Sunday, December 24, 2023

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

SUNDAY, DECEMBER 24, 2023
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0711E
SUNSET:  1616E

OVERCAST SKIES AND LIGHT WIND, BUT MILD FOR MID-LATE DECEMBER….

Skies have been cloudy all day today as we are stuck under an
inversion. Without any mixing of the atmosphere, it has been
a rather dank day with limited visibility and very light wind.

Temperatures are on the mild side however, with readings getting
into the mid 40s early this afternoon. The dew point has been on
the rise as well reaching the 40 degree mark by the 1pm observation.
Definitely not bad for those trying to get in some last minute
shopping today.

The wind has been quite light, even going calm early this afternoon.
The average speed so far for the day is only around 7mph. The
prevailing direction is out of the south-southeast. The peak gust
to this point has only been around 16mph, which occurred just before
1am.

Visibility as mentioned has been limited today, holding at around
30 miles, due to thin fog this morning, and haziness this afternoon.

The maximum temperature for today is 46F degrees, this is 8 degrees
above the normal high of 38F. The minimum temperature since midnight
is 35F degrees, this is 12 degrees above the normal low of 23F.

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Today’s Observations:

7 A.M.
Weather: Overcast altocumulus, few breaks in overcast OVHD-SW-W-N,
few stratocumulus distant WSW-NW and distant N-NNE
Temperature: 38F; Dew Point: 35F; Relative Humidity: 89%
Wind: SSE @ 6 kts, wind light
Sea-level pressure: 1031.1 mb; 30.45 in. Hg: rising, then steady
Visibility: 30 miles, thin fog
6-hr Max temp: 38F
6-hr Min temp: 35F
24-hr Precip:  0.00 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 E85 OVC 30 311/38/35/1606/045/ FEW BINOVC OVHD-SW-W-N
FEW SC DSNT WSW-NW AND DSNT N-NNE HIER CLDS VSBL OVHD-SW-W-N THN F ALQDS
WND LGT/ 8/57/ 51002 10038 20035

10 A.M.
Weather: Broken stratocumulus, overcast altocumulus/altostratus
Temperature: 40F; Dew Point: 38F; Relative Humidity: 93%
Wind: SSE @ 5 kts, wind light
Sea-level pressure: 1032.0 mb; 30.47 in. Hg: rising, then more rapidly
Visibility: 30 miles, thin fog
3-hr Precip:  0.00 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 E30 BKN 65 OVC 30 320/40/38/1605/047/ THN F ALQDS WND LGT/
8/57/ 53009

1 P.M.
Weather: Overcast stratocumulus, few lower stratocumulus distant SW
Temperature: 45F; Dew Point: 40F; Relative Humidity: 83%
Wind: Calm
Sea-level pressure: 1030.2 mb; 30.42 in. Hg: falling, then more rapidly
Visibility: 30 miles, hazy
6-hr Max temp: 46F
6-hr Min temp: 38F
6-hr Precip:  0.00 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 E30 OVC 30 302/45/40/0000/042/ FEW LWR SC DSNT SW HAZY
WND CALM/ 8/5// 58018 10046 20038

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SUMMARY FOR SATURDAY, DECEMBER 23, 2023

TEMPERATURE (DEGREES F)
MAX…….42   NORMAL…..38
MIN…….26   NORMAL…..23
MEAN……34   NORMAL…..31

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL………..+3
TOTAL DEPARTURE FOR THE MONTH…………………+103 [+4.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2023 THRU JUN 2024)
TOTAL HEATING UNITS FOR YESTERDAY……………31  DEPARTURE……..-3
TOTAL HEATING UNITS FOR THE MONTH…………..618  DEPARTURE……-104
TOTAL HEATING UNITS FOR THE SEASON…………1705  DEPARTURE……-221
TOTAL HEATING UNITS LAST SEASON TO DATE…….1646  DEPARTURE…….+59

PEAK WIND GUST (MPH):
Note: Instruments designated #1 = Main Tower, #2 = South Tower,
F420C, Contacting, Merlin, and Richards are all Main Tower.
E=Estimated

F420C (Official)……….E18 SSW  @  12:33 P.M.
VECTOR #1 (1-Sec)……….18 SSW  @  01:21 P.M.
VECTOR #2 (1-Sec)……….17 SSW  @  01:29 P.M.
DAVIS #1……………….17 S    @  01:14 P.M.
DAVIS #2 ………………19 S    @  12:02 P.M.
RMY #1 (Instantaneous)…..16 S    @  01:09 P.M.
RMY #2 (Instantaneous)…..18 SSW  @  01:29 P.M.
MERLIN…………………15 S
RICHARDS (C5C) (Inst)……16      @  01:32 P.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………11 S    @  07:24 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..12      @  12:06 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..12      @  01:40 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………12 S    @  01:31 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………14 S    @  06:51 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..12 S    @  12:06 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..13 SSW  @  01:40 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………12      @  12:06 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…….7.4 S [177 total miles] VECTOR #1……………..8.0
VECTOR #2……………..8.3
DAVIS #1………………M
DAVIS #2………………7.9 S
RMY #1………………..7.9 S
RMY #2………………..8.5 S
RICHARDS (C5C)…………8.3

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.17
TOTAL PRECIPITATION FOR THE MONTH…………..6.44 DEPARTURE…..+2.35
TOTAL PRECIPITATION FOR THE YEAR…………..57.81 DEPARTURE…..+5.25

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE……-0.5
TOTAL SNOWFALL FOR THE MONTH………………..0.3 DEPARTURE……-8.2
TOTAL SNOWFALL FOR THE SEASON (2023-2024)…….0.3 DEPARTURE…..-10.7

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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  51/38/45/+8/0.04/0.0/213/38         29 SW  VEC1 28 SW  RMY 29
12/2  48/43/46/+9/T/0.0/000/00            18 SSW VEC1 19 SSW RMY 19
12/3  44/41/43/+7/0.76/0.0/000/00         31 ENE VEC1 32 ENE RMY 33
12/4  49/37/43/+7/0.07/0.0/155/28         23 W   VEC1 22 W   RMY 23
12/5  38/28/33/-3/0.00/0.0/144/26         23 NNW VEC1 24 NW  RMY 24
12/6  34/22/28/-7/0.01/0.3/100/18         21 N   VEC1 21 N   RMY 20
12/7  28/17/56/-12/0.00/0.0/121/22        18 NNW VEC1 18 NW  RMY 19
12/8  42/24/33/-2/0.00/0.0/530/96         20 S   VEC1 18 S   RMY 18
12/9  52/33/43/+9/0.00/0.0/264/48         24 S   VEC1 24 S   RMY 24
12/10 60/43/52/+18/0.66/0.0/033/06        55 SSW VEC1 54 SSW RMY 53
12/11 61/33/47/+13/1.96/0.0/038/07        69 SSW VEC1 69 SSW RMY 71
12/12 42/29/36/+2/0.00/0.0/543/99         33 WNW VEC1 32 WNW RMY 34
12/13 43/28/36/+3/0.00/0.0/470/86         36 WNW VEC1 34 WNW RMY 36
12/14 34/22/28/-5/0.00/0.0/520/95         31 SW  VEC1 31 SW  RMY 32
12/15 53/30/42/+9/0.00/0.0/541/99         31 WNW VEC1 30 WNW RMY 28
12/16 50/36/43/+11/0.00/0.0/530/97        21 ESE VEC1 22 ESE RMY 22
12/17 55/37/46/+14/0.47/0.0/098/18        40 SSE VEC1 41 SSE RMY 41
12/18 61/42/52/+20/2.47/0.0/000/00        90 SSE VEC1 95 SSE RMY 101
12/19 46/30/38/+6/0.00/0.0/332/61         28 NW  VEC1 28 NW  RMY 26
12/20 41/26/34/+3/0.00/0.0/540/99         26 NNW VEC1 27 NNW RMY 28
12/21 34/20/27/-4/0.00/0.0/534/98         29 NNW VEC1 30 NNW RMY 28
12/22 34/16/25/-6/0.00/0.0/…/..         18 NNW VEC1 18 NNW RMY 19
12/23 42/26/34/+3/0.00/0.0/…/..         18 SSW VEC1 18 SSW RMY 16

12/24 The low since midnight is 35F, the daily normal low is 23F

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DECEMBER DAILY RECORDS TO DATE

12/18: RECORD MAXIMUM TEMPERATURE OF 61F;
BEATS OLD RECORD OF 59F SET IN 1928

12/18: RECORD PRECIPITATION OF 2.47 INS;
BEATS OLD RECORD OF 1.44 INS SET IN 1915

12/18: RECORD PEAK WIND GUST OF 90 MPH;
BEATS OLD RECORD OF 76e MPH SET IN 1978

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

RECORDS FOR DECEMBER 24
HIGH 67 IN 2015
LOW -6 IN 1943
PRECIP 2.21 INS. IN 1994
SNOWFALL 12.3 INS. IN 1961
PEAK GUST 79e MPH SE IN 1941

RECORDS FOR DECEMBER 25
HIGH 64 IN 2015
LOW -11 IN 1980
PRECIP 2.15 INS. IN 2020
SNOWFALL 8.5 INS. IN 2002
PEAK GUST 80 MPH NW IN 1971

TODAY’S REPORT PREPARED BY: Matt Douglas