Wednesday, December 28, 2016

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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, DECEMBER 28, 2016
ALL TIMES ARE IN EASTERN STANDARD TIME

PERIODS OF SUN AND CLOUDS WITH COLDER TEMPERATURES
TODAY AS DRIER AIR BRIEFLY MOVES IN BEFORE THE NEXT STORM…

The strong winds on Friday brought the highest wind gust
of the month so far of 51 mph SW early Friday morning.
Temperatures in the middle 50s topped out at 56F, which was
one short of the record for the date of 57F set in 1895 and
1949. Cooler temperatures began to arrive Friday evening on
a W-WNW wind, and the minimum was 34F at sunrise this morning.
Early morning clouds broke for a while to provide some sun
at mid-day today, before returning later in the afternoon.
A period of virga was observed to the NW around the time of
the 1 PM EST observation, though no precipitation was recorded
on the hill. Drier air swept in today dropping the dew point
from the low 50s Friday morning to the middle teens this
afternoon. Visibility has climbed all day reaching 80 miles
at 1 PM. With a mean wind speed of 22.5 mph and a peak gust
of 51 mph, Friday was the windiest day at BHO since April 7th,
which had a mean of 24.3 mph and a peak gust of 53 mph. The
warmth yesterday has turned the month around to the warm
side of normal.

7 A.M.
Weather: Overcast stratocumulus, few lower stratocumulus N-SE,
breaks in overcast distant all quadrants
Temperature: 34F; Dew Point: 25F; Wind: W at 8 kts,
Sea-level pressure: 29.96 ins. Hg, rising, then more quickly
Visibility: 45 miles
6-hr Max temp: 35F
6-hr Min temp: 34F
24-hr precip: 0.00 in.
24-hr snowfall: 0.0 in.
BHO SA 1155 E50 OVC 45 147/34/25/2808/996/ FEW LWR SC N-SE
BINOVC DSNT ALQDS/ 8/5// 53021 10035 20034

10 A.M.
Weather: Scattered cumulus and stratocumulus, scattered
altocumulus, few altocumulus lenticularis SW-NW
Temperature: 37F; Dew Point: 22F; Wind: WNW at 13G22 kts,
Peak Wind: 30 mph WNW at 9:42 A.M. EST
Sea-level pressure: 30.02 ins. Hg, rising steadily
Visibility: 70 miles
BHO SA 1455 35 SCT 65 SCT 70 166/37/22/2913G22/002/ FEW ACSL
SW-NW PK WND 2926/42/ 8/840 52019

1 P.M.
Weather: Scattered stratocumulus, broken altocumulus, virga
distant WNW-NNW
Temperature: 38F; Dew Point: 18F; Wind: WNW at 10 kts,
Sea-level pressure: 30.01 ins. Hg, falling, then rising, now lower
Visibility: 80 miles, visibility NW 70
6-hr Max temp: 39F
6-hr Min temp: 34F
BHO SA 1755 50 SCT E65 BKN 80 162/38/18/2910/001/ VIRGA DSNT
WNW-NNW VSBY NW 70/ 8/570 55004 10039 20034

SUMMARY FOR TUESDAY, DECEMBER 27, 2016

TEMPERATURE (DEGREES F)
MAX…..56   NORMAL…..36
MIN…..35   NORMAL…..20
MEAN….46   NORMAL…..28

DEPARTURE FROM 30-YEAR NORMAL…………………..+18
TOTAL DEPARTURE FOR THE MONTH…………………..+15 [+0.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..19   DEPARTURE………-18
TOTAL HEATING UNITS FOR THE MONTH………….875   DEPARTURE………-17
TOTAL HEATING UNITS FOR THE SEASON………..1905   DEPARTURE……..-249
TOTAL HEATING UNITS LAST SEASON TO DATE……1525   DIFFERENCE…….+380

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….51 SW  AT  5:38 A.M. *
ASOS……………………56 SSW AT  4:10 A.M.
DAVIS…………………..55 SSW AT  4:08 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………41 SW  AT  5:39 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………39 SW  AT  5:39 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..38 SSW AT  5:39 A.M.
AVERAGE WIND SPEED AND DIRECTION………….22.5 SW
ASOS………………….22.4
DAVIS…………………19.7 SSW [206 Deg.] * Last of several occurrences.

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.14
ASOS…………..0.01
TOTAL PRECIPITATION FOR THE MONTH……….1.90  DEPARTURE……-2.42
ASOS…………..2.15
TOTAL PRECIPITATION FOR THE YEAR……….38.87  DEPARTURE…..-13.98
ASOS………….39.58

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE…….-0.5
TOTAL SNOWFALL FOR THE MONTH…………….6.0  DEPARTURE…….-5.2
TOTAL SNOWFALL FOR THE SEASON……………6.0  DEPARTURE…….-7.8

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/+2/0.00/0.0/445/80           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/…/..           25 WNW AERO 25 WNW RMY N/A
12/24 41/34/38/+9/0.39/0.0/…/..           30 SSW AERO 31 SSW RMY 30
12/25 43/25/34/+6/0.00/0.0/…/..           35 NW  AERO 37 NW  RMY 36
12/26 46/20/33/+5/…./0.0/…/..           39 S   AERO 40 S   RMY N/A
12/27 56/35/46/+18/…./0.0/…/..          51 SW  AERO 55 SW  RMY N/A

12/28 Low temp since midnight is 34F; normal low is now 20F

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

RECORDS FOR DECEMBER 28
HIGH 60 IN 1982
LOW -2 IN 1933
PRECIP 2.16 INS. IN 1967
SNOWFALL 9.5 INS. IN 1967
PEAK GUST 89 MPH SSE IN 1983

RECORDS FOR DECEMBER 29
HIGH 72 IN 1984
LOW -19 IN 1933 (RECORD FOR DECEMBER)
PRECIP 1.91 INS. IN 1945
SNOWFALL 18.4 INS. IN 1945
PEAK GUST 95 MPH S IN 1966 (RECORD FOR DECEMBER)

TODAY’S REPORT PREPARED BY: Mike Iacono