BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, DECEMBER 8, 2016   MOSTLY CLOUDY SKIES AND LIGHT WINDS Thin radiation fog was trapped beneath a temperature inversion this morning.  Distant fog limited visibility to 20 miles but increased to 40 miles by early afternoon.  Skies remained mostly cloudy all day with altostratus and cirrostratus and were overcast at the 1:00PM ob. Rising temperatures helped to clear the morning fog and reached a max. of 40F by 1:00PM.  The overnight low of 33F is 7F above the normal low; however, temperatures are expected to drop even further with the arrival of a cold front later this evening.  Winds remained light and out of the WSW-SW during each observation. 7 A.M. Weather: Scattered altostratus, broken cirrostratus, inversion present with an estimated top of 400 ft., radiation fog below inversion Temperature: 35F; Dew Point: 32F; Wind: WSW at 5 kts, Wind Speed: Light Sea-level pressure: 29.93 ins. Hg, rising then falling Visibility: 20 miles, distant fog in all directions 6-hr Max temp: 35F 6-hr Min temp: 33F 24-hr precip: 0.01 in. BHO SA 1155 120 SCT E200 BKN 20 136/35/32/2405/993/ DSNT FG ALQDS WND LGT INVSN PRSNT ESTMD TOP 4 HND GF BLO INVSN/ 8/018 58004 MANUAL 70001 ASOS 70002 10035 20033 10 A.M. Weather: Scattered altostratus, broken cirrostratus Temperature: 38F; Dew Point: 34F; Wind: SW at 6 kts, Wind Speed: Light Sea-level pressure: 29.91 ins. Hg, falling, then more quickly Visibility: 20 miles BHO SA 1455 120 SCT E200 BKN 20 129/38/34/2306/991/ DSNT FG ALQDS WND LGT/ 8/018 58007 1 P.M. Weather: Broken altostratus, overcast cirrostratus Temperature: 40F; Dew Point: 30F; Wind: WSW at 6 kts, Wind Speed: Light Sea-level pressure: 29.80 ins. Hg, falling, then more quickly Visibility: 40 miles 6-hr Max temp: 40F 6-hr Min temp: 34F BHO SA 1755 E89 BKN 200 OVC 40 091/40/30/2406/980/ WND LGT/ 8/018 56038 10040 20034 SUMMARY FOR WEDNESDAY, DECEMBER 7, 2016   TEMPERATURE (DEGREES F) MAX.....39   NORMAL.....42 MIN.....34   NORMAL.....27 MEAN....37   NORMAL.....34 DEPARTURE FROM 30-YEAR NORMAL........................+3 TOTAL DEPARTURE FOR THE MONTH.......................+16 [+2.1 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............28   DEPARTURE..........-3 TOTAL HEATING UNITS FOR THE MONTH.............191   DEPARTURE.........-16 TOTAL HEATING UNITS FOR THE SEASON...........1121   DEPARTURE........-248 TOTAL HEATING UNITS LAST SEASON TO DATE......1157   DIFFERENCE........+64 PEAK GUST AND AVERAGE WIND SPEED (MPH)  PEAK WIND GUST FOR YESTERDAY...................21 E   AT 2:22 A.M.                    ASOS........................21 E   AT 2:22 A.M.                    DAVIS.......................19 E   AT 2:22 A.M. RMY N/A FASTEST MILE FOR YESTERDAY.....................14 E   AT 2:22 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE..................15 E   AT 2:23 A.M.  MAXIMUM 2-MINUTE DAVIS AVERAGE.................14 ENE AT 3:31 A.M. AVERAGE WIND SPEED AND DIRECTION..............6.6 SW                    ASOS.......................6.8                    DAVIS......................6.0 W [260 Deg.] *last of multiple occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.01  DEPARTURE......-0.16                          ASOS..............0.02 TOTAL PRECIPITATION FOR THE MONTH..........0.43  DEPARTURE......-0.72                          ASOS..............0.49 TOTAL PRECIPITATION FOR THE YEAR..........37.40  DEPARTURE.....-12.28                          ASOS.............37.92 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE.......-0.3 TOTAL SNOWFALL FOR THE MONTH................0.4  DEPARTURE.......-1.3 TOTAL SNOWFALL FOR THE SEASON...............0.4  DEPARTURE.......-3.9 PRELIMINARY CLIMATE SUMMARY FOR DECEMBER CALENDAR DAY DATA DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST AERO: Aerovane wind recording system gust RMY:  R.M. Young wind gust recording system TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized M:    Missing data 12/1  55/39/47/+10/0.20/0.0/385/69          36 W   AERO 37 W   RMY 36 12/2  48/34/41/+5/0.00/0.0/535/96           32 W   AERO 32 W   RMY N/A 13/3  44/31/38/+2/0.00/0.0/.../..           37 WNW AERO 39 WNW RMY 40 12/4  39/27/33/-2/0.00/0.0/.../..           25 NW  AERO 25 NW  RMY N/A 12/5  36/27/32/-3/0.13/0.4/.../..           26 W   AERO 25 W   RMY 29 12/6  42/30/36/+1/0.00/0.0/.../..           22 W   AERO 21 W   RMY N/A 12/7  39/34/37/+3/0.10/0.0/.../..           21 E   AERO 21 E   RMY N/A 12/8  Low temp since midnight is 33F; normal low is now 26F DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR DECEMBER 8 HIGH 62 IN 1966 LOW -4 IN 1906 PRECIP 1.54 INS. IN 1969 SNOWFALL 2.5 INS. IN 2001 PEAK GUST 78e W IN 1979 RECORDS FOR DECEMBER 9 HIGH 68 IN 1966 LOW -14 IN 1902 PRECIP 3.23 INS. IN 2014 SNOWFALL 10.8 INS. IN 2005 PEAK GUST 66 SE IN 1973   TODAY'S REPORT PREPARED BY: Cecilia Borries-Strigle