Sunday, December 18, 2016

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, DECEMBER 18, 2016

Unseasonably warm temperatures started the day at the first
observation along with gusty winds and a thick fog on the summit.
The Fog gave way by the 10 o’clock observation but temperatures
and winds continued to climb.  By the 1 o’clock observation,
temperatures had reached 54 degrees, just 5 degrees below the
record set back in 1928. Winds as of this observation are average
26 miles per hour for the day.

7 A.M.
Weather: Thick Fog
Temperature: 49F; Dew Point: 49F; Wind: S at 24 kts gusts to 33 kts
Sea-level pressure: 29.69 ins. Hg, falling, then more rapidly
Visibility: 1/8 miles
6-hr Max temp: 49F
6-hr Min temp: 37F
24-hr precip: 0.51 in.
BHO SA 1155 W3 X 1/8F 056/49/49/1924G33/969/ 8//// 58035
MANUAL 70051 ASOS 70052 10037 20049

10 A.M.
Weather: Overcast Stratus
Temperature: 54F; Dew Point: 53F; Wind: SW at 25 kts, gust N/A
Sea-level pressure: 29.72 ins. Hg, falling then rising
Visibility: 30 miles
BHO SA 1455 E5 OVC 30 064/54/53/2225/972/ 8/6// 53008

1 P.M.
Weather: Overcast Stratus
Temperature: 54F; Dew Point: 52F; Wind: SW at 21 kts, gusts to 35
Sea-level pressure: 29.71 ins. Hg, falling, then rising but lower
Visibility: 25 mile
6-hr Max temp: 54F
6-hr Min temp: 49F
6-hr precip: Trace
BHO SA 1755 E14 OVC 25 061/54/52/2221G35/971/ HAZE/ 8/6//
55003 MANUAL 6000/ ASOS 60004 10054 20049

SUMMARY FOR SATURDAY, DECEMBER 17, 2016

TEMPERATURE (DEGREES F)
MAX…..36   NORMAL…..38
MIN…..18   NORMAL…..23
MEAN….27   NORMAL…..31

DEPARTURE FROM 30-YEAR NORMAL…………………..-4
TOTAL DEPARTURE FOR THE MONTH…………………..-38 [-2.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..38   DEPARTURE………+3
TOTAL HEATING UNITS FOR THE MONTH………….570   DEPARTURE………+36
TOTAL HEATING UNITS FOR THE SEASON………..1600   DEPARTURE……..-196
TOTAL HEATING UNITS LAST SEASON TO DATE……1338   DIFFERENCE…….+262

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….28 SSW AT 11:58 P.M.
ASOS……………………29 SSW AT 11:59 P.M.
DAVIS…………………..28 SSE AT 11:58 P.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………23 SSW AT 11:59 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………23 S   AT 11:59 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..22 SSE AT 11:59 P.M.
AVERAGE WIND SPEED AND DIRECTION………….10.6 SE
ASOS………………….11.0
DAVIS………………….9.8 SE [141 Deg.] *last of multiple occurances

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.51  DEPARTURE……+0.35
ASOS…………..0.52
TOTAL PRECIPITATION FOR THE MONTH……….1.49  DEPARTURE……-1.29
ASOS…………..1.59
TOTAL PRECIPITATION FOR THE YEAR……….38.45  DEPARTURE…..-12.85
ASOS………….39.02

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….2.6  DEPARTURE…….+2.2
TOTAL SNOWFALL FOR THE MONTH…………….6.0  DEPARTURE…….-0.2
TOTAL SNOWFALL FOR THE SEASON……………6.0  DEPARTURE…….-2.8

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

12/1  55/39/47/+10/0.20/0.0/385/69          36 W   AERO 37 W   RMY 36
12/2  48/34/41/+5/0.00/0.0/535/96           32 W   AERO 32 W   RMY N/A
13/3  44/31/38/+2/0.00/0.0/445/80           37 WNW AERO 39 WNW RMY 40
12/4  39/27/33/-2/0.00/0.0/355/64           25 NW  AERO 25 NW  RMY N/A
12/5  36/27/32/-3/0.13/0.4/000/00           26 W   AERO 25 W   RMY 29
12/6  42/30/36/+1/0.00/0.0/392/71           22 W   AERO 21 W   RMY N/A
12/7  39/34/37/+3/0.10/0.0/000/00           21 E   AERO 21 E   RMY N/A
12/8  40/29/35/+1/0.00/0.0/033/06           30 W   AERO 31 W   RMY 33
12/9  35/21/28/-6/0.00/0.0/549/100          35 W   AERO 36 WNW RMY 34
12/10 27/17/22/-11/0.00/0.0/544/99          26 WNW AERO 27 WNW RMY 29
12/11 33/16/25/-8/0.06/0.4/411/75           17 SSW AERO 15 SW  RMY N/A
12/12 41/27/34/+1/0.35/0.9/038/07           29 ESE AERO 29 SE  RMY 30
12/13 41/30/36/+4/0.00/0.0/…/..           25 WSW AERO 25 W   RMY 27
12/14 40/26/33/+1/0.00/0.0/…/..           30 WNW AERO 31 WNW RMY N/A
12/15 29/13/21/-11/T/T/…/..               50 W   AERO 62 W   RMY 56
12/16 18/01/10/-21/0.00/0.0/…/..          39 WNW AERO 51 WNW RMY N/A
12/17 36/18/27/-4/0.51/2.6/…/..           25 SSW AERO 28 SSW RMY N/A

12/18 Low temp since midnight is 37F; normal low is now 23F

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

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

RECORDS FOR DECEMBER 19
HIGH 59 IN 1899
LOW -1 IN 1919
PRECIP 2.06 INS. IN 1986
SNOWFALL 14.1 INS. IN 1945
PEAK GUST 68 NE IN 1986

TODAY’S REPORT PREPARED BY: Robert Millette