Thursday, December 31, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, DECEMBER 31, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

FREEZING FOG WEDNESDAY WARMS TO THICK FOG THIS MORNING
AFTER OVERNIGHT RAIN SHOWERS, SUNSHINE BY MID MORNING TODAY

Yesterday’s mean temperature of 29F (+2) continued a streak of
warmer than normal temperatures, which now stands at 29
consecutive days. The last day of the year has so far remained
above the freezing mark, and will likely close out the month
and year above normal as well. Stay tuned for monthly and
annual statistics that will likely confirm this December as
the warmest on record.

Overnight, rain showers brought 0.16 inches of new precipitation,
further reducing this month’s deficit to 0.48 inches below normal.
Thick fog reduced visibility to 1/8 of a mile this morning
and dissipated by 9:00 AM EST. By the 1:00 PM EST skies were
mostly cloudy with broken stratocumulus above. Visibility had
improved to 65-75 miles in all directions with some thin fog
still visible over the mountains to the WSW-NW. The maximum
temperature recorded so far was 44F, some 9 degrees above
today’s daily normal maximum temperature.

BHO Latest First Measurable Snowfall, (1885-2015)

1) January  13, 2000  (7.0 inches)
2) January   1, 1954  (0.8 inches)
3) December 29, 1941  (0.4 inches)
December 29, 2015  (1.3 inches)
5) December 22, 1998  (0.6 inches)
6) December 16, 1973  (0.4 inches)
7) December 15, 1891  (0.3 inches)

BHO Largest December Daily Temperature Departure, deg F (1885-2015):

1) +35 on 29 Dec 1984 (72/51/62)
2) +30 on 25 Dec 2015 (64/52/58)
3) +29 on 23 Dec 1990 (62/53/58)
+29 on 24 Dec 2015 (67/48/58)
5) +27 on 31 Dec 1965 (62/45/54)
+27 on 22 Dec 1990 (58/53/56)
7) +26 on 27 Dec 1949 (57/51/54)
+26 on 9 Dec 1966 (68/52/60)
+26 on 6 Dec 2001 (70/52/61)

Today’s Observations:

7 A.M.
Weather: Thick fog
Temperature: 34F; Dew Point: 34F; Wind: NNW @ 10 kts
Sea-level pressure: 30.01 ins. Hg, falling, then rising but lower still
Visibility: 1/8 of a mile, thick fog
6-hr Max temp: 38F
6-hr Min temp: 32F
24-hr precip: 0.16 ins.
24-hr snowfall: Trace
BHO SA 1155 W2 X 1/8F 163/34/34/3310/001/ NEW SNW PST 24 HRS TRACE/
8//// 55001 ASOS 60007 70017 MANUAL 70016 10038 20032

10 A.M.
Weather: Clear, few stratocumulus/cumulus in all directions,
few altocumulus distant E-SSw, few cirrostratus distant E-SW,
thin fog in all directions
Temperature: 38F; Dew Point: 37F; Wind: WNW @ 8 kts,
Sea-level pressure: 30.02 ins. Hg, rising, then more slowly
Visibility: 30 miles, except 8 miles ESE-SSW, thin fog
BHO SA 1455 CLR 30 166/38/37/3008/002/ VSBY ESE-SSW 8 MI
FEW SC/CU ALQDS FEW AC DSNT E-SSW FEW CS DSNT E-SW
THN FG ALQDS/ 8/538 51003

1 P.M.
Weather: Broken stratocumulus
Temperature: 42F; Dew Point: 37F; Wind: WNW @ 12 kts
Sea-level pressure: 29.96 ins. Hg, rising, then falling and lower
Visibility: 75 miles, except 65 miles WSW-NW, thin fog WSW-NW
6-hr Max temp: 44F
6-hr Min temp: 34F
6-hr precip: 0.00
6-hr snowfall: 0.0
BHO SA 1755 E16 BKN 75 147/42/37/3012/996/
VSBY WSW-NW 65 MI THN FG WSW-NW/ 8/500 58019 10044 20034

SUMMARY FOR WEDNESDAY, DECEMBER 30, 2015

TEMPERATURE (DEGREES F)
MAX…..34   NORMAL…..35
MIN…..23   NORMAL…..19
MEAN….29   NORMAL…..27

DEPARTURE FROM 30-YEAR NORMAL………………….+2
TOTAL DEPARTURE FOR THE MONTH………………..+377  [+12.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..36   DEPARTURE……….-2
TOTAL HEATING UNITS FOR THE MONTH………….626   DEPARTURE……..-379
TOTAL HEATING UNITS FOR THE SEASON………..1628   DEPARTURE……..-639
TOTAL HEATING UNITS LAST SEASON TO DATE……2016   DIFFERENCE…….-388

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….17  SSE AT 11:55 P.M.
ASOS……………………17  NNW AT  6:08 A.M.
DAVIS…………………..15  SE  AT 10:37 P.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………13  SSE AT 11:56 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………15  E   AT  8:05 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..13  SE  AT 10:39 P.M.
AVERAGE WIND SPEED AND DIRECTION……………3.4 N
ASOS……………………6.9
DAVIS…………………..3.0 ENE [060 Deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…..0.16  DEPARTURE……+0.02
ASOS……………0.17
TOTAL PRECIPITATION FOR THE MONTH………..4.27  DEPARTURE……-0.48
ASOS……………4.34
TOTAL PRECIPITATION FOR THE YEAR………..43.69  DEPARTURE……-9.60
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……..TRACE  DEPARTURE…….-0.5
TOTAL SNOWFALL FOR THE MONTH…………….1.3  DEPARTURE……-11.5
TOTAL SNOWFALL FOR THE SEASON……………1.3  DEPARTURE……-14.1

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/-1/0.16/0.0/000/00           19 NNE RMY 19
12/2  53/37/45/+9/0.20/0.0/000/00           25 SSE RMY 25
12/3  53/37/45/+9/0.01/0.0/162/29           43 WNW RMY 42
12/4  47/32/40/+5/0.00/0.0/444/80           32 NW  RMY 32
12/5  50/33/42/+7/0.00/0.0/548/99           21 W   RMY N/A
12/6  57/35/46/+11/0.00/0.0/531/96          22 SW  RMY N/A
12/7  54/37/46/+12/0.00/0.0/353/64          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/…./0.0/044/08           28 SSE RMY N/A
12/10 57/41/49/+16/T/0.0/209/38             29 SE  RMY N/A
12/11 56/44/50/+17/0.00/0.0/049/09          28 SSW RMY 28
12/12 59/46/53/+20/0.00/0.0/367/67          23 W   RMY N/A
12/13 54/44/49/+17/0.00/0.0/000/00          18 ESE RMY 19
12/14 60/43/52/+20/…./0.0/000/00          32 S   RMY N/A
12/15 61/45/53/+21/…./0.0/371/68          48 W   RMY 51
12/16 45/34/40/+9/0.00/0.0/415/76           25 N   RMY N/A
12/17 53/36/45/+14/…./0.0/000/00          29 SE  RMY 28
12/18 50/35/43/+12/…./0.0/000/00          29 NW  RMY 30
12/19 38/30/34/+4/0.00/0.0/…/..           39 W   RMY 40
12/20 40/28/34/+4/0.00/0.0/…/..           24 W   RMY N/A
12/21 51/31/41/+11/T/0.0/…/..             38 SSW RMY 42
12/22 57/49/53/+24/0.28/0.0/000/00          35 SW  RMY 35
12/23 56/47/52/+23/…./0.0/…/..          30 E   RMY 27
12/24 67/48/58/+29/…./0.0/…/..          37 SSW RMY 39
12/25 64/52/58/+30/…./0.0/…/..          23 N   RMY N/A
12/26 53/40/47/+19/…./0.0/…/..          26 NNW RMY N/A
12/27 52/35/44/+16/…./0.0/000/00          36 NW  RMY 33
12/28 35/27/31/+3/T/T/…/..                33 NW  RMY 33
12/29 38/23/31/+4/…./1.3/000/00           35 ENE RMY 35
12/30 34/23/29/+2/…./T/000/00             17 SSE RMY N/A

12/31 low since midnight is 32F; normal low is now 19F

DAILY RECORDS FOR DECEMBER 2015

**12/13/2015- NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 44F,
BREAKS PREVIOUS RECORD OF 43F SET IN 1919, TIED 1983
**12/24/2015- NEW DAILY RECORD MAXIMUM TEMPERATURE OF 67F,
BREAKS PREVIOUS RECORD OF 61F SET IN 2014
**12/24/2015- NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 48F,
BREAKS PREVIOUS RECORD OF 46F SET IN 1900
**12/25/2015- NEW DAILY RECORD MAXIMUM TEMPERATURE OF 64F,
BREAKS PREVIOUS RECORD OF 62F SET IN 1889
**12/25/2015- NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 52F,
BREAKS PREVIOUS RECORD OF 46F SET IN 1964

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

RECORDS FOR DECEMBER 31
HIGH 62 IN 1965
LOW -12 IN 1917
PRECIP 0.96 INS. IN 1906
SNOWFALL 7.5 INS. IN 2008
PEAK GUST 78 MPH NW IN 1990

RECORDS FOR JANUARY 1
HIGH 58F IN 1966
LOW -6F IN 1918
PRECIP 1.45 INS. IN 1982
SNOWFALL 7.2 INS. IN 1938
PEAK GUST 90e MPH S IN 1945

TODAY’S REPORT PREPARED BY: Brian Fitzgerald