Friday, January 8, 2021

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

FRIDAY, JANUARY 8, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)

CLEAR SKIES, PLENTIFUL SUNSHINE & SEASONABLE TEMPS
TO BEGIN THE WEEKEND…

Skies were mostly clear today allowing for abundant
sunshine. A few cumulus have been spotted well offshore
along with some high-level cirrus to our distant south.
Winds have eased from yesterday- averaging about 7 MPH
so far today. Visibility began at 50 miles increasing
to near perfect at 85 miles by early afternoon! A very
tranquil day!

As we looked beyond the observatory, both Houghton’s Pond
and Ponkapoag Pond gained some ice coverage overnight with
lows dipping into the low-20s. The coverage has retreated
throughout the day, however, with highs nudging into the
upper 30s. It still remains insufficient for any winter
activities. Last year featured no opportunities to do so
given the very mild season. We’ll see how the rest of
the winter unfolds!

The high so far today is 38F, 4 degrees above the daily
normal maximum of 34F. The low since midnight is 21F,
3 degrees above the normal minimum of 18F.

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: Clear (few cumulus offshore ESE, Few cirrus southeast to south)
Temperature: 21F; Dew Point: 17F; Relative Humidity: 83%
Wind: NW at 8 kts
Sea-level pressure: 29.96 in Hg; falling, then rising
Visibility: 50 miles
6-hr Max temp: 26F
6-hr Min temp: 21F
24-hr Precip: 0.00 ins.
24-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1155 CLR 50 146/21/17/3208/996/ FEW CU OFFSHR DSNT ESE FEW CI DSNT SE-S/ 8/102 55002 10026 20021

10 A.M.
Weather: Scattered Cirrus (thin smoke layer along horizon west-southwest
to northeast)
Temperature: 28F; Dew Point: 18F; Relative Humidity: 66%
Wind: NW at 10 kts
Sea-level pressure: 29.95 in Hg; steady, then falling
Visibility: 80 miles
3-hr Precip: 0.00 ins.
3-hr Snow: 0.0 ins.
BHO SA 1455 250 SCT 80 141/28/18/3210/995/ THN K LYR ALG HRZN WSW-NE/ 8/002 58005

1 P.M.
Weather: Scattered Cirrus
Temperature: 37F, Dew point: 16F; Relative Humidity: 42%
Wind: WNW at 6 kts (wind light)
Sea-level pressure: 29.88 inches Hg, falling, then falling more slowly
Visibility: 85 miles
6-hr Max temp: 38F
6-hr Min temp: 21F
6-hr Precip: 0.00 ins.
6-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1755 250 SCT 85 118/37/16/2906/988/ WND LGT/ 8/002 56023 10038 20021

SUMMARY FOR THURSDAY, JANUARY 7, 2021

TEMPERATURE (DEGREES F)
MAX…….42   NORMAL…..34
MIN…….26   NORMAL…..18
MEAN……34   NORMAL…..26

DEPARTURE FROM 30-YEAR (1981-2010) NORMAL……..+8
TOTAL DEPARTURE FOR THE MONTH……………….+44 [+6.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………31  DEPARTURE…….-8
TOTAL HEATING UNITS FOR THE MONTH…………..227  DEPARTURE……-44
TOTAL HEATING UNITS FOR THE SEASON…………2157  DEPARTURE…..-418
TOTAL HEATING UNITS LAST SEASON TO DATE…….2458  DEPARTURE…..-301

PEAK WIND GUST (MPH):
420C/Official…………..28 NNW  @ 7:54 P.M.
AEROVANE (south tower)…..26 NNW  @ 8:57 P.M.
ASOS…………………..29 NNW  @ 7:54 P.M.
DAVIS #1……………….28 NNW  @ 8:01 P.M.
DAVIS #2 (south tower)…..27 NW   @ 7:58 P.M.
RMY……………………31      @ 8:00 P.M.
VECTOR…………………31      @ 8:03 P.M.
MERLIN…………………27

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………19 NNW @  7:57 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….18 NNW @ 10:11 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………20 NW  @  5:36 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………20 NNW @  8:40 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..19 NNW @  8:39 A.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE……………..19     @ 10:08 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…13.2 NW  [316 total miles] ASOS………………13.3     [319 total miles] DAVIS #1…………..13.7 NW  [329 total miles] DAVIS #2…………..13.4 NNW [322 total miles] RMY……………….12.9 NNW [310 total miles] VECTOR…………….13.4     [322 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….-0.51
ASOS………….0.48
TOTAL PRECIPITATION FOR THE YEAR…………..0.49  DEPARTURE….-0.51
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…..-2.0
TOTAL SNOWFALL FOR THE SEASON……………..28.1  DEPARTURE…..+8.2

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/+4/0.03/0.3/…/..      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 The low since midnight is 21F, the daily normal low is 18F

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

RECORDS FOR JANUARY 8
HIGH 65F IN 2008
LOW -8F IN 1968
PRECIP 1.70 INS. IN 1958,1979
SNOWFALL 12.5 INS. IN 1996
PEAK GUST 77 MPH NNW IN 1958

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]

TODAY’S REPORT PREPARED BY: Andrew Swanson