Friday, December 17, 2021

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

FRIDAY, DECEMBER 17, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0707E
SUNSET:  1613E

MILD WEATHER PERSISTS AFTER YESTERDAY’S RECORD WARMTH…

Before a cold front swung through this morning, we saw a record
tying high minimum set yesterday. 42F was the lowest the mercury
traveled which matches the reading also observed in 1982! On the
other end, the daily high came up 3 degrees short of the 61F max
cemented in 1971. As you’d expect, the average temp departure
Thursday was a beefy +18F!

A cold front punched through amidst the 7AM observation today
delivering briefly gusty winds in the 40 MPH range, yet very few
clouds and no precipitation…rather rare to see a front this dry!
Despite welcoming a new air mass, we have not had to send our
farewell to the mild temps. We are enjoying plentiful sunshine
coinciding with readings in the mid-50s.

The high so far today is 56F (set between 5a-6a), which is 16 degrees
above the normal max of 40F. The low since midnight is 50F, which
25 degrees above the normal low of 25F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Clear (few cirrus distant SE-SW)
Temperature: 52F; Dew Point: 31F; Relative Humidity: 44%
Wind: NW @ 20G34 kts
Peak Wind: 39 MPH (34 kts) NW @ 6:52 AM
Sea-level pressure: 1010.8 mb; 29.85 in. Hg: rising, then rising more rapidly
Visibility: 80 miles
6-hr Max temp: 56F
6-hr Min temp: 51F
24-hr Precip:  Trace
24-hr Snowfall: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1155 CLR 80 108/52/31/3120G34/985/ FEW CI DSNT SE-SW
PK WND 3134/52/ 8/002 53039 70000 10056 20051

10 A.M.
Weather: Clear (few cirrus distant SE-SW)
Temperature: 52F; Dew Point: 21F; Relative Humidity: 29%
Wind: WNW @ 16G24 kts
Sea-level pressure: 1014.5 mb; 29.96 in Hg; rising, then rising more slowly
Visibility: 85 miles
3-hr Precip: 0.00
3-hr Snowfall: 0.0 ins.
BHO SA 1455 CLR 85 145/52/21/3016G24/996/ FEW CI DSNT SE-SW/ 8/002 51037

1 P.M.
Weather: Clear (few cirrus distant SE-SW)
Temperature: 55F, Dew point: 20F; Relative Humidity: 25%
Wind: WNW @ 9G24 kts
Sea-level pressure: 1013.7 mb; 29.93 in Hg; falling, then falling more slowly
Visibility: 85 miles
6-hr Max temp: 56F
6-hr Min temp: 50F
6-hr Precip: 0.00 ins.
6-hr Snowfall: 0.0 ins.
Snow Depth: 0.0 ins.
BHO SA 1775 CLR 85 137/55/20/3009G24/993/ FEW CI DSNT SE-SW/ 8/002
56008 10056 20050

SUMMARY FOR THURSDAY, DECEMBER 16, 2021

TEMPERATURE (DEGREES F)
MAX…….58     NORMAL…..40
MIN…….42     NORMAL…..25
MEAN……50     NORMAL…..32

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……………+18
TOTAL DEPARTURE FOR THE MONTH………………………+79 [+4.7 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2021 THRU JUN 2022)
TOTAL HEATING UNITS FOR YESTERDAY……………15  DEPARTURE…….-18
TOTAL HEATING UNITS FOR THE MONTH…………..407  DEPARTURE…….-80
TOTAL HEATING UNITS FOR THE SEASON…………1414  DEPARTURE……-276
TOTAL HEATING UNITS LAST SEASON TO DATE…….1439  DEPARTURE…….-25

PEAK WIND GUST (MPH):
Official (1-Sec AVG)…….35 SW  @  5:37 P.M.
AEROVANE……………….37 SW  @  5:37 P.M.
VECTOR #2 (Instantaneous)..38     @  5:36 P.M.
DAVIS #2 ………………42 S   @ 12:39 A.M.
RMY #2 (Instantaneous)…..38 SW  @  2:55 A.M.
ASOS………..OUT OF SERVICE D/T RENOVATIONS
VECTOR #1……OUT OF SERVICE D/T RENOVATIONS
DAVIS #1…….OUT OF SERVICE D/T RENOVATIONS
RMY #1………OUT OF SERVICE D/T RENOVATIONS
MERLIN………OUT OF SERVICE D/T RENOVATIONS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………29 SW  @  5:35 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..28     @  5:36 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………29 S   @ 12:13 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..29 SW  @  5:37 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE…….OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE…OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE..OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE RMY #1 AVERAGE…..OUT OF SERVICE D/T RENOVATIONS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……18.5 SSW  [445 total miles] VECTOR #2…………….19.0
DAVIS #2……………..18.7 SW
RMY #2……………….19.2 SW
RMY #1…………..OUT OF SERVICE D/T RENOVATIONS
ASOS…………….OUT OF SERVICE D/T RENOVATIONS
VECTOR #1………..OUT OF SERVICE D/T RENOVATIONS
DAVIS #1…………OUT OF SERVICE D/T RENOVATIONS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……TRACE  DEPARTURE…..-0.18
TOTAL PRECIPITATION FOR THE MONTH………….1.04  DEPARTURE…..-1.82
TOTAL PRECIPITATION FOR THE YEAR………….57.81  DEPARTURE…..+6.74

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M………….0.0  DEPARTURE……-0.4
TOTAL SNOWFALL FOR THE MONTH……………….1.2  DEPARTURE……-4.1
TOTAL SNOWFALL FOR THE SEASON (2021-2022)……2.2  DEPARTURE……-5.6

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   44/30/37/0.00/0.0/…/..          35 W   AERO 35 W   RMY 34
12/02   58/35/47/10/T/0.0/…/..          56 WNW AERO 59 WNW RMY 62 TSTM
12/03   41/28/35/-1/0.00/0.0/…/..       46 NW  AERO 44 NW  RMY 46
12/04   39/25/32/-4/0.00/0.0/…/..       25 SW  AERO 23 SW  RMY 26
12/05   45/32/39/+3/0.00/0.0/…/..       25 SE  AERO 25 SE  RMY 25
12/06   59/37/48/+13/0.34/0.0/…/..      59 WNW AERO 59 NW  RMY 60
12/07   40/29/35/0/T/0.0/…/…          47 WNW AERO 36 WNW RMY 48
12/08   34/25/30/-5/0.05/0.6/…/..       26 NNE AERO 25 NE  RMY 26
12/09   35/20/28/-6/0.05/0.6/…/..       32 NW  AERO 30 NW  RMY 33
12/10   43/27/35/+1/0.00/0.0/…/..       21 SE  AERO 20 SE  RMY 21
12/11   62/37/50/+16/0.34/0.0/…/..      57 SSW AERO 59 SSW RMY 58
12/12   58/36/47/+13/0.05/0.0/…/..      55 WNW AERO 55 WNW RMY 58
12/13   50/35/43/+10/0.00/0.0/…/..      32 WSW AERO 33 WSW RMY 33
12/14   50/33/42/+9/0.00/0.0/…/..       31 WSW AERO 30 WSW RMY 32
12/15   42/28/35/+2/T/0.0/…/..          35 SSE AERO 35 SSE RMY 36
12/16   58/42/50/+18/…/0.0/…/..       35 SW  AERO 37 SW  RMY 38

12/17 The low since midnight is 50F, the daily normal low is 24F

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 59 IN 1928
LOW -11 IN 1919
PRECIP 1.44 INS. IN 1915
SNOWFALL 7.0 INS. IN 1904
PEAK GUST 76e W IN 1978

TODAY’S REPORT PREPARED BY: Andrew Swanson