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

SATURDAY, DECEMBER 26, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

CHILLY DAY WITH CLEARING SKIES ON TOP 
OF THE GREAT BLUE HILL….

Temperatures begin decreasing from 
yesterday’s above average highs. 
Overnight temperatures lowering to 
the upper 20s around the 7 A.M 
observation. Precipitation record 
for yesterday was broken with a 
storm total of 2.15 inches of rain. 
Winds were very strong during 
yesterday's storm however no record 
was broken. Winds stayed relativity 
gusty during the afternoon today with 
our peak gust so far reaching 29 miles 
per hour. The high so far today is 27F, 
9 degrees below the daily normal maximum 
of 36F. The low since midnight is 27F, 6 
degrees above the normal minimum of 21F.


Today's Observations:

7 A.M.
Weather: Broken stratus  
Temperature: 27F; Dew Point: 21F; Relative Humidity: 100%
Wind: SSW @ 12G20 kts  
Sea-level pressure: 29.72 in Hg; steadily then rising
Visibility: 35 mile
6-hr Max temp: 34F
6-hr Min temp: 27F
24-hr Precip: 1.57 ins.
24-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1155 35 BKN 35 067/27/21/2112G20/972/ 8/600 70157 
53018 10034 20027

10 A.M.
Weather: Scattered cumulus, Scattered stratus
Temperature: 29F; Dew Point: 20F; Relative Humidity: 70%
Wind: SW @ 14G23 kts 
Sea-level pressure: 29.76 in Hg; steadily then rising
Visibility: 40 mile
3-hr Precip: 0.00 ins.
3-hr Snow: 0.0 ins.
BHO SA 1455 40 SCT 25 SCT 250 078/29/20/2214G23/976/ 8/208 53014

1 P.M.
Weather: Few cumulus
Temperature: 30F, Dew point: 20F; Wind: W at 28G25 kts,
Sea-level pressure: 29.72 inches Hg, rising then falling 
Visibility: 70 miles   
6-hour max. temp: 30F   
BHO SA 1755 70 CLR 066/30/20/2718G25/972/ FEW CU ALQDS 8/100 
58012 10030 20027


SUMMARY FOR FRIDAY, DECEMBER 25, 2020 

TEMPERATURE (DEGREES F)
MAX.......61   NORMAL.....37 
MIN.......37   NORMAL.....21
MEAN......49   NORMAL.....29

DEPARTURE FROM 30-YEAR NORMAL.....................+21
TOTAL DEPARTURE FOR THE MONTH.....................+55 [+2.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............16  DEPARTURE......-7
TOTAL HEATING UNITS FOR THE MONTH..............761  DEPARTURE......-57
TOTAL HEATING UNITS FOR THE SEASON............1734  DEPARTURE.....-346
TOTAL HEATING UNITS LAST SEASON TO DATE.......2080  DEPARTURE.....-344

PEAK WIND GUST FOR YESTERDAY (MPH):
                     420C/Official..............68 SSE @ 8:44 A.M.
                     AEROVANE (south tower).....77 SSE @ 8:42 A.M.
                     ASOS.......................67 SSW @ 8:59 A.M.
                     DAVIS #1...................73 S   @ 8:36 A.M.
                     DAVIS #2 (south tower).....78 SSE @ 8:13 A.M.
                     RMY........................83.8      
                     VECTOR.....................83.4     
                     MERLIN.....................N/A

FASTEST MILE FOR YESTERDAY:
CONTACTING/OFFICIAL.............................52 SSE @ 8:18 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE...................46 S   @  9:00 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE...............47 S   @  7:41 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE...............53 SSE @ 8:32 A.M.

AVERAGE WIND SPEED AND DIRECTION:
                     CONTACTING/OFFICIAL...25.4 SSE [609 total miles]
                     ASOS..................23.2     [557 total miles]
                     DAVIS #1..............24.2 S   [581 total miles]
                     DAVIS #2..............26.0 S   [624 total miles]
                     RMY...................24.1 S   [578 total miles]
                     VECTOR................24.6     [590 total miles]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.......1.57  DEPARTURE....+1.41
                             ASOS.............1.66
TOTAL PRECIPITATION FOR THE MONTH.............5.61  DEPARTURE....+1.59
                             ASOS.............7.77
TOTAL PRECIPITATION FOR THE YEAR.............53.58  DEPARTURE....1.03
                              ASOS...........55.10

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....+9.5
TOTAL SNOWFALL FOR THE SEASON.................26.2  DEPARTURE....+13.4


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   61/37/49/+21/..../.../.../..      68 SSE  AERO 77 SSE  RMY 84

12/26 The low since midnight is 27F, 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 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

RECORDS FOR DECEMBER 27
HIGH 57 IN 1895,1949
LOW -4 IN 1903
PRECIP 2.43 INS. IN 1969
SNOWFALL 11.2 INS. IN 1947
PEAK GUST 73 S IN 2011

TODAY'S REPORT PREPARED BY: Nicholas Rousseau