Wednesday, December 17, 2025
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
WEDNESDAY, DECEMBER 17, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0708E
SUNSET: 1613E
EARLY MORNING SUNSHINE REPLACED BY A DECK OF LOW CLOUDS….
We started the day with mainly clear skies and a good deal of
sunshine, but by mid morning a deck of low clouds overspread
the area and have been overhead into early this afternoon.
Despite the cloud cover, temperatures have been able to warm up
nicely. Readings have reached the low 40s, and believe it or not,
this is finally above normal! Dew point values have been slowly
coming up as well, rising from the upper teens to the mid 20s over
the course of the day.
The wind has been on the busy side today. The average speed for
the day so far is around 19mph. Gusts have been frequently
exceeding 30mph. The peak gust for the day so far is 42mph,
which occurred just after 10:30am this morning.
Visibility has been somewhat limited today due to haziness. The
view has generally been holding around 30-40 miles all day.
The maximum temperature so far today is 41F degrees, which is
1 degree above the normal high of 40F. The minimum temperature
since midnight is 25F degrees, which is equal to the normal low
of 25F.
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Today’s Observations:
7 A.M.
Weather: Thin scattered cirrus
Temperature: 29F; Dew Point: 19F; Relative Humidity: 65%
Wind: SSW @ 20G32 kts, peak wind SSW 37mph at 6:45 A.M.
Sea-level pressure: 1013.6 mb; 29.93 in. Hg: faling, then more rapidly
Visibility: 30 miles, hazy
6-hr Max temp: 29F
6-hr Min temp: 25F
24-hr Precip: 0.00 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 1 inch
BHO SA 1155 250 -SCT 30 136/29/19/2120G32/993/ HAZY PK WND 2132/45/
8/001 4/001 58021 10029 20025
10 A.M.
Weather: Overcast stratocumulus, few breaks in overcast distant ESE-SSE
Temperature: 37F; Dew Point: 23F; Relative Humidity: 56%
Wind: SW @ 18G29 kts, peak wind SW 33mph at 9:45 A.M.
Sea-level pressure: 1013.0 mb; 29.91 in. Hg: falling, then rising
Visibility: 30 miles, hazy
3-hr Precip: 0.00 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 E30 OVC 30 130/37/23/2318G29/991/ FEW BINOVC DSNT ESE-SSE
HAZY PK WND 2229/45/ 8/5// 55006
1 P.M.
Weather: Broken stratocumulus, broken cirrus
Temperature: 41F; Dew Point: 26F; Relative Humidity: 54%
Wind: SW @ 15G24 kts
Sea-level pressure: 1009.5 mb; 29.81 in. Hg: falling, then more slowly
Visibility: 40 miles, hazy
6-hr Max temp: 41F
6-hr Min temp: 29F
6-hr Precip: 0.00 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 1 inch
BHO SA 1755 E40 BKN 250 BKN 40 095/41/26/2215G24/981/ HAZY/
8/501 4/001 56035 10041 20029
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SUMMARY FOR TUESDAY, DECEMBER 16, 2025
TEMPERATURE (DEGREES F)
MAX…….36 NORMAL…..40
MIN…….19 NORMAL…..25
MEAN……28 NORMAL…..32
DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….-4
TOTAL DEPARTURE FOR THE MONTH……………………..-116 [-7.5 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)
TOTAL HEATING UNITS FOR YESTERDAY…………….37 DEPARTURE……..+4
TOTAL HEATING UNITS FOR THE MONTH……………602 DEPARTURE……+115
TOTAL HEATING UNITS FOR THE SEASON………….1719 DEPARTURE…….+29
TOTAL HEATING UNITS LAST SEASON TO DATE……..1456 DEPARTURE……+263
PEAK WIND GUST (MPH):
Note: Instruments designated #1 = Main Tower, #2 = South Tower,
F420C, Contacting, Merlin, and Richards are all on Main Tower.
E=Estimated *=Last of multiple occurrences
F420C (Official)………..29 SW @ 10:59 P.M.
VECTOR #1 (1-Sec)……….29 SW @ 10:59 P.M.
VECTOR #2 (1-Sec)……….28 SW @ 11:28 P.M.
DAVIS #1……………….29 SW @ 10:59 P.M.
DAVIS #2 ………………28 WSW @ 11:28 P.M.
RMY #1 (Instantaneous)…..30 SW @ 10:59 P.M.
RMY #2 (Instantaneous)…..28 SW @ 10:59 P.M.
MERLIN………………….M
RICHARDS (C5C) (Inst)……32 SW @ 11:28 P.M.
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………23 SW @ 10:45 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..21 SW @ 11:01 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..21 SW @ 11:28 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………21 SW @ 11:01 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………21 SW @ 11:01 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..21 SW @ 11:01 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..21 SW @ 11:01 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………19 SW @ 11:01 P.M.
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………9.8 W [236 total miles]
VECTOR #1………………10.1
VECTOR #2………………10.3
DAVIS #1……………….10.0 SW
DAVIS #2……………….10.1 SW
RMY #1………………….9.9 SW
RMY #2…………………10.2 SW
RICHARDS (C5C)…………..9.7
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.18
TOTAL PRECIPITATION FOR THE MONTH…………..1.08 DEPARTURE…..-1.78
TOTAL PRECIPITATION FOR THE YEAR (2025)…….45.54 DEPARTURE…..-5.79
SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE…..-0.4
TOTAL SNOWFALL FOR THE MONTH………………..2.4 DEPARTURE…..-2.9
TOTAL SNOWFALL FOR THE SEASON (2025-2026)…….2.5 DEPARTURE…..-5.3
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PRELIMINARY CLIMATE SUMMARY FOR DECEMBER CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN)/SUN(%)/PEAK GUST/VEC1/RMY GUST
PEAK GUST: F420C (Official)
VEC1: Vector #1 1-second gust
RMY: R.M. Young #1 wind gust recording system (Instantaneous)
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized
M: Missing data
12/1 42/27/35/-2/T/0.0/547/98 37 WNW VEC1 37 WNW RMY 38
12/2 36/27/32/-5/0.85/T/000/00 38 N VEC1 38 NNE RMY 38
12/3 37/27/32/-4/0.06/0.6/423/76 28 NW VEC1 29 NNW RMY 30
12/4 38/15/27/-9/T/T/255/46 60 NW VEC1 59 WNW RMY 61
12/5 25/8/17/-19/T/T/510/92 30 NW VEC1 30 NW RMY 30
12/6 39/25/32/-3/T/T/122/22 21 W VEC1 21 W RMY 22
12/7 39/27/33/-2/0.00/0.0/248/45 24 W VEC1 24 W RMY 24
12/8 31/12/22/-13/T/T/457/83 43 NW VEC1 43 NW RMY 44
12/9 28/9/19/-15/0.00/0.0/452/82 33 SSW VEC1 33 SSW RMY 33
12/10 46/28/37/+3/0.04/T/187/34 50 SSW VEC1 50 SSW RMY 51
12/11 37/21/29/-5/0.00/0.0/450/82 51 WNW VEC1 51 WNW RMY 53
12/12 33/18/26/-8/0.00/0.0/532/97 41 W VEC1 41 W RMY 42
12/13 34/23/29/-4/0.00/0.0/038/07 28 SW VEC1 28 SW RMY 31
12/14 31/15/23/-10/0.13/1.8/000/00 39 NNW VEC1 39 NNW RMY 40
12/15 23/10/17/-16/0.00/0.0/…/.. 40 NW VEC1 40 NW RMY 42
12/16 36/19/28/-4/0.00/0.0/…/.. 29 SW VEC1 29 SW RMY 30
12/17 The low since midnight is 25F, the daily normal low is 25F.
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DECEMBER DAILY RECORDS TO DATE
NONE.
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DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR DECEMBER 17
HIGH 63 IN 2000
LOW -9 IN 1942
PRECIP 3.03 INS. IN 1888
SNOWFALL 15.1 INS. IN 2020
PEAK GUST 78 MPH SSE IN 2000
RECORDS FOR DECEMBER 18
HIGH 61 IN 2023
LOW -11 IN 1919
PRECIP 2.47 INS. IN 2023
SNOWFALL 7.0 INS. IN 1904
PEAK GUST 90 SSE IN 2023
TODAY’S REPORT PREPARED BY: Matt Douglas
