Saturday, December 12, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, DECEMBER 12, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

UNSEASONABLY WARM TEMPERATURES CONTINUE
THE DECEMBER AVERAGE TEMPERATURE IS
OVER 8 DEG. ABOVE NORMAL

Scattered clouds and above average temperatures were
present for the first observation on the summit and
despite lingering clouds, the temperature has continued
to climb this afternoon and as of the 1 o’clock observation
is now 58 degrees.  Winds remain light as the sky clears
and visibility improves to 70 miles.

Today’s Observations:

7 A.M.
Weather: Scattered Altocumulus, Scattered Cirrocumulus
Temperature: 47F; Dew Point: 39F; Wind: WSW at 12 kts
Sea-level pressure: 30.06 ins. Hg, rising slightly
Visibility: 55 mi, light distant haze
6-hr Max temp: 48F
6-hr Min temp: 46F
24-hr precip: 0.00
BHO SA 1155 20 SCT 150 SCT 55 180/47/39/2612/006/
LGT DSNT HZ ALQDS 8/099 51021 10048 20046

10 A.M.
Weather: Broken Cirrus/Cirrocumulus
Temperature: 50F; Dew Point: 38F; Wind: WSW at 10 kts,
Sea-level pressure: 30.10 ins. Hg, steady then increasing
Visibility: 55 mi, light distant haze
BHO SA 1355 E140 BKN 55 193/50/38/2610/010/LGT DSNT HZ ALQDS
8/008 53013

1 P.M.
Weather: Scattered Cirrus/Cirrocumulus
Temperature: 58F; Dew Point: 37F; Wind: WSW at 7 kts,
Sea-level pressure: 30.07 ins. Hg, steady then falling
Visibility: 70 miles
6-hr max. temp: 58F
6-hr min. temp: 46F
BHO SA 1755 140 SCT 70 183/58/37/2507/007/ 8/008 56010 10058 20046

SUMMARY FOR FRIDAY, DECEMBER 11, 2015

TEMPERATURE (DEGREES F)
MAX…..56   NORMAL…..41
MIN…..44   NORMAL…..25
MEAN….50   NORMAL…..33

DEPARTURE FROM 30-YEAR NORMAL…………………+17
TOTAL DEPARTURE FOR THE MONTH…………………+95  [+8.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..15   DEPARTURE………-17
TOTAL HEATING UNITS FOR THE MONTH………….238   DEPARTURE………-95
TOTAL HEATING UNITS FOR THE SEASON………..1240   DEPARTURE……..-355
TOTAL HEATING UNITS LAST SEASON TO DATE……1483   DIFFERENCE…….-243

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….28  SSW  AT 1:57 P.M.
ASOS……………………27  SSW  AT 1:58 P.M.
DAVIS…………………..27  SSW  AT 1:59 P.M. RMY 28
FASTEST MILE FOR YESTERDAY…………………20  SSW  AT 1:59 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………20  SSW  AT 2:00 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..18  SW   AT 1:59 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..11.8 SSW
ASOS…………………..12.3
DAVIS………………….11.0 SSW [210 Deg.] * Last of several occurrences

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………..0.38  DEPARTURE……-1.43
ASOS……………0.37
TOTAL PRECIPITATION FOR THE YEAR………..39.79  DEPARTURE…..-10.55
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…………….0.0  DEPARTURE……-3.6
TOTAL SNOWFALL FOR THE SEASON………….TRACE  DEPARTURE……-6.2

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY 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

12/1  42/30/36/-1/…./0.0/000/00           19 NNE RMY 19
12/2  53/37/45/+9/…./0.0/000/00           25 SSE RMY 25
12/3  53/37/45/+9/…./0.0/…/..           43 WNW RMY 42
12/4  47/32/40/+5/0.00/0.0/…/..           32 NW  RMY 32
12/5  50/33/42/+7/0.00/0.0/…/..           21 W   RMY N/A
12/6  57/35/46/+11/0.00/0.0/…/..          22 SW  RMY N/A
12/7  54/37/46/+12/0.00/0.0/…/..          31 NE  RMY N/A
12/8  42/35/39/+5/0.01/0.0/000/00           32 NE  RMY 31
12/9  44/34/39/+5/…./0.0/…/..           28 SSE RMY N/A
12/10 57/41/49/+16/T/0.0/…/..             29 SE  RMY N/A
12/11 56/44/50/+17/0.00/…/..              28 SSW RMY 28

12/12 low since midnight is 46F; normal low is now 25F

DAILY RECORDS FOR DECEMBER 2015

-NONE SO FAR.

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: Robert Millette