BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA SATURDAY, JANUARY 9, 2021 ALL TIMES ARE IN EASTERN STANDARD TIME PARTLY CLOUDY WITH A NORTHERLY BREEZE AND GOOD VISIBILITY.... Today we observed partly cloudy skies and a visibility of 75 miles. Wind was northerly at an average around 10 mph and a peak gust of 24 mph since 7 A.M. The ponds are mostly frozen over, and despite abundant sunshine they have stayed 7/10ths frozen. This is due to the seasonable overnight lows being in the upper teens and lower 20's. Conditions are dry, with a current temp of 33F and a dew point of 16F. That leaves us with a relative humidity of 49%.   The high so far today is 34F, the same as the daily normal maximum. The low since midnight is 20F, 3 degrees above the normal minimum of 17F. PRELIMINARY STATS FOR DECEMBER 2020 TEMPERATURE, Deg. F Avg. Max. 41.1 [+2.0] Avg. Min. 27.2 [+3.6] Mean      34.2 [+2.9] 24-hour corrected mean: 34.0 Max. for month: 62F on the 1st Min. for month: 13F on the 16th and 19th HEATING DEGREE DAYS Total heating units:   957 [-86] Total for the season:  1930 [-375] Total for last season: 2251 PRECIPITATION, Inches Total: 7.32 [+2.43] Greatest in 24 hrs: 2.15 ins. on the 25th SNOWFALL, Inches Total: 19.7 [+6.3] Greatest in 24 hrs: 16.5 ins. on the 16th-17th WIND, mph Avg. uncorrected wind speed: 13.0 mph Avg. corrected wind speed:   13.3 mph Prevailing wind direction:   WNW [17%] Peak gust and direction:     68 SSE on the 25th SUNSHINE: Campbell-Stokes card minutes: 6756 minutes of a possible 16470 or 41% Astronomical total minutes: 6961 minutes of a possible 16991 or 41% Today's Observations: 7 A.M. Weather: Scattered altocumulus Temperature: 20F; Dew Point: 11F; Relative Humidity: 67% Wind: NNW at 10 kts Sea-level pressure: 29.83 in Hg; steady, then rising Visibility: 60 miles 6-hr Max temp: 24F 6-hr Min temp: 20F 24-hr Precip: 0.00 ins. 24-hr Snow: 0.0 ins. Snow Depth: 0 ins. BHO SA 1155 70 SCT 60 100/20/11/3410/983/ 8/080 53002 10024 20020 10 A.M. Weather: Scattered cirrocumulus Temperature: 27F; Dew Point: 13F; Relative Humidity: 55% Wind: N at 9G18 kts Sea-level pressure: 29.85 in Hg; steady, then rising Visibility: 75 miles 3-hr Precip: 0.00 ins. 3-hr Snow: 0.0 ins. BHO SA 1455 250 SCT 75 108/27/13/3609G18/985/ 8/006 50008 1 P.M. Weather: Scattered stratocumulus, broken altocumulus and cirrocumulus Temperature: 34F, Dew point: 14F; Relative Humidity: 44% Wind: NNE at 4 kts (wind light and variable) Sea-level pressure: 29.79 inches Hg, falling, then falling more slowly Visibility: 75 miles 6-hr Max temp: 34F 6-hr Min temp: 20F 6-hr Precip: 0.00 ins. 6-hr Snow: 0.0 ins. Snow Depth: 0 ins. BHO SA 1755 30 SCT 100 BKN 250 BKN 75 090/34/14/0204/979/ WND L/V/ 8/559 56018 10034 20020 SUMMARY FOR FRIDAY, JANUARY 8, 2021 TEMPERATURE (DEGREES F) MAX.......40   NORMAL.....34 MIN.......21   NORMAL.....18 MEAN......31   NORMAL.....26 DEPARTURE FROM 30-YEAR (1981-2010) NORMAL........+5 TOTAL DEPARTURE FOR THE MONTH...................+49 [+5.9 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY...............34  DEPARTURE.......-5 TOTAL HEATING UNITS FOR THE MONTH..............261  DEPARTURE......-49 TOTAL HEATING UNITS FOR THE SEASON............2191  DEPARTURE.....-424 TOTAL HEATING UNITS LAST SEASON TO DATE.......2492  DEPARTURE.....-301 PEAK WIND GUST (MPH):                      420C/Official..............25 NNW  @  9:32 P.M.                      AEROVANE (south tower).....22 NNW  @  9:38 P.M.                      ASOS.......................23 NW   @ 12:13 A.M.                      DAVIS #1...................24 NNW  @ 12:12 A.M.                      DAVIS #2 (south tower).....22 NNW  @ 12:12 A.M.                      RMY........................25      @ 12:12 A.M.                      VECTOR.....................27      @ 12:39 A.M.                      MERLIN.....................N/A FASTEST MILE: CONTACTING ANEMOMETER/OFFICIAL..................19 NNW @ 12:16 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...................18 NW  @ 12:13 A.M. MAXIMUM 2-MINUTE DAVIS #1 AVERAGE...............19 NNW @ 12:14 A.M. MAXIMUM 2-MINUTE DAVIS #2 AVERAGE...............18 NNW @ 12:13 A.M. MAXIMUM 2-MINUTE RMY AVERAGE....................18 NNW @ 12:10 A.M. MAXIMUM 2-MINUTE VECTOR AVERAGE.................18     @ 12:11 A.M. AVERAGE WIND SPEED AND DIRECTION:                      CONTACTING/OFFICIAL...9.4  NW  [226 total miles]                      ASOS..................9.5      [230 total miles]                      DAVIS #1..............9.5  NNW [230 total miles]                      DAVIS #2..............10.0 NNW [235 total miles]                      RMY...................9.4  NNW [226 total miles]                      VECTOR................9.5      [230 total miles] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST): TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.......0.00  DEPARTURE....-0.14                              ASOS.............0.00 TOTAL PRECIPITATION FOR THE MONTH.............0.49  DEPARTURE....-0.65                              ASOS.............0.48 TOTAL PRECIPITATION FOR THE YEAR..............0.49  DEPARTURE....-0.65                               ASOS............0.48 SNOWFALL (INCHES) THROUGH THIS MORNING (EST): TOTAL SNOWFALL 24 HOURS ENDING 7 A.M...........0.0  DEPARTURE.....-0.6 TOTAL SNOWFALL FOR THE MONTH.................. 1.9  DEPARTURE.....-2.6 TOTAL SNOWFALL FOR THE SEASON.................28.1  DEPARTURE.....+7.6 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 12/01   62/40/51/+14/0.61/0.0/112/20      60 S    AERO 67 W    RMY 64 12/02   42/32/37/+1/0.00/0.0/301/54       32 SW   AERO 32 SW   RMY 35 12/03   49/30/40/+4/0.00/0.0/512/92       25 SSW  AERO 25 SSW  RMY 28 12/04   58/40/49/+14/0.06/0.0/332/60      35 SSW  AERO 35 SSW  RMY 37 12/05   42/32/37/+2/2.13/2.8/000/00       58 NNW  AERO 58 NNW  RMY 67 12/06   34/26/30/-5/0.01/T/403/73        E44 WNW  AERO 44 WNW  RMY 49 12/07   33/22/28/-6/T/T/457/83            24 NW   AERO 26 NW   RMY 26 12/08   29/22/26/-8/T/T/006/01            24 NW   AERO 25 NW   RMY 28 12/09   34/19/27/-7/T/T/000/00            16 W    AERO 17 W    RMY 19 12/10   42/30/36/+3/0.00/0.0/351/64       30 WNW  AERO 31 WNW  RMY 29 12/11   50/31/41/+8/0.00/0.0/384/70       32 SW   AERO 35 SW   RMY 34 12/12   48/40/44/+11/0.38/0.0/000/00      25 E    AERO 21 E    RMY 25 12/13   58/35/47/+15/0.00/0.0/109/20      28 W    AERO 31 WSW  RMY 31 12/14   35/30/33/+1/0.10/0.4/000/00       25 N    AERO 25 N    RMY 29 12/15   34/21/28/-4/0.00/0.0/541/99       32 WNW  AERO 33 WNW  RMY 38 12/16   27/13/20/-11/0.14/1.4/180/33      38 E    AERO 37 E    RMY 39 12/17   31/19/25/-6/1.58/15.1/000/00      55 ENE  AERO 56 ENE  RMY 59 12/18   27/18/23/-8/0.00/0.0/120/22       28 N    AERO 26 N    RMY 27 12/19   29/13/21/-9/0.00/0.0/436/80       16 SW   AERO 16 S    RMY 16 12/20   36/24/30/0/0.02/T/000/00          14 S    AERO 16 SW   RMY 14 12/21   34/29/32/+2/0.00/0.0/000/00       22 WNW  AERO 24 WNW  RMY 23 12/22   42/30/36/+7/0.00/0.0/447/82       34 WNW  AERO 35 WNW  RMY 38 12/23   37/26/32/+3/0.00/0.0/480/88       30 WNW  AERO 28 WNW  RMY 31 12/24   53/30/42/+13/T/0.0/153/28         46 SSE  AERO 50 SSE  RMY 55 12/25   61/37/49/+21/2.15/0.0/000/00      68 SSE  AERO 77 SSE  RMY 84 12/26   37/25/31/+3/0.00/0.0/485/89       38 SW   AERO 44 SW   RMY 43 12/27   38/22/30/+2/0.00/0.0/513/94       18 W    AERO 18 W    RMY 20 12/28   49/27/38/+10/T/0.0/109/20         35 SSW  AERO 36 -    RMY 37 12/29   38/20/29/+2/0.00/0.0/470/86       48 WNW  AERO 50 WNW  RMY 56 12/30   40/19/30/+3/0.00/0.0/060/11       39 SW   AERO 41 SW   RMY 45 12/31   44/28/36/+9/0.14/0.0/000/00       38 SW   AERO 43 SW   RMY 43 DAILY RECORDS FOR DECEMBER 2020 12/17/20: DAILY RECORD SNOWFALL OF 15.1 INCHES,           BREAKS PREVIOUS RECORD OF 7.5 INCHES SET IN 1988 12/25/20: DAILY RECORD PRECIPITATION OF 2.15 INCHES,           BREAKS PREVIOUS RECORD OF 1.37 INCHES SET IN 2002 PRELIMINARY CLIMATE SUMMARY FOR JANUARY 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 01/01   36/25/31/+4/0.06/0.3/.../..       23 E    AERO 23 NNW  RMY 23 01/02   43/30/37/+10/0.30/T/.../..        37 WNW  AERO 39 WNW  RMY 44 01/03   33/27/30/+4/0.07/0.8/.../..       23 NNE  AERO 22 NNE  RMY 25 01/04   37/28/33/+7/0.01/0.1/.../..       25 NNE  AERO 23 NNE  RMY 27 01/05   31/28/30/+4/0.05/0.7/.../..       21 NNW  AERO 21 NNW  RMY 22 01/06   38/28/33/+7/T/T/.../..            30 NW   AERO 29 NW   RMY 32 01/07   42/26/34/+8/0.00/0.0/.../..       28 NNW  AERO 26 NNW  RMY 31 01/08   40/21/31/+5/0.00/0.0/.../...      25 NNW  AERO 22 NNW  RMY 25 01/09 The low since midnight is 20F, the daily normal low is 17F DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JANUARY 9 HIGH 62F IN 1937 LOW -9F IN 1968 PRECIP 3.00 INS. IN 1956 SNOWFALL 10.0 INS. IN 1904 PEAK GUST 101e MPH SE IN 1978 [RECORD FOR MONTH] RECORDS FOR JANUARY 10 HIGH 58F IN 2016 LOW -7F IN 2004 PRECIP 2.16 INS. IN 1935 SNOWFALL 6.3 INS. IN 1977 PEAK GUST 73e SE IN 1977 TODAY'S REPORT PREPARED BY: Benjamin Turner