Thursday, December 8, 2016

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, DECEMBER 8, 2016

MOSTLY CLOUDY SKIES AND LIGHT WINDS

Thin radiation fog was trapped beneath a temperature inversion
this morning.  Distant fog limited visibility to 20 miles but
increased to 40 miles by early afternoon.  Skies remained mostly
cloudy all day with altostratus and cirrostratus and were overcast
at the 1:00PM ob.

Rising temperatures helped to clear the morning fog and reached a
max. of 40F by 1:00PM.  The overnight low of 33F is 7F above the
normal low; however, temperatures are expected to drop even further
with the arrival of a cold front later this evening.  Winds remained
light and out of the WSW-SW during each observation.

7 A.M.
Weather: Scattered altostratus, broken cirrostratus, inversion present
with an estimated top of 400 ft., radiation fog below inversion
Temperature: 35F; Dew Point: 32F; Wind: WSW at 5 kts,
Wind Speed: Light
Sea-level pressure: 29.93 ins. Hg, rising then falling
Visibility: 20 miles, distant fog in all directions
6-hr Max temp: 35F
6-hr Min temp: 33F
24-hr precip: 0.01 in.
BHO SA 1155 120 SCT E200 BKN 20 136/35/32/2405/993/ DSNT FG ALQDS
WND LGT INVSN PRSNT ESTMD TOP 4 HND GF BLO INVSN/ 8/018 58004
MANUAL 70001 ASOS 70002 10035 20033

10 A.M.
Weather: Scattered altostratus, broken cirrostratus
Temperature: 38F; Dew Point: 34F; Wind: SW at 6 kts,
Wind Speed: Light
Sea-level pressure: 29.91 ins. Hg, falling, then more quickly
Visibility: 20 miles
BHO SA 1455 120 SCT E200 BKN 20 129/38/34/2306/991/ DSNT FG ALQDS
WND LGT/ 8/018 58007

1 P.M.
Weather: Broken altostratus, overcast cirrostratus
Temperature: 40F; Dew Point: 30F; Wind: WSW at 6 kts,
Wind Speed: Light
Sea-level pressure: 29.80 ins. Hg, falling, then more quickly
Visibility: 40 miles
6-hr Max temp: 40F
6-hr Min temp: 34F
BHO SA 1755 E89 BKN 200 OVC 40 091/40/30/2406/980/ WND LGT/
8/018 56038 10040 20034

SUMMARY FOR WEDNESDAY, DECEMBER 7, 2016

TEMPERATURE (DEGREES F)
MAX…..39   NORMAL…..42
MIN…..34   NORMAL…..27
MEAN….37   NORMAL…..34

DEPARTURE FROM 30-YEAR NORMAL……………………+3
TOTAL DEPARTURE FOR THE MONTH…………………..+16 [+2.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..28   DEPARTURE……….-3
TOTAL HEATING UNITS FOR THE MONTH………….191   DEPARTURE………-16
TOTAL HEATING UNITS FOR THE SEASON………..1121   DEPARTURE……..-248
TOTAL HEATING UNITS LAST SEASON TO DATE……1157   DIFFERENCE……..+64

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….21 E   AT 2:22 A.M.
ASOS……………………21 E   AT 2:22 A.M.
DAVIS…………………..19 E   AT 2:22 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………14 E   AT 2:22 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………15 E   AT 2:23 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..14 ENE AT 3:31 A.M.
AVERAGE WIND SPEED AND DIRECTION…………..6.6 SW
ASOS…………………..6.8
DAVIS………………….6.0 W [260 Deg.] *last of multiple occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.01  DEPARTURE……-0.16
ASOS…………..0.02
TOTAL PRECIPITATION FOR THE MONTH……….0.43  DEPARTURE……-0.72
ASOS…………..0.49
TOTAL PRECIPITATION FOR THE YEAR……….37.40  DEPARTURE…..-12.28
ASOS………….37.92

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE…….-0.3
TOTAL SNOWFALL FOR THE MONTH…………….0.4  DEPARTURE…….-1.3
TOTAL SNOWFALL FOR THE SEASON……………0.4  DEPARTURE…….-3.9

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  Low temp since midnight is 33F; normal low is now 26F

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

RECORDS FOR DECEMBER 8
HIGH 62 IN 1966
LOW -4 IN 1906
PRECIP 1.54 INS. IN 1969
SNOWFALL 2.5 INS. IN 2001
PEAK GUST 78e W IN 1979

RECORDS FOR DECEMBER 9
HIGH 68 IN 1966
LOW -14 IN 1902
PRECIP 3.23 INS. IN 2014
SNOWFALL 10.8 INS. IN 2005
PEAK GUST 66 SE IN 1973

TODAY’S REPORT PREPARED BY: Cecilia Borries-Strigle