Sunday, December 6, 2020

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

SUNDAY, DECEMBER 6, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

A NICE WEATHER DAY FOLLOWING SOME OVERNIGHT SNOW
ATOP GREAT BLUE HILL….

The snow total for last night’s event is 2.8 inches!
Rain changed over to snow around 4 PM yesterday, and
continued to a little past midnight, giving us a
trace of snow this morning. The liquid precipitation
amount for the rain and snow yesterday amounted to
2.20 inches, bringing us back to normal for annual
rainfall.

Visibility has been amazing today at 90 miles. From
the top of the tower, the observer is able to see
the snowy top of Mount Monadnock very clearly.
Wachusett in western Massachusetts can also be seen
40 miles away.

Wind is another main feature of the day, being strong
from the northwest. The average speed is 20 mph, with
a max gust of 41 being seen this morning.

The high so far today is 34F, 8 degrees below the daily
normal high of 42F. The low since midnight is 28F,
a degree above the normal low of 27F.

PRELIMINARY STATS FOR NOVEMBER 2020

TEMPERATURE, Deg. F
Avg. Max. 56.3 [+6.3] Avg. Min. 38.6 [+5.1] Mean      47.5 [+5.8] 24-hour corrected mean: 46.9
Max. for month: 75F on the 7th
Min. for month: 18F on the 19th

HEATING DEGREE DAYS
Total heating units:   521 [-177] Total for the season:  973 [-288] Total for last season: 1237

PRECIPITATION, Inches
Total: 5.23 [+1.77] Greatest in 24 hrs: N/A

SNOWFALL, Inches
Total: TRACE
Greatest in 24 hrs: T on the 2nd

WIND, mph
Avg. uncorrected wind speed: 12.9 mph
Avg. corrected wind speed:   13.2 mph
Prevailing wind direction:   SSW [14%] Peak gust and direction:     81 SSE on the 30th

SUNSHINE:
Campbell-Stokes card minutes: N/A
Astronomical total minutes: N/A

Today’s Observations:

7 A.M.
Weather: Scattered cumulus and broken cirrus
Temperature: 28F; Dew Point: 23F; Relative Humidity: 82%
Wind: WNW at 17G36 kts, peak of 41 mph at 6:49 A.M.
Sea-level pressure: 29.58 in Hg; rising, then more
rapidly
Visibility: 60 miles
6-hr Max temp: 32F
6-hr Min temp: 28F
24-hr Precip: 1.83 ins.
24-hr Snow: 2.8 ins.
Snow Depth: 2 ins.
BHO SA 1155 40 SCT 250 BKN 60 016/28/23/3017G36/958/ NEW
SNOW PAST 24 HRS 2.8 INS. PK WND 3236/49/ 8/801 4/002 70183
51023 10032 20028

10 A.M.
Weather: Scattered altocumulus, broken cirrostratus
Temperature: 31F; Dew Point: 23F; Relative Humidity: 73%
Wind: WNW at 19G28 kts, peak of 37 mph at 8:21 A.M.
Sea-level pressure: 29.60 in Hg; falling then rising
Visibility: 85 miles
3-hr Precip: 0.00 ins.
3-hr Snow: 0.0 ins.
BHO SA 1455 140 SCT 250 BKN 85 027/31/23/3019G28/960/ PK
WND 2932/1321/ 8/086 50011

1 P.M.
Weather: Broken cumulus and cirrostratus
Temperature: 34F; Dew Point: 23F; Relative Humidity: 64%
Wind: WNW at 13G26 kts, peak of 35 mph at 12:52 P.M.
Sea-level pressure: 29.58 in Hg; falling steadily
Visibility: 90 miles
6-hr Max temp: 34F
6-hr Min temp: 28F
6-hr Precip: 0.00 ins.
6-hr Snow: 0.0 ins.
Snow Depth:  2 ins.
BHO SA 1755 40 BKN 250 BKN 90 020/34/23/3013G26/958/ PK WND
2929/52/ 8/106 4/002 56007 10034 20028

SUMMARY FOR SATURDAY, DECEMBER 5, 2020

TEMPERATURE (DEGREES F)
MAX…….42   NORMAL…..43
MIN…….32   NORMAL…..27
MEAN……37   NORMAL…..35

DEPARTURE FROM 30-YEAR NORMAL………………. +2
TOTAL DEPARTURE FOR THE MONTH………………. +37 [+7.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………28  DEPARTURE…….-2
TOTAL HEATING UNITS FOR THE MONTH…………..111  DEPARTURE……-35
TOTAL HEATING UNITS FOR THE SEASON…………1084  DEPARTURE…..-324
TOTAL HEATING UNITS LAST SEASON TO DATE…….1418  DEPARTURE…..-334

PEAK WIND GUST FOR YESTERDAY (MPH):
420C/Official…………..58 NNW  AT  3:57 P.M.
AEROVANE (south tower)…..58 NNW  AT  3:57 P.M.
ASOS…………………..58 NNW  AT  4:09 P.M.
DAVIS #1……………….51 NNE  AT  4:42 P.M.
DAVIS #2 (south tower)…..51 NNE  AT  4:42 P.M.
RMY……………………67
VECTOR…………………69
MERLIN…………………53

FASTEST MILE FOR YESTERDAY:
CONTACTING/OFFICIAL………………………..34 NNW  AT   4:08 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….35 NNW  AT   4:09 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………37 NNW  AT   3:46 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………37 NNW  AT   3:46 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……18.0 N    [432 total miles] ASOS…………………17.5      [420 total miles] DAVIS #1……………..17.9 NNW  [430 total miles] DAVIS #2……………..17.9 NNW  [430 total miles] RMY………………….17.1 N    [411 total miles] VECTOR……………….17.5      [413 total miles]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….1.83  DEPARTURE….+1.66
ASOS………….1.89
TOTAL PRECIPITATION FOR THE MONTH………….2.81  DEPARTURE….+1.99
ASOS………….2.89
TOTAL PRECIPITATION FOR THE YEAR………….47.38  DEPARTURE….-0.14
ASOS………..48.33

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HOURS ENDING 7 A.M………..2.8  DEPARTURE…..+2.5
TOTAL SNOWFALL FOR THE MONTH……………….2.8  DEPARTURE…..+1.4
TOTAL SNOWFALL FOR THE SEASON………………9.3  DEPARTURE…..+5.3

PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER 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

11/01   49/36/43/-3/0.69/0.0/006/01      38 W     AERO 40 W    RMY 39
11/02   40/31/36/-10/T/T/425/69          61 WNW   AERO 62 WNW  RMY 62
11/03   43/29/36/-10/0.00/0.0/473/77     48 WNW   AERO 53 WNW  RMY 48
11/04   54/30/42/-3/0.00/0.0/550/90      30 SSW   AERO 30 SSW  RMY 30
11/05   69/49/59/+14/0.00/0.0/548/90     37 SSW   AERO 40 SSW  RMY 38
11/06   72/55/64/+19/0.00/0.0/394/65     28 SW    AERO 28 SW   RMY M
11/07   75/54/65/+20/0.00/0.0/562/93     21 WSW   AERO 21 WSW  RMY 21
11/08   73/54/64/+20/0.00/0.0/584/97     18 W     AERO 18 W    RMY 19
11/09   74/52/63/+19/0.00/0.0/593/99     20 WSW   AERO 18 WSW  RMY 21
11/10   74/53/64/+20/0.00/0.0/597/100    30 SW    AERO 28 SW   RMY 31
11/11   73/58/66/+23/0.04/0.0/137/23     40 SW    AERO 44 SW   RMY 45
11/12   64/46/55/+12/0.04/0.0/000/00     32 NNW   AERO 31 NNW  RMY 33
11/13   48/38/43/0/0.30/0.0/000/00       22 NW    AERO 21 NW   RMY 25
11/14   49/32/41/-1/0.00/0.0/276/47      26 NW    AERO 28 NW   RMY 29
11/15   58/30/44/+2/0.62/0.0/311/53      60 S     AERO 67 S    RMY 65
11/16   53/39/46/+4/0.00/0.0/526/90      40 WNW   AERO 41 WNW  RMY 43
11/17   47/32/40/-1/0.00/0.0/204/35      28 NW    AERO 28 NW   RMY 30
11/18   32/19/26/-15/0.00/0.0/580/100    40 NW    AERO 46 NW   RMY 43
11/19   44/18/31/-10/0.00/0.0/393/68     37 SW    AERO 39 SW   RMY 43
11/20   63/44/54/+14/0.00/0.0/495/86     33 SSW   AERO 35 SSW  RMY 37
11/21   62/40/51/+11/0.00/0.0/339/59     24 W     AERO 23 W    RMY 27
11/22   45/33/39/-1/T/0.0/006/01         28 SE    AERO 28 SE   RMY 31
11/23   58/32/45/+6/1.77/0.0/000/00      42 WNW   AERO 48 WNW  RMY 46 TSTM
11/24   42/27/35/-4/0.00/0.0/569/100     31 WNW   AERO 32 WNW  RMY 33
11/25   50/26/38/-1/0.01/0.0/017/03      23 SSE   AERO 23 SSE  RMY 26
11/26   58/45/52/+14/0.36/0.0/000/00     36 S     AERO 37 S    RMY 41
11/27   53/46/50/+12/0.00/0.0/056/10     23 WNW   AERO 23 WNW  RMY 23
11/28   52/36/44/+6/T/0.0/180/32         28 WNW   AERO 30 WNW  RMY 27
11/29   52/33/43/+6/0.00/0.0/561/100     21 SSW   AERO 21 SSW  RMY 22
11/30   62/40/51/+14/1.35/0.0/000/00     81 SSE   AERO 82 SSE  RMY 86

DAILY RECORDS FOR NOVEMBER 2020

11/06/20: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 72F,
BREAKS PREVIOUS RECORD OF 71F SET IN 1959 AND 2015

11/07/20: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 75F,
TIES PREVIOUS RECORD OF 75F SET IN 1938

11/08/20: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 73F,
BREAKS PREVIOUS RECORD OF 72F SET IN 1938

11/09/20: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 74F,
BREAKS PREVIOUS RECORD OF 72F SET IN 1975

11/11/20: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 58F,
BREAKS PREVIOUS RECORD OF 56F IN 2002
DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 73F,
BREAKS PREVIOUS RECORD OF 68F IN 1984

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/…./…/…/..      35 SSW  AERO 35 SSW  RMY 37
12/05   42/32/37/+2/…./2.8/…/..       58 NNW  AERO 58 NNW  RMY 67

12/06 The low since midnight is 28F, the daily normal low is 27F

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

RECORDS FOR DECEMBER 6
HIGH 70 IN 2001
LOW 5 IN 1901,1935
PRECIP 2.78 INS. IN 2003
SNOWFALL 17.0 INS. IN 2003
PEAK GUST 74 MPH NW IN 1981

RECORDS FOR DECEMBER 7
HIGH 74 IN 1998
LOW 6 IN 1906
PRECIP 1.67 INS. IN 1953
SNOWFALL 6.3 INS. IN 2003
PEAK GUST 76e SE IN 1976

TODAY’S REPORT PREPARED BY: Benjamin Turner