Friday, December 22, 2017

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, DECEMBER 22, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME

COOL TEMPERATURES AND LIGHT WINDS

A maximum temperature of 32F was reached yesterday. With a low
of 23F, the average temperature was 2F below normal. This morning,
a low of 21F was recorded, and a maximum of 27F was reached by the
1:00 P.M. EST observation. The air became slightly more humid into
the afternoon, with the dew point rising from 11F at 7:00 A.M. to
23F at 1:00 P.M. There was a layer of overcast stratus in the area
all day, and precipitation is expected later this afternoon.

Yesterday and into this morning, winds were light out of the
northwest. The peak gust yesterday was 26 MPH out of the northwest
at 9:06 A.M., but the winds calmed down that afternoon. Around
7:00 A.M. this morning, winds began to shift towards the northeast.
Winds were light early, but they began to pick up late this morning.
So far, the peak gust has been 14 MPH out of the northeast,
occurring at 11:48 A.M.

Today’s Observations:

7 A.M.
Weather: Overcast stratus
Temperature: 22F; Dew Point: 11F; Wind: NNW at 4 kts,
Wind speed: Light
Sea-level pressure: 30.39 ins. Hg, rising unsteadily
Visibility: 30 miles, except for 60 miles E-S
6-hr Max temp: 24F
6-hr Min temp: 21F
24-hr precip: 0.00 ins.
24-hr snowfall: 0.0 ins.
Snow cover: 0 ins.
BHO SA 1155 E072 OVC 30 291/22/11/3304/039/ VSBY E-S 60 WND LGT/
8/6// 52015 10024 20021

10 A.M.
Weather: Overcast stratus, few stratocumulus NNE-ESE
Temperature: 24F; Dew Point: 10F; Wind: Estimated NE at 2 kts,
Wind speed: Light
Sea-level pressure: 30.40 ins. Hg, steady, then rising
Visibility: 50 miles
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins.
BHO SA 1455 E72 OVC 50 294/24/10/E0502/040/ FEW SC NNE-ESE WND LGT/
8/6// 53002

1 P.M.
Weather: Overcast stratus
Temperature: 26F; Dew Point: 23F; Wind: NE at 7 kts
Sea-level pressure: 30.32 ins. Hg, falling, then more quickly
Visibility: 30 miles, distant fog in all directions
6-hr Max temp: 27F
6-hr Min temp: 22F
6-hr precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
Snow cover: 0 ins.
BHO SA 1755 E52 OVC 30 266/26/23/0507/032/ DSNT FG ALQDS/
8/6// 58028 10027 20022

SUMMARY FOR THURSDAY, DECEMBER 21, 2017

TEMPERATURE (DEGREES F)
MAX…..32   NORMAL…..37
MIN…..23   NORMAL…..22
MEAN….28   NORMAL…..30

DEPARTURE FROM 30-YEAR NORMAL………………………-2
TOTAL DEPARTURE FOR THE MONTH………………………-4 [-0.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….37  DEPARTURE……….+2
TOTAL HEATING UNITS FOR THE MONTH…………676  DEPARTURE……….+2
TOTAL HEATING UNITS FOR THE SEASON……….1645  DEPARTURE……..-290
TOTAL HEATING UNITS LAST SEASON TO DATE…..1737  DIFFERENCE……..-92

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….26 NW  AT 9:06 A.M.
AERO……………………24 NW  AT 9:03 A.M.
ASOS……………………27 WNW AT 9:00 A.M.
DAVIS…………………..25 NW  AT 9:06 A.M. RMY 27
FASTEST MILE FOR YESTERDAY…………………20 NW  AT 9:03 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………20 NW  AT 9:04 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..19 NW  AT 9:05 A.M.
AVERAGE WIND SPEED AND DIRECTION…….. …..8.9 NW
ASOS……………….. ..9.1
DAVIS………………. ..8.5 NNW [330 DEG.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.16
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.54  DEPARTURE……-1.85
ASOS…………..1.63
TOTAL PRECIPITATION FOR THE YEAR……….51.38  DEPARTURE……-0.54
ASOS……………N/A **
** ASOS annual total not available due to erroneous readings

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE…….-0.5
TOTAL SNOWFALL FOR THE MONTH…………….5.7  DEPARTURE…….-2.5
TOTAL SNOWFALL FOR THE SEASON……………5.7  DEPARTURE…….-5.1

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 50/35/43/+6/0.04/262/47          28 NW  AERO 29 NW  RMY 30
12/02 42/29/36/0/0.00/033/06           20 NNW AERO 18 NNW RMY N/A
12/03 42/32/37/+1/0.00/172/31          14 N   AERO 10 N   RMY N/A
12/04 43/32/38/+3/0.00/522/94          16 E   AERO 14 E   RMY N/A
12/05 58/34/46/+11/0.18/000/00         62 S   AERO 66 S   RMY 65
12/06 56/32/44/+9/0.54/160/29          52 S   AERO 55 S   RMY N/A
12/07 44/30/37/+3/0.00/540/98          25 WSW AERO 24 WSW RMY 25
12/08 38/28/33/-1/0.00/116/21          21 W   AERO 18 W   RMY 20
12/09 34/28/31/-3./0.70/000/00         23 NNW AERO 23 NNW RMY 23
12/10 35/27/31/-2/0.02/384/70          30 W   AERO 30 W   RMY 27
12/11 38/29/34/+1/0.00/301/55          23 W   AERO 21 W   RMY 22
12/12 43/31/37/+4/0.06/000/00          35 W   AERO 31 W   RMY N/A
12/13 31/18/25/-7/0.00/312/57          44 W   AERO 44 W   RMY 44
12/14 27/14/21/-11/T/…/..            35 WSW AERO 33 W   RMY 34
12/15 24/12/18/-14/T/…/..            25 W   AERO 23 W   RMY N/A
12/16 32/17/25/-6/0.00/…/..          33 W   AERO 35 W   RMY 36
12/17 27/14/21/-10/0.00/…/..         21 NW  AERO 21 NW  RMY 20
12/18 35/20/28/-3/T/…/..             20 SSE AERO 16 SSE RMY 20
12/19 49/34/42/+12/T/…/..            36 WNW AERO 35 SW  RMY 38
12/20 42/26/34/+4/T/…/..             41 W   AERO 40 W   RMY 45
12/21 32/23/-2/0.00/…/..             26 NW  AERO 24 NW  RMY 27

12/22 Low temp since midnight is 21F; normal low is now 22F

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 1.70 INS. IN 1947
SNOWFALL 11.9 INS. IN 1947
PEAK GUST 67 SSE IN 2004

TODAY’S REPORT PREPARED BY: Lizzy Suzedell