BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA

FRIDAY, DECEMBER 25, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

SIGNIFICANT WIND AND RAIN FOR CHRISTMAS,
IT MUST BE 2020....

Today we observed a limited visibility of 
1 mile at most due to fog. Rain began a little 
before 6 A.M., leaving 0.58 inches in the gauge
by the 7 A.M. observation. A heavy band of rain
came through, giving us another 0.77 inches
before 10 A.M. Wind is very strong today, as we
are seeing frequent gusts of 40 mph. The average
wind speed is almost 30 mph, with the highest
gust of the day being 69 mph. The current wind
record for the calendar date is 84 mph, set in
1957. The rainfall record for today is 1.37 
inches in 2002, making this day almost a record
setter. With the rain continuing past the 
morning observations, Great Blue Hill should 
have no problem breaking this record. 

Today is much, much warmer than usual given the 
time of year. The high so far today is 59F, 23 degrees 
above the daily normal maximum of 36F. The low since 
midnight is 53F, 32 degrees above the normal minimum 
of 21F.

Merry Christmas, and let's hope for a happy new year! 


Today's Observations:

7 A.M.
Weather: Overcast stratus, heavy rain becoming lighter
around 6:35 A.M.  
Temperature: 58F; Dew Point: 58F; Relative Humidity: 100%
Wind: SE @ 29G41 kts, peak 53 SSE at 6:53 A.M.  
Sea-level pressure: 29.64 in Hg; falling steadily
Visibility: 1 mile, fog
6-hr Max temp: 58F
6-hr Min temp: 54F
24-hr Precip: 0.58 ins.
24-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1155 20 OVC 1R-F 037/58/58/1529G41/964/ R+ BCMG 
R-35 R-CTD PK WND 1646/53/ 8/6// 70058 56028 10058 20054

10 A.M.
Weather: Overcast stratus, heavy rain becoming lighter
at 9:25 A.M. 
Temperature: 58F; Dew Point: 58F; Relative Humidity: 100%
Wind: S @ 24G34 kts, peak of 69 SSE at 8:44 A.M. 
Sea-level pressure: 29.61 in Hg; falling steadily
Visibility: 1 mile, fog
3-hr Precip: 0.77 ins.
3-hr Snow: 0.0 ins.
BHO SA 1455 20 OVC 1RF 032/58/58/1724G34/961/ R+ BCMG 
R25 RCTD PK WND 1660/1344/ 8/6// 6077/ 55009


SUMMARY FOR THURSDAY, DECEMBER 24, 2020 

TEMPERATURE (DEGREES F)
MAX.......53   NORMAL.....37 
MIN.......30   NORMAL.....21
MEAN......42   NORMAL.....29

DEPARTURE FROM 30-YEAR NORMAL.....................+13
TOTAL DEPARTURE FOR THE MONTH.....................+34 [+1.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............23  DEPARTURE......-13
TOTAL HEATING UNITS FOR THE MONTH..............745  DEPARTURE......-37
TOTAL HEATING UNITS FOR THE SEASON............1718  DEPARTURE.....-325
TOTAL HEATING UNITS LAST SEASON TO DATE.......2047  DEPARTURE.....-329

PEAK WIND GUST FOR YESTERDAY (MPH):
                     420C/Official..............46 SSE @  9:51 P.M.
                     AEROVANE (south tower).....50 SSE @ 10:02 P.M.
                     ASOS.......................47 SSE @ 10:26 P.M.
                     DAVIS #1...................51 SSE @ 10:02 P.M.
                     DAVIS #2 (south tower).....49 SSE @  9:04 P.M.
                     RMY........................55      
                     VECTOR.....................56     
                     MERLIN.....................N/A

FASTEST MILE FOR YESTERDAY:
CONTACTING/OFFICIAL.............................34 SSE @ 10:22 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE...................31 SSE @  9:52 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE...............35 SSE @  9:52 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE...............34 SE  @  9:52 P.M.

AVERAGE WIND SPEED AND DIRECTION:
                     CONTACTING/OFFICIAL...21.6 SSE [519 total miles]
                     ASOS..................19.8     [475 total miles]
                     DAVIS #1..............21.6 W   [518 total miles]
                     DAVIS #2..............22.6 W   [542 total miles]
                     RMY...................20.9 W   [502 total miles]
                     VECTOR................21.4     [506 total miles]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.......0.58  DEPARTURE....+0.43
                             ASOS.............0.58
TOTAL PRECIPITATION FOR THE MONTH.............5.61  DEPARTURE....+1.75
                             ASOS.............6.11
TOTAL PRECIPITATION FOR THE YEAR.............52.01  DEPARTURE....-0.38
                              ASOS...........53.44

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HOURS ENDING 7 A.M...........0.0  DEPARTURE.....-0.5
TOTAL SNOWFALL FOR THE MONTH..................19.7  DEPARTURE....+10.0
TOTAL SNOWFALL FOR THE SEASON.................26.2  DEPARTURE....+13.9


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

12/01   62/40/51/+14/0.61/0.0/.../..      60 S    AERO 67 W    RMY 64
12/02   42/32/37/+1/0.00/0.0/.../..       32 SW   AERO 32 SW   RMY 35
12/03   49/30/40/+4/0.00/0.0/.../..       25 SSW  AERO 25 SSW  RMY 28
12/04   58/40/49/+14/0.06/0.0/.../..      35 SSW  AERO 35 SSW  RMY 37
12/05   42/32/37/+2/2.13/2.8/.../..       58 NNW  AERO 58 NNW  RMY 67
12/06   34/26/30/-5/0.01/T/.../..        E44 WNW  AERO 44 WNW  RMY 49
12/07   33/22/28/-6/T/T/.../..            24 NW   AERO 26 NW   RMY 26
12/08   29/22/26/-8/T/T/.../..            24 NW   AERO 25 NW   RMY 28
12/09   34/19/27/-7/T/T/.../..            16 W    AERO 17 W    RMY 19
12/10   42/30/36/+3/0.00/0.0/.../..       30 WNW  AERO 31 WNW  RMY 29
12/11   50/31/41/+8/0.00/0.0/.../..       32 SW   AERO 35 SW   RMY 34
12/12   48/40/44/+11/0.38/0.0/.../..      25 E    AERO 21 E    RMY 25
12/13   58/35/47/+15/0.00/0.0.../..       28 W    AERO 31 WSW  RMY 31
12/14   35/30/33/+1/0.10/0.4/.../..       25 N    AERO 25 N    RMY 29
12/15   34/21/28/-4/0.00/0.0/.../..       32 WNW  AERO 33 WNW  RMY 38
12/16   27/13/20/-11/..../1.4/.../..      38 E    AERO 37 E    RMY 39
12/17   31/19/25/-6/..../15.1/.../..      55 ENE  AERO 56 ENE  RMY 59
12/18   27/18/23/-8/0.00/0.0/.../..       28 N    AERO 26 N    RMY 27
12/19   29/13/21/-9/0.00/0.0/.../..       16 SW   AERO 16 S    RMY 16
12/20   36/24/30/0/0.02/T/.../..          14 S    AERO 16 SW   RMY 14
12/21   34/29/32/+2/0.00/0.0/.../..       22 WNW  AERO 24 WNW  RMY 23
12/22   42/30/36/+7/0.00/0.0/.../...      34 WNW  AERO 35 WNW  RMY 38
12/23   37/26/32/+3/0.00/0.0/.../..       30 WNW  AERO 28 WNW  RMY 31
12/24   53/30/42/+13/..../.../.../..      46 SSE  AERO 50 SSE  RMY 55

12/25   The low since midnight is 53F, the daily normal low is 21F


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

DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):

RECORDS FOR DECEMBER 25
HIGH 64 IN 2015
LOW -11 IN 1980
PRECIP 1.37 INS. IN 2002
SNOWFALL 8.5 INS. IN 2002
PEAK GUST 80 MPH NW IN 1971

RECORDS FOR DECEMBER 26
HIGH 58 IN 1973,1982
LOW -12 IN 1980
PRECIP 3.64 INS. IN 1969
SNOWFALL 17.5 INS. IN 1909
PEAK GUST 84 MPH SSE IN 1957

TODAY'S REPORT PREPARED BY: Benjamin Turner