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

WEDNESDAY, DECEMBER 22, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0711E
SUNSET:  1615E

OVERCAST WITH SOME LIGHT RAIN, BRIEFLY MILD MID MORNING....

A coastal front was playing hop-scotch with the hill for a time
this morning before finally drifting eastward. The temperature
was steadily rising through the wee hours of the morning, into
the low 40s by 4am. The front drifted back to the east briefly
between 6:30am and 7:30am when the temperature dropped from the
low 40s to the mid 30s. The front then moved back west and
temperatures rose back into the 40s, peaking at 45 degrees
between 9:00am-9:45am. It then drifted back to the east and
stayed that way through early afternoon. Temperatures dropped
rapidly on the west side of this boundary with a low of 33 degrees
occurring between 11am-12pm! So our max and min temperatures for
the day so far occurred within 2 hours of each other mid-late
this morning.

Light rain was occurring off and on starting between 4am-5am this
morning and lasting through the 1pm observation. Only 0.10" has
been measured however, all of that occurring between 11am-1pm. Only
traces where measured before that.

The wind has been all over the compass rose depending on which
side of the coastal front we were on. E to S for a time while
on the mild side, and then NW to N on the cool side. Speeds have
been mainly light most of the morning except for a brief period
of gusty winds once the boundary moved east the final time. A
peak gust of 31 mph was measured during that time. The wind is
expected to increase later this afternoon, so perhaps we'll see
a higher peak gust for the day later.

Visibility has been non-existent so far today as we've been in the
clouds. Clearing should occur later this afternoon however.

The high so far today is 45F, which is 6 degrees above the normal
max of 39F. The low since midnight is 33F, which is 10 degrees
above the normal low of 23F.

--------------------------------------------------------------

Today's Observations:

7 A.M.
Weather: Overcast stratus, light drizzle
Temperature: 40F; Dew Point: 39F; Relative Humidity: 96%
Wind: NNE @ 6 kts
Sea-level pressure: 1002.7 mb; 29.61 in. Hg: falling, then more slowly
Visibility: 1.5 miles, fog
6-hr Max temp: 42F
6-hr Min temp: 37F
24-hr Precip:  TRACE
24-hr Snowfall: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1155 E2 OVC 11/2L-F 027/40/39/0306/961/ PCPN VRY LGT R-E00B23E30
L-B45/ 8/6// 56036 6000/ 70000 10042 20037

10 A.M.
Weather: Sky obscured, vertical visibility 200 ft, very light rain
Temperature: 38F; Dew Point: 38F; Relative Humidity: 100%
Wind: NW @ 4 kts, wind light, wind shift at 9:55 A.M.
Sea-level pressure: 999.0 mb; 29.50 in Hg; falling, then more slowly
Visibility: 3/4 mile, fog
3-hr Precip: TRACE
3-hr Snowfall: 0.0 ins.
BHO SA 1455 X W2 3/4R-F 990/38/38/3104/950/ R-B15 PCPN VRY LGT
WSHFT 55 WND LGT/ 8//// 56037 6000/

1 P.M.
Weather: Sky obscured, vertical visibility 200 ft, light rain
Temperature: 36F, Dew point: 36F; Relative Humidity: 100%
Wind: NW @ 12G17kts
Sea-level pressure: 997.1 mb; 29.44 in Hg; falling, then more slowly
Visibility: 1/8 mile, fog
6-hr Max temp: 45F
6-hr Min temp: 33F
6-hr Precip:   0.10 ins.
6-hr Snowfall: 0.0 ins.
Snow Depth: 0.0 ins.
BHO SA 1755 X W2 1/8R-F 971/36/36/3212G17/944/ 8//// 56019 6010/ 10045 20033


SUMMARY FOR TUESDAY, DECEMBER 21, 2021

TEMPERATURE (DEGREES F)
MAX.......40     NORMAL.....39
MIN.......27     NORMAL.....24
MEAN......34     NORMAL.....31

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL............... +3
TOTAL DEPARTURE FOR THE MONTH...........................+92 [+4.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2021 THRU JUN 2022)
TOTAL HEATING UNITS FOR YESTERDAY...............31  DEPARTURE........-3
TOTAL HEATING UNITS FOR THE MONTH..............561  DEPARTURE.......-92
TOTAL HEATING UNITS FOR THE SEASON............1568  DEPARTURE......-289
TOTAL HEATING UNITS LAST SEASON TO DATE.......1633 DEPARTURE........-65

PEAK WIND GUST (MPH):
                     Official (1-Sec AVG).......31 SW  @  2:37 A.M.
                     AEROVANE...................32 SW  @  2:38 A.M.
                     VECTOR #2 (Instantaneous)..34     @  2:37 A.M.
                     DAVIS #2 ..................30 WSW @  3:16 A.M.
                     RMY #2 (Instantaneous).....33 SW  @  2:37 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..................22 SW  @  2:14 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE..............22     @  2:39 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE...............22 SW  @  2:39 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE.................22 SW  @  2:39 A.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.....10.2 SW  [244 total miles]
                     VECTOR #2...............11.0
                     DAVIS #2................10.8 SW
                     RMY #2..................11.0 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.............1.95  DEPARTURE.....-1.79
TOTAL PRECIPITATION FOR THE YEAR.............58.72  DEPARTURE.....+6.77

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M.............0.0  DEPARTURE......-0.5
TOTAL SNOWFALL FOR THE MONTH...................1.4  DEPARTURE......-6.2
TOTAL SNOWFALL FOR THE SEASON (2021-2022)......2.4  DEPARTURE......-7.7


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   44/30/37/0.00/0.0/263/47          35 W   AERO 35 W   RMY 34      
12/02   58/35/47/10/T/0.0/106/19          56 WNW AERO 59 WNW RMY 62 TSTM
12/03   41/28/35/-1/0.00/0.0/512/92       46 NW  AERO 44 NW  RMY 46
12/04   39/25/32/-4/0.00/0.0/233/42       25 SW  AERO 23 SW  RMY 26
12/05   45/32/39/+3/0.00/0.0/460/83       25 SE  AERO 25 SE  RMY 25
12/06   59/37/48/+13/0.34/0.0/077/14      59 WNW AERO 59 NW  RMY 60
12/07   40/29/35/0/T/0.0/436/79           47 WNW AERO 36 WNW RMY 48
12/08   34/25/30/-5/0.05/0.6/000/00       26 NNE AERO 25 NE  RMY 26
12/09   35/20/28/-6/0.05/0.6/319/58       32 NW  AERO 30 NW  RMY 33
12/10   43/27/35/+1/0.00/0.0/000/00       21 SE  AERO 20 SE  RMY 21
12/11   62/37/50/+16/0.34/0.0/000/00      57 SSW AERO 59 SSW RMY 58
12/12   58/36/47/+13/0.05/0.0/416/76      55 WNW AERO 55 WNW RMY 58
12/13   50/35/43/+10/0.00/0.0/224/41      32 WSW AERO 33 WSW RMY 33
12/14   50/33/42/+9/0.00/0.0/442/81       31 WSW AERO 30 WSW RMY 32
12/15   42/28/35/+2/T/0.0/153/28          35 SSE AERO 35 SSE RMY 36
12/16   58/42/50/+18/0.21/0.0/016/03      35 SW  AERO 37 SW  RMY 38
12/17   56/39/48/+16/0.00/0.0/518/95      43 WNW AERO 41 WNW RMY 46
12/18   39/31/35/+3/0.52/0.2/000/00       21 NNW AERO 20 NNW RMY 20
12/19   39/20/30/-2/0.39/0.0/.../..       35 NNW AERO 37 NNW RMY 36
12/20   32/15/24/-7/0.00/0.0/.../..       29 SSW AERO 30 SSW RMY 30
12/21   40/27/34/+3/0.00/0.0/.../..       31 SW  AERO 32 SW  RMY 33

12/22 The low since midnight is 33F, the daily normal low is 23F

DAILY RECORDS FOR DECEMBER 2021

12/16/21: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 42F
          TIES PREVIOUS RECORD OF 42F SET IN 1982


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 67 SSE IN 2004

TODAY'S REPORT PREPARED BY: Matt Douglas