Friday, December 15, 2017
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, DECEMBER 15, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME
BELOW SEASONABLE TEMPERATURES CONTINUE…
Overnight was observed the lowest minimum
temperature so far this season at 12F. This
is 12 degrees below the daily normal of 24F.
Yesterday was also well below seasonable with
a high maximum temperature of 27F. This is
13 degrees below the daily normal of 40F. So
far today we have had a high of 23F. Wind
today came from the south and was light for
most of the day. Pressure started dropping
late in the morning, and the sky cover
increased all morning until we had overcast
cirrostratus by 1:00 P.M.
Today’s Observations:
7 A.M.
Weather: Scattered cirrostratus
Temperature: 13F; Dew Point: 5F; Wind: SSW at 6 kts,
Wind: Light
Sea-level pressure: 30.07 ins. Hg, rising, then more quickly
Visibility: 60 miles
6-hr Max temp: 14F
6-hr Min temp: 12F
24-hr precip: Trace
24-hr snowfall: Trace
Snow cover: 1 in.
BHO SA 1155 250 SCT 60 184/13/05/2106/007/ NEW SNW PST
24 HRS TRACE WND LGT/ 8/006 4/001 53010 10014 20012
10 A.M.
Weather: Broken cirrostratus, smoke layer along
horizon W-ENE
Temperature: 19F; Dew Point: 9F; Wind: S at 4 kts,
Wind: Light
Sea-level pressure: 30.11 ins. Hg, rising, then more quickly
Visibility: 70 miles
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins.
BHO SA 1455 E200 BKN 70 195/19/09/1904/011/ K LYR ALG
HRZN W-ENE WND LGT/ 8/006 53011
1 P.M.
Weather: Scattered altocumulus, overcast cirrostratus
thin smoke layer along horizon W-NNE, sun dimly visible
Temperature: 23F; Dew Point: 11F; Wind: SSW at 5 kts,
Wind: Light
Sea-level pressure: 30.02 ins. Hg, falling, then more quickly
Visibility: 70 miles
6-hr Max temp: 23F
6-hr Min temp: 13F
6-hr precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
Snow cover: 1 in.
BHO SA 1755 120 SCT E200 OVC 70 167/23/11/2005/002/ THN K LYR
ALG HRZN W-NNE SUN DMLY VSBL WND LGT/ 8/086 4/001 56028
10023 20013
SUMMARY FOR THURSDAY, DECEMBER 14, 2017
TEMPERATURE (DEGREES F)
MAX…..27 NORMAL…..40
MIN…..14 NORMAL…..24
MEAN….21 NORMAL…..32
DEPARTURE FROM 30-YEAR NORMAL……………………..-11
TOTAL DEPARTURE FOR THE MONTH……………………..+14 [+0.8 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….44 DEPARTURE………+11
TOTAL HEATING UNITS FOR THE MONTH…………471 DEPARTURE………-15
TOTAL HEATING UNITS FOR THE SEASON……….1386 DEPARTURE……..-307
TOTAL HEATING UNITS LAST SEASON TO DATE…..1463 DIFFERENCE……..-77
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….35 WSW AT 12:13 A.M.
AERO……………………33 W AT 6:12 P.M.
ASOS……………………33 WSW AT 12:14 A.M.
DAVIS…………………..32 WSW AT 12:13 A.M. RMY 34
FASTEST MILE FOR YESTERDAY…………………24 WNW AT 2:06 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………24 W AT 7:39 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..24 W AT 6:12 P.M.
AVERAGE WIND SPEED AND DIRECTION………….13.3 W
ASOS………………….12.9
DAVIS…………………12.8 WNW [286 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……-0.76
ASOS…………..1.63
TOTAL PRECIPITATION FOR THE YEAR……….51.38 DEPARTURE……+0.55
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…….-0.4
TOTAL SNOWFALL FOR THE MONTH…………….5.6 DEPARTURE…….+0.7
TOTAL SNOWFALL FOR THE SEASON……………5.6 DEPARTURE……-0.55
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/+3/0.00/522/98 25 WSW AERO 24 WSW RMY 25
12/08 38/28/33/-1/0.00/…/.. 21 W AERO 18 W RMY 20
12/09 34/28/31/-3./…./…/.. 23 NNW AERO 23 NNW RMY 23
12/10 35/27/31/-2/…./…/.. 30 W AERO 30 W RMY 27
12/11 38/29/34/+1/0.00/…/.. 23 W AERO 21 W RMY 22
12/12 43/31/37/+4/0.06/…/.. 35 W AERO 31 W RMY N/A
12/13 31/18/25/-7/0.00/…/.. 44 W AERO 44 W RMY 44
12/14 27/14/21/-11/T/…/.. 35 WSW AERO 33 W RMY 34
12/15 Low temp since midnight is 12F; normal low is now 24F
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
RECORDS FOR DECEMBER 15
HIGH 64 IN 1975
LOW 4 IN 1900, 1905, 1933
PRECIP 1.80 INS. IN 1981
SNOW 7.5 INS. IN 1951
PEAK GUST 65 MPH NW IN 1991
RECORDS FOR DECEMBER 16
HIGH 61 IN 1971
LOW -2 IN 1930
PRECIP 1.67 INS. IN 1960
SNOW 8.5 INS. IN 2007
WIND 73 MPH SSE IN 1982
TODAY’S REPORT PREPARED BY: Kaitlin Geagan
