Thursday, January 7, 2021
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
THURSDAY, JANUARY 7, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
A SIMILAR DAY TO YESTERDAY, BUT WITH GOOD
VISIBILITY AT THE START….
Today we observed partly cloudy skies, with
a good average visibility of 70 miles. The
highest visibility was 75 miles at 10 A.M.
Conditions are on the drier side, with dew
points in the upper teens and a humidity of
44% at the 1 P.M. observation. Wind is
consistent at a little over 10 mph, with
frequent gusts around 20 mph from the
northwest.
The high so far today is 39F, 5 degrees above
the daily normal maximum of 34F. The low since
midnight is 28F, 10 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: N/A
Astronomical total minutes: N/A
Today’s Observations:
7 A.M.
Weather: Scattered altocumulus and cirrostratus
Temperature: 29F; Dew Point: 17F; Relative Humidity: 61%
Wind: NW at 10G19 kts
Sea-level pressure: 29.97 in Hg; rising steadily
Visibility: 65 miles, thin fog
6-hr Max temp: 29F
6-hr Min temp: 28F
24-hr Precip: 0.00 ins.
24-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1155 65 SCT 250 SCT 65 149/29/17/3210G19/997/ 8/088
53008 10029 20028
10 A.M.
Weather: Scattered altocumulus and cirrostratus
Temperature: 32F; Dew Point: 17F; Relative Humidity: 54%
Wind: NW at 15G20 kts
Sea-level pressure: 30.01 in Hg; falling, then rising
Visibility: 75 miles
3-hr Precip: 0.00 ins.
3-hr Snow: 0.0 ins.
BHO SA 1455 140 SCT 250 SCT 75 163/32/17/3215G20/001/ 8/088
51014
1 P.M.
Weather: Scattered altocumulus, broken cirrus
Temperature: 39F, Dew point: 19F; Relative Humidity: 44%
Wind: WNW at 9 kts
Sea-level pressure: 29.97 inches Hg, falling, then more slowly
Visibility: 70 miles
6-hr Max temp: 39F
6-hr Min temp: 28F
6-hr Precip: 0.00 ins.
6-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1755 140 SCT 250 SCT 70 150/39/19/3009/997/ 8/084 56013
10039 20028
SUMMARY FOR WEDNESDAY, JANUARY 6, 2021
TEMPERATURE (DEGREES F)
MAX…….38 NORMAL…..34
MIN…….28 NORMAL…..18
MEAN……33 NORMAL…..26
DEPARTURE FROM 30-YEAR NORMAL…………………+7
TOTAL DEPARTURE FOR THE MONTH…………………+36 [+5.8 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………32 DEPARTURE…… -7
TOTAL HEATING UNITS FOR THE MONTH…………..196 DEPARTURE……-36
TOTAL HEATING UNITS FOR THE SEASON…………2126 DEPARTURE…..-410
TOTAL HEATING UNITS LAST SEASON TO DATE…….2427 DEPARTURE…..-301
PEAK WIND GUST FOR YESTERDAY (MPH):
420C/Official…………..30 NW @ 5:27 P.M.
AEROVANE (south tower)…..29 NW @ 4:48 P.M.
ASOS…………………..30 N @ 5:28 P.M.
DAVIS #1……………….29 NW @ 5:27 P.M.
DAVIS #2 (south tower)…..29 NW @ 4:48 P.M.
RMY……………………32
VECTOR…………………33
MERLIN…………………32
FASTEST MILE FOR YESTERDAY:
CONTACTING/OFFICIAL………………………..21 NW @ 5:28 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….22 NW @ 5:28 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………29 NW @ 5:28 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………22 NW @ 5:28 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..22 NNW @ 5:25 P.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE……………..22 @ 5:28 P.M.
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…12.7 NW [304 total miles]
ASOS………………12.8 [229 total miles]
DAVIS #1…………..13.0 NNW [231 total miles]
DAVIS #2…………..12.8 NNW [229 total miles]
RMY……………….12.2 NNW [293 total miles]
VECTOR…………….12.8 [229 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….-0.37
ASOS………….0.48
TOTAL PRECIPITATION FOR THE YEAR…………..0.49 DEPARTURE….-0.37
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…..-1.5
TOTAL SNOWFALL FOR THE SEASON……………..28.1 DEPARTURE…..+8.7
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 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 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
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
TODAY’S REPORT PREPARED BY: Benjamin Turner