Thursday, December 6, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, DECEMBER 6, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

WESTERLY WINDS AND CLOUD COVER INCREASING IN
THE AFTERNOON….

Visibility remained at 40 miles since this morning, due
to a distant haze. Winds frequently exceeding 20 mph from
the west have kept temperatures below seasonal averages,
advecting colder air from further inland. Another contributor
is the increasing afternoon clouds from almost clear skies
this morning. This is accompanied by a decrease in pressure,
which is a little over 2 millibars since the 10 A.M. observation.
The high temperature so far today is 37F, 5 degrees below the
daily normal of 42F. The low since midnight is 24F, 3 degrees
below the normal minimum of 27F.

BHO Wettest Novembers, inches (1886-2018):

1) 10.32 in 2018
2) 9.78 in 1983
3) 9.29 in 1945
4) 9.17 in 1972
5) 8.95 in 1895
6) 8.93 in 1988
7) 8.79 in 1963

BHO Wettest Falls (Sep-Nov), inches (1886-2018):

1) 25.42 in 2018
2) 23.18 in 2005
3) 23.13 in 1996
4) 22.47 in 1888
5) 20.65 in 2011
6) 20.64 in 1932
7) 20.08 in 1962
PRELIMINARY STATS FOR NOVEMBER 2018

TEMPERATURE, Deg. F
Avg. Max. 45.2 [-4.8] Avg. Min. 32.4 [-1.1] Mean 38.8 [-2.9] 24-hour corrected mean: 38.6
Max. for month: 65F on the 1st and 2nd
Min. for month: 9F on the 22nd and 23rd

HEATING DEGREE DAYS
Total heating units: 776 [+78] Total for the season: 1320 [+351] Total for last season: 969

PRECIPITATION, Inches
Total: 10.32 in. [+5.56] Greatest in 24 hrs: N/A

SNOWFALL, Inches
Total: 7.6 in. [+5.3] Greatest in 24 hrs: N/A

WIND, mph
Avg. uncorrected wind speed: N/A
Avg. corrected wind speed: N/A
Prevailing wind direction: N/A
Peak gust and direction: N/A

SUNSHINE:
Campbell-Stokes card minutes: N/A
Astronomical total minutes: N/A

Today’s Observations:

7 A.M.
Weather: Scattered altocumulus, few cumulus in all
directions
Temperature: 24F; Dew Point: 17F; Wind: W at 10G14 kts
Sea-level pressure: 30.10 ins. Hg, rising slowly
Visibility: 40 miles
6-hr Max temp: 27F
6-hr Min temp: 24F
24-hr Precip: 0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1155 100 SCT 40 193/24/17/2710G14/010/ FEW CU
ALQDS/ 8/170 53004 10027 20024

10 A.M.
Weather: Scattered cirrostratus
Temperature: 31F; Dew Point: 20F; Wind: W at 14G17 kts
Sea-level pressure: 30.12 ins. Hg, rising steadily
Visibility: 40 miles, distant haze
3-hr Precip: 0.00 ins.
3-hr snowfall: 0.0 ins.
BHO SA 1455 250 SCT 40 200/31/20/2714G27/012/ DSNT HZ
ALQDS/ 8/008 51007

1 P.M.
Weather: Broken cirrostratus, few cumulus in all
directions
Temperature: 36F; Dew Point: 19F; Wind: W at 16G22 kts
Sea-level pressure: 30.06 ins. Hg, falling rapidly
Visibility: 40 miles
6-hr Max temp: 37F
6-hr Min temp: 24F
6-hr Precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1755 E250 BKN 40 179/36/19/2716G22/006/ FEW CU
ALQDS/ 8/108 56021 10037 20024

SUMMARY FOR WEDNESDAY, DECEMBER 5, 2018

TEMPERATURE (DEGREES F)
MAX…..33   NORMAL…..42
MIN…..18   NORMAL…..27
MEAN….26   NORMAL…..35

DEPARTURE FROM 30-YEAR NORMAL……………………-9
TOTAL DEPARTURE FOR THE MONTH……………………+3 [+0.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..39   DEPARTURE………+9
TOTAL HEATING UNITS FOR THE MONTH………….143   DEPARTURE………-3
TOTAL HEATING UNITS FOR THE SEASON………..1463   DEPARTURE……..+55
TOTAL HEATING UNITS LAST SEASON TO DATE……1094   DIFFERENCE……+369

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..16 NNW AT  1:32 A.M.
AERO…………………….15 NNW AT  1:32 A.M.
ASOS…………………….16 N   AT  1:34 A.M.
DAVIS……………………16 N   AT  1:33 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………….11 NNW AT  7:10 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….12 N   AT  7:11 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………12 NNW AT  1:34 A.M.
AVERAGE WIND SPEED AND DIRECTION……………5.5 NW
ASOS……………………5.6
DAVIS…………………..5.5 NW [343 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE…….-0.17
ASOS…………..0.01
TOTAL PRECIPITATION FOR THE MONTH……….1.04  DEPARTURE…….+0.22
ASOS…………..0.81
TOTAL PRECIPITATION FOR THE YEAR……….64.41  DEPARTURE……+15.25
ASOS………….66.44

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……..-0.3
TOTAL SNOWFALL FOR THE MONTH…………….0.0  DEPARTURE……..-1.4
TOTAL SNOWFALL FOR THE SEASON……………7.6  DEPARTURE……..+3.6

PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/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

11/01 65/49/57/+11/…./006/01         25 SSW AERO 24 SSW RMY N/A
11/02 65/52/59/+13/…./000/00         37 SSW AERO 41 SSW RMY N/A
11/03 64/42/53/+7/…./148/24          59 W   AERO 60 W   RMY 58
11/04 52/37/45/0/…./588/96           31 W   AERO 30 W   RMY N/A
11/05 49/40/45/0/…./000/00           30 ENE AERO 29 ENE RMY 28
11/06 58/45/52/+7/…./000/00          29 SSW AERO 29 SSW RMY 31
11/07 60/50/55/+10/…./593/98         30 WSW AERO 30 WSW RMY 32
11/08 52/37/45/+1/…./470/78          29 WNW AERO 26 WNW RMY 23
11/09 48/34/41/-3/…./240/40          43 E   AERO 40 E   RMY 42
11/10 45/32/39/-5/…./000/00          45 W   AERO 47 WNW RMY 46
11/11 43/30/37/-6/0.00/596/100         32 WNW AERO 30 W   RMY 32
11/12 48/27/38/-5/0.00/475/80          18 SW  AERO 18 SW  RMY N/A
11/13 52/37/45/+2/…./000/00          44 WNW AERO 44 WNW RMY 48
11/14 37/20/29/-13/…./471/80         45 WNW AERO 50 WNW RMY 50
11/15 30/19/25/-17/…./000/00         33 E   AERO 36 E   RMY N/A
11/16 41/30/36/-6/…./000/00          43 E   AERO 44 ENE RMY N/A
11/17 45/34/40/-1/0.00/111/19          28 W   AERO 27 W   RMY 28
11/18 40/30/35/-6/0.00/157/27          21 W   AERO 21 W   RMY M
11/19 38/33/36/-5/…./000/00          16 E   AERO 14 E   RMY N/A
11/20 38/31/35/-5/…./000/00          30 NE  AERO 30 NE  RMY N/A
11/21 39/20/30/-10/…./081/14         40 WNW AERO 46 WNW RMY 47
11/22 20/09/15/-25/…./567/99         36 NW  AERO 41 NW  RMY 42
11/23 30/09/20/-19/0.00/548/96         25 SW  AERO 25 SW  RMY 27
11/24 43/24/34/-5/…./302/53          27 SW  AERO 27 ESE RMY N/A
11/25 43/40/42/+3/…./000/00          39 ENE AERO 39 ENE RMY 39
11/26 44/39/42/+4/…./000/00          45 E   AERO 44 E   RMY 45
11/27 45/33/39/+1/…./141/25          44 ENE AERO 44 ENE RMY N/A
11/28 39/31/35/-3/…./180/32          37 WNW AERO 41 WNW RMY 42
11/29 43/30/37/0/…./315/56           40 NW  AERO 41 NW  RMY 44
11/30 39/27/33/-4/0.00/370/66          18 NW  AERO 16 NW  RMY N/A

DAILY RECORDS FOR NOVEMBER 2017

11/22/18: DAILY RECORD LOW MAXIMUM TEMPERATURE OF 20F,
BREAKS PREVIOUS RECORD OF 26F SET IN 1972 AND 2008
11/22/18: DAILY RECORD LOW MINIMUM TEMPERATURE OF 9F,
BREAKS PREVIOUS RECORD OF 12F SET IN 1987
11/23/18: DAILY RECORD LOW MINIMUM TEMPERATURE OF 9F,
TIES PREVIOUS RECORD OF 9F SET IN 1888

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/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 41/28/35/-2/0.00/…/..          20 NNW AERO 18 NNW RMY N/A
12/02 52/35/44/+8/1.04/…/..          28 ESE AERO 25 ESE RMY 27
12/03 54/38/46/+10/0.00/…/..         35 W   AERO 35 W   RMY 38
12/04 38/23/31/-4/0.00/…/..          30 WNW AERO 31 WNW RMY 33
12/05 33/18/26/-9/0.00/…/..          16 NNW AERO 15 NNW RMY N/A

12/06 Low temp since midnight is 24F; normal low is 27F

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

RECORDS FOR DECEMBER 6
HIGH 70 IN 2001
LOW 5 IN 1901,1935
PRECIP 2.78 INS. IN 2003
SNOWFALL 17.0 INS. IN 2003
PEAK GUST 74 MPH NW IN 1981

RECORDS FOR DECEMBER 7
HIGH 74 IN 1998
LOW 6 IN 1906
PRECIP 1.67 INS. IN 1953
SNOWFALL 6.3 INS. IN 2003
PEAK GUST 76e SE IN 1976

TODAY’S REPORT PREPARED BY: Benjamin Turner