Tuesday, December 10, 2024

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

TUESDAY, DECEMBER 10, 2024
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0703E
SUNSET:  1612E

PERIODS OF RAIN OVERNIGHT; TEMPERATURE DROP EARLY THIS MORNING WITH
FREEZING DRIZZLE ON THE SUMMIT….

We got a pretty good dose of rainfall overnight as a low pressure
system passed by the region. Rain began just after 3pm yesterday
afternoon with the heaviest falling during the evening hours. Lighter
rain continued after midnight before tapering to drizzle between
3-4am this morning. Drizzle has continued through the morning, finally
ending just after noon. It was mainly on the very light side. However,
the temperature dropped to or just under freezing by 6am with some
very light icing taking place on mainly elevated surfaces through the
morning hours. There is still a thin glaze of ice one some surfaces
early this afternoon. Some of our wind systems are frozen and
inoperable at this time.

As mentioned, the temperature dropped early this morning to or just
below freezing, where it has been hovering since. It was in the low 40s
around midnight, which is the high for the day so far.

Winds were gusty in the wee hours of this morning, but then diminished
rapidly by the mid morning hours. The average speed for the day so far
is around 10mph, but it’s been generally around 6mph for the past few
hours. The peak gust so far for the day is 31mph, which occurred at
1:05am this morning.

Visibility has been very limited today as we’ve spent the day in the
clouds. 1/16th of a mile is the best we’ve been able to do all day.

The maximum temperature for today is 42F degrees, which is equal to
the normal high of 42F. The minimum temperature since midnight is 31F
degrees, which is 4 degrees above the normal low of 27F.

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Today’s Observations:

7 A.M.
Weather: Sky obscured, vertical visibility 200ft, very light drizzle
Temperature: 31F; Dew Point: 31F; Relative Humidity: 100%
Wind: N @ 9G16 kts
Sea-level pressure: 1020.5 mb; 30.14 in. Hg: rising, then more rapidly
Visibility: 1/16 mile, fog
6-hr Max temp: 41F
6-hr Min temp: 31F
24-hr Precip:  0.54 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 X W2 1/16L-F 205/31/31/3609G16/014/ PCPN VRY LGT/
8//// 53019 6010/ 70054 10041 20031

10 A.M.
Weather: Sky obscured, vertical visibility 100ft, very light drizzle/
freezing drizzle, thin glaze on some surfaces
Temperature: 32F; Dew Point: 32F; Relative Humidity: 100%
Wind: N @ 6 kts, wind light
Sea-level pressure: 1022.1 mb; 30.18 in. Hg: steady, then rising
Visibility: 1/16 mile, fog
3-hr Precip:  0.01 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 X W1 1/16L-ZL-F 221/32/32/3606/018/ PCPN VRY LGT
SLGT GLZG ON SOME SFCS WND LGT/ 8//// 53016 6001/

1 P.M.
Weather: Sky obscured, vertical visibility 100ft, thin glaze on some
surfaces
Temperature: 32F; Dew Point: 32F; Relative Humidity: 100%
Wind: NNE @ 5 kts, wind light
Sea-level pressure: 1020.7 mb; 30.14 in. Hg: falling, then more rapidly
Visibility: 1/16 mile, fog
6-hr Max temp: 33F
6-hr Min temp: 31F
6-hr Precip:  0.01 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 X W1 1/16F 207/31/31/0305/014/ L-ZL-E08 THN GLZ ON SOME
SFCS WND LGT/ 8//// 58014 6001/ 10033 20031

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SUMMARY FOR MONDAY, DECEMBER 9, 2024

TEMPERATURE (DEGREES F)
MAX…….47  NORMAL…..42
MIN…….34  NORMAL…..27
MEAN……41  NORMAL…..34

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………..+7
TOTAL DEPARTURE FOR THE MONTH…………………….-32 [-3.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY……………24  DEPARTURE……..-7
TOTAL HEATING UNITS FOR THE MONTH…………..296  DEPARTURE…….+32
TOTAL HEATING UNITS FOR THE SEASON…………1239  DEPARTURE……-229
TOTAL HEATING UNITS LAST SEASON TO DATE…….1335  DEPARTURE…….-96

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

F420C (Official)………..28 ENE  @   11:16 P.M.
VECTOR #1 (1-Sec)……….28 E    @   08:16 P.M.
VECTOR #2 (1-Sec)……….30 E    @   08:40 P.M.
DAVIS #1……………….28 E    @   11:16 P.M.
DAVIS #2 ………………30 SE   @   08:40 P.M.
RMY #1 (Instantaneous)…..29 ENE  @   10:29 P.M.
RMY #2 (Instantaneous)…..30 E    @   08:40 P.M.
MERLIN………………….M
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………21 ENE  @   09:53 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..20      @   05:17 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..21      @   11:17 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………21 E    @   05:17 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………21 E    @   11:34 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..20 E    @   05:17 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..21 E    @   05:17 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………9.3 E  [223 total miles] VECTOR #1……………….9.2
VECTOR #2……………….9.7
DAVIS #1………………..9.7 ESE
DAVIS #2………………..9.5 E
RMY #1………………….9.3 ESE
RMY #2………………….9.6 E
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.54 DEPARTURE…..+0.36
TOTAL PRECIPITATION FOR THE MONTH…………..1.09 DEPARTURE…..-0.52
TOTAL PRECIPITATION FOR THE YEAR (2024)…….48.56 DEPARTURE…..-1.52

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE……-0.4
TOTAL SNOWFALL FOR THE MONTH………………..3.0 DEPARTURE……+0.4
TOTAL SNOWFALL FOR THE SEASON (2024-2025)…….3.0 DEPARTURE……-2.1

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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   37/23/30/-7/0.00/0.0/452/81        21 WSW VEC1 21 WSW RMY 21
12/2   38/22/30/-7/0.00/0.0/551/99        18 W   VEC1 18 W   RMY 18
12/3   36/20/28/-8/0.00/0.0/411/74        21 NW  VEC1 21 WNW RMY 21
12/4   39/22/31/-5/0.13/T/394/71          30 S   VEC1 31 S   RMY 33
12/5   37/31/34/-2/0.40/3.0/…/..        43 WNW VEC1 43 WNW RMY 47
12/6   31/23/27/-8/0.00/0.0/…/..        39 NW  VEC1 39 W   RMY 42
12/7   37/22/30/-5/T/T/…/..             25 S   VEC1 25 S   RMY 26
12/8   47/28/38/+3/0.02/T/…/..          37 SSW VEC1 37 SSW RMY 40
12/9   47/34/41/+7/0.41/0.0/…/..        28 ENE VEC1 28 E   RMY 29

12/10 The low since midnight is 31F, the daily normal low is 27F.

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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 10
HIGH 62 IN 1946
LOW -6 IN 1902
PRECIP 1.67 INS. IN 1907
SNOWFALL 6.0 INS. IN 1905
PEAK GUST 66e SW IN 1940

RECORDS FOR DECEMBER 11
HIGH 63 IN 1911
LOW -1 IN 1988
PRECIP 2.36 INS. IN 1992
SNOWFALL 4.8 INS. IN 2019
PEAK GUST 78 S IN 1969

TODAY’S REPORT PREPARED BY: Matt Douglas