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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, DECEMBER 12, 2016  

STORM BRINGS 0.41 IN. OF PRECIP. INCLUDING 1.3 IN. OF SNOW,
PRESSURE CONTINUES TO FALL AS SYSTEM MOVES EAST

Light snow began before midnight last night and turned to light
rain before 6:00AM this morning.  Snowfall totaled 1.3 inches
making our season total now 1.7 inches.  Total precip. is 0.41
inches as of 1:00PM this afternoon.

Thick fog limited visibility to 1/8 mile at the beginning of the
day but cleared enough for 30 miles of visibility in all directions
at the 1:00PM ob.  Winds had shifted to a southwesterly direction.
Temperatures returned to more seasonal temperatures after a few days
of cold conditions.  The overnight low was 27F occurring just after
midnight, and the max. at 1:00PM was 41F.


7 A.M.
Weather: Light rain, thick fog
Temperature: 35F; Dew Point: 35F; Wind: SE at 16G24 kts
Sea-level pressure: 29.89 ins. Hg, falling, then more slowly
Visibility: 1/8 mile
6-hr Max temp: 35F
6-hr Min temp: 27F
24-hr precip: 0.26 in.
24-hr snowfall: 1.3 in.
BHO SA 1155 W3 X 1/8R-F 121/35/35/1416G24/989/ NEW SNW PST 24 HRS 
1.3 INS/ 8//// 4/001 56062 MANUAL 70026 ASOS 70025 10035 20027

10 A.M.
Weather: Light rain, fog, sky partly obscured in fog, overcast stratus,
partial undercast SE-NNW
Temperature: 38F; Dew Point: 37F; Wind: SSW at 14 kts
Sea-level pressure: 29.78 ins. Hg, falling, then more slowly
Visibility: 5 miles, except 1/8 miles NNW-SE
3-hr precip: 0.15 in.
BHO SA 1455 -X E59 OVC 5R-F 084/38/37/2114/978/ F4 VSBY NNW-SE 1/8
PARTIAL UNDERCAST SE-NNW/ 8/6// 56031 MANUAL 6015/ ASOS 60018 

1 P.M.
Weather: Scattered cumulus fractus, scattered altostratus, 
overcast cirrostratus
Temperature: 41F; Dew Point: 38F; Wind: WSW at 11G20 kts
Sea-level pressure: 29.73 ins. Hg, falling, then more slowly
Visibility: 30 miles
6-hr Max temp: 41F
6-hr Min temp: 35F
6-hr precip: 0.15 in.
BHO SA 1755 11 SCT 140 SCT E200 OVC 30 067/41/38/2511G20/973/
8/718 55017 MANUAL 6015/ ASOS 60019 10041 20035


SUMMARY FOR SUNDAY, DECEMBER 11, 2016
 
TEMPERATURE (DEGREES F)
MAX.....33   NORMAL.....41
MIN.....16   NORMAL.....25
MEAN....25   NORMAL.....33

DEPARTURE FROM 30-YEAR NORMAL........................-8
TOTAL DEPARTURE FOR THE MONTH........................-8 [-0.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............40   DEPARTURE..........+8
TOTAL HEATING UNITS FOR THE MONTH.............341   DEPARTURE..........+8
TOTAL HEATING UNITS FOR THE SEASON...........1371   DEPARTURE........-224
TOTAL HEATING UNITS LAST SEASON TO DATE......1240   DIFFERENCE.......+131

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................17 SSW AT  1:45 P.M.
                   ASOS........................17 SSW AT  1:44 P.M.
                   DAVIS.......................16 SW  AT 11:14 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY.....................11 S   AT  4:51 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................13 S   AT  8:43 P.M. 
MAXIMUM 2-MINUTE DAVIS AVERAGE.................12 S   AT  1:45 P.M.
AVERAGE WIND SPEED AND DIRECTION..............6.8 SW
                   ASOS.......................7.1
                   DAVIS......................6.4 SSW [200 Deg.]


PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.26  DEPARTURE......+0.10
                         ASOS..............0.25
TOTAL PRECIPITATION FOR THE MONTH..........0.69  DEPARTURE......-1.12
                         ASOS..............0.74
TOTAL PRECIPITATION FOR THE YEAR..........37.66  DEPARTURE.....-12.68
                         ASOS.............38.17

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........1.3  DEPARTURE.......+0.9
TOTAL SNOWFALL FOR THE MONTH................1.7  DEPARTURE.......-1.9
TOTAL SNOWFALL FOR THE SEASON...............1.7  DEPARTURE.......-4.5


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/.../..           37 WNW AERO 39 WNW RMY 40
12/4  39/27/33/-2/0.00/0.0/.../..           25 NW  AERO 25 NW  RMY N/A
12/5  36/27/32/-3/0.13/0.4/.../..           26 W   AERO 25 W   RMY 29
12/6  42/30/36/+1/0.00/0.0/.../..           22 W   AERO 21 W   RMY N/A
12/7  39/34/37/+3/0.10/0.0/.../..           21 E   AERO 21 E   RMY N/A
12/8  40/29/35/+1/0.00/0.0/.../..           30 W   AERO 31 W   RMY 33
12/9  35/21/28/-6/0.00/0.0/.../..           35 W   AERO 36 WNW RMY 34
12/10 27/17/22/-11/0.00/0.0/.../..          26 WNW AERO 27 WNW RMY 29 
12/11 33/16/25/-8/..../.../.../..           17 SSW AERO 15 SW  RMY N/A

12/12 Low temp since midnight is 27F; normal low is now 25F


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

RECORDS FOR DECEMBER 12
HIGH 67 IN 1979
LOW -3 IN 1988
PRECIP 3.94 INS. IN 1992
SNOWFALL 20.3 INS. IN 1960
PEAK GUST 75 MPH SSE IN 2008

RECORDS FOR DECEMBER 13
HIGH 60 IN 1984
LOW 0 IN 1893
PRECIP 1.45 INS. IN 1983
SNOWFALL 9.2 INS. IN 2007
PEAK GUST 81e WNW IN 1976

TODAY'S REPORT PREPARED BY: Cecilia Borries-Strigle