN PLACE AT ALL FIVE TAF SITES AT TAF ISSUANCE. THIS TREND IS EXPECTED TO BREAK SHORTLY...THOUGH...AS A LARGE AREA OF LOW LEVEL CLOUD COVER WILL ONCE AGAIN OVERSPREAD EASTERN KENTUCKY FROM THE NORTHWEST AND LOCALLY FORM IN THE EAST. THESE CLOUDS WILL BRING MVFR CIGS TO ALL AIRPORTS LOCATIONS BY THE PRE-DAWN HOURS. SOME ISOLATED SNOW SHOWERS AND FLURRIES WILL ALSO MOVE ACROSS THE AREA INTO DAWN AND CONTINUE THROUGH THE DAY FRIDAY. HOWEVER...THESE WILL BE FLEETING AND LIGHT ENOUGH TO NOT HAVE ANY IMPACTS ON THE TAF SITES. THE LOW PRECIPITATION CHANCES WILL TAPER OFF FROM WEST TO EAST THROUGH OUT THE DAY ON FRIDAY. WINDS ON FRIDAY WILL SHIFT TO THE WEST AND BE BRISK...WITH SUSTAINED VALUES OF NEAR 10 KTS AND GUSTS TO BETWEEN 15 AND 20 KTS POSSIBLE THROUGH LATE AFTERNOON. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GREIF LONG TERM...KAS AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
135 AM EST FRI DEC 18 2015 .UPDATE... ISSUED AT 135 AM EST FRI DEC 18 2015 TEMPERATURES ARE FAIRLY UNIFORM ACROSS THE AREA ELEVATION-WISE EARLY THIS MORNING AS CAA IS FILTERING THE COLDER AND DRIER AIR MASS THROUGH THE CWA ON LIGHT WEST TO NORTHWEST WINDS. LOWER CLOUDS ARE STARTING TO MOVE IN FROM THE NORTHWEST AND THESE WILL FURTHER PROMOTE UNIFORMITY TO THE TEMPERATURES FOR THE REST OF THE NIGHT. DO EXPECT SOME SPOTTY LIGHT PCPN TO FALL FROM THESE LOWER CLOUDS INTO DAWN IN THE FORM OF VERY LIGHT SNOW SHOWERS...BUT MAINLY JUST FLURRIES. HAVE UPDATED THE FORECAST TO REFLECT THIS AND ALSO TO INCORPORATE THE LATEST SHORTBLEND GUIDANCE...CURRENT OBS...AND TRENDS INTO THE T AND TD GRIDS. THESE ALL HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 1044 PM EST THU DEC 17 2015 A CHALLENGING TEMPERATURE FORECAST FOR THE REMAINDER OF THE OVERNIGHT PERIOD. LOW LEVEL CLOUD COVER OVER THE PAST COUPLE OF HOURS HAS ACTUALLY BACK BUILT TO THE NORTHWEST OVER THE EASTERN THIRD OF OUR FORECAST...AGAINST THE PREVAILING LOW LEVEL FLOW NO LESS. THEREFORE...RIDGETOP TEMPERATURES TO OUR EAST HAVE NOT BEEN FALLING QUITE AS FAST AS ORIGINALLY FORECAST. THE DEEPER AND MORE SHELTERED VALLEYS TO OUR EAST AND NORTHEAST...WHERE CLOUD COVER HAS NOT YET FILLED IN...HAVE BEEN DROPPING OF FASTER THAN EXPECTED...BUT WITH CLOUDS CONTINUING TO PROGRESS WESTWARD...THIS STEADY DROP MAY BE SLOWED DURING THE REST OF THE NIGHT...SO WENT WITH A MORE WELL DEFINED RIDGE VALLEY DIFFERENCE IN OUR EASTERN THIRD OF COUNTIES...WITH SIMILAR VALLEY TEMPS FOR OVERNIGHT LOWS AND WARMER RIDGE TEMPS. AS FOR THE REST OF THE AREA...TEMPERATURES HAVE BEEN DROPPING FASTER THAN EXPECTED IN SOME LOCATIONS AND ABOUT THE SAME AS ORIGINALLY FORECAST IN OTHERS. ALL IN ALL DECIDED TO USE AN HOURLY TEMPERATURE CURVE THROUGH 12Z FRIDAY USING CURRENT TRENDS IN OBS ACROSS THE FORECAST...WITH SOME SLIGHT MODIFICATIONS. OVERNIGHT LOWS ARE NOW FORECAST TO NOT BE QUITE AS COLD AS BEFORE DUE TO THE BACK BUILDING CLOUD COVER IN OUR EAST AND THE FAST APPROACHING CLOUDS COMING IN FROM THE WEST. SOME MINOR ADJUSTMENTS WERE ALSO MADE TO THE CLOUD COVER FORECAST FOR OUR EASTERN COUNTIES TO ACCOUNT FOR TRENDS OBSERVED OVER THE PAST FEW HOURS. THE REST OF THE FORECAST WAS IN GOOD SHAPE. UPDATE ISSUED AT 700 EST THU DEC 17 2015 CLOUD COVER THAT WAS WIDESPREAD THROUGH OUT THE DAY HAS EXITED THE AREA MUCH MORE QUICKLY THAN ORIGINALLY FORECAST. IN FACT...MOST OF EASTERN KENTUCKY HAS BEEN EXPERIENCING MOSTLY CLEAR SKIES FOR THE PAST HOUR OR SO. THEREFORE...SKY COVER FORECAST FOR THE NEXT SEVERAL HOURS HAS BEEN UPDATED TO REFLECT CURRENT TRENDS. TEMPERATURES ACROSS THE AREA HAVE ALSO BEEN FALLING A BIT MORE QUICKLY DUE TO THE LACK OF CLOUD COVER...SO THE HOURLY TEMPS WERE ADJUSTED WITH THE LATEST OBS DATA. WILL CONTINUE TO MONITOR TO DETERMINE WHETHER OR NOT OVERNIGHT LOWS NEED TO BE LOWERED ANY. IT WILL DEPEND ON HOW QUICKLY THE AREA OF CLOUDS CURRENT MOVING ACROSS THE OHIO RIVER REACHES OUR AREA TONIGHT. THE REST OF THE FORECAST WAS IN GOOD SHAPE. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 315 PM EST THU DEC 17 2015 AN DRY SLOT BETWEEN A DEPARTING COLD FRONT AND INITIAL SHORTWAVE AND AN APPROACHING UPPER TROUGH IS GRADUALLY SPREADING INTO EASTERN KY ATTM. THIS CLEARING HAS WORKED INTO THE WESTERN HALF OF THE AREA...WHILE LOW CLOUDS LINGER ACROSS THE FAR SOUTHEAST WHERE A FEW WEAK RETURNS LIKELY FORM DRIZZLE LINGER NEAR THE VA BORDER FROM PIKE COUNTY SOUTHWEST TO HARLAN COUNTY. TEMPERATURES THAT HAD DROPPED INTO THE LOWER 40S ACROSS THE WESTERN PART OF THE AREA HAVE RECOVERED BACK TO THE MID TO UPPER 40S. FROM TONIGHT INTO FRIDAY...A RIDGE OVER PARTS OF THE ATLANTIC WILL SHIFT EAST WHILE A RIDGE OVER PARTS OF THE PACIFIC BUILDS TOWARD THE SOUTHWESTERN US. IN BETWEEN A MID LEVEL TROUGH WILL MOVE INTO THE EASTERN CONUS WITH A SHORTWAVE APPROACHING THE LOWER OH VALLEY TONIGHT AND THEN MOVING ACROSS THE AREA ON FRIDAY. THE HEART OF THE COLDER AIRMASS WILL MOVE ACROSS THE AREA AT THAT POINT. AS THE TROUGH DEPARTS ON FRIDAY EVENING AND FRIDAY NIGHT...RIDGING AT THE SFC AND ALOFT WILL BUILD INTO THE AREA. THE 12Z NAM AND A COUPLE OF RECENT RAP RUNS SUGGEST MOISTURE MAY BECOME SUFFICIENTLY DEEP FOR LIGHT NON MEASURABLE PRECIPITATION OVERNIGHT...TOWARD DAWN. TOP DOWN APPROACH OF THE FORECAST SOUNDINGS INDICATE THAT CLOUDS WILL BE BORDERLINE INITIALLY FOR THE PRESENCE OF ICE CRYSTALS SO IF ANYTHING FALLS LATE TONIGHT IT MIGHT BE A FEW SPRINKLES OR VERY LIGHT DRIZZLE OR FLURRIES OR A MIXTURE OF BOTH. HOWEVER...MODEL GUIDANCE ALSO INDICATE THAT THE MOISTURE SHOULD BE SUFFICIENTLY DEEP FOR ICE TO BE PRESENT IN THE CLOUDS BY AROUND DAWN ON FRIDAY. ALSO...EVEN WHERE SFC TEMPS ARE A LITTLE BIT ABOVE THE FREEZING MARK...DRY ADIABATIC LAPSE RATES AND RELATIVELY DRY SUB CLOUDS LAYER SHOULD LEAD TO ANY PRECIPITATION ON FRIDAY FALLING AS SNOW. HIGHER MOMENTUM FROM STRONGER WINDS ALOFT SHOULD ALSO MIX DOWN...WITH GUSTS AS HIGH AS 25 TO 30 MPH POSSIBLE. THE PATTERN WILL FAVOR THE SW VALLEYS BEING A BIT COLDER THAN AREAS TO THE NORTHEAST DUE TO EARLIER CLEARING AND A QUICKER SLACKENING TO THE WINDS. THE COLDEST NIGHT OF THE NEXT SEVERAL SHOULD NOT OCCUR UNTIL THE LONG TERM PERIOD...ON SATURDAY NIGHT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 320 PM EST THU DEC 17 2015 THE WEEKEND WILL FEATURE A PROGRESSIVE UPPER LEVEL RIDGE AXIS SITUATED OVER THE OH VALLEY...ALONG WITH SFC HIGH PRESSURE. THIS WILL PROVIDE US WITH A DRY AND SUN-FILLED WEEKEND. FRIDAY NIGHT TEMPERATURES WILL BE ON THE CHILLY SIDE WITH MOST LOCATIONS DIPPING INTO THE MID 20S. HOWEVER...WITH AMPLE SUNSHINE...AFTERNOON TEMPS SHOULD RECOVER INTO THE 40S WHICH IS NEAR NORMAL FOR THIS TIME OF YEAR. WITH THE HIGH PRESSURE CENTERED OVER US SATURDAY NIGHT...TEMPS WILL BE THE COLDEST OF THE MONTH WITH VALLEY LOCATIONS FALLING NEAR 20 DEGREES. AS SOUTHERLY FLOW RETURNS ON SUNDAY...TEMPS WILL BE ABOVE NORMAL YET AGAIN WITH HIGHS WARMING INTO THE LOW 50S. A MILD AND WET PERIOD OF WEATHER IS EXPECTED AS WE MOVE INTO THE WORK WEEK. UPPER LEVEL FLOW WILL BE FAIRLY ZONAL WITH A SERIES OF WEAK IMPULSES/TROUGHS MOVING THROUGH KENTUCKY. THE 12Z GFS AND 00Z ECMWF DISAGREE ON TIMING AND AMPLIFICATION OF MANY OF THESE IMPULSES SO HAVE CONTINUED TO BE GENERAL WITH RAIN CHANCES. THAT BEING SAID...THE FIRST CHANCE FOR RAIN COMES ON MONDAY AS A COLD FRONT APPROACHES THE REGION. THE FRONT IS PROGGED TO STALL OVER KENTUCKY AS A SERIES OF WAVES MOVE ALONG THE BOUNDARY. THIS WILL BRING CONTINUED RAIN CHANCES THROUGH THE END OF THE PERIOD. THERE WILL BE AMPLE GULF MOISTURE FOR THESE WAVES TO TAP INTO SO RAIN AMOUNTS COULD AMOUNT UP TO 2 OR 3 INCHES OVER THE COURSE OF THE WEEK. TEMPERATURES NEXT WEEK WILL AVERAGE 10-20 DEGREES ABOVE NORMAL...POSSIBLE MAKING A RUN AT BREAKING RECORD HIGH TEMPS NEXT WEDNESDAY AND THURSDAY. ALSO...IF WE DON/T GET ANY SNOW ACCUMULATION ON FRIDAY...WE WILL MAKE A RUN AT THE ALL TIME LATEST MEASURABLE SNOW AT JACKSON WHICH WAS ON DECEMBER 29TH...2001. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 110 AM EST FRI DEC 18 2015 MOSTLY CLEAR SKIES AND VFR CONDITIONS WERE IN PLACE AT ALL FIVE TAF SITES AT TAF ISSUANCE. THIS TREND IS EXPECTED TO BREAK SHORTLY...THOUGH...AS A LARGE AREA OF LOW LEVEL CLOUD COVER WILL ONCE AGAIN OVERSPREAD EASTERN KENTUCKY FROM THE NORTHWEST AND LOCALLY FORM IN THE EAST. THESE CLOUDS WILL BRING MVFR CIGS TO ALL AIRPORTS LOCATIONS BY THE PRE-DAWN HOURS. SOME ISOLATED SNOW SHOWERS AND FLURRIES WILL ALSO MOVE ACROSS THE AREA INTO DAWN AND CONTINUE THROUGH THE DAY FRIDAY. HOWEVER...THESE WILL BE FLEETING AND LIGHT ENOUGH TO NOT HAVE ANY IMPACTS ON THE TAF SITES. THE LOW PRECIPITATION CHANCES WILL TAPER OFF FROM WEST TO EAST THROUGH OUT THE DAY ON FRIDAY. WINDS ON FRIDAY WILL SHIFT TO THE WEST AND BE BRISK...WITH SUSTAINED VALUES OF NEAR 10 KTS AND GUSTS TO BETWEEN 15 AND 20 KTS POSSIBLE THROUGH LATE AFTERNOON. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...JP LONG TERM...JVM AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS CARIBOU ME
606 PM EST SAT DEC 19 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD TONIGHT INTO SUNDAY. A WARM FRONT WILL CROSS THE REGION MONDAY. A WEAK AREA OF LOW PRESSURE WILL MOVE NORTH OF THE STATE MONDAY NIGHT INTO TUESDAY. && .NEAR TERM /THROUGH SUNDAY/... 545 PM UPDATE: POPS WERE BUMPED UP ACROSS ALL OF THE FA WITH APCH OF A S/WV FROM HUDSON BAY AND A WEAKLY DEFINED SECONDARY SFC COLD FRONT WHICH WILL INCREASE THE CVRG OF ST LAWRENCE SEAWAY SN SN BANDING BY LATE THIS EVE. WE OPTD TO USE THE REG CANGEM MODEL... BACKED UP BY LATEST HRRR SIM HRLY RADAR REF WHICH SHOWS THE POTENTIAL OF SN BANDING. FOR THE PURPOSE OF THIS UPDATE...WE SHOW 3 BANDS...ONE IN THE FAR N...THE SECOND OVR N CNTRL AND A THIRD OVR DOWNEAST AREAS AS PER THE CANGEM MODEL...WHICH HAS HAD MODEST SUCCESS WITH THE PSNG OF SN BANDS IN THE PAST...BUT CERTAINLY WE ANTICIPATE CHGS WITH THE REAL TM SN BANDS WHICH WE CAN MAKE IN THE FORECAST GRIDS ON THE FLY. WE WILL ALSO ISSUE SPS STATEMENTS TO HIGHLIGHT MORE PRECISE PSNS AND MOVEMENTS OF BANDS ONCE THEY FORM OR MOVE INTO THE REGION FROM QB PROV. FOR NOW WE WILL MENTION LCLZD HIGHER SNFL AMOUNTS OF 1 TO 2 INCHES WITH BANDS AND LESS THAN AN INCH FOR AREAS NOT RECEIVING MUCH IN THE WAY OF HEAVIER SN BANDS. OTHERWISE...FCST HRLY TEMPS WERE UPDATED THRU THE OVRNGT BASED ON LATEST SFC OBS AND UNCHGD FCST LOW TEMPS ATTM POSTED AT 7 AM SUN. ORGNL DISC: MARKEDLY COLDER AIR WILL CONTINUE TO ADVECT INTO THE REGION TONIGHT WITH THE COLD UPPER TROUGH PASSAGE NEAR MIDNIGHT. UNTIL THIS TROUGH CROSSES...LOW LEVEL INSTABILITY WILL PROMOTE LINES OF SNOW SHOWERS MOVING PARALLEL TO THE UPPER FLOW. CAPE ACTUALLY INCREASES TONIGHT WITH THE TROUGH. THESE SNOW SHOWERS WILL BE MOSTLY NORTH OF HOULTON THROUGH THE EVENING BUT GUIDANCE SUGGEST A BAND COULD CROSS DOWN EAST LATE IN THE EVENING. LITTLE OR NO ACCUMULATION IS EXPECTED. THE PRIMARY CONCERNS WILL BE REDUCED VISIBILITY AND STRONG WIND GUSTS UP TO 40 MPH TONIGHT. THIS WILL CREATE HAZARDOUS CONDITIONS FOR MOTORISTS. THE CURRENT SPECIAL WEATHER STATEMENT FOR THE SNOW SHOWERS MAY NEED TO BE EXTENDED THROUGH THE EVENING. SOME SNOW SHOWERS COULD BE MORE PROLONGED THIS EVENING AS THE UPPER TROUGH CROSSES FOR NORTHERN AROOSTOOK. ONCE THE UPPER TROUGH PASSES...SKIES WILL CLEAR BUT WINDS WILL REMAIN VERY STRONG THROUGH SUNDAY MORNING. SUNDAY WILL FEATURE THE COLDEST HIGH TEMPERATURES OF THE MONTH TO DATE WITH READINGS IN THE LOW 20S NORTH AND UPPER 20S TO NEAR 30F FOR BANGOR AND DOWN EAST. WIND CHILLS SUNDAY MORNING WILL BE NEAR ZERO...A SIGNIFICANT CONTRAST TO RECENT DAYS. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... HIGH PRESSURE MOVING OFF THE EAST COAST SUNDAY NIGHT COMBINED WITH WEAK LOW PRESSURE APPROACHING FROM THE GREAT LAKES WILL BRING WARM ADVECTION TOWARD THE AREA ON MONDAY. SOME SPOTTY LIGHT SNOW WILL BE POSSIBLE ACROSS THE FAR NORTH SUNDAY NIGHT. SOME LIGHT PRECIPITATION IN THE FORM OF SNOW OVER THE NORTH AND LIGHT RAIN DOWNEAST WITH SOME SLEET AND FREEZING RAIN POSSIBLE IN CENTRAL AREAS WILL SPREAD ACROSS THE REGION MONDAY AS THE LOW MOVES IN. THE LOW WILL LIFT TO OUR NORTHWEST MONDAY NIGHT AND WEAKEN. SPOTTY LIGHT MIXED PRECIPITATION WILL BE POSSIBLE IN THE NORTH WITH RAIN SHOWERS OR DRIZZLE IN CENTRAL AND SOUTHERN AREAS. A WEAK WARM FRONTAL BOUNDARY WILL REMAIN OVER THE AREA TUESDAY BRINGING A CONTINUATION OF CLOUDY CONDITIONS WITH SOME SPOTTY RAIN SHOWERS POSSIBLE. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... HIGH PRESSURE OVER THE MARITIMES WILL BRIEFLY NUDGE OVER THE REGION TUESDAY NIGHT INTO WEDNESDAY BUT THE AIR WILL REMAIN MILD WITH LONGWAVE RIDGING ANCHORED OVER THE EAST. A LARGE STORM SYSTEM TRACKING ACROSS THE NORTH CENTRAL PART OF THE COUNTRY WILL APPROACH WEDNESDAY NIGHT INTO THURSDAY PULLING WARMER AIR INTO THE REGION AS THE SYSTEM LIFTS INTO SOUTHERN CANADA. SOME SHOWERS, FOG AND DRIZZLE WILL BE LIKELY WEDNESDAY NIGHT INTO THURSDAY WITH UNSEASONABLY WARM AIR ACROSS THE REGION. A COLD FRONT WILL COME THROUGH THURSDAY NIGHT. GUSTY WEST WINDS AND MODERATELY COOLER CONDITIONS WILL PREVAIL FOR CHRISTMAS DAY AS THE LOW TRACKS INTO THE NORTHERN PART OF EASTERN CANADA. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... NEAR TERM: SNOW SHOWERS WILL GENERATE THE RISK OF TEMPO LIFR CONDITIONS AND A LOT OF LOW LEVEL TURBULENCE THIS EVENING...MOSTLY FROM PQI NORTHWARD. OTHERWISE...VFR CONDITIONS ARE EXPECTED WITH VERY GUSTY NW WINDS UP TO 40 MPH. THE WINDS WILL FURTHER INCREASE TONIGHT AND CONTINUE INTO SUNDAY MORNING. THE WINDS WILL DECREASE SUNDAY AFTERNOON. SHORT TERM: CONDITIONS WILL LIKELY DROP TO MVFR IN STRATUS CLOUDS SUNDAY NIGHT THEN BE MVFR TO IFR MONDAY INTO MONDAY NIGHT IN LOW CLOUDS. MVFR CONDITIONS ARE LIKELY TUESDAY INTO TUESDAY NIGHT. CONDITIONS MAY IMPROVE TO VFR DOWNEAST LATE TUESDAY NIGHT. VFR CONDITIONS ARE LIKELY WEDNESDAY. A RETURN TO IFR IN LOW CLOUDS IS THEN EXPECTED WEDNESDAY NIGHT INTO THURSDAY IN LOW CLOUDS. && .MARINE... NEAR TERM: THE GALE IS STILL EXPECTED WITH WIND GUSTS INCREASING TOWARDS 40 KTS LATER TONIGHT INTO SUNDAY MORNING. SEAS ARE EXPECTED TO REACH AS HIGH AS 10 FEET. SHORT TERM: A GALE MAY BE NEEDED ON MONDAY FOR GUSTY WEST WINDS. AN SCA OR GALE WILL LIKELY BE NEEDED AGAIN CHRISTMAS EVE INTO CHRISTMAS DAY FOR STRONG GUSTY SOUTH WINDS BECOMING WESTERLY. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...GALE WARNING UNTIL 10 AM EST SUNDAY FOR ANZ050>052. && $$ NEAR TERM...VJN SHORT TERM...BLOOMER LONG TERM...BLOOMER AVIATION...VJN/BLOOMER MARINE...VJN/BLOOMER
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1201 PM EST FRI DEC 18 2015 .SYNOPSIS... LOW PRESSURE WILL EXIT ACROSS THE MARITIMES TODAY. ANOTHER LOW WILL MOVE UP FROM SOUTHEAST NEW ENGLAND THIS EVENING AND TRACK ACROSS SOUTHEAST NOVA SCOTIA EARLY SATURDAY MORNING. GUSTY NORTHWEST WINDS AND COLDER ON TAP FOR THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... A NEARLY STATIONARY FRONTAL BOUNDARY WILL REMAIN ACROSS THE GULF OF MAINE THIS AFTERNOON WHILE LOW PRESSURE MOVES NORTHEAST ALONG THE FRONT. EXPECT MOSTLY CLOUDY SKIES ACROSS THE FORECAST AREA THIS AFTERNOON. WILL ALSO HAVE A SLIGHT CHANCE OF RAIN/SNOW SHOWERS ACROSS NORTHERN AREAS...WITH A SLIGHT CHANCE OF RAIN SHOWERS ACROSS CENTRAL AREAS. BETTER RAIN SHOWER CHANCES WILL BEGIN TO DEVELOP ACROSS DOWNEAST AREAS THIS AFTERNOON WITH THE APPROACHING LOW. THE BEST SHOWER CHANCES WILL OCCUR LATER THIS AFTERNOON ALONG THE DOWNEAST COAST. HAVE UPDATED THE FORECAST TO ADJUST FOR CURRENT CONDITIONS ALONG WITH AFTERNOON TEMPERATURES...CLOUD COVER AND SHOWER CHANCES. PREVIOUS DISCUSSION... ANOTHER WAVE OF LOW PRES IS FORECAST TO MOVE UP ALONG THE FRONT LATER THIS AFTERNOON INTO TONIGHT. THE LOW IS FORECAST TO PASS ACROSS SE NOVA SCOTIA TONIGHT. THE HIGH RESOLUTION MODELS SUCH AS THE HRRR 3KM AND ARW SHOWING SOME MORE PRECIP MOVING NE W/THE BULK ACROSS EASTERN WASHINGTON COUNTY. THIS MATCHES UP WELL W/THE 00Z RUN OF THE NAM AND GFS AND EVEN THE CANADIAN GEM. DECIDED TO BOOST POPS UP INTO THE LIKELY CATEGORY(70%) LATER THIS AFTERNOON INTO TONIGHT ACROSS THE EASTERN 3RD OF THE CWA(WASHINGTON COUNTY). TEMPERATURES WILL BE WARM ENOUGH INITIALLY TO ALLOW FOR JUST RAIN, BUT AS DYNAMIC COOLING TAKES OVER THROUGH THE COLUMN AS SHOWN BY THE SOUNDINGS, RAIN WILL GO TO SOME SNOW BY THE EVENING. ATTM, ONLY EXPECTING MINOR ACCUMULATIONS OF WET SNOW. FURTHER N AND W, PRECIP CHANCES DROP OFF W/NW WINDS TAKING HOLD. CLOUDS WILL HANG ON MOST OF THE NIGHT KEEPING OVERNIGHT TEMPERATURES WELL ABOVE NORMAL. && .SHORT TERM /SATURDAY THROUGH SUNDAY/... GUSTY WEST WINDS CAN BE EXPECTED SATURDAY AS LOW PRESSURE EXITS THROUGH THE CANADIAN MARITIMES AND HIGH PRESSURE BEGINS TO BUILD IN FROM THE WEST. STEEPING LAPSE RATES SHOULD ALLOW FOR A FAIRLY DEEP MIXED LAYER WITH WIND GUSTS OF 25 TO 30 MPH POSSIBLE SATURDAY AFTERNOON. AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION DURING SATURDAY WITH SCATTERED SNOW SHOWERS EXPECTED ESPECIALLY ACROSS THE NORTH AND MOUNTAINS. HIGHS ON SATURDAY WILL RANGE FROM THE UPPER 20S TO NEAR 30 NORTH AND LOW TO MID 30S CENTRAL AND DOWN EAST. A FEW SNOW SHOWERS OR FLURRIES MAY LINGER INTO SATURDAY EVENING OTHERWISE EXPECT PARTLY TO MOSTLY CLOUDY SKIES. LOWS SATURDAY NIGHT ARE EXPECTED TO RANGE FROM THE MID TO UPPER TEENS NORTH AND LOW TO MID 20S DOWN EAST. SUNDAY WILL BE A MAINLY SUNNY DAY WITH NEAR SEASONAL TEMPERATURES EXPECTED AS HIGH PRESSURE BUILDS IN FROM THE SOUTH. HIGHS ON SUNDAY WILL RANGE FROM THE MID 20S NORTHERN AND THE UPPER 20S TO LOWER 30S DOWNEAST. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... HIGH PRESSURE WILL MOVE EAST OF THE MID ATLANTIC COAST SUNDAY NIGHT THROUGH MONDAY WITH A MODERATING TEMPERATURE TREND EXPECTED FOR EARLY NEXT WEEK. ALONG WITH THE MILDER AIR WILL COME THE CHANCE FOR A LITTLE LIGHT SNOW/RAIN DURING MONDAY AFTERNOON MAINLY NORTHERN AND CENTRAL AREAS. THE UNSEASONABLY MILD WEATHER IS EXPECTED TO PERSIST THROUGH MID WEEK AS HIGH PRESSURE REMAINS TO OUR EAST AND LOW PRESSURE REMAINS WELL TO OUR WEST. ANOTHER SYSTEM MAY APPROACH BY MID WEEK WITH THE CHANCE FOR RAIN. && .AVIATION /17Z FRIDAY THROUGH WEDNESDAY/... NEAR TERM: IFR/LIFR CONDITIONS ARE EXPECTED ACROSS NORTHERN PORTIONS OF THE FORECAST AREA THIS AFTERNOON THROUGH EARLY TONIGHT. MVFR/IFR CONDITIONS ARE EXPECTED DOWNEAST THIS AFTERNOON THROUGH EARLY TONIGHT. MVFR/VFR CONDITIONS ARE THEN EXPECTED ACROSS THE ENTIRE REGION LATER TONIGHT. SHORT TERM: VFR CONDITIONS EXPECTED EXCEPT WE COULD SEE MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SATURDAY AFTERNOON. GUSTY WEST WINDS CAN BE EXPECTED SATURDAY AND SATURDAY NIGHT THEN DECREASE BY SUNDAY. && .MARINE... NEAR TERM: A SMALL CRAFT ADVISORY MOSTLY FOR SEAS REMAINS IN EFFECT FOR MUCH OF THE WATERS...WITH THE EXCEPTION OF THE INTRACOASTAL WATERS...THIS AFTERNOON. SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED ACROSS ALL THE WATERS TONIGHT. VISIBILITIES WILL BE REDUCED IN RAIN OR SHOWERS AND PATCHY FOG THIS AFTERNOON THROUGH EARLY TONIGHT. SHORT TERM: WILL ISSUE A GALE WATCH FOR LATE SATURDAY THROUGH SUNDAY MORNING. THE POTENTIAL IS THERE TO SEE GUSTS GREATER THAN 35 KT WITH COLDER AIR COMING ACROSS WARM WATER. WIND/SEAS SHOULD THEN DECREASE LATER SUNDAY AFTERNOON BEFORE INCREASING AGAIN LATER SUNDAY NIGHT AND MONDAY. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...GALE WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING FOR ANZ050>052. SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR ANZ050- 051. && $$ NEAR TERM...NORCROSS/HEWITT SHORT TERM...DUDA LONG TERM...DUDA AVIATION...NORCROSS/DUDA MARINE...NORCROSS/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
851 AM EST FRI DEC 18 2015 .SYNOPSIS... LOW PRESSURE WILL EXIT ACROSS THE MARITIMES TODAY. ANOTHER LOW WILL MOVE UP FROM SOUTHEAST NEW ENGLAND THIS EVENING AND TRACK ACROSS SOUTHEAST NOVA SCOTIA EARLY SATURDAY MORNING. GUSTY NORTHWEST WINDS AND COLDER ON TAP FOR THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... HAVE UPDATED THE FORECAST TO INCLUDE A DENSE FOG ADVISORY UNTIL 11 AM ACROSS NORTHERN PORTIONS OF THE FORECAST AREA. PREVIOUS DISCUSSION... ANOTHER WAVE OF LOW PRES IS FORECAST TO MOVE UP ALONG THE FRONT LATER THIS AFTERNOON INTO TONIGHT. THE LOW IS FORECAST TO PASS ACROSS SE NOVA SCOTIA TONIGHT. THE HIGH RESOLUTION MODELS SUCH AS THE HRRR 3KM AND ARW SHOWING SOME MORE PRECIP MOVING NE W/THE BULK ACROSS EASTERN WASHINGTON COUNTY. THIS MATCHES UP WELL W/THE 00Z RUN OF THE NAM AND GFS AND EVEN THE CANADIAN GEM. DECIDED TO BOOST POPS UP INTO THE LIKELY CATEGORY(70%) LATER THIS AFTERNOON INTO TONIGHT ACROSS THE EASTERN 3RD OF THE CWA(WASHINGTON COUNTY). TEMPERATURES WILL BE WARM ENOUGH INITIALLY TO ALLOW FOR JUST RAIN, BUT AS DYNAMIC COOLING TAKES OVER THROUGH THE COLUMN AS SHOWN BY THE SOUNDINGS, RAIN WILL GO TO SOME SNOW BY THE EVENING. ATTM, ONLY EXPECTING MINOR ACCUMULATIONS OF WET SNOW. FURTHER N AND W, PRECIP CHANCES DROP OFF W/NW WINDS TAKING HOLD. CLOUDS WILL HANG ON MOST OF THE NIGHT KEEPING OVERNIGHT TEMPERATURES WELL ABOVE NORMAL. && .SHORT TERM /SATURDAY THROUGH SUNDAY/... GUSTY WEST WINDS CAN BE EXPECTED SATURDAY AS LOW PRESSURE EXITS THROUGH THE CANADIAN MARITIMES AND HIGH PRESSURE BEGINS TO BUILD IN FROM THE WEST. STEEPING LAPSE RATES SHOULD ALLOW FOR A FAIRLY DEEP MIXED LAYER WITH WIND GUSTS OF 25 TO 30 MPH POSSIBLE SATURDAY AFTERNOON. AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION DURING SATURDAY WITH SCATTERED SNOW SHOWERS EXPECTED ESPECIALLY ACROSS THE NORTH AND MOUNTAINS. HIGHS ON SATURDAY WILL RANGE FROM THE UPPER 20S TO NEAR 30 NORTH AND LOW TO MID 30S CENTRAL AND DOWN EAST. A FEW SNOW SHOWERS OR FLURRIES MAY LINGER INTO SATURDAY EVENING OTHERWISE EXPECT PARTLY TO MOSTLY CLOUDY SKIES. LOWS SATURDAY NIGHT ARE EXPECTED TO RANGE FROM THE MID TO UPPER TEENS NORTH AND LOW TO MID 20S DOWN EAST. SUNDAY WILL BE A MAINLY SUNNY DAY WITH NEAR SEASONAL TEMPERATURES EXPECTED AS HIGH PRESSURE BUILDS IN FROM THE SOUTH. HIGHS ON SUNDAY WILL RANGE FROM THE MID 20S NORTHERN AND THE UPPER 20S TO LOWER 30S DOWNEAST. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... HIGH PRESSURE WILL MOVE EAST OF THE MID ATLANTIC COAST SUNDAY NIGHT THROUGH MONDAY WITH A MODERATING TEMPERATURE TREND EXPECTED FOR EARLY NEXT WEEK. ALONG WITH THE MILDER AIR WILL COME THE CHANCE FOR A LITTLE LIGHT SNOW/RAIN DURING MONDAY AFTERNOON MAINLY NORTHERN AND CENTRAL AREAS. THE UNSEASONABLY MILD WEATHER IS EXPECTED TO PERSIST THROUGH MID WEEK AS HIGH PRESSURE REMAINS TO OUR EAST AND LOW PRESSURE REMAINS WELL TO OUR WEST. ANOTHER SYSTEM MAY APPROACH BY MID WEEK WITH THE CHANCE FOR RAIN. && .AVIATION /14Z FRIDAY THROUGH TUESDAY/... NEAR TERM: IFR TO VLIFR CONDITIONS ARE EXPECTED ACROSS NORTHERN PORTIONS OF THE FORECAST AREA THIS MORNING...WITH MVFR/IFR CONDITIONS THIS AFTERNOON. MVFR/IFR CONDITIONS ARE EXPECTED DOWNEAST THIS MORNING...WITH GENERALLY MVFR CONDITIONS THIS AFTERNOON. MVFR/VFR CONDITIONS ARE EXPECTED ACROSS THE ENTIRE REGION TONIGHT. SHORT TERM: VFR CONDITIONS EXPECTED EXCEPT WE COULD SEE MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SATURDAY AFTERNOON. GUSTY WEST WINDS CAN BE EXPECTED SATURDAY AND SATURDAY NIGHT THEN DECREASE BY SUNDAY. && .MARINE... NEAR TERM: SMALL CRAFT ADVISORY WILL REMAIN IN PLACE FOR THE OUTER WATERS THROUGH THE AFTERNOON. THE INTRACOASTAL ZONE HAS BEEN REMOVED FROM THE ADVISORY AS CONDITIONS HAVE IMPROVED. ANOTHER SURGE OF WINDS LATER THIS AFTERNOON INTO THE EVENING AS NW WINDS AND CAA HITS THE WATERS. DECIDED TO KEEP GUSTS AT 25 KT. SEAS WILL REMAIN NEAR SCA LEVELS ESPECIALLY FOR ANZ052(44027). SHORT TERM: WILL ISSUE A GALE WATCH FOR LATE SATURDAY THROUGH SUNDAY MORNING. THE POTENTIAL IS THERE TO SEE GUSTS GREATER THAN 35 KT WITH COLDER AIR COMING ACROSS WARM WATER. WIND/SEAS SHOULD THEN DECREASE LATER SUNDAY AFTERNOON BEFORE INCREASING AGAIN LATER SUNDAY NIGHT AND MONDAY. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR MEZ001>006. MARINE...GALE WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING FOR ANZ050>052. SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR ANZ050- 051. && $$ NEAR TERM...NORCROSS/HEWITT SHORT TERM...DUDA LONG TERM...DUDA AVIATION...NORCROSS/DUDA MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
659 AM EST FRI DEC 18 2015 .SYNOPSIS... LOW PRESSURE WILL EXIT ACROSS THE MARITIMES TODAY. ANOTHER LOW WILL MOVE UP FROM SOUTHEAST NEW ENGLAND THIS EVENING AND TRACK ACROSS SOUTHEAST NOVA SCOTIA EARLY SATURDAY MORNING. GUSTY NORTHWEST WINDS AND COLDER ON TAP FOR THE WEEKEND. && .NEAR TERM /TONIGHT/... 655 AM UPDATE: RADAR SHOWING SHOWERS PULLING AWAY AS LOW PRES EXITS ACROSS NOVA SCOTIA. IR SATELLITE IMAGERY SHOWED DRY SLOTTING THIS MORNING WHICH HAS ALLOWED FOG TO REDEVELOP AND BECOME DENSE IN SPOTS. DECIDED TO EXPAND THE FOG ACROSS THE ENTIRE CWA THROUGH AT LEAST MID MORNING. ONCE NW WINDS KICKS, BLYR SHOULD MIX TO ALLOW FOG TO LIFT W/IMPROVEMENT. UPDATED THE HAZARDOUS WEATHER OUTLOOK TO KEEP THE MENTION OF ICY SPOTS ON ROADS ACROSS THE NORTH AS TEMPS HOVERING RIGHT NEAR 32F IN SOME LOCALES. ANOTHER WAVE OF LOW PRES IS FORECAST TO MOVE UP ALONG THE FRONT LATER THIS AFTERNOON INTO TONIGHT. THE LOW IS FORECAST TO PASS ACROSS SE NOVA SCOTIA TONIGHT. THE HIGH RESOLUTION MODELS SUCH AS THE HRRR 3KM AND ARW SHOWING SOME MORE PRECIP MOVING NE W/THE BULK ACROSS EASTERN WASHINGTON COUNTY. THIS MATCHES UP WELL W/THE 00Z RUN OF THE NAM AND GFS AND EVEN THE CANADIAN GEM. DECIDED TO BOOST POPS UP INTO THE LIKELY CATEGORY(70%) LATER THIS AFTERNOON INTO TONIGHT ACROSS THE EASTERN 3RD OF THE CWA(WASHINGTON COUNTY). TEMPERATURES WILL BE WARM ENOUGH INITIALLY TO ALLOW FOR JUST RAIN, BUT AS DYNAMIC COOLING TAKES OVER THROUGH THE COLUMN AS SHOWN BY THE SOUNDINGS, RAIN WILL GO TO SOME SNOW BY THE EVENING. ATTM, ONLY EXPECTING MINOR ACCUMULATIONS OF WET SNOW. FURTHER N AND W, PRECIP CHANCES DROP OFF W/NW WINDS TAKING HOLD. CLOUDS WILL HANG ON MOST OF THE NIGHT KEEPING OVERNIGHT TEMPERATURES WELL ABOVE NORMAL. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/... GUSTY WEST WINDS CAN BE EXPECTED SATURDAY AS LOW PRESSURE EXITS THROUGH THE CANADIAN MARITIMES AND HIGH PRESSURE BEGINS TO BUILD IN FROM THE WEST. STEEPING LAPSE RATES SHOULD ALLOW FOR A FAIRLY DEEP MIXED LAYER WITH WIND GUSTS OF 25 TO 30 MPH POSSIBLE SATURDAY AFTERNOON. AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION DURING SATURDAY WITH SCATTERED SNOW SHOWERS EXPECTED ESPECIALLY ACROSS THE NORTH AND MOUNTAINS. HIGHS ON SATURDAY WILL RANGE FROM THE UPPER 20S TO NEAR 30 NORTH AND LOW TO MID 30S CENTRAL AND DOWN EAST. A FEW SNOW SHOWERS OR FLURRIES MAY LINGER INTO SATURDAY EVENING OTHERWISE EXPECT PARTLY TO MOSTLY CLOUDY SKIES. LOWS SATURDAY NIGHT ARE EXPECTED TO RANGE FROM THE MID TO UPPER TEENS NORTH AND LOW TO MID 20S DOWN EAST. SUNDAY WILL BE A MAINLY SUNNY DAY WITH NEAR SEASONAL TEMPERATURES EXPECTED AS HIGH PRESSURE BUILDS IN FROM THE SOUTH. HIGHS ON SUNDAY WILL RANGE FROM THE MID 20S NORTHERN AND THE UPPER 20S TO LOWER 30S DOWNEAST. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... HIGH PRESSURE WILL MOVE EAST OF THE MID ATLANTIC COAST SUNDAY NIGHT THROUGH MONDAY WITH A MODERATING TEMPERATURE TREND EXPECTED FOR EARLY NEXT WEEK. ALONG WITH THE MILDER AIR WILL COME THE CHANCE FOR A LITTLE LIGHT SNOW/RAIN DURING MONDAY AFTERNOON MAINLY NORTHERN AND CENTRAL AREAS. THE UNSEASONABLY MILD WEATHER IS EXPECTED TO PERSIST THROUGH MID WEEK AS HIGH PRESSURE REMAINS TO OUR EAST AND LOW PRESSURE REMAINS WELL TO OUR WEST. ANOTHER SYSTEM MAY APPROACH BY MID WEEK WITH THE CHANCE FOR RAIN. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... NEAR TERM: IFR W/PERIODS OF MVFR THIS MORNING FOR ALL TERMINALS. FOG WILL BE A NUISANCE FOR AIR TRAFFIC. CONDITIONS ARE EXPECTED TO IMPROVE TO MVFR THIS AFTERNOON FOR ALL TERMINALS AND THEN VFR TONIGHT. SHORT TERM: VFR CONDITIONS EXPECTED EXCEPT WE COULD SEE MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SATURDAY AFTERNOON. GUSTY WEST WINDS CAN BE EXPECTED SATURDAY AND SATURDAY NIGHT THEN DECREASE BY SUNDAY. && .MARINE... NEAR TERM: SMALL CRAFT ADVISORY WILL REMAIN IN PLACE FOR THE OUTER WATERS THROUGH THE AFTERNOON. THE INTRA COASTAL ZONE HAS BEEN REMOVED FROM THE ADVISORY AS CONDITIONS HAVE IMPROVED. ANOTHER SURGE OF WINDS LATER THIS AFTERNOON INTO THE EVENING AS NW WINDS AND CAA HITS THE WATERS. DECIDED TO KEEP GUSTS AT 25 KT. SEAS WILL REMAIN NEAR SCA LEVELS ESPECIALLY FOR ANZ052(44027). SHORT TERM: WILL ISSUE A GALE WATCH FOR LATE SATURDAY THROUGH SUNDAY MORNING. THE POTENTIAL IS THERE TO SEE GUSTS GREATER THAN 35 KT WITH COLDER AIR COMING ACROSS WARM WATER. WIND/SEAS SHOULD THEN DECREASE LATER SUNDAY AFTERNOON BEFORE INCREASING AGAIN LATER SUNDAY NIGHT AND MONDAY. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...GALE WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING FOR ANZ050>052. SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR ANZ050- 051. && $$ NEAR TERM...HEWITT SHORT TERM...DUDA LONG TERM...DUDA AVIATION...HEWITT/DUDA MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
419 AM EST FRI DEC 18 2015 .SYNOPSIS... LOW PRESSURE WILL EXIT ACROSS THE MARITIMES TODAY. ANOTHER LOW WILL MOVE UP FROM SOUTHEAST NEW ENGLAND THIS EVENING AND TRACK ACROSS SOUTHEAST NOVA SCOTIA EARLY SATURDAY MORNING. GUSTY NORTHWEST WINDS AND COLDER ON TAP FOR THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... RAIN WAS WINDING DOWN AND PULLING AWAY PER THE LATEST RADAR TRENDS. TEMPERATURES ACROSS THE REGION HAS SLOWLY WARMED ACROSS THE NORTHERN 1/2 OF THE CWA HELPING TO ALLEVIATE MOST OF THE ICING THREAT. SOME POCKETS OF ICING ON ROADS POSSIBLE BEFORE 8 AM ESPECIALLY IN THE LOW LYING LOCALES. TEMPERATURES ACROSS THE DOWNEAST AND COAST HAVE ACTUALLY COOLED DOWN INTO THE MID 40S AND STILL DROPPING AS NORTH WINDS HAVE BROUGHT SOME WEAK CAA INTO THAT REGION. TEMPERATURES ARE EXPECTED TO COOL DOWN TODAY ACROSS THE DOWNEAST AND COAST WHILE THE NORTHERN REGION COULD ACTUALLY WARM A FEW DEGREES BEFORE LEVELING OFF BY MIDDAY. AREAS OF FOG WILL BE A NUISANCE THIS MORNING. ANOTHER WAVE OF LOW PRES IS FORECAST TO MOVE UP ALONG THE FRONT LATER THIS AFTERNOON INTO TONIGHT. THE LOW IS FORECAST TO PASS ACROSS SE NOVA SCOTIA TONIGHT. THE HIGH RESOLUTION MODELS SUCH AS THE HRRR 3KM AND ARW SHOWING SOME MORE PRECIP MOVING NE W/THE BULK ACROSS EASTERN WASHINGTON COUNTY. THIS MATCHES UP WELL W/THE 00Z RUN OF THE NAM AND GFS AND EVEN THE CANADIAN GEM. DECIDED TO BOOST POPS UP INTO THE LIKELY CATEGORY(70%) LATER THIS AFTERNOON INTO TONIGHT ACROSS THE EASTERN 3RD OF THE CWA(WASHINGTON COUNTY). TEMPERATURES WILL BE WARM ENOUGH INITIALLY TO ALLOW FOR JUST RAIN, BUT AS DYNAMIC COOLING TAKES OVER THROUGH THE COLUMN AS SHOWN BY THE SOUNDINGS, RAIN WILL GO TO SOME SNOW BY THE EVENING. ATTM, ONLY EXPECTING MINOR ACCUMULATIONS OF WET SNOW. FURTHER N AND W, PRECIP CHANCES DROP OFF W/NW WINDS TAKING HOLD. CLOUDS WILL HANG ON MOST OF THE NIGHT KEEPING OVERNIGHT TEMPERATURES WELL ABOVE NORMAL. && .SHORT TERM /SATURDAY THROUGH SUNDAY/... GUSTY WEST WINDS CAN BE EXPECTED SATURDAY AS LOW PRESSURE EXITS THROUGH THE CANADIAN MARITIMES AND HIGH PRESSURE BEGINS TO BUILD IN FROM THE WEST. STEEPING LAPSE RATES SHOULD ALLOW FOR A FAIRLY DEEP MIXED LAYER WITH WIND GUSTS OF 25 TO 30 MPH POSSIBLE SATURDAY AFTERNOON. AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION DURING SATURDAY WITH SCATTERED SNOW SHOWERS EXPECTED ESPECIALLY ACROSS THE NORTH AND MOUNTAINS. HIGHS ON SATURDAY WILL RANGE FROM THE UPPER 20S TO NEAR 30 NORTH AND LOW TO MID 30S CENTRAL AND DOWN EAST. A FEW SNOW SHOWERS OR FLURRIES MAY LINGER INTO SATURDAY EVENING OTHERWISE EXPECT PARTLY TO MOSTLY CLOUDY SKIES. LOWS SATURDAY NIGHT ARE EXPECTED TO RANGE FROM THE MID TO UPPER TEENS NORTH AND LOW TO MID 20S DOWN EAST. SUNDAY WILL BE A MAINLY SUNNY DAY WITH NEAR SEASONAL TEMPERATURES EXPECTED AS HIGH PRESSURE BUILDS IN FROM THE SOUTH. HIGHS ON SUNDAY WILL RANGE FROM THE MID 20S NORTHERN AND THE UPPER 20S TO LOWER 30S DOWNEAST. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... HIGH PRESSURE WILL MOVE EAST OF THE MID ATLANTIC COAST SUNDAY NIGHT THROUGH MONDAY WITH A MODERATING TEMPERATURE TREND EXPECTED FOR EARLY NEXT WEEK. ALONG WITH THE MILDER AIR WILL COME THE CHANCE FOR A LITTLE LIGHT SNOW/RAIN DURING MONDAY AFTERNOON MAINLY NORTHERN AND CENTRAL AREAS. THE UNSEASONABLY MILD WEATHER IS EXPECTED TO PERSIST THROUGH MID WEEK AS HIGH PRESSURE REMAINS TO OUR EAST AND LOW PRESSURE REMAINS WELL TO OUR WEST. ANOTHER SYSTEM MAY APPROACH BY MID WEEK WITH THE CHANCE FOR RAIN. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... NEAR TERM: IFR W/PERIODS OF MVFR THIS MORNING FOR ALL TERMINALS. FOG WILL BE A NUISANCE FOR AIR TRAFFIC. CONDITIONS ARE EXPECTED TO IMPROVE TO MVFR THIS AFTERNOON FOR ALL TERMINALS AND THEN VFR TONIGHT. SHORT TERM: VFR CONDITIONS EXPECTED EXCEPT WE COULD SEE MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SATURDAY AFTERNOON. GUSTY WEST WINDS CAN BE EXPECTED SATURDAY AND SATURDAY NIGHT THEN DECREASE BY SUNDAY. && .MARINE... NEAR TERM: SMALL CRAFT ADVISORY WILL REMAIN IN PLACE FOR THE OUTER WATERS THROUGH THE AFTERNOON. THE INTRA COASTAL ZONE HAS BEEN REMOVED FROM THE ADVISORY AS CONDITIONS HAVE IMPROVED. ANOTHER SURGE OF WINDS LATER THIS AFTERNOON INTO THE EVENING AS NW WINDS AND CAA HITS THE WATERS. DECIDED TO KEEP GUSTS AT 25 KT. SEAS WILL REMAIN NEAR SCA LEVELS ESPECIALLY FOR ANZ052(44027). SHORT TERM: WILL ISSUE A GALE WATCH FOR LATE SATURDAY THROUGH SUNDAY MORNING. THE POTENTIAL IS THERE TO SEE GUSTS GREATER THAN 35 KT WITH COLDER AIR COMING ACROSS WARM WATER. WIND/SEAS SHOULD THEN DECREASE LATER SUNDAY AFTERNOON BEFORE INCREASING AGAIN LATER SUNDAY NIGHT AND MONDAY. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...GALE WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING FOR ANZ050>052. SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR ANZ050- 051. && $$ NEAR TERM...HEWITT SHORT TERM...DUDA LONG TERM...DUDA AVIATION...HEWITT/DUDA MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
341 PM EST FRI DEC 18 2015 .UPDATE... ISSUED AT 742 AM EST FRI DEC 18 2015 JUST A QUICK UPDATE TO THE FORECAST TO ADD LES ADVISORIES FOR BARAGA AND SOUTHERN HOUGHTON. ORIGINAL FORECAST HAD THEM ON THE EDGE FOR AN ADVISORY...BUT WITH REPORTS OF 13 INCHES IN CHASSELL AND 7 INCHES IN JACOBSVILLE FROM THE DOMINATE BAND...FELT THAT HAVING AN ADVISORY WAS GOOD AS IT DRIFTS SOUTH THROUGH THE DAY TODAY. THEN THEY SHOULD SEE ANOTHER 2-5 INCHES TONIGHT ONCE WINDS TURN TO THE NORTHWEST. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 404 AM EST FRI DEC 18 2015 LAKE EFFECT SNOW IS THE PRIMARY FOCUS FOR THE SHORT TERM FORECAST...ALTHOUGH STUBBORN CLOUDS AND -SHSN OR FLURRIES CONTINUE TO AFFECT MUCH OF THE REST OF THE AREA. A 991MB SURFACE LOW REMAINS NEARLY STATIONARY OVER FAR NORTHERN ONTARIO THIS MORNING WHICH IS HELPING TO KEEP THE GENERALLY WESTERLY WINDS ACROSS LAKE SUPERIOR. THAT WESTERLY FLOW IS COMBINING WITH A SECONDARY UPPER TROUGH MOVING THROUGH WESTERN LAKE SUPERIOR AND THE ABUNDANT MOISTURE WITH IT...ALONG WITH RAP ANALYSIS 850MB TEMPS OF -12 TO -15C TO PRODUCE LAKE EFFECT SNOW IN THE WEST TO WEST- SOUTHWEST WINDS SNOW BELTS. BEFORE GETTING INTO THE LAKE EFFECT ASPECT...DID WANT TO MENTION THAT WILL SHOW LIGHT SNOW SHOWERS OVER THE INLAND AREAS THIS MORNING AND TAPERING OFF TO FLURRIES THROUGH THE REST OF THE DAY BASED OFF UPSTREAM OBS AND RADAR IN WISCONSIN AND MINNESOTA. BACK TO THE LAKE EFFECT...HAVE BEEN PICKING UP DECENT RETURNS OVER FAR NORTHERN ONTONAGON COUNTY AND PORTIONS OF NORTHERN HOUGHTON COUNTY THROUGH THE NIGHT (GENERALLY BETWEEN 6-8KFT) AND EXPECT THERE TO BE MODERATE TO HEAVY LES OCCURRING IN THOSE AREAS. LOOKING AT A WEBCAM IN ONTONAGON...ONLY LOOKS LIKE AN INCH OR SO HAS FALLEN THERE WITH THE HEAVIEST OCCURRING A FEW MILES FARTHER NORTH. WEBCAMS FARTHER INLAND AT TWIN LAKES ONLY SHOWS LIMITED ACCUMULATIONS THUS FAR...SO NOT ENTIRELY SURE HOW MUCH HAS FALLEN UNDER THAT HEAVIER BAND. FARTHER NORTH...WEBCAMS SHOW A SIMILAR STORY...WITH THE KRC CAM SHOWING LITTLE ADDITIONAL ACCUMULATION SINCE 1AM BUT CAMERAS IN HOUGHTON HAVE SHOWN HEAVY SNOW AT TIMES. WILL BE CURIOUS TO SEE SOME REPORTS IN THE MORNING...BUT WONDERING IF THE TRANSIENT NATURE OF THE LES WILL KEEP THE HEAVIER AMOUNTS ISOLATED. A POCKET OF DEEPER MOISTURE WITH THE SHORTWAVE MOVES THROUGH THIS MORNING AND ANOTHER AREA OF DEEP MOISTURE SLIDES THROUGH TONIGHT. THAT KEEPS INVERSION HEIGHTS UP AROUND 8-10KFT OVER THE WEST THIS MORNING...BUT SHOULD SLOWLY LOWER THIS AFTERNOON INTO TONIGHT AS THE AREA SEES INCREASING SUBSIDENCE FROM THE APPROACHING RIDGE OVER MINNESOTA. OVER THE EAST...THE INCREASED LAKE MODIFICATION AND LATER ARRIVAL OF THE APPROACHING RIDGE SHOULD KEEP INVERSION HEIGHTS IN THE 9-10KFT RANGE FOR MUCH OF THE NIGHT. WITH THE FAVORABLE LAKE EFFECT CONDITIONS...LOCATIONS AND AMOUNTS LARGELY DEPEND ON THE WINDS. TWO SURFACE TROUGHS WILL BE GRADUALLY SHIFTING WINDS THROUGH THE SHORT TERM PERIOD. THE FIRST WILL SLIDE THROUGH THIS MORNING AND SLOWLY SHIFT THE WINDS A LITTLE MORE WEST TO EVEN WEST-NORTHWEST OVER THE KEWEENAW PENINSULA. THAT SHOULD LEAD TO THE DOMINATE BAND (THAT HAS BEEN LOCATED FROM JUST NORTH OF THE APOSTLE ISLANDS AND THROUGH NORTHERN HOUGHTON COUNTY) TO SLOWLY SLIDE SOUTH WITH MORE WIDESPREAD WIND PARALLEL BANDS IMPACT THE REST OF THE KEWEENAW PENINSULA. WHILE THIS WIND SHIFT WILL PUSH THE LAKE EFFECT SNOW FARTHER SOUTH OVER EASTERN LAKE SUPERIOR...DON/T THINK THAT MUCH WILL BE IMPACTING THE EASTERN U.P. UNTIL THE SECONDARY TROUGH PUSHES THROUGH THIS EVENING AND SHIFTS THE WINDS TO THE NORTHWEST ACROSS LAKE SUPERIOR. THAT WILL FINALLY LEAD TO SOME LAKE EFFECT OVER THE EASTERN CWA...PRIMARILY EASTERN ALGER...NORTHERN SCHOOLCRAFT...AND LUCE COUNTIES. HIGH RESOLUTION MODELS ALL AGREE ON THAT IDEA...WITH A BURST OF MODERATE TO HEAVY SNOW TO OCCUR INITIALLY IN THE EVENING (LARGELY BETWEEN 00-03Z) NEAR THE LAKE SUPERIOR SHORELINE AS THE DOMINATE BAND SLIDES SOUTH BEFORE TRANSITIONING TO WIND PARALLEL BANDS FOR THE REST OF THE NIGHT AND INTO SATURDAY. WITH SOME INDICATIONS OF A LAND BREEZE OVER THE NORTH CENTRAL U.P. INCREASING CONVERGENCE...WOULD EXPECT THERE TO BE A STRONGER BAND SOMEWHERE BETWEEN MUNISING AND GRAND MARAIS AND LIKELY AFFECTING THE PICTURED ROCKS NATIONAL LAKE SHORE. WITH THAT EXPECTATION...BELIEVE SOME LOCATIONS SHOULD SEE THE 4IN/12HR CRITERIA FOR THE EASTERN AREAS AND WILL ISSUES A LAKE EFFECT SNOW ADVISORY FOR ALGER/LUCE AND NORTHERN SCHOOLCRAFT STARTING AT 00Z AND CONTINUING INTO SATURDAY. INTENSITY SHOULD REALLY DIMINISH LATE INTO THE NIGHT AND INTO SATURDAY AS INVERSION HEIGHTS ARE CUT IN HALF. AS FOR THE REST OF THE HEADLINES...HAVE LEFT THE EXISTING WARNING/ADVISORIES IN PLACE OVER THE WEST AND WHILE KEWEENAW COUNTY WILL LIKELY ONLY SEE ADVISORY SNOWFALL THE REST OF THE WAY...DON/T WANT TO ADJUST THE HEADLINE UNTIL WE START SEEING REPORTS. GOGEBIC IS THE MAIN QUESTION MARK...SINCE INVERSION HEIGHTS WILL BE FALLING AS THE WINDS FINALLY TURN MORE FAVORABLE TONIGHT. THOSE LOWERING INVERSION HEIGHTS WILL LIMIT THE INTENSITY BUT ALSO PUT THE ENTIRE CLOUD WITHIN THE DGZ AND LEAD TO FAIRLY FLUFFY SNOW. SINCE THE FORECAST ONLY HAS MARGINAL ADVISORY SNOW MAINLY NORTH OF THE POPULATION AREAS IN WESTERN GOGEBIC COUNTY...WILL NOT ISSUE AN ADVISORY FOR THEM AT THIS TIME. FINALLY...WILL BE A FAIRLY COLD DAY TODAY (AT LEAST WHEN COMPARED TO WHAT WE HAVE BEEN SEEING SO FAR THIS WINTER) WITH HIGHS IN THE UPPER TEENS OVER THE WEST AND THE LOW-MID 20S OVER THE EAST. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 336 AM EST FRI DEC 18 2015 NAM SHOWS A 500 MB TROUGH ON THE WEST COAST...A RIDGE OVER THE ROCKIES INTO THE PLAINS AND TROUGHING INTO THE ERN U.S. 12Z SAT. UPPER RIDGING THEN MOVES INTO THE UPPER GREAT LAKES ON SAT INTO SUN. ANOTHER SHORTWAVE MOVES INTO THE UPPER GREAT LAKES ON SUN NIGHT. LAKE EFFECT SNOW WINDS DOWN SAT MORNING AS INVERSION HEIGHTS FALL THROUGHOUT THE DAY AND STARTS SLOWLY WARMING ALOFT AND WINDS BACK TO THE WSW LATE. NEXT SYSTEM STARTS TO ARRIVE SUN AFTERNOON AND HAVE SLIGHT CHANCE POPS IN FOR THEN AND CHANCE POPS IN FOR SUN NIGHT WITH LIKELY POPS FOR THE EAST LATE SUN NIGHT. COULD BE SOME RAIN MIXED IN WITH THE SNOW FOR THE FAR SOUTH AND EAST FOR SUN NIGHT. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR TEMPERATURES. IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH ACROSS MOST OF THE U.S. WITH A SHORTWAVE IN THE UPPER GREAT LAKES 12Z MON. THERE IS ANOTHER SHORTWAVE OVER THE NORTHERN ROCKIES 12Z MON THAT MOVES INTO THE NORTHERN PLAINS 12Z TUE. MORE TROUGHING COMES INTO THE NORTHERN PLAINS 12Z WED AND THIS MOVES INTO THE UPPER GREAT LAKES WED NIGHT INTO THU. HAVE CHANCE POPS IN FOR MON AND THEN MOISTURE IS LIMITED UNTIL NEXT SYSTEM ARRIVES FOR TUE NIGHT AND WED WITH CHANCE POPS AGAIN. TEMPERATURES LOOK TO STAY ABOVE NORMAL FOR THIS FORECAST PERIOD AND PCPN WILL BE SNOW MIXED WITH RAIN. RAIN WILL BE CONFINED TO MAINLY ALONG LAKE MICHIGAN AND THE EAST HALF OF THE CWA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1253 PM EST FRI DEC 18 2015 CMX CONTINUES TO THE AIRPORT OF CONCERN THROUGH THE PERIOD...WITH VIS FLUCTUATING BETWEEN LIFR AND MVFR...AND CEILINGS MAINLY VFR TO HIGH END MVFR AS BANDS OF LAKE EFFECT SNOW SHOWERS MOVE NEAR THE SITE. WINDS WILL STAY MAINLY OUT OF THE 280-300 DEGREE RANGE... PLENTY OF MOISTURE STILL PUMPING INTO THE AREA AND WINDS GUSTING TO AROUND 25KTS...EXPECT NO SIGNIFICANT IMPROVEMENT THROUGH AT LEAST 15Z SATURDAY. INDICATIONS ARE THAT THE MOISTURE WILL BEGIN TO DIMINISH SATURDAY AS A RIDGE OF HIGH PRESSURE EXTENDING ACROSS MUCH OF MN AT DAYBREAK BUILDS INTO FAR W UPPER MI. THIS SHOULD BE ENOUGH TO SCATTER OUT THE CEILING AT IWD BY LATE MORNING....WITH W WINDS GUSTING STILL TO AROUND 20KTS. THE GUSTY CONDITIONS AND VFR TO HIGH END MVFR CEILINGS WILL ALSO REMAIN AT SAW THROUGH THE PERIOD. THE MAIN CONCERN THERE IS THAT IT WILL BE ON THE EDGE OF SNOW SHOWERS FROM THE W AND E. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 341 PM EST FRI DEC 18 2015 W-NW GALES OF 35 TO 40KTS CONTINUE...DIMINISHING W TO E THROUGU THE DAY SATURDAY. LOW PRESSURE NEAR JAMES BAY WILL PUSH A PAIR OF WEAK TROUGHS ACROSS LAKE SUPERIOR THROUGH SATURDAY MORNING...AS IT IS MERGES WITH A STRONGER LOW OVER QUEBEC. A RIDGE EXTENDING FROM HIGH PRESSURE CENTERED IN THE SE U.S. WILL CROSS THE UPPER GREAT LAKES SATURDAY AFTERNOON AND EVENING...BRIEFLY BRINGING GUSTS BACK TO AROUND 20KTS. A ORGANIZING IN THE CENTRAL PLAINS SATURDAY NIGHT WILL TRACK NE ON SUNDAY...CROSSING THE UPPER GREAT LAKES SUNDAY NIGHT AND MONDAY MORNING. EXPECT WINDS TO GUST OF 25-30KTS SUNDAY...AND AGAIN MONDAY. A WEAK RIDGE WILL CROSS LAKE SUPERIOR MONDAY NIGHT. EXPECT BROAD LOW PRESSURE DEVELOPING OVER THE N AND CENTRAL PLAINS ON TUESDAY TO MOVE INTO THE UPPER MS VALLEY ON WEDNESDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW WARNING UNTIL 7 AM EST SATURDAY FOR MIZ001-003. LAKE EFFECT SNOW ADVISORY UNTIL 2 PM EST SATURDAY FOR MIZ006-007- 085. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ002-004- 084. LAKE SUPERIOR... GALE WARNING UNTIL 1 PM EST SATURDAY FOR LSZ264>267. GALE WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY FOR LSZ162-263. GALE WARNING UNTIL 11 AM EST SATURDAY FOR LSZ244-245. GALE WARNING UNTIL 5 AM EST /4 AM CST/ SATURDAY FOR LSZ240>243. LAKE MICHIGAN... NONE. && $$ UPDATE...SRF SHORT TERM...SRF LONG TERM...07 AVIATION...KF MARINE...- NONE -
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1254 PM EST FRI DEC 18 2015 .UPDATE... ISSUED AT 742 AM EST FRI DEC 18 2015 JUST A QUICK UPDATE TO THE FORECAST TO ADD LES ADVISORIES FOR BARAGA AND SOUTHERN HOUGHTON. ORIGINAL FORECAST HAD THEM ON THE EDGE FOR AN ADVISORY...BUT WITH REPORTS OF 13 INCHES IN CHASSELL AND 7 INCHES IN JACOBSVILLE FROM THE DOMINATE BAND...FELT THAT HAVING AN ADVISORY WAS GOOD AS IT DRIFTS SOUTH THROUGH THE DAY TODAY. THEN THEY SHOULD SEE ANOTHER 2-5 INCHES TONIGHT ONCE WINDS TURN TO THE NORTHWEST. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 404 AM EST FRI DEC 18 2015 LAKE EFFECT SNOW IS THE PRIMARY FOCUS FOR THE SHORT TERM FORECAST...ALTHOUGH STUBBORN CLOUDS AND -SHSN OR FLURRIES CONTINUE TO AFFECT MUCH OF THE REST OF THE AREA. A 991MB SURFACE LOW REMAINS NEARLY STATIONARY OVER FAR NORTHERN ONTARIO THIS MORNING WHICH IS HELPING TO KEEP THE GENERALLY WESTERLY WINDS ACROSS LAKE SUPERIOR. THAT WESTERLY FLOW IS COMBINING WITH A SECONDARY UPPER TROUGH MOVING THROUGH WESTERN LAKE SUPERIOR AND THE ABUNDANT MOISTURE WITH IT...ALONG WITH RAP ANALYSIS 850MB TEMPS OF -12 TO -15C TO PRODUCE LAKE EFFECT SNOW IN THE WEST TO WEST- SOUTHWEST WINDS SNOW BELTS. BEFORE GETTING INTO THE LAKE EFFECT ASPECT...DID WANT TO MENTION THAT WILL SHOW LIGHT SNOW SHOWERS OVER THE INLAND AREAS THIS MORNING AND TAPERING OFF TO FLURRIES THROUGH THE REST OF THE DAY BASED OFF UPSTREAM OBS AND RADAR IN WISCONSIN AND MINNESOTA. BACK TO THE LAKE EFFECT...HAVE BEEN PICKING UP DECENT RETURNS OVER FAR NORTHERN ONTONAGON COUNTY AND PORTIONS OF NORTHERN HOUGHTON COUNTY THROUGH THE NIGHT (GENERALLY BETWEEN 6-8KFT) AND EXPECT THERE TO BE MODERATE TO HEAVY LES OCCURRING IN THOSE AREAS. LOOKING AT A WEBCAM IN ONTONAGON...ONLY LOOKS LIKE AN INCH OR SO HAS FALLEN THERE WITH THE HEAVIEST OCCURRING A FEW MILES FARTHER NORTH. WEBCAMS FARTHER INLAND AT TWIN LAKES ONLY SHOWS LIMITED ACCUMULATIONS THUS FAR...SO NOT ENTIRELY SURE HOW MUCH HAS FALLEN UNDER THAT HEAVIER BAND. FARTHER NORTH...WEBCAMS SHOW A SIMILAR STORY...WITH THE KRC CAM SHOWING LITTLE ADDITIONAL ACCUMULATION SINCE 1AM BUT CAMERAS IN HOUGHTON HAVE SHOWN HEAVY SNOW AT TIMES. WILL BE CURIOUS TO SEE SOME REPORTS IN THE MORNING...BUT WONDERING IF THE TRANSIENT NATURE OF THE LES WILL KEEP THE HEAVIER AMOUNTS ISOLATED. A POCKET OF DEEPER MOISTURE WITH THE SHORTWAVE MOVES THROUGH THIS MORNING AND ANOTHER AREA OF DEEP MOISTURE SLIDES THROUGH TONIGHT. THAT KEEPS INVERSION HEIGHTS UP AROUND 8-10KFT OVER THE WEST THIS MORNING...BUT SHOULD SLOWLY LOWER THIS AFTERNOON INTO TONIGHT AS THE AREA SEES INCREASING SUBSIDENCE FROM THE APPROACHING RIDGE OVER MINNESOTA. OVER THE EAST...THE INCREASED LAKE MODIFICATION AND LATER ARRIVAL OF THE APPROACHING RIDGE SHOULD KEEP INVERSION HEIGHTS IN THE 9-10KFT RANGE FOR MUCH OF THE NIGHT. WITH THE FAVORABLE LAKE EFFECT CONDITIONS...LOCATIONS AND AMOUNTS LARGELY DEPEND ON THE WINDS. TWO SURFACE TROUGHS WILL BE GRADUALLY SHIFTING WINDS THROUGH THE SHORT TERM PERIOD. THE FIRST WILL SLIDE THROUGH THIS MORNING AND SLOWLY SHIFT THE WINDS A LITTLE MORE WEST TO EVEN WEST-NORTHWEST OVER THE KEWEENAW PENINSULA. THAT SHOULD LEAD TO THE DOMINATE BAND (THAT HAS BEEN LOCATED FROM JUST NORTH OF THE APOSTLE ISLANDS AND THROUGH NORTHERN HOUGHTON COUNTY) TO SLOWLY SLIDE SOUTH WITH MORE WIDESPREAD WIND PARALLEL BANDS IMPACT THE REST OF THE KEWEENAW PENINSULA. WHILE THIS WIND SHIFT WILL PUSH THE LAKE EFFECT SNOW FARTHER SOUTH OVER EASTERN LAKE SUPERIOR...DON/T THINK THAT MUCH WILL BE IMPACTING THE EASTERN U.P. UNTIL THE SECONDARY TROUGH PUSHES THROUGH THIS EVENING AND SHIFTS THE WINDS TO THE NORTHWEST ACROSS LAKE SUPERIOR. THAT WILL FINALLY LEAD TO SOME LAKE EFFECT OVER THE EASTERN CWA...PRIMARILY EASTERN ALGER...NORTHERN SCHOOLCRAFT...AND LUCE COUNTIES. HIGH RESOLUTION MODELS ALL AGREE ON THAT IDEA...WITH A BURST OF MODERATE TO HEAVY SNOW TO OCCUR INITIALLY IN THE EVENING (LARGELY BETWEEN 00-03Z) NEAR THE LAKE SUPERIOR SHORELINE AS THE DOMINATE BAND SLIDES SOUTH BEFORE TRANSITIONING TO WIND PARALLEL BANDS FOR THE REST OF THE NIGHT AND INTO SATURDAY. WITH SOME INDICATIONS OF A LAND BREEZE OVER THE NORTH CENTRAL U.P. INCREASING CONVERGENCE...WOULD EXPECT THERE TO BE A STRONGER BAND SOMEWHERE BETWEEN MUNISING AND GRAND MARAIS AND LIKELY AFFECTING THE PICTURED ROCKS NATIONAL LAKE SHORE. WITH THAT EXPECTATION...BELIEVE SOME LOCATIONS SHOULD SEE THE 4IN/12HR CRITERIA FOR THE EASTERN AREAS AND WILL ISSUES A LAKE EFFECT SNOW ADVISORY FOR ALGER/LUCE AND NORTHERN SCHOOLCRAFT STARTING AT 00Z AND CONTINUING INTO SATURDAY. INTENSITY SHOULD REALLY DIMINISH LATE INTO THE NIGHT AND INTO SATURDAY AS INVERSION HEIGHTS ARE CUT IN HALF. AS FOR THE REST OF THE HEADLINES...HAVE LEFT THE EXISTING WARNING/ADVISORIES IN PLACE OVER THE WEST AND WHILE KEWEENAW COUNTY WILL LIKELY ONLY SEE ADVISORY SNOWFALL THE REST OF THE WAY...DON/T WANT TO ADJUST THE HEADLINE UNTIL WE START SEEING REPORTS. GOGEBIC IS THE MAIN QUESTION MARK...SINCE INVERSION HEIGHTS WILL BE FALLING AS THE WINDS FINALLY TURN MORE FAVORABLE TONIGHT. THOSE LOWERING INVERSION HEIGHTS WILL LIMIT THE INTENSITY BUT ALSO PUT THE ENTIRE CLOUD WITHIN THE DGZ AND LEAD TO FAIRLY FLUFFY SNOW. SINCE THE FORECAST ONLY HAS MARGINAL ADVISORY SNOW MAINLY NORTH OF THE POPULATION AREAS IN WESTERN GOGEBIC COUNTY...WILL NOT ISSUE AN ADVISORY FOR THEM AT THIS TIME. FINALLY...WILL BE A FAIRLY COLD DAY TODAY (AT LEAST WHEN COMPARED TO WHAT WE HAVE BEEN SEEING SO FAR THIS WINTER) WITH HIGHS IN THE UPPER TEENS OVER THE WEST AND THE LOW-MID 20S OVER THE EAST. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 336 AM EST FRI DEC 18 2015 NAM SHOWS A 500 MB TROUGH ON THE WEST COAST...A RIDGE OVER THE ROCKIES INTO THE PLAINS AND TROUGHING INTO THE ERN U.S. 12Z SAT. UPPER RIDGING THEN MOVES INTO THE UPPER GREAT LAKES ON SAT INTO SUN. ANOTHER SHORTWAVE MOVES INTO THE UPPER GREAT LAKES ON SUN NIGHT. LAKE EFFECT SNOW WINDS DOWN SAT MORNING AS INVERSION HEIGHTS FALL THROUGHOUT THE DAY AND STARTS SLOWLY WARMING ALOFT AND WINDS BACK TO THE WSW LATE. NEXT SYSTEM STARTS TO ARRIVE SUN AFTERNOON AND HAVE SLIGHT CHANCE POPS IN FOR THEN AND CHANCE POPS IN FOR SUN NIGHT WITH LIKELY POPS FOR THE EAST LATE SUN NIGHT. COULD BE SOME RAIN MIXED IN WITH THE SNOW FOR THE FAR SOUTH AND EAST FOR SUN NIGHT. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR TEMPERATURES. IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH ACROSS MOST OF THE U.S. WITH A SHORTWAVE IN THE UPPER GREAT LAKES 12Z MON. THERE IS ANOTHER SHORTWAVE OVER THE NORTHERN ROCKIES 12Z MON THAT MOVES INTO THE NORTHERN PLAINS 12Z TUE. MORE TROUGHING COMES INTO THE NORTHERN PLAINS 12Z WED AND THIS MOVES INTO THE UPPER GREAT LAKES WED NIGHT INTO THU. HAVE CHANCE POPS IN FOR MON AND THEN MOISTURE IS LIMITED UNTIL NEXT SYSTEM ARRIVES FOR TUE NIGHT AND WED WITH CHANCE POPS AGAIN. TEMPERATURES LOOK TO STAY ABOVE NORMAL FOR THIS FORECAST PERIOD AND PCPN WILL BE SNOW MIXED WITH RAIN. RAIN WILL BE CONFINED TO MAINLY ALONG LAKE MICHIGAN AND THE EAST HALF OF THE CWA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1253 PM EST FRI DEC 18 2015 CMX CONTINUES TO THE AIRPORT OF CONCERN THROUGH THE PERIOD...WITH VIS FLUCTUATING BETWEEN LIFR AND MVFR...AND CEILINGS MAINLY VFR TO HIGH END MVFR AS BANDS OF LAKE EFFECT SNOW SHOWERS MOVE NEAR THE SITE. WINDS WILL STAY MAINLY OUT OF THE 280-300 DEGREE RANGE... PLENTY OF MOISTURE STILL PUMPING INTO THE AREA AND WINDS GUSTING TO AROUND 25KTS...EXPECT NO SIGNIFICANT IMPROVEMENT THROUGH AT LEAST 15Z SATURDAY. INDICATIONS ARE THAT THE MOISTURE WILL BEGIN TO DIMINISH SATURDAY AS A RIDGE OF HIGH PRESSURE EXTENDING ACROSS MUCH OF MN AT DAYBREAK BUILDS INTO FAR W UPPER MI. THIS SHOULD BE ENOUGH TO SCATTER OUT THE CEILING AT IWD BY LATE MORNING....WITH W WINDS GUSTING STILL TO AROUND 20KTS. THE GUSTY CONDITIONS AND VFR TO HIGH END MVFR CEILINGS WILL ALSO REMAIN AT SAW THROUGH THE PERIOD. THE MAIN CONCERN THERE IS THAT IT WILL BE ON THE EDGE OF SNOW SHOWERS FROM THE W AND E. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 404 AM EST FRI DEC 18 2015 A NEARLY STATIONARY LOW OVER FAR NORTHERN ONTARIO WILL CONTINUE TO PRODUCE WESTERLY GALES TODAY BEFORE A TROUGH SHIFTS WINDS TO THE NORTHWEST TONIGHT. THE CURRENT GALE WARNINGS LOOK TO BE IN GOOD SHAPE WITH THEM ENDING FROM WEST TO EAST LATE TONIGHT THROUGH SATURDAY AS A SURFACE RIDGE SLIDES THROUGH THE AREA. THAT SURFACE RIDGE WILL ONLY BRIEFLY DROP WINDS BELOW 20KTS...BEFORE SOUTHEASTERLY WINDS INCREASE ON SUNDAY AHEAD OF A LOW PRESSURE SYSTEM THAT WILL MOVE THROUGH THE UPPER GREAT LAKES REGION MONDAY MORNING. AS THAT LOW MOVES THROUGH...EXPECT WINDS TO BACK TO THE NORTH-NORTHWEST AND LEAD TO GUSTS TO 30KTS AT TIMES MONDAY AFTERNOON INTO MONDAY EVENING. FINALLY...WITH THE COLD AIR OVER THE WESTERN LAKE...DO HAVE SOME FREEZING SPRAY IN THE FORECAST FOR TODAY INTO SATURDAY MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW WARNING UNTIL 7 AM EST SATURDAY FOR MIZ001-003. LAKE EFFECT SNOW ADVISORY FROM 6 PM THIS EVENING TO 2 PM EST SATURDAY FOR MIZ006-007-085. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ002-004- 084. LAKE SUPERIOR... GALE WARNING UNTIL 1 PM EST SATURDAY FOR LSZ264>267. GALE WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY FOR LSZ162-263. GALE WARNING UNTIL 11 AM EST SATURDAY FOR LSZ244-245. GALE WARNING UNTIL 5 AM EST /4 AM CST/ SATURDAY FOR LSZ240>243. LAKE MICHIGAN... NONE. && $$ UPDATE...SRF SHORT TERM...SRF LONG TERM...07 AVIATION...KF MARINE...SRF
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
743 AM EST FRI DEC 18 2015 .UPDATE... ISSUED AT 742 AM EST FRI DEC 18 2015 JUST A QUICK UPDATE TO THE FORECAST TO ADD LES ADVISORIES FOR BARAGA AND SOUTHERN HOUGHTON. ORIGINAL FORECAST HAD THEM ON THE EDGE FOR AN ADVISORY...BUT WITH REPORTS OF 13 INCHES IN CHASSELL AND 7 INCHES IN JACOBSVILLE FROM THE DOMINATE BAND...FELT THAT HAVING AN ADVISORY WAS GOOD AS IT DRIFTS SOUTH THROUGH THE DAY TODAY. THEN THEY SHOULD SEE ANOTHER 2-5 INCHES TONIGHT ONCE WINDS TURN TO THE NORTHWEST. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 404 AM EST FRI DEC 18 2015 LAKE EFFECT SNOW IS THE PRIMARY FOCUS FOR THE SHORT TERM FORECAST...ALTHOUGH STUBBORN CLOUDS AND -SHSN OR FLURRIES CONTINUE TO AFFECT MUCH OF THE REST OF THE AREA. A 991MB SURFACE LOW REMAINS NEARLY STATIONARY OVER FAR NORTHERN ONTARIO THIS MORNING WHICH IS HELPING TO KEEP THE GENERALLY WESTERLY WINDS ACROSS LAKE SUPERIOR. THAT WESTERLY FLOW IS COMBINING WITH A SECONDARY UPPER TROUGH MOVING THROUGH WESTERN LAKE SUPERIOR AND THE ABUNDANT MOISTURE WITH IT...ALONG WITH RAP ANALYSIS 850MB TEMPS OF -12 TO -15C TO PRODUCE LAKE EFFECT SNOW IN THE WEST TO WEST- SOUTHWEST WINDS SNOW BELTS. BEFORE GETTING INTO THE LAKE EFFECT ASPECT...DID WANT TO MENTION THAT WILL SHOW LIGHT SNOW SHOWERS OVER THE INLAND AREAS THIS MORNING AND TAPERING OFF TO FLURRIES THROUGH THE REST OF THE DAY BASED OFF UPSTREAM OBS AND RADAR IN WISCONSIN AND MINNESOTA. BACK TO THE LAKE EFFECT...HAVE BEEN PICKING UP DECENT RETURNS OVER FAR NORTHERN ONTONAGON COUNTY AND PORTIONS OF NORTHERN HOUGHTON COUNTY THROUGH THE NIGHT (GENERALLY BETWEEN 6-8KFT) AND EXPECT THERE TO BE MODERATE TO HEAVY LES OCCURRING IN THOSE AREAS. LOOKING AT A WEBCAM IN ONTONAGON...ONLY LOOKS LIKE AN INCH OR SO HAS FALLEN THERE WITH THE HEAVIEST OCCURRING A FEW MILES FARTHER NORTH. WEBCAMS FARTHER INLAND AT TWIN LAKES ONLY SHOWS LIMITED ACCUMULATIONS THUS FAR...SO NOT ENTIRELY SURE HOW MUCH HAS FALLEN UNDER THAT HEAVIER BAND. FARTHER NORTH...WEBCAMS SHOW A SIMILAR STORY...WITH THE KRC CAM SHOWING LITTLE ADDITIONAL ACCUMULATION SINCE 1AM BUT CAMERAS IN HOUGHTON HAVE SHOWN HEAVY SNOW AT TIMES. WILL BE CURIOUS TO SEE SOME REPORTS IN THE MORNING...BUT WONDERING IF THE TRANSIENT NATURE OF THE LES WILL KEEP THE HEAVIER AMOUNTS ISOLATED. A POCKET OF DEEPER MOISTURE WITH THE SHORTWAVE MOVES THROUGH THIS MORNING AND ANOTHER AREA OF DEEP MOISTURE SLIDES THROUGH TONIGHT. THAT KEEPS INVERSION HEIGHTS UP AROUND 8-10KFT OVER THE WEST THIS MORNING...BUT SHOULD SLOWLY LOWER THIS AFTERNOON INTO TONIGHT AS THE AREA SEES INCREASING SUBSIDENCE FROM THE APPROACHING RIDGE OVER MINNESOTA. OVER THE EAST...THE INCREASED LAKE MODIFICATION AND LATER ARRIVAL OF THE APPROACHING RIDGE SHOULD KEEP INVERSION HEIGHTS IN THE 9-10KFT RANGE FOR MUCH OF THE NIGHT. WITH THE FAVORABLE LAKE EFFECT CONDITIONS...LOCATIONS AND AMOUNTS LARGELY DEPEND ON THE WINDS. TWO SURFACE TROUGHS WILL BE GRADUALLY SHIFTING WINDS THROUGH THE SHORT TERM PERIOD. THE FIRST WILL SLIDE THROUGH THIS MORNING AND SLOWLY SHIFT THE WINDS A LITTLE MORE WEST TO EVEN WEST-NORTHWEST OVER THE KEWEENAW PENINSULA. THAT SHOULD LEAD TO THE DOMINATE BAND (THAT HAS BEEN LOCATED FROM JUST NORTH OF THE APOSTLE ISLANDS AND THROUGH NORTHERN HOUGHTON COUNTY) TO SLOWLY SLIDE SOUTH WITH MORE WIDESPREAD WIND PARALLEL BANDS IMPACT THE REST OF THE KEWEENAW PENINSULA. WHILE THIS WIND SHIFT WILL PUSH THE LAKE EFFECT SNOW FARTHER SOUTH OVER EASTERN LAKE SUPERIOR...DON/T THINK THAT MUCH WILL BE IMPACTING THE EASTERN U.P. UNTIL THE SECONDARY TROUGH PUSHES THROUGH THIS EVENING AND SHIFTS THE WINDS TO THE NORTHWEST ACROSS LAKE SUPERIOR. THAT WILL FINALLY LEAD TO SOME LAKE EFFECT OVER THE EASTERN CWA...PRIMARILY EASTERN ALGER...NORTHERN SCHOOLCRAFT...AND LUCE COUNTIES. HIGH RESOLUTION MODELS ALL AGREE ON THAT IDEA...WITH A BURST OF MODERATE TO HEAVY SNOW TO OCCUR INITIALLY IN THE EVENING (LARGELY BETWEEN 00-03Z) NEAR THE LAKE SUPERIOR SHORELINE AS THE DOMINATE BAND SLIDES SOUTH BEFORE TRANSITIONING TO WIND PARALLEL BANDS FOR THE REST OF THE NIGHT AND INTO SATURDAY. WITH SOME INDICATIONS OF A LAND BREEZE OVER THE NORTH CENTRAL U.P. INCREASING CONVERGENCE...WOULD EXPECT THERE TO BE A STRONGER BAND SOMEWHERE BETWEEN MUNISING AND GRAND MARAIS AND LIKELY AFFECTING THE PICTURED ROCKS NATIONAL LAKE SHORE. WITH THAT EXPECTATION...BELIEVE SOME LOCATIONS SHOULD SEE THE 4IN/12HR CRITERIA FOR THE EASTERN AREAS AND WILL ISSUES A LAKE EFFECT SNOW ADVISORY FOR ALGER/LUCE AND NORTHERN SCHOOLCRAFT STARTING AT 00Z AND CONTINUING INTO SATURDAY. INTENSITY SHOULD REALLY DIMINISH LATE INTO THE NIGHT AND INTO SATURDAY AS INVERSION HEIGHTS ARE CUT IN HALF. AS FOR THE REST OF THE HEADLINES...HAVE LEFT THE EXISTING WARNING/ADVISORIES IN PLACE OVER THE WEST AND WHILE KEWEENAW COUNTY WILL LIKELY ONLY SEE ADVISORY SNOWFALL THE REST OF THE WAY...DON/T WANT TO ADJUST THE HEADLINE UNTIL WE START SEEING REPORTS. GOGEBIC IS THE MAIN QUESTION MARK...SINCE INVERSION HEIGHTS WILL BE FALLING AS THE WINDS FINALLY TURN MORE FAVORABLE TONIGHT. THOSE LOWERING INVERSION HEIGHTS WILL LIMIT THE INTENSITY BUT ALSO PUT THE ENTIRE CLOUD WITHIN THE DGZ AND LEAD TO FAIRLY FLUFFY SNOW. SINCE THE FORECAST ONLY HAS MARGINAL ADVISORY SNOW MAINLY NORTH OF THE POPULATION AREAS IN WESTERN GOGEBIC COUNTY...WILL NOT ISSUE AN ADVISORY FOR THEM AT THIS TIME. FINALLY...WILL BE A FAIRLY COLD DAY TODAY (AT LEAST WHEN COMPARED TO WHAT WE HAVE BEEN SEEING SO FAR THIS WINTER) WITH HIGHS IN THE UPPER TEENS OVER THE WEST AND THE LOW-MID 20S OVER THE EAST. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 336 AM EST FRI DEC 18 2015 NAM SHOWS A 500 MB TROUGH ON THE WEST COAST...A RIDGE OVER THE ROCKIES INTO THE PLAINS AND TROUGHING INTO THE ERN U.S. 12Z SAT. UPPER RIDGING THEN MOVES INTO THE UPPER GREAT LAKES ON SAT INTO SUN. ANOTHER SHORTWAVE MOVES INTO THE UPPER GREAT LAKES ON SUN NIGHT. LAKE EFFECT SNOW WINDS DOWN SAT MORNING AS INVERSION HEIGHTS FALL THROUGHOUT THE DAY AND STARTS SLOWLY WARMING ALOFT AND WINDS BACK TO THE WSW LATE. NEXT SYSTEM STARTS TO ARRIVE SUN AFTERNOON AND HAVE SLIGHT CHANCE POPS IN FOR THEN AND CHANCE POPS IN FOR SUN NIGHT WITH LIKELY POPS FOR THE EAST LATE SUN NIGHT. COULD BE SOME RAIN MIXED IN WITH THE SNOW FOR THE FAR SOUTH AND EAST FOR SUN NIGHT. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR TEMPERATURES. IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH ACROSS MOST OF THE U.S. WITH A SHORTWAVE IN THE UPPER GREAT LAKES 12Z MON. THERE IS ANOTHER SHORTWAVE OVER THE NORTHERN ROCKIES 12Z MON THAT MOVES INTO THE NORTHERN PLAINS 12Z TUE. MORE TROUGHING COMES INTO THE NORTHERN PLAINS 12Z WED AND THIS MOVES INTO THE UPPER GREAT LAKES WED NIGHT INTO THU. HAVE CHANCE POPS IN FOR MON AND THEN MOISTURE IS LIMITED UNTIL NEXT SYSTEM ARRIVES FOR TUE NIGHT AND WED WITH CHANCE POPS AGAIN. TEMPERATURES LOOK TO STAY ABOVE NORMAL FOR THIS FORECAST PERIOD AND PCPN WILL BE SNOW MIXED WITH RAIN. RAIN WILL BE CONFINED TO MAINLY ALONG LAKE MICHIGAN AND THE EAST HALF OF THE CWA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 648 AM EST FRI DEC 18 2015 EXPECT FAIRLY STEADY CONDITIONS AT KCMX/KSAW THROUGH THE TAF PERIOD...WEST TO EVENTUALLY NORTHWEST WIND LAKE EFFECT CONTINUES THROUGH TONIGHT. THAT LEAVES KCMX UNDER MVFR CEILINGS AND WITH THE LAKE EFFECT SNOW AND BLOWING SNOW (GUSTS IN THE 25-30KT RANGE)...VISIBILITIES WILL BE GENERALLY AROUND 2MI. THINK THE STRONGEST BAND WILL STAY SOUTH OF THE AREA THROUGH THE DAY AS WINDS SLOWLY TURN TO THE NORTHWEST...SO HAVE ONLY SHOWED VISIBILITIES BELOW A MILE FOR THIS MORNING. CAN/T COMPLETELY RULE OUT LOWER VISIBILITIES AFTER THAT...BUT FELT THAT THE LATEST TRENDS NEEDED TO BE FOLLOWED. AS FOR KIWD...THEY WILL SEE SOME LIGHT SNOW SHOWERS OR FLURRIES THIS MORNING...THEN AS BOUNDARY LAYER WINDS TURN MORE OUT OF THE WEST-NORTHWEST...SHOULD SEE LAKE EFFECT START TO IMPACT THE SITE...WITH IFR CEILINGS EXPECTED THROUGH THE NIGHT. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 404 AM EST FRI DEC 18 2015 A NEARLY STATIONARY LOW OVER FAR NORTHERN ONTARIO WILL CONTINUE TO PRODUCE WESTERLY GALES TODAY BEFORE A TROUGH SHIFTS WINDS TO THE NORTHWEST TONIGHT. THE CURRENT GALE WARNINGS LOOK TO BE IN GOOD SHAPE WITH THEM ENDING FROM WEST TO EAST LATE TONIGHT THROUGH SATURDAY AS A SURFACE RIDGE SLIDES THROUGH THE AREA. THAT SURFACE RIDGE WILL ONLY BRIEFLY DROP WINDS BELOW 20KTS...BEFORE SOUTHEASTERLY WINDS INCREASE ON SUNDAY AHEAD OF A LOW PRESSURE SYSTEM THAT WILL MOVE THROUGH THE UPPER GREAT LAKES REGION MONDAY MORNING. AS THAT LOW MOVES THROUGH...EXPECT WINDS TO BACK TO THE NORTH-NORTHWEST AND LEAD TO GUSTS TO 30KTS AT TIMES MONDAY AFTERNOON INTO MONDAY EVENING. FINALLY...WITH THE COLD AIR OVER THE WESTERN LAKE...DO HAVE SOME FREEZING SPRAY IN THE FORECAST FOR TODAY INTO SATURDAY MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW WARNING UNTIL 7 AM EST SATURDAY FOR MIZ001-003. LAKE EFFECT SNOW ADVISORY FROM 6 PM THIS EVENING TO 2 PM EST SATURDAY FOR MIZ006-007-085. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ002-004- 084. LAKE SUPERIOR... GALE WARNING UNTIL 1 PM EST SATURDAY FOR LSZ264>267. GALE WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY FOR LSZ162-263. GALE WARNING UNTIL 11 AM EST SATURDAY FOR LSZ244-245. GALE WARNING UNTIL 5 AM EST /4 AM CST/ SATURDAY FOR LSZ240>243. LAKE MICHIGAN... NONE. && $$ UPDATE...SRF SHORT TERM...SRF LONG TERM...07 AVIATION...SRF MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
648 AM EST FRI DEC 18 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 404 AM EST FRI DEC 18 2015 LAKE EFFECT SNOW IS THE PRIMARY FOCUS FOR THE SHORT TERM FORECAST...ALTHOUGH STUBBORN CLOUDS AND -SHSN OR FLURRIES CONTINUE TO AFFECT MUCH OF THE REST OF THE AREA. A 991MB SURFACE LOW REMAINS NEARLY STATIONARY OVER FAR NORTHERN ONTARIO THIS MORNING WHICH IS HELPING TO KEEP THE GENERALLY WESTERLY WINDS ACROSS LAKE SUPERIOR. THAT WESTERLY FLOW IS COMBINING WITH A SECONDARY UPPER TROUGH MOVING THROUGH WESTERN LAKE SUPERIOR AND THE ABUNDANT MOISTURE WITH IT...ALONG WITH RAP ANALYSIS 850MB TEMPS OF -12 TO -15C TO PRODUCE LAKE EFFECT SNOW IN THE WEST TO WEST- SOUTHWEST WINDS SNOW BELTS. BEFORE GETTING INTO THE LAKE EFFECT ASPECT...DID WANT TO MENTION THAT WILL SHOW LIGHT SNOW SHOWERS OVER THE INLAND AREAS THIS MORNING AND TAPERING OFF TO FLURRIES THROUGH THE REST OF THE DAY BASED OFF UPSTREAM OBS AND RADAR IN WISCONSIN AND MINNESOTA. BACK TO THE LAKE EFFECT...HAVE BEEN PICKING UP DECENT RETURNS OVER FAR NORTHERN ONTONAGON COUNTY AND PORTIONS OF NORTHERN HOUGHTON COUNTY THROUGH THE NIGHT (GENERALLY BETWEEN 6-8KFT) AND EXPECT THERE TO BE MODERATE TO HEAVY LES OCCURRING IN THOSE AREAS. LOOKING AT A WEBCAM IN ONTONAGON...ONLY LOOKS LIKE AN INCH OR SO HAS FALLEN THERE WITH THE HEAVIEST OCCURRING A FEW MILES FARTHER NORTH. WEBCAMS FARTHER INLAND AT TWIN LAKES ONLY SHOWS LIMITED ACCUMULATIONS THUS FAR...SO NOT ENTIRELY SURE HOW MUCH HAS FALLEN UNDER THAT HEAVIER BAND. FARTHER NORTH...WEBCAMS SHOW A SIMILAR STORY...WITH THE KRC CAM SHOWING LITTLE ADDITIONAL ACCUMULATION SINCE 1AM BUT CAMERAS IN HOUGHTON HAVE SHOWN HEAVY SNOW AT TIMES. WILL BE CURIOUS TO SEE SOME REPORTS IN THE MORNING...BUT WONDERING IF THE TRANSIENT NATURE OF THE LES WILL KEEP THE HEAVIER AMOUNTS ISOLATED. A POCKET OF DEEPER MOISTURE WITH THE SHORTWAVE MOVES THROUGH THIS MORNING AND ANOTHER AREA OF DEEP MOISTURE SLIDES THROUGH TONIGHT. THAT KEEPS INVERSION HEIGHTS UP AROUND 8-10KFT OVER THE WEST THIS MORNING...BUT SHOULD SLOWLY LOWER THIS AFTERNOON INTO TONIGHT AS THE AREA SEES INCREASING SUBSIDENCE FROM THE APPROACHING RIDGE OVER MINNESOTA. OVER THE EAST...THE INCREASED LAKE MODIFICATION AND LATER ARRIVAL OF THE APPROACHING RIDGE SHOULD KEEP INVERSION HEIGHTS IN THE 9-10KFT RANGE FOR MUCH OF THE NIGHT. WITH THE FAVORABLE LAKE EFFECT CONDITIONS...LOCATIONS AND AMOUNTS LARGELY DEPEND ON THE WINDS. TWO SURFACE TROUGHS WILL BE GRADUALLY SHIFTING WINDS THROUGH THE SHORT TERM PERIOD. THE FIRST WILL SLIDE THROUGH THIS MORNING AND SLOWLY SHIFT THE WINDS A LITTLE MORE WEST TO EVEN WEST-NORTHWEST OVER THE KEWEENAW PENINSULA. THAT SHOULD LEAD TO THE DOMINATE BAND (THAT HAS BEEN LOCATED FROM JUST NORTH OF THE APOSTLE ISLANDS AND THROUGH NORTHERN HOUGHTON COUNTY) TO SLOWLY SLIDE SOUTH WITH MORE WIDESPREAD WIND PARALLEL BANDS IMPACT THE REST OF THE KEWEENAW PENINSULA. WHILE THIS WIND SHIFT WILL PUSH THE LAKE EFFECT SNOW FARTHER SOUTH OVER EASTERN LAKE SUPERIOR...DON/T THINK THAT MUCH WILL BE IMPACTING THE EASTERN U.P. UNTIL THE SECONDARY TROUGH PUSHES THROUGH THIS EVENING AND SHIFTS THE WINDS TO THE NORTHWEST ACROSS LAKE SUPERIOR. THAT WILL FINALLY LEAD TO SOME LAKE EFFECT OVER THE EASTERN CWA...PRIMARILY EASTERN ALGER...NORTHERN SCHOOLCRAFT...AND LUCE COUNTIES. HIGH RESOLUTION MODELS ALL AGREE ON THAT IDEA...WITH A BURST OF MODERATE TO HEAVY SNOW TO OCCUR INITIALLY IN THE EVENING (LARGELY BETWEEN 00-03Z) NEAR THE LAKE SUPERIOR SHORELINE AS THE DOMINATE BAND SLIDES SOUTH BEFORE TRANSITIONING TO WIND PARALLEL BANDS FOR THE REST OF THE NIGHT AND INTO SATURDAY. WITH SOME INDICATIONS OF A LAND BREEZE OVER THE NORTH CENTRAL U.P. INCREASING CONVERGENCE...WOULD EXPECT THERE TO BE A STRONGER BAND SOMEWHERE BETWEEN MUNISING AND GRAND MARAIS AND LIKELY AFFECTING THE PICTURED ROCKS NATIONAL LAKE SHORE. WITH THAT EXPECTATION...BELIEVE SOME LOCATIONS SHOULD SEE THE 4IN/12HR CRITERIA FOR THE EASTERN AREAS AND WILL ISSUES A LAKE EFFECT SNOW ADVISORY FOR ALGER/LUCE AND NORTHERN SCHOOLCRAFT STARTING AT 00Z AND CONTINUING INTO SATURDAY. INTENSITY SHOULD REALLY DIMINISH LATE INTO THE NIGHT AND INTO SATURDAY AS INVERSION HEIGHTS ARE CUT IN HALF. AS FOR THE REST OF THE HEADLINES...HAVE LEFT THE EXISTING WARNING/ADVISORIES IN PLACE OVER THE WEST AND WHILE KEWEENAW COUNTY WILL LIKELY ONLY SEE ADVISORY SNOWFALL THE REST OF THE WAY...DON/T WANT TO ADJUST THE HEADLINE UNTIL WE START SEEING REPORTS. GOGEBIC IS THE MAIN QUESTION MARK...SINCE INVERSION HEIGHTS WILL BE FALLING AS THE WINDS FINALLY TURN MORE FAVORABLE TONIGHT. THOSE LOWERING INVERSION HEIGHTS WILL LIMIT THE INTENSITY BUT ALSO PUT THE ENTIRE CLOUD WITHIN THE DGZ AND LEAD TO FAIRLY FLUFFY SNOW. SINCE THE FORECAST ONLY HAS MARGINAL ADVISORY SNOW MAINLY NORTH OF THE POPULATION AREAS IN WESTERN GOGEBIC COUNTY...WILL NOT ISSUE AN ADVISORY FOR THEM AT THIS TIME. FINALLY...WILL BE A FAIRLY COLD DAY TODAY (AT LEAST WHEN COMPARED TO WHAT WE HAVE BEEN SEEING SO FAR THIS WINTER) WITH HIGHS IN THE UPPER TEENS OVER THE WEST AND THE LOW-MID 20S OVER THE EAST. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 336 AM EST FRI DEC 18 2015 NAM SHOWS A 500 MB TROUGH ON THE WEST COAST...A RIDGE OVER THE ROCKIES INTO THE PLAINS AND TROUGHING INTO THE ERN U.S. 12Z SAT. UPPER RIDGING THEN MOVES INTO THE UPPER GREAT LAKES ON SAT INTO SUN. ANOTHER SHORTWAVE MOVES INTO THE UPPER GREAT LAKES ON SUN NIGHT. LAKE EFFECT SNOW WINDS DOWN SAT MORNING AS INVERSION HEIGHTS FALL THROUGHOUT THE DAY AND STARTS SLOWLY WARMING ALOFT AND WINDS BACK TO THE WSW LATE. NEXT SYSTEM STARTS TO ARRIVE SUN AFTERNOON AND HAVE SLIGHT CHANCE POPS IN FOR THEN AND CHANCE POPS IN FOR SUN NIGHT WITH LIKELY POPS FOR THE EAST LATE SUN NIGHT. COULD BE SOME RAIN MIXED IN WITH THE SNOW FOR THE FAR SOUTH AND EAST FOR SUN NIGHT. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR TEMPERATURES. IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH ACROSS MOST OF THE U.S. WITH A SHORTWAVE IN THE UPPER GREAT LAKES 12Z MON. THERE IS ANOTHER SHORTWAVE OVER THE NORTHERN ROCKIES 12Z MON THAT MOVES INTO THE NORTHERN PLAINS 12Z TUE. MORE TROUGHING COMES INTO THE NORTHERN PLAINS 12Z WED AND THIS MOVES INTO THE UPPER GREAT LAKES WED NIGHT INTO THU. HAVE CHANCE POPS IN FOR MON AND THEN MOISTURE IS LIMITED UNTIL NEXT SYSTEM ARRIVES FOR TUE NIGHT AND WED WITH CHANCE POPS AGAIN. TEMPERATURES LOOK TO STAY ABOVE NORMAL FOR THIS FORECAST PERIOD AND PCPN WILL BE SNOW MIXED WITH RAIN. RAIN WILL BE CONFINED TO MAINLY ALONG LAKE MICHIGAN AND THE EAST HALF OF THE CWA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 648 AM EST FRI DEC 18 2015 EXPECT FAIRLY STEADY CONDITIONS AT KCMX/KSAW THROUGH THE TAF PERIOD...WEST TO EVENTUALLY NORTHWEST WIND LAKE EFFECT CONTINUES THROUGH TONIGHT. THAT LEAVES KCMX UNDER MVFR CEILINGS AND WITH THE LAKE EFFECT SNOW AND BLOWING SNOW (GUSTS IN THE 25-30KT RANGE)...VISIBILITIES WILL BE GENERALLY AROUND 2MI. THINK THE STRONGEST BAND WILL STAY SOUTH OF THE AREA THROUGH THE DAY AS WINDS SLOWLY TURN TO THE NORTHWEST...SO HAVE ONLY SHOWED VISIBILITIES BELOW A MILE FOR THIS MORNING. CAN/T COMPLETELY RULE OUT LOWER VISIBILITIES AFTER THAT...BUT FELT THAT THE LATEST TRENDS NEEDED TO BE FOLLOWED. AS FOR KIWD...THEY WILL SEE SOME LIGHT SNOW SHOWERS OR FLURRIES THIS MORNING...THEN AS BOUNDARY LAYER WINDS TURN MORE OUT OF THE WEST-NORTHWEST...SHOULD SEE LAKE EFFECT START TO IMPACT THE SITE...WITH IFR CEILINGS EXPECTED THROUGH THE NIGHT. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 404 AM EST FRI DEC 18 2015 A NEARLY STATIONARY LOW OVER FAR NORTHERN ONTARIO WILL CONTINUE TO PRODUCE WESTERLY GALES TODAY BEFORE A TROUGH SHIFTS WINDS TO THE NORTHWEST TONIGHT. THE CURRENT GALE WARNINGS LOOK TO BE IN GOOD SHAPE WITH THEM ENDING FROM WEST TO EAST LATE TONIGHT THROUGH SATURDAY AS A SURFACE RIDGE SLIDES THROUGH THE AREA. THAT SURFACE RIDGE WILL ONLY BRIEFLY DROP WINDS BELOW 20KTS...BEFORE SOUTHEASTERLY WINDS INCREASE ON SUNDAY AHEAD OF A LOW PRESSURE SYSTEM THAT WILL MOVE THROUGH THE UPPER GREAT LAKES REGION MONDAY MORNING. AS THAT LOW MOVES THROUGH...EXPECT WINDS TO BACK TO THE NORTH-NORTHWEST AND LEAD TO GUSTS TO 30KTS AT TIMES MONDAY AFTERNOON INTO MONDAY EVENING. FINALLY...WITH THE COLD AIR OVER THE WESTERN LAKE...DO HAVE SOME FREEZING SPRAY IN THE FORECAST FOR TODAY INTO SATURDAY MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW WARNING UNTIL 7 AM EST SATURDAY FOR MIZ001-003. LAKE EFFECT SNOW ADVISORY FROM 6 PM THIS EVENING TO 2 PM EST SATURDAY FOR MIZ006-007-085. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ002. LAKE SUPERIOR... GALE WARNING UNTIL 1 PM EST SATURDAY FOR LSZ264>267. GALE WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY FOR LSZ162-263. GALE WARNING UNTIL 11 AM EST SATURDAY FOR LSZ244-245. GALE WARNING UNTIL 5 AM EST /4 AM CST/ SATURDAY FOR LSZ240>243. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...07 AVIATION...SRF MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
405 AM EST FRI DEC 18 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 404 AM EST FRI DEC 18 2015 LAKE EFFECT SNOW IS THE PRIMARY FOCUS FOR THE SHORT TERM FORECAST...ALTHOUGH STUBBORN CLOUDS AND -SHSN OR FLURRIES CONTINUE TO AFFECT MUCH OF THE REST OF THE AREA. A 991MB SURFACE LOW REMAINS NEARLY STATIONARY OVER FAR NORTHERN ONTARIO THIS MORNING WHICH IS HELPING TO KEEP THE GENERALLY WESTERLY WINDS ACROSS LAKE SUPERIOR. THAT WESTERLY FLOW IS COMBINING WITH A SECONDARY UPPER TROUGH MOVING THROUGH WESTERN LAKE SUPERIOR AND THE ABUNDANT MOISTURE WITH IT...ALONG WITH RAP ANALYSIS 850MB TEMPS OF -12 TO -15C TO PRODUCE LAKE EFFECT SNOW IN THE WEST TO WEST- SOUTHWEST WINDS SNOW BELTS. BEFORE GETTING INTO THE LAKE EFFECT ASPECT...DID WANT TO MENTION THAT WILL SHOW LIGHT SNOW SHOWERS OVER THE INLAND AREAS THIS MORNING AND TAPERING OFF TO FLURRIES THROUGH THE REST OF THE DAY BASED OFF UPSTREAM OBS AND RADAR IN WISCONSIN AND MINNESOTA. BACK TO THE LAKE EFFECT...HAVE BEEN PICKING UP DECENT RETURNS OVER FAR NORTHERN ONTONAGON COUNTY AND PORTIONS OF NORTHERN HOUGHTON COUNTY THROUGH THE NIGHT (GENERALLY BETWEEN 6-8KFT) AND EXPECT THERE TO BE MODERATE TO HEAVY LES OCCURRING IN THOSE AREAS. LOOKING AT A WEBCAM IN ONTONAGON...ONLY LOOKS LIKE AN INCH OR SO HAS FALLEN THERE WITH THE HEAVIEST OCCURRING A FEW MILES FARTHER NORTH. WEBCAMS FARTHER INLAND AT TWIN LAKES ONLY SHOWS LIMITED ACCUMULATIONS THUS FAR...SO NOT ENTIRELY SURE HOW MUCH HAS FALLEN UNDER THAT HEAVIER BAND. FARTHER NORTH...WEBCAMS SHOW A SIMILAR STORY...WITH THE KRC CAM SHOWING LITTLE ADDITIONAL ACCUMULATION SINCE 1AM BUT CAMERAS IN HOUGHTON HAVE SHOWN HEAVY SNOW AT TIMES. WILL BE CURIOUS TO SEE SOME REPORTS IN THE MORNING...BUT WONDERING IF THE TRANSIENT NATURE OF THE LES WILL KEEP THE HEAVIER AMOUNTS ISOLATED. A POCKET OF DEEPER MOISTURE WITH THE SHORTWAVE MOVES THROUGH THIS MORNING AND ANOTHER AREA OF DEEP MOISTURE SLIDES THROUGH TONIGHT. THAT KEEPS INVERSION HEIGHTS UP AROUND 8-10KFT OVER THE WEST THIS MORNING...BUT SHOULD SLOWLY LOWER THIS AFTERNOON INTO TONIGHT AS THE AREA SEES INCREASING SUBSIDENCE FROM THE APPROACHING RIDGE OVER MINNESOTA. OVER THE EAST...THE INCREASED LAKE MODIFICATION AND LATER ARRIVAL OF THE APPROACHING RIDGE SHOULD KEEP INVERSION HEIGHTS IN THE 9-10KFT RANGE FOR MUCH OF THE NIGHT. WITH THE FAVORABLE LAKE EFFECT CONDITIONS...LOCATIONS AND AMOUNTS LARGELY DEPEND ON THE WINDS. TWO SURFACE TROUGHS WILL BE GRADUALLY SHIFTING WINDS THROUGH THE SHORT TERM PERIOD. THE FIRST WILL SLIDE THROUGH THIS MORNING AND SLOWLY SHIFT THE WINDS A LITTLE MORE WEST TO EVEN WEST-NORTHWEST OVER THE KEWEENAW PENINSULA. THAT SHOULD LEAD TO THE DOMINATE BAND (THAT HAS BEEN LOCATED FROM JUST NORTH OF THE APOSTLE ISLANDS AND THROUGH NORTHERN HOUGHTON COUNTY) TO SLOWLY SLIDE SOUTH WITH MORE WIDESPREAD WIND PARALLEL BANDS IMPACT THE REST OF THE KEWEENAW PENINSULA. WHILE THIS WIND SHIFT WILL PUSH THE LAKE EFFECT SNOW FARTHER SOUTH OVER EASTERN LAKE SUPERIOR...DON/T THINK THAT MUCH WILL BE IMPACTING THE EASTERN U.P. UNTIL THE SECONDARY TROUGH PUSHES THROUGH THIS EVENING AND SHIFTS THE WINDS TO THE NORTHWEST ACROSS LAKE SUPERIOR. THAT WILL FINALLY LEAD TO SOME LAKE EFFECT OVER THE EASTERN CWA...PRIMARILY EASTERN ALGER...NORTHERN SCHOOLCRAFT...AND LUCE COUNTIES. HIGH RESOLUTION MODELS ALL AGREE ON THAT IDEA...WITH A BURST OF MODERATE TO HEAVY SNOW TO OCCUR INITIALLY IN THE EVENING (LARGELY BETWEEN 00-03Z) NEAR THE LAKE SUPERIOR SHORELINE AS THE DOMINATE BAND SLIDES SOUTH BEFORE TRANSITIONING TO WIND PARALLEL BANDS FOR THE REST OF THE NIGHT AND INTO SATURDAY. WITH SOME INDICATIONS OF A LAND BREEZE OVER THE NORTH CENTRAL U.P. INCREASING CONVERGENCE...WOULD EXPECT THERE TO BE A STRONGER BAND SOMEWHERE BETWEEN MUNISING AND GRAND MARAIS AND LIKELY AFFECTING THE PICTURED ROCKS NATIONAL LAKE SHORE. WITH THAT EXPECTATION...BELIEVE SOME LOCATIONS SHOULD SEE THE 4IN/12HR CRITERIA FOR THE EASTERN AREAS AND WILL ISSUES A LAKE EFFECT SNOW ADVISORY FOR ALGER/LUCE AND NORTHERN SCHOOLCRAFT STARTING AT 00Z AND CONTINUING INTO SATURDAY. INTENSITY SHOULD REALLY DIMINISH LATE INTO THE NIGHT AND INTO SATURDAY AS INVERSION HEIGHTS ARE CUT IN HALF. AS FOR THE REST OF THE HEADLINES...HAVE LEFT THE EXISTING WARNING/ADVISORIES IN PLACE OVER THE WEST AND WHILE KEWEENAW COUNTY WILL LIKELY ONLY SEE ADVISORY SNOWFALL THE REST OF THE WAY...DON/T WANT TO ADJUST THE HEADLINE UNTIL WE START SEEING REPORTS. GOGEBIC IS THE MAIN QUESTION MARK...SINCE INVERSION HEIGHTS WILL BE FALLING AS THE WINDS FINALLY TURN MORE FAVORABLE TONIGHT. THOSE LOWERING INVERSION HEIGHTS WILL LIMIT THE INTENSITY BUT ALSO PUT THE ENTIRE CLOUD WITHIN THE DGZ AND LEAD TO FAIRLY FLUFFY SNOW. SINCE THE FORECAST ONLY HAS MARGINAL ADVISORY SNOW MAINLY NORTH OF THE POPULATION AREAS IN WESTERN GOGEBIC COUNTY...WILL NOT ISSUE AN ADVISORY FOR THEM AT THIS TIME. FINALLY...WILL BE A FAIRLY COLD DAY TODAY (AT LEAST WHEN COMPARED TO WHAT WE HAVE BEEN SEEING SO FAR THIS WINTER) WITH HIGHS IN THE UPPER TEENS OVER THE WEST AND THE LOW-MID 20S OVER THE EAST. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 336 AM EST FRI DEC 18 2015 NAM SHOWS A 500 MB TROUGH ON THE WEST COAST...A RIDGE OVER THE ROCKIES INTO THE PLAINS AND TROUGHING INTO THE ERN U.S. 12Z SAT. UPPER RIDGING THEN MOVES INTO THE UPPER GREAT LAKES ON SAT INTO SUN. ANOTHER SHORTWAVE MOVES INTO THE UPPER GREAT LAKES ON SUN NIGHT. LAKE EFFECT SNOW WINDS DOWN SAT MORNING AS INVERSION HEIGHTS FALL THROUGHOUT THE DAY AND STARTS SLOWLY WARMING ALOFT AND WINDS BACK TO THE WSW LATE. NEXT SYSTEM STARTS TO ARRIVE SUN AFTERNOON AND HAVE SLIGHT CHANCE POPS IN FOR THEN AND CHANCE POPS IN FOR SUN NIGHT WITH LIKELY POPS FOR THE EAST LATE SUN NIGHT. COULD BE SOME RAIN MIXED IN WITH THE SNOW FOR THE FAR SOUTH AND EAST FOR SUN NIGHT. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR TEMPERATURES. IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH ACROSS MOST OF THE U.S. WITH A SHORTWAVE IN THE UPPER GREAT LAKES 12Z MON. THERE IS ANOTHER SHORTWAVE OVER THE NORTHERN ROCKIES 12Z MON THAT MOVES INTO THE NORTHERN PLAINS 12Z TUE. MORE TROUGHING COMES INTO THE NORTHERN PLAINS 12Z WED AND THIS MOVES INTO THE UPPER GREAT LAKES WED NIGHT INTO THU. HAVE CHANCE POPS IN FOR MON AND THEN MOISTURE IS LIMITED UNTIL NEXT SYSTEM ARRIVES FOR TUE NIGHT AND WED WITH CHANCE POPS AGAIN. TEMPERATURES LOOK TO STAY ABOVE NORMAL FOR THIS FORECAST PERIOD AND PCPN WILL BE SNOW MIXED WITH RAIN. RAIN WILL BE CONFINED TO MAINLY ALONG LAKE MICHIGAN AND THE EAST HALF OF THE CWA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1154 PM EST THU DEC 17 2015 UNDER A WESTERLY WIND...LAKE EFFECT SNOW SHOWERS AND BLSN WILL IMPACT KCMX THRU THIS FCST PERIOD. IN GENERAL...EXPECT LIFR CONDITIONS TO PREVAIL WITH PERIODS OF IFR. HOWEVER...AS IS TYPICAL FOR LAKE EFFECT...CONDITIONS WILL BE HIGHLY VARIABLE WITH SOME MVFR AND PERHAPS BRIEF VFR AT TIMES. THERE MAY BE AN OVERALL IMPROVING TREND TO PREVAILING IFR BEGINNING LATE THIS AFTN/EVENING. AT KIWD... WIND DIRECTION WILL KEEP LAKE EFFECT SNOW SHOWERS N OF THE TERMINAL THRU AT LEAST THE MORNING...THOUGH MVFR CIGS SHOULD GENERALLY BE THE RULE. SLIGHT VEERING OF WIND THIS AFTN/EVENING MAY BRING MORE PERSISTENT SNOW SHOWERS TO KIWD IN THE AFTN. CONDITIONS MAY FALL TO IFR THIS EVENING. AT KSAW...DOWNSLOPING WESTERLY WIND SHOULD ALLOW FOR VFR CONDITIONS TO PREVAIL THRU THE FCST PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 404 AM EST FRI DEC 18 2015 A NEARLY STATIONARY LOW OVER FAR NORTHERN ONTARIO WILL CONTINUE TO PRODUCE WESTERLY GALES TODAY BEFORE A TROUGH SHIFTS WINDS TO THE NORTHWEST TONIGHT. THE CURRENT GALE WARNINGS LOOK TO BE IN GOOD SHAPE WITH THEM ENDING FROM WEST TO EAST LATE TONIGHT THROUGH SATURDAY AS A SURFACE RIDGE SLIDES THROUGH THE AREA. THAT SURFACE RIDGE WILL ONLY BRIEFLY DROP WINDS BELOW 20KTS...BEFORE SOUTHEASTERLY WINDS INCREASE ON SUNDAY AHEAD OF A LOW PRESSURE SYSTEM THAT WILL MOVE THROUGH THE UPPER GREAT LAKES REGION MONDAY MORNING. AS THAT LOW MOVES THROUGH...EXPECT WINDS TO BACK TO THE NORTH-NORTHWEST AND LEAD TO GUSTS TO 30KTS AT TIMES MONDAY AFTERNOON INTO MONDAY EVENING. FINALLY...WITH THE COLD AIR OVER THE WESTERN LAKE...DO HAVE SOME FREEZING SPRAY IN THE FORECAST FOR TODAY INTO SATURDAY MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW WARNING UNTIL 7 AM EST SATURDAY FOR MIZ001-003. LAKE EFFECT SNOW ADVISORY FROM 6 PM THIS EVENING TO 2 PM EST SATURDAY FOR MIZ006-007-085. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ002. LAKE SUPERIOR... GALE WARNING UNTIL 1 PM EST SATURDAY FOR LSZ264>267. GALE WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY FOR LSZ162-263. GALE WARNING UNTIL 11 AM EST SATURDAY FOR LSZ244-245. GALE WARNING UNTIL 5 AM EST /4 AM CST/ SATURDAY FOR LSZ240>243. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...07 AVIATION...ROLFSON MARINE...SRF
AREA FORECAST DISCUSSION
NWS DULUTH MN
331 PM CST FRI DEC 18 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 330 PM CST FRI DEC 18 2015 A VERTICALLY STACKED SYSTEM WAS MEANDERING AROUND NEAR HUDSON BAY AT 20Z. THIS LEFT THE FORECAST AREA UNDER A NW FLOW ALOFT. COLD AIR WAS PUSHING ACROSS THE REGION FROM THIS SYSTEM ALONG WITH THE LAST SHORT WAVE TROF ASSOCIATED WITH THIS SYSTEM. AS SUCH...CLOUDS CONTINUED TO DEVELOP/ROTATE ACROSS THE FORECAST AREA THIS AFTERNOON. A FEW STREAKS OF SNOW SHOWERS WERE ALSO CROSSING THROUGH THANKS TO SOME POSITIVE VORTICITY ADVECTION. SOME CLEARING WAS NOTED OVER THE WESTERN EDGE OF THE AREA AS DRY AIR FROM HIGH PRESSURE WAS BEGINNING TO ERODE CLOUD COVER. THERE WAS STILL A BIT OF CLOUD COVER UPSTREAM IN MANITOBA THAT APPEARS TO BE HEADED FOR THE NORTHERN PORTION OF THE REGION. WILL KEEP A BIT OF CLOUD COVER AROUND TONIGHT WHICH WILL KEEP THE TEMPS FROM FALLING TOO FAR. HOWEVER...SINGLE DIGITS FOR MINIMUM TEMPERATURES TONIGHT ARE REASONABLE. LAKE EFFECT SNOW SHOWERS HAVE BEEN OCCURRING ALONG THE BAYFIELD PENINSULA WITH A WESTERLY FLOW OFF OF LAKE SUPERIOR. CHECKED WITH A SNOW SPOTTER BETWEEN CORNUCOPIA AND BAYFIELD AND THEY REPORTED ABOUT ONE THIRD OF AN INCH TODAY. WITH DRIER AIR WORKING ITS WAY ACROSS THIS AREA...DEW POINTS HAVE DROPPED TWO DEGREES FAHRENHEIT IN THE LAST HOUR...SNOW AMOUNTS WILL BE DIMINISHING. COLDEST AIR ACCORDING TO THE NAM12 MOVES SOUTH OF THIS AREA BY 03Z SATURDAY. BASED ON THESE FACTORS...HAVE GONE WITH A GRADUAL LOWERING OF POPS THROUGH 03Z THIS EVENING ALONG THE BAYFIELD PENINSULA. WITH A WESTERLY COMPONENT TO THE WIND OVER THE TYPICAL LAKE EFFECT SNOW SPOTS...NOT A GOOD INDICATOR FOR ACCUMULATIONS. DO HAVE SOME LOW POPS OVER EASTERN IRON COUNTY FOR ANY SNOW SHOWERS THAT MAY DEVELOP. UPPER LEVEL/SFC RIDGING COVER THE REGION ON SATURDAY. THIS WILL ALLOW FOR THE MOST SUNSHINE TO AFFECT THE AREA IN SEVERAL DAYS. HOWEVER...CLOUDS WILL BE ON THE INCREASE THROUGH THE DAY AS MID AND HIGH CLOUDS ARRIVE DUE TO THE WARM AIR ADVECTION AHEAD OF A MID LEVEL TROF AND DEVELOPING SFC LOW OVER THE DAKOTAS LATE SATURDAY AFTERNOON. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 330 PM CST FRI DEC 18 2015 A BROAD UPPER RIDGE WILL WILL EXIST AT THE START OF THE EXTENDED PERIOD FROM NORTHWEST ONTARIO/SOUTHERN MANITOBA SOUTH THROUGH THE CENTRAL CONUS. SEVERAL SHORTWAVES WILL MOVE THROUGH THE REGION WITH A MORE SIGNIFICANT SYSTEM IMPACTING THE NORTHLAND AROUND MID WEEK. A WEAK AREA OF LOW PRESSURE WILL MOVE THROUGH THE AREA LATE SATURDAY NIGHT INTO SUNDAY NIGHT. WAA AHEAD OF THIS LOW MAY CAUSE SOME LIGHT SNOW TO OCCUR OVER FAR NORTHERN MINNESOTA AND POSSIBLY SOME LIGHT FREEZING DRIZZLE. SOUTHERLY WINDS MAY ALSO CAUSE SOME LAKE ENHANCED SNOW TO OCCUR ALONG A PORTION OF THE NORTH SHORE...MAINLY NORTH AND EAST OF SILVER BAY SATURDAY NIGHT. WE INCREASED POPS UP THERE...ESPECIALLY DURING THE EVENING BEFORE 850/925MB TEMPS START TO RISE. SOUNDINGS SUGGEST THERE MAY BE A LACK OF ICE CRYSTALS IN THE MOIST PORTION OF THE SOUNDINGS LEADING TO FREEZING DRIZZLE SUNDAY INTO SUNDAY NIGHT. AT THIS TIME...ANY SNOW OR ICE ACCUMULATION SHOULD BE LIGHT. WEAK HIGH PRESSURE WILL KEEP MOST AREAS DRY ON MONDAY. THE GFS/ECMWF START TO DIVERGE ON THEIR SOLUTIONS FOR MONDAY NIGHT INTO THE REST OF THE PERIOD. THE GFS IS FASTER AND STRONGER WITH A SHORTWAVE FOR MONDAY NIGHT INTO TUESDAY. A STRONGER SHORTWAVE IS THEN EXPECTED TO IMPACT THE REGION MID WEEK. THERE REMAINS TIMING AND TRACK DIFFERENCES BETWEEN THE GFS/ECMWF WITH THAT LOW PRESSURE SYSTEM FOR MID WEEK. THE ECMWF DRAWS WARMER AIR FURTHER INTO THE NORTHLAND THAN THE GFS. AT THIS TIME...WE HAVE A CHANCE FOR PRECIP TUESDAY THROUGH WEDNESDAY NIGHT...THEN DIMINISH POPS AFTER THAT. PRECIP TYPE COULD BE A WINTRY MIX...BUT WE LIMITED THE PRECIP TYPES TO RAIN/SNOW AT THIS TIME. HIGH TEMPERATURES WILL RANGE FROM THE MID TWENTIES TO LOWER THIRTIES SUNDAY...DROP TO 20 TO 30 ON MONDAY BEFORE RISING AGAIN TUESDAY DUE TO WAA AHEAD OF THE APPROACHING LOW. TUESDAY AND WEDNESDAY WILL BE IN THE UPPER TWENTIES TO UPPER THIRTIES...THEN TEMPERATURES WILL DROP SEVERAL DEGREES BEHIND THE LOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1129 AM CST FRI DEC 18 2015 COLD AIR ALOFT AND LOW LEVEL MOISTURE WILL CONTINUE TO PRODUCE MVFR CEILINGS AND SNOW SHOWERS THIS AFTERNOON INTO THE EVENING. AN AREA OF HIGH PRESSURE WILL THEN BUILD INTO THE NORTHLAND LATER TONIGHT INTO SATURDAY. THE SNOW SHOWERS WILL OCCASIONALLY DROP VSBYS TO IFR. WE DO EXPECT THE MVFR CEILINGS TO GRADUALLY LIFT FROM SOUTHWEST TO NORTHEAST TONIGHT INTO SATURDAY. THERE ARE SOME BREAKS IN THE CLOUDS THAT HAVE DEVELOPED ALREADY THIS AFTERNOON BUT THE RAP SUGGESTS THEY WILL AT LEAST PARTIALLY FILL BACK IN THROUGH THE AFTERNOON BEFORE DISSIPATING AGAIN TONIGHT. GUSTY WEST/NORTHWEST WINDS WILL CONTINUE...THEN DIMINISH TONIGHT. && .PRELIMINARY POINT TEMPS/POPS... DLH 6 19 17 30 / 0 0 10 30 INL 3 16 13 25 / 10 0 20 20 BRD 4 21 17 30 / 0 0 10 20 HYR 7 21 17 34 / 0 0 10 20 ASX 10 22 18 34 / 10 0 10 20 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...SMALL CRAFT ADVISORY UNTIL 10 AM CST SATURDAY FOR LSZ121-146>148. SMALL CRAFT ADVISORY UNTIL 4 AM CST SATURDAY FOR LSZ140>145. && $$ SHORT TERM...GSF LONG TERM...MELDE AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1129 AM CST FRI DEC 18 2015 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 313 AM CST FRI DEC 18 2015 SHORT TERM FOCUS ON BAND OF LAKE EFFECT SNOW CURRENTLY IMPACTING THE NORTHERN PORTION OF THE BAYFIELD PENINSULA...INCLUDING THE CORRIDOR ALONG HIGHWAY 13 FROM PORT WING TO CORNUCOPIA AND RED CLIFF. THE DLHWRF HAS HAD A VERY GOOD HANDLE ON THE PLACEMENT AND TIMING OF THIS LES BAND...AND SUGGESTS CONDITIONS REMAIN FAVORABLE WITH WESTERLY TRAJECTORIES AND STEEP LAPSE RATES THROUGH THE AFTERNOON...THEN GRADUALLY DISSIPATING DURING THE EVENING AS PROFILES BEGIN TO DRY AND INVERSION HEIGHTS LOWER. SNOWFALL AMOUNTS ARE EXTREMELY DIFFICULT TO PIN DOWN DUE TO THE MICROSCALE DYNAMICS OF THE LES BAND AND LACK OF REPORTS. BASED ON THE DLHWRF...HAVE INCLUDED SNOWFALL TOTALS OF AROUND 4 INCHES ASSOCIATED WITH THE LES. HOWEVER...BASED ON CURRENT RADAR REFLECTIVITY SHOWING RETURNS NEAR 30 DBZ AT TIMES...THERE MAY BE LOCALLY HIGHER AMOUNTS. ELSEWHERE...THE CYCLONIC FLOW AND 850HPA TEMPS IN THE NEGATIVE 20S WILL CONTINUE TO PRODUCE INSTABILITY SNOW SHOWERS OR FLURRIES THROUGH THE DAY. THE SNOW SHOWERS WILL FINALLY END FORM WEST TO EAST OVERNIGHT WITH APPROACHING SFC RIDGE. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 313 AM CST FRI DEC 18 2015 AN INVERTED SURFACE TROUGH AND ASSOCIATED UPPER WAVE WILL MOVE ACROSS THE CENTRAL CONUS INTO THE WESTERN GREAT LAKES SUNDAY MORNING INTO MONDAY MORNING. A BROAD AREA OF WEAK WAA AND MOISTURE ADVECTION FROM THE SOUTH WILL INDUCE ENOUGH LAYER LIFTING AHEAD OF THIS SYSTEM TO PRODUCE WIDESPREAD SNOW ACROSS THE NORTHLAND. WILL ALSO SEE THE POTENTIAL FOR A WINTRY MIX FROM AROUND BRAINERD MN TO SPOONER WI LATE SUNDAY MORNING INTO THE AFTERNOON AS A LAYER OF WARMER AIR ALOFT ROTATES EWD THROUGH SRN MN. THE MAXIMUM TEMPERATURE IN THE LAYER ALOFT DOES NOT APPEAR TO BE WARM ENOUGH FOR COMPLETE MELTING OF THE SNOW/ICE CRYSTALS...SO THE P-TYPES WILL LIKELY BE A MIX OF SNOW AND SLEET ALONG THIS CORRIDOR. AREAS FURTHER TO THE NORTH WILL SEE ALL SNOW. SNOWFALL AMOUNTS WILL RANGE FROM 1 TO 3 INCHES WITH THE HIGHEST AMTS ALONG AND WEST OF THE IRON RANGE. AS THIS SYSTEM SLIDES TO THE EAST ON MONDAY A RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST AND ALLOW FOR QUIET WEATHER CONDITIONS AND MILD TEMPERATURES THROUGH MONDAY NIGHT. A WEAK UPPER WAVE WILL MOVE IN QUICKLY FROM THE WEST EARLY TUESDAY MORNING AND PRODUCE A BRIEF PERIOD OF LIGHT SNOW ACROSS THE NORTHLAND. A SLIGHT REPRIEVE WILL BE SEEN LATER ON TUESDAY BEFORE THE NEXT SYSTEM PUSHES IN FROM THE WEST TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THERE ARE SOME DIFFERENCES AMONG MODELS WITH THE TRACK AND INTENSITY OF THIS SYSTEM. WITH THE GFS AND GEM STRENGTHENING THE SFC LOW OVER WISCONSIN AND ENOUGH COLD AIR ON THE BACK SIDE OF THE SYSTEM...THERE IS THE POTENTIAL FOR ANOTHER ROUND OF SIGNIFICANT SNOWFALL OVER THE NORTHLAND. SO WILL NEED TO KEEP A CLOSE EYE ON THE TRENDS OF THE MODELS OVER THE NEXT SEVERAL DAYS. WILL LIKELY SEE ANOTHER PERIOD OF LIGHT SNOW/FLURRIES AMIDST A TRAILING COLD CANADIAN AIR MASS LATER IN THE WEEK. HIGHS ACROSS THE REGION WILL REMAIN STEADY EARLY IN THE WEEK WITH TEMPERATURES TOPPING OUT IN THE UPPER 20S AND LOWER/MID 30S. HOWEVER A DROP INTO THE MID 20S WILL BE FELT LATER IN THE WEEK. OVERNIGHT LOWS IN THE TEENS AND LOWER 20S WILL BE SEEN THROUGH THE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1129 AM CST FRI DEC 18 2015 COLD AIR ALOFT AND LOW LEVEL MOISTURE WILL CONTINUE TO PRODUCE MVFR CEILINGS AND SNOW SHOWERS THIS AFTERNOON INTO THE EVENING. AN AREA OF HIGH PRESSURE WILL THEN BUILD INTO THE NORTHLAND LATER TONIGHT INTO SATURDAY. THE SNOW SHOWERS WILL OCCASIONALLY DROP VSBYS TO IFR. WE DO EXPECT THE MVFR CEILINGS TO GRADUALLY LIFT FROM SOUTHWEST TO NORTHEAST TONIGHT INTO SATURDAY. THERE ARE SOME BREAKS IN THE CLOUDS THAT HAVE DEVELOPED ALREADY THIS AFTERNOON BUT THE RAP SUGGESTS THEY WILL AT LEAST PARTIALLY FILL BACK IN THROUGH THE AFTERNOON BEFORE DISSIPATING AGAIN TONIGHT. GUSTY WEST/NORTHWEST WINDS WILL CONTINUE...THEN DIMINISH TONIGHT. && .PRELIMINARY POINT TEMPS/POPS... DLH 13 7 20 15 / 20 10 0 10 INL 11 3 16 11 / 50 40 10 30 BRD 14 5 21 16 / 10 0 0 10 HYR 16 7 22 16 / 20 10 0 10 ASX 18 11 22 17 / 20 20 10 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...SMALL CRAFT ADVISORY UNTIL 4 AM CST SATURDAY FOR LSZ121-140>148. && $$ SHORT TERM...GRANING LONG TERM...TENTINGER AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS BISMARCK ND
954 PM CST SAT DEC 19 2015 .UPDATE... ISSUED AT 935 PM CST SAT DEC 19 2015 LATEST SATELLITE/RADAR AND SURFACE OBSERVATIONS INDICATE MAINLY MVFR CEILINGS ACROSS FAR NORTHERN NORTH DAKOTA...WITH A PATCH OF IFR CEILINGS OVER NORTHWEST ND INTO NORTHEAST MT. LATEST SURFACE ANALYSIS INDICATES OVERALL WEAK SURFACE PATTERN...BUT LOW PRESSURE OVER SOUTHEAST SASKATCHEWAN...WHICH IS FORECAST TO TRACK SOUTH AND EAST ACROSS THE FORECAST AREA TONIGHT. HAVE ADJUSTED TEMPERATURES LOWER AGAIN...BUT CURRENT T/TD SPREADS ARE CLOSE AND INCREASING WARM ADVECTION/CLOUDS AND POSSIBLY LIGHT SNOW SPREADING WEST TO EAST SHOULD INHIBIT TEMPERATURES FROM FALLING MUCH FARTHER IN THE EAST...WITH STEADY AND SOME RISING TEMPERATURES WEST. LATEST HI RESOLUTION GUIDANCE HAS BACKED OFF ON THE LIGHT PRECIPITATION DROPPING SOUTH AND EAST ACROSS WESTERN NORTH DAKOTA TONIGHT. HOWEVER WE DO SEE AN AREA OF HIGHER REFLECTIVITIES WHICH COULD RESULT IN SOME LIGHT SNOW REACHING THE GROUND...POISED TO MOVE INTO THE WEST SHORTLY. DID FOLLOW THE TREND OF THE LATEST GUIDANCE BUT WITH A MIX OF PERSISTENCE WHICH STILL KEEPS SOME SLIGHT CHANCE POPS DROPPING SOUTH ACROSS MAINLY WESTERN NORTH DAKOTA TONIGHT. UPDATE ISSUED AT 537 PM CST SAT DEC 19 2015 ...QUICK UPDATE FOR EVENING TEMPERATURES... LATEST SATELLITE AND RADAR IMAGERY SHOWS MOSTLY CLOUDY CONDITIONS ACROSS WESTERN AND CENTRAL NORTH DAKOTA WITH MAINLY MID AND HIGH LEVEL CLOUDS. SURFACE LOW PRESSURE REMAINS OVER SOUTHERN SASKATCHEWAN THROUGH EASTERN MONTANA INTO NORTHEAST WYOMING. ENOUGH BREAKS AND THIN SPOTS IN THE CLOUDS LATE THIS AFTERNOON TO ALLOW TEMPERATURES TO QUICKLY DROP OFF. UPDATED OVERNIGHT LOWS STARTING OUT WITH GRIDDED LAMP GUIDANCE WHICH BETTER DEPICTED THE QUICK DROP EARLY THIS EVENING...THEN TRANSITIONED TO A TIME- LAGGED VERSION OF A CONSENSUS OF SHORT RANGE MODELS...SIMILAR TO THE PREVIOUS FORECAST. ALREADY SEEING TEMPERATURES NEARING OVERNIGHT LOWS OVER CENTRAL ND. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 237 PM CST SAT DEC 19 2015 FOG POTENTIAL AND LIGHT SNOW TONIGHT HIGHLIGHT THE SHORT TERM FORECAST. THE 12 THROUGH 19 UTC HRRR ITERATIONS HAVE BEEN VERY CONSISTENT IN SUGGESTING THE POTENTIAL FOR FOG TONIGHT INTO SUNDAY MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA. FOG IS FIST EXPECTED TO FORM ACROSS THE JAMES RIVER VALLEY LATE THIS EVENING WITH INCREASING LOW LEVEL MOISTURE OVER THE SNOWPACK VIA SOUTHEASTERLY WINDS...AND PLUME WESTWARD TOWARDS THE HIGHWAY 83 CORRIDOR. ACROSS THE WEST...BEHIND A WEAK COLD FRONT TONIGHT...STRATUS BUILD DOWN TO FOG IS ALSO SUGGESTED BY THE HRRR. A SIMILAR SCENARIO IS HINTED AT IN THE 12 AND 18 UTC NAM NEST VISIBILITY FORECASTS. A BAND OF LIGHT SNOW IS ALSO POSSIBLE WITH THE AFOREMENTIONED COLD FRONT TONIGHT INTO EARLY SUNDAY MORNING. ANY SNOWFALL AMOUNTS ARE EXPECTED TO REMAIN AS A DUSTING AT BEST. FOR SUNDAY...A COOLER DAY IS EXPECTED ACROSS THE SOUTHWEST WHERE HIGHS IN 40S ARE OCCURRING THIS AFTERNOON WITH WESTERLY WINDS AND A LACK OF SNOWPACK. ELSEWHERE...THE TEMPERATURE CHANGE BEHIND THE WEAK COLD FRONT WILL BE GENERALLY UNNOTICEABLE ON SUNDAY COMPARED TO SATURDAY HIGHS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 237 PM CST SAT DEC 19 2015 RATHER SEASONABLE LATE DECEMBER TEMPERATURES HIGHLIGHT THE EXTENDED FORECAST...WITH A SOMEWHAT UNCERTAIN PRECIPITATION FORECAST. OVERALL...THE 12 UTC GLOBAL DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT ON THE LARGE SCALE PATTERN OF A BROAD...LOW AMPLITUDE UPPER LEVEL CONUS TROUGH FOR MUCH OF THE PERIOD...POSSIBLY TRANSITIONING TO SPLIT FLOW BY NEXT WEEKEND. THIS WOULD SUGGEST RATHER SEASONABLE TEMPERATURES WITH NO SIGNIFICANT WARM UPS OR COOL DOWNS. HOWEVER...THE RATHER FAST...NEAR ZONAL FLOW AT THE BASE OF THE LOW AMPLITUDE TROUGH DOES INJECT UNCERTAINTY IN THE TIMING OF MULTIPLE WAVES AND ASSOCIATED PRECIPITATION EVENTS THROUGH THE PERIOD. THE BEST AGREEMENT IS ON A WEAK WAVE AND POSSIBLE LIGHT SNOW BAND CENTRAL ON MONDAY. HOWEVER...THEREAFTER THE MODEL SPREAD WIDENS IN REGARDS TO SEVERAL POSSIBLE LIGHT SNOWFALL EVENTS LEADING UP TO CHRISTMAS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 935 PM CST SAT DEC 19 2015 IFR CEILINGS CONTINUE AT KISN LATE THIS EVENING ALONG A WEAK WARM FRONT. THINK THE LOW CEILINGS MAY CLEAR KISN IN THE NEXT HOUR OR TWO...BUT WITH MVFR TO POSSIBLY IFR CEILINGS BUILDING IN AGAIN TOWARD 12 UTC. ELSEWHERE...HIRES MODELS HAVE PRETTY MUCH GIVEN UP ON THE LOW STRATUS/FOG ACROSS THE SOUTH CENTRAL AND SOUTHEAST TONIGHT...BUT ALL DO INDICATE AN AREA OF MVFR-IFR CEILINGS DROPPING SOUTHEAST FROM KMOT TO KBIS FROM 06-10 UTC AND POSSIBLY EXPANDING BACK WEST INTO KISN AND KDIK. WILL TAPER BACK ON THE MENTION OF FOG TONIGHT...BUT LEAN MORE TOWARD MVFR CEILINGS REMAINING ACROSS THE WEST AT LEAST THROUGH EARLY AFTERNOON. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...AYD LONG TERM...AYD AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
548 PM CST SAT DEC 19 2015 .UPDATE... ISSUED AT 537 PM CST SAT DEC 19 2015 ...QUICK UPDATE FOR EVENING TEMPERATURES... LATEST SATELLITE AND RADAR IMAGERY SHOWS MOSTLY CLOUDY CONDITIONS ACROSS WESTERN AND CENTRAL NORTH DAKOTA WITH MAINLY MID AND HIGH LEVEL CLOUDS. SURFACE LOW PRESSURE REMAINS OVER SOUTHERN SASKATCHEWAN THROUGH EASTERN MONTANA INTO NORTHEAST WYOMING. ENOUGH BREAKS AND THIN SPOTS IN THE CLOUDS LATE THIS AFTERNOON TO ALLOW TEMPERATURES TO QUICKLY DROP OFF. UPDATED OVERNIGHT LOWS STARTING OUT WITH GRIDDED LAMP GUIDANCE WHICH BETTER DEPICTED THE QUICK DROP EARLY THIS EVENING...THEN TRANSITIONED TO A TIME- LAGGED VERSION OF A CONSENSUS OF SHORT RANGE MODELS...SIMILAR TO THE PREVIOUS FORECAST. ALREADY SEEING TEMPERATURES NEARING OVERNIGHT LOWS OVER CENTRAL ND. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 237 PM CST SAT DEC 19 2015 FOG POTENTIAL AND LIGHT SNOW TONIGHT HIGHLIGHT THE SHORT TERM FORECAST. THE 12 THROUGH 19 UTC HRRR ITERATIONS HAVE BEEN VERY CONSISTENT IN SUGGESTING THE POTENTIAL FOR FOG TONIGHT INTO SUNDAY MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA. FOG IS FIST EXPECTED TO FORM ACROSS THE JAMES RIVER VALLEY LATE THIS EVENING WITH INCREASING LOW LEVEL MOISTURE OVER THE SNOWPACK VIA SOUTHEASTERLY WINDS...AND PLUME WESTWARD TOWARDS THE HIGHWAY 83 CORRIDOR. ACROSS THE WEST...BEHIND A WEAK COLD FRONT TONIGHT...STRATUS BUILD DOWN TO FOG IS ALSO SUGGESTED BY THE HRRR. A SIMILAR SCENARIO IS HINTED AT IN THE 12 AND 18 UTC NAM NEST VISIBILITY FORECASTS. A BAND OF LIGHT SNOW IS ALSO POSSIBLE WITH THE AFOREMENTIONED COLD FRONT TONIGHT INTO EARLY SUNDAY MORNING. ANY SNOWFALL AMOUNTS ARE EXPECTED TO REMAIN AS A DUSTING AT BEST. FOR SUNDAY...A COOLER DAY IS EXPECTED ACROSS THE SOUTHWEST WHERE HIGHS IN 40S ARE OCCURRING THIS AFTERNOON WITH WESTERLY WINDS AND A LACK OF SNOWPACK. ELSEWHERE...THE TEMPERATURE CHANGE BEHIND THE WEAK COLD FRONT WILL BE GENERALLY UNNOTICEABLE ON SUNDAY COMPARED TO SATURDAY HIGHS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 237 PM CST SAT DEC 19 2015 RATHER SEASONABLE LATE DECEMBER TEMPERATURES HIGHLIGHT THE EXTENDED FORECAST...WITH A SOMEWHAT UNCERTAIN PRECIPITATION FORECAST. OVERALL...THE 12 UTC GLOBAL DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT ON THE LARGE SCALE PATTERN OF A BROAD...LOW AMPLITUDE UPPER LEVEL CONUS TROUGH FOR MUCH OF THE PERIOD...POSSIBLY TRANSITIONING TO SPLIT FLOW BY NEXT WEEKEND. THIS WOULD SUGGEST RATHER SEASONABLE TEMPERATURES WITH NO SIGNIFICANT WARM UPS OR COOL DOWNS. HOWEVER...THE RATHER FAST...NEAR ZONAL FLOW AT THE BASE OF THE LOW AMPLITUDE TROUGH DOES INJECT UNCERTAINTY IN THE TIMING OF MULTIPLE WAVES AND ASSOCIATED PRECIPITATION EVENTS THROUGH THE PERIOD. THE BEST AGREEMENT IS ON A WEAK WAVE AND POSSIBLE LIGHT SNOW BAND CENTRAL ON MONDAY. HOWEVER...THEREAFTER THE MODEL SPREAD WIDENS IN REGARDS TO SEVERAL POSSIBLE LIGHT SNOWFALL EVENTS LEADING UP TO CHRISTMAS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 537 PM CST SAT DEC 19 2015 THE LAST COUPLE ITERATIONS OF THE HRRR AND EXP-HRRR HAVE BACKED OFF ON THE EXTENT OF LOW STRATUS OVER THE FAR SOUTH CENTRAL AND JAMES RIVER VALLEY THAT WERE DEPICTED BY EARLIER RUNS. HAVE BACKED OFF A LITTLE ON THE MENTION OF FOG AND DELAYED IT UNTIL 06 UTC. HI-RES MODELS DEVELOP FOG OVER THE SNOWPACK AROUND 01-03 UTC TONIGHT SO WE SHOULD HOPEFULLY GET A BETTER IDEA ON THE PROBABILITY OF FOG OVER CENTRAL ND IN THE NEXT FEW HOURS. STILL LOOKS LIKE A POSSIBILITY OF MVFR-IFR CEILINGS AND VISIBILITIES BEHIND THE COLD FRONT THAT MOVES INTO THE NORTHWEST LATER THIS EVENING. CONDITIONS IMPROVE FROM WEST TO EAST DURING THE MORNING HOURS ON SUNDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...AYD LONG TERM...AYD AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1235 AM CST FRI DEC 18 2015 .UPDATE... ISSUED AT 1235 AM CST FRI DEC 18 2015 LIGHT SNOW AND FLURRIES CONTINUED OVER PARTS OF CENTRAL NORTH DAKOTA...LIKELY ASSOCIATED WITH THE UPPER LEVEL SHORTWAVE MOVING SOUTHEAST ACROSS CENTRAL AND EASTERN NORTH DAKOTA. THE PREVIOUS UPDATE DISCUSSION NOTED THE LAKE-INDUCED BAND OF SNOW SHOWERS FROM WASHBURN AREA AND SOUTHEASTWARD. HAVE EXPANDED MENTION OF SLIGHT CHANCE/CHANCE OF LIGHT SNOW AND FLURRIES FOR THE OVERNIGHT HOURS...DIMINISHING WITH TIME AS THE SHORTWAVE EXITS TO THE SOUTHEAST TOWARDS DAYBREAK. THE VARIABLE CLOUD COVER - WITH TEMPS MAINLY IN THE TEENS BELOW...AND TEMPS IN THE SINGLE DIGITS UNDER CLEAR SKIES - HAS MADE FOR TRICKY HOURLY TEMPERATURE TRENDS. HOWEVER AS SKIES CLEAR WITH TIME EXPECT MORNING LOWS FROM JUST BELOW ZERO TO AROUND 5-7 ABOVE. UPDATE ISSUED AT 927 PM CST THU DEC 17 2015 LIGHT SNOW SHOWER AND FLURRY ACTIVITY WILL GRADUALLY END AFTER 06 UTC AS A WEAK SHORTWAVE TROUGH EXITS INTO SD AND LOW-LEVEL WINDS DECREASE...REDUCING THE EFFICIENCY OF SNOW SHOWER PRODUCTION PER A MODEL-SIMULATED DROP IN SNOW SQUALL PARAMETER VALUES. WE CHOSE TO LINGER SOME FLURRY ACTIVITY A BIT LONGER PAST MIDNIGHT ACROSS SOUTH CENTRAL ND AND REFINED POPS THROUGH THE NEXT SEVERAL HOURS WITH THIS UPDATE BASED ON RECENT HRRR AND RADAR TRENDS...WHICH MOST NOTABLY DEPICT A LAKE-INDUCED BAND OF SNOW SHOWERS FROM RIVERDALE TOWARD UNDERWOOD...WASHBURN AND WILTON AS OF 0315 UTC. UPDATE ISSUED AT 558 PM CST THU DEC 17 2015 WE ARE CONTINUING A MENTION OF SNOW SHOWERS AND FLURRIES THROUGH THIS EVENING ACROSS MUCH OF THE AREA...WITH THE HIGHEST /20 TO 30/ POPS OVER SOUTHWEST AND SOUTH CENTRAL ND. THAT AREA IS WHERE THE SNOW SQUALL PARAMETER FROM THE 18 UTC NAM AND 20-22 UTC RAP RUNS IS GREATEST BOTH DUE TO INFLUENCE FROM A WEAK SHORTWAVE TROUGH AND POSSIBLE LAKE EFFECT ENHANCEMENT DOWNWIND OF LAKE SAKAKAWEA. BRIEF REDUCTIONS IN VISIBILITY ARE POSSIBLE WITH ANY SNOW SHOWERS...AS NOTED IN DICKINSON...WHERE VISIBILITY FELL TO 2SM FOR A TIME. THE REST OF THE FORECAST IS LARGELY ON-TRACK AND WAS BLENDED TO RECENT OBSERVED TRENDS AND SHORT-RANGE MODEL GUIDANCE. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 245 PM CST THU DEC 17 2015 CHALLENGE FOR THE SHORT TERM WILL BE THE CLOUDS AND SNOW SHOWERS/FLURRIES THAT COMPLICATE THE AFTERNOON AND EVENING PERIOD. COLD CYCLONIC FLOW ALOFT LIKELY SUPPORTING SLANTWISE INSTABILITY SNOW SHOWERS ACROSS THE NORTH CENTRAL AND EAST THIS AFTERNOON INTO THIS EVENING. SECOND...LAKE EFFECT SNOW FLURRIES HAVE POPPED UP FROM THE VAN HOOK ARM TO BISMARCK AND WILL CONTINUE THROUGH EARLY EVENING. FINALLY...A BAND OF SNOW SHOWERS SHOWING UP ACROSS NORTHEAST MONTANA ASSOCIATED WITH STRONG NORTHWEST MID LEVEL FLOW WILL TRACK ACROSS SOUTHWEST/SOUTH CENTRAL NORTH DAKOTA THIS EVENING. BUFKIT SOUNDINGS FOR KBIS SHOW LOW LEVEL SATURATION IN THE DENDRITIC GROWTH ZONE THAT SHOULD SUPPORT SNOW FLAKE GROWTH. TONIGHT THE PRECIP WILL END AFTER MIDNIGHT. AS TEMPERATURES DROP WIND CHILLS WILL DIP TO NEAR 25 BELOW NORTH CENTRAL FOR A FEW MORNING HOURS. WILL MENTION IN THE HWO BUT DO NOT BELIEVE THE COLD WIND CHILLS WILL LAST MORE THAN A FEW HOURS. ON FRIDAY...AN APPROACHING H500 RIDGE AND THE H500 DEPARTING COLD LOW OVER THE GREAT LAKES SHOULD GIVE THE REGION A COOL AND QUIET DAY. WINDS WILL DIMINISH WITH GENERALLY SUNNY SKIES. HIGHS WILL BE SINGLE DIGITS NORTH CENTRAL TO THE LOWER 20S SOUTHWEST. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 245 PM CST THU DEC 17 2015 A RELATIVELY QUIET PERIOD EARLY THIS WEEKEND BECOMES MORE ACTIVE LATE THIS WEEKEND AND THROUGH THE CHRISTMAS HOLIDAY. UPPER LEVEL RIDGING ACROSS THE GREAT PLAINS WILL RESULT IN SURFACE HIGH PRESSURE SLIDING SOUTH-SOUTHEAST FROM THE CENTRAL DAKOTAS INTO THE MIDWEST ALLOWING RETURN FLOW AND WAA TO DEVELOP OVER THE WESTERN DAKOTAS. OVERNIGHT LOWS FRIDAY NIGHT/SAT MORNING WILL REFLECT THIS...SUBZERO EAST TO ABOVE ZERO WEST. WARMING TREND FOR SATURDAY WITH NEAR NORMAL DAYTIME HIGHS FORECAST FROM THE 30S SOUTHWEST AND 20S CENTRAL. A FEW TEENS STILL PROBABLE EAST. TEMPERATURES WILL BE TEMPERED BY OUR EXISTING SNOW COVER...WHICH COULD BE 10+ DEGREES WARMER IF THE GROUND WAS BARE. SERIES OF S/WV TROUGHS WILL BE STEERED ACROSS THE NORTHERN PLAINS SUNDAY AND ONWARDS...BRINGING OFF AND ON PERIODS OF PRECIPITATION...GENERALLY IN THE FORM OF SNOW GIVEN MODEL SUGGESTED THERMAL PROFILES. DUE TO THE SMALL SCALE OF THESE FEATURES...IT IS VERY DIFFICULT AT THIS TIME TO PINPOINT SPECIFICS...WITH A BIG SPREAD OF MODEL SOLUTIONS. GIVEN CHRISTMAS TRAVEL FOR MANY NEXT WEEK...WILL MENTION THIS POSSIBLE ACTIVE FLOW PERIOD IN THE HWO TO HIGHLIGHT THE POTENTIAL FOR ADVERSE WEATHER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1235 AM CST FRI DEC 18 2015 A MIX OF VFR AND MVFR CEILINGS IS LIKELY THROUGH 12Z. LOCALLY- REDUCED VISIBILITIES ARE ALSO POSSIBLE WITH A FEW SNOW SHOWERS IN SOUTH CENTRAL ND THROUGH ABOUT 10 UTC. KEPT THE TEMPO GROUP FOR CIGS BUT CONFIDENCE NOT HIGH ENOUGH TO MENTION REDUCED VSBYS AT TAF SITES. VFR WEATHER WILL BECOME PREVALENT AT ALL TAF SITES AFT 12Z AS HIGH PRESSURE BUILDS INTO THE AREA. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JV SHORT TERM...WAA LONG TERM...NH AVIATION...JV
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
657 AM EST FRI DEC 18 2015 .SYNOPSIS... A COLD FRONT WILL MOVE EAST OF THE AREA THIS AFTERNOON WITH LAKE EFFECT SNOW DEVELOPING BEHIND THE FRONT IN THE SNOWBELT. HIGH PRESSURE WILL BRIEFLY BUILD OVER THE REGION SATURDAY NIGHT AND SUNDAY BEFORE ANOTHER FRONT ENTERS THE REGION ON MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... ONLY MINOR CHANGES MADE TO THE CLOUD COVER THIS MORNING AND POPS THROUGH ABOUT NOONTIME. SATELLITE IMAGERY SHOWERS SOME BREAKS IN THE CLOUDS OVER ILLINOIS AND INDIANA WHICH MAY MOVE INTO THE REGION THIS MORNING. HAVE ALSO DELAYED THE INCREASE IN POPS THIS MORNING NEAR THE LAKE SHORE GIVEN THE RATHER CLEAR RADAR MOSAIC CURRENTLY SHOWN AND MINIMAL PREDICTION FROM THE HRRR OF REFLECTIVITY/PCPN EXCEPT NEAR THE LAKE SHORE FROM NEAR MENTOR NORTHEAST UP THE SHORE TO ERIE. CURRENT MAX TEMPERATURE FORECAST LOOKS REASONABLE. PREVIOUS DISCUSSION... A SEASONABLY COOL DAY IS IN STORE FOR THE REGION AS A DIFFUSE COLD FRONT CROSSES THE REGION THIS MORNING AND COLD ADVECTION IN ITS WAKE BEGINS TO SET THE STAGE FOR THE FIRST LAKE EFFECT SNOW WARNING OF THE SEASON IN NORTHWEST PENNSYLVANIA. INITIALLY FOR TODAY EXPECT VARIABLE TO MOSTLY CLOUDY SKIES WITH A GRADUAL INCREASE IN THE CHANCE FOR SNOW SHOWERS OVER THE LAKE AND SNOWBELT COUNTIES MAINLY THIS AFTERNOON AND MORE SO TOWARD EVENING. HAVE LOWERED POPS FROM THE PREVIOUS FORECAST FOR THIS MORNING AS LITTLE IF ANY LIFT IS EXPECTED. MAX TEMPERATURES WILL ONLY REACH THE MID TO UPPER 30S. SNOW SHOWERS COULD ACCUMULATE AN INCH OR SO BY EVENING IN NORTHWEST PENNSYLVANIA WITH LESSOR AMOUNTS IN THE OHIO SNOWBELT. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... HAVE KEPT THE HEADLINES THE SAME FROM THE PREVIOUS FORECAST WITH THE EXPECTATION THAT WARNING AMOUNTS OF LAKE EFFECT SNOW WILL FALL OVER ERIE COUNTY PENNSYLVANIA TONIGHT AND SATURDAY. THE DEPTH OF THE MIXED LAYER WILL QUICKLY INCREASE THIS EVENING ACROSS THE LAKE SHORE WITH NO INVERSION PRESENT FOR SEVERAL HOURS OVERNIGHT. CONSEQUENTLY...A RATHER DEEP AND MOIST MIXED LAYER EXTENDING ABOVE 10000 FEET WILL DEVELOP OVER AND NEAR THE LAKESHORE. LAKE INDUCED INSTABILITY OR CAPE IS RATHER IMPRESSIVE FROM 700-900 J/KG AND GIVEN THAT LAKE ERIE IS ABOUT 8C ABOVE NORMAL AND THAT 500 MB TEMPERATURES WILL DROP TO ABOUT -35C....SUFFICIENT TEMPERATURE DIFFERENTIAL WILL EXIST TO PRODUCE THUNDERSNOW OVER THE LAKE AND NORTHWEST PA. CLIMATOLOGICALLY, WHEN LAKE ERIE IS WARMER THAN 5C THE LIKELIHOOD OF GRAUPEL AND IS ENHANCED (ALONG WITH THUNDERSNOW) SO WE SHOULD SEE PLENTY OF IT TONIGHT. THE TEMPERATURE INVERSION IS EXPECTED DEVELOP AND LOWER ON SATURDAY AND SUPPRESS THE LAKE EFFECT SNOW ESPECIALLY IN THE AFTERNOON. WILL KEEP THE LAKE EFFECT SNOW ADVISORY IN PLACE OUTSIDE OF ERIE COUNTY SINCE THERE IS SOME CONCERN THAT THE WESTERLY FLOW MAY A TIMES BECOME WSWLY AT 260-250 DEGREES WITH CONVERGENCE ON THE SOUTH SIDE OF THE BAND THAT MAY LIMIT ITS SOUTHWARD MOVEMENT INTO ASHTABULA AND CRAWFORD COUNTIES. GRADUAL IMPROVEMENT IN THE WEATHER WILL CONTINUE SUNDAY EVENING AS THE FLOW BECOMES SOUTHWESTERLY AND ALLOWS ANY LINGER SNOW BANDS TO MIGRATE UP THE LAKE AND PERMIT CLEARING TO OVERSPREAD THE REGION. && .LONG TERM /MONDAY THROUGH THURSDAY/... THE MODELS ARE SOMEWHAT MORE PROGRESSIVE IN THE EXTENDED PORTION OF THE FORECAST. THE WEAKENING COLD FRONT IS PROGGED TO SLIDE ACROSS THE AREA ON MONDAY. SOME OF THE MODELS ARE FAST WITH THE SHOWERS MOVING ACROSS THE AREA ON MONDAY...BUT THE TIMING OF THE FRONT IS NOT ANY FASTER. WILL KEEP A CHANCE OF SHOWERS ALL DAY MONDAY UNTIL THE FRONT COMES THROUGH. THE FRONT IS PROGGED TO STALL JUST TO THE SOUTH ON MONDAY NIGHT. IT MAY TAKE UNTIL TUESDAY NIGHT OR WEDNESDAY TO COME BACK NORTH AS A WARM FRONT. NUDGED DOWN THE FORECAST POPS ON TUESDAY TO GENERALLY 20-30 (SLIGHT CHANCE/CHANCE) WITH HIGHER POPS TUESDAY NIGHT AND WEDNESDAY AS THE WARM FRONT LIFTS NORTH. THE NEXT COLD FRONT IS EXPECTED ON CHRISTMAS EVE. THE LATEST MODEL RUNS ARE FASTER WITH THE FRONT. IT MAY BE EAST OF THE AREA SOMETIME THURSDAY MORNING. IT IS POSSIBLE THAT WE COULD HAVE A MORNING MAX BUT THE AIR MASS BEHIND THE FRONT IS NOT ALL THAT COLD AND WILL NOT TRY TO GET ALL THAT SPECIFIC SEVEN DAYS OUT. NONETHELESS...THERE IS SOME UNCERTAINTY ON THE TEMPS AND POPS ON CHRISTMAS EVE DEPENDING ON THE TIMING OF THE FRONT. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... CEILINGS HAVE RISEN TO VFR FOR MUCH OF THE AREA ALTHOUGH PATCHES OF MVFR (BKN024-BKN030) STRATOCUMULUS LINGER. VFR CLOUDS WILL LIKELY PERSIST MOST OF TODAY. A COLD FRONT WILL CROSS THE AREA WEST TO EAST MIDDAY AND AFTERNOON. A FEW SNOW SHOWERS/FLURRIES WILL OCCUR WITH THE FRONT BUT ANY SNOW SHOWERS OF ANY SIGNIFICANCE WILL BE BRIEF AND SHOULD NOT PRESENT A MAJOR AVIATION ISSUE. THE EXCEPTION WILL BE NEAR LAKE ERIE AROUND KERI WHERE LAKE EFECT SNOW WILL BE HEAVIER. MVFR AND IFR VISIBILITIES WILL DEVELOP LATE AFTERNOON AND CONTINUE TONIGHT AT KERI AND ACROSS THE SNOWBELT OF EXTREME NORTHEAST OH AND NORTHWEST PA. OUTLOOK...NON VFR EXTREME NE OHIO AND NW WEST PA SAT INTO SAT NIGHT IN LAKE EFFECT SNOW SHOWERS. NON VFR POSSIBLE ON MONDAY. && .MARINE... MADE SOME MINOR CHANGES WITH THE SMALL CRAFT ADVISORY. WINDS ARE CURRENTLY LIGHT TO MODERATE SOUTHWEST ACROSS THE WESTERN HALF OF THE LAKE WITH WAVES UNDER 4 FEET. A COLD FRONT WILL CROSS THE LAKE FROM WEST TO EAST LATE THIS MORNING AND THIS AFTERNOON AND WINDS AND WAVES WILL PICK BACK UP. STARTED THE SMALL CRAFT ADVISORY FOR ALL OF WESTERN LAKE ERIE THIS AFTERNOON. KEPT THE SMALL CRAFT ADVISORY FROM CLEVELAND EAST BASED ON THE CURRENT WINDS OF 15 TO 20 KNOTS FROM THE NORTHWEST. WINDS AND WAVES COULD DROP BELOW SMALL CRAFT CRITERIA FOR A FEW HOURS THIS MORNING BUT DID NOT WANT TO TAKE DOWN THE SMALL CRAFT ADVISORY FOR SUCH A SHORT INTERVAL WITHOUT BETTER CONFIDENCE THAT WE CAN GET THE LAKE TO SETTLE DOWN. WINDS AND WAVES WILL SETTLE DOWN SATURDAY NIGHT AS HIGH PRESSURE BUILDS ACROSS THE OHIO VALLEY. THE SOUTH TO SOUTHWEST FLOW WILL PICK BACK UP QUICKLY DURING THE DAY SUNDAY AND SUNDAY NIGHT AHEAD OF THE NEXT COLD FRONT. THE NEXT COLD FRONT WILL CROSS THE LAKE ON MONDAY WITH WINDS AND WAVES BUILDING AGAIN. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 10 PM EST SATURDAY FOR OHZ012-014-089. PA...LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 10 PM EST SATURDAY FOR PAZ003. LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 10 PM EST SATURDAY FOR PAZ001-002. MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST SUNDAY FOR LEZ146>149. SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 9 PM EST SATURDAY FOR LEZ142>145. && $$ SYNOPSIS...LAPLANTE NEAR TERM...LAPLANTE/OUDEMAN SHORT TERM...LAPLANTE LONG TERM...KOSARIK AVIATION...KOSARIK MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
630 AM EST FRI DEC 18 2015 .SYNOPSIS... A COLD FRONT WILL MOVE EAST OF THE AREA THIS AFTERNOON WITH LAKE EFFECT SNOW DEVELOPING BEHIND THE FRONT IN THE SNOWBELT. HIGH PRESSURE WILL BRIEFLY BUILD OVER THE REGION SATURDAY NIGHT AND SUNDAY BEFORE ANOTHER FRONT ENTERS THE REGION ON MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... ONLY MINOR CHANGES MADE TO THE CLOUD COVER THIS MORNING AND POPS THROUGH ABOUT NOONTIME. SATELLITE IMAGERY SHOWERS SOME BREAKS IN THE CLOUDS OVER ILLINOIS AND INDIANA WHICH MAY MOVE INTO THE REGION THIS MORNING. HAVE ALSO DELAYED THE INCREASE IN POPS THIS MORNING NEAR THE LAKE SHORE GIVEN THE RATHER CLEAR RADAR MOSAIC CURRENTLY SHOWN AND MINIMAL PREDICTION FROM THE HRRR OF REFLECTIVITY/PCPN EXCEPT NEAR THE LAKE SHORE FROM NEAR MENTOR NORTHEAST UP THE SHORE TO ERIE. CURRENT MAX TEMPERATURE FORECAST LOOKS REASONABLE. PREVIOUS DISCUSSION... A SEASONABLY COOL DAY IS IN STORE FOR THE REGION AS A DIFFUSE COLD FRONT CROSSES THE REGION THIS MORNING AND COLD ADVECTION IN ITS WAKE BEGINS TO SET THE STAGE FOR THE FIRST LAKE EFFECT SNOW WARNING OF THE SEASON IN NORTHWEST PENNSYLVANIA. INITIALLY FOR TODAY EXPECT VARIABLE TO MOSTLY CLOUDY SKIES WITH A GRADUAL INCREASE IN THE CHANCE FOR SNOW SHOWERS OVER THE LAKE AND SNOWBELT COUNTIES MAINLY THIS AFTERNOON AND MORE SO TOWARD EVENING. HAVE LOWERED POPS FROM THE PREVIOUS FORECAST FOR THIS MORNING AS LITTLE IF ANY LIFT IS EXPECTED. MAX TEMPERATURES WILL ONLY REACH THE MID TO UPPER 30S. SNOW SHOWERS COULD ACCUMULATE AN INCH OR SO BY EVENING IN NORTHWEST PENNSYLVANIA WITH LESSOR AMOUNTS IN THE OHIO SNOWBELT. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... HAVE KEPT THE HEADLINES THE SAME FROM THE PREVIOUS FORECAST WITH THE EXPECTATION THAT WARNING AMOUNTS OF LAKE EFFECT SNOW WILL FALL OVER ERIE COUNTY PENNSYLVANIA TONIGHT AND SATURDAY. THE DEPTH OF THE MIXED LAYER WILL QUICKLY INCREASE THIS EVENING ACROSS THE LAKE SHORE WITH NO INVERSION PRESENT FOR SEVERAL HOURS OVERNIGHT. CONSEQUENTLY...A RATHER DEEP AND MOIST MIXED LAYER EXTENDING ABOVE 10000 FEET WILL DEVELOP OVER AND NEAR THE LAKESHORE. LAKE INDUCED INSTABILITY OR CAPE IS RATHER IMPRESSIVE FROM 700-900 J/KG AND GIVEN THAT LAKE ERIE IS ABOUT 8C ABOVE NORMAL AND THAT 500 MB TEMPERATURES WILL DROP TO ABOUT -35C....SUFFICIENT TEMPERATURE DIFFERENTIAL WILL EXIST TO PRODUCE THUNDERSNOW OVER THE LAKE AND NORTHWEST PA. CLIMATOLOGICALLY, WHEN LAKE ERIE IS WARMER THAN 5C THE LIKELIHOOD OF GRAUPEL AND IS ENHANCED (ALONG WITH THUNDERSNOW) SO WE SHOULD SEE PLENTY OF IT TONIGHT. THE TEMPERATURE INVERSION IS EXPECTED DEVELOP AND LOWER ON SATURDAY AND SUPPRESS THE LAKE EFFECT SNOW ESPECIALLY IN THE AFTERNOON. WILL KEEP THE LAKE EFFECT SNOW ADVISORY IN PLACE OUTSIDE OF ERIE COUNTY SINCE THERE IS SOME CONCERN THAT THE WESTERLY FLOW MAY A TIMES BECOME WSWLY AT 260-250 DEGREES WITH CONVERGENCE ON THE SOUTH SIDE OF THE BAND THAT MAY LIMIT ITS SOUTHWARD MOVEMENT INTO ASHTABULA AND CRAWFORD COUNTIES. GRADUAL IMPROVEMENT IN THE WEATHER WILL CONTINUE SUNDAY EVENING AS THE FLOW BECOMES SOUTHWESTERLY AND ALLOWS ANY LINGER SNOW BANDS TO MIGRATE UP THE LAKE AND PERMIT CLEARING TO OVERSPREAD THE REGION. && .LONG TERM /MONDAY THROUGH THURSDAY/... THE MODELS ARE SOMEWHAT MORE PROGRESSIVE IN THE EXTENDED PORTION OF THE FORECAST. THE WEAKENING COLD FRONT IS PROGGED TO SLIDE ACROSS THE AREA ON MONDAY. SOME OF THE MODELS ARE FAST WITH THE SHOWERS MOVING ACROSS THE AREA ON MONDAY...BUT NOT ANY FASTER WITH THE FRONT. WILL KEEP A CHANCE OF SHOWERS ALL DAY MONDAY UNTIL THE FRONT COMES THROUGH. THE FRONT IS PROGGED TO STALL JUST TO THE SOUTH ON MONDAY NIGHT. IT MAY TAKE UNTIL TUESDAY NIGHT OR WEDNESDAY TO COME BACK NORTH AS A WARM FRONT. NUDGED DOWN THE FORECAST POPS ON TUESDAY TO GENERALLY 20-30 (SLIGHT CHANCE/CHANCE) WITH HIGHER POPS TUESDAY NIGHT AND WEDNESDAY AS THE WARM FRONT LIFTS NORTH. THE NEXT COLD FRONT IS EXPECTED ON CHRISTMAS EVE. THE LATEST MODEL RUNS ARE FASTER WITH THE FRONT. IT MAY BE EAST OF THE AREA SOMETIME THURSDAY MORNING. IT IS POSSIBLE THAT WE COULD HAVE A MORNING MAX BUT THE AIR MASS BEHIND THE FRONT IS NOT ALL THAT COLD AND WILL NOT TRY TO GET ALL THAT SPECIFIC SEVEN DAYS OUT. NONETHELESS...THERE IS SOME UNCERTAINTY ON THE TEMPS AND POPS ON CHRISTMAS EVE DEPENDING ON THE TIMING OF THE FRONT. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... MVFR CEILINGS REMAIN OVER THE EASTERN 2/3RDS OF THE REGION. WESTERN AREAS HAVE LIFTED TO LOW END VFR. EXPECT TO SEE THE ALL LOCATIONS SLOWLY LIFT THROUGH THE OVERNIGHT HOURS WITH A FEW MORE LOCATIONS LIFTING TO LOW END VFR. SOUTHWESTERLY WINDS WILL BE 5 TO 10 KNOTS OVERNIGHT. AS THE NEXT SURGE OF COLDER AIR ARRIVES ON FRIDAY WINDS WILL INCREASE FROM THE SOUTHWEST AND WEST AROUND 15 KNOTS WITH GUST 20 TO 30 KNOTS. THE STRONGEST GUSTS WILL BE NEAR THE LAKESHORE. THERE IS SLIGHT CONCERN THAT SOME LIGHT PRECIPITATION MAY DEVELOP OFF OF LAKE ERIE ACROSS EXTREME NE OHIO INTO NW PA OVERNIGHT. INLAND LOCATIONS MAY SEE SOME FREEZING DRIZZLE OR FLURRIES. OTHERWISE AS THE COLDER AIR ARRIVES ON FRIDAY THERE COULD BE SOME FLURRIES OR BRIEF LIGHT SNOW. THE BETTER CHANCES FOR LAKE EFFECT SNOW WILL BE AFTER SUNSET FRIDAY EVENING. OUTLOOK...NON VFR NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA THRU SAT NIGHT IN LAKE EFFECT SNOW SHOWERS. NON VFR POSSIBLE ON MONDAY. && .MARINE... MADE SOME MINOR CHANGES WITH THE SMALL CRAFT ADVISORY. WINDS ARE CURRENTLY LIGHT TO MODERATE SOUTHWEST ACROSS THE WESTERN HALF OF THE LAKE WITH WAVES UNDER 4 FEET. A COLD FRONT WILL CROSS THE LAKE FROM WEST TO EAST LATE THIS MORNING AND THIS AFTERNOON AND WINDS AND WAVES WILL PICK BACK UP. STARTED THE SMALL CRAFT ADVISORY FOR ALL OF WESTERN LAKE ERIE THIS AFTERNOON. KEPT THE SMALL CRAFT ADVISORY FROM CLEVELAND EAST BASED ON THE CURRENT WINDS OF 15 TO 20 KNOTS FROM THE NORTHWEST. WINDS AND WAVES COULD DROP BELOW SMALL CRAFT CRITERIA FOR A FEW HOURS THIS MORNING BUT DID NOT WANT TO TAKE DOWN THE SMALL CRAFT ADVISORY FOR SUCH A SHORT INTERVAL WITHOUT BETTER CONFIDENCE THAT WE CAN GET THE LAKE TO SETTLE DOWN. WINDS AND WAVES WILL SETTLE DOWN SATURDAY NIGHT AS HIGH PRESSURE BUILDS ACROSS THE OHIO VALLEY. THE SOUTH TO SOUTHWEST FLOW WILL PICK BACK UP QUICKLY DURING THE DAY SUNDAY AND SUNDAY NIGHT AHEAD OF THE NEXT COLD FRONT. THE NEXT COLD FRONT WILL CROSS THE LAKE ON MONDAY WITH WINDS AND WAVES BUILDING AGAIN. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 10 PM EST SATURDAY FOR OHZ012-014-089. PA...LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 10 PM EST SATURDAY FOR PAZ003. LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 10 PM EST SATURDAY FOR PAZ001-002. MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST SUNDAY FOR LEZ146>149. SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 9 PM EST SATURDAY FOR LEZ142>145. && $$ SYNOPSIS...LAPLANTE NEAR TERM...LAPLANTE/OUDEMAN SHORT TERM...LAPLANTE LONG TERM...KOSARIK AVIATION...MULLEN MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
321 PM EST FRI DEC 18 2015 .SYNOPSIS... A DEEP BUT FLEETING 500MB TROUGH IS MOVING THROUGH THE REGION BRINGING US A TOUCH OF WINTER. THIS WILL INCLUDE A LAKE EFFECT SNOW EVENT IN NORTHWESTERN PENNSYLVANIA AND SOUTHWESTERN NEW YORK FRIDAY NIGHT INTO SATURDAY. A 500MB RIDGE WILL MOVE OVER THE REGION SUNDAY TO MONDAY AND MOVE OVER THE WESTERN ATLANTIC. A REBOUND WARM-UP IS FORECAST FOR SUNDAY-WEDNESDAY. BUT MOIST FLOW ABOUT THE MASSIVE RIDGE COULD BRING RAIN INTO THE REGION BY CHRISTMAS EVE. ABOVE NORMAL TEMPERATURES ARE EXPECTED FOR MOST OF THE COMING WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... COLD AIR CONTINUES TO MOVE ACROSS THE REGION AND THE WINDS HAVE BECOME A BIT GUSTY. THE CLOUDS WITH THE SECOND SURGE OF COLD AIR HAVE PUSHED INTO THE LOWER SUSQUEHANNA VALLEY. THE DAY WILL END CLOUDY TO MOSTLY CLOUDY. THE 0000 UTC 3KM NCAR ENSEMBLE SUGGESTED SNOW SHOWERS WOULD MOVE INTO WESTERN PENNSYLVANIA LATER THIS EVENING. THE NEW 16Z HRRR IS NOW SHOWING MEASURABLE SNOW AFTER 8 PM TONIGHT WHICH IS THE NEXT PERIOD. SOME MINOR POCKETS OF ISOLATED SNOW SHOWERS ARE IMPLIED IN THE HRRR IN THE LAURELS. MOSTLY CLOUDY AND BREEZY WILL BE THE MAIN WEATHER TODAY...SEASONABLY COLD FOR A NORMAL DECEMBER COLD FOR THE WARM DECEMBER OF 2015. SOME SNOW FLURRIES POSSIBLE IN THE NORTHERN AND WESTERN MOUNTAINS. BRIEF AND INTERMITTENT SNOW SHOWERS ARE POSSIBLE IN THE MOUNTAINS THIS AFTERNOON WHICH COULD COAT THE GROUND LATER THIS AFTERNOON AND EVENING. && .SHORT TERM /8 PM THIS EVENING THROUGH SATURDAY NIGHT/... *SIGNIFICANT LAKE EFFECT SNOW ACROSS THE NORTHWEST PA SNOWBELT FRIDAY NIGHT AND SATURDAY* THE 3KM HRRR NOW CAPTURES THE ONSET OF THE SNOW EVENT. INITIALLY IT KEEPS THE MAIN BAND NORTH OF THE PA/NY BORDER. IT DOES SHOW SOME MEASURABLE SNOW BY 10 PM THROUGH 2AM. A FEW INCHES. THE HRRR HAS AN INTENSE BAND OF HEAVY SNOW AT THIS TIME IN NY STATE...THIS BAND HAS 0.50 TO 0.70 INCHES OF QPF...THAT IS A LOT OF LES POTENTIAL. HOPEFULLY IT ALL STAYS IN NY. BASED ON THE HRRR...PREVIOUS NCAR EFS KEPT OUR SNOW IN THE 5-8 RANGE IN EXTREME NORTHERN WARREN COUNTY AND LOWER TO SOUTH AND WEST. ALSO SHOWED SOME SNOW IN THE LAURELS. WE WILL HAVE TO MONITOR THE HRRR FOR THE BIGGER BAND SHOULD IT TREND SOUTH. MOST OTHER AREAS COULD SEE SOME SNOW FLURRIES OVERNIGHT AND EARLY SATURDAY. IT SHOULD BECOME QUITE BREEZY SATURDAY IN THE COLD AIR. SOME GUIDANCE SHOWS CLOSE TO ADVISORY CATEGORY GUSTS IN THE SOUTHWEST MOUNTAINS SATURDAY AFTERNOON. PREVIOUS INFORMATION ON NCAR ENSEMBLE FORECAST... THE NCAR 3KM ENSEMBLE SHOWS THAT THE FIRST INCH OF SNOW AT THE 90 PERCENT CONFIDENCE LEVEL FALLS IN NORTHERN WARREN COUNTY BY ABOUT 9 PM. THE 3 INCH VALUES ARE REACHED BY ABOUT 8 AM SATURDAY. THE 6 INCH PROBABILITY AT 80 PERCENT OUR GREATER MOVES IN AROUND 10 AM AND PEAKING NEAR 100 PERCENT BY 3-4 PM. BEST CHANCE ACROSS NORTHERN AREAS OF WARREN COUNTY. THERE IS A 10 PERCENT CHANCE OF 1 FOOT OF SNOW IN A SLIVER OF NORTHWESTERN WARREN COUNTY. VERY LOW CHANCE OF A FOOT IN THE 3KM MODELS. && .LONG TERM /SUNDAY THROUGH THURSDAY/... A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT WILL DRIFT EAST ACROSS THE COMMONWEALTH ON SUNDAY...ACCOMPANIED BY A SLIGHT MODERATION IN TEMPERATURES AND LIGHTER WINDS. TEMPERATURES WILL CONTINUE TO REBOUND ON MONDAY...AS WARM AIR FROM THE SOUTH FILTERS INTO THE REGION AHEAD OF A COLD FRONT. THE COLD FRONT WILL PUSH ACROSS THE STATE LATE MONDAY INTO TUESDAY...BRINGING SCATTERED SHOWERS. MODELS STILL HAVE SOME TIMING VARIATIONS...BUT RAINFALL SHOULD BE LIMITED AND MOST LOCATIONS WILL SEE NO MORE THAN A FEW TENTHS OF AN INCH. A MOIST SOUTHERLY FLOW WILL CONTINUE ACROSS THE AREA TUESDAY...BRINGING MILD TEMPERATURES AND A CONTINUED CHANCE FOR SOME LIGHT SHOWERS. ANOTHER FRONT WILL SWEEP ACROSS THE STATE WEDNESDAY INTO THURSDAY...RESULTING IN A FAIRLY HEALTHY RAIN EVENT. 18DEC 12Z GEFS/EC BLEND CONTINUES TO INDICATE THE POTENTIAL FOR OVER ONE INCH OF RAIN IN SOME LOCATIONS OF THE STATE. ITS STILL MUCH TOO EARLY TO PIN DOWN ANY TYPE OF MESOSCALE FOCUS THAT WOULD LEAD TO HEAVIER RAIN BANDS. AT THIS POINT...CHRISTMAS EVE LOOKS TO BE THE WARMEST DAY NEXT WEEK WITH TEMPERATURES NUDGING INTO THE 60S IN THE SOUTHEAST. HOWEVER...A LOT DEPENDS ON THE TIMING OF THE FRONTAL PASSAGE AND ENSEMBLE SOLUTIONS STILL INDICATE A GOOD DEAL OF TEMPERATURE SPREAD. && .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... UPDATE THE TAFS MOST SITES ARE NOW SHOWING THE SURGE OF THE SECONDARY COLD PUSH WITH SOME GUSTY WINDS OVER THE REGION AND SPREADING EASTWARD. WINDS ACTUALLY SHOULD PEAK SATURDAY. MOST AREAS TO THE EAST ARE VFR WITH MORE MVFR TO THE WEST AND NORTHWEST. WINDS AND LOW CLOUDS WILL BE THE ISSUE FOR THE REST OF TODAY. SIGNIFICANT SNOW SHOWERS STILL HAVE NOT DEVELOPED. THIS WILL CHANGE IN THE 5-8 PM TIME FRAME IN THE NORTHWEST WHERE LAKE EFFECT SNOW WILL LOWER CIGS/VSBY AND SOME AREAS OF THE LAURELS. THE BEST SNOW WILL BE IN THE NORTHERN AREAS OF WARREN COUNTY OVERNIGHT AND INTO SATURDAY...AFFECTING KBFD. PUT SOME MENTION SNOW AT KJST TOO. MOST OTHER AREAS SHOULD BE QUITE GOOD OVERNIGHT AND SATURDAY...EXCEPT FOR GUSTY WINDS ESPECIALLY SATURDAY. SNOW TAPERS OFF IN NW SATURDAY EVENING/OVERNIGHT. AND THINGS IMPROVE...SUNDAY BIG BUBBLE NO TROUBLE AND VFR SHOULD DOMINATE. OUTLOOK... MON...PM SHRA/LOW CIGS POSS NW. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ005. LAKE EFFECT SNOW WARNING FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ004. && $$ SYNOPSIS...GRUMM NEAR TERM...GRUMM SHORT TERM...GRUMM LONG TERM...HAGNER AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
156 PM EST FRI DEC 18 2015 .SYNOPSIS... A DEEP BUT FLEETING 500MB TROUGH IS MOVING THROUGH THE REGION BRINGING US A TOUCH OF WINTER. THIS WILL INCLUDE A LAKE EFFECT SNOW EVENT IN NORTHWESTERN PENNSYLVANIA AND SOUTHWESTERN NEW YORK FRIDAY NIGHT INTO SATURDAY. A 500MB RIDGE WILL MOVE OVER THE REGION SUNDAY TO MONDAY AND MOVE OVER THE WESTERN ATLANTIC. A REBOUND WARM-UP IS FORECAST FOR SUNDAY-WEDNESDAY. BUT MOIST FLOW ABOUT THE MASSIVE RIDGE COULD BRING RAIN INTO THE REGION BY CHRISTMAS EVE. ABOVE NORMAL TEMPERATURES ARE EXPECTED FOR MOST OF THE COMING WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... COLD AIR CONTINUES TO MOVE ACROSS THE REGION AND THE WINDS HAVE BECOME A BIT GUSTY. THE CLOUDS WITH THE SECOND SURGE OF COLD AIR HAVE PUSHED INTO THE LOWER SUSQUEHANNA VALLEY. THE DAY WILL END CLOUDY TO MOSTLY CLOUDY. THE 0000 UTC 3KM NCAR ENSEMBLE SUGGESTED SNOW SHOWERS WOULD MOVE INTO WESTERN PENNSYLVANIA LATER THIS EVENING. THE NEW 16Z HRRR IS NOW SHOWING MEASURABLE SNOW AFTER 8 PM TONIGHT WHICH IS THE NEXT PERIOD. SOME MINOR POCKETS OF ISOLATED SNOW SHOWERS ARE IMPLIED IN THE HRRR IN THE LAURELS. MOSTLY CLOUDY AND BREEZY WILL BE THE MAIN WEATHER TODAY...SEASONABLY COLD FOR A NORMAL DECEMBER COLD FOR THE WARM DECEMBER OF 2015. SOME SNOW FLURRIES POSSIBLE IN THE NORTHERN AND WESTERN MOUNTAINS. BRIEF AND INTERMITTENT SNOW SHOWERS ARE POSSIBLE IN THE MOUNTAINS THIS AFTERNOON WHICH COULD COAT THE GROUND LATER THIS AFTERNOON AND EVENING. && .SHORT TERM /8 PM THIS EVENING THROUGH SATURDAY NIGHT/... *SIGNIFICANT LAKE EFFECT SNOW ACROSS THE NORTHWEST PA SNOWBELT FRIDAY NIGHT AND SATURDAY* THE 3KM HRRR NOW CAPTURES THE ONSET OF THE SNOW EVENT. INITIALLY IT KEEPS THE MAIN BAND NORTH OF THE PA/NY BORDER. IT DOES SHOW SOME MEASURABLE SNOW BY 10 PM THROUGH 2AM. A FEW INCHES. THE HRRR HAS AN INTENSE BAND OF HEAVY SNOW AT THIS TIME IN NY STATE...THIS BAND HAS 0.50 TO 0.70 INCHES OF QPF...THAT IS A LOT OF LES POTENTIAL. HOPEFULLY IT ALL STAYS IN NY. BASED ON THE HRRR...PREVIOUS NCAR EFS KEPT OUR SNOW IN THE 5-8 RANGE IN EXTREME NORTHERN WARREN COUNTY AND LOWER TO SOUTH AND WEST. ALSO SHOWED SOME SNOW IN THE LAURELS. WE WILL HAVE TO MONITOR THE HRRR FOR THE BIGGER BAND SHOULD IT TREND SOUTH. MOST OTHER AREAS COULD SEE SOME SNOW FLURRIES OVERNIGHT AND EARLY SATURDAY. IT SHOULD BECOME QUITE BREEZY SATURDAY IN THE COLD AIR. SOME GUIDANCE SHOWS CLOSE TO ADVISORY CATEGORY GUSTS IN THE SOUTHWEST MOUNTAINS SATURDAY AFTERNOON. PREVIOUS INFORMATION ON NCAR ENSEMBLE FORECAST... THE NCAR 3KM ENSEMBLE SHOWS THAT THE FIRST INCH OF SNOW AT THE 90 PERCENT CONFIDENCE LEVEL FALLS IN NORTHERN WARREN COUNTY BY ABOUT 9 PM. THE 3 INCH VALUES ARE REACHED BY ABOUT 8 AM SATURDAY. THE 6 INCH PROBABILITY AT 80 PERCENT OUR GREATER MOVES IN AROUND 10 AM AND PEAKING NEAR 100 PERCENT BY 3-4 PM. BEST CHANCE ACROSS NORTHERN AREAS OF WARREN COUNTY. THERE IS A 10 PERCENT CHANCE OF 1 FOOT OF SNOW IN A SLIVER OF NORTHWESTERN WARREN COUNTY. VERY LOW CHANCE OF A FOOT IN THE 3KM MODELS. && .LONG TERM /SUNDAY THROUGH THURSDAY/... A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT WILL DRIFT EAST ACROSS THE COMMONWEALTH ON SUNDAY...ACCOMPANIED BY A SLIGHT MODERATION IN TEMPERATURES AND LIGHTER WINDS. TEMPERATURES WILL REBOUND BY ANOTHER 5 TO 8 DEG F ON MONDAY AS AN UPPER TROUGH WEAKENS/SHEARS OUT TO THE NE ACROSS THE UPPER GLAKES. THE ASSOCIATED SFC LOW WILL PUSH A TROUGH OF LOW PRESSURE ACROSS THE STATE LATE MONDAY INTO TUESDAY...WHICH WILL HELP TO FOCUS SCATTERED SHOWERS. RAINFALL SHOULD BE LIMITED TO SVRL HUNDREDTHS OF AN INCH IN MOST PLACES...THOUGH THE FAR NW ZONES COULD SEE 1-2 TENTHS OF AN INCH. TEMPS /AND DEWPOINTS/ WILL LIKELY PEAK IN THE 50S ON WEDNESDAY BEFORE CLOUDS THICKEN UP FROM THE SOUTHWEST...AND USHER IN A FAIRLY HEALTHY RAIN EVENT WEDNESDAY INTO WEDNESDAY NIGHT. 18DEC 00Z GEFS/EC BLEND INDICATES THE POTENTIAL FOR OVER ONE INCH OF RAIN IN SOME LOCATIONS OF THE STATE. ITS STILL MUCH TOO EARLY TO PIN DOWN ANY TYPE OF MESOSCALE FOCUS THAT WOULD LEAD TO HEAVIER RAIN BANDS. LONGER RANGE POINTING TOWARD A COLD FRONT AROUND CHRISTMAS EVE/CHRISTMAS DAY...WITH SOME COOLER AIR WORKING IN - ESP NORTHERN AREAS. NO BIG COLD AIR OUTBREAK ON THE HORIZON THOUGH. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... UPDATE THE TAFS MOST SITES ARE NOW SHOWING THE SURGE OF THE SECONDARY COLD PUSH WITH SOME GUSTY WINDS OVER THE REGION AND SPREADING EASTWARD. WINDS ACTUALLY SHOULD PEAK SATURDAY. MOST AREAS TO THE EAST ARE VFR WITH MORE MVFR TO THE WEST AND NORTHWEST. WINDS AND LOW CLOUDS WILL BE THE ISSUE FOR THE REST OF TODAY. SIGNIFICANT SNOW SHOWERS STILL HAVE NOT DEVELOPED. THIS WILL CHANGE IN THE 5-8 PM TIME FRAME IN THE NORTHWEST WHERE LAKE EFFECT SNOW WILL LOWER CIGS/VSBY AND SOME AREAS OF THE LAURELS. THE BEST SNOW WILL BE IN THE NORTHERN AREAS OF WARREN COUNTY OVERNIGHT AND INTO SATURDAY...AFFECTING KBFD. PUT SOME MENTION SNOW AT KJST TOO. MOST OTHER AREAS SHOULD BE QUITE GOOD OVERNIGHT AND SATURDAY...EXCEPT FOR GUSTY WINDS ESPECIALLY SATURDAY. SNOW TAPERS OFF IN NW SATURDAY EVENING/OVERNIGHT. AND THINGS IMPROVE...SUNDAY BIG BUBBLE NO TROUBLE AND VFR SHOULD DOMINATE. OUTLOOK... MON...PM SHRA/LOW CIGS POSS NW. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ005. LAKE EFFECT SNOW WARNING FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ004. && $$ SYNOPSIS...GRUMM NEAR TERM...GRUMM SHORT TERM...GRUMM LONG TERM...LAMBERT/RXR AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
147 PM EST FRI DEC 18 2015 .SYNOPSIS... A SHORT-LIVED COLD SNAP WILL OCCUR OVER THE REGION TODAY AND SATURDAY WITH BANDS OF LAKE EFFECT SNOW IMPACTING AREAS DOWNWIND OF LAKE ERIE AND ALSO ACROSS THE LAUREL HIGHLANDS OF SOUTHWESTERN PENNSYLVANIA. ABOVE NORMAL TEMPERATURES MAKE A RETURN FOR SUNDAY AND CONTINUE THROUGH CHRISTMAS. PRIOR TO THE HOLIDAY...ANOTHER PERIOD OF RAIN APPEARS LIKELY HEADING INTO THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... COLD AIR CONTINUES TO MOVE ACROSS THE REGION AND THE WINDS HAVE BECOME A BIT GUSTY. THE CLOUDS WITH THE SECOND SURGE OF COLD AIR HAVE PUSHED INTO THE LOWER SUSQUEHANNA VALLEY. THE DAY WILL END CLOUDY TO MOSTLY CLOUDY. THE 0000 UTC 3KM NCAR ENSEMBLE SUGGESTED SNOW SHOWERS WOULD MOVE INTO WESTERN PENNSYLVANIA LATER THIS EVENING. THE NEW 16Z HRRR IS NOW SHOWING MEASURABLE SNOW AFTER 8 PM TONIGHT WHICH IS THE NEXT PERIOD. SOME MINOR POCKETS OF ISOLATED SNOW SHOWERS ARE IMPLIED IN THE HRRR IN THE LAURELS. MOSTLY CLOUDY AND BREEZY WILL BE THE MAIN WEATHER TODAY...SEASONABLY COLD FOR A NORMAL DECEMBER COLD FOR THE WARM DECEMBER OF 2015. SOME SNOW FLURRIES POSSIBLE IN THE NORTHERN AND WESTERN MOUNTAINS. BRIEF AND INTERMITTENT SNOW SHOWERS ARE POSSIBLE IN THE MOUNTAINS THIS AFTERNOON WHICH COULD COAT THE GROUND LATER THIS AFTERNOON AND EVENING. && .SHORT TERM /8 PM THIS EVENING THROUGH SATURDAY NIGHT/... *SIGNIFICANT LAKE EFFECT SNOW ACROSS THE NORTHWEST PA SNOWBELT FRIDAY NIGHT AND SATURDAY* THE 3KM HRRR NOW CAPTURES THE ONSET OF THE SNOW EVENT. INITIALLY IT KEEPS THE MAIN BAND NORTH OF THE PA/NY BORDER. IT DOES SHOW SOME MEASURABLE SNOW BY 10 PM THROUGH 2AM. A FEW INCHES. THE HRRR HAS AN INTENSE BAND OF HEAVY SNOW AT THIS TIME IN NY STATE...THIS BAND HAS 0.50 TO 0.70 INCHES OF QPF...THAT IS A LOT OF LES POTENTIAL. HOPEFULLY IT ALL STAYS IN NY. BASED ON THE HRRR...PREVIOUS NCAR EFS KEPT OUR SNOW IN THE 5-8 RANGE IN EXTREME NORTHERN WARREN COUNTY AND LOWER TO SOUTH AND WEST. ALSO SHOWED SOME SNOW IN THE LAURELS. WE WILL HAVE TO MONITOR THE HRRR FOR THE BIGGER BAND SHOULD IT TREND SOUTH. MOST OTHER AREAS COULD SEE SOME SNOW FLURRIES OVERNIGHT AND EARLY SATURDAY. IT SHOULD BECOME QUITE BREEZY SATURDAY IN THE COLD AIR. SOME GUIDANCE SHOWS CLOSE TO ADVISORY CATEGORY GUSTS IN THE SOUTHWEST MOUNTAINS SATURDAY AFTERNOON. PREVIOUS INFORMATION ON NCAR ENSEMBLE FORECAST... THE NCAR 3KM ENSEMBLE SHOWS THAT THE FIRST INCH OF SNOW AT THE 90 PERCENT CONFIDENCE LEVEL FALLS IN NORTHERN WARREN COUNTY BY ABOUT 9 PM. THE 3 INCH VALUES ARE REACHED BY ABOUT 8 AM SATURDAY. THE 6 INCH PROBABILITY AT 80 PERCENT OUR GREATER MOVES IN AROUND 10 AM AND PEAKING NEAR 100 PERCENT BY 3-4 PM. BEST CHANCE ACROSS NORTHERN AREAS OF WARREN COUNTY. THERE IS A 10 PERCENT CHANCE OF 1 FOOT OF SNOW IN A SLIVER OF NORTHWESTERN WARREN COUNTY. VERY LOW CHANCE OF A FOOT IN THE 3KM MODELS. && .LONG TERM /SUNDAY THROUGH THURSDAY/... A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT WILL DRIFT EAST ACROSS THE COMMONWEALTH ON SUNDAY...ACCOMPANIED BY A SLIGHT MODERATION IN TEMPERATURES AND LIGHTER WINDS. TEMPERATURES WILL REBOUND BY ANOTHER 5 TO 8 DEG F ON MONDAY AS AN UPPER TROUGH WEAKENS/SHEARS OUT TO THE NE ACROSS THE UPPER GLAKES. THE ASSOCIATED SFC LOW WILL PUSH A TROUGH OF LOW PRESSURE ACROSS THE STATE LATE MONDAY INTO TUESDAY...WHICH WILL HELP TO FOCUS SCATTERED SHOWERS. RAINFALL SHOULD BE LIMITED TO SVRL HUNDREDTHS OF AN INCH IN MOST PLACES...THOUGH THE FAR NW ZONES COULD SEE 1-2 TENTHS OF AN INCH. TEMPS /AND DEWPOINTS/ WILL LIKELY PEAK IN THE 50S ON WEDNESDAY BEFORE CLOUDS THICKEN UP FROM THE SOUTHWEST...AND USHER IN A FAIRLY HEALTHY RAIN EVENT WEDNESDAY INTO WEDNESDAY NIGHT. 18DEC 00Z GEFS/EC BLEND INDICATES THE POTENTIAL FOR OVER ONE INCH OF RAIN IN SOME LOCATIONS OF THE STATE. ITS STILL MUCH TOO EARLY TO PIN DOWN ANY TYPE OF MESOSCALE FOCUS THAT WOULD LEAD TO HEAVIER RAIN BANDS. LONGER RANGE POINTING TOWARD A COLD FRONT AROUND CHRISTMAS EVE/CHRISTMAS DAY...WITH SOME COOLER AIR WORKING IN - ESP NORTHERN AREAS. NO BIG COLD AIR OUTBREAK ON THE HORIZON THOUGH. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... UPDATE THE TAFS MOST SITES ARE NOW SHOWING THE SURGE OF THE SECONDARY COLD PUSH WITH SOME GUSTY WINDS OVER THE REGION AND SPREADING EASTWARD. WINDS ACTUALLY SHOULD PEAK SATURDAY. MOST AREAS TO THE EAST ARE VFR WITH MORE MVFR TO THE WEST AND NORTHWEST. WINDS AND LOW CLOUDS WILL BE THE ISSUE FOR THE REST OF TODAY. SIGNIFICANT SNOW SHOWERS STILL HAVE NOT DEVELOPED. THIS WILL CHANGE IN THE 5-8 PM TIME FRAME IN THE NORTHWEST WHERE LAKE EFFECT SNOW WILL LOWER CIGS/VSBY AND SOME AREAS OF THE LAURELS. THE BEST SNOW WILL BE IN THE NORTHERN AREAS OF WARREN COUNTY OVERNIGHT AND INTO SATURDAY...AFFECTING KBFD. PUT SOME MENTION SNOW AT KJST TOO. MOST OTHER AREAS SHOULD BE QUITE GOOD OVERNIGHT AND SATURDAY...EXCEPT FOR GUSTY WINDS ESPECIALLY SATURDAY. SNOW TAPERS OFF IN NW SATURDAY EVENING/OVERNIGHT. AND THINGS IMPROVE...SUNDAY BIG BUBBLE NO TROUBLE AND VFR SHOULD DOMINATE. OUTLOOK... MON...PM SHRA/LOW CIGS POSS NW. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ005. LAKE EFFECT SNOW WARNING FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ004. && $$ SYNOPSIS...LAMBERT/STEINBUGL NEAR TERM...GRUMM SHORT TERM...GRUMM LONG TERM...LAMBERT/RXR AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1240 PM EST FRI DEC 18 2015 .SYNOPSIS... A SHORT-LIVED COLD SNAP WILL OCCUR OVER THE REGION TODAY AND SATURDAY WITH BANDS OF LAKE EFFECT SNOW IMPACTING AREAS DOWNWIND OF LAKE ERIE AND ALSO ACROSS THE LAUREL HIGHLANDS OF SOUTHWESTERN PENNSYLVANIA. ABOVE NORMAL TEMPERATURES MAKE A RETURN FOR SUNDAY AND CONTINUE THROUGH CHRISTMAS. PRIOR TO THE HOLIDAY...ANOTHER PERIOD OF RAIN APPEARS LIKELY HEADING INTO THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... COLD AIR STILL MOVING OVER THE REGION BEHIND THE COLD FRONT TODAY. THIS WILL BE ONE OF THE MORE WINTRY FEELING DAYS IN A LONG WHILE. MODELS ALL SHOW LOTS OF CLOUDS IN THE MOUNTAINS OF CENTRAL AND WESTERN PENNSYLVANIA TODAY WITH PARTLY CLOUDY SKIES EAST OF MOUNTAINS. HRRR AND THE 3KM NCAR ENSEMBLE SUGGEST THE FIRST BANDS OF SNOW AND SNOW SHOWERS MOVE INTO WESTERN PENNSYLVANIA LATER THIS EVENING. DO NOT EXPECT MORE THAN SNOW FLURRIES BEFORE A 6 PM. LIGHT SNOW COULD AFFECT THE NORTHWESTERNMOST AREAS OF WARREN COUNTY AND THE LAURELS A FEW HOURS EITHER SIDE OF 8 PM. THE HRRR HOLDS OFF UNTIL 11 PM THE NCAR ENSEMBLE IMPLIES A 20 PERCENT CHANCE OF 1 INCH OF SNOW IN EXTREME NORTHERN WARREN COUNTY AFTER ABOUT 6 PM. && .SHORT TERM /8 PM THIS EVENING THROUGH SATURDAY NIGHT/... *SIGNIFICANT LAKE EFFECT SNOW ACROSS THE NORTHWEST PA SNOWBELT FRIDAY NIGHT AND SATURDAY* THE NCAR 3KM ENSEMBLE SHOWS THAT THE FIRST INCH OF SNOW AT THE 90 PERCENT CONFIDENCE LEVEL FALLS IN NORTHERN WARREN COUNTY BY ABOUT 9 PM. THE 3 INCH VALUES ARE REACHED BY ABOUT 8 AM SATURDAY. THE 6 INCH PROBABILITY AT 80 PERCENT OUR GREATER MOVES IN AROUND 10 AM AND PEAKING NEAR 100 PERCENT BY 3-4 PM. BEST CHANCE ACROSS NORTHERN AREAS OF WARREN COUNTY. THERE IS A 10 PERCENT CHANCE OF 1 FOOT OF SNOW IN A SLIVER OF NORTHWESTERN WARREN COUNTY. VERY LOW CHANCE OF A FOOT IN THE 3KM MODELS. THE SREF AND NAM ALL SHOW A GOOD POTENTIAL FOR 3-6 INCHES OF SNOW AS WELL. THE HEAVIER SNOW IS BEYOND THE LIMBS OF THE HRRR WHICH ONLY GOES TO ABOUT 11 PM AT THIS TIME. SO HIGH CONFIDENCE OF 5-8 INCHES IN NORTHERN WARREN AND 2-5 OTHER PARTS OF WARREN AND MCKEAN COUNTY OVERNIGHT AND DURING THE DAY SATURDAY. THESE NUMBERS ARE WELL WITHIN WPC WINTER SNOW GUIDANCE PROBABILITY RANGES. IT WILL BE MAINLY IN THE 20S IN THE SNOW AREAS WITH GUSTY WINDS. IN THE LAURELS THERE COULD BE 1-2 INCHES OF SNOW OVERNIGHT AND SATURDAY. THE REST OF THE REGION LOOKS PARTLY TO MOSTLY CLOUDY SATURDAY. IT WILL PROBABLY BE THE COLDEST DAY OF THE MONTH IN MANY LOCATIONS AND LIKELY THE COLDEST DAY UNTIL NEXT YEAR. THE WINDS WILL ADD TO THAT BRISK WINTRY FEELING. && .LONG TERM /SUNDAY THROUGH THURSDAY/... A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT WILL DRIFT EAST ACROSS THE COMMONWEALTH ON SUNDAY...ACCOMPANIED BY A SLIGHT MODERATION IN TEMPERATURES AND LIGHTER WINDS. TEMPERATURES WILL REBOUND BY ANOTHER 5 TO 8 DEG F ON MONDAY AS AN UPPER TROUGH WEAKENS/SHEARS OUT TO THE NE ACROSS THE UPPER GLAKES. THE ASSOCIATED SFC LOW WILL PUSH A TROUGH OF LOW PRESSURE ACROSS THE STATE LATE MONDAY INTO TUESDAY...WHICH WILL HELP TO FOCUS SCATTERED SHOWERS. RAINFALL SHOULD BE LIMITED TO SVRL HUNDREDTHS OF AN INCH IN MOST PLACES...THOUGH THE FAR NW ZONES COULD SEE 1-2 TENTHS OF AN INCH. TEMPS /AND DEWPOINTS/ WILL LIKELY PEAK IN THE 50S ON WEDNESDAY BEFORE CLOUDS THICKEN UP FROM THE SOUTHWEST...AND USHER IN A FAIRLY HEALTHY RAIN EVENT WEDNESDAY INTO WEDNESDAY NIGHT. 18DEC 00Z GEFS/EC BLEND INDICATES THE POTENTIAL FOR OVER ONE INCH OF RAIN IN SOME LOCATIONS OF THE STATE. ITS STILL MUCH TOO EARLY TO PIN DOWN ANY TYPE OF MESOSCALE FOCUS THAT WOULD LEAD TO HEAVIER RAIN BANDS. LONGER RANGE POINTING TOWARD A COLD FRONT AROUND CHRISTMAS EVE/CHRISTMAS DAY...WITH SOME COOLER AIR WORKING IN - ESP NORTHERN AREAS. NO BIG COLD AIR OUTBREAK ON THE HORIZON THOUGH. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... UPDATE THE TAFS MOST SITES ARE NOW SHOWING THE SURGE OF THE SECONDARY COLD PUSH WITH SOME GUSTY WINDS OVER THE REGION AND SPREADING EASTWARD. WINDS ACTUALLY SHOULD PEAK SATURDAY. MOST AREAS TO THE EAST ARE VFR WITH MORE MVFR TO THE WEST AND NORTHWEST. WINDS AND LOW CLOUDS WILL BE THE ISSUE FOR THE REST OF TODAY. SIGNIFICANT SNOW SHOWERS STILL HAVE NOT DEVELOPED. THIS WILL CHANGE IN THE 5-8 PM TIME FRAME IN THE NORTHWEST WHERE LAKE EFFECT SNOW WILL LOWER CIGS/VSBY AND SOME AREAS OF THE LAURELS. THE BEST SNOW WILL BE IN THE NORTHERN AREAS OF WARREN COUNTY OVERNIGHT AND INTO SATURDAY...AFFECTING KBFD. PUT SOME MENTION SNOW AT KJST TOO. MOST OTHER AREAS SHOULD BE QUITE GOOD OVERNIGHT AND SATURDAY...EXCEPT FOR GUSTY WINDS ESPECIALLY SATURDAY. SNOW TAPERS OFF IN NW SATURDAY EVENING/OVERNIGHT. AND THINGS IMPROVE...SUNDAY BIG BUBBLE NO TROUBLE AND VFR SHOULD DOMINATE. OUTLOOK... MON...PM SHRA/LOW CIGS POSS NW. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ005. LAKE EFFECT SNOW WARNING FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ004. && $$ SYNOPSIS...LAMBERT/STEINBUGL NEAR TERM...GRUMM SHORT TERM...GRUMM/STEINBUGL LONG TERM...LAMBERT/RXR AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1026 AM EST FRI DEC 18 2015 .SYNOPSIS... A SHORT-LIVED COLD SNAP WILL OCCUR OVER THE REGION TODAY AND SATURDAY WITH BANDS OF LAKE EFFECT SNOW IMPACTING AREAS DOWNWIND OF LAKE ERIE AND ALSO ACROSS THE LAUREL HIGHLANDS OF SOUTHWESTERN PENNSYLVANIA. ABOVE NORMAL TEMPERATURES MAKE A RETURN FOR SUNDAY AND CONTINUE THROUGH CHRISTMAS. PRIOR TO THE HOLIDAY...ANOTHER PERIOD OF RAIN APPEARS LIKELY HEADING INTO THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... COLD AIR STILL MOVING OVER THE REGION BEHIND THE COLD FRONT TODAY. THIS WILL BE ONE OF THE MORE WINTRY FEELING DAYS IN A LONG WHILE. MODELS ALL SHOW LOTS OF CLOUDS IN THE MOUNTAINS OF CENTRAL AND WESTERN PENNSYLVANIA TODAY WITH PARTLY CLOUDY SKIES EAST OF MOUNTAINS. HRRR AND THE 3KM NCAR ENSEMBLE SUGGEST THE FIRST BANDS OF SNOW AND SNOW SHOWERS MOVE INTO WESTERN PENNSYLVANIA LATER THIS EVENING. DO NOT EXPECT MORE THAN SNOW FLURRIES BEFORE A 6 PM. LIGHT SNOW COULD AFFECT THE NORTHWESTERNMOST AREAS OF WARREN COUNTY AND THE LAURELS A FEW HOURS EITHER SIDE OF 8 PM. THE HRRR HOLDS OFF UNTIL 11 PM THE NCAR ENSEMBLE IMPLIES A 20 PERCENT CHANCE OF 1 INCH OF SNOW IN EXTREME NORTHERN WARREN COUNTY AFTER ABOUT 6 PM. && .SHORT TERM /8 PM THIS EVENING THROUGH SATURDAY NIGHT/... *SIGNIFICANT LAKE EFFECT SNOW ACROSS THE NORTHWEST PA SNOWBELT FRIDAY NIGHT AND SATURDAY* THE NCAR 3KM ENSEMBLE SHOWS THAT THE FIRST INCH OF SNOW AT THE 90 PERCENT CONFIDENCE LEVEL FALLS IN NORTHERN WARREN COUNTY BY ABOUT 9 PM. THE 3 INCH VALUES ARE REACHED BY ABOUT 8 AM SATURDAY. THE 6 INCH PROBABILITY AT 80 PERCENT OUR GREATER MOVES IN AROUND 10 AM AND PEAKING NEAR 100 PERCENT BY 3-4 PM. BEST CHANCE ACROSS NORTHERN AREAS OF WARREN COUNTY. THERE IS A 10 PERCENT CHANCE OF 1 FOOT OF SNOW IN A SLIVER OF NORTHWESTERN WARREN COUNTY. VERY LOW CHANCE OF A FOOT IN THE 3KM MODELS. THE SREF AND NAM ALL SHOW A GOOD POTENTIAL FOR 3-6 INCHES OF SNOW AS WELL. THE HEAVIER SNOW IS BEYOND THE LIMBS OF THE HRRR WHICH ONLY GOES TO ABOUT 11 PM AT THIS TIME. SO HIGH CONFIDENCE OF 5-8 INCHES IN NORTHERN WARREN AND 2-5 OTHER PARTS OF WARREN AND MCKEAN COUNTY OVERNIGHT AND DURING THE DAY SATURDAY. THESE NUMBERS ARE WELL WITHIN WPC WINTER SNOW GUIDANCE PROBABILITY RANGES. IT WILL BE MAINLY IN THE 20S IN THE SNOW AREAS WITH GUSTY WINDS. IN THE LAURELS THERE COULD BE 1-2 INCHES OF SNOW OVERNIGHT AND SATURDAY. THE REST OF THE REGION LOOKS PARTLY TO MOSTLY CLOUDY SATURDAY. IT WILL PROBABLY BE THE COLDEST DAY OF THE MONTH IN MANY LOCATIONS AND LIKELY THE COLDEST DAY UNTIL NEXT YEAR. THE WINDS WILL ADD TO THAT BRISK WINTRY FEELING. && .LONG TERM /SUNDAY THROUGH THURSDAY/... A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT WILL DRIFT EAST ACROSS THE COMMONWEALTH ON SUNDAY...ACCOMPANIED BY A SLIGHT MODERATION IN TEMPERATURES AND LIGHTER WINDS. TEMPERATURES WILL REBOUND BY ANOTHER 5 TO 8 DEG F ON MONDAY AS AN UPPER TROUGH WEAKENS/SHEARS OUT TO THE NE ACROSS THE UPPER GLAKES. THE ASSOCIATED SFC LOW WILL PUSH A TROUGH OF LOW PRESSURE ACROSS THE STATE LATE MONDAY INTO TUESDAY...WHICH WILL HELP TO FOCUS SCATTERED SHOWERS. RAINFALL SHOULD BE LIMITED TO SVRL HUNDREDTHS OF AN INCH IN MOST PLACES...THOUGH THE FAR NW ZONES COULD SEE 1-2 TENTHS OF AN INCH. TEMPS /AND DEWPOINTS/ WILL LIKELY PEAK IN THE 50S ON WEDNESDAY BEFORE CLOUDS THICKEN UP FROM THE SOUTHWEST...AND USHER IN A FAIRLY HEALTHY RAIN EVENT WEDNESDAY INTO WEDNESDAY NIGHT. 18DEC 00Z GEFS/EC BLEND INDICATES THE POTENTIAL FOR OVER ONE INCH OF RAIN IN SOME LOCATIONS OF THE STATE. ITS STILL MUCH TOO EARLY TO PIN DOWN ANY TYPE OF MESOSCALE FOCUS THAT WOULD LEAD TO HEAVIER RAIN BANDS. LONGER RANGE POINTING TOWARD A COLD FRONT AROUND CHRISTMAS EVE/CHRISTMAS DAY...WITH SOME COOLER AIR WORKING IN - ESP NORTHERN AREAS. NO BIG COLD AIR OUTBREAK ON THE HORIZON THOUGH. && .AVIATION /15Z FRIDAY THROUGH TUESDAY/... MINOR UPDATES TO TAFS AT 15Z FOR WINDS AND SKIES. NOTHING SIGNIFICANT. MAINLY VFR OVER MOST OF THE EAST WITH CEILINGS MAINLY ABOVE 4KFT. SOME VFR AND AREAS OF MVFR DUE TO CIGS BELOW 3KFT WILL IMPACT THE CENTRAL AREAS. THE LOW CLOUDS TRAPPED IN THE MOUNTAINS HAVE BASES MAINLY IN THE 2-4KFT RANGE. SOME GUSTY WINDS TOO...GUSTY WINDS WILL BE MORE WIDESPREAD IN THE AFTERNOON. IN THE WEST AND HIGHER TERRAIN MAINLY MVFR. DO NOT EXPECT ANY SIGNIFICANT IMPROVEMENT TODAY. THIS EVENING SNOW WILL FURTHER REDUCE THE CIGS AND LOWER THE VISIBILITY. OVERNIGHT INTO SATURDAY AROUND KBFD THERE WILL BE IFR CONDITIONS IN SNOW AND SNOW SHOWERS. A SIGNIFICANT LAKE EFFECT SNOW IS EXPECTED MAINLY FRIDAY NIGHT INTO SATURDAY AFTERNOON. KJST WILL BE AFFECTED BY SNOW TOO THOUGH MAINLY MVFR PERHAPS TIMES OF IFR...SNOW SHOULD BE MUCH LIGHTER IN THE SOUTHWEST MOUNTAINS. SUNDAY BIG BUBBLE NO TROUBLE AND VFR SHOULD DOMINATE. OUTLOOK... MON...PM SHRA/LOW CIGS POSS NW. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ005. LAKE EFFECT SNOW WARNING FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ004. && $$ SYNOPSIS...LAMBERT/STEINBUGL NEAR TERM...GRUMM SHORT TERM...GRUMM/STEINBUGL LONG TERM...LAMBERT/RXR AVIATION...GRUMM/STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1012 AM EST FRI DEC 18 2015 .SYNOPSIS... A SHORT-LIVED COLD SNAP WILL OCCUR OVER THE REGION TODAY AND SATURDAY WITH BANDS OF LAKE EFFECT SNOW IMPACTING AREAS DOWNWIND OF LAKE ERIE AND ALSO ACROSS THE LAUREL HIGHLANDS OF SOUTHWESTERN PENNSYLVANIA. ABOVE NORMAL TEMPERATURES MAKE A RETURN FOR SUNDAY AND CONTINUE THROUGH CHRISTMAS. PRIOR TO THE HOLIDAY...ANOTHER PERIOD OF RAIN APPEARS LIKELY HEADING INTO THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... COLD AIR STILL MOVING OVER THE REGION BEHIND THE COLD FRONT TODAY. THIS WILL BE ONE OF THE MORE WINTRY FEELING DAYS IN A LONG WHILE. MODELS ALL SHOW LOTS OF CLOUDS IN THE MOUNTAINS OF CENTRAL AND WESTERN PENNSYLVANIA TODAY WITH PARTLY CLOUDY SKIES EAST OF MOUNTAINS. HRRR AND THE 3KM NCAR ENSEMBLE SUGGEST THE FIRST BANDS OF SNOW AND SNOW SHOWERS MOVE INTO WESTERN PENNSYLVANIA LATER THIS EVENING. DO NOT EXPECT MORE THAN SNOW FLURRIES BEFORE A 6 PM. LIGHT SNOW COULD AFFECT THE NORTHWESTERNMOST AREAS OF WARREN COUNTY AND THE LAURELS A FEW HOURS EITHER SIDE OF 8 PM. THE HRRR HOLDS OFF UNTIL 11 PM THE NCAR ENSEMBLE IMPLIES A 20 PERCENT CHANCE OF 1 INCH OF SNOW IN EXTREME NORTHERN WARREN COUNTY AFTER ABOUT 6 PM. && .SHORT TERM /8 PM THIS EVENING THROUGH SATURDAY NIGHT/... *SIGNIFICANT LAKE EFFECT SNOW ACROSS THE NORTHWEST PA SNOWBELT FRIDAY NIGHT AND SATURDAY* THE NCAR 3KM ENSEMBLE SHOWS THAT THE FIRST INCH OF SNOW AT THE 90 PERCENT CONFIDENCE LEVEL FALLS IN NORTHERN WARREN COUNTY BY ABOUT 9 PM. THE 3 INCH VALUES ARE REACHED BY ABOUT 8 AM SATURDAY. THE 6 INCH PROBABILITY AT 80 PERCENT OUR GREATER MOVES IN AROUND 10 AM AND PEAKING NEAR 100 PERCENT BY 3-4 PM. BEST CHANCE ACROSS NORTHERN AREAS OF WARREN COUNTY. THERE IS A 10 PERCENT CHANCE OF 1 FOOT OF SNOW IN A SLIVER OF NORTHWESTERN WARREN COUNTY. VERY LOW CHANCE OF A FOOT IN THE 3KM MODELS. THE SREF AND NAM ALL SHOW A GOOD POTENTIAL FOR 3-6 INCHES OF SNOW AS WELL. THE HEAVIER SNOW IS BEYOND THE LIMBS OF THE HRRR WHICH ONLY GOES TO ABOUT 11 PM AT THIS TIME. SO HIGH CONFIDENCE OF 5-8 INCHES IN NORTHERN WARREN AND 2-5 OTHER PARTS OF WARREN AND MCKEAN COUNTY OVERNIGHT AND DURING THE DAY SATURDAY. THESE NUMBERS ARE WELL WITHIN WPC WINTER SNOW GUIDANCE PROBABILITY RANGES. IT WILL BE MAINLY IN THE 20S IN THE SNOW AREAS WITH GUSTY WINDS. IN THE LAURELS THERE COULD BE 1-2 INCHES OF SNOW OVERNIGHT AND SATURDAY. THE REST OF THE REGION LOOKS PARTLY TO MOSTLY CLOUDY SATURDAY. IT WILL PROBABLY BE THE COLDEST DAY OF THE MONTH IN MANY LOCATIONS AND LIKELY THE COLDEST DAY UNTIL NEXT YEAR. THE WINDS WILL ADD TO THAT BRISK WINTRY FEELING. && .LONG TERM /SUNDAY THROUGH THURSDAY/... A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT WILL DRIFT EAST ACROSS THE COMMONWEALTH ON SUNDAY...ACCOMPANIED BY A SLIGHT MODERATION IN TEMPERATURES AND LIGHTER WINDS. TEMPERATURES WILL REBOUND BY ANOTHER 5 TO 8 DEG F ON MONDAY AS AN UPPER TROUGH WEAKENS/SHEARS OUT TO THE NE ACROSS THE UPPER GLAKES. THE ASSOCIATED SFC LOW WILL PUSH A TROUGH OF LOW PRESSURE ACROSS THE STATE LATE MONDAY INTO TUESDAY...WHICH WILL HELP TO FOCUS SCATTERED SHOWERS. RAINFALL SHOULD BE LIMITED TO SVRL HUNDREDTHS OF AN INCH IN MOST PLACES...THOUGH THE FAR NW ZONES COULD SEE 1-2 TENTHS OF AN INCH. TEMPS /AND DEWPOINTS/ WILL LIKELY PEAK IN THE 50S ON WEDNESDAY BEFORE CLOUDS THICKEN UP FROM THE SOUTHWEST...AND USHER IN A FAIRLY HEALTHY RAIN EVENT WEDNESDAY INTO WEDNESDAY NIGHT. 18DEC 00Z GEFS/EC BLEND INDICATES THE POTENTIAL FOR OVER ONE INCH OF RAIN IN SOME LOCATIONS OF THE STATE. ITS STILL MUCH TOO EARLY TO PIN DOWN ANY TYPE OF MESOSCALE FOCUS THAT WOULD LEAD TO HEAVIER RAIN BANDS. LONGER RANGE POINTING TOWARD A COLD FRONT AROUND CHRISTMAS EVE/CHRISTMAS DAY...WITH SOME COOLER AIR WORKING IN - ESP NORTHERN AREAS. NO BIG COLD AIR OUTBREAK ON THE HORIZON THOUGH. && .AVIATION /15Z FRIDAY THROUGH TUESDAY/... MVFR CIGS WILL CONTINUE TO IMPACT THE WESTERN AND CENTRAL AIRSPACE WITH LITTLE TO NO IMPROVEMENT FCST BY THE AFTERNOON. THE EASTERN AIRFIELDS IPT/MDT AND LNS SHOULD AVOID CIG RESTRICTIONS BUT REMAIN LOW VFR. LAKE EFFECT AND OROGRAPHIC SNOWS WILL DEVELOP TONIGHT AND CONTINUE INTO SATURDAY WITH MAIN AVN IMPACTS TO BFD AND JST. GREATEST RISK OF IFR IS AT BFD LATE TONIGHT INTO SATURDAY. WEST- NORTHWEST WINDS (280-310) WILL BE A FACTOR ON SATURDAY WITH PEAK GUSTS IN THE 25-30KT RANGE. HIGH PRESSURE RETURNS VFR FOR SUNDAY. OUTLOOK... MON...PM SHRA/LOW CIGS POSS NW. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ005. LAKE EFFECT SNOW WARNING FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY FOR PAZ004. && $$ SYNOPSIS...LAMBERT/STEINBUGL NEAR TERM...GRUMM SHORT TERM...GRUMM/STEINBUGL LONG TERM...LAMBERT/RXR AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
ISSUED BY NATIONAL WEATHER SERVICE NEW ORLEANS LA 936 AM CST FRI DEC 18 2015 .DISCUSSION...UPDATED FOR LATEST MARINE DISCUSSION BELOW. && .MARINE... WILL LET THE SMALL CRAFT ADVISORY EXPIRE AND KEEP GRADIENT WIND AROUND 18 KNOTS FOR THE REST OF THIS MORNING. THIS IS CONSISTENT WITH SHORT RANGE RAP13 AND HRRR FORECAST MODELS. && .PREV DISCUSSION... /ISSUED 722 AM CST FRI DEC 18 2015/ DISCUSSION...UPDATED FOR LATEST MARINE DISCUSSION BELOW. MARINE...HIGH PRESSURE SURGING OVER THE AREA FROM THE NORTHWEST HAS TIGHTENED THE LOCAL PRESSURE GRADIENT AND RESULTED IN A BRIEF INCREASE IN WINDS. HOISTED A SMALL CRAFT ADVISORY UNTIL THE REGULAR MORNING UPDATE. NORTH NORTHEAST WINDS APPEAR TO HAVE PEAKED AND MAY SOON BE HEADED DOWN...SO WILL REEVALUATE FOR MORNING UPDATE. PREV DISCUSSION... /ISSUED 519 AM CST FRI DEC 18 2015/ DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. AVIATION...SATELLITE IMAGES AND SURFACE OBSERVATIONS INDICATE MOSTLY HIGH CLOUDS ACROSS THE CWA EARLY THIS MORNING. EXPECT VFR CONDITIONS TO PREVAIL TODAY INTO TONIGHT AS A 500MB RIDGE ACROSS THE WESTERN UNITED STATES CONTINUES TO PROVIDE SUBSIDENCE ACROSS THE RIO GRANDE VALLEY THIS AFTERNOON INTO THIS EVENING. PREV DISCUSSION... /ISSUED 336 AM CST FRI DEC 18 2015/ SHORT TERM /TODAY THROUGH SATURDAY/...500MB RIDGE ACROSS THE WESTERN UNITED STATES AND 500MB TROUGH ACROSS THE EASTERN U.S. WILL PROVIDE WEST TO NORTHWEST FLOW ALOFT ACROSS THE CWA TODAY. SUBSIDENCE WILL BEGIN TO DIMINISH TONIGHT INTO SATURDAY AS THE FLOW ALOFT BACKS TO THE SOUTHWEST ACROSS WEST TEXAS. AN ONSHORE FLOW WILL RETURN AT THE SURFACE TONIGHT INTO SATURDAY AND THIS WILL ALLOW ISOLATED SHOWERS TO DEVELOP OFFSHORE THE LOWER TEXAS COAST SAT AFTERNOON. LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...RIDGE WILL TRAVEL EAST AS THE NEXT SHORTWAVE ENTERS THE PACIFIC NW EARLY IN THE LONG TERM. SURFACE HIGH WILL DRIFT EAST INTO THE SE PLAINS ALLOWING FOR LOW AND MID LEVEL MOISTURE TO SURGE NORTH FROM THE GULF WATERS SAT NIGHT INTO SUN. THE TROUGH AXIS DEEPENS AND AS IT STRENGTHS SURFACE LOW OVER OK INTERACTS WITH HIGH TO THE EAST ALLOWING THE PG TO STRENGTHEN ALONG THE RGV. SE WINDS INCREASE AS GRADIENT STRENGTHENS WITH MODERATE TO BREEZE WINDS ALONG THE COAST AND LESS FURTHER INLAND SUNDAY. LOW LEVEL MOISTURE CONTENT POOLS OVER SOUTH CENTRAL TEXAS INCREASING THE CHANCES OF ISO SHOWERS LATE SUN INTO MONDAY WITH THE TAIL END OF THE TROUGH REMAINING ALMOST STATIONARY NORTH OF THE CWA. MORE FAVORABLE LOCATIONS TO SEE RAINFALL REMAIN ALONG AND EAST OF HWY 281. DEEP MOISTURE WITH STATIONARY FRONT EXTEND ACROSS THE WESTERN TO NORTHERN GULF WATERS WHICH WILL ENHANCE THE POTENTIAL FOR RAIN EVEN MORE SO MON INTO TUE. RAIN CONTINUES INTO TUESDAY FAVORING ONCE AGAIN THE INTERIOR AND COASTAL COUNTIES. AS THE NEXT SYSTEM DEEPENS A MORE SW FLOW DEVELOPS OVER THE DESERT SW WHICH STRENGTHENS THE CAP TUE. THIS WILL LIMIT THE POTENTIAL FOR RAIN FOR THE SOUTHWESTERN PORTION OF THE CWA. THE ELONGATED TROUGH WITH ITS AXIS STRETCH ACROSS THE WEST MOVES E LATE TUE INTO WED AS IT DEEPENS A FRONT MOVES ACROSS THE AREA WITH MUCH DRY AIR FILTERING INTO THE CWA. THIS WILL DIMINISH THE POTENTIAL FOR RAIN WEDNESDAY AND THURSDAY WITH A LIGHT TO N TO NE WIND. POSSIBLE MOISTURE CONTENT RETURNS INTO FRIDAY, CHRISTMAS DAY WHICH COULD ENHANCE A FEW ISOLATED SHOWERS ACROSS THE RGV IN THE AFTERNOON. MARINE...TODAY THROUGH SATURDAY...SEAS WERE NEAR 3 FEET WITH NORTH TO NORTHWEST WINDS NEAR 12 KNOTS AT BUOY020 EARLY THIS MORNING. MODERATE TO STRONG NORTH WINDS ARE EXPECTED TO DEVELOP ACROSS THE COASTAL WATERS THIS MORNING AS THE PRESSURE GRADIENT INCREASES ACROSS THE LOWER TEXAS COAST. WILL WORD SCEC FOR THE OFFSHORE WATERS TODAY AS A RESULT. WINDS AND SEAS WILL DIMINISH THIS AFTERNOON AFTER INCREASING THIS MORNING AS THE SURFACE RIDGE OVER EAST TEXAS MOVES EASTWARD ALLOWING WINDS TO VEER TO THE EAST TONIGHT AND THE PRESSURE GRADIENT TO RELAX ALONG THE LOWER TEXAS COAST. LIGHT EAST WINDS TONIGHT WILL VEER TO THE SOUTHEAST SATURDAY AND INCREASE SLIGHTLY AS HIGH PRESSURE SETTLES ACROSS THE SOUTHEAST UNITED STATES. SATURDAY NIGHT THROUGH FRIDAY...GRADIENT STRENGTHENS AS THE NEXT SYSTEM MOVES INTO THE CENTRAL PLAINS SUN. THIS WILL ALLOW FOR SCEC CONDITIONS WITH SEAS BUILDING CLOSE TO 5 TO 6 FEET THROUGH MONDAY. A WEAK WARM FRONT WITH ABUNDANT MOISTURE WILL ENHANCE ISO TO SCT SHOWERS MONDAY AND TUESDAY WITH A MODERATE SOUTHERLY FLOW. THIS WILL RESULT IN INCREASE OF SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY WHILE SEAS REMAIN 2 TO 4 FEET. INTO WEDNESDAY THE NEXT TROUGH TRAVELS EAST WITH THE ARRIVAL OF THE NEXT FRONT. DRY AIR MAKES ITS WAY INTO THE GULF WATERS WHILE RIDGE SHIFTS GRADUALLY EAST. THE GRADIENT REMAINS WEAK KEEPING A LIGHT WIND FLOW WITH ONLY CHANGE REMAINING THE DIRECTION AS IT VEERS SE BY THE NEXT WEEKEND. BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT ADVISORY UNTIL 9 AM CST THIS MORNING FOR GMZ150-155- 170-175. $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 99/99
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1148 PM EST THU DEC 17 2015 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION OVERNIGHT. HIGH PRESSURE WILL GRADUALLY WORK ITS WAY INTO THE AREA...BECOMING CENTERED OVER THE CENTRAL APPALACHIANS BY SUNDAY MORNING. A COLD FRONT...AND THEN POTENTIALLY A SERIES OF DISTURBANCES...WILL IMPACT OUR REGION FROM MONDAY AND ONWARD NEXT WEEK. && .NEAR TERM /THROUGH FRIDAY/... AS OF 950 PM EST THURSDAY... AT 9PM THE COLD FRONT WAS ALONG THE BLUE RIDGE WITH LOWER DEW POINTS AND TEMPERATURES IN THE UPPER 30S TO UPPER 40S WEST OF THE BOUNDARY. TO THE EAST WINDS WERE LIGHT AND VARIABLE. THE LAST WAVE OF LOW PRESSURE WILL MOVE ALONG THE FRONT TONIGHT WITH WINDS TURNING TO THE NORTHWEST AND INCREASING IN SPEEDS ONCE THE LOW MOVES EAST OF THE FORECAST AREA. HRRR AND LOCAL WRF GUIDANCE HAVE BEST CHANCE OF RAIN WITH THIS LOW IN THE SOUTHEAST COUNTY WARNING AREA BETWEEN 05Z/MIDNIGHT AND 11Z/6AM. ONLY MINOR CHANGES NEEDED TO OVERNIGHT LOWS. A STRONGER SURGE OF LOW LEVEL MOISTURE...AND THE ONSET OF EVEN STRONGER NORTHWEST FLOW WILL REACH WESTERN PARTS OF THE AREA LATE TONIGHT INTO EARLY FRIDAY MORNING. THIS BOOST WILL BRING AN INCREASE TO THE UPSLOPE PRECIPITATION IN THE WEST. WITH COLDER AIR ALOFT STILL ARRIVING AND LITTLE INCREASE IN TEMPERATURES FROM THE MORNING LOW TEMPERATURES...THE PREFERRED UPSLOPE AREAS OF SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA MAY SEE SOME AREAS THAT RECEIVE SNOWFALL UP TO AROUND ONE-HALF INCH. A CHALLENGE TO ACHIEVE MEASURABLE SNOW WILL BE HOW WARM THE GROUND HAS BEEN THIS DECEMBER...AND MINIMAL SNOWFALL RATES. OTHER PORTIONS OF THIS REGION WILL BE TOO WARM FOR SNOW AND EXPERIENCE SOME LIGHT RAIN SHOWERS. THE REMAINDER OF THE FORECAST AREA...ESPECIALLY REGIONS EAST OF THE CREST OF THE BLUE RIDGE...WILL NOT EXPERIENCE PRECIPITATION. RATHER...A TREND TOWARDS DECREASING CLOUD COVER IS EXPECTED THANKS TO A STRENGTHENING DOWNSLOPE FLOW. BY THE AFTERNOON...NORTHWEST 850 MB WINDS ARE PROGGED TO BE IN THE NEIGHBORHOOD OF 40 KTS. GUSTS IN THE 20 TO 25 MPH RANGE WILL BE COMMON ACROSS THE MOUNTAINS WITH THE HIGHEST PEAKS EXPERIENCING GUSTS CLOSER TO 30 TO 35 MPH. ACROSS THE PIEDMONT...WIND GUSTS WILL GENERALLY BE IN THE 15 TO 20 MPH RANGE BY THE AFTERNOON. HIGH TEMPERATURES WILL RANGE FROM THE MID 30S TO NEAR 40 ACROSS THE MOUNTAINS WITH MID 40S TO NEAR 50 DEGREES FOR THE PIEDMONT. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/... AS OF 330 PM EST THURSDAY... NEAR SEASONAL TEMPERATURES FOR THE WEEKEND. IN LAYMANS TERMS...THIS MEANS FIND A COAT. INTRUSION OF COLDER CANADIAN AIR WILL OFFSET THE OUR WARM WEATHER...AT LEAST THROUGH THE WEEKEND WITH TEMPERATURES TUMBLING INTO THE TEENS/20S FOR LOWS AND 40S FOR HIGHS. COLD UPPER LEVEL LONGWAVE TROUGH WILL WILL MOVE THROUGH THE EASTERN CONUS FRIDAY NIGHT AND SATURDAY WITH COLDEST OF THE AIRMASS PASSING OVERHEAD FRIDAY NIGHT. 85H TEMPS ARE PROGGED NEAR MINUS 10 DEG C...THEN GRADUALLY MODERATING FOR THE SECOND HALF OF THE WEEKEND. AN EMBEDDED SHORTWAVE TROUGH...UPPER LEVEL DISTURBANCE...WILL ALSO PASS OVERHEAD FRIDAY NIGHT. THIS FEATURE WILL PROVIDE ENOUGH MOISTURE AND LIFT FOR SCATTERED FLURRIES AND SNOW SHOWERS WEST OF THE BLUE RIDGE. SOME LIGHT ACCUMULATIONS OF SNOW ARE POSSIBLE IN THE HIGHLANDS OF WEST VIRGINIA. FOR SATURDAY...THERE MAY BE SOME LINGERING CLOUDS AND FLURRIES IN THE MOUNTAINS...BUT THE MAIN STORY SATURDAY WILL BE THE BLUSTERY NORTHWEST WINDS. 85H WINDS NEAR 50 KTS ARE PROGGED AROUND DAYBREAK SATURDAY...AND THIS MAY RESULT IN WIND GUSTS OF 40-50 MPH...ESPECIALLY ACROSS THE HIGHER ELEVATIONS. AS SUCH...A WIND ADVISORY MAY BE NEED FOR PARTS OF THE AREA LATE FRIDAY NIGHT AND SATURDAY TO ACCOUNT FOR THIS. WINDS WILL DIMINISH BY SUNSET SATURDAY...HIGH PRESSURE PASSING OVERHEAD SATURDAY NIGHT. CLEAR SKIES AND LIGHT WINDS WILL THEN SET STAGE FOR IDEAL RADIATIONAL COOLING CONDITIONS...ESPECIALLY IN THE MOUNTAIN VALLEYS WHERE TEMPS MAY DIP INTO THE TEENS. AFTER A COLD START SUNDAY...TEMPERATURES WILL BEGIN TO TREND IN THE OPPOSITE DIRECTION...SOUTHWEST WINDS ON THE BACK SIDE OF THE HIGH BEGINNING THE WARM AIR ADVECTION PROCESS. && .LONG TERM /MONDAY THROUGH THURSDAY/... AS OF 345 PM EST THURSDAY... TEMPERATURES WILL RECOVER TO ABOVE NORMAL LEVELS NEXT WEEK. HIGH PRESSURE OVER THE WESTERN ATLANTIC WILL BE IN A POSITION TO PROVIDE ANOTHER PROLONGED PERIOD OF SOUTHWEST WINDS ACROSS THE EASTERN CONUS. DAYTIME TEMPERATURES ARE POISED TO RETURN INTO THE 60S BY MID WEEK...POTENTIALLY TESTING 70 FOR PARTS OF THE FORECAST AREA BY CHRISTMAS EVE. AS SUCH...ANY PRECIPITATION DURING THE WEEK WILL BE IN THE FORM OF RAIN. THE PROVERBIAL FLOOD GATES WILL BE OPEN DURING THE WEEK. A COLD FRONT ASSOCIATED WITH A STORM SYSTEM MOVING THROUGH THE GREAT LAKES MONDAY WILL STALL ACROSS THE AREA TUESDAY...BECOMING THE FOCUS FOR SEVERAL WAVES OF LOW PRESSURE TO RIPPLE NORTHEAST ALONG THE FRONTAL ZONE DURING THE WEEK. AS SUCH...WILL SEE A GRADUAL UPSWING IN PROBABILITY FOR RAIN THROUGH MID WEEK AS SOUTHWEST FLOW ALOFT BRINGS WARMTH/MOISTURE NORTHWARD FROM THE GULF COAST REGION. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... AS OF 1140 PM EST THURSDAY... A COLD FRONT WAS MOVING EAST THROUGH THE APPALACHIANS LATE THIS EVENING...AND WILL BE EAST OF KLYH AND KDAN BY 09Z/4AM. WIDESPREAD IFR TO VLIFR CONDITIONS WILL COVER THE REGION OVERNIGHT. ONCE THE NEXT SHORT WAVE TRACKS UP THE FRONT BY 11Z/6AM FRIDAY MORNING...NORTHWEST WINDS WILL INCREASE...LEADING TO DOWNSLOPING AND CLEARING EAST OF THE BLUE RIDGE. HIGH CONFIDENCE THERE WILL RAPID IMPROVEMENT IN CONDITIONS AT KROA/KLYH AND KDAN AFTER 16Z/NOON ON FRIDAY. THIS INCREASE IN NORTHWEST WINDS AND MIXING WILL RESULT IN WIND GUSTS GENERAL FROM 15 TO 25 KNOTS ON FRIDAY AFTERNOON. MODERATE CONFIDENCE ON CEILINGS LIFTING IN THE MOUNTAINS ON FRIDAY. KBLF AND KLWB MAY IMPROVE TO MVFR BY THE END OF THE DAY. ANOTHER SHORT WAVE WILL CROSS THE REGION FRIDAY NIGHT... WHICH WILL ENHANCE UPSLOPE ON THE WEST SIDE OF THE APPALACHIANS. EXPECT DEEP ENOUGH MOISTURE FOR SNOW SHOWERS IN THE FAR WEST. BUT CONFIDENCE IN TIMING OF PRECIPITATION IS LOW. FOR NOW HAVE SNOW SHOWERS AFTER 7PM IN THE KLWB AND KBLF TAFS. .EXTENDED AVIATION DISCUSSION... GUSTY NORTHWEST WINDS CONTINUE INTO FRIDAY NIGHT ON THE BACKSIDE OF THE DEPARTING SYSTEM...WHICH WILL KEEP UPSLOPE IFR/MVFR CLOUDS AND ISOLATED RAIN OR SNOW SHOWERS ACROSS THE MOUNTAINS... ESPECIALLY PARTS OF SOUTHEAST WEST VIRGINIA INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA. SNOW SHOWERS ALONG WITH MVFR CEILINGS ARE LIKELY IN SOUTHEAST WEST VIRGINIA ON FRIDAY NIGHT AND SATURDAY. THE PRESSURE GRADIENT WILL SLACKEN SATURDAY NIGHT INTO SUNDAY AS THE CENTER OF HIGH PRESSURE BUILDS INTO THE REGION. THIS WILL ALSO BRING AN END TO UPSLOPE CLOUDS AND LIGHT PRECIPITATION. VFR CONDITIONS ARE EXPECTED SUNDAY. BY LATE SUNDAY NIGHT INTO MONDAY...THE NEXT COLD FRONT WILL BE ON OUR WESTERN EDGES OF THE FORECAST AREA. LOOK FOR A RETURN OF MVFR CLOUD COVER...STRONGER LOW LEVEL WINDS...AND PRECIPITATION WITH THE APPROACH AND PASSAGE OF THIS FRONT. MONDAY NIGHT INTO TUESDAY...THE FRONT CROSSES THE AREA WITH ITS ASSOCIATED PRECIPITATION AND SUB-VFR CIGS AND VSBYS. && .EQUIPMENT... AS OF 650 PM EST THURSDAY... A COMMUNICATION OUTAGE HAS LIMITED THE DISTRIBUTION OF THE OBSERVATION FROM THE BLUEFIELD AUTOMATED SURFACE OBSERVATION SYSTEM. DATA FROM THIS SITE MAY BE SPORADICALLY UNAVAILABLE. THERE IS NO ESTIMATE FOR WHEN THIS OUTAGE WILL BE REPAIRED. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...AMS/DS SHORT TERM...PM LONG TERM...PM AVIATION...AMS/DS EQUIPMENT...AMS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
316 AM EST SUN DEC 20 2015 .UPDATE... THE LONG TERM AND AVIATION SECTIONS HAVE BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 125 PM EST SAT DEC 19 2015 HIGH PRESSURE OVER THE DEEP SOUTH WILL PROVIDE DRY WEATHER FOR CENTRAL INDIANA THROUGH SUNDAY EVENING. SOUTHERLY WINDS WILL RETURN TO CENTRAL INDIANA ON SUNDAY...ALLOWING FOR A WARMER DAY. LOW PRESSURE AND A COLD FRONT APPROACHING THE GREAT LAKES ON LATE SUNDAY NIGHT AND MONDAY WILL BRING CHANCES FOR RAIN SHOWERS BACK TO CENTRAL INDIANA. EARLY NEXT WORK WEEK...SEVERAL UPPER LEVEL WEATHER DISTURBANCES WILL PUSH ACROSS THE REGION...CONTINUING THE CHANCES FOR RAIN. MILD AIR IS EXPECTED TO REMAIN ACROSS THE REGION THROUGH NEXT WEEK. THIS WILL RESULT IN A WARM AND GREEN CHRISTMAS. && .NEAR TERM /OVERNIGHT/... ISSUED AT 944 PM EST SAT DEC 19 2015 CLEAR SKIES ACROSS CENTRAL INDIANA THIS EVENING WITH HIGH PRESSURE CENTERED OVER EASTERN TENNESSEE. WITH LIGHT FLOW AND A DRY AIRMASS...TEMPS HAVE FALLEN QUICKLY THIS EVENING INTO THE MID AND UPPER 20S AT 0230Z. LITTLE CHANGE NEEDED FOR THE EVENING UPDATE AS CURRENT FORECAST IN EXCELLENT SHAPE. WITH ONLY SOME THIN CIRRUS DRIFTING INTO THE REGION FROM THE WEST AFTER MIDNIGHT...MAIN FOCUS IS ON TEMPS THE REST OF THE NIGHT. DECISION TO TREND LOWS TOWARDS THE COOL END OF GUIDANCE WAS A GOOD CALL...AS MANY AREAS ARE ALREADY WITHIN A COUPLE DEGREES OF FORECAST LOWS. EXPECT LOWS TO BE REACHED AROUND OR SHORTLY AFTER 06Z WITH TEMPS STEADYING OR SLOWLY RISING THEREAFTER AS WARM ADVECTION COMMENCES AND SOUTHERLY WINDS STRENGTHEN TOWARDS DAYBREAK. UTILIZED RUC HOURLY DATA FOR TEMPERATURE INTERPOLATION OVERNIGHT WITH TEMPS RECOVERING INTO THE UPPER 20S AND LOWER 30S BY DAYBREAK. ZONE AND GRID UPDATES OUT. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... ISSUED AT 125 PM EST SAT DEC 19 2015 DRY WEATHER WILL CONTINUE TO BE EXPECTED ON SUNDAY AND SUNDAY NIGHT AS WARM AIR ADVECTION CONTINUES THROUGH THE DAY ON SOUTHWEST FLOW ALOFT. MODEL SUGGEST 850MB TEMPS REACHING NEAR 8C BY 00Z MONDAY. TIME HEIGHT SECTIONS THROUGH THE DAY SUGGEST SATURATION ALOFT...THUS WILL TREND TOWARD A PARTLY CLOUDY SKY. GIVEN THE STRONG WARM AIR ADVECTION AND SOUTHWESTERLY FLOW WILL TREND HIGHS AT OR ABOVE MAVMOS. INCREASING CLOUDS WILL BE EXPECTED ON SUNDAY NIGHT AS MODELS SUGGEST A SHORT WAVE EMBEDDED WITHIN THE SOUTHWEST FLOW ALOFT TO PUSH ACROSS THE STATE AFTER 06Z. FORECAST SOUNDINGS AND TIME TIME HEIGHTS INDICATE DEEP SATURATION. THE 300K GFS ISENTROPIC SURFACE SHOWS A SURGE OF MOISTURE WITH SPECIFIC HUMIDITIES REACHING OVER 4 G/KG ALONG WITH GOOD LIFT. THUS RAIN WILL BE EXPECTED ON SUNDAY NIGHT AFTER 06Z...AND WILL TREND POPS AT OR ABOVE GUIDANCE. GIVEN THE CLOUDS AND EXPECTED PRECIP WILL TREND LOWS WARMER THAN MAVMOS. MODELS SUGGEST THAT ON MONDAY THROUGH TUESDAY THE ASSOCIATED LOW PRESSURE SYSTEM WITH THE COLD FRONT PULLS QUICKLY TO THE NORTHEAST WHILE THE COLD FRONT STALLS AND ELONGATES ACROSS CENTRAL INDIANA AND SOUTHERN INDIANA. MEANWHILE ALOFT...MAINLY QUICK ZONAL FLOW REMAINS IN PLACE...ALLOWING A SERIES OF WEAK SHORT WAVES TO PUSH IN TO THE OHIO VALLEY THROUGH TUESDAY. GIVEN THE POOR ORGANIZATION...BUT DECENT FORCING AND A LINGERING BOUNDARY IN PLACE ACROSS THE AREA...SOME LOW CHANCE POPS WILL BE NEEDED...FOR LIGHT PRECIP EVENTS. WILL STICK CLOSE TO MAVMOS POPS THROUGH TUESDAY AND TREND LOWS WARMER THAN MAVMOS AND STICK CLOSE ON HIGHS. && .LONG TERM /WEDNESDAY THROUGH SATURDAY NIGHT/... ISSUED AT 313 AM EST SUN DEC 20 2015 MODELS DEPICT AND UPPER RIDGE OVER THE EASTERN STATES WITH MEAN TROUGHING TO THE WEST. ON AND OFF CHANCES FOR RAIN WILL PREVAIL THROUGH THE EXTENDED PERIOD AS PERIODIC DISTURBANCES EJECT OUT FROM THE TROUGH AND IMPACT THIS REGION. EARLY ON IN THIS FORECAST PERIOD...A STRONG UPPER WAVE WILL BE PASSING THROUGH THE LOCAL AREA WEDNESDAY INTO WEDNESDAY NIGHT. THERE APPEARS TO BE ENOUGH FORCING AND INSTABILITY ASSOCIATED WITH THIS FEATURE TO WARRANT SOME CHANCES FOR CONVECTION DURING THIS TIMEFRAME. HAVE CONTINUED TO MENTION CHANCES FOR STORMS ALONG WITH LIKELY TO CATEGORICAL POPS. THE NEXT MAJOR DISTURBANCE TO MOVE THROUGH MAY BEGIN AS EARLY AS CHRISTMAS DAY...AND CONTINUE INTO SATURDAY WITH WEAK CHANCES FOR LIGHT RAIN. THERE IS SOME DISAGREEMENT AMONGST THE GUIDANCE SO CONFIDENCE AND THUS POPS ARE LOW AT THIS TIME. && .AVIATION /DISCUSSION FOR THE 200600Z TAF ISSUANCE/... ISSUED AT 313 AM EST SUN DEC 20 2015 0815Z UPDATE...NO CHANGES NEEDED AT THIS TIME. PREVIOUS DISCUSSION FOLLOWS. HIGH CONFIDENCE IN VFR CONDITIONS THROUGH AT LEAST 04Z SUNDAY. PER MODEL RH TIME SECTIONS AND SATELLITE TRENDS...SHOULD ONLY SEE INCREASING CIRRUS OVERNIGHT AND TODAY...AS AN UPPER RIDGE PASSES THROUGH RESULTING IN SOUTHWEST FLOW ALOFT. DO NOT EXPECT FOG AS LATE EVENING DEW POINT SPREADS REMAINED ABOVE 5 DEGREES AND SOUTH WINDS WILL INCREASE TO AROUND 6 KNOTS OVERNIGHT. LOWER CLOUDS AND A FEW RAIN SHOWERS ARE EXPECTED TO MOVE IN AFTER 04Z MONDAY AS SOUTHERLY FLOW BRINGS IN MOISTURE OFF THE GULF AHEAD OF A WESTERN GREAT LAKES AND SOUTHERN PLAINS FRONTAL SYSTEM. THE SOUTHERLY WINDS WILL INCREASE AFTER 15Z TO NEAR 15 KNOTS WITH GUSTS TO 20 TO 25 KNOTS. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...PUMA NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....SMF AVIATION...SMF/MK
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
258 AM CST SUN DEC 20 2015 .SHORT TERM...(Today and Tonight) Issued at 257 AM CST SUN DEC 20 2015 Winds already picking up in the early morning hours, with winds aloft forecast to increase and stay up through the day today. This has kept overnight lows up in the 40s most areas. As the boundary layer mixes out this morning, RAP and GFS suggest winds at the top of the mixed layer are close to 50 kts. As a result, expect high temperatures to make it into the middle/upper50s, and wind speeds to gust near wind advisory criteria of 40 kts. Will hoist a wind advisory for those counties along and south of I-70. Still a chance for some light drizzle and light rain to develop late this morning in the WAA regime, followed by precip chances continuing due to the shortwave trof moving eastward out of the high plains later this evening. These showers could also aid in mixing down some of the stronger wind speeds through the day today. Both GFS and NAM indicating just a few hours with some weak instability in the column in the midnight to 3am timeframe as the stronger lift and cold pool aloft move over the eastern part of the state. Have left thunder out at this time given small window, but is worth mentioning here. As trof moves eastward, cooler air moves in behind and lows fall into he 20s to middle 30s. .LONG TERM...(Monday through Saturday) Issued at 257 AM CST SUN DEC 20 2015 On Monday another mid level trough tracks over the central US, which should not have much effect on the overall weather. Highs will be cooler in the mid to upper 40s. On Tuesday return flow quickly develops as yet another shortwave approaches from the west, which will allow temperatures to warm back into the 50s. This shortwave trough appears to deepen Tuesday night as it passes over the forecast area. Increased moisture and lift as well as an advancing cold front could support rain Wednesday morning and into the afternoon. This precip appears to stay confined to portions of eastern KS. Towards the end of the week a few of the models continue to bring out weak shortwaves that could cause light precip, but confidence in timing and location is low at this point. Models continue to show a strong system over the southern Rockies over the weekend, but also continue to struggle on how to evolve that system. && .AVIATION...(For the 06Z TAFS through 06Z Sunday Night) Issued at 1114 PM CST SAT DEC 19 2015 Wind gusts will slowly increase overnight while 2000 ft AGL winds near 60 kts will cause llws until surface winds can increase after 09Z. It currently appears that any morning and early afternoon low cloud cover will remain scattered or less, so have held off MVFR cigs until deeper moisture and lift moves over TAF sites after 01Z, which will also promote scattered showers through the end of the TAF period. && .TOP Watches/Warnings/Advisories... Wind Advisory from 8 AM this morning to 6 PM CST this evening for KSZ035>040-054>056-058-059. && $$ SHORT TERM...67 LONG TERM...Sanders AVIATION...Barjenbruch
AREA FORECAST DISCUSSION
NWS GOODLAND KS
930 PM MST SAT DEC 19 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 105 PM MST SAT DEC 19 2015 AS OF 2 PM CST...1 PM MST...THE SKY ACROSS THE TRI-STATE REGION IS BECOMING OVERCAST AS CIRRUS SPREADS IN FROM THE SOUTHWEST. TEMPERATURES RANGED FROM THE UPPER 40S OVER NORTHEAST COLORADO AND NORTH CENTRAL KANSAS TO THE UPPER 50S TO NEAR 60 GENERALLY ALONG THE KANSAS/COLORADO BORDER. WINDS ARE SOUTH TO SOUTHWEST AT 10 TO 15 MPH. AT THE SURFACE...A LEE TROUGH IS CENTERED NEAR THE DENVER METRO AREA WHILE SURFACE HIGH PRESSURE RESIDES OVER THE SOUTHEASTERN UNITED STATES. ALOFT...A TROUGH OF LOW PRESSURE IS MAKING LANDFALL ALONG THE CALIFORNIA COASTLINE. ACCORDING TO WATER VAPOR IMAGERY...A RICH PLUME OF MOISTURE ALOFT EXTENDS FROM THE EAST CENTRAL PACIFIC OCEAN TO SOUTHERN COLORADO. FOR TONIGHT THROUGH TOMORROW...ABOVE NORMAL TEMPERATURES AND DRY WEATHER ARE EXPECTED TO PERSIST. THE MOISTURE ADVECTION FROM THE PACIFIC OCEAN PREVIOUSLY MENTIONED WILL ONLY RESULT IN WIDESPREAD PARTLY CLOUDY/OVERCAST SKIES DUE TO CIRRUS. A WEAK COLD FRONT SHOULD MOVE INTO THE REGION TOMORROW AFTERNOON. HOWEVER...DUE TO THE LATER ARRIVAL OF THE FRONT...ANTICIPATE WARMER TEMPERATURES SIMILAR TO WHAT HAS OCCURRED TODAY. WITH LITTLE TO NO MOISTURE BELOW 500 MB...DRY WEATHER IS ASSURED. SOUTH WINDS THIS AFTERNOON GRADUALLY VEER TO THE WEST TONIGHT BEFORE SHIFTING TO THE NORTHWEST BEHIND THE COLD FRONT. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 105 PM MST SAT DEC 19 2015 FOR THE TAIL-END OF THIS WEEKEND RIGHT ON THROUGH THE UPCOMING WEEK...THE TRI STATE REGION WILL SEE MAINLY DRY CONDITIONS INTO FRIDAY WITH THE CHANCE FOR LIGHT WINTRY PRECIPITATION FRIDAY NIGHT INTO THE DAY SATURDAY. MID LEVEL FLOW DURING THE WEEK WILL START OFF MAINLY WNW WITH A SHIFT TO THE WSW AS A CUTOFF LOW MOVES FROM THE PACIFIC COAST INTO THE CENTRAL/SOUTHERN ROCKIES. BEFORE THE SHIFT TO MORE WSW...THERE WILL BE A FEW SYSTEMS MOVING EAST THRU THE FLOW. THESE LOWS WILL PASS WAY TO OUR NORTH. LOW-LEVEL MODEL RH READINGS(W-NW DOWNSLOPE) PUT AIRMASS TOO DRY SUNDAY NIGHT INTO FRIDAY TO OTHER THAN PUT SOME MID LEVEL CLOUDS OVER THE REGION. THE ARRIVAL OF THE CUTOFF SYSTEM BY THE END OF THE WEEK WILL GIVE THE AREA THE NEXT BEST CHANCE FOR PRECIPITATION. HIGH PRESSURE OVER THE SOUTHEAST PORTION OF THE COUNTRY...COMBINED WITH SURFACE LOW OUT AHEAD OF THE UPPER SYSTEM OVER SW TEXAS...WILL ALLOW FOR LOW LEVEL MOISTURE TO FUNNEL INTO THE SOUTHERN/CENTRAL PLAINS. THE POSITIONING OF THE LOW WILL BE KEY TO HOW MUCH PRECIP THE REGION WILL RECEIVE. MODEL TREND IS FOR NOW TO KEEP SYSTEM TOO FAR SOUTH KEEPING BULK OF MOISTURE AWAY FROM REGION. THE RESULT WILL BE SLIGHT CHANCE FOR -SW. 0-DEGREE ISOTHERM WILL MEANDER OVER THE REGION DURING THIS TIMEFRAME...SO AREA COULD SEE A -RW MIX/CHANCE ESPECIALLY SE ZONES CLOSEST TO WARMER AIRMASS. LIGHT QPF POTENTIAL WILL ONLY GIVE AREA LIGHT SNOWFALL POTENTIAL AT THIS TIME...BUT COULD CHANGE AS WEEK PROGRESSES AND MODELS SHIFT POSITION OF UPPER LOW. FOR TEMPS...ABOVE NORMAL HIGHS IN THE MID 40S TO MID 50S RANGE WILL PERSIST FOR ALL AREAS...WITH 30S ON SATURDAY AS REGION JUST NORTH OF WARMER AIR WITH SYSTEM TO THE SOUTH. OVERNIGHT LOWS WILL RANGE MAINLY IN THE 20S...COLDEST OVER EASTERN COLORADO. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 930 PM MST SAT DEC 19 2015 FOR KGLD AND KMCK...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. WINDS AT KGLD FROM THE SOUTHWEST NEAR 12KTS FROM TAF ISSUANCE THROUGH 08Z THEN A GRADUAL VEERING TO THE WEST-NORTHWEST BY 15Z...NORTHWEST FROM 20Z THROUGH THE REST OF THE TAF PERIOD. SPEEDS GENERALLY UNDER 10KTS. FOR KMCK...LIGHT AND VARIABLE WINDS FROM TAF ISSUANCE THROUGH 17Z THEN NORTHWEST 6-10KTS FROM 18Z THROUGH THE REST OF THE TAF PERIOD. MID AND MOSTLY HIGH CLOUDS EXPECTED THROUGH THE PERIOD. HAVE A BIT OF CONCERN IN THE 22Z-04Z TIMEFRAME AT BOTH TERMINALS. ITS DURING THIS TIME THAT AN UPPER TROUGH OF LOW PRESSURE MOVES ACROSS THE AREA. NAM MOISTURE CROSS SECTIONS SHOW LOW LEVEL MOISTURE INCREASING WITH THE TROUGH PASSAGE POSSIBLY CREATING SOME MVFR CLOUDINESS AND POSSIBLY SOME LIGHT RAIN SHOWERS. HRRR MODEL ALSO SHOWING SOME LIGHT PRECIP AS WELL. WILL HOLD OFF ON INTRODUCING ANY PRECIP MENTION AS CURRENT FORECAST IS DRY. WILL ALSO HOLD OFF ANY SUB VFR CLOUDINESS AS THE NAM APPEARS TO BE THE ONLY MODEL SHOWING MVFR CIGS AT PRESENT TIME. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...RRH LONG TERM...JN AVIATION...99
AREA FORECAST DISCUSSION
NWS JACKSON KY
345 AM EST SUN DEC 20 2015 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 345 AM EST SUN DEC 20 2015 07Z SFC ANALYSIS SHOWS HIGH PRESSURE STARTING TO SLIP OFF TO THE EAST. BEFORE IT GOES IT IS GIVING THE AREA ONE MORE CHILLY NIGHT ALONG WITH A DECENT SIZED RIDGE TO VALLEY TEMPERATURE SPLIT. CLEAR SKIES BENEATH THE HIGH ALONG WITH LIGHT SFC WINDS AND A DRY AIR MASS HAS RESULTED IN VALLEY TEMPERATURES HAVEN FALLEN TO NEAR 20 DEGREES. MEANWHILE...THE RIDGES ARE CLOSER TO FREEZING WHILE DEWPOINTS THROUGHOUT THE AREA ARE CROWDING THE 20 DEGREE MARKER. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST. THEY ALL DEPICT A FLAT RIDGE CROSSING THE TENNESSEE VALLEY WITH HEIGHT RISES ON TAP FOR KENTUCKY TODAY. A SHORTWAVE TROUGH WILL THEN MOVE INTO THE SOUTHERN PLAINS TONIGHT PLACING OUR AREA DOWNSTREAM IN BROAD SOUTHWEST FLOW. SOME WEAK ENERGY WAVES WILL PASS THROUGH EASTERN KENTUCKY BY MONDAY MORNING WITH THE MAIN WAVE TAKING A TRACK TO THE NORTHWEST OF KENTUCKY. SOUTHWEST FLOW WILL CONTINUE INTO MONDAY EVENING AS ANOTHER TROUGH AND ENERGY BATCH HEAD FOR THE STATE FROM THE WEST. GIVEN THE GENERAL MODEL AGREEMENT HAVE AGAIN FAVORED THE HIGHER RESOLUTION HRRR AND NAM12 FOR WEATHER DETAILS. SENSIBLE WEATHER WILL FEATURE ANOTHER CHILLY START THIS MORNING... BUT PLENTY OF SUNSHINE WILL OVERCOME THAT YIELDING AFTERNOON TEMPERATURES IN THE 50 TO 55 DEGREE RANGE. HIGH CLOUDS WILL ARRIVE AND THICKEN WITH TIME THIS AFTERNOON INTO THE NIGHT AHEAD OF A QUICK MOVING COLD FRONT INBOUND FROM THE WEST. THIS FRONT WILL BRING ANOTHER ROUND OF SHOWERS TO THE CWA FOR MONDAY...THOUGH THE BEST MOISTURE AND HIGHEST PCPN CHANCES SPLIT THE AREA TO THE NORTH AND SOUTH. WHILE SOME EASTERN VALLEYS WILL FALL BELOW FREEZING TONIGHT...EXPECT THE FRONT/S APPROACH TO STIR THE AIR ENOUGH TO KEEP THEM FROM BEING THAT COLD WHEN THE FIRST RAIN CHANCES ARRIVE...SO HAVE LEFT ANY MIX CHANCES OF PCPN OUT OF THE FORECAST FOR NOW. THE FRONT WILL THEN STALL OVERHEAD THAT WITH THE NEXT SURGE OF MOISTURE LIKELY RIDING NORTH INTO THIS PART OF THE STATE LATER MONDAY NIGHT. FOR TEMPERATURES AND DEWPOINTS...HAVE AGAIN STARTED WITH THE SHORTBLEND GRIDS THROUGH TONIGHT FOLLOWED BY THE SUPERBLEND INTO MONDAY EVENING. DID AGAIN MAKE SOME MORE SIGNIFICANT ADJUSTMENTS TO THE LOWS TONIGHT...ESPECIALLY IN THE EASTERN VALLEYS DUE TO THE ANTICIPATION OF AN EARLY TEMPERATURE DROP OFF THIS EVENING FOLLOWED BY RISING TEMPS TOWARD DAWN FOR THE MOST SHELTERED LOCATIONS. AS FOR POPS...ENDED UP ON THE HIGHER SIDE OF ALL MOS FOR MONDAY...BUT CLOSEST TO THE MAV NUMBERS. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 315 AM EST SUN DEC 20 2015 VERY MILD AND POTENTIALLY RECORD BREAKING WARMTH WILL REMAIN THE MAIN HEADLINE AS WE HEAD THROUGH CHRISTMAS WEEK. IN ADDITION TO THE WARMTH...PLENTY OF CHANCES FOR RAIN WILL BE SEEN. STRONG RIDGING WILL BE IN PLACE ACROSS THE EASTERN CONUS THROUGH ALL OF CHRISTMAS WEEK. STARTING OFF TUESDAY NIGHT...A POTENT SHORTWAVE WILL MOVE NORTHEAST ACROSS THE OHIO RIVER VALLEY ALONG A STALLED OUT COLD FRONT. THIS WILL BRING INCREASING RAIN CHANCES THROUGH THE OVERNIGHT HOURS. FORCING WITH THIS WAVE WILL EXIT NORTH EARLY TUESDAY MORNING...WITH SUBSIDENCE BUILDING IN BEHIND THE DEPARTING WAVE ON TUESDAY. TEMPERATURES WILL CLIMB INTO THE 60S ON TUESDAY ALTHOUGH WE`LL HAVE A TOUGH TIME GETTING RID OF THE CLOUDS. A SECONDARY WAVE WILL LIFT NORTH TUESDAY NIGHT AND BRING ANOTHER ROUND OF RAIN SHOWERS TO EASTERN KENTUCKY. STILL SOME UNCERTAINTY ON THE EXTENT OF RAIN CHANCES AND HOW SOUTHEAST DOWNSLOPING FLOW IMPACTS OUR RAIN CHANCES. HOWEVER...WILL GO WITH HIGHEST POPS IN THE WEST...TO LOWER POPS IN THE EAST. ON WEDNESDAY...WE MAY SEE ANOTHER LULL AS SUBSIDENCE SPREADS BACK IN BEHIND THE DEPARTING WAVE. WITH EVEN WARMER BOUNDARY LAYER CONDITIONS IN PLACE...WE COULD BE EASILY PUSHING 70...WITH GUIDANCE SUGGESTING WIDESPREAD LOWER 70S. THIS WOULD EXCEED OUR RECORDS FOR WEDNESDAY BY 5 TO 8 DEGREES. FINALLY...A COLD FRONT WILL WORK EAST ACROSS THE AREA WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING...BRINGING ANOTHER SURGE OF RAIN. THIS TIME AROUND...THE FRONT SHOULD MOVE ON EAST...BRINGING A TEMPORARY END TO THE RAIN CHANCES. HIGH PRESSURE SHOULD KEEP THE WEATHER DRY FROM LATE THURSDAY MORNING THROUGH CHRISTMAS MORNING. HOWEVER...MODELS ARE TRENDING FASTER WITH BRINGING RAIN CHANCES. IF THIS OCCURS...WE WILL CERTAINLY BRING POPS BACK INTO THE AREA ON CHRISTMAS AS A WARM FRONT QUICKLY SURGES BACK TO THE NORTH. THIS WILL NOT ONLY MEAN A WARMER CHRISTMAS...BUT A WETTER ONE AS WELL. AS WE HEAD INTO THE WEEKEND...MODELS ARE HAVING A TOUGH TIME ON HOW THINGS EVOLVE...BUT CERTAINLY COULD BE SOME WET WEATHER AT SOME POINT OVER THE WEEKEND AS A DEEP SYSTEM ORGANIZES SOMEWHERE OVER THE CENTRAL OR EASTERN US. FOR THIS REASON WILL KEEP SOME CHANCE POPS IN THE FORECAST THROUGH THE WEEKEND. IT DOES LOOK LIKE WE SHOULD REMAIN MILD THROUGH THE WEEKEND...WITH PERHAPS A BRIEF COOL DOWN AS WE HEAD INTO THE FOLLOW WEEK. HOWEVER...THERE IS MUCH UNCERTAINTY IN THE FORECAST BEYOND CHRISTMAS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1250 AM EST SUN DEC 20 2015 HIGH PRESSURE WILL REMAIN IN CONTROL ACROSS THE REGION THROUGH THE TAF PERIOD PROVIDING VFR CONDITIONS UNDER MOSTLY CLEAR SKIES. IN ADDITION...WINDS WILL BE LIGHT AND VARIABLE THROUGH SUNDAY NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GREIF LONG TERM...KAS AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1214 AM EST SUN DEC 20 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD TONIGHT INTO SUNDAY. A WARM FRONT WILL CROSS THE REGION MONDAY. A WEAK AREA OF LOW PRESSURE WILL MOVE NORTH OF THE STATE MONDAY NIGHT INTO TUESDAY. && .NEAR TERM /THROUGH TODAY/... UPDATE: LATEST RADAR REFLECTIVITY SHOWS WHAT`S LEFT OF THE SNOW BANDS ARE WEAKENING, WITH ONE BAND JUST NORTH OF HOULTON AND ANOTHER ONE AFFECTING NRN WASHINGTON COUNTY, IN THE VICINTY OF THE VANCEBORO TO CALAIS AREA. THE LATEST HRRR SHOWS THIS ACTIVITY RAPIDLY DIMINISHING OVER THE NECT COUPLE HOURS WITH THE PASSAGE OF THE UPPER TROF. HAVE UPDATED THE POPS/SKY GRIDS FOR THE OVERNIGHT HOURS TO REFLECT LATEST TRENDS. OTHERWISE, REMAINDER OF THE OVERNIGHT FORECAST STILL LOOKS GOOD. ORGNL DISC: MARKEDLY COLDER AIR WILL CONTINUE TO ADVECT INTO THE REGION TONIGHT WITH THE COLD UPPER TROUGH PASSAGE NEAR MIDNIGHT. UNTIL THIS TROUGH CROSSES...LOW LEVEL INSTABILITY WILL PROMOTE LINES OF SNOW SHOWERS MOVING PARALLEL TO THE UPPER FLOW. CAPE ACTUALLY INCREASES TONIGHT WITH THE TROUGH. THESE SNOW SHOWERS WILL BE MOSTLY NORTH OF HOULTON THROUGH THE EVENING BUT GUIDANCE SUGGEST A BAND COULD CROSS DOWN EAST LATE IN THE EVENING. LITTLE OR NO ACCUMULATION IS EXPECTED. THE PRIMARY CONCERNS WILL BE REDUCED VISIBILITY AND STRONG WIND GUSTS UP TO 40 MPH TONIGHT. THIS WILL CREATE HAZARDOUS CONDITIONS FOR MOTORISTS. THE CURRENT SPECIAL WEATHER STATEMENT FOR THE SNOW SHOWERS MAY NEED TO BE EXTENDED THROUGH THE EVENING. SOME SNOW SHOWERS COULD BE MORE PROLONGED THIS EVENING AS THE UPPER TROUGH CROSSES FOR NORTHERN AROOSTOOK. ONCE THE UPPER TROUGH PASSES...SKIES WILL CLEAR BUT WINDS WILL REMAIN VERY STRONG THROUGH SUNDAY MORNING. SUNDAY WILL FEATURE THE COLDEST HIGH TEMPERATURES OF THE MONTH TO DATE WITH READINGS IN THE LOW 20S NORTH AND UPPER 20S TO NEAR 30F FOR BANGOR AND DOWN EAST. WIND CHILLS SUNDAY MORNING WILL BE NEAR ZERO...A SIGNIFICANT CONTRAST TO RECENT DAYS. && .SHORT TERM /TONIGHT THROUGH TUESDAY/... HIGH PRESSURE MOVING OFF THE EAST COAST SUNDAY NIGHT COMBINED WITH WEAK LOW PRESSURE APPROACHING FROM THE GREAT LAKES WILL BRING WARM ADVECTION TOWARD THE AREA ON MONDAY. SOME SPOTTY LIGHT SNOW WILL BE POSSIBLE ACROSS THE FAR NORTH SUNDAY NIGHT. SOME LIGHT PRECIPITATION IN THE FORM OF SNOW OVER THE NORTH AND LIGHT RAIN DOWNEAST WITH SOME SLEET AND FREEZING RAIN POSSIBLE IN CENTRAL AREAS WILL SPREAD ACROSS THE REGION MONDAY AS THE LOW MOVES IN. THE LOW WILL LIFT TO OUR NORTHWEST MONDAY NIGHT AND WEAKEN. SPOTTY LIGHT MIXED PRECIPITATION WILL BE POSSIBLE IN THE NORTH WITH RAIN SHOWERS OR DRIZZLE IN CENTRAL AND SOUTHERN AREAS. A WEAK WARM FRONTAL BOUNDARY WILL REMAIN OVER THE AREA TUESDAY BRINGING A CONTINUATION OF CLOUDY CONDITIONS WITH SOME SPOTTY RAIN SHOWERS POSSIBLE. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... HIGH PRESSURE OVER THE MARITIMES WILL BRIEFLY NUDGE OVER THE REGION TUESDAY NIGHT INTO WEDNESDAY BUT THE AIR WILL REMAIN MILD WITH LONGWAVE RIDGING ANCHORED OVER THE EAST. A LARGE STORM SYSTEM TRACKING ACROSS THE NORTH CENTRAL PART OF THE COUNTRY WILL APPROACH WEDNESDAY NIGHT INTO THURSDAY PULLING WARMER AIR INTO THE REGION AS THE SYSTEM LIFTS INTO SOUTHERN CANADA. SOME SHOWERS, FOG AND DRIZZLE WILL BE LIKELY WEDNESDAY NIGHT INTO THURSDAY WITH UNSEASONABLY WARM AIR ACROSS THE REGION. A COLD FRONT WILL COME THROUGH THURSDAY NIGHT. GUSTY WEST WINDS AND MODERATELY COOLER CONDITIONS WILL PREVAIL FOR CHRISTMAS DAY AS THE LOW TRACKS INTO THE NORTHERN PART OF EASTERN CANADA. && .AVIATION /05Z SUNDAY THROUGH THURSDAY/... NEAR TERM: SNOW SHOWERS WILL GENERATE THE RISK OF TEMPO LIFR CONDITIONS AND A LOT OF LOW LEVEL TURBULENCE THIS EVENING...MOSTLY FROM PQI NORTHWARD. OTHERWISE...VFR CONDITIONS ARE EXPECTED WITH VERY GUSTY NW WINDS UP TO 40 MPH. THE WINDS WILL FURTHER INCREASE TONIGHT AND CONTINUE INTO SUNDAY MORNING. THE WINDS WILL DECREASE SUNDAY AFTERNOON. SHORT TERM: CONDITIONS WILL LIKELY DROP TO MVFR IN STRATUS CLOUDS SUNDAY NIGHT THEN BE MVFR TO IFR MONDAY INTO MONDAY NIGHT IN LOW CLOUDS. MVFR CONDITIONS ARE LIKELY TUESDAY INTO TUESDAY NIGHT. CONDITIONS MAY IMPROVE TO VFR DOWNEAST LATE TUESDAY NIGHT. VFR CONDITIONS ARE LIKELY WEDNESDAY. A RETURN TO IFR IN LOW CLOUDS IS THEN EXPECTED WEDNESDAY NIGHT INTO THURSDAY IN LOW CLOUDS. && .MARINE... NEAR TERM: THE GALE IS STILL EXPECTED WITH WIND GUSTS INCREASING TOWARDS 40 KTS LATER TONIGHT INTO SUNDAY MORNING. SEAS ARE EXPECTED TO REACH AS HIGH AS 10 FEET. SHORT TERM: A GALE MAY BE NEEDED ON MONDAY FOR GUSTY WEST WINDS. AN SCA OR GALE WILL LIKELY BE NEEDED AGAIN CHRISTMAS EVE INTO CHRISTMAS DAY FOR STRONG GUSTY SOUTH WINDS BECOMING WESTERLY. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...GALE WARNING UNTIL 10 AM EST THIS MORNING FOR ANZ050>052. && $$ NEAR TERM...DUDA/VJN SHORT TERM...BLOOMER LONG TERM...BLOOMER AVIATION...DUDA/VJN/BLOOMER MARINE...DUDA/VJN/BLOOMER
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1204 AM EST SUN DEC 20 2015 .SYNOPSIS... BANDS OF LAKE EFFECT SNOW WILL CONTINUE SOUTH AND EAST OF LAKE ONTARIO OVERNIGHT. HIGH PRESSURE WILL THEN BUILD ACROSS THE LOWER GREAT LAKES SUNDAY...BRINGING A RETURN TO DRY WEATHER AND WARMER TEMPERATURES SUNDAY. A SERIES OF STORM SYSTEMS CROSSING THE GREAT LAKES WILL BRING A RETURN TO WET AND UNSEASONABLY MILD TEMPERATURES FOR MUCH OF THE COMING HOLIDAY WEEK. && .NEAR TERM /THROUGH TODAY/... LAKE EFFECT SNOW EAST OF LAKE ERIE WEAKENED EARLY THIS EVENING IN RESPONSE TO A LOWERING SUBSIDENCE INVERSION. 00Z KBUF SOUNDING SHOWED THIS INVERSION AT 6KT. THE INVERSION LEVEL OVER LAKE ONTARIO SHOULD BE CLOSER TO 8KFT /PER 00Z NAM BUFKIT/ WHICH WILL CONTINUE TO SUPPORT A SEVERAL BROKEN DISORGANIZED BANDS OF LAKE EFFECT SNOW THROUGH MUCH OF THE OVERNIGHT HOURS. LATEST RADAR SHOWS SNOW SHOWERS WITH A LAKE HURON CONNECTION ON WESTERLY FLOW STRETCHING DOWN THE LONG AXIS OF THE LAKE. LIGHT SNOW SHOWERS ARE FALLING ALONG THE SOUTHERN LAKE ONTARIO SHORE COUNTIES WHERE THE FORECAST HAS BEEN UPDATED WITH 2-3 INCHES OF SNOWFALL. THE MOST INTENSE RETURNS STRETCHING WEST TO EAST ACROSS OSWEGO AND SOUTHERN LEWIS COUNTIES. THERE IS A POTENTIAL FOR ANOTHER 2-4 OR SO INCHES OVERNIGHT ACROSS CENTRAL AND SOUTHERN OSWEGO AND SOUTHERN LEWIS COUNTIES. GIVEN THE SLOW SOUTHERLY TREND TO THE BAND AS WINDS VEER...A LAKE EFFECT SNOW ADVISORY CONTINUES FOR NORTHERN CAYUGA COUNTY THROUGH 12Z SUNDAY FOR 2-4 MORE INCHES OF SNOW. THERE IS HOWEVER SEVERAL VERY NARROW SNOW BANDS WITH A GEORGIAN BAY CONNECTION PRESSING SOUTH ACROSS JEFFERSON COUNTY. ONLY EXPECT AN ADDITIONAL INCH OR TWO OF ACCUMULATION WITH THIS OVERNIGHT BEFORE IT MERGES WITH THE SOUTHERN BAND PER 01Z/20 HRRR RUN AND 12Z/19 RGEM MODEL. OUTSIDE OF LAKE EFFECT BANDS...WE MAY SEE A FEW FLURRIES ON THE EDGE OF THE BANDS. CLOUD COVER AND INCREASING WARM ADVECTION...ESPECIALLY ACROSS WESTERN NEW YORK...WILL LIMIT TEMPERATURE FALLS OVERNIGHT WITH LOWS IN THE 20S. AS WE MOVE INTO SUNDAY...A SURFACE RIDGE WILL TRANSIT THE FORECAST AREA...BRINGING AN END TO ANY LINGERING SNOWS DURING THE FIRST PART OF THE MORNING. THE AFTERNOON SHOULD FEATURE DECREASING CLOUD COVER...THOUGH WITH WARM ADVECTION BEGINNING TO TAKE HOLD ACROSS THE AREA...WE MAY SEE MID/HIGH CLOUDS INCREASE LATER IN THE DAY. TEMPERATURES WILL RISE BACK ABOVE FREEZING ACROSS THE BULK OF THE FORECAST AREA AS AFOREMENTIONED WARM ADVECTION TAKES HOLD AS THE CENTER OF THE SURFACE HIGH MOVES OFF THE EAST COAST. && .SHORT TERM /TONIGHT THROUGH TUESDAY/... SUNDAY NIGHT SURFACE HIGH PRESSURE WILL BE FOUND JUST TO OUR EAST...WITH A SOUTHERLY FLOW OF WIND ON THE FEATURES WESTERN FLANK. IT SHOULD BE A QUIET NIGHT...WITH TEMPERATURES DROPPING EARLY INTO THE UPPER 20S AND LOWER 30S. THE SOUTHERLY WIND...INCREASING CLOUDS FROM THE WEST AND WARM AIR ADVECTION SHOULD ALLOW FOR SURFACE TEMPERATURES TO RISE A FEW DEGREES AFTER MIDNIGHT. THE NEXT STORM SYSTEM WILL BE AN AREA OF LOW PRESSURE TRACKING FROM THE PLAINS SUNDAY NIGHT...AND THROUGH THE CENTRAL GREAT LAKES ON MONDAY. AHEAD OF THIS SYSTEM A LLJ WILL BE STRENGTHENING TO 50 TO 60 KNOTS. CONVERGENCE AHEAD OF THIS JET...COMBINED WITH A SHORTWAVE RIPPLING SOUTHWEST TO NORTHEAST THROUGH THE LOW GREAT LAKES REGION WILL DEVELOP AN AREA OF RAIN SHOWERS. THE RISE IN SURFACE TEMPERATURES LATE SUNDAY NIGHT SHOULD PUSH ALL AREAS ABOVE FREEZING AT THE ONSET OF THE PRECIPITATION MONDAY...AND WILL HAVE JUST PLAIN RAIN SHOWERS IN THE GRIDS. MONDAY WILL ALSO BECOME BREEZY AS THIS LLJ BEGINS TO MIX DOWN TO THE SURFACE...ESPECIALLY DOWNWIND OF THE GREAT LAKES. GUSTS UP TO 40 MPH WILL BE POSSIBLE ACROSS THE TRADITIONAL WINDY LOCATIONS NORTHEAST OF THE LAKES. THE SURFACE LOW TO THE WEST WILL REMAIN NEUTRAL...OR SLOWLY FILL WHICH WILL LIMIT THE AGEOSTROPHIC COMPONENT OF THE WIND...AIDING TO LIKELY KEEP GUSTS BELOW ADVISORY CRITERIA. MONDAY NIGHT AND TUESDAY THIS LOW WILL WEAKEN AS IT DRIFTS BY TO OUR NORTH ACROSS SOUTHERN CANADA. A WEAK COLD FRONT WILL PASS INTO OUR REGION LATE MONDAY AND TUESDAY...SERVING AS A BOUNDARY FOR CONTINUED SCATTERED LIGHT RAIN SHOWERS. CLOUD COVER MONDAY NIGHT WILL HOLD TEMPERATURES TO THE 40S FOR OVERNIGHT LOWS...WHILE ON TUESDAY TEMPERATURES WILL REBOUND BACK INTO THE UPPER 40S...WITH A FEW SPOTTY 50 READINGS. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... BASED ON THE 18Z GFS/12Z ECMWF AND THE UNSEASONABLY WARM SOUTHERLY FLOW FORECAST WE HAVE RAISED HIGH TEMPERATURES FOR WED/THU A FEW DEGREES. NO OTHER CHANGES ON THE EVENING UPDATE. TEMPERATURES WILL TRANSITION TO MUCH ABOVE SEASONAL NORMALS AT THE START OF THIS PERIOD. A FAST NORTHERN PACIFIC FLOW WILL CARRY CLUSTERS OF ENERGY ACROSS THE ROCKIES...DEEPENING A LONG WAVE TROUGH OVER THE CENTRAL PLAINS BY TUESDAY NIGHT. DOWNSTREAM...A RIDGE OF HIGH PRESSURE WILL DEVELOP OVER THE EASTERN US AND SOUTHERN CANADA. WITHIN THIS RIDGE A SOUTHERLY FLOW WILL BUILD WARMTH...AS WELL AS CARRY MOISTURE FROM THE SOUTH NORTHWARD. AT THE SURFACE A WEAK AREA OF HIGH PRESSURE WILL YIELD A MAINLY DRY TUESDAY NIGHT. SOUTHERLY FLOW WILL AGAIN MAINTAIN TEMPERATURES IN THE UPPER 30S TO LOWER 40S OVERNIGHT. ON WEDNESDAY EXPECT RAIN SHOWERS TO AGAIN RETURN TO THE REGION AS BUILDING MOISTURE AHEAD OF THE UPSTREAM TROUGH BUILDS OVER OUR REGION. PWATS WILL CLIMB TO AROUND AN INCH ON WEDNESDAY. A SHORTWAVE IN ADVANCE OF THE MAIN UPSTREAM TROUGH WILL CREST THE UPPER LEVEL RIDGE OVER THE EAST WEDNESDAY...PROVIDING ENOUGH LIFT TO GENERATE A WIDE AREA OF RAIN SHOWERS OVER THE NORTHEAST. WILL CONTINUE WITH LIKELY POPS WEDNESDAY...WITH THESE LIKELY POPS CARRYING THROUGH THURSDAY. THURSDAY AND INTO EARLY FRIDAY THIS PLAINS TROUGH WILL BEGIN TO PUSH EASTWARD. MEANWHILE AT THE SURFACE IT WILL SPAWN A STORM SYSTEM OVER THE CENTRAL PLAINS. MODELS CONTINUE TO TAKE THE TRACK OF THE LOW TO OUR NORTH...WHILE BRINGING A COLD FRONT ACROSS THE REGION ON THURSDAY. RAIN SHOWERS ALONG THE FRONT WILL TAPER OFF THURSDAY NIGHT FOLLOWING THE PASSAGE OF THE COLD FRONT. THE AIR BEHIND THE FRONT WILL BE COLDER...BUT NOT SUCH TO SUPPORT ANY LAKE EFFECT SNOW RESPONSE. THERE MAY HOWEVER BE SOME LAKE EFFECT CLOUDINESS AND LIGHT RAIN SHOWERS. ON FRIDAY HIGH PRESSURE BEHIND THE COLD FRONT WILL MOVE INTO THE GREAT LAKES REGION. THIS WILL END THE PRECIPITATION...WHILE ALSO SUPPLING THE REGION WITH A FRESH COLD AIRMASS. THIS DRIER AIRMASS MAY ALLOW FOR A MOSTLY SUNNY CHRISTMAS DAY. TEMPERATURES ALOFT WILL LIKELY NOT BE COOL ENOUGH FOR ANY LAKE EFFECT SNOW. IN REGARDS TO TEMPERATURES CHRISTMAS EVE...AND CHRISTMAS DAY...THE 24TH WILL BE THE WARMER OF THE TWO DAYS WITH HIGHS WELL INTO THE 50S...AND POSSIBLY 60F. FEEL COMFORTABLE WITH SURFACE TEMPERATURES NEAR RECORD HIGHS THURSDAY AS 850 HPA TEMPERATURES OF THIS MAGNITUDE WILL BE NEAR THE WARMEST TEMPERATURES MEASURED BY WEATHER BALLOONS ON THIS DATE/MOVING AVERAGE...AND DESPITE THE THICK CLOUD COVER...THE LOW SUN ANGLE HAS THE LEAST EFFECT ON DAYTIME HEATING THIS TIME OF YEAR. A LIST OF RECORD HIGHS CAN BE FOUND IN THE CLIMATE SECTION BELOW. ON FRIDAY BEHIND THE COLD FRONT AIR TEMPERATURES WILL RETURN TO NEAR...ALBEIT STILL ABOVE...SEASONAL VALUES WITH HIGHS IN THE LOW TO MID 40S. THERE IS MODEL UNCERTAINTY AS WE HEAD INTO NEXT WEEKEND REGARDING THE PLACEMENT OF THE NEXT UPPER LEVEL TROUGH. THE 12Z GFS MAINTAINS A CLOSED LOW OVER THE DESERT SOUTHWEST AND EVEN INTO MEXICO...WHILE THE 12Z ECMWF IS MORE PROGRESSIVE WITH THE FLOW...WITH A TROUGH OVER THE SOUTHERN PLAINS. FOR NOW WILL HAVE CHANCE WORDING IN THE FORECAST...FAVORING THE 12Z ECMWF...AS IT IS PRETTY RARE FOR A CLOSED UPPER LEVEL LOW AT 500 HPA TO TRACK AND PERSIST AS LONG AS THE 12Z GFS HAS OVER NORTHERN MEXICO. && .AVIATION /05Z SUNDAY THROUGH THURSDAY/... LAKE EFFECT SNOW HAS TAPERED OFF EAST OF LAKE ERIE AT 05Z WITH MVFR CIGS AT KJHW. SOUTH AND SOUTHEAST OF LAKE ONTARIO...LAKE EFFECT SNOW BANDS WILL CONTINUE THROUGH THE OVERNIGHT WITH A FEW OF THESE VERY NARROW BANDS OF SNOW DRIFTING SOUTH ACROSS JEFFERSON COUNTY WHICH MAY BRING TEMPO VIS/CIG REDUCTIONS AS IT SETTLE SOUTH OVERNIGHT. LAKE EFFECT SNOW WILL DIMINISH AFTER 12Z ACROSS OSWEGO AND NORTHERN CAYUGA COUNTIES SUNDAY WITH IMPROVEMENT TO VFR BY THE END OF THE PERIOD. ELSEWHERE...LOOK FOR VFR CONDITIONS TO PERSIST WITH CIGS RISING AS FLOW BACKS TO THE SOUTH ON SUNDAY. STRONG WINDS WILL ALSO DIMINISH LATE TONIGHT WITH THE ARRIVAL OF SURFACE HIGH PRESSURE AND INCREASING WARM ADVECTION. SUNDAY EVENING A 50KT LOW LEVEL JET WILL SHIFT OVER WESTERN NEW YORK WITH LOW LEVEL WIND SHEAR EXPECTED. THIS HAS BEEN INCLUDED IN THE 06Z TAFS. OUTLOOK... MONDAY...VFR/MVFR WITH RAIN SHOWERS LIKELY. TUESDAY...MAINLY VFR WITH A CHANCE OF RAIN SHOWERS. WEDNESDAY AND THURSDAY...VFR/MVFR WITH RAIN SHOWERS LIKELY. && .MARINE... WINDS ON ERIE AND ONTARIO ARE ALL SUB-GALE WITH A TIGHT PRESSURE GRADIENT BETWEEN A SURFACE HIGH BUILDING INTO THE OHIO VALLEY AND LOW PRESSURE OVER THE CANADIAN MARITIMES. WINDS WILL BRIEFLY SUBSIDE SUNDAY AS HIGH PRESSURE MOVES ACROSS THE LOWER GREAT LAKES. SOUTH-SOUTHWEST FLOW WILL THEN RE-DEVELOP ACROSS THE LOWER GREAT LAKES MONDAY IN ADVANCE OF A COLD FRONT THAT WILL CROSS THE LAKES MONDAY. THIS WILL EVENTUALLY REQUIRE ANOTHER ROUND OF SMALL CRAFT ADVISORIES FOR THE EASTERN ENDS OF THE LAKES. && .CLIMATE... ALTHOUGH BUFFALO HAS GOTTEN ITS FIRST MEASURABLE SNOW...THIS WINTER CONTINUES TO BE OFF TO AN EXTRAORDINARLY WARM START. MORE UNSEASONABLE WARMTH EXPECTED NEXT WEEK. ANOTHER VERY WARM AIRMASS WILL BRING NEAR RECORD HIGHS ON WEDNESDAY AND THURSDAY (CHRISTMAS EVE). LISTED BELOW ARE THE RECORDS... WEDNESDAY... CITY.........RECORD HIGH (F)....RECORD WARM LOW (F)..... BUFFALO......59 / 1957...........46 / 1941 ROCHESTER....60 / 1957...........43 / 2006 WATERTOWN....58 / 1990...........42 / 2006 CHRISTMAS EVE... BUFFALO......59 / 1964...........46 / 1979 ROCHESTER....58 / 1982...........47 / 2014 WATERTOWN....59 / 2014...........49 / 2014 WHEN CONSIDERING THE FORECAST THROUGH THE END OF THE MONTH...2015 STANDS A GOOD CHANCE TO BECOME THE WARMEST ON RECORD. CURRENT TRENDS SUGGEST THAT THE MONTHLY AVERAGE TEMPERATURE MAY TOP 40 DEGREES. THIS PUTS THE FOLLOWING RECORDS IN SERIOUS JEOPARDY. WARMEST MEAN TEMPERATURE FOR DECEMBER... CITY TEMP YEAR BUFFALO.....37.6 (1923) ROCHESTER...39.0 (2006) && .EQUIPMENT... THE BUF WSR-88D HAS AGAIN BEEN WORKED ON AND IS OPERATING. HOWEVER THERE ARE STILL SPORADIC ISSUES WHICH MAY IMPACT DATA QUALITY AND TIMELINESS. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...LAKE EFFECT SNOW WARNING UNTIL 7 AM EST THIS MORNING FOR NYZ006-008. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR NYZ005. MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR LEZ040- 041. SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LOZ043>045. SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR LOZ042. && $$ SYNOPSIS...SMITH/WOOD NEAR TERM...SMITH/WOOD SHORT TERM...THOMAS LONG TERM...APFFEL/THOMAS AVIATION...SMITH/WOOD MARINE...SMITH/WOOD CLIMATE...THOMAS/APFFEL EQUIPMENT...THOMAS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1233 AM CST SUN DEC 20 2015 .UPDATE... ISSUED AT 1232 AM CST SUN DEC 20 2015 SURFACE LOW PRESSURE WAS OVER THE WY/SD BORDER WITH ANOTHER WEAKER LOW OVER FAR SOUTHERN SASKATCHEWAN. AT UPPER LEVELS...A LONGWAVE TROUGH WAS OVER THE ROCKIES WITH SOUTHWESTERLY FLOW ALOFT OVER THE WESTERN PLAINS BRINGING SOME WEAK UPPER LEVEL ENERGY IMPULSES OVER THE FRONT RANGE OVER MONTANA AND WYOMING AND OVER THE DAKOTAS. CURRENT RADARS INDICATING WEAK RETURNS FROM SOUTH CENTRAL MONTANA NORTHEASTWARD INTO NORTHWESTERN NORTH DAKOTA. THIS IS LIKELY INDICATIVE OF SOME WEAK UPPER LEVEL ENERGY AND MID LEVEL CLOUDS. NO SURFACE OBSERVATIONS INDICATING ANY PRECIPITATION AT OBSERVATION SITES. THE LATEST MODELS INDICATE THAT THE UPPER LEVEL ENERGY STREAMS SHOULD BEGIN TO SHIFT SOUTH WITH TIME OVERNIGHT...WITH THE SURFACE LOW OVER SOUTHERN SASKATCHEWAN MOVING SOUTHEAST. KEPT THE TRENDS FROM THE PREVIOUS UPDATE WITH THE SLIGHT CHANCE OF LIGHT SNOW NORTHWEST NORTH DAKOTA SHIFTING SOUTHWARD TO SOUTHWESTERN NORTH DAKOTA TOWARDS DAYBREAK. ALSO LOOK FOR AREAS OF FOG AS LATEST HIGH RESOLUTION MODELS INDICATE VARYING CLOUD LAYERS AND VISIBILITIES AS THE LOW/FRONT IN SASKATCHEWAN MOVES SOUTHEAST. TEMPERATURES IN THE SOUTHWEST SHOULD BE FAIRLY STEADY IN THE LOW TO MID 20S...WITH LOWS ELSEWHERE FROM 5 TO 15 ABOVE. UPDATE ISSUED AT 935 PM CST SAT DEC 19 2015 LATEST SATELLITE/RADAR AND SURFACE OBSERVATIONS INDICATE MAINLY MVFR CEILINGS ACROSS FAR NORTHERN NORTH DAKOTA...WITH A PATCH OF IFR CEILINGS OVER NORTHWEST ND INTO NORTHEAST MT. LATEST SURFACE ANALYSIS INDICATES OVERALL WEAK SURFACE PATTERN...BUT LOW PRESSURE OVER SOUTHEAST SASKATCHEWAN...WHICH IS FORECAST TO TRACK SOUTH AND EAST ACROSS THE FORECAST AREA TONIGHT. HAVE ADJUSTED TEMPERATURES LOWER AGAIN...BUT CURRENT T/TD SPREADS ARE CLOSE AND INCREASING WARM ADVECTION/CLOUDS AND POSSIBLY LIGHT SNOW SPREADING WEST TO EAST SHOULD INHIBIT TEMPERATURES FROM FALLING MUCH FARTHER IN THE EAST...WITH STEADY AND SOME RISING TEMPERATURES WEST. LATEST HI RESOLUTION GUIDANCE HAS BACKED OFF ON THE LIGHT PRECIPITATION DROPPING SOUTH AND EAST ACROSS WESTERN NORTH DAKOTA TONIGHT. HOWEVER WE DO SEE AN AREA OF HIGHER REFLECTIVITIES WHICH COULD RESULT IN SOME LIGHT SNOW REACHING THE GROUND...POISED TO MOVE INTO THE WEST SHORTLY. DID FOLLOW THE TREND OF THE LATEST GUIDANCE BUT WITH A MIX OF PERSISTENCE WHICH STILL KEEPS SOME SLIGHT CHANCE POPS DROPPING SOUTH ACROSS MAINLY WESTERN NORTH DAKOTA TONIGHT. UPDATE ISSUED AT 537 PM CST SAT DEC 19 2015 ...QUICK UPDATE FOR EVENING TEMPERATURES... LATEST SATELLITE AND RADAR IMAGERY SHOWS MOSTLY CLOUDY CONDITIONS ACROSS WESTERN AND CENTRAL NORTH DAKOTA WITH MAINLY MID AND HIGH LEVEL CLOUDS. SURFACE LOW PRESSURE REMAINS OVER SOUTHERN SASKATCHEWAN THROUGH EASTERN MONTANA INTO NORTHEAST WYOMING. ENOUGH BREAKS AND THIN SPOTS IN THE CLOUDS LATE THIS AFTERNOON TO ALLOW TEMPERATURES TO QUICKLY DROP OFF. UPDATED OVERNIGHT LOWS STARTING OUT WITH GRIDDED LAMP GUIDANCE WHICH BETTER DEPICTED THE QUICK DROP EARLY THIS EVENING...THEN TRANSITIONED TO A TIME- LAGGED VERSION OF A CONSENSUS OF SHORT RANGE MODELS...SIMILAR TO THE PREVIOUS FORECAST. ALREADY SEEING TEMPERATURES NEARING OVERNIGHT LOWS OVER CENTRAL ND. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 237 PM CST SAT DEC 19 2015 FOG POTENTIAL AND LIGHT SNOW TONIGHT HIGHLIGHT THE SHORT TERM FORECAST. THE 12 THROUGH 19 UTC HRRR ITERATIONS HAVE BEEN VERY CONSISTENT IN SUGGESTING THE POTENTIAL FOR FOG TONIGHT INTO SUNDAY MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA. FOG IS FIST EXPECTED TO FORM ACROSS THE JAMES RIVER VALLEY LATE THIS EVENING WITH INCREASING LOW LEVEL MOISTURE OVER THE SNOWPACK VIA SOUTHEASTERLY WINDS...AND PLUME WESTWARD TOWARDS THE HIGHWAY 83 CORRIDOR. ACROSS THE WEST...BEHIND A WEAK COLD FRONT TONIGHT...STRATUS BUILD DOWN TO FOG IS ALSO SUGGESTED BY THE HRRR. A SIMILAR SCENARIO IS HINTED AT IN THE 12 AND 18 UTC NAM NEST VISIBILITY FORECASTS. A BAND OF LIGHT SNOW IS ALSO POSSIBLE WITH THE AFOREMENTIONED COLD FRONT TONIGHT INTO EARLY SUNDAY MORNING. ANY SNOWFALL AMOUNTS ARE EXPECTED TO REMAIN AS A DUSTING AT BEST. FOR SUNDAY...A COOLER DAY IS EXPECTED ACROSS THE SOUTHWEST WHERE HIGHS IN 40S ARE OCCURRING THIS AFTERNOON WITH WESTERLY WINDS AND A LACK OF SNOWPACK. ELSEWHERE...THE TEMPERATURE CHANGE BEHIND THE WEAK COLD FRONT WILL BE GENERALLY UNNOTICEABLE ON SUNDAY COMPARED TO SATURDAY HIGHS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 237 PM CST SAT DEC 19 2015 RATHER SEASONABLE LATE DECEMBER TEMPERATURES HIGHLIGHT THE EXTENDED FORECAST...WITH A SOMEWHAT UNCERTAIN PRECIPITATION FORECAST. OVERALL...THE 12 UTC GLOBAL DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT ON THE LARGE SCALE PATTERN OF A BROAD...LOW AMPLITUDE UPPER LEVEL CONUS TROUGH FOR MUCH OF THE PERIOD...POSSIBLY TRANSITIONING TO SPLIT FLOW BY NEXT WEEKEND. THIS WOULD SUGGEST RATHER SEASONABLE TEMPERATURES WITH NO SIGNIFICANT WARM UPS OR COOL DOWNS. HOWEVER...THE RATHER FAST...NEAR ZONAL FLOW AT THE BASE OF THE LOW AMPLITUDE TROUGH DOES INJECT UNCERTAINTY IN THE TIMING OF MULTIPLE WAVES AND ASSOCIATED PRECIPITATION EVENTS THROUGH THE PERIOD. THE BEST AGREEMENT IS ON A WEAK WAVE AND POSSIBLE LIGHT SNOW BAND CENTRAL ON MONDAY. HOWEVER...THEREAFTER THE MODEL SPREAD WIDENS IN REGARDS TO SEVERAL POSSIBLE LIGHT SNOWFALL EVENTS LEADING UP TO CHRISTMAS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1232 AM CST SUN DEC 20 2015 THE LOW CEILINGS HAVE CLEARED KISN BUT EXPECTING MVFR TO POSSIBLY IFR CEILINGS BUILDING IN AGAIN BETWEEN 09Z-13Z. ELSEWHERE...MID AND HIGH CLOUD CIGS AT 06Z BUT HIRES MODELS INDICATE AN AREA OF MVFR-IFR CEILINGS DROPPING SOUTHEAST FROM KMOT TO KBIS FROM 09-13Z AND POSSIBLY EXPANDING BACK WEST INTO KISN AND KDIK. THE HIRES MODELS BRING MVFR VSBYS IN FOG AT KISN/KMOT/KDIK. THE MVFR CIGS ARE EXPECTED TO BECOME VFR BY EARLY TO MID AFTERNOON ON SUNDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JV SHORT TERM...AYD LONG TERM...AYD AVIATION...JV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
331 AM CST SUN DEC 20 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 331 AM CST SUN DEC 20 2015 MAIN FORECAST CONCERNS ARE ON DRIZZLE/FREEZING DRIZZLE POTENTIAL LATE THIS AFTERNOON INTO TONIGHT. A TIGHT PRESSURE GRADIENT WAS IN PLACE ACROSS THE REGION THIS MORNING WITH INCREASING SOUTHERLY FLOW BRINGING WARMER TEMPERATURES INTO THE AREA...AT LEAST WARMER THAN WHAT WE SAW SATURDAY MORNING. EARLY MORNING READINGS RANGE FROM THE LOWER 20S TO UPPER 30S. A WEAK COLD FRONT WAS ADVANCING EASTWARD ACROSS THE DAKOTAS. THIS FRONT WILL MOVE INTO THE UPPER MISSISSIPPI RIVER VALLEY TODAY AND INTERACT WITH A TROUGH LIFTING NORTHEAST OUT OF THE CENTRAL PLAINS...GENERATING SOME DRIZZLE ACROSS PARTS OF THE FORECAST AREA...MAINLY TONIGHT. LATEST FORECAST GUIDANCES HAS REALLY SLOWED THE ARRIVAL OF DRIZZLE AND THIS HAS BEEN INDICATED IN THE LAST THREE MODEL RUNS. ALSO...MODELS ARE TRENDING DRIER ACROSS PORTIONS OF SOUTHEAST MINNESOTA INTO WEST CENTRAL WISCONSIN. WITH THE LATER ONSET TO THE DRIZZLE...FREEZING DRIZZLE POTENTIAL WILL BE LIMITED. HOWEVER...WITH THE RECENT SUBFREEZING TEMPERATURES WOULD EXPECT TO SEE PATCHY FREEZING DRIZZLE WHERE ROAD SURFACES REMAIN BELOW FREEZING...ESPECIALLY AT THE ONSET OF THE DRIZZLE. PORTIONS OF NORTHEAST IOWA AND SOUTHER WISCONSIN WILL HAVE THE BEST CHANCES OF SEEING DRIZZLE AND POSSIBLE LIGHT RAIN LATE TONIGHT INTO MONDAY MORNING. COLDER AIR STARTS TO WRAP INTO THE SYSTEM VERY LATE TONIGHT INTO MONDAY MORNING SO WE WILL THEN MOST LIKELY SEE A SWITCH OVER TO LIGHT SNOW OR FREEZING DRIZZLE BEFORE THE PRECIPITATION ENDS. ANY SNOWFALL OR ICE ACCUMULATIONS WILL BE VERY LIGHT. SATURATION TRIES TO LINGER ACROSS THE AREA INTO MONDAY NIGHT AND WE COULD SEE SOME LIGHT SNOW OR FREEZING DRIZZLE LINGER...BUT CONFIDENCE IS LOW ON THIS OCCURRING. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 331 AM CST SUN DEC 20 2015 WE WILL SEE A BREAK IN PRECIPITATION CHANCES LATE MONDAY NIGHT THROUGH TUESDAY AS WEAK HIGH PRESSURE SLIDES THROUGH. A TROUGH THEN DEVELOPS ACROSS THE CENTRAL CONUS ON TUESDAY INTO TUESDAY NIGHT. THE A SHORTWAVE EJECTS OUT OF THIS TROUGH AND INTO THE FORECAST AREA LATE TUESDAY NIGHT THROUGH WEDNESDAY BRINGING THE NEXT CHANCE OF PRECIPITATION TO THE REGION. WITH INCREASING WARM SOUTHERLY FLOW...MOST OF THE PRECIPITATION WILL BE IN THE FORM OF DRIZZLE TUESDAY NIGHT WITH RAIN EXPECTED ON WEDNESDAY. WE COULD THEN SEE A SWITCH OVER TO SNOW WEDNESDAY NIGHT AS COLDER AIR WRAPS INTO THE BACK SIDE OF THE SYSTEM. A PERSISTENT TROUGH THEN CARVES OUT ACROSS THE WESTERN HALF OF THE CONUS PLACING THE UPPER MISSISSIPPI RIVER VALLEY IN SOUTH/SOUTHWEST FLOW ALOFT. SEVERAL PIECES OF SHORTWAVE ENERGY WILL EJECT OUT OF THIS TROUGH FROM WEDNESDAY NIGHT THROUGH SATURDAY. FORECAST MODELS ARE STRUGGLING TIMING THESE WAVES. A MODELS CONSENSUS BLEND WAS LEANED TOWARDS FOR PRECIPITATION CHANCES DURING THIS TIMEFRAME. AFTER THE FIRST ROUND OF RAIN AND SNOW CHANCES FINALLY EXITS ON THURSDAY...THE NEXT LOOKS TO ARRIVE FRIDAY INTO FRIDAY NIGHT. BEYOND FRIDAY NIGHT THE MODELS REALLY START TO DIVERGE SO FORECAST CONFIDENCE IF VERY LOW GOING INTO NEXT WEEKEND. IT APPEARS TEMPERATURES WILL STAY ON THE WARM SIDE FOR THIS TIME OF YEAR WITH HIGHS IN THE 30S TO LOW 40S WEDNESDAY THROUGH FRIDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1141 PM CST SAT DEC 19 2015 WILL START BOTH SITES WITH WIND SHEAR AND HAVE IT THROUGH THE OVERNIGHT HOURS. THE 20.00Z NAM AND 20.03Z RAP CAME IN WITH STRONGER WINDS ABOVE THE SURFACE AND THE 20.00Z SOUNDING FROM KOAX DID SHOW 45 KNOTS AROUND 2500 FEET SO THE WINDS IN THE MODELS MAY BE PRETTY REASONABLE. THE NAM ALSO CAME IN WITH A SLOWER TREND IN BRINGING IN THE LOW LEVEL MOISTURE FOR THE MVFR/IFR CEILINGS...WHICH THE RAP AGREED WITH...SO PUSHED THESE BACK TO ABOUT THE MIDDLE OF THE AFTERNOON. THE FORECAST SOUNDINGS THEN SHOW THE LOW LEVEL SATURATION DEPTH INCREASING TO AROUND 5000 FEET WITH SOME LIFT THROUGH THIS FROM THE ONGOING ISENTROPIC UP GLIDE FOR THE POSSIBILITY OF DRIZZLE. ADDED IT TO BOTH TAF SITES FOR SUNDAY EVENING...BUT THE NAM AND THE HI-RES MESO MODELS SUGGEST THERE IS THE POSSIBILITY THAT IT COULD MISS KRST. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...WETENKAMP LONG TERM...WETENKAMP AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1141 PM CST SAT DEC 19 2015 .SHORT TERM...(TONIGHT THRU SUNDAY NIGHT) ISSUED AT 225 PM CST SAT DEC 19 2015 MAIN FORECAST CONCERNS THIS PERIOD...DZ/FZDZ/FOG CHANCES SUN AFTERNOON/ NIGHT...TEMPERATURES THRU THE PERIOD. DATA ANALYSIS AT 18Z HAD THE SFC RIDGE AXIS FROM EASTERN MAN TO CENTRAL IL. SUNNY/MOSTLY SUNNY SKIES ACROSS MOST OF THE UPPER MIDWEST UNDER THE SFC RIDGE AXIS AND JUST EAST OF THE MID LEVEL RIDGE AXIS. HOWEVER SOME CIRRUS WERE SLIDING THRU THE UPPER RIDGE AXIS...MAINLY OVER THE NORTH HALF OF THE REGION. WINDS WERE TURNING SOUTH ACROSS MN/IA...BUT EVEN WITH THE SUNNY/MOSTLY SUNNY SKIES MID DAY TEMPS AROUND MUCH OF THE REGION WERE NEAR TO A FEW DEGREES BELOW NORMAL. 19.12Z MODEL RUNS INITIALIZED WELL AND OFFER A TIGHT CONSENSUS OF SOLUTIONS AS MID LEVEL RIDGING MOVES ACROSS THE UPPER MIDWEST TONIGHT. TREND FAVORS SLOWER OF EARLIER RUNS ON THE TROUGH/SHORTWAVE ENERGY MOVING INTO THE CENTRAL/SOUTHERN ROCKIES TONIGHT. THIS SLOWER TREND...FAVORING THE EARLIER ECMWF RUNS...CONTINUES SUNDAY/SUN NIGHT AS THIS TROUGH/ENERGY AND A NORTHERN STREAM WAVE MOVE INTO THE CENTRAL/NORTHERN PLAINS SUN THEN INTO THE REGION SUN NIGHT. EVEN WITH SOME TIMING SHIFT AMONG THE MODELS...THE RATHER TIGHT CONSENSUS KEEPS SHORT-TERM FORECAST CONFIDENCE GOOD THIS CYCLE. FOR THE SHORT TERM...LOW LEVEL WARM ADVECTION STRENGTHENS OVER THE REGION TONIGHT AHEAD OF THE SFC-850MB LOW/TROUGH MOVING ACROSS THE DAKOTAS. 925MB/850MB TEMPS CLIMB TO NEAR/ABOVE 0C ACROSS THE AREA BY 12Z. LOWS STILL EXPECTED TO BE THIS EVENING. THIS AS SOUTH/SOUTHEAST WINDS FOR BOUNDARY LAYER MIXING INCREASE...HIGH CLOUDS THICKEN OVER THE AREA LATER TONIGHT AND THE WARM ADVECTION PRODUCE STEADY/SLOWLY RISING TEMPS AFTER MIDNIGHT. LOWER LEVEL MOISTURE INCREASE...SFC TO ABOUT 800MB...STILL ON TRACK TO ARRIVE VERY LATE TONIGHT AND MORESO SUN MORNING. INITIAL MOISTURE LATE TONIGHT/SUN MORNING GENERALLY BELOW 900MB...ONLY ABOUT 1KM DEEP. THIS AND THE SLOWING OF THE MID LEVEL TROUGH/SHORTWAVE...LEFT FORECAST GRIDS DRY THRU 18Z SUN. DEPTH OF MOISTURE INCREASE TO 1.5 TO 2KM SUN AFTERNOON AS 925-850MB WARM ADVECTION AHEAD OF THE LOW LEVEL TROUGH AXIS REMAINS OVER THE AREA. TOP OF THE MOISTURE COLUMN ONLY 0C TO -4C...TOO WARM FOR ICE IN THE CLOUDS. DEPTH OF THE MOISTURE AND AN INVERSION ABOVE IT...PRECIPITATION TYPE SUN AFTERNOON THRU SUN EVENING CONTINUES TO TREND AS -DZ. BOUNDARY LAYER TEMPS BY SUN AFTERNOON AND FOR SUN EVENING LOOKING TO MOSTLY BE IN THE MID 30S TO AROUND 40. HOWEVER RECENT COLD TEMPS HAVE PRODUCED A FEW INCHES OF GROUND FROST AND ROAD SFC TEMPS THAT ARE BELOW FREEZING. THESE SURFACES WILL NOT WARM UP/THAW AS FAST AS THE BOUNDARY LAYER TEMPS WARM ABOVE 32F. THIS LEAVES THE POTENTIAL FOR SOME -FZDZ ON UNTREATED/SHADED ROAD SURFACES/COLD SIDEWALKS UNTIL THEY WARM ABOVE 32F. CONTINUED A MENTION OF -FZDZ IN THE GRIDS SUN AFTERNOON/EVENING MAINLY OVER THE NORTH HALF OF THE FORECAST AREA WHERE BOUNDARY LAYER TEMPS WILL BE COOLER AND THE COLD GROUND SLOWER TO WARM UP. WITH THE INCREASING BOUNDARY LAYER MOISTURE OVER THE COLD GROUND...CONTINUED THE PATCHY FOG MENTION LATE SUN AFTERNOON AND MUCH OF SUN NIGHT. SIGNAL IS STILL THERE FOR SOME DEEPER MOISTURE ASSOCIATED WITH THE 700MB TROUGH TO MOVE IN AFTER MIDNIGHT SUN NIGHT. ENOUGH SO FOR CLOUD TOP TEMPS IN THE -10C TO -15C RANGE FOR A PERIOD OF ICE IN THE CLOUDS. INCLUDED -SN IN THE PRECIPITATION MIX BETWEEN ROUGHLY 09Z-15Z MON. BY THIS TIME THOUGH...FORCING/LIFT IS EXITING AND ANY -SN AMOUNTS WOULD BE MINIMAL. USED A BLEND OF THE GUIDANCE LOWS TONIGHT/SUN NIGHT. WITH THICKENING LOW CLOUDS SUN... LEANED TOWARD COOLER OF THE GUIDANCE HIGHS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 225 PM CST SAT DEC 19 2015 FOR MONDAY THRU TUESDAY NIGHT... MAIN FORECAST CONCERNS THIS PERIOD...LINGERING WINTRY MIX MON MORNING... -RA/-SN CHANCES TUE NIGHT...ABOVE NORMAL TEMPERATURES. GOOD CONSISTENCY AMONG 19.12Z MODELS FOR THE MID LEVEL TROUGH AXIS TO MOVE QUICKLY EAST OF THE AREA MON MORNING...WITH WEAK SHORTWAVE RIDGING FOR THE MON AFTERNOON. TIGHTER SIGNAL FOR ANOTHER SHORTWAVE TO MOVE ACROSS THE MON NIGHT...THEN SOUTHWEST FLOW TO DEVELOP OVER THE REGION TUE/TUE NIGHT AHEAD OF THE ENERGY COMING THRU THE NORTHERN ROCKIES AND CARVING OUT A MODEST TROUGH OVER THE CENTRAL/ NORTHERN PLAINS BY 12Z WED. WITH DECENT MODEL AGREEMENT ON THE DETAILS...FORECAST CONFIDENCE FOR MON THRU TUE NIGHT IS GENERALLY GOOD THIS CYCLE. MIXED PRECIPITATION CHANCES COMING OUT OF SUN NIGHT LINGER OVER THE EAST HALF OF THE FORECAST AREA MON MORNING...AND MAINLY IN THE 12-15Z PERIOD. SOME DEEPER LAYERED SUBSIDENCE TO MOVE ACROSS THE AREA WITH THE SFC- MID LEVEL RIDGE AXIS. HOWEVER...PLENTY OF LOWER LEVEL MOISTURE LOOKS TO REMAIN OVER THE AREA MON/MON NIGHT...TRAPPED UNDER THE STRENGTHENING SUBSIDENCE INVERSION. DID ADD A PERIOD OF PARTLY SUNNY SKIES MON AFTERNOON...MAINLY TO BLEND WITH NEIGHBORING GRIDS. HOWEVER IT LOOKS LIKE WE MAY NOT SEE MUCH IN THE WAY OF SUNSHINE AGAIN UNTIL PERHAPS TUE AFTERNOON IN THE INCREASING SOUTH/SOUTHWEST FLOW TO ADVECT THE TRAPPED MOISTURE NORTH/EAST OF THE AREA. SHORTWAVE COMING ACROSS MON NIGHT PROVIDES SOME MID LEVEL ALONG WITH A RETURN OF SOME 925-850MB WARM ADVECTION. THIS WHILE MODEL SOUNDINGS/X-SECTIONS SHOW MINIMAL MOISTURE/SATURATION IN THE 900- 500MB LAYER ABOVE THE TRAPPED SFC- 900MB MOISTURE. LEFT GRIDS DRY MON NIGHT AS THE WAVE WOULD PASS. STRONGER LOW LEVEL WARM ADVECTION RETURNS TUE...WITH 925-850MB TEMPS BACK ABOVE 0C OVER THE FORECAST AREA BY 00Z WED. APPEARS IF LOWER CLOUDS ARE IN FACT ADVECTED OUT TUE...MID/HIGH MOISTURE/CLOUDS AHEAD OF THE NEXT TROUGH INTO THE PLAINS WOULD KEEP SKIES MOSTLY CLOUDY/CLOUDY. IF WE DO IN FACT GET A PERIOD OF SUNSHINE TUE...HIGHS IN THE FORECAST GRIDS FOR TUE MAY BE A FEW DEGREES TOO COOL. DEEP SATURATION FOR A PRECIPITATION CHANCE TUE NIGHT LOOKING TO BE A PROBLEM...MUCH LIKE SUN AFTERNOON/NIGHT IS. ANY SMALL TUE NIGHT PRECIPITATION CHANCE MAY BE MORE -DZ. LEFT THIS AS -RA/-SN FOR NOW BUT DID TREND IT STRONGLY TOWARD MAINLY -RA WITH THE 925- 850MB TEMPS NEAR/ABOVE 0C TUE NIGHT. USED A BLEND OF THE GUIDANCE HIGHS/LOWS FOR MON THRU TUE. WITH SNOW-FREE GROUND...THICKENING CLOUDS AND SOUTH-SOUTHEAST WINDS FOR BOUNDARY LAYER MIXING...FAVORED WARMER OF GUIDANCE LOWS TUE NIGHT. FOR WEDNESDAY THRU SATURDAY...DAYS 4 TO 7... MAIN FORECAST CONCERNS THIS PERIOD...SMALL RAIN/SNOW CHANCES MOST OF THE PERIOD...ABOVE NORMAL TEMPERATURES. MEDIUM RANGE MODEL RUNS OF 19.00Z/19.12Z IN RATHER GOOD AGREEMENT WITH THE LARGE-SCALE FEATURES ACROSS NOAM WED...NAMELY LONGWAVE TROUGHING OVER THE CENTRAL/WESTERN CONUS. BUT...PLENTY OF DETAIL DIFFERENCES ON THE SHORTWAVE ENERGY RIPPLING THRU THIS TROUGH AND INTO THE UPPER MIDWEST WED/WED NIGHT. THE LARGE-SCALE CONSISTENCY REMAINS REASONABLE THU THRU SAT AS THE TROUGH FROM WED LIFTS INTO THE CAN MARITIMES AND ANOTHER STRONG TROUGH DIGS INTO THE CENTRAL/SOUTHERN ROCKIES. HOWEVER...LIKE WED THERE ARE PLENTY OF DETAIL DIFFERENCES ON THE SHORTWAVE ENERGY RIPPLING THRU THE GENERALLY PROGRESSIVE LONGWAVE FLOW. FORECAST CONFIDENCE FOR TUE THRU SAT IS BELOW AVERAGE THIS CYCLE. THIS PERIOD STARTS OUT WITH VARIOUS PIECES OF SHORTWAVE ENERGY IN THE CENTRAL CONUS TROUGH PROGGED TO LIFT TOWARD/ACROSS THE REGION WED/WED NIGHT. THE ATTENDANT SFC-850MB LOW WOULD GENERALLY PASS ACROSS NORTHERN MN INTO ONT WITH THE FORECAST AREA ON THE WARM SIDE OF THE SYSTEM. BULK OF THE LOWER LEVEL THERMO-DYNAMIC FORCING WOULD PASS WEST/NORTH OF THE FORECAST AREA AS WELL. LOWER LEVEL THERMAL PROFILE INDICATE ANY PRECIPITATION WED/WED EVENING MAINLY AS -RA/-DZ...WITH SOME -SN POSSIBLE LATER WED NIGHT/THU MORNING AS COLDER AIR WOULD WRAP IN BEHIND THE DEPARTING SYSTEM. THU WOULD SEE THE MID LEVEL TROUGH AXIS EXIT EAST...WITH RISING HGTS OVER THE REGION AHEAD OF THE NEXT STRONG TROUGH DIGGING INTO THE ROCKIES. CONSENSUS WOULD DRIFT A WEAK RIDGE OF HIGH PRESSURE ACROSS THE REGION LATER THU INTO FRI MORNING...FOR A DRY PERIOD. ECMWF EJECTS A STRONGER PIECE OF ENERGY OUT OF THE WESTERN TROUGH AND INTO THE UPPER MIDWEST ON CHRISTMAS DAY...WHILE GFS HAS BROAD RIDGING ALOFT AND SFC HIGH PRESSURE OVER THE REGION. STRONGER ECMWF SOLUTION FOR FRI IS ALSO A WARMER SOLUTION...WITH ANY OF ITS PRECIPITATION CHANCES FRI AFTERNOON/NIGHT MAINLY AS RAIN. THE TIMING DIFFERENCES KEEP THE MODELS AT ODDS SAT...AND A LOT VARIABILITY SEEN AMONG ENSEMBLE MEMBERS AT DAYS 6/7. UNTIL THE DETAILS SORT THEMSELVES OUT...THE SMALL CONSENSUS PRECIPITATION CHANCES FRI- SAT OKAY FOR NOW. MODEL/ENSEMBLE CONSENSUS OF HIGHS/LOWS RUNNING 5F TO 10F ABOVE NORMAL IN THE DAY 4-7 PERIOD LOOK GOOD WITH THE CAN/ARCTIC AIR REMAINING BOTTLED UP WELL NORTH IN CANADA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1141 PM CST SAT DEC 19 2015 WILL START BOTH SITES WITH WIND SHEAR AND HAVE IT THROUGH THE OVERNIGHT HOURS. THE 20.00Z NAM AND 20.03Z RAP CAME IN WITH STRONGER WINDS ABOVE THE SURFACE AND THE 20.00Z SOUNDING FROM KOAX DID SHOW 45 KNOTS AROUND 2500 FEET SO THE WINDS IN THE MODELS MAY BE PRETTY REASONABLE. THE NAM ALSO CAME IN WITH A SLOWER TREND IN BRINGING IN THE LOW LEVEL MOISTURE FOR THE MVFR/IFR CEILINGS...WHICH THE RAP AGREED WITH...SO PUSHED THESE BACK TO ABOUT THE MIDDLE OF THE AFTERNOON. THE FORECAST SOUNDINGS THEN SHOW THE LOW LEVEL SATURATION DEPTH INCREASING TO AROUND 5000 FEET WITH SOME LIFT THROUGH THIS FROM THE ONGOING ISENTROPIC UP GLIDE FOR THE POSSIBILITY OF DRIZZLE. ADDED IT TO BOTH TAF SITES FOR SUNDAY EVENING...BUT THE NAM AND THE HI-RES MESO MODELS SUGGEST THERE IS THE POSSIBILITY THAT IT COULD MISS KRST. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RRS LONG TERM....RRS AVIATION...04
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
518 AM MST SUN DEC 20 2015 .UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS... && .SYNOPSIS... A WEAK FRONTAL BOUNDARY WILL BRING SLIGHTLY COOLER CONDITIONS TO THE AREA TODAY. THERE IS ALSO A SLIGHT CHANCE OF SHOWERS ACROSS NORTHERN MARICOPA AND GILA COUNTIES. PACIFIC MOISTURE WILL SPREAD ACROSS THE REGION THROUGH THE WEEK RESULTING IN PERIODS OF CLOUDINESS AND A SLIGHT CHANCE OF PRECIPITATION...MAINLY NORTH AND EAST OF PHOENIX. TEMPERATURES WILL REMAIN NEAR NORMAL BUT ARE EXPECTED TO DROP LATE IN THE WEEK AND INTO THE WEEKEND AS A LOW PRESSURE SYSTEM AFFECTS THE DESERT SOUTHWEST. && .DISCUSSION... WV IMAGERY SHOWS A WELL-DEFINED VORT MAX MOVING STEADILY EASTWARD THROUGH THE MOJAVE DESERT. AT THE SURFACE...A WEAK COLD FRONT EXTENDS FROM AN AREA OF LOW PRESSURE ACROSS THE SOUTHERN ROCKIES INTO THE LOWER CO RIVER VALLEY. A FEW SHOWERS ALONG THE FRONT HAVE BEEN OBSERVED NEAR EL CENTRO...WHICH AMOUNTED TO A TRACE. LATEST HRRR SUGGESTS THIS LINE WILL WEAKEN AS IT HEADS EAST INTO AZ...THOUGH RUNS OF THE LOCAL WRF SUGGEST SOME REDEVELOPMENT OF ISOLATED SHOWERS ACROSS THE HIGHER TERRAIN OF MARICOPA AND GILA COUNTIES LATER THIS MORNING. OTHERWISE...TEMPERATURES WILL BE A FEW DEGREES COOLER TODAY BEHIND THE TROUGH...WITH HIGHS GENERALLY IN THE LOWER 60S ACROSS THE LOWER DESERTS. MODELS REMAIN IN GOOD AGREEMENT EARLY THIS WEEK...INDICATING A STRONG ATMOSPHERIC RIVER WILL DEVELOP AROUND AN ANTICYCLONE IN THE CENTRAL PACIFIC. RESULTING NORTHWESTERLY FLOW WILL RESULT IN PERIODS OF MID AND HIGH CLOUDS ALONG WITH A GRADUAL WARMING TREND THROUGH THURSDAY. BRUNT OF THE PRECIPITATION WILL BE WELL TO OUR NORTH...ALONG THE WEST COAST AND ACROSS THE INTERMOUNTAIN WEST. HOWEVER...LATEST OPERATIONAL GFS/ECMWF SUGGEST THAT SUFFICIENT MOISTURE TRANSPORT WILL COINCIDE WITH OCCASIONAL ASCENT TO SUPPORT ISOLATED SHOWER ACTIVITY ACROSS THE HIGHER TERRAIN...MAINLY NORTHEAST OF PHOENIX THROUGH THURSDAY. IT IS DIFFICULT TO PINPOINT EXACTLY WHEN THE BEST CHANCE OF PRECIPITATION WILL OCCUR...THOUGH THE MODEL CONSENSUS IS THAT ANY RAIN THAT DOES DEVELOP WILL BE QUITE LIGHT. MODELS ARE EXHIBITING CONSIDERABLE MORE SPREAD WITH REGARD TO THE EVOLUTION OF A TROUGH LATE IN THE WEEK. THE TROUGH IS EXPECTED TO DROP SOUTHWARD OUT OF THE GULF OF ALASKA AND TOWARDS THE DESERT SOUTHWEST. HOWEVER...RECENT TRENDS IN THE NAEFS...GEFS AND ECMWF ENSEMBLE MEANS SUGGEST LESS OF AN IMPACT ACROSS THE AREA. ALL ENSEMBLE MEANS ALONG WITH THE OPERATIONAL ECMWF DEPICT AN OPEN WAVE PASSING BY TO OUR NORTH AND EAST. LATEST 00Z OPERATIONAL GFS IS CONSIDERABLY STRONGER AND FURTHER WEST...THOUGH IT APPEARS TO BE AN OUTLIER WHEN COMPARED TO ITS ENSEMBLES. NORMALIZED SPREAD AMONG THE ECMWF ENSEMBLE MEMBERS IS ALIGNED WITH THE TROUGH AXIS...SUGGESTING THAT THE UNCERTAINTY IS MORE WITH MAGNITUDE OF THE SYSTEM AND LESS WITH THE POSITIONING AND TIMING. FORECAST POPS HAVE BEEN LOWERED SOMEWHAT FOR CHRISTMAS DAY THROUGH SATURDAY. HOWEVER...A SLIGHT CHANCE REMAINS...OWING TO THE PREPONDERANCE OF PREVIOUS RUNS THAT SUGGESTED A DEEPER AND LESS PROGRESSIVE SYSTEM. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... UPPER LEVEL TROUGH QUICKLY MOVING THROUGH ARIZONA THIS MORNING WILL BRING ISOLATED LIGHT RAIN SHOWERS TO HIGHER TERRAIN AREAS NORTH AND EAST OF PHOENIX THROUGH 18Z. A CLOUD BAND WITH BKN DECKS DOWN TO 6K FEET AT TIME SHOULD ALSO AFFECT THE PHOENIX AREA THROUGH MID MORNING BEFORE BECOMING MORE SCATTERED IN NATURE THROUGH THE REST OF THE AFTERNOON HOURS. EVENTUALLY CLOUDS WILL LIFT WITH JUST HIGH CLOUDS REMAINING FOR THE REST OF TONIGHT. WINDS ACROSS THE PHOENIX AREA WILL REMAIN LESS THAN 10 KTS AND GENERALLY FOLLOW TYPICAL DIURNAL DIRECTIONAL PATTERNS WHILE INITIAL BREEZY CONDITIONS ACROSS SOUTHEAST CALIFORNIA WILL TURN TO LIGHTER WINDS STARTING THIS AFTERNOON. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... TUESDAY THROUGH SATURDAY... DRY NORTHWEST FLOW ALOFT WILL DOMINATE INTO THE MIDDLE PART OF THE WEEK BEFORE INCREASING MOISTURE SLOWLY BEGINS TO AFFECT THE REGION. THIS MOISTURE WILL EVENTUALLY ALLOW FOR RAIN/SNOW CHANCES BEGINNING WEDNESDAY OR THURSDAY WITH A STRONG PACIFIC LOW PRESSURE TROUGH AIDING IN BETTER PRECIPITATION CHANCES ON THURSDAY AND FRIDAY. TEMPERATURES WILL START OUT NEAR NORMALS...BUT WITH THE TROUGH DIGGING IN LATE NEXT WEEK TEMPERATURES WILL DIP TO WELL BELOW NORMAL READINGS STARTING FRIDAY. WINDS THROUGH WEDNESDAY WILL REMAIN ON THE LIGHT SIDE WITH SOME BREEZY TO GUSTY WINDS AT TIMES ON THURSDAY AND FRIDAY. POTENTIAL FOR STRONG WINDS WITH GUSTS APPROACHING 40 MPH ARE POSSIBLE ON SATURDAY...MAINLY AFFECTING THE LOWER COLORADO RIVER VALLEY. MINIMUM RELATIVE HUMIDITIES WILL BE ON THE HIGHER SIDE THROUGH MUCH OF THE PERIOD MOSTLY FALLING IN A 25-40 PERCENT RANGE...BUT DRIER AIR WORKING FROM THE NORTHWEST FRIDAY NIGHT AND SATURDAY WILL ALLOW FOR HUMIDITIES TO DROP INTO THE TEENS. && .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING PROCEDURES. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...HIRSCH AVIATION...KUHLMAN FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
338 AM MST SUN DEC 20 2015 .SYNOPSIS... A WEAK FRONTAL BOUNDARY WILL BRING SLIGHTLY COOLER CONDITIONS TO THE AREA TODAY. THERE IS ALSO A SLIGHT CHANCE OF SHOWERS ACROSS NORTHERN MARICOPA AND GILA COUNTIES. PACIFIC MOISTURE WILL SPREAD ACROSS THE REGION THROUGH THE WEEK RESULTING IN PERIODS OF CLOUDINESS AND A SLIGHT CHANCE OF PRECIPITATION...MAINLY NORTH AND EAST OF PHOENIX. TEMPERATURES WILL REMAIN NEAR NORMAL BUT ARE EXPECTED TO DROP LATE IN THE WEEK AND INTO THE WEEKEND AS A LOW PRESSURE SYSTEM AFFECTS THE DESERT SOUTHWEST. && .DISCUSSION... WV IMAGERY SHOWS A WELL-DEFINED VORT MAX MOVING STEADILY EASTWARD THROUGH THE MOJAVE DESERT. AT THE SURFACE...A WEAK COLD FRONT EXTENDS FROM AN AREA OF LOW PRESSURE ACROSS THE SOUTHERN ROCKIES INTO THE LOWER CO RIVER VALLEY. A FEW SHOWERS ALONG THE FRONT HAVE BEEN OBSERVED NEAR EL CENTRO...WHICH AMOUNTED TO A TRACE. LATEST HRRR SUGGESTS THIS LINE WILL WEAKEN AS IT HEADS EAST INTO AZ...THOUGH RUNS OF THE LOCAL WRF SUGGEST SOME REDEVELOPMENT OF ISOLATED SHOWERS ACROSS THE HIGHER TERRAIN OF MARICOPA AND GILA COUNTIES LATER THIS MORNING. OTHERWISE...TEMPERATURES WILL BE A FEW DEGREES COOLER TODAY BEHIND THE TROUGH...WITH HIGHS GENERALLY IN THE LOWER 60S ACROSS THE LOWER DESERTS. MODELS REMAIN IN GOOD AGREEMENT EARLY THIS WEEK...INDICATING A STRONG ATMOSPHERIC RIVER WILL DEVELOP AROUND AN ANTICYCLONE IN THE CENTRAL PACIFIC. RESULTING NORTHWESTERLY FLOW WILL RESULT IN PERIODS OF MID AND HIGH CLOUDS ALONG WITH A GRADUAL WARMING TREND THROUGH THURSDAY. BRUNT OF THE PRECIPITATION WILL BE WELL TO OUR NORTH...ALONG THE WEST COAST AND ACROSS THE INTERMOUNTAIN WEST. HOWEVER...LATEST OPERATIONAL GFS/ECMWF SUGGEST THAT SUFFICIENT MOISTURE TRANSPORT WILL COINCIDE WITH OCCASIONAL ASCENT TO SUPPORT ISOLATED SHOWER ACTIVITY ACROSS THE HIGHER TERRAIN...MAINLY NORTHEAST OF PHOENIX THROUGH THURSDAY. IT IS DIFFICULT TO PINPOINT EXACTLY WHEN THE BEST CHANCE OF PRECIPITATION WILL OCCUR...THOUGH THE MODEL CONSENSUS IS THAT ANY RAIN THAT DOES DEVELOP WILL BE QUITE LIGHT. MODELS ARE EXHIBITING CONSIDERABLE MORE SPREAD WITH REGARD TO THE EVOLUTION OF A TROUGH LATE IN THE WEEK. THE TROUGH IS EXPECTED TO DROP SOUTHWARD OUT OF THE GULF OF ALASKA AND TOWARDS THE DESERT SOUTHWEST. HOWEVER...RECENT TRENDS IN THE NAEFS...GEFS AND ECMWF ENSEMBLE MEANS SUGGEST LESS OF AN IMPACT ACROSS THE AREA. ALL ENSEMBLE MEANS ALONG WITH THE OPERATIONAL ECMWF DEPICT AN OPEN WAVE PASSING BY TO OUR NORTH AND EAST. LATEST 00Z OPERATIONAL GFS IS CONSIDERABLY STRONGER AND FURTHER WEST...THOUGH IT APPEARS TO BE AN OUTLIER WHEN COMPARED TO ITS ENSEMBLES. NORMALIZED SPREAD AMONG THE ECMWF ENSEMBLE MEMBERS IS ALIGNED WITH THE TROUGH AXIS...SUGGESTING THAT THE UNCERTAINTY IS MORE WITH MAGNITUDE OF THE SYSTEM AND LESS WITH THE POSITIONING AND TIMING. FORECAST POPS HAVE BEEN LOWERED SOMEWHAT FOR CHRISTMAS DAY THROUGH SATURDAY. HOWEVER...A SLIGHT CHANCE REMAINS...OWING TO THE PREPONDERANCE OF PREVIOUS RUNS THAT SUGGESTED A DEEPER AND LESS PROGRESSIVE SYSTEM. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... CLOUD BAND ASSOCIATED WITH APPROACHING COLD FRONT AS OF 04Z EXTENDS FROM NORTHEAST NEVADA SOUTH-SOUTHWESTWARD TO NEAR KSAN. ANTICIPATE SOME BREAKUP OF THE CLOUD BAND AS IT MOVES OVER THE SOUTHERN CALIFORNIA MOUNTAINS INTO THE DESERTS TONIGHT. HOWEVER...EXPECT AT LEAST SOME SCATTERED CUMULUS AT FL050-070 REACHING LOWER COLORADO RIVER VALLEY BY 07Z-09Z AND PHOENIX AREA BY 10Z-12Z. ANTICIPATE A GOOD POSSIBILITY OF THE CUMULUS BEING BKN-OVC AT TIMES EAST OF THE LOWER COLORADO RIVER VALLEY...INCLUDING METRO PHOENIX. SOME SPOTTY LIGHT SHOWERS/SPRINKLES ARE ALSO POSSIBLE. EXPECT SOUTHWEST AND WEST SURFACE WINDS NEAR AND EAST OF THE LOWER COLORADO RIVER VALLEY TO CONTINUE OVERNIGHT AND WELL INTO THE DAY SUNDAY. OVER PHOENIX AREA...SURFACE WINDS WILL REMAIN LIGHT AND FAVOR THE SOUTHEAST QUADRANT THROUGH AT LEAST 15Z BEFORE TRENDING TO SOUTHWEST BY 17-19Z. STRONG SOUTHWEST AND WEST WINDS ALOFT CAN BE EXPECTED OVERNIGHT AND THROUGH THE DAY SUNDAY. ANTICIPATE THAT WE WILL REMAIN BELOW LLWS CRITERIA THOUGH. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... MONDAY THROUGH FRIDAY... DRY NORTHWEST FLOW ALOFT WILL DOMINATE THROUGH THE MIDDLE OF NEXT WEEK BEFORE A STRONG PACIFIC LOW PRESSURE TROUGH APPROACHES THE REGION FOR LATE IN THE WEEK. THIS TROUGH WILL BRING INCREASING MOISTURE AND A CHANCE OF PRECIPITATION STARTING THURSDAY. BEST CHANCES FOR WETTING RAIN/SNOW WILL LIKELY FALL ON FRIDAY. TEMPERATURES WILL END UP AROUND NORMAL READINGS THROUGH THURSDAY BUT WITH THE TROUGH DIGGING IN LATE NEXT WEEK TEMPERATURES WILL DIP TO WELL BELOW NORMAL READINGS FOR FRIDAY. WINDS THROUGH WEDNESDAY WILL REMAIN ON THE LIGHT SIDE WITH SOME BREEZY TO GUSTY WINDS AT TIMES ON THURSDAY AND FRIDAY. MINIMUM RELATIVE HUMIDITIES WILL BE ON THE HIGHER SIDE AND MOSTLY FALL IN A 25-40 PERCENT RANGE. && .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING PROCEDURES. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...HIRSCH AVIATION...AJ FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
845 AM MST SUN DEC 20 2015 .UPDATE... ISSUED AT 825 AM MST SUN DEC 20 2015 LATEST HRRR SHOWING GREATER AREAS COVERAGE FOR PCPN/QPF THIS AFTN ACROSS THE NORTHEAST PLAINS. AS A RESULT...A INCREASED THE MENTION OF SLIGHT CHANCE 10-20 PERCENT COVERAGE...GENERALLY FM AROUND DENVER/BOULDER EAST AND SOUTH AFTER 20Z. RUC13 SOUNDINGS SHOW DECENT MOISTURE TO GO WITH SOME FVBL INSTBY WITH THE PASSAGE OF THE TROUGH THIS AFTN...SO DOWNSLOPE/DCRG QG ASCENT MAY REDUCE THE POPS ACROSS THE FOOTHILLS AND ADJACENT PLAINS BUT WILL NOT NEGATE IT ALTOGETHER. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 310 AM MST SUN DEC 20 2015 WATER VAPOR IMAGERY SHOWING ELONGATED TROF MOVING EAST OVER GREAT BASIN EARLY THIS AM WITH A CIRCULATION CENTER OVER FAR SOUTHERN NEVADA. THIS TROF WILL MOVE ACROSS COLORADO DURING THIS AFTERNOON. THERE IS STILL A FAIR AMOUNT OF MID AND HIGH LEVEL MOISTURE AHEAD OF THIS FEATURE WITH MOST OF THE BETTER MOISTURE ASSOCIATED WITH THE LOW OVER SOUTHERN NEVADA AND WESTERN UTAH. THIS BETTER MOISTURE WILL MOVE INTO THE MOUNTAINS THIS AFTERNOON. OVERALL THIS SYSTEM NOT LOOKING VERY IMPRESSIVE BUT THERE IS MODEST AMOUNTS OF QG UPWARD FORCING THIS AFTERNOON. OVERALL MOISTURE DOES APPEAR TO BE LACKING WITH THIS SYSTEM DESPITE DECENT QG NUMBERS. LAPSE RATES DO STEEPEN LATER IN THE DAY WHICH WILL HELP SOME IN PRECIP POTENTIAL. OVERALL SNOWFALL IN THE MOUNTAINS LOOKS TO BE LIGHT WITH GENERALLY 1-3 INCH ACCUMULATION AS OROGRAPHIC FLOW IMPROVES DURING THE AFTERNOON. FOR TONIGHT IN THE MOUNTAINS...MOISTURE BECOMES MORE SHALLOW WHILE WARM ADVECTION DEVELOPS AT MOUNTAIN TOP. STILL GOOD OROGRAPHIC FLOW DESPITE LAPSE RATES SO COULD STILL SEE A FEW MORE INCHES OF SNOW IN THE MOUNTAINS. GUSTY WINDS AT TIMES AS WELL WITH THE STRONG WESTERLY FLOW. DOSEN`T LOOK LIKE HIGH WINDS BUT CERTAINLY SOME GUSTS IN THE 30-50 MPH RANGE. ACROSS NORTHEAST COLORADO A WEAK ASSOCIATED COLD FRONT WILL MOVE SOUTHWARD LATER THIS MORNING AS WINDS SHIFT NORTHERLY. MODELS ARE HINTING AT SOME LIGHT SHOWERS DEVELOPING OVER THE PALMER DIVIDE AND FAR EASTERN PLAINS SO WILL ADD SOME LOW POPS IN THOSE AREAS. TEMPERATURES WILL BE A BIT COOLER ON THE PLAINS FOLLOWING THE FRONTAL PASSAGE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 310 AM MST SUN DEC 20 2015 A SHORTWAVE TROUGH WILL PASS OVER THE AREA MONDAY MORNING FOR AN INCREASE IN SNOWFALL OVER THE MOUNTAINS. STRONG AND GUSTY WINDS TO 50 MPH WILL CAUSE VISIBILITY ISSUES ALONG THE HIGHER PASSES IN BLOWING SNOW. SLIGHT RIDGING WILL SLOW SNOWFALL THROUGH THE REST OF THE DAY AND EVENING. IT WILL REMAIN DRY OVER THE PLAINS WITH SLIGHTLY COOLER TEMPERATURES FROM THE PASSING SHORTWAVE. LATE MONDAY NIGHT INTO TUESDAY...A STRONG PACIFIC JET ORIENTED ALONG THE NORTHWEST FLOW WILL PUSH INTO THE GREAT BASIN PUSHING MORE MOISTURE INTO THE COLORADO MOUNTAINS. THE JET WILL MOVE OVER THE STATE TUESDAY AND WEDNESDAY BEFORE TURNING MORE WESTERLY THEN SOUTHWESTERLY ACROSS THE SOUTHERN PART OF THE STATE THROUGH THE REST OF THE WEEK. THIS WILL BRING AN EXTENDED PERIOD OF SNOW ACROSS THE MOUNTAINS. OROGRAPHIC SNOW IS EXPECTED TO RAMP UP ESPECIALLY AFTER MIDNIGHT....WITH 2 TO 5 INCHES FALLING BY TUESDAY MORNING. WINDS WILL BE INCREASING AS WELL AS A SURFACE LOW DEEPENS OVER THE LEE OF THE ROCKIES. SNOW IS EXPECTED TO CONTINUE FALLING OVER THE MOUNTAINS THROUGH WEDNESDAY EVENING AT LEAST. WITH THE EXTENDED TIME OF SNOWFALL AND WINDS...A HIGHLIGHT MAY NEED TO BE ISSUED TO DEAL WITH THE IMPACTS ON TRAVEL AND SAFETY. THE PLAINS MAY SEE A SNOW SHOWER OR TWO MOVE EAST FROM THE FOOTHILLS TUESDAY NIGHT AS AS UPPER TROUGH PASSES OVERHEAD. A LONGWAVE UPPER TROUGH WILL DIG OVER THE GREAT BASIN THURSDAY. MODELS ARE HAVING A HARD TIME COMING TO A CONSENSUS ON WHAT THE FEATURE WILL END UP DOING AFTER THIS. THE FEATURE MAY EITHER DIG SOUTH INTO NORTHERN MEXICO AS A CUTOFF LOW BY SATURDAY LIKE THE GFS SHOWS...OR PASS OVER THE STATE FRIDAY THEN BECOME A CLOSED LOW OVER KANSAS BY SATURDAY MORNING BEFORE PUSHING NORTHEAST INTO THE GREAT LAKES REGION BY SUNDAY. EITHER WAY...BOTH MODELS HINTING AT PRECIP PUSHING NORTH INTO THE STATE THURSDAY EVENING THEN EITHER HEADING BACK SOUTH LIKE THE GFS SHOWS OR PUSHING EAST INTO A NICE GREAT PLAINS STORM LIKE THE ECMWF. WILL HAVE A SLIGHT CHANCE OF SNOW FOR THE PLAINS FOR CHRISTMAS EVE AND CHRISTMAS DAY. THE WEEKEND LOOKS TO DRY AND WARM UP AS UPPER RIDGING PUSHES OVER THE STATE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 825 AM MST SUN DEC 20 2015 CONSIDERABLE MID-HIGH LEVEL MOISTURE AHEAD OF WEAK TROF THIS MORNING. AS THE TROF MOVES ACROSS THE AREA DURING THE AFTERNOON COULD BE ISOLATED RAIN/SNOW SHOWERS SO HAVE ADDED VCSH TO THE TAFS. MAY LOWER THE CIGS A BIT MORE AS WELL TO A TEMPO BKN CIGS OF 5-6KFT AGL AFTER 21Z AS WELL IN THE UPCOMING TAFS. E/NE SFC WINDS AT DIA AT THIS TIME WILL TURN NORTHERLY BETWEEN 17-18Z WITH WEAK FRONTAL PASSAGE BUT WINDS SHOULD REMAIN UNDER 15KT WITH FRONT. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...COOPER SHORT TERM...ENTREKIN LONG TERM...KRIEDERMAN AVIATION...COOPER
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
522 AM CST SUN DEC 20 2015 ...Update to aviation forecast discussion... .SHORT TERM...(Today and Tonight) Issued at 257 AM CST SUN DEC 20 2015 Winds already picking up in the early morning hours, with winds aloft forecast to increase and stay up through the day today. This has kept overnight lows up in the 40s most areas. As the boundary layer mixes out this morning, RAP and GFS suggest winds at the top of the mixed layer are close to 50 kts. As a result, expect high temperatures to make it into the middle/upper50s, and wind speeds to gust near wind advisory criteria of 40 kts. Will hoist a wind advisory for those counties along and south of I-70. Still a chance for some light drizzle and light rain to develop late this morning in the WAA regime, followed by precip chances continuing due to the shortwave trof moving eastward out of the high plains later this evening. These showers could also aid in mixing down some of the stronger wind speeds through the day today. Both GFS and NAM indicating just a few hours with some weak instability in the column in the midnight to 3am timeframe as the stronger lift and cold pool aloft move over the eastern part of the state. Have left thunder out at this time given small window, but is worth mentioning here. As trof moves eastward, cooler air moves in behind and lows fall into he 20s to middle 30s. .LONG TERM...(Monday through Saturday) Issued at 257 AM CST SUN DEC 20 2015 On Monday another mid level trough tracks over the central US, which should not have much effect on the overall weather. Highs will be cooler in the mid to upper 40s. On Tuesday return flow quickly develops as yet another shortwave approaches from the west, which will allow temperatures to warm back into the 50s. This shortwave trough appears to deepen Tuesday night as it passes over the forecast area. Increased moisture and lift as well as an advancing cold front could support rain Wednesday morning and into the afternoon. This precip appears to stay confined to portions of eastern KS. Towards the end of the week a few of the models continue to bring out weak shortwaves that could cause light precip, but confidence in timing and location is low at this point. Models continue to show a strong system over the southern Rockies over the weekend, but also continue to struggle on how to evolve that system. && .AVIATION...(For the 12Z TAFS through 12Z Monday Morning) Issued at 521 AM CST SUN DEC 20 2015 Winds have become gusty for the most part this morning and should increase a bit more in the late morning hours. Winds start to diminish in the evening hours before the next wind shift after midnight. Kept light rain late in the period with MVFR cigs. && .TOP Watches/Warnings/Advisories... Wind Advisory until 6 PM CST this evening for KSZ035>040-054>056- 058-059. && $$ SHORT TERM...67 LONG TERM...Sanders AVIATION...67
AREA FORECAST DISCUSSION
NWS GOODLAND KS
348 AM MST SUN DEC 20 2015 .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 157 AM MST SUN DEC 20 2015 THE SHORT TERM PERIOD REMAINS WARMER THAN AVERAGE AND DRY. A WEAK SHORT WAVE TROUGH ALOFT LIFTS OUT ACROSS THE FORECAST AREA EARLY THIS MORNING TO BE FOLLOWED BY A STRONGER SHORT WAVE TROUGH EMBEDDED IN THE UPPER FLOW LATE THIS AFTERNOON AND EARLY EVENING. THIS IS ALL ON THE HEELS OF A COLD FRONT MOVING THROUGH THE FORECAST AREA TODAY...COOLING TEMPERATURES FROM YESTERDAY BY ABOUT 5-10 DEGREES ACROSS MAINLY THE NORTHWEST SECTIONS OF THE FORECAST AREA. THERE IS A POSSIBILITY OF MAINLY THE SOUTHWESTERN SECTIONS SEEING A SPRINKLE OR FLURRY THIS EVENING AS THE SHORT WAVE TROUGH ALOFT MOVES ACROSS THE AREA...BUT DO NOT EXPECT ANY MEASURABLE PRECIPITATION GIVEN THE FAST MOVING NATURE OF THE OPEN WAVE AND THE LIMITED AMOUNT OF MOISTURE IN THE COLUMN. ANOTHER FAST MOVING SHORT WAVE TROUGH ALOFT MOVES ACROSS THE REGION EARLY MONDAY WITH WESTERLY FLOW ALOFT. THE WESTERLY FLOW STARTS TURNING MORE SOUTHWESTERLY AS IT INCREASES AHEAD OF THE NEXT TROUGH THAT WILL BE DEEPENING OVER THE INTERMOUNTAIN REGION ON TUESDAY BEFORE IT MOVES EAST OF THE ROCKIES TUESDAY NIGHT. SURFACE HIGH PRESSURE MOVES ACROSS THE FORECAST AREA ON MONDAY WITH A LEE TROUGH DEEPENING ALONG THE FRONT RANGE MONDAY NIGHT AND EARLY TUESDAY BEFORE MOVING EAST OFF THE FRONT RANGE LATE TUESDAY AFTERNOON AND EVENING JUST AHEAD OF THE UPPER TROUGH. THERE APPEARS TO BE A POSSIBILITY OF SOME VERY LIGHT PRECIPITATION WITH THE TROUGH TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. THE GFS FAVORS A LITTLE MORE QPF THAN THE ECMWF...BUT THE LATEST ECMWF IS NOW SHOWING VERY LIGHT ACCUMULATIONS WITH THE SUPERBLEND YET ADOPT THIS. HAVE SHOWN A VERY SMALL INCREASE IN POPS DURING THE TUESDAY EVENING TIME PERIOD...WHICH COULD DEFINITELY SEE SOME INCREASE IF CURRENT TRENDS CONTINUE. TEMPERATURES THROUGH THIS PERIOD WILL VARY LITTLE WITH GENERALLY WARMER THAN NORMAL READINGS AND DRY CONDITIONS. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 157 AM MST SUN DEC 20 2015 MID AND UPPER LEVEL PATTERN IS EXPECTED TO CHANGE FOR THESE PERIODS POSSIBLY LEADING TO COOLER TEMPERATURES AND PRECIP CHANCES RETURNING. WEDNESDAY...SHORTWAVE TROUGH PASSING THROUGH W/NW FLOW ACROSS THE NORTHERN PLAINS SHOULD KICK A WEAK COLD FRONT SOUTH. DESPITE VARIANCES IN STRENGTH OF THIS FEATURE THERE WOULD BE SOME FORCING AND MODELS ARE SHOWING LIGHT QPF. HOWEVER MOISTURE PROFILES CONTINUE TO INDICATE A DEEP DRY LAYER OVER OUR CWA BELONG 500 MB AND CONFIDENCE IN ANYTHING REACHING THE GROUND IS LOW. THURSDAY-SUNDAY...THERE IS SIGNIFICANT VARIANCE IN THE EVOLUTION OF A CLOSED UPPER LOW EXPECTED TO DEVELOP OVER THE WESTERN US AND EVENTUALLY MOVE ACROSS THE PLAINS DURING THESE PERIODS. CURRENT TREND IS TOWARDS LOWERING HEIGHTS AND COOLER TEMPERATURES THAN PREVIOUSLY INDICATED AND BLEND REFLECTED THIS AND THIS SHOULD MINIMIZE ERROR IN THIS HIGHLY UNCERTAIN PATTERN. FOR EXAMPLE...THE TIMING OF A COLD FRONT VARIES BY ALMOST 12HR BETWEEN MODELS RESULTING IN A HIGH DEGREE OF UNCERTAINTY ON HIGH TEMPS CHRISTMAS WITH GFS INDICATING HIGHS POSSIBLY AROUND FREEZING...WHILE ECMWF KEEPS PREFRONTAL TROUGH AND WAA IN PLACE CHRISTMAS DAY (HIGHS IN 50S). HOW THIS SYSTEM EVOLVES WILL IMPACT BOTH TEMP PROFILES (PRECIP TYPE) AND ANY CHANCE FOR MEASURABLE PRECIP. LATEST ECMWF INDICATES THE POSSIBLY FOR A WINTER STORM DEVELOPING OVER OUR CWA BY SATURDAY NIGHT. GFS SHOWS THE OPPOSITE AND HAS BEST CHANCE FOR PRECIP (LIKELY SNOW) THURSDAY NIGHT AND THEN DRY THROUGH THE REMAINING PERIODS AS THE CLOSED MID/UPPER LOW DRIFTS TO THE SOUTHWEST. 00Z GEFS ENSEMBLES SHOW A HIGH DEGREE OF VARIANCE WITH MEMBERS SHOWING LITTLE IN THE WAY OF CLUSTERING TOWARDS ANY ONE SOLUTION. IT MIGHT BE TEMPTING TO FAVOR THE GFS SOLUTION IN THE SPIRIT OF THE HOLIDAYS AND THE DESIRE FOR A LIGHT LAYER OF SNOW CHRISTMAS MORNING BUT THERE IS JUST NOT ENOUGH SUPPORT OR CONSISTENCY. THE ECMWF IS CONCERNING CONSIDERING THE BUSY TRAVEL WEEKEND...BUT AGAIN THERE IS NO RUN TO RUN HISTORY TO BUY INTO THIS ONE SOLUTION. I STAYED IN LINE WITH MEAN/BLEND APPROACH AND KEPT 20 POPS IN PLACE THURSDAY NIGHT (CHRISTMAS EVE NIGHT) THROUGH SATURDAY NIGHT OVER PARTS OF OUR CWA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 930 PM MST SAT DEC 19 2015 FOR KGLD AND KMCK...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. WINDS AT KGLD FROM THE SOUTHWEST NEAR 12KTS FROM TAF ISSUANCE THROUGH 08Z THEN A GRADUAL VEERING TO THE WEST-NORTHWEST BY 15Z...NORTHWEST FROM 20Z THROUGH THE REST OF THE TAF PERIOD. SPEEDS GENERALLY UNDER 10KTS. FOR KMCK...LIGHT AND VARIABLE WINDS FROM TAF ISSUANCE THROUGH 17Z THEN NORTHWEST 6-10KTS FROM 18Z THROUGH THE REST OF THE TAF PERIOD. MID AND MOSTLY HIGH CLOUDS EXPECTED THROUGH THE PERIOD. HAVE A BIT OF CONCERN IN THE 22Z-04Z TIMEFRAME AT BOTH TERMINALS. ITS DURING THIS TIME THAT AN UPPER TROUGH OF LOW PRESSURE MOVES ACROSS THE AREA. NAM MOISTURE CROSS SECTIONS SHOW LOW LEVEL MOISTURE INCREASING WITH THE TROUGH PASSAGE POSSIBLY CREATING SOME MVFR CLOUDINESS AND POSSIBLY SOME LIGHT RAIN SHOWERS. HRRR MODEL ALSO SHOWING SOME LIGHT PRECIP AS WELL. WILL HOLD OFF ON INTRODUCING ANY PRECIP MENTION AS CURRENT FORECAST IS DRY. WILL ALSO HOLD OFF ANY SUB VFR CLOUDINESS AS THE NAM APPEARS TO BE THE ONLY MODEL SHOWING MVFR CIGS AT PRESENT TIME. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...LOCKHART LONG TERM...DR AVIATION...99
AREA FORECAST DISCUSSION
NWS JACKSON KY
1103 AM EST SUN DEC 20 2015 .UPDATE... ISSUED AT 1102 AM EST SUN DEC 20 2015 TEMPERATURES HAVE BEGUN TO RISE ACROSS THE AREA THIS MORNING...THOUGH SLOWLY DUE TO INCREASING UPPER LEVEL CLOUD COVER. HAVE ADJUSTED TEMPS AND CLOUD COVER WITH THIS UPDATE. UPDATE ISSUED AT 640 AM EST SUN DEC 20 2015 A BAND OF CIRRUS SLIPPED OVER THE CWA DURING THE PAST COUPLE OF HOURS AND THEY LIKELY HELPED TO SLOW THE TEMPERATURE DROP IN THE VALLEYS AND ELSEWHERE. ACCORDINGLY...HAVE TWEAKED THE SKY COVER AND T/TD GRIDS PER THE LATEST OBS AND TRENDS. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 345 AM EST SUN DEC 20 2015 07Z SFC ANALYSIS SHOWS HIGH PRESSURE STARTING TO SLIP OFF TO THE EAST. BEFORE IT GOES IT IS GIVING THE AREA ONE MORE CHILLY NIGHT ALONG WITH A DECENT SIZED RIDGE TO VALLEY TEMPERATURE SPLIT. CLEAR SKIES BENEATH THE HIGH ALONG WITH LIGHT SFC WINDS AND A DRY AIR MASS HAS RESULTED IN VALLEY TEMPERATURES HAVEN FALLEN TO NEAR 20 DEGREES. MEANWHILE...THE RIDGES ARE CLOSER TO FREEZING WHILE DEWPOINTS THROUGHOUT THE AREA ARE CROWDING THE 20 DEGREE MARKER. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST. THEY ALL DEPICT A FLAT RIDGE CROSSING THE TENNESSEE VALLEY WITH HEIGHT RISES ON TAP FOR KENTUCKY TODAY. A SHORTWAVE TROUGH WILL THEN MOVE INTO THE SOUTHERN PLAINS TONIGHT PLACING OUR AREA DOWNSTREAM IN BROAD SOUTHWEST FLOW. SOME WEAK ENERGY WAVES WILL PASS THROUGH EASTERN KENTUCKY BY MONDAY MORNING WITH THE MAIN WAVE TAKING A TRACK TO THE NORTHWEST OF KENTUCKY. SOUTHWEST FLOW WILL CONTINUE INTO MONDAY EVENING AS ANOTHER TROUGH AND ENERGY BATCH HEAD FOR THE STATE FROM THE WEST. GIVEN THE GENERAL MODEL AGREEMENT HAVE AGAIN FAVORED THE HIGHER RESOLUTION HRRR AND NAM12 FOR WEATHER DETAILS. SENSIBLE WEATHER WILL FEATURE ANOTHER CHILLY START THIS MORNING... BUT PLENTY OF SUNSHINE WILL OVERCOME THAT YIELDING AFTERNOON TEMPERATURES IN THE 50 TO 55 DEGREE RANGE. HIGH CLOUDS WILL ARRIVE AND THICKEN WITH TIME THIS AFTERNOON INTO THE NIGHT AHEAD OF A QUICK MOVING COLD FRONT INBOUND FROM THE WEST. THIS FRONT WILL BRING ANOTHER ROUND OF SHOWERS TO THE CWA FOR MONDAY...THOUGH THE BEST MOISTURE AND HIGHEST PCPN CHANCES SPLIT THE AREA TO THE NORTH AND SOUTH. WHILE SOME EASTERN VALLEYS WILL FALL BELOW FREEZING TONIGHT...EXPECT THE FRONT/S APPROACH TO STIR THE AIR ENOUGH TO KEEP THEM FROM BEING THAT COLD WHEN THE FIRST RAIN CHANCES ARRIVE...SO HAVE LEFT ANY MIX CHANCES OF PCPN OUT OF THE FORECAST FOR NOW. THE FRONT WILL THEN STALL OVERHEAD THAT WITH THE NEXT SURGE OF MOISTURE LIKELY RIDING NORTH INTO THIS PART OF THE STATE LATER MONDAY NIGHT. FOR TEMPERATURES AND DEWPOINTS...HAVE AGAIN STARTED WITH THE SHORTBLEND GRIDS THROUGH TONIGHT FOLLOWED BY THE SUPERBLEND INTO MONDAY EVENING. DID AGAIN MAKE SOME MORE SIGNIFICANT ADJUSTMENTS TO THE LOWS TONIGHT...ESPECIALLY IN THE EASTERN VALLEYS DUE TO THE ANTICIPATION OF AN EARLY TEMPERATURE DROP OFF THIS EVENING FOLLOWED BY RISING TEMPS TOWARD DAWN FOR THE MOST SHELTERED LOCATIONS. AS FOR POPS...ENDED UP ON THE HIGHER SIDE OF ALL MOS FOR MONDAY...BUT CLOSEST TO THE MAV NUMBERS. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 315 AM EST SUN DEC 20 2015 VERY MILD AND POTENTIALLY RECORD BREAKING WARMTH WILL REMAIN THE MAIN HEADLINE AS WE HEAD THROUGH CHRISTMAS WEEK. IN ADDITION TO THE WARMTH...PLENTY OF CHANCES FOR RAIN WILL BE SEEN. STRONG RIDGING WILL BE IN PLACE ACROSS THE EASTERN CONUS THROUGH ALL OF CHRISTMAS WEEK. STARTING OFF TUESDAY NIGHT...A POTENT SHORTWAVE WILL MOVE NORTHEAST ACROSS THE OHIO RIVER VALLEY ALONG A STALLED OUT COLD FRONT. THIS WILL BRING INCREASING RAIN CHANCES THROUGH THE OVERNIGHT HOURS. FORCING WITH THIS WAVE WILL EXIT NORTH EARLY TUESDAY MORNING...WITH SUBSIDENCE BUILDING IN BEHIND THE DEPARTING WAVE ON TUESDAY. TEMPERATURES WILL CLIMB INTO THE 60S ON TUESDAY ALTHOUGH WE`LL HAVE A TOUGH TIME GETTING RID OF THE CLOUDS. A SECONDARY WAVE WILL LIFT NORTH TUESDAY NIGHT AND BRING ANOTHER ROUND OF RAIN SHOWERS TO EASTERN KENTUCKY. STILL SOME UNCERTAINTY ON THE EXTENT OF RAIN CHANCES AND HOW SOUTHEAST DOWNSLOPING FLOW IMPACTS OUR RAIN CHANCES. HOWEVER...WILL GO WITH HIGHEST POPS IN THE WEST...TO LOWER POPS IN THE EAST. ON WEDNESDAY...WE MAY SEE ANOTHER LULL AS SUBSIDENCE SPREADS BACK IN BEHIND THE DEPARTING WAVE. WITH EVEN WARMER BOUNDARY LAYER CONDITIONS IN PLACE...WE COULD BE EASILY PUSHING 70...WITH GUIDANCE SUGGESTING WIDESPREAD LOWER 70S. THIS WOULD EXCEED OUR RECORDS FOR WEDNESDAY BY 5 TO 8 DEGREES. FINALLY...A COLD FRONT WILL WORK EAST ACROSS THE AREA WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING...BRINGING ANOTHER SURGE OF RAIN. THIS TIME AROUND...THE FRONT SHOULD MOVE ON EAST...BRINGING A TEMPORARY END TO THE RAIN CHANCES. HIGH PRESSURE SHOULD KEEP THE WEATHER DRY FROM LATE THURSDAY MORNING THROUGH CHRISTMAS MORNING. HOWEVER...MODELS ARE TRENDING FASTER WITH BRINGING RAIN CHANCES. IF THIS OCCURS...WE WILL CERTAINLY BRING POPS BACK INTO THE AREA ON CHRISTMAS AS A WARM FRONT QUICKLY SURGES BACK TO THE NORTH. THIS WILL NOT ONLY MEAN A WARMER CHRISTMAS...BUT A WETTER ONE AS WELL. AS WE HEAD INTO THE WEEKEND...MODELS ARE HAVING A TOUGH TIME ON HOW THINGS EVOLVE...BUT CERTAINLY COULD BE SOME WET WEATHER AT SOME POINT OVER THE WEEKEND AS A DEEP SYSTEM ORGANIZES SOMEWHERE OVER THE CENTRAL OR EASTERN US. FOR THIS REASON WILL KEEP SOME CHANCE POPS IN THE FORECAST THROUGH THE WEEKEND. IT DOES LOOK LIKE WE SHOULD REMAIN MILD THROUGH THE WEEKEND...WITH PERHAPS A BRIEF COOL DOWN AS WE HEAD INTO THE FOLLOW WEEK. HOWEVER...THERE IS MUCH UNCERTAINTY IN THE FORECAST BEYOND CHRISTMAS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 700 AM EST SUN DEC 20 2015 HIGH PRESSURE WILL REMAIN IN CONTROL ACROSS THE REGION THROUGH THE TAF PERIOD PROVIDING VFR CONDITIONS UNDER THICKENING HIGH CLOUDS. AN APPROACHING COLD FRONT WILL BRING IN A DECK OF MID LEVEL CLOUD TOWARD DAWN ON MONDAY. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE BULK OF THE PERIOD WITH SOME STIRRING FROM THE SOUTH ANTICIPATED BY 12Z MONDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SHALLENBERGER SHORT TERM...GREIF LONG TERM...KAS AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
700 AM EST SUN DEC 20 2015 .UPDATE... ISSUED AT 640 AM EST SUN DEC 20 2015 A BAND OF CIRRUS SLIPPED OVER THE CWA DURING THE PAST COUPLE OF HOURS AND THEY LIKELY HELPED TO SLOW THE TEMPERATURE DROP IN THE VALLEYS AND ELSEWHERE. ACCORDINGLY...HAVE TWEAKED THE SKY COVER AND T/TD GRIDS PER THE LATEST OBS AND TRENDS. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 345 AM EST SUN DEC 20 2015 07Z SFC ANALYSIS SHOWS HIGH PRESSURE STARTING TO SLIP OFF TO THE EAST. BEFORE IT GOES IT IS GIVING THE AREA ONE MORE CHILLY NIGHT ALONG WITH A DECENT SIZED RIDGE TO VALLEY TEMPERATURE SPLIT. CLEAR SKIES BENEATH THE HIGH ALONG WITH LIGHT SFC WINDS AND A DRY AIR MASS HAS RESULTED IN VALLEY TEMPERATURES HAVEN FALLEN TO NEAR 20 DEGREES. MEANWHILE...THE RIDGES ARE CLOSER TO FREEZING WHILE DEWPOINTS THROUGHOUT THE AREA ARE CROWDING THE 20 DEGREE MARKER. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST. THEY ALL DEPICT A FLAT RIDGE CROSSING THE TENNESSEE VALLEY WITH HEIGHT RISES ON TAP FOR KENTUCKY TODAY. A SHORTWAVE TROUGH WILL THEN MOVE INTO THE SOUTHERN PLAINS TONIGHT PLACING OUR AREA DOWNSTREAM IN BROAD SOUTHWEST FLOW. SOME WEAK ENERGY WAVES WILL PASS THROUGH EASTERN KENTUCKY BY MONDAY MORNING WITH THE MAIN WAVE TAKING A TRACK TO THE NORTHWEST OF KENTUCKY. SOUTHWEST FLOW WILL CONTINUE INTO MONDAY EVENING AS ANOTHER TROUGH AND ENERGY BATCH HEAD FOR THE STATE FROM THE WEST. GIVEN THE GENERAL MODEL AGREEMENT HAVE AGAIN FAVORED THE HIGHER RESOLUTION HRRR AND NAM12 FOR WEATHER DETAILS. SENSIBLE WEATHER WILL FEATURE ANOTHER CHILLY START THIS MORNING... BUT PLENTY OF SUNSHINE WILL OVERCOME THAT YIELDING AFTERNOON TEMPERATURES IN THE 50 TO 55 DEGREE RANGE. HIGH CLOUDS WILL ARRIVE AND THICKEN WITH TIME THIS AFTERNOON INTO THE NIGHT AHEAD OF A QUICK MOVING COLD FRONT INBOUND FROM THE WEST. THIS FRONT WILL BRING ANOTHER ROUND OF SHOWERS TO THE CWA FOR MONDAY...THOUGH THE BEST MOISTURE AND HIGHEST PCPN CHANCES SPLIT THE AREA TO THE NORTH AND SOUTH. WHILE SOME EASTERN VALLEYS WILL FALL BELOW FREEZING TONIGHT...EXPECT THE FRONT/S APPROACH TO STIR THE AIR ENOUGH TO KEEP THEM FROM BEING THAT COLD WHEN THE FIRST RAIN CHANCES ARRIVE...SO HAVE LEFT ANY MIX CHANCES OF PCPN OUT OF THE FORECAST FOR NOW. THE FRONT WILL THEN STALL OVERHEAD THAT WITH THE NEXT SURGE OF MOISTURE LIKELY RIDING NORTH INTO THIS PART OF THE STATE LATER MONDAY NIGHT. FOR TEMPERATURES AND DEWPOINTS...HAVE AGAIN STARTED WITH THE SHORTBLEND GRIDS THROUGH TONIGHT FOLLOWED BY THE SUPERBLEND INTO MONDAY EVENING. DID AGAIN MAKE SOME MORE SIGNIFICANT ADJUSTMENTS TO THE LOWS TONIGHT...ESPECIALLY IN THE EASTERN VALLEYS DUE TO THE ANTICIPATION OF AN EARLY TEMPERATURE DROP OFF THIS EVENING FOLLOWED BY RISING TEMPS TOWARD DAWN FOR THE MOST SHELTERED LOCATIONS. AS FOR POPS...ENDED UP ON THE HIGHER SIDE OF ALL MOS FOR MONDAY...BUT CLOSEST TO THE MAV NUMBERS. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 315 AM EST SUN DEC 20 2015 VERY MILD AND POTENTIALLY RECORD BREAKING WARMTH WILL REMAIN THE MAIN HEADLINE AS WE HEAD THROUGH CHRISTMAS WEEK. IN ADDITION TO THE WARMTH...PLENTY OF CHANCES FOR RAIN WILL BE SEEN. STRONG RIDGING WILL BE IN PLACE ACROSS THE EASTERN CONUS THROUGH ALL OF CHRISTMAS WEEK. STARTING OFF TUESDAY NIGHT...A POTENT SHORTWAVE WILL MOVE NORTHEAST ACROSS THE OHIO RIVER VALLEY ALONG A STALLED OUT COLD FRONT. THIS WILL BRING INCREASING RAIN CHANCES THROUGH THE OVERNIGHT HOURS. FORCING WITH THIS WAVE WILL EXIT NORTH EARLY TUESDAY MORNING...WITH SUBSIDENCE BUILDING IN BEHIND THE DEPARTING WAVE ON TUESDAY. TEMPERATURES WILL CLIMB INTO THE 60S ON TUESDAY ALTHOUGH WE`LL HAVE A TOUGH TIME GETTING RID OF THE CLOUDS. A SECONDARY WAVE WILL LIFT NORTH TUESDAY NIGHT AND BRING ANOTHER ROUND OF RAIN SHOWERS TO EASTERN KENTUCKY. STILL SOME UNCERTAINTY ON THE EXTENT OF RAIN CHANCES AND HOW SOUTHEAST DOWNSLOPING FLOW IMPACTS OUR RAIN CHANCES. HOWEVER...WILL GO WITH HIGHEST POPS IN THE WEST...TO LOWER POPS IN THE EAST. ON WEDNESDAY...WE MAY SEE ANOTHER LULL AS SUBSIDENCE SPREADS BACK IN BEHIND THE DEPARTING WAVE. WITH EVEN WARMER BOUNDARY LAYER CONDITIONS IN PLACE...WE COULD BE EASILY PUSHING 70...WITH GUIDANCE SUGGESTING WIDESPREAD LOWER 70S. THIS WOULD EXCEED OUR RECORDS FOR WEDNESDAY BY 5 TO 8 DEGREES. FINALLY...A COLD FRONT WILL WORK EAST ACROSS THE AREA WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING...BRINGING ANOTHER SURGE OF RAIN. THIS TIME AROUND...THE FRONT SHOULD MOVE ON EAST...BRINGING A TEMPORARY END TO THE RAIN CHANCES. HIGH PRESSURE SHOULD KEEP THE WEATHER DRY FROM LATE THURSDAY MORNING THROUGH CHRISTMAS MORNING. HOWEVER...MODELS ARE TRENDING FASTER WITH BRINGING RAIN CHANCES. IF THIS OCCURS...WE WILL CERTAINLY BRING POPS BACK INTO THE AREA ON CHRISTMAS AS A WARM FRONT QUICKLY SURGES BACK TO THE NORTH. THIS WILL NOT ONLY MEAN A WARMER CHRISTMAS...BUT A WETTER ONE AS WELL. AS WE HEAD INTO THE WEEKEND...MODELS ARE HAVING A TOUGH TIME ON HOW THINGS EVOLVE...BUT CERTAINLY COULD BE SOME WET WEATHER AT SOME POINT OVER THE WEEKEND AS A DEEP SYSTEM ORGANIZES SOMEWHERE OVER THE CENTRAL OR EASTERN US. FOR THIS REASON WILL KEEP SOME CHANCE POPS IN THE FORECAST THROUGH THE WEEKEND. IT DOES LOOK LIKE WE SHOULD REMAIN MILD THROUGH THE WEEKEND...WITH PERHAPS A BRIEF COOL DOWN AS WE HEAD INTO THE FOLLOW WEEK. HOWEVER...THERE IS MUCH UNCERTAINTY IN THE FORECAST BEYOND CHRISTMAS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 700 AM EST SUN DEC 20 2015 HIGH PRESSURE WILL REMAIN IN CONTROL ACROSS THE REGION THROUGH THE TAF PERIOD PROVIDING VFR CONDITIONS UNDER THICKENING HIGH CLOUDS. AN APPROACHING COLD FRONT WILL BRING IN A DECK OF MID LEVEL CLOUD TOWARD DAWN ON MONDAY. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE BULK OF THE PERIOD WITH SOME STIRRING FROM THE SOUTH ANTICIPATED BY 12Z MONDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...GREIF LONG TERM...KAS AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS BILLINGS MT
311 AM MST SUN DEC 20 2015 .SHORT TERM...VALID FOR TDY AND MON... A VERY PROGRESSIVE PATTERN WILL BE OVER SOUTHERN MONTANA AND NORTHERN WYOMING THROUGH THE EARLY PART OF THE WEEK. THE FAST MOVING NATURE OF THE ENERGY AND LACK OF AN AMPLIFIED PATTERN WILL PREVENT A STRONG SURGE OF ARCTIC AIR AND THE DEVELOPMENT OF A LARGE SNOW PRODUCING SYSTEM. A COUPLE OF DIFFERENT SYSTEMS WILL WORK THROUGH AND PRODUCE AREAS OF SNOW SHOWERS...BUT THE SYSTEMS WILL BE FAST MOVING AND THIS IN TURN WILL KEEP SNOW ACCUMULATIONS DOWN. THE MOST LIKELY LOCATION TO SEE ACCUMULATING SNOW WILL BE THE SOUTHWEST MOUNTAINS WITH A STEADY STREAM OF MOISTURE FEEDING INTO THE WESTERN SLOPES. ONE SYSTEM MOVED ACROSS CENTRAL ZONES OVERNIGHT AND WILL SLIDE ACROSS SOUTHERN MONTANA THIS MORNING. THIS ENERGY IS PROGGED TO WEAKEN AS IT PROGRESSES EASTWARD...SO SNOW SHOWER ACTIVITY ASSOCIATED WITH IT WILL BE LESS DYNAMIC THAN IT WAS OVER WESTERN AND CENTRAL ZONES OVERNIGHT. WILL LINGER LOW POPS OVER THE SOUTHERN HALF OF THE AREA THIS MORNING. AREAS OF FOG FORMED BEHIND THE BAND OF LIGHT TO MODERATE SNOW THAT WORKED THROUGH OVERNIGHT. HI RESOLUTION MODELS INDICATE THAT SOME LOW CEILINGS AND FOG WILL PERSIST OVER PARTS OF THE MORNING. RAP SOUNDINGS KEEP LOW CLOUDS AND SOME FOG IN BILLINGS THROUGH 16Z...THEN LIFT IT OUT AS STRONGER MIXING WINDS FORM IN THE LOWER LEVELS WITH A LEE TROUGH FORMING. ADDED AREAS OF FOG FOR PARTS OF THE AREA FOR THE MORNING. THE NEXT SHORTWAVE TO ADVANCE THROUGH THE AREA WILL BE SUNDAY NIGHT AND EARLY MONDAY. THIS SYSTEM DOES PACK SOME INSTABILITY WITH LAPSE RATES OF AROUND 8C/KM FROM 850-500MB. THE MAIN CORE OF THE WAVE RIDES ACROSS NORTHERN MONTANA...WHICH IS NOT IN A GOOD LOCATION FOR PRECIPITATION CHANCES. HAVE BRUSHED SOME LOW POPS IN DUE TO INSTABILITY AND OVERALL STRENGTH OF THE SHORTWAVE TROUGH. MAY NEED TO RAISE POPS IN FUTURE UPDATES IF THE CORE TRACKS A LITTLE FARTHER SOUTH. YET ANOTHER WAVE WORKS IN MONDAY NIGHT INTO TUESDAY MORNING FOR A CHANCE OF SNOW SHOWERS. THIS SYSTEM WAS TRACKING A LITTLE FARTHER SOUTH THUS MAY HAVE A BETTER CHANCE OF PRODUCING SNOW SHOWERS FOR THE FORECAST AREA. TEMPERATURES THE NEXT COUPLE OF DAY SHOULD BE RIGHT AROUND SEASONAL AVERAGES. TWH .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... EXTENDED MODELS WERE IN OVERALL AGREEMENT THROUGH THE PERIOD IN SHOWING A PROGRESSIVE WESTERLY FLOW WITH MULTIPLE WAVES MOVING THROUGH THE FLOW. MODELS CONTINUE TO BRING A SPLITTING TROUGH INTO THE REGION THU NIGHT THROUGH FRI NIGHT. THE MODELS HANDLE THIS FEATURE DIFFERENTLY INTO SAT. THE GFS AND ECMWF SHOW MOISTURE OVER THE AREA IN W FLOW THU NIGHT THEN DRY OUT THE MOISTURE ON FRI/FRI NIGHT. ECMWF HINTS AT TRYING TO BRING WRAP-AROUND MOISTURE FROM A 700 MB LOW INTO THE SE BY SAT MORNING. THESE PERIODS APPEAR TO BE IN FLUX BASED ON HOW THE MODELS LOOKED LAST NIGHT...SO TO FOLLOW TRENDS...JUST HAVE LOW POPS OVER PORTIONS OF THE AREA THROUGH FRI NIGHT. ANOTHER DIFFERENCE WITH THESE NEW MODEL RUNS IS HOW THE PRESSURE GRADIENT SETS UP QUITE STRONGLY OVER THE AREA ON SAT AND CONTINUES INTO SUN WITH SOME DIFFERENCES BETWEEN THE MODELS ON HOW THE GRADIENT SETS UP. BASED ON THE GRADIENT STRENGTH...HAVE INCREASED GAP FLOW WINDS INTO THE ADVISORY/WARNING CRITERIA WIND SPEEDS DURING THIS TIME FRAME. WILL DEFINITELY NEED TO WATCH MODEL TRENDS TO SEE IF THIS PATTERN PERSISTS FROM RUN-TO-RUN. OTHERWISE...MODELS BRING A SHORTWAVE THROUGH THE AREA ON TUE WITH MORE ENERGY ON WED. WEAKER ENERGY FOLLOWS ON THU. NEAR-NORMAL TEMPERATURES WILL CONTINUE WITH CHANCES FOR SNOW EACH PERIOD...ESPECIALLY IN THE MOUNTAINS. FRI WILL BE THE COLDEST DAY WITH 850 MB TEMPERATURES AROUND -8 DEGREES C...THEN TEMPERATURES WILL MODERATE THROUGH THE WEEKEND. ARTHUR && .AVIATION... VLIFR CONDITIONS ARE EXPECTED TO PERSIST AT KBIL UNTIL AROUND 17Z. AFTERWARD...CONDITIONS WILL IMPROVE TO MVFR. THE FOG MAY RETURN TONIGHT BUT CONFIDENCE IN THIS OCCURRING IS NOT VERY HIGH AT THIS TIME. MVFR/IFR CONDITIONS IN SNOW AND FOG OVER KMLS WILL CONTINUE THIS MORNING...THEN LOW CEILINGS WILL REMAIN INTO TONIGHT. MVFR TO LIFR CONDITIONS IN KSHR WILL IMPROVE BY 18Z...WITH VFR EXPECTED THIS AFTERNOON AND TONIGHT. MVFR CONDITIONS ARE POSSIBLE IN KLVM EARLY THIS MORNING...OTHERWISE VFR WILL PREVAIL THROUGH TONIGHT. THE BEARTOOTHS/ABSAROKAS AND NE BIG HORNS WILL BE MOSTLY OBSCURED TODAY. OBSCURATIONS WILL CONTINUE TONIGHT FOR THE BEARTOOTHS/ABSAROKAS. THERE WILL BE AREAS OF OBSCURATION OVER THE CRAZYS AND NE BIG HORNS. ARTHUR && .PRELIMINARY POINT TEMP/POPS... TDY MON TUE WED THU FRI SAT ------------------------------------------------------- BIL 033 021/034 021/035 020/031 015/027 007/022 009/028 2/S 21/N 22/J 23/J 21/E 11/B 11/N LVM 035 021/032 022/034 019/028 016/027 006/021 009/026 2/S 32/S 43/J 43/J 22/J 22/J 11/N HDN 034 018/036 017/036 014/034 009/028 002/020 000/027 2/S 21/B 22/W 23/J 21/E 11/B 11/U MLS 032 020/035 016/033 014/029 010/026 005/023 005/026 1/E 12/S 12/J 23/J 21/E 11/E 11/U 4BQ 033 019/036 017/035 015/029 008/027 005/023 008/027 2/S 12/S 11/E 23/J 21/E 11/E 11/U BHK 031 019/034 017/033 015/027 013/027 008/023 009/029 1/E 02/S 01/E 32/J 21/E 11/E 11/B SHR 033 017/035 017/036 014/029 008/027 004/023 004/029 3/S 12/S 22/J 23/J 21/B 12/J 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS ELKO NV
242 AM PST SUN DEC 20 2015 .SYNOPSIS...A SLEW OF PACIFIC STORMS WILL PUSH INTO THE GREAT BASIN THIS WEEK. THE FIRST SHOT OF MOISTURE IS EXPECTED LATER TODAY BUT ONLY FOR NORTHERN NEVADA. THE MAIN EVENT WILL BE THE MONDAY AND TUESDAY STORM WHICH WILL DUMP MOISTURE ACROSS NORTHERN AND CENTRAL NEVADA. THIS MONDAY TUESDAY STORM WILL BRING SEVERAL INCHES OF SNOW TO MOST VALLEY LOCATIONS AND WILL YIELD HEFTY AMOUNTS OF SNOW IN THE MOUNTAINS. ANOTHER SYSTEM IS EXPECTED ON THURSDAY...WHICH WILL ALSO BRING SNOW TO THE REGION. && .SHORT TERM...TODAY THROUGH TUESDAY. THE LATEST RADAR IMAGE FROM KLRX HAS ISOLATED SHOWERS OVER PORTIONS OF ELKO...LANDER AND EUREKA COUNTIES. THE HRRR HAS THESE POCKETS OF MOISTURE PETERING OUT THIS MORNING. BUT UPSTREAM...THE HRRR HAS A BOUNTY OF QPF JUST WEST OF THE LKN...THAT WILL GRADUALLY PUSH INTO HUMBOLDT COUNTY. THE PRIMARY FORCING MECHANISM WILL BE ISENTROPIC LIFT. THE QPF WILL BE CONTAINED IN THE NORTHERN LKN ZONES. THE STORM THAT EVERYONE HAS BEEN WATCHING IS THE MONDAY-TUESDAY EVENT...WHEN THE ATMOSPHERIC RIVER SUCCESSFULLY PUSHES BEYOND THE COASTAL RANGES AND SIERRA. THE NAM AND THE GFS...BOTH DEPICT A BOATLOAD OF QPF. THE MAIN DIFFERENCE IS THE AMOUNT OF COLD AIR PRESENT. THIS PACKAGE REFLECTS THE WARMER GFS SOLUTION WHICH IMPACTS THE SNOW RATIOS AND THE SNOW GRIDS. HIGH CONFIDENCE THAT THIS WILL BE A MAJOR QPF EVENT...NOT AS CONFIDENT ABOUT THE SNOW AMOUNTS IN THE VALLEY FLOORS. KEPT THE WATCH IN PLACE...BUT DID NOT UPGRADE IT AT THIS TIME. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY. MODELS LARGELY AGREE ON NORTHWEST FLOW WITH A TIGHT THERMAL GRADIENT ALOFT THROUGH EARLY THURSDAY. EMBEDDED SHORT WAVES WILL KEEP POPS IN THE PICTURE...TAPERING QUICKLY OFF FROM TUESDAY`S STORM. WEDNESDAY WILL BE RELATIVELY "DRY" BUT NOT POPLESS...BY COMPARISON ONLY. 00Z RUNS OF BOTH LONG RANGE MODELS SHOWS THE QUASI-ZONAL FLOW BUCKLING AS A SHORT WAVE DIGS ALONG THE COAST STARTING WEDNESDAY NIGHT AND REACHING THE GREAT BASIN BY THURSDAY MID DAY. POPS INCREASE DRAMATICALLY CHRISTMAS EVE AND RUN THROUGH CHRISTMAS. IT`S LIKELY THAT MOST OF NORTHERN NEVADA WILL HAVE A WHITE CHRISTMAS. IT`S POSSIBLE THE EASTERN NEVADA WILL...AND THERE`S HOPE FOR EVEN NORTHERN NYE COUNTY. AMOUNTS? TOO SOON TO TELL...BUT THE UPPER DYNAMICS ARE THERE AT LEAST IN THE MODELS. DISPLACEMENT OF A JET STREAK WILL TELL...HOWEVER. ON THE WEEKEND...A RIDGE BUILDS IN ADVANCE OF THE ***NEXT*** SHORT WAVE...BUT ITS ORIENTATION AND PLACEMENT ETC ARE NOT AGREED UPON. HAVE THEREFORE KEPT SOME POPS IN BUT MUCH LOWER THAN THE CHRISTMAS TIME FRAME. WITH SNOW COVER...TEMPS WILL REMAIN DOWN DESPITE ANY RIDGING. && .AVIATION...QUICK BREAK SUNDAY MORNING BETWEEN BATCHES OF SNOW SHOWERS OVER NORTHERN NEVADA. A LONG STRETCH OF MOISTURE ARRIVES IN NORTHWEST NEVADA SUNDAY AFTERNOON AND REMAINS IN PLACE THROUGH 12Z MONDAY. MVFR CIGS/VISBY LIKELY AT KWMC...KEKO...KELY FROM SUNDAY AFTERNOON THROUGH 12Z MONDAY. VFR AT KTPH. OUTLOOK FOR LATE MONDAY INTO TUESDAY...BAD. POSSIBLY MOST SERIOUS WINTER STORM OF THE SEASON SO FAR. && .LKN WATCHES/WARNINGS/ADVISORIES... WINTER STORM WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING FOR HUMBOLDT COUNTY-NORTHERN ELKO COUNTY-NORTHERN LANDER COUNTY AND NORTHERN EUREKA COUNTY-RUBY MOUNTAINS AND EAST HUMBOLDT RANGE- SOUTH CENTRAL ELKO COUNTY-SOUTHWEST ELKO COUNTY. && $$ 97/98/98
AREA FORECAST DISCUSSION
NWS BISMARCK ND
917 AM CST SUN DEC 20 2015 .UPDATE... ISSUED AT 915 AM CST SUN DEC 20 2015 QUICK UPDATE TO ISSUE A DENSE FOG ADVISORY FOR NORTHWEST NORTH DAKOTA THROUGH 19 UTC GIVEN WEBCAM AND SURFACE OBSERVATION TRENDS THROUGH 15 UTC...AND A NEAR MINIMUM SOLAR ANGLE LIMITING INSOLATION TO LIFT THE FOG POST SUNRISE. UPDATE ISSUED AT 845 AM CST SUN DEC 20 2015 OVER THE PAST TWO HOURS THROUGH 1445 UTC...VISIBILITY HAS CONTINUED TO DECREASE IN FOG ACROSS WESTERN NORTH DAKOTA PER WEBCAM AND SURFACE OBSERVATIONS...WITH LOCALLY DENSE FOG IN SOME AREAS. WILL CONTINUE TO MONITOR TRENDS THIS MORNING SHOULD A DENSE FOG ADVISORY BECOME NECESSARY...AS THE 12-13 UTC HRRR AND 06 UTC NAM NEST SUGGEST FOG MAY CONTINUE TO EXPAND THROUGH THE MORNING. UPDATE ISSUED AT 609 AM CST SUN DEC 20 2015 SOME LIGHT SNOW HAS DEVELOPED STRETCHING FROM SOUTHWEST TOWARDS THE NORTHEAST ACROSS THE STATE WHICH HIGH-RES MODELS ARE NOT PICKING UP TO WELL. FOR MORNING UPDATES HAVE ADDED POPS TO THE FORECAST TO ADDRESS THIS. EXPECT THIS SNOW TO DIMINISH BY MID-DAY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM CST SUN DEC 20 2015 MAIN CHALLENGE IN THE SHORT TERM IS CLOUD COVER AND FOG POTENTIAL. CURRENTLY...AT THE SURFACE...COOL HIGH PRESSURE WAS CENTERED OVER HUDSON BAY WITH A RIDGE AXIS EXTENDING SOUTHWEST INTO SASKATCHEWAN. THE BOUNDARY BETWEEN THIS COOL HIGH PRESSURE AND MILDER AIR TO THE SOUTH WAS A WEAK LOW PRESSURE FRONT ACROSS FAR SOUTHERN SASKATCHEWAN. AT UPPER LEVELS...A LONGWAVE TROUGH EXTENDED OVER THE EASTERN ROCKIES AND WAS POISED TO EMERGE INTO THE FRONT RANGE. THE UPPER LEVEL TROUGH IS FORECAST TO MOVE EAST ACROSS THE DAKOTAS TODAY AND TONIGHT...BUT THE BASE OF THE TROUGH IS FORECAST TO DEEPEN NEAR THE 4-CORNERS AREA TODAY AND DEVELOP A STRONGER SHORTWAVE. THIS WILL WEAKEN THE TROUGHING FARTHER NORTH AND KEEP ANY FORCING FARTHER TO THE SOUTH OF NORTH DAKOTA TODAY. MEANWHILE THE SURFACE BOUNDARY IN SOUTHERN SASKATCHEWAN IS FORECAST TO DROP SOUTH ACROSS THE STATE THIS MORNING...BRINGING WITH IT THE COOLER AND MOIST AIR OF THE CANADIAN HIGH. SKIES SHOULD REMAIN CLOUDY OVER THE STATE WITH SOME PATCHY FOG THIS MORNING. THE AXIS OF THE SURFACE HIGH IS FORECAST TO MOVE SOUTHEAST AND EXTEND FROM MANITOBA ACROSS THE EASTERN DAKOTAS BY EVENING...WITH THE COOL HIGH PRESSURE RIDGE AXIS REMAINING OVER THE EASTERN DAKOTAS SUNDAY NIGHT. WHILE CLOUDS MAY DECREASE A BIT IN THE WEST THIS AFTERNOON...CLOUDS WILL LIKELY INCREASE IN THE WESTERN PART OF THE STATE TONIGHT AS THE COOL HIGH PRESSURE MOVES EAST AND A DEVELOPING TROUGH IN THE FRONT RANGE BRINGS SOME WARM ADVECTION AND VERTICAL MOTION TO WESTERN NORTH DAKOTA. HIGHS TODAY ARE EXPECTED TO BE IN THE TEENS TO LOWER 20S OVER NORTHERN AND CENTRAL PARTS OF THE STATE...WITH UPPER 20S AND LOWER 30S IN THE SOUTHWEST. MINIMUM TEMPERATURES SUNDAY NIGHT SHOULD RANGE FROM 5 TO 10 ABOVE OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA - CLOSER TO THE COOL RIDGE AXIS - TO THE TEENS IN THE WEST. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 323 AM CST SUN DEC 20 2015 HIGHLIGHT FOR THE EXTENDED PERIOD WILL BE THE OCCASIONAL SNOW CHANCES AS VARIOUS SHORT WAVES SLIDE THROUGH THE AREA WHILE TEMPERATURES REMAIN SEASONAL. ON MONDAY...FAST MOVING SHORT WAVE ZIPS THROUGH THE AREA BRINGING CHANCES FOR LIGHT SNOW AS IT MOVES THROUGH. ANY ACCUMULATIONS WILL BE MINIMAL. FOR TUESDAY...A STRONGER SHORT WAVE PUSHES INTO THE REGION AS A SURFACE LOW LIFTS THROUGH THE DAKOTAS. THIS WILL BRING INCREASING SNOW CHANCES OVER NORTHERN AND EASTERN LOCATIONS...WITH THE GREATEST CHANCES OVER NORTH CENTRAL NORTH DAKOTA WHERE AN INCH OR TWO OF NEW SNOW WILL BE POSSIBLE. LOW CHANCES FOR SNOW LINGER INTO WEDNESDAY. MAINLY QUIET WEATHER EXPECTED ON THURSDAY. GOING INTO THE HOLIDAY WEEKEND...MODELS HAVE SHIFTED SNOW CHANCES ON FRIDAY AND SATURDAY TO THE SOUTHEAST THOUGH ARE HAVING TROUBLE COMING TO A CONSENSUS ON SOME KEY FEATURES. WITH THAT SAID...WILL RETAIN SOME LOWER SNOW CHANCES MAINLY OVER SOUTHERN AND EASTERN LOCATIONS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 915 AM CST SUN DEC 20 2015 WIDESPREAD MVFR/IFR CONDITIONS IN STRATUS AND FOG THIS MORNING WILL TREND TOWARDS IFR/LIFR THIS AFTERNOON AND THROUGH THE NIGHT ACROSS WESTERN AND CENTRAL NORTH DAKOTA. && .BIS WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR NDZ001-002- 009-010. && $$ UPDATE...AYD SHORT TERM...JV LONG TERM...JJS AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
849 AM CST SUN DEC 20 2015 .UPDATE... ISSUED AT 845 AM CST SUN DEC 20 2015 OVER THE PAST TWO HOURS THROUGH 1445 UTC...VISIBILITY HAS CONTINUED TO DECREASE IN FOG ACROSS WESTERN NORTH DAKOTA PER WEBCAM AND SURFACE OBSERVATIONS...WITH LOCALLY DENSE FOG IN SOME AREAS. WILL CONTINUE TO MONITOR TRENDS THIS MORNING SHOULD A DENSE FOG ADVISORY BECOME NECESSARY...AS THE 12-13 UTC HRRR AND 06 UTC NAM NEST SUGGEST FOG MAY CONTINUE TO EXPAND THROUGH THE MORNING. UPDATE ISSUED AT 609 AM CST SUN DEC 20 2015 SOME LIGHT SNOW HAS DEVELOPED STRETCHING FROM SOUTHWEST TOWARDS THE NORTHEAST ACROSS THE STATE WHICH HIGH-RES MODELS ARE NOT PICKING UP TO WELL. FOR MORNING UPDATES HAVE ADDED POPS TO THE FORECAST TO ADDRESS THIS. EXPECT THIS SNOW TO DIMINISH BY MID-DAY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM CST SUN DEC 20 2015 MAIN CHALLENGE IN THE SHORT TERM IS CLOUD COVER AND FOG POTENTIAL. CURRENTLY...AT THE SURFACE...COOL HIGH PRESSURE WAS CENTERED OVER HUDSON BAY WITH A RIDGE AXIS EXTENDING SOUTHWEST INTO SASKATCHEWAN. THE BOUNDARY BETWEEN THIS COOL HIGH PRESSURE AND MILDER AIR TO THE SOUTH WAS A WEAK LOW PRESSURE FRONT ACROSS FAR SOUTHERN SASKATCHEWAN. AT UPPER LEVELS...A LONGWAVE TROUGH EXTENDED OVER THE EASTERN ROCKIES AND WAS POISED TO EMERGE INTO THE FRONT RANGE. THE UPPER LEVEL TROUGH IS FORECAST TO MOVE EAST ACROSS THE DAKOTAS TODAY AND TONIGHT...BUT THE BASE OF THE TROUGH IS FORECAST TO DEEPEN NEAR THE 4-CORNERS AREA TODAY AND DEVELOP A STRONGER SHORTWAVE. THIS WILL WEAKEN THE TROUGHING FARTHER NORTH AND KEEP ANY FORCING FARTHER TO THE SOUTH OF NORTH DAKOTA TODAY. MEANWHILE THE SURFACE BOUNDARY IN SOUTHERN SASKATCHEWAN IS FORECAST TO DROP SOUTH ACROSS THE STATE THIS MORNING...BRINGING WITH IT THE COOLER AND MOIST AIR OF THE CANADIAN HIGH. SKIES SHOULD REMAIN CLOUDY OVER THE STATE WITH SOME PATCHY FOG THIS MORNING. THE AXIS OF THE SURFACE HIGH IS FORECAST TO MOVE SOUTHEAST AND EXTEND FROM MANITOBA ACROSS THE EASTERN DAKOTAS BY EVENING...WITH THE COOL HIGH PRESSURE RIDGE AXIS REMAINING OVER THE EASTERN DAKOTAS SUNDAY NIGHT. WHILE CLOUDS MAY DECREASE A BIT IN THE WEST THIS AFTERNOON...CLOUDS WILL LIKELY INCREASE IN THE WESTERN PART OF THE STATE TONIGHT AS THE COOL HIGH PRESSURE MOVES EAST AND A DEVELOPING TROUGH IN THE FRONT RANGE BRINGS SOME WARM ADVECTION AND VERTICAL MOTION TO WESTERN NORTH DAKOTA. HIGHS TODAY ARE EXPECTED TO BE IN THE TEENS TO LOWER 20S OVER NORTHERN AND CENTRAL PARTS OF THE STATE...WITH UPPER 20S AND LOWER 30S IN THE SOUTHWEST. MINIMUM TEMPERATURES SUNDAY NIGHT SHOULD RANGE FROM 5 TO 10 ABOVE OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA - CLOSER TO THE COOL RIDGE AXIS - TO THE TEENS IN THE WEST. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 323 AM CST SUN DEC 20 2015 HIGHLIGHT FOR THE EXTENDED PERIOD WILL BE THE OCCASIONAL SNOW CHANCES AS VARIOUS SHORT WAVES SLIDE THROUGH THE AREA WHILE TEMPERATURES REMAIN SEASONAL. ON MONDAY...FAST MOVING SHORT WAVE ZIPS THROUGH THE AREA BRINGING CHANCES FOR LIGHT SNOW AS IT MOVES THROUGH. ANY ACCUMULATIONS WILL BE MINIMAL. FOR TUESDAY...A STRONGER SHORT WAVE PUSHES INTO THE REGION AS A SURFACE LOW LIFTS THROUGH THE DAKOTAS. THIS WILL BRING INCREASING SNOW CHANCES OVER NORTHERN AND EASTERN LOCATIONS...WITH THE GREATEST CHANCES OVER NORTH CENTRAL NORTH DAKOTA WHERE AN INCH OR TWO OF NEW SNOW WILL BE POSSIBLE. LOW CHANCES FOR SNOW LINGER INTO WEDNESDAY. MAINLY QUIET WEATHER EXPECTED ON THURSDAY. GOING INTO THE HOLIDAY WEEKEND...MODELS HAVE SHIFTED SNOW CHANCES ON FRIDAY AND SATURDAY TO THE SOUTHEAST THOUGH ARE HAVING TROUBLE COMING TO A CONSENSUS ON SOME KEY FEATURES. WITH THAT SAID...WILL RETAIN SOME LOWER SNOW CHANCES MAINLY OVER SOUTHERN AND EASTERN LOCATIONS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 845 AM CST SUN DEC 20 2015 WIDESPREAD MVFR/IFR CONDITIONS IN STRATUS AND FOG THIS MORNING WILL TREND TOWARDS IFR/LIFR THIS AFTERNOON AND THROUGH THE NIGHT ACROSS WESTERN AND CENTRAL NORTH DAKOTA. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...JV LONG TERM...JJS AVIATION...AYD
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
313 PM MST SUN DEC 20 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 126 PM MST SUN DEC 20 2015 UPPER TROF OVER WRN CO THIS AFTN WILL MAKE ITS WAY TO THE ERN CO BY 00Z WITH A WNWLY FLOW ALOFT OVERNIGHT. BEST QG ASCENT TODAY WILL THIS AFTN...WITH INCREASING QG DESCENT OVERNIGHT. IN THE MOUNTAINS TONIGHT...INCREASING STABILITY AND SUBSIDENCE WILL DEVELOP OVERNIGHT...BUT A GOOD OROGRAPHIC/MOISTURE COMPONENT PRESENT THIS EVENING...THEN LATE TNGT AND MONDAY MORNING...THE NAM12 SPATIAL CROSS SECTIONS SHOWS MOISTURE DEPTH DECREASING SIGNIFICANTLY. SNOWFALL AT THAT TIME WILL BE MINIMAL AND CONFINED PRIMARILY TO WEST FACING SLOPES. WINDY AS WELL...BUT THE MOUNTAIN WAVE IS NOT VERY AMPLIFIED SO STRONGER GUSTS SHOULD BE ABOVE TIMBERLINE OR HIGH EXPOSED EAST FACING SLOPES. FOR THE NORTHEAST PLAINS...THE HRRR CONTINUES TO GENERATE PCPN AROUND THE URBAN CORRIDOR AND PALMER DIVIDE LATE THIS AFTN AND EVENING...WL KEEP ISOLD-CHC POPS PRIMARILY EAST AND SOUTH OF DENVER THROUGH 02Z OR SO. ON MONDAY...SHORT WAVE RIDGE WITH GOOD MID LEVEL SUBSIDENCE THROUGH 18Z. SNOW DOES RETURN TO THE HIGH COUNTRY BY LATE AFTN AS THE RIDGE SHIFTS EAST AND WEAK QG ASCENT DEVELOPS AHEAD OF THE NEXT SYSTEM. SNOWFALL WILL REMAIN ON THE LIGHT SIDE...AN INCH OR LESS. IN DENVER AND THE NORTHEAST PLAINS DRY MONDAY WITH TEMPERATURES NEAR SEASONAL NORMALS. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 126 PM MST SUN DEC 20 2015 MODELS HAVE MODERATE WESTERLY FLOW ALOFT FOR THE CWA MONDAY NIGHT. ON TUESDAY A BIT OF AN UPPER TROUGH AXIS PUSHES ACROSS COLORADO PART OF A BROAD MEAN TROUGH DEVELOPING OVER A GOOD PART OF NORTH AMERICA. THIS FEATURE MOVES LITTLE SLIGHT EASTWARD AND THROUGH WEDNESDAY NIGHT. BY WEDNESDAY NIGHT...THE WESTERLY FLOW ALOFT OVER US IS QUITE STRONG WITH A 140 KNOW JET MAXIMUM GETTING INTO SOUTHWEST COLORADO BY 12Z THURSDAY MORNING. THE QG VERTICAL VELOCITY FIELDS SHOW WEAK UPWARD SYNOPTIC SCALE ENERGY MONDAY NIGHT AND TUESDAY...THEN WEAK DOWNWARD ENERGY INTO WEDNESDAY. THERE IS A BIT OF UPWARD AGAIN WEDNESDAY AFTERNOON...THEN DOWNWARD WEDNESDAY NIGHT. THE LOW LEVEL WINDS ARE NORMAL DRAINAGE PATTERNS MONDAY NIGHT. TUESDAY`S WINDS LOOK TO BE NORMAL DIURNAL PATTERNS TOO. TUESDAY NIGHT HAS SOME NORTHWESTERLY DOWNSLOPING. WEDNESDAY HAS VARIABLE DIRECTIONS DEPENDING ON THE MODEL. THEY ARE ALL OVER THE PLACE AND NOT VERY STRONG...SO NORMAL PATTERNS LOOK GOOD. DOWNSLOPING TO DRAINAGE WEDNESDAY NIGHT. FOR MOISTURE... THERE IS PLENTY OVER THE MOUNTAINS WEST OF THE DIVIDE AND RIGHT ALONG IT MUCH OF THE TIME...AT LEAST THROUGH 06Z TUESDAY NIGHT. MOISTURE DECREASES INTO WEDNESDAY MORNING...THEN INCREASES AGAIN IN THE MOUNTAINS BY AFTERNOON INTO WEDNESDAY EVENING. MOISTURE DECREASES AGAIN LATE WEDNESDAY NIGHT. THE QPF FIELDS DO SHOW MEASURABLE SNOWFALL...MAINLY IN THE MOUNTAINS. THE HIGHEST AMOUNTS OCCUR ON TUESDAY INTO TUESDAY EVENING...BUT THEY ARE STILL NOT SIGNIFICANT. CONCERNING HIGHLIGHT FOR MOUNTAIN SNOWS...THE RHEA- THALER SNOW MODEL DOES NOT YIELD WARNING AMOUNTS IN MOST AREAS. THE EXCEPTION MAY BE ZONE 31. THERE ARE 9-15 INCHES IN ZONES 31 FROM 00Z MONDAY EVENING THROUGH 12Z WEDNESDAY MORNING. THERE ARE SOME DYNAMICS...BUT NOTHING GREAT. ALSO 700 MB WINDS SPEEDS ARE NOT THAT STRONG AND DIRECTION IS NOTE EVEN DUE WESTERLY. THE DECENT SNOWFALL RATES DO NOT APPEAR TO KICK IN UNTIL 12Z TUESDAY MORNING AS WELL...SO NO HIGHLIGHTS YET. FOR TEMPERATURES...TUESDAY`S HIGHS ARE 0-2 C WARMER THAN MONDAY`S. WEDNESDAY`S HIGHS ARE 1-3 C COOLER THAN TUESDAY`S. FOR THE LATER DAYS...THURSDAY THROUGH SUNDAY...THERE IS A BROAD UPPER TROUGH OVER COLORADO THURSDAY ...WITH A STRONG WEST-SOUTHWESTERLY JET MAXIMUM ACROSS THE STATE. THE UPPER TROUGH DEEPENS TO OUT WEST OVER THE GREAT BASIN ON FRIDAY...WITH STRONG SOUTHWESTERLY FLOW ALOFT FOR THE CWA. THE UPPER TROUGH DEEPENS FRIDAY NIGHT AND SATURDAY AND MOVES EASTWARD. THE AXIS IS OVER THE CWA AT 00Z EARLY SATURDAY EVENING. NORTHERLY FLOW ALOFT IS OVER THE CWA SATURDAY NIGHT...THAN NORTHWESTERLY ON SUNDAY. THE ONLY NOTABLE COLD FRONT IS FOR FRIDAY AFTERNOON ALONG WITH SOME UPSLOPE OVER THE PLAINS THROUGH SATURDAY. WILL NEED "CHANCE"S OF SNOW 1IN THE MOUNTAINS MUCH OF THE TIME INTO SATURDAY...THEN NOTHING THROUGH SUNDAY. FOR THE PLAINS...WILL GO WITH A "SLIGHT CHANCE"S OF SNOW THURSDAY EVENING THROUGH SATURDAY. THE BEST SHOT NOW LOOKS TO BE FRIDAY NIGHT...BUT THAT WILL LIKELY CHANGE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 126 PM MST SUN DEC 20 2015 UPPER TROUGH WILL PASS TO THE EAST BY EARLY THIS EVENING. UNTIL THAT TIME...SUFFICIENT MOISTURE AND MID LEVEL INSTABILITY TO SUPPORT A FEW BRIEF RAIN/SNOW SHOWERS. COULD SEE CIGS BKN CIGS OF 6-7 KFT AGL WITH ANY SHOWERS. IMPROVING CIGS AFTER 01Z...WITH VFR CONDITIONS THE REST OF THE PERIOD. E/NELY WINDS WILL TRANSITION TO S/SELY THIS EVENING THEN SWLY BY 03Z. WINDS PRIMARILY SWLY ON MONDAY. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...COOP LONG TERM...KOOP AVIATION...COOP
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
343 PM EST SUN DEC 20 2015 .SYNOPSIS... ISSUED AT 336 PM EST SUN DEC 20 2015 RAIN WILL OVERSPREAD THE AREA TONIGHT AND CONTINUE INTO MONDAY MORNING. AFTER A BRIEF DRY PERIOD...SHOWER CHANCES WILL ARRIVE MID WEEK AND PERSIST ON AND OFF INTO THE WEEKEND. ABOVE TO WELL ABOVE NORMAL TEMPERATURES WILL DOMINATE MOST OF THE PERIOD...WITH RECORD HIGH TEMPERATURES LIKELY TO BE BROKEN WEDNESDAY. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 336 PM EST SUN DEC 20 2015 WATER VAPOR IMAGERY AND LATEST RUC ANALYSIS DEPICTING UPPER TROF OVER THE FOUR CORNERS WITH POTENT 120KT UPPER JET MOVING UP THE EAST SIDE OF THE TROF AXIS. THIS ENERGY WILL EJECT EASTWARD AND HELP ORGANIZE DEVELOPING SURFACE LOW IN THE PLAINS. DESPITE PROGRESSIVE NATURE OF THIS SYSTEM...IMPRESSIVE DYNAMICS WILL AID IN DECENT MOISTURE TRANSPORT INTO THE REGION OVERNIGHT AND SUPPORT WIDESPREAD LIGHT TO MODERATE RAIN. GOOD ISENTROPIC ASCENT AHEAD OF THIS SYSTEM WILL RAPIDLY SATURATE THE LOW LEVELS AFTER 06Z IN OUR WESTERN CWA WITH ARRIVAL OF 60KT LLJ EARLY MONDAY MORNING. WILL TREND ARRIVAL OF PRECIP IN A NW/SE ORIENTATION WITH NW CWA BECOMING LIKELY SHORTLY AROUND 06Z AND SE BY 09Z MONDAY. MODELS IN DECENT AGREEMENT WITH BRINGING WEAK DRY SLOT INTO THE AREA MONDAY AFTERNOON WHICH WILL DIMINISH...BUT NOT ELIMINATE...POPS DOWN TO CHANCE/SLIGHT CHANCE. WARM AIR ADVECTION PATTERN ON STRONG SOUTHERLY FLOW WILL LIMIT DIURNAL TEMP CHANGES DURING THE PERIOD WITH LOWS TONIGHT NEAR 40F AND HIGHS NEAR 50F OVER MOST OF THE CWA MONDAY. && .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 336 PM EST SUN DEC 20 2015 RETURN TO ABOVE TO WELL ABOVE NORMAL TEMPERATURES FOR MOST IF NOT ALL THE FORECAST PERIOD...WITH A FEW CHANCES FOR RAINFALL...ESPECIALLY MIDWEEK. LOW PRESSURE WILL BE QUICKLY EXITING TO THE NORTHEAST OF THE AREA WITH A TRAILING DISTURBANCE MOVING THROUGH THE AREA MONDAY NIGHT. SOME WEAK LIFT IS DEPICTED IN ALL MODELS IN THE LOWEST LEVELS WITH NAM THE MOST PRONOUNCED. NOT SURE ABOUT HOW MUCH OF THE PRECIP WILL BE MEASURABLE RAIN VS DRIZZLE GIVEN SHALLOW NATURE OF LIFT. WILL KEEP WITH SLGT CHC TO CHC POPS AND ADD MENTION OF PATCHY DRIZZLE THROUGH THE NIGHT. LITTLE SIGNIFICANT CHANGE IN SURFACE TEMPERATURES MON NGT INTO TUESDAY WITH ONLY A GLANCING BLOW OF SLIGHTLY COLDER BUT STILL ABOVE NORMAL) AIR. FOCUS THEN SHIFTS TO DEEP TROUGH DIGGING INTO THE CENTRAL PLAINS WHICH WILL EJECT TOWARDS THE REGION WEDNESDAY INTO WEDNESDAY NIGHT ADVECTING WARMER AND MORE HUMID AIR (PWATS 0.75 TO 1 INCH) INTO THE REGION. WITH CURRENTLY FORECASTED HIGHS OF 60 OR HIGHER...RECORD HIGH TEMPERATURES WILL BE BROKEN FOR BOTH SOUTH BEND AND FT WAYNE (59 IN 1933 AND 59 IN 1941 RESPECTIVELY). SHOWERS CHANCES WILL INCREASE FROM WEST TO EAST WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT WITH ALL LOCATIONS TO SEE AT LEAST SOME MEASURABLE RAINFALL. HEAVIEST AXIS OF RAINFALL LOOKS TO REMAIN INTO ILLINOIS. NEIGHBORS TO THE WEST AND SOUTH HAVE ADDED MENTION OF THUNDER AND WHILE NAM/GFS DO ATTEMPT BRING A NARROW RIBBON OF NEAR ZERO SHOWALTERS IN BETWEEN 00Z AND 6Z NOT CONVINCED COVERAGE (IF ANY) WILL BE ENOUGH TO WARRANT A MENTION. GIVEN THE WESTERLY TRACK OF THE LOW AND RELOADING OF AN EVEN STRONGER TROUGH IN THE WEST...NO MAJOR COLD AIR ARRIVES WITH READINGS DROPPING BACK TO THE 40S AND 50S...STILL WELL ABOVE THE NORMALS IN THE UPPER 30S AND NOT BODING WELL FOR ANY CHANCES OF A WHITE CHRISTMAS FOR THE AREA. LARGE MODEL DIFFERENCES EXIST WITH HANDLING OF CLOSED UPPER LOW AND ITS IMPACTS THIS WEEKEND. HAVE CONTINUED WITH SLGT CHC TO CHC POPS STARTING FRIDAY NIGHT AND PERSISTING THROUGH THE WEEKEND. TEMPERATURES MAY RETURN TO NEAR NORMAL LEVELS AT THE END OF THE PERIOD BUT GIVEN LARGE MODEL DIFFERENCES NOT SURE IF THIS WILL HOLD TRUE OR NOT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1230 PM EST SUN DEC 20 2015 VFR CONDITIONS TO BEGIN THE TAF PERIOD WITH HIGH CIRRUS SHIELD THIS AFTERNOON BUT WITH GUSTY SOUTH WINDS. AS GUSTY CONDITIONS DIMINISH OVERNIGHT AND LOW LEVEL JET STRENGTHENS...LLWS ANTICIPATED AT BOTH SITES WITH PEAK NEAR 60KTS AT 2KFT. RAIN EXPECTED TO DEVELOP OVERNIGHT INTO EARLY MONDAY MORNING AHEAD OF APPROACHING LOW PRESSURE SYSTEM AND WILL BRING IFR CONDITIONS ON MONDAY...GOOD CHANCE AT EVEN DROPPING TO LIFR BUT NEAR THE END OF TAF PERIOD SO WILL HOLD OFF FOR NOW. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST MONDAY FOR LMZ043-046. && $$ SYNOPSIS...FISHER SHORT TERM...JAL LONG TERM...FISHER AVIATION...LOGSDON VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1143 AM CST SUN DEC 20 2015 ...Update to aviation forecast discussion... .SHORT TERM...(Today and Tonight) Issued at 257 AM CST SUN DEC 20 2015 Winds already picking up in the early morning hours, with winds aloft forecast to increase and stay up through the day today. This has kept overnight lows up in the 40s most areas. As the boundary layer mixes out this morning, RAP and GFS suggest winds at the top of the mixed layer are close to 50 kts. As a result, expect high temperatures to make it into the middle/upper50s, and wind speeds to gust near wind advisory criteria of 40 kts. Will hoist a wind advisory for those counties along and south of I-70. Still a chance for some light drizzle and light rain to develop late this morning in the WAA regime, followed by precip chances continuing due to the shortwave trof moving eastward out of the high plains later this evening. These showers could also aid in mixing down some of the stronger wind speeds through the day today. Both GFS and NAM indicating just a few hours with some weak instability in the column in the midnight to 3am timeframe as the stronger lift and cold pool aloft move over the eastern part of the state. Have left thunder out at this time given small window, but is worth mentioning here. As trof moves eastward, cooler air moves in behind and lows fall into he 20s to middle 30s. .LONG TERM...(Monday through Saturday) Issued at 257 AM CST SUN DEC 20 2015 On Monday another mid level trough tracks over the central US, which should not have much effect on the overall weather. Highs will be cooler in the mid to upper 40s. On Tuesday return flow quickly develops as yet another shortwave approaches from the west, which will allow temperatures to warm back into the 50s. This shortwave trough appears to deepen Tuesday night as it passes over the forecast area. Increased moisture and lift as well as an advancing cold front could support rain Wednesday morning and into the afternoon. This precip appears to stay confined to portions of eastern KS. Towards the end of the week a few of the models continue to bring out weak shortwaves that could cause light precip, but confidence in timing and location is low at this point. Models continue to show a strong system over the southern Rockies over the weekend, but also continue to struggle on how to evolve that system. && .AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon) Issued at 1132 AM CST SUN DEC 20 2015 Somewhat of a complicated forecast for the next 18-24hrs. Gusty southerly winds continue through the afternoon. Expecting winds to continue to be brisk this evening before the system to the west of the terminals pushes through. There is a chance for some very isolated thunderstorm activity to develop for a period tonight as the upper low advances into the region. Have reflected this as VCTS at the KTOP/KFOE terminals. A general lack of instability further west doesn`t seem to support the same setup near KMHK. Winds change to the West/northwest by Monday morning. && .TOP Watches/Warnings/Advisories... Wind Advisory until 6 PM CST this evening for KSZ035>040-054>056- 058-059. && $$ SHORT TERM...67 LONG TERM...Sanders AVIATION...Drake
AREA FORECAST DISCUSSION
NWS JACKSON KY
1234 PM EST SUN DEC 20 2015 .UPDATE... ISSUED AT 1102 AM EST SUN DEC 20 2015 TEMPERATURES HAVE BEGUN TO RISE ACROSS THE AREA THIS MORNING...THOUGH SLOWLY DUE TO INCREASING UPPER LEVEL CLOUD COVER. HAVE ADJUSTED TEMPS AND CLOUD COVER WITH THIS UPDATE. UPDATE ISSUED AT 640 AM EST SUN DEC 20 2015 A BAND OF CIRRUS SLIPPED OVER THE CWA DURING THE PAST COUPLE OF HOURS AND THEY LIKELY HELPED TO SLOW THE TEMPERATURE DROP IN THE VALLEYS AND ELSEWHERE. ACCORDINGLY...HAVE TWEAKED THE SKY COVER AND T/TD GRIDS PER THE LATEST OBS AND TRENDS. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 345 AM EST SUN DEC 20 2015 07Z SFC ANALYSIS SHOWS HIGH PRESSURE STARTING TO SLIP OFF TO THE EAST. BEFORE IT GOES IT IS GIVING THE AREA ONE MORE CHILLY NIGHT ALONG WITH A DECENT SIZED RIDGE TO VALLEY TEMPERATURE SPLIT. CLEAR SKIES BENEATH THE HIGH ALONG WITH LIGHT SFC WINDS AND A DRY AIR MASS HAS RESULTED IN VALLEY TEMPERATURES HAVEN FALLEN TO NEAR 20 DEGREES. MEANWHILE...THE RIDGES ARE CLOSER TO FREEZING WHILE DEWPOINTS THROUGHOUT THE AREA ARE CROWDING THE 20 DEGREE MARKER. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST. THEY ALL DEPICT A FLAT RIDGE CROSSING THE TENNESSEE VALLEY WITH HEIGHT RISES ON TAP FOR KENTUCKY TODAY. A SHORTWAVE TROUGH WILL THEN MOVE INTO THE SOUTHERN PLAINS TONIGHT PLACING OUR AREA DOWNSTREAM IN BROAD SOUTHWEST FLOW. SOME WEAK ENERGY WAVES WILL PASS THROUGH EASTERN KENTUCKY BY MONDAY MORNING WITH THE MAIN WAVE TAKING A TRACK TO THE NORTHWEST OF KENTUCKY. SOUTHWEST FLOW WILL CONTINUE INTO MONDAY EVENING AS ANOTHER TROUGH AND ENERGY BATCH HEAD FOR THE STATE FROM THE WEST. GIVEN THE GENERAL MODEL AGREEMENT HAVE AGAIN FAVORED THE HIGHER RESOLUTION HRRR AND NAM12 FOR WEATHER DETAILS. SENSIBLE WEATHER WILL FEATURE ANOTHER CHILLY START THIS MORNING... BUT PLENTY OF SUNSHINE WILL OVERCOME THAT YIELDING AFTERNOON TEMPERATURES IN THE 50 TO 55 DEGREE RANGE. HIGH CLOUDS WILL ARRIVE AND THICKEN WITH TIME THIS AFTERNOON INTO THE NIGHT AHEAD OF A QUICK MOVING COLD FRONT INBOUND FROM THE WEST. THIS FRONT WILL BRING ANOTHER ROUND OF SHOWERS TO THE CWA FOR MONDAY...THOUGH THE BEST MOISTURE AND HIGHEST PCPN CHANCES SPLIT THE AREA TO THE NORTH AND SOUTH. WHILE SOME EASTERN VALLEYS WILL FALL BELOW FREEZING TONIGHT...EXPECT THE FRONT/S APPROACH TO STIR THE AIR ENOUGH TO KEEP THEM FROM BEING THAT COLD WHEN THE FIRST RAIN CHANCES ARRIVE...SO HAVE LEFT ANY MIX CHANCES OF PCPN OUT OF THE FORECAST FOR NOW. THE FRONT WILL THEN STALL OVERHEAD THAT WITH THE NEXT SURGE OF MOISTURE LIKELY RIDING NORTH INTO THIS PART OF THE STATE LATER MONDAY NIGHT. FOR TEMPERATURES AND DEWPOINTS...HAVE AGAIN STARTED WITH THE SHORTBLEND GRIDS THROUGH TONIGHT FOLLOWED BY THE SUPERBLEND INTO MONDAY EVENING. DID AGAIN MAKE SOME MORE SIGNIFICANT ADJUSTMENTS TO THE LOWS TONIGHT...ESPECIALLY IN THE EASTERN VALLEYS DUE TO THE ANTICIPATION OF AN EARLY TEMPERATURE DROP OFF THIS EVENING FOLLOWED BY RISING TEMPS TOWARD DAWN FOR THE MOST SHELTERED LOCATIONS. AS FOR POPS...ENDED UP ON THE HIGHER SIDE OF ALL MOS FOR MONDAY...BUT CLOSEST TO THE MAV NUMBERS. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 315 AM EST SUN DEC 20 2015 VERY MILD AND POTENTIALLY RECORD BREAKING WARMTH WILL REMAIN THE MAIN HEADLINE AS WE HEAD THROUGH CHRISTMAS WEEK. IN ADDITION TO THE WARMTH...PLENTY OF CHANCES FOR RAIN WILL BE SEEN. STRONG RIDGING WILL BE IN PLACE ACROSS THE EASTERN CONUS THROUGH ALL OF CHRISTMAS WEEK. STARTING OFF TUESDAY NIGHT...A POTENT SHORTWAVE WILL MOVE NORTHEAST ACROSS THE OHIO RIVER VALLEY ALONG A STALLED OUT COLD FRONT. THIS WILL BRING INCREASING RAIN CHANCES THROUGH THE OVERNIGHT HOURS. FORCING WITH THIS WAVE WILL EXIT NORTH EARLY TUESDAY MORNING...WITH SUBSIDENCE BUILDING IN BEHIND THE DEPARTING WAVE ON TUESDAY. TEMPERATURES WILL CLIMB INTO THE 60S ON TUESDAY ALTHOUGH WE`LL HAVE A TOUGH TIME GETTING RID OF THE CLOUDS. A SECONDARY WAVE WILL LIFT NORTH TUESDAY NIGHT AND BRING ANOTHER ROUND OF RAIN SHOWERS TO EASTERN KENTUCKY. STILL SOME UNCERTAINTY ON THE EXTENT OF RAIN CHANCES AND HOW SOUTHEAST DOWNSLOPING FLOW IMPACTS OUR RAIN CHANCES. HOWEVER...WILL GO WITH HIGHEST POPS IN THE WEST...TO LOWER POPS IN THE EAST. ON WEDNESDAY...WE MAY SEE ANOTHER LULL AS SUBSIDENCE SPREADS BACK IN BEHIND THE DEPARTING WAVE. WITH EVEN WARMER BOUNDARY LAYER CONDITIONS IN PLACE...WE COULD BE EASILY PUSHING 70...WITH GUIDANCE SUGGESTING WIDESPREAD LOWER 70S. THIS WOULD EXCEED OUR RECORDS FOR WEDNESDAY BY 5 TO 8 DEGREES. FINALLY...A COLD FRONT WILL WORK EAST ACROSS THE AREA WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING...BRINGING ANOTHER SURGE OF RAIN. THIS TIME AROUND...THE FRONT SHOULD MOVE ON EAST...BRINGING A TEMPORARY END TO THE RAIN CHANCES. HIGH PRESSURE SHOULD KEEP THE WEATHER DRY FROM LATE THURSDAY MORNING THROUGH CHRISTMAS MORNING. HOWEVER...MODELS ARE TRENDING FASTER WITH BRINGING RAIN CHANCES. IF THIS OCCURS...WE WILL CERTAINLY BRING POPS BACK INTO THE AREA ON CHRISTMAS AS A WARM FRONT QUICKLY SURGES BACK TO THE NORTH. THIS WILL NOT ONLY MEAN A WARMER CHRISTMAS...BUT A WETTER ONE AS WELL. AS WE HEAD INTO THE WEEKEND...MODELS ARE HAVING A TOUGH TIME ON HOW THINGS EVOLVE...BUT CERTAINLY COULD BE SOME WET WEATHER AT SOME POINT OVER THE WEEKEND AS A DEEP SYSTEM ORGANIZES SOMEWHERE OVER THE CENTRAL OR EASTERN US. FOR THIS REASON WILL KEEP SOME CHANCE POPS IN THE FORECAST THROUGH THE WEEKEND. IT DOES LOOK LIKE WE SHOULD REMAIN MILD THROUGH THE WEEKEND...WITH PERHAPS A BRIEF COOL DOWN AS WE HEAD INTO THE FOLLOW WEEK. HOWEVER...THERE IS MUCH UNCERTAINTY IN THE FORECAST BEYOND CHRISTMAS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1234 PM EST SUN DEC 20 2015 HIGH PRESSURE WILL REMAIN IN CONTROL ACROSS THE REGION THROUGH MUCH OF THE TAF PERIOD PROVIDING VFR CONDITIONS UNDER THICKENING HIGH CLOUDS. AN APPROACHING COLD FRONT WILL BRING IN A DECK OF MID LEVEL CLOUD TOWARD DAWN ON MONDAY. BY 14Z ON MONDAY...SOME LOCATIONS WILL SEE SHOWERS MOVING INTO THE AREA WITH SOME MVFR CIGS DEVELOPING TOWARDS THE END OF THE TAF PERIOD. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE BULK OF THE PERIOD BEFORE INCREASING AND GUSTING UP TO 20 KNOTS OUT OF THE SOUTH BY LATE MONDAY MORNING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SHALLENBERGER SHORT TERM...GREIF LONG TERM...KAS AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
1201 PM MST SUN DEC 20 2015 .UPDATE... FOG HAS BURN OFF ACROSS MOST OF THE AREA. THERE MAY BE A FEW PATCHES OF FOG BUT NOTHING WIDESPREAD. WITH VISIBILITIES RECOVERING HAVE CANCELLED THE DENSE FOG ADVISORY. REIMER && .SHORT TERM...VALID FOR TDY AND MON... A VERY PROGRESSIVE PATTERN WILL BE OVER SOUTHERN MONTANA AND NORTHERN WYOMING THROUGH THE EARLY PART OF THE WEEK. THE FAST MOVING NATURE OF THE ENERGY AND LACK OF AN AMPLIFIED PATTERN WILL PREVENT A STRONG SURGE OF ARCTIC AIR AND THE DEVELOPMENT OF A LARGE SNOW PRODUCING SYSTEM. A COUPLE OF DIFFERENT SYSTEMS WILL WORK THROUGH AND PRODUCE AREAS OF SNOW SHOWERS...BUT THE SYSTEMS WILL BE FAST MOVING AND THIS IN TURN WILL KEEP SNOW ACCUMULATIONS DOWN. THE MOST LIKELY LOCATION TO SEE ACCUMULATING SNOW WILL BE THE SOUTHWEST MOUNTAINS WITH A STEADY STREAM OF MOISTURE FEEDING INTO THE WESTERN SLOPES. ONE SYSTEM MOVED ACROSS CENTRAL ZONES OVERNIGHT AND WILL SLIDE ACROSS SOUTHERN MONTANA THIS MORNING. THIS ENERGY IS PROGGED TO WEAKEN AS IT PROGRESSES EASTWARD...SO SNOW SHOWER ACTIVITY ASSOCIATED WITH IT WILL BE LESS DYNAMIC THAN IT WAS OVER WESTERN AND CENTRAL ZONES OVERNIGHT. WILL LINGER LOW POPS OVER THE SOUTHERN HALF OF THE AREA THIS MORNING. AREAS OF FOG FORMED BEHIND THE BAND OF LIGHT TO MODERATE SNOW THAT WORKED THROUGH OVERNIGHT. HI RESOLUTION MODELS INDICATE THAT SOME LOW CEILINGS AND FOG WILL PERSIST OVER PARTS OF THE MORNING. RAP SOUNDINGS KEEP LOW CLOUDS AND SOME FOG IN BILLINGS THROUGH 16Z...THEN LIFT IT OUT AS STRONGER MIXING WINDS FORM IN THE LOWER LEVELS WITH A LEE TROUGH FORMING. ADDED AREAS OF FOG FOR PARTS OF THE AREA FOR THE MORNING. THE NEXT SHORTWAVE TO ADVANCE THROUGH THE AREA WILL BE SUNDAY NIGHT AND EARLY MONDAY. THIS SYSTEM DOES PACK SOME INSTABILITY WITH LAPSE RATES OF AROUND 8C/KM FROM 850-500MB. THE MAIN CORE OF THE WAVE RIDES ACROSS NORTHERN MONTANA...WHICH IS NOT IN A GOOD LOCATION FOR PRECIPITATION CHANCES. HAVE BRUSHED SOME LOW POPS IN DUE TO INSTABILITY AND OVERALL STRENGTH OF THE SHORTWAVE TROUGH. MAY NEED TO RAISE POPS IN FUTURE UPDATES IF THE CORE TRACKS A LITTLE FARTHER SOUTH. YET ANOTHER WAVE WORKS IN MONDAY NIGHT INTO TUESDAY MORNING FOR A CHANCE OF SNOW SHOWERS. THIS SYSTEM WAS TRACKING A LITTLE FARTHER SOUTH THUS MAY HAVE A BETTER CHANCE OF PRODUCING SNOW SHOWERS FOR THE FORECAST AREA. TEMPERATURES THE NEXT COUPLE OF DAY SHOULD BE RIGHT AROUND SEASONAL AVERAGES. TWH .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... EXTENDED MODELS WERE IN OVERALL AGREEMENT THROUGH THE PERIOD IN SHOWING A PROGRESSIVE WESTERLY FLOW WITH MULTIPLE WAVES MOVING THROUGH THE FLOW. MODELS CONTINUE TO BRING A SPLITTING TROUGH INTO THE REGION THU NIGHT THROUGH FRI NIGHT. THE MODELS HANDLE THIS FEATURE DIFFERENTLY INTO SAT. THE GFS AND ECMWF SHOW MOISTURE OVER THE AREA IN W FLOW THU NIGHT THEN DRY OUT THE MOISTURE ON FRI/FRI NIGHT. ECMWF HINTS AT TRYING TO BRING WRAP-AROUND MOISTURE FROM A 700 MB LOW INTO THE SE BY SAT MORNING. THESE PERIODS APPEAR TO BE IN FLUX BASED ON HOW THE MODELS LOOKED LAST NIGHT...SO TO FOLLOW TRENDS...JUST HAVE LOW POPS OVER PORTIONS OF THE AREA THROUGH FRI NIGHT. ANOTHER DIFFERENCE WITH THESE NEW MODEL RUNS IS HOW THE PRESSURE GRADIENT SETS UP QUITE STRONGLY OVER THE AREA ON SAT AND CONTINUES INTO SUN WITH SOME DIFFERENCES BETWEEN THE MODELS ON HOW THE GRADIENT SETS UP. BASED ON THE GRADIENT STRENGTH...HAVE INCREASED GAP FLOW WINDS INTO THE ADVISORY/WARNING CRITERIA WIND SPEEDS DURING THIS TIME FRAME. WILL DEFINITELY NEED TO WATCH MODEL TRENDS TO SEE IF THIS PATTERN PERSISTS FROM RUN-TO-RUN. OTHERWISE...MODELS BRING A SHORTWAVE THROUGH THE AREA ON TUE WITH MORE ENERGY ON WED. WEAKER ENERGY FOLLOWS ON THU. NEAR-NORMAL TEMPERATURES WILL CONTINUE WITH CHANCES FOR SNOW EACH PERIOD...ESPECIALLY IN THE MOUNTAINS. FRI WILL BE THE COLDEST DAY WITH 850 MB TEMPERATURES AROUND -8 DEGREES C...THEN TEMPERATURES WILL MODERATE THROUGH THE WEEKEND. ARTHUR && .AVIATION... VLIFR CONDITIONS ARE EXPECTED TO PERSIST AT KBIL UNTIL AROUND NOON... DEPENDING ON WHEN HIGH CLOUDS CLEAR OUT. AFTERWARD... CONDITIONS WILL IMPROVE TO MVFR OR BETTER. THE FOG MAY RETURN TONIGHT BUT CONFIDENCE IN THIS OCCURRING IS NOT VERY HIGH AT THIS TIME. IFR TO VLIFR CONDITIONS DUE TO FOG OVER KMLS WILL CONTINUE THIS MORNING AND POSSIBLY THROUGH THE PERIOD. MVFR CONDITIONS HAVE ENDED IN KSHR... WITH VFR EXPECTED TO CONTINUE INTO TONIGHT. OTHERWISE VFR SHOULD PREVAIL ACROSS OUR AREA THROUGH TONIGHT. THE BEARTOOTHS/ABSAROKAS AND NE BIG HORNS WILL BE MOSTLY OBSCURED TODAY AND WILL CONTINUE TONIGHT FOR THE BEARTOOTHS/ABSAROKAS. MROWELL && .PRELIMINARY POINT TEMP/POPS... TDY MON TUE WED THU FRI SAT ------------------------------------------------------- BIL 033 021/034 021/035 020/031 015/027 007/022 009/028 1/B 21/N 22/J 23/J 21/E 11/B 11/N LVM 035 021/032 022/034 019/028 016/027 006/021 009/026 2/S 32/S 43/J 43/J 22/J 22/J 11/N HDN 034 018/036 017/036 014/034 009/028 002/020 000/027 1/B 21/B 22/W 23/J 21/E 11/B 11/U MLS 032 020/035 016/033 014/029 010/026 005/023 005/026 1/B 12/S 12/J 23/J 21/E 11/E 11/U 4BQ 033 019/036 017/035 015/029 008/027 005/023 008/027 2/S 12/S 11/E 23/J 21/E 11/E 11/U BHK 031 019/034 017/033 015/027 013/027 008/023 009/029 1/B 02/S 01/E 32/J 21/E 11/E 11/B SHR 033 017/035 017/036 014/029 008/027 004/023 004/029 3/S 12/S 22/J 23/J 21/B 12/J 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
925 AM MST SUN DEC 20 2015 .UPDATE... FOG CONTINUES TO LINGER ACROSS SOUTHEASTERN MONTANA AND INTO BILLINGS...WITH VISIBILITIES REMAINING AROUND A QUARTER MILE AT MANY LOCATIONS. THE TRENDS IN THE HRRR VISIBILITIES AND LOW LEVEL HUMIDITY VALUES CONTINUE THE LOWER VISIBILITIES INTO THE AFTERNOON. HAVE GONE WITH A DENSE FOG ADVISORY THROUGH 3 PM. THINGS SHOULD BEGIN IMPROVING AROUND BILLINGS BY NOON...AND SLOWLY IMPROVE EASTWARD THROUGH THE AFTERNOON. GIVEN THE THE SUN ANGLE IS AT ITS LOWEST AND WINDS WILL REMAIN LIGHT...IT WILL BE A STRUGGLE TO BURN OFF ALL OF THE FOG ESPECIALLY FROM MILES CITY EASTWARD. REIMER && .SHORT TERM...VALID FOR TDY AND MON... A VERY PROGRESSIVE PATTERN WILL BE OVER SOUTHERN MONTANA AND NORTHERN WYOMING THROUGH THE EARLY PART OF THE WEEK. THE FAST MOVING NATURE OF THE ENERGY AND LACK OF AN AMPLIFIED PATTERN WILL PREVENT A STRONG SURGE OF ARCTIC AIR AND THE DEVELOPMENT OF A LARGE SNOW PRODUCING SYSTEM. A COUPLE OF DIFFERENT SYSTEMS WILL WORK THROUGH AND PRODUCE AREAS OF SNOW SHOWERS...BUT THE SYSTEMS WILL BE FAST MOVING AND THIS IN TURN WILL KEEP SNOW ACCUMULATIONS DOWN. THE MOST LIKELY LOCATION TO SEE ACCUMULATING SNOW WILL BE THE SOUTHWEST MOUNTAINS WITH A STEADY STREAM OF MOISTURE FEEDING INTO THE WESTERN SLOPES. ONE SYSTEM MOVED ACROSS CENTRAL ZONES OVERNIGHT AND WILL SLIDE ACROSS SOUTHERN MONTANA THIS MORNING. THIS ENERGY IS PROGGED TO WEAKEN AS IT PROGRESSES EASTWARD...SO SNOW SHOWER ACTIVITY ASSOCIATED WITH IT WILL BE LESS DYNAMIC THAN IT WAS OVER WESTERN AND CENTRAL ZONES OVERNIGHT. WILL LINGER LOW POPS OVER THE SOUTHERN HALF OF THE AREA THIS MORNING. AREAS OF FOG FORMED BEHIND THE BAND OF LIGHT TO MODERATE SNOW THAT WORKED THROUGH OVERNIGHT. HI RESOLUTION MODELS INDICATE THAT SOME LOW CEILINGS AND FOG WILL PERSIST OVER PARTS OF THE MORNING. RAP SOUNDINGS KEEP LOW CLOUDS AND SOME FOG IN BILLINGS THROUGH 16Z...THEN LIFT IT OUT AS STRONGER MIXING WINDS FORM IN THE LOWER LEVELS WITH A LEE TROUGH FORMING. ADDED AREAS OF FOG FOR PARTS OF THE AREA FOR THE MORNING. THE NEXT SHORTWAVE TO ADVANCE THROUGH THE AREA WILL BE SUNDAY NIGHT AND EARLY MONDAY. THIS SYSTEM DOES PACK SOME INSTABILITY WITH LAPSE RATES OF AROUND 8C/KM FROM 850-500MB. THE MAIN CORE OF THE WAVE RIDES ACROSS NORTHERN MONTANA...WHICH IS NOT IN A GOOD LOCATION FOR PRECIPITATION CHANCES. HAVE BRUSHED SOME LOW POPS IN DUE TO INSTABILITY AND OVERALL STRENGTH OF THE SHORTWAVE TROUGH. MAY NEED TO RAISE POPS IN FUTURE UPDATES IF THE CORE TRACKS A LITTLE FARTHER SOUTH. YET ANOTHER WAVE WORKS IN MONDAY NIGHT INTO TUESDAY MORNING FOR A CHANCE OF SNOW SHOWERS. THIS SYSTEM WAS TRACKING A LITTLE FARTHER SOUTH THUS MAY HAVE A BETTER CHANCE OF PRODUCING SNOW SHOWERS FOR THE FORECAST AREA. TEMPERATURES THE NEXT COUPLE OF DAY SHOULD BE RIGHT AROUND SEASONAL AVERAGES. TWH .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... EXTENDED MODELS WERE IN OVERALL AGREEMENT THROUGH THE PERIOD IN SHOWING A PROGRESSIVE WESTERLY FLOW WITH MULTIPLE WAVES MOVING THROUGH THE FLOW. MODELS CONTINUE TO BRING A SPLITTING TROUGH INTO THE REGION THU NIGHT THROUGH FRI NIGHT. THE MODELS HANDLE THIS FEATURE DIFFERENTLY INTO SAT. THE GFS AND ECMWF SHOW MOISTURE OVER THE AREA IN W FLOW THU NIGHT THEN DRY OUT THE MOISTURE ON FRI/FRI NIGHT. ECMWF HINTS AT TRYING TO BRING WRAP-AROUND MOISTURE FROM A 700 MB LOW INTO THE SE BY SAT MORNING. THESE PERIODS APPEAR TO BE IN FLUX BASED ON HOW THE MODELS LOOKED LAST NIGHT...SO TO FOLLOW TRENDS...JUST HAVE LOW POPS OVER PORTIONS OF THE AREA THROUGH FRI NIGHT. ANOTHER DIFFERENCE WITH THESE NEW MODEL RUNS IS HOW THE PRESSURE GRADIENT SETS UP QUITE STRONGLY OVER THE AREA ON SAT AND CONTINUES INTO SUN WITH SOME DIFFERENCES BETWEEN THE MODELS ON HOW THE GRADIENT SETS UP. BASED ON THE GRADIENT STRENGTH...HAVE INCREASED GAP FLOW WINDS INTO THE ADVISORY/WARNING CRITERIA WIND SPEEDS DURING THIS TIME FRAME. WILL DEFINITELY NEED TO WATCH MODEL TRENDS TO SEE IF THIS PATTERN PERSISTS FROM RUN-TO-RUN. OTHERWISE...MODELS BRING A SHORTWAVE THROUGH THE AREA ON TUE WITH MORE ENERGY ON WED. WEAKER ENERGY FOLLOWS ON THU. NEAR-NORMAL TEMPERATURES WILL CONTINUE WITH CHANCES FOR SNOW EACH PERIOD...ESPECIALLY IN THE MOUNTAINS. FRI WILL BE THE COLDEST DAY WITH 850 MB TEMPERATURES AROUND -8 DEGREES C...THEN TEMPERATURES WILL MODERATE THROUGH THE WEEKEND. ARTHUR && .AVIATION... VLIFR CONDITIONS ARE EXPECTED TO PERSIST AT KBIL UNTIL AROUND NOON... DEPENDING ON WHEN HIGH CLOUDS CLEAR OUT. AFTERWARD... CONDITIONS WILL IMPROVE TO MVFR OR BETTER. THE FOG MAY RETURN TONIGHT BUT CONFIDENCE IN THIS OCCURRING IS NOT VERY HIGH AT THIS TIME. IFR TO VLIFR CONDITIONS DUE TO FOG OVER KMLS WILL CONTINUE THIS MORNING AND POSSIBLY THROUGH THE PERIOD. MVFR CONDITIONS HAVE ENDED IN KSHR... WITH VFR EXPECTED TO CONTINUE INTO TONIGHT. OTHERWISE VFR SHOULD PREVAIL ACROSS OUR AREA THROUGH TONIGHT. THE BEARTOOTHS/ABSAROKAS AND NE BIG HORNS WILL BE MOSTLY OBSCURED TODAY AND WILL CONTINUE TONIGHT FOR THE BEARTOOTHS/ABSAROKAS. MROWELL && .PRELIMINARY POINT TEMP/POPS... TDY MON TUE WED THU FRI SAT ------------------------------------------------------- BIL 033 021/034 021/035 020/031 015/027 007/022 009/028 2/S 21/N 22/J 23/J 21/E 11/B 11/N LVM 035 021/032 022/034 019/028 016/027 006/021 009/026 2/S 32/S 43/J 43/J 22/J 22/J 11/N HDN 034 018/036 017/036 014/034 009/028 002/020 000/027 2/S 21/B 22/W 23/J 21/E 11/B 11/U MLS 032 020/035 016/033 014/029 010/026 005/023 005/026 1/B 12/S 12/J 23/J 21/E 11/E 11/U 4BQ 033 019/036 017/035 015/029 008/027 005/023 008/027 2/S 12/S 11/E 23/J 21/E 11/E 11/U BHK 031 019/034 017/033 015/027 013/027 008/023 009/029 1/E 02/S 01/E 32/J 21/E 11/E 11/B SHR 033 017/035 017/036 014/029 008/027 004/023 004/029 3/S 12/S 22/J 23/J 21/B 12/J 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...DENSE FOG ADVISORY IN EFFECT UNTIL 3 PM MST THIS AFTERNOON FOR ZONES 30>33-35-37. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1249 PM CST SUN DEC 20 2015 .UPDATE... ISSUED AT 1241 PM CST SUN DEC 20 2015 EXTENDED THE DENSE FOG ADVISORY THROUGH 00 UTC ACROSS NORTHWEST NORTH DAKOTA PER OBSERVATIONAL TRENDS THROUGH 18 UTC AND THE 16-17 UTC HRRR ITERATION VISIBILITY FORECASTS. CERTAINLY POSSIBLE THAT THE ADVISORY MAY NEED TO BE EXPANDED IN TIME AND OR AREA THROUGH THE EVENING AND OVERNIGHT AS CURRENT STRATUS ACROSS WESTERN AND CENTRAL NORTH DAKOTA IS EXPECTED TO BUILD DOWN POTENTIALLY INTO FOG. UPDATE ISSUED AT 915 AM CST SUN DEC 20 2015 QUICK UPDATE TO ISSUE A DENSE FOG ADVISORY FOR NORTHWEST NORTH DAKOTA THROUGH 19 UTC GIVEN WEBCAM AND SURFACE OBSERVATION TRENDS THROUGH 15 UTC...AND A NEAR MINIMUM SOLAR ANGLE LIMITING INSOLATION TO LIFT THE FOG POST SUNRISE. UPDATE ISSUED AT 845 AM CST SUN DEC 20 2015 OVER THE PAST TWO HOURS THROUGH 1445 UTC...VISIBILITY HAS CONTINUED TO DECREASE IN FOG ACROSS WESTERN NORTH DAKOTA PER WEBCAM AND SURFACE OBSERVATIONS...WITH LOCALLY DENSE FOG IN SOME AREAS. WILL CONTINUE TO MONITOR TRENDS THIS MORNING SHOULD A DENSE FOG ADVISORY BECOME NECESSARY...AS THE 12-13 UTC HRRR AND 06 UTC NAM NEST SUGGEST FOG MAY CONTINUE TO EXPAND THROUGH THE MORNING. UPDATE ISSUED AT 609 AM CST SUN DEC 20 2015 SOME LIGHT SNOW HAS DEVELOPED STRETCHING FROM SOUTHWEST TOWARDS THE NORTHEAST ACROSS THE STATE WHICH HIGH-RES MODELS ARE NOT PICKING UP TO WELL. FOR MORNING UPDATES HAVE ADDED POPS TO THE FORECAST TO ADDRESS THIS. EXPECT THIS SNOW TO DIMINISH BY MID-DAY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM CST SUN DEC 20 2015 MAIN CHALLENGE IN THE SHORT TERM IS CLOUD COVER AND FOG POTENTIAL. CURRENTLY...AT THE SURFACE...COOL HIGH PRESSURE WAS CENTERED OVER HUDSON BAY WITH A RIDGE AXIS EXTENDING SOUTHWEST INTO SASKATCHEWAN. THE BOUNDARY BETWEEN THIS COOL HIGH PRESSURE AND MILDER AIR TO THE SOUTH WAS A WEAK LOW PRESSURE FRONT ACROSS FAR SOUTHERN SASKATCHEWAN. AT UPPER LEVELS...A LONGWAVE TROUGH EXTENDED OVER THE EASTERN ROCKIES AND WAS POISED TO EMERGE INTO THE FRONT RANGE. THE UPPER LEVEL TROUGH IS FORECAST TO MOVE EAST ACROSS THE DAKOTAS TODAY AND TONIGHT...BUT THE BASE OF THE TROUGH IS FORECAST TO DEEPEN NEAR THE 4-CORNERS AREA TODAY AND DEVELOP A STRONGER SHORTWAVE. THIS WILL WEAKEN THE TROUGHING FARTHER NORTH AND KEEP ANY FORCING FARTHER TO THE SOUTH OF NORTH DAKOTA TODAY. MEANWHILE THE SURFACE BOUNDARY IN SOUTHERN SASKATCHEWAN IS FORECAST TO DROP SOUTH ACROSS THE STATE THIS MORNING...BRINGING WITH IT THE COOLER AND MOIST AIR OF THE CANADIAN HIGH. SKIES SHOULD REMAIN CLOUDY OVER THE STATE WITH SOME PATCHY FOG THIS MORNING. THE AXIS OF THE SURFACE HIGH IS FORECAST TO MOVE SOUTHEAST AND EXTEND FROM MANITOBA ACROSS THE EASTERN DAKOTAS BY EVENING...WITH THE COOL HIGH PRESSURE RIDGE AXIS REMAINING OVER THE EASTERN DAKOTAS SUNDAY NIGHT. WHILE CLOUDS MAY DECREASE A BIT IN THE WEST THIS AFTERNOON...CLOUDS WILL LIKELY INCREASE IN THE WESTERN PART OF THE STATE TONIGHT AS THE COOL HIGH PRESSURE MOVES EAST AND A DEVELOPING TROUGH IN THE FRONT RANGE BRINGS SOME WARM ADVECTION AND VERTICAL MOTION TO WESTERN NORTH DAKOTA. HIGHS TODAY ARE EXPECTED TO BE IN THE TEENS TO LOWER 20S OVER NORTHERN AND CENTRAL PARTS OF THE STATE...WITH UPPER 20S AND LOWER 30S IN THE SOUTHWEST. MINIMUM TEMPERATURES SUNDAY NIGHT SHOULD RANGE FROM 5 TO 10 ABOVE OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA - CLOSER TO THE COOL RIDGE AXIS - TO THE TEENS IN THE WEST. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 323 AM CST SUN DEC 20 2015 HIGHLIGHT FOR THE EXTENDED PERIOD WILL BE THE OCCASIONAL SNOW CHANCES AS VARIOUS SHORT WAVES SLIDE THROUGH THE AREA WHILE TEMPERATURES REMAIN SEASONAL. ON MONDAY...FAST MOVING SHORT WAVE ZIPS THROUGH THE AREA BRINGING CHANCES FOR LIGHT SNOW AS IT MOVES THROUGH. ANY ACCUMULATIONS WILL BE MINIMAL. FOR TUESDAY...A STRONGER SHORT WAVE PUSHES INTO THE REGION AS A SURFACE LOW LIFTS THROUGH THE DAKOTAS. THIS WILL BRING INCREASING SNOW CHANCES OVER NORTHERN AND EASTERN LOCATIONS...WITH THE GREATEST CHANCES OVER NORTH CENTRAL NORTH DAKOTA WHERE AN INCH OR TWO OF NEW SNOW WILL BE POSSIBLE. LOW CHANCES FOR SNOW LINGER INTO WEDNESDAY. MAINLY QUIET WEATHER EXPECTED ON THURSDAY. GOING INTO THE HOLIDAY WEEKEND...MODELS HAVE SHIFTED SNOW CHANCES ON FRIDAY AND SATURDAY TO THE SOUTHEAST THOUGH ARE HAVING TROUBLE COMING TO A CONSENSUS ON SOME KEY FEATURES. WITH THAT SAID...WILL RETAIN SOME LOWER SNOW CHANCES MAINLY OVER SOUTHERN AND EASTERN LOCATIONS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1241 PM CST SUN DEC 20 2015 WIDESPREAD MVFR/IFR CONDITIONS IN STRATUS EARLY THIS AFTERNOON WILL TREND TOWARDS IFR/LIFR THIS EVENING AND OVERNIGHT IN STRATUS AND FOG. PATCHY FREEZING DRIZZLE MAY BE POSSIBLE. && .BIS WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ001-002- 009-010. && $$ UPDATE...AYD SHORT TERM...JV LONG TERM...JJS AVIATION...AYD
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
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