Friday, December 22, 2023

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

FRIDAY, DECEMBER 22, 2023
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0710E
SUNSET:  1615E

A WINTER FEEL UNDER COLD SUNSHINE, BUT LIGHT WIND….

Plenty of bright sunshine is the theme today, but the temperature
has once again struggled into the low 30s today. The air is very
dry with a dew point that’s been hanging out in the lower teens,
so it’s adding a decided chill to the air for sure.

On the bright side, the wind hasn’t been much of a factor since
early this morning. A northwest to north-northwesterly wind has
been decreasing as the day progresses. The average speed for the
day is around 7mph, but has only averaged about 3mph or so over
the past couple of hours. The peak gust for the day was just
before 1am at around 18mph.

Visibility has been excellent all day, ranging between 70-80 miles.

The maximum temperature for today is 33F degrees, this is 6 degrees
below the normal high of 39F. The minimum temperature since midnight
is 16F degrees, this is 7 degrees below the normal low of 23F.

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Today’s Observations:

7 A.M.
Weather: Clear, few stratocumulus offshore distant ENE-SE, few cirrus
distant SSE-W-NW
Temperature: 17F; Dew Point: 11F; Relative Humidity: 77%
Wind: NW @ 6 kts, wind light
Sea-level pressure: 1031.5 mb; 30.46 in. Hg: rising, then more rapidly
Visibility: 70 miles
6-hr Max temp: 20F
6-hr Min temp: 16F
24-hr Precip:  0.00 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 CLR 70 315/17/11/3206/046/ FEW SC OFFSHR DSNT ENE-SE
FEW CI DSNT SSE-W-NW/ 8/501 53011 10020 20016

10 A.M.
Weather: Thin broken cirrus, few stratocumulus offshore distant ENE-SE
Temperature: 25F; Dew Point: 13F; Relative Humidity: 60%
Wind: NW @ 5 kts, wind light
Sea-level pressure: 1032.7 mb; 30.50 in. Hg: rising, then more slowly
Visibility: 80 miles
3-hr Precip:  0.00 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 E250 -BKN 80 327/25/13/3205/050/ FEW SC OFFSHR DSNT ENE-SE
WND LGT/ 8/501 51012

1 P.M.
Weather: Thin scattered cirrus, few stratocumulus offshore distant E-SE
Temperature: 32F; Dew Point: 11F; Relative Humidity: 41%
Wind: NW @ 3 kts, wind light and variable
Sea-level pressure: 1031.2 mb; 30.45 in. Hg: falling, then more rapidly
Visibility: 80 miles
6-hr Max temp: 33F
6-hr Min temp: 17F
6-hr Precip:  0.00 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 250 -SCT 80 312/32/11/3203/045/ FEW SC OFFSHR DSNT E-SE
WND L/V/ 8/501 58015 10033 20017

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SUMMARY FOR THURSDAY, DECEMBER 21, 2023

TEMPERATURE (DEGREES F)
MAX…….34   NORMAL…..39
MIN…….20   NORMAL…..24
MEAN……27   NORMAL…..31

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL………..-4
TOTAL DEPARTURE FOR THE MONTH…………………+106 [+4.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2023 THRU JUN 2024)
TOTAL HEATING UNITS FOR YESTERDAY……………38  DEPARTURE……..+4
TOTAL HEATING UNITS FOR THE MONTH…………..547  DEPARTURE……-106
TOTAL HEATING UNITS FOR THE SEASON…………1634  DEPARTURE……-223
TOTAL HEATING UNITS LAST SEASON TO DATE…….1587  DEPARTURE…….+47

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)……….E29 NNW  @  11:57 A.M.
VECTOR #1 (1-Sec)……….30 NNW  @  09:31 A.M.
VECTOR #2 (1-Sec)……….29 NNW  @  09:32 A.M.
DAVIS #1……………….28 NNW  @  09:31 A.M.
DAVIS #2 ………………27 N    @  09:32 A.M.
RMY #1 (Instantaneous)…..28 NNW  @  07:40 A.M.
RMY #2 (Instantaneous)…..28 NNW  @  09:32 A.M.
MERLIN…………………25 NNW
RICHARDS (C5C) (Inst)……26      @  11:57 A.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………18 NNW  @  09:37 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..19      @  09:36 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..19      @  09:35 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………18 NNW  @  09:36 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………19 N    @  09:36 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..18 NNW  @  09:36 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..19 NNW  @  09:32 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………18      @  09:36 A.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……12.0 NNW [287 total miles] VECTOR #1…………….11.7
VECTOR #2…………….12.0
DAVIS #1……………..11.9 NNW
DAVIS #2……………..12.0 N
RMY #1……………….11.4 NNW
RMY #2……………….11.9 NNW
RICHARDS (C5C)………..12.0

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.18
TOTAL PRECIPITATION FOR THE MONTH…………..6.44 DEPARTURE…..+2.70
TOTAL PRECIPITATION FOR THE YEAR…………..57.81 DEPARTURE…..+5.60

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……-7.3
TOTAL SNOWFALL FOR THE SEASON (2023-2024)…….0.3 DEPARTURE……-9.8

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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 The low since midnight is 16F, 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 22
HIGH 63 IN 2013
LOW -5 IN 1921
PRECIP 1.52 INS. IN 1975
SNOWFALL 8.8 INS. IN 1975
PEAK GUST 62 MPH WNW IN 1998

RECORDS FOR DECEMBER 23
HIGH 62 IN 1990
LOW -1 IN 1989
PRECIP 1.53 INS. IN 1994
SNOWFALL 11.9 INS. IN 1947
PEAK GUST 74 SE IN 2022

TODAY’S REPORT PREPARED BY: Matt Douglas