Thursday, January 5, 2017

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, JANUARY 5, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME

WINTER FEEL RETURNS TODAY WITH COOLER TEMPS AND GUSTY WINDS

After a very warm start to the month, a more winter-like feel has returned
to the air today.  The morning low was still a relatively mild 23F, but
we’ve seen only a slow rise of the temperature to 30F through 1:00 P.M.
Winds have been gusty as well out of the west, helping to lock in this cool,
dry air.  Several gusts of around 35mph occurred during the mid-morning,
with breezy conditions continuing into the afternoon.  Plenty of sunshine
has been observed today, although high clouds have created a thin veil
over most of the sky by early afternoon.  Visibility has been excellent,
improving to 80 miles this afternoon.

Rain and snow squalls passed through the region last night.  Only a trace
of snow was recorded here with 0.03 ins. of liquid.  The squall passages
were easily discernible on our wind charts, with each one corresponding to
a sudden uptick in the wind.  A peak gust of 41mph was recorded.

It appears 2016 will go down as the 2nd warmest year on record here at the
Observatory.  A list of our ten warmest years, along with preliminary
statistics for December, are below.

BLUE HILL OBSERVATORY WARMEST ANNUAL TEMPERATURE 1885-2016 (deg F)
1) 51.7 in 2012
2) 51.2 in 2016
3) 51.0 in 2010
4) 50.9 in 1999
5) 50.8 in 1998
6) 50.6 in 2006
7) 50.5 in 1953
8) 50.4 in 2011
9) 50.3 in 1990, 1991

PRELIMINARY STATS FOR DECEMBER 2016

TEMPERATURE, Deg. F
Avg. Max. 39.5 [+0.4] Avg. Min. 25.3 [+1.7] Mean      32.4 [+1.1] 24-hour corrected mean: 32.1
Max. for month: 56F on 27th
Min. for month:  1F on 16th

HEATING DEGREE DAYS
Total heating units: 1002 [-41] Total for the season: 2032 [-273] Total for last season: 1656

PRECIPITATION, Inches
Total: 2.83 [-2.06] Greatest in 24 hrs: 0.87 in. on 29th-30th

SNOWFALL, Inches
Total: 7.8 [-5.6] Greatest in 24 hrs: 4.3 in. on 17th

WIND, mph
Avg. uncorrected wind speed: 13.4
Avg. corrected wind speed: 13.7
Prevailing wind direction: W at 19%
Peak gust and direction: 51 SW on 27th

SUNSHINE:
Campbell-Stokes card minutes: 8604 mins. of possible 16470 mins. or 52%
Astronomical total minutes: 8881 mins. of possible 16991 mins. or 52%

Today’s Observations:

7 A.M.
Weather: Clear, few stratocumulus WNW-NW and distant NNE-S, few
altocumulus SE-W
Temperature: 23F; Dew Point: 12F; Wind: W at 15G22 kts
Sea-level pressure: 29.79 ins. Hg, rising
Visibility: 55 miles
6-hr Max temp: 29F
6-hr Min temp: 23F
24-hr precip: 0.03 ins.
24-hr snowfall: Trace
BHO SA 1155 CLR 55 088/23/12/2715G22/979/ FEW SC WNW-NW AND DSNT NNE-S
FEW AC SE-W NEW SNW PST 24 HRS TRACE/ 8/530 52038 MANUAL 70003 ASOS 70003
10029 20023

10 A.M.
Weather: Scattered cirrus, few stratocumulus distant SW-N and NE-S,
dense cirrus SSE-SW, patches of cirrocumulus overhead and SW
Temperature: 27F; Dew Point: 10F; Wind: W at 19G28 kts,
Wind: Peak Wind 32 kts W at 9:30 A.M.
Sea-level pressure: 29.86 ins. Hg, rising then more slowly
Visibility: 70 miles
BHO SA 1455 250 SCT 70 112/27/10/2719G28/986/ FEW SC DSNT SW-N AND NE-S
DNS CI SSE-SW PTCHS CC OVHD AND SW PK WND 2732/30/ 8/509 51024

1 P.M.
Weather: Broken altostratus, broken cirrus, few stratocumulus distant all
quadrants except E-SSW, few altocumulus and altocumulus lenticularis
distant WSW-N, partial solar halo
Temperature: 30F; Dew Point: 11F; Wind: W at 12 kts,
Wind: Peak Wind 27 kts W at 12:10 P.M.
Sea-level pressure: 29.83 ins. Hg, rising then falling
Visibility: 80 miles
6-hr Max temp: 30F
6-hr Min temp: 23F
BHO SA 1755 E180 BKN 250 BKN 80 101/30/11/2712/983/
FEW SC DSNT ALQDS XCPT E-SSW FEW AC/ACSL DSNT WSW-N
PRTL SOLAR HALO PK WND 2627/10/ 8/571 58011 10030 20023

SUMMARY FOR WEDNESDAY, JANUARY 4, 2017

TEMPERATURE (DEGREES F)
MAX…..44   NORMAL…..34
MIN…..30   NORMAL…..18
MEAN….37   NORMAL…..26

DEPARTURE FROM 30-YEAR NORMAL…………………..+11
TOTAL DEPARTURE FOR THE MONTH…………………..+40 [+9.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..28   DEPARTURE………-11
TOTAL HEATING UNITS FOR THE MONTH………….114   DEPARTURE………-40
TOTAL HEATING UNITS FOR THE SEASON………..2146   DEPARTURE……..-312
TOTAL HEATING UNITS LAST SEASON TO DATE……1797   DIFFERENCE…….+349

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….41 WNW AT 8:40 P.M.
ASOS……………………42 WNW AT 8:41 P.M.
DAVIS…………………..37 W   AT 8:40 P.M. RMY 45
FASTEST MILE FOR YESTERDAY…………………29 WNW AT 8:46 P.M.*
MAXIMUM 2-MINUTE ASOS AVERAGE………………30 WNW AT 8:42 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..30 W   AT 8:42 P.M.
AVERAGE WIND SPEED AND DIRECTION………….12.1 SW
ASOS………………….11.5
DAVIS…………………10.9 WSW [251 deg.] *Last of several occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.03  DEPARTURE……-0.11
ASOS…………..0.03
TOTAL PRECIPITATION FOR THE MONTH……….1.34  DEPARTURE……+0.76
ASOS…………..1.40
TOTAL PRECIPITATION FOR THE YEAR………..1.34  DEPARTURE……+0.76
ASOS…………..1.40

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……..TRACE  DEPARTURE…….-0.6
TOTAL SNOWFALL FOR THE MONTH…………..TRACE  DEPARTURE…….-2.3
TOTAL SNOWFALL FOR THE SEASON……………7.8  DEPARTURE……-10.5

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER-JANUARY 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/+2/0.00/0.0/445/80           37 WNW AERO 39 WNW RMY 40
12/4  39/27/33/-2/0.00/0.0/355/64           25 NW  AERO 25 NW  RMY N/A
12/5  36/27/32/-3/0.13/0.4/000/00           26 W   AERO 25 W   RMY 29
12/6  42/30/36/+1/0.00/0.0/392/71           22 W   AERO 21 W   RMY N/A
12/7  39/34/37/+3/0.10/0.0/000/00           21 E   AERO 21 E   RMY N/A
12/8  40/29/35/+1/0.00/0.0/033/06           30 W   AERO 31 W   RMY 33
12/9  35/21/28/-6/0.00/0.0/549/100          35 W   AERO 36 WNW RMY 34
12/10 27/17/22/-11/0.00/0.0/544/99          26 WNW AERO 27 WNW RMY 29
12/11 33/16/25/-8/0.06/0.4/411/75           17 SSW AERO 15 SW  RMY N/A
12/12 41/27/34/+1/0.35/0.9/038/07           29 ESE AERO 29 SE  RMY 30
12/13 41/30/36/+4/0.00/0.0/427/78           25 WSW AERO 25 W   RMY 27
12/14 40/26/33/+1/0.00/0.0/530/97           30 WNW AERO 31 WNW RMY N/A
12/15 29/13/21/-11/T/T/420/77               50 W   AERO 62 W   RMY 56
12/16 18/01/10/-21/0.00/0.0/485/89          39 WNW AERO 51 WNW RMY N/A
12/17 36/18/27/-4/0.60/4.3/000/00           25 SSW AERO 28 SSW RMY N/A
12/18 55/30/43/+12/0.05/0.0/000/00          47 WSW AERO 53 S   RMY 53
12/19 30/17/24/-6/0.00/0.0/273/50           26 WNW*AERO 28 NW  RMY 26
12/20 32/13/23/-7/0.00/0.0/359/66           28 SSE AERO 29 SSW RMY N/A
12/21 40/25/33/+3/0.00/0.0/354/65           28 SSE AERO 28 SSW RMY 30
12/22 38/29/34/+5/T/T/033/06                28 SSE AERO 29 S   RMY 30
12/23 44/29/37/+8/0.00/0.0/512/94           25 WNW AERO 25 WNW RMY N/A
12/24 41/34/38/+9/0.39/0.0/033/06           30 SSW AERO 31 SSW RMY 30
12/25 43/25/34/+6/0.00/0.0/545/100          35 NW  AERO 37 NW  RMY 36
12/26 46/20/33/+5/…./0.0/425/78           39 S   AERO 40 S   RMY N/A
12/27 56/35/46/+18/…./0.0/169/31          51 SW  AERO 55 SW  RMY N/A
12/28 40/29/35/+7/0.00/0.0/207/38           31 W   AERO 32 W   RMY 26
12/29 40/28/34/+7/0.87/1.8/000/00           38 NW  AERO 44 NW  RMY 42 TSTM
12/30 37/26/32/+5/0.00/0.0/323/59           46 W   AERO 55 WSW RMY 50
12/31 43/23/32/+5/…./0.0/099/18           46 SSW AERO 51 SSW RMY 50

1/1   41/29/35/+8/…./0.0/…/..           35 W   AERO 36 W   RMY 34
1/2   38/29/34/+7/…./0.0/…/..           21 E   AERO 20 E   RMY N/A
1/3   42/37/40/+14/…./0.0/000/00          39 ENE AERO 41 ENE RMY 34
1/4   44/30/37/+11/…./T/…/..            41 WNW AERO 46 WNW RMY 45

1/5 Low temp since midnight is 23F; normal low is now 18F

DAILY RECORDS FOR DECEMBER 2016
None.

DAILY RECORDS FOR JANUARY 2017
None so far.

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

RECORDS FOR JANUARY 5
HIGH 61F IN 2007
LOW -9F IN 1981
PRECIP 0.98 INS. IN 1993
SNOW 4.5 INS. IN 1891
PEAK GUST 70 MPH WNW IN 1959

RECORDS FOR JANUARY 6
HIGH 66F IN 2007
LOW -14F IN 1896
PRECIP 3.10 INS. IN 1889 [RECORD FOR MONTH] SNOWFALL 7.5 INS. IN 1893
PEAK GUST 70 MPH WNW IN 1959

TODAY’S REPORT PREPARED BY: Jonathan O’Brien