Wednesday, January 6, 2021

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

WEDNESDAY, JANUARY 6, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME

PARTLY CLOUDY WITH AN INCREASING NORTHWESTERLY
WIND ATOP GREAT BLUE HILL….

Today we measured 0.3 inches of snow that fell
overnight, amounting to 0.03 inches of liquid.
Wind was northwesterly for most of the day,
with a max gust of 29 mph in the evening hours.
Visibility was limited to 30 miles this morning
due to a thin layer of fog, but increased to
over 80 miles by the end of the day.

The high so far today is 38F, 4 degrees above
the daily normal maximum of 34F. The low since
midnight is 28F, 10 degrees above the normal
minimum of 18F. Overnight lows have stayed
higher than normal, and it shows on both
Houghton’s Pond and Ponkapoag Pond. There is
barely any ice on them!

BHO Warmest Annual 24-Hour Adjusted Mean Temperature,
deg F (1885-2020):

1) 51.7 in 2012
2) 51.3 in 2020
3) 51.2 in 2016
4) 51.0 in 2010
5) 50.9 in 1999
6) 50.8 in 1998
7) 50.6 in 2006
8) 50.5 in 1953

Today’s Observations:

7 A.M.
Weather: Scattered altocumulus, broken cirrostratus,
few cumulus
Temperature: 28F; Dew Point: 26F; Relative Humidity: 93%
Wind: NNW at 10 kts
Sea-level pressure: 29.86 in Hg; rising steadily
Visibility: 30 miles, thin fog
6-hr Max temp: 29F
6-hr Min temp: 28F
24-hr Precip: 0.03 ins.
24-hr Snow: 0.3 ins.
Snow Depth: Trace
BHO SA 1155 90 SCT 250 BKN 30 111/28/26/3310/986/ FEW CU OFFSHR
THN F ALQDS NEW SNW PST 24 HRS 0.3 INS/ 8/176 70003 53002 10029
20028

10 A.M.
Weather: Broken altocumulus
Temperature: 33F; Dew Point: 27F; Relative Humidity: 78%
Wind: NW at 12G19 kts
Sea-level pressure: 29.87 in Hg; falling, then rising
Visibility: 70 miles
3-hr Precip: 0.00 ins.
3-hr Snow: 0.0 ins.
BHO SA 1455 100 BKN 70 116/33/27/3112G19/987/ 8/070 51005

1 P.M.
Weather: Broken altocumulus
Temperature: 36F, Dew point: 25F; Relative Humidity: 63%
Wind: NW at 11G19 kts
Sea-level pressure: 29.83 inches Hg, falling, then more slowly
Visibility: 80 miles
6-hr Max temp: 38F
6-hr Min temp: 28F
6-hr Precip: 0.00 ins.
6-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1755 100 BKN 80 102/36/25/3111G19/983/ 8/070 56014 10038
20028

SUMMARY FOR TUESDAY, JANUARY 5, 2021

TEMPERATURE (DEGREES F)
MAX…….31   NORMAL…..34
MIN…….28   NORMAL…..18
MEAN……30   NORMAL…..26

DEPARTURE FROM 30-YEAR NORMAL………………….+4
TOTAL DEPARTURE FOR THE MONTH…………………+29 [+5.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………35  DEPARTURE…… -4
TOTAL HEATING UNITS FOR THE MONTH…………..164  DEPARTURE……-29
TOTAL HEATING UNITS FOR THE SEASON…………2094  DEPARTURE…..-403
TOTAL HEATING UNITS LAST SEASON TO DATE…….2390  DEPARTURE…..-296

PEAK WIND GUST FOR YESTERDAY (MPH):
420C/Official…………..21 NNW @ 11:54 P.M.
AEROVANE (south tower)…..21 NNW @ 11:43 P.M.
ASOS…………………..21 N   @ 11:32 P.M.
DAVIS #1……………….20 N   @ 11:31 P.M.
DAVIS #2 (south tower)…..21 NNW @ 11:56 P.M.
RMY……………………22
VECTOR…………………22
MERLIN…………………N/A

FASTEST MILE FOR YESTERDAY:
CONTACTING/OFFICIAL………………………..15 NNW @ 11:46 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….15 N   @ 11:32 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………14 N   @ 11:46 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………15 NNW @ 12:50 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..14 NNE @ 11:42 P.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE……………..14     @ 11:43 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL… 9.4 NNW [226 total miles] ASOS………………10.0     [240 total miles] DAVIS #1………….. 9.7 N   [228 total miles] DAVIS #2………….. 9.8 N   [228 total miles] RMY………………. 9.4 N   [226 total miles] VECTOR……………. 9.9     [229 total miles]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.03  DEPARTURE….-0.11
ASOS………….0.03
TOTAL PRECIPITATION FOR THE MONTH………….0.49  DEPARTURE….-0.23
ASOS………….0.48
TOTAL PRECIPITATION FOR THE YEAR…………..0.49  DEPARTURE….-0.23
ASOS…………0.48

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HOURS ENDING 7 A.M………..0.3  DEPARTURE…..-0.2
TOTAL SNOWFALL FOR THE MONTH……………… 1.9  DEPARTURE…..-0.9
TOTAL SNOWFALL FOR THE SEASON……………..28.1  DEPARTURE…..+9.3

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 The low since midnight is 28F, 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 6
HIGH 66F IN 2007
LOW -14F IN 1896
PRECIP 3.10 INS. IN 1889 [RECORD FOR MONTH] SNOWFALL 7.5 INS. IN 1893
PEAK GUST 70 MPH WNW IN 1959

RECORDS FOR JANUARY 7
HIGH 60F IN 1930
LOW -8F IN 2018
PRECIP 1.97 INS. IN 1977
SNOWFALL 16.0 INS. IN 1977
PEAK GUST 74 MPH NW IN 1968

TODAY’S REPORT PREPARED BY: Benjamin Turner