Tuesday, December 10, 2019

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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, DECEMBER 10, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

MILD AND WET CONDITIONS CONTINUE AHEAD OF A COLD FRONT….

The first half of the day was actually pretty nice with a little
bit of sunshine this morning and temperatures well into the 50s,
however by early afternoon clouds have returned along with rain.

After the rather gusty day yesterday featuring a peak gust of
53 mph, today has seen lighter winds with gusts to 20-25mph most
of today.

The high so far today is 58F, which is 17 degrees above the
daily normal maximum of 41F. The low since midnight is 54F,
which is an impressive 28 degrees above the normal minimum of 26F.

PRELIMINARY STATS FOR NOVEMBER 2019

TEMPERATURE, Deg. F
Avg. Max. 46.0 [-4.0] Avg. Min. 30.3 [-3.2] Mean      38.2 [-3.5] 24-hour corrected mean: 38.0
Max. for month: 67F on the 1st
Min. for month: 15F on the 13th

HEATING DEGREE DAYS
Total heating units:    761 [+99] Total for the season:  1237 [-24] Total for last season: 1319

PRECIPITATION, Inches
Total: 3.74 [-1.02] Greatest in 24 hrs: N/A

SNOWFALL, Inches
Total: 0.1 [-2.2] Greatest in 24 hrs: 0.1 ins. on the 12th

WIND, mph
Avg. uncorrected wind speed: 12.5 mph
Avg. corrected wind speed:   12.9 mph
Prevailing wind direction:   W [16%] Peak gust and direction:     67 S on the 1st

SUNSHINE:
Campbell-Stokes card minutes: 8652 minutes of possible 17010 or 51%
Astronomical total minutes: 8985 minutes of possible 17640 or 51%

Today’s Observations:

7 A.M.
Weather: Broken altocumulus, broken cirrus
Temperature: 54F; Dew Point: 52F; Wind: SSW at 14G22 kts
Sea-level pressure: 29.74 ins. Hg, rising, then more rapidly
Visibility: 30 miles, hazy
6-hr Max temp: 56F
6-hr Min temp: 54F
24-hr Precip:  0.65 ins.
24-hr Snowfall: 0.0 ins.
BHO SA 1155 E140 BKN 200 BKN 250 –BKN 30 070/54/52/2214G22/974/ FEW
STRAFRA ALQDS HAZY/ 8/732 53011 6/// 70065 10056 20054

10 A.M.
Weather: Broken altocumulus, broken cirrus
Temperature: 56F; Dew Point: 53F; Wind: SSW at 14G19 kts
Sea-level pressure: 29.77 ins. Hg, falling, then more slowly
Visibility: 30 miles, hazy
3-hr Precip: 0.00 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1455 E140 BKN 200 BKN 250 –OVC 30 081/56/53/2214G19/977/ FEW
STRAFRA ALQDS HAZY/ 8/772 51011

1 P.M.
Weather: Scattered Stratus Fractus, Overcast altostratus
Temperature: 57F; Dew Point: 53F; Wind: SW at 15G21 kts
Sea-level pressure: 29.72 ins. Hg, falling, then more slowly
Visibility: 20 miles, hazy
6-hr Max temp: 58F
6-hr Min temp: 54F
6-hr Precip:  0.00 ins.
6-hr Snowfall: 0.0 ins.
BHO SA 1755 13 SCT E80 OVC 20 063/57/53/2315G21/972/ HAZY/ 8/75/ 56018
10058 20054

SUMMARY FOR MONDAY, DECEMBER 9, 2019

TEMPERATURE (DEGREES F)
MAX…..57   NORMAL…..41
MIN…..36   NORMAL…..26
MEAN….47   NORMAL…..34

DEPARTURE FROM 30-YEAR NORMAL…………………+13
TOTAL DEPARTURE FOR THE MONTH…………………-46 [-5.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………18  DEPARTURE…….-13
TOTAL HEATING UNITS FOR THE MONTH…………..315  DEPARTURE…….+46
TOTAL HEATING UNITS FOR THE SEASON…………1552  DEPARTURE…….+12
TOTAL HEATING UNITS LAST SEASON TO DATE…….1615  DEPARTURE…….-63

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..53 S   AT  1:15 P.M.
AERO…………………….52 S   AT  1:01 P.M.
ASOS…………………….53 S   AT  1:15 P.M.
DAVIS……………………55 S   AT  1:10 P.M. RMY 54
FASTEST MILE FOR YESTERDAY………………….41 S   AT  3:10 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….38 S   AT  1:04 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………37 S   AT  3:09 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..22.8 S
ASOS…………………..21.2
DAVIS………………….21.4 S  [189 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.65  DEPARTURE……+0.48
ASOS…………..0.85
TOTAL PRECIPITATION FOR THE MONTH……….3.12  DEPARTURE……+1.64
ASOS…………..3.45
TOTAL PRECIPITATION FOR THE YEAR……….52.20  DEPARTURE……+2.18
ASOS………….52.85

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE…….-0.4
TOTAL SNOWFALL FOR THE MONTH……………13.2  DEPARTURE……+10.3
TOTAL SNOWFALL FOR THE SEASON…………..13.3  DEPARTURE…….+7.8

PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER 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

11/01  67/35/51/+5/0.12/0.0/534/86            67 S   AERO M  M   RMY N/A
11/02  50/31/41/-5/0.00/0.0/612/99            17 WNW AERO 14 W   RMY N/A
11/03  53/35/44/-2/0.00/0.0/567/92            25 WSW AERO 23 W   RMY 26
11/04  53/33/43/-2/0.00/0.0/546/89            24 S   AERO 20 S   RMY 24
11/05  54/44/49/+4/0.33/0.0/000/00            22 S   AERO 18 WNW RMY 28
11/06  51/36/44/-1/0.00/0.0/596/98            28 WSW AERO 23 W   RMY 27
11/07  55/38/47/+2/0.27/0.0/000/00            30 S   AERO 26 SSW RMY 32
11/08  38/23/31/-13/0.00/0.0/555/92           38 NW  AERO 37 WNW RMY 44
11/09  39/20/30/-14/0.00/0.0/583/97           22 S   AERO 18 S   RMY N/A
11/10  51/30/41/-3/0.00/0.0/174/29            30 SW  AERO 30 SW  RMY 31
11/11  52/39/46/+3/T/0.0/000/00               23 NE  AERO 22 NE  RMY 23
11/12  42/20/31/-12/0.08/0.1/000/00           37 WNW AERO 37 WNW RMY 41
11/13  28/15/22/-21/0.00/0.0/592/100          32 WNW AERO 32 WNW RMY 35
11/14  36/17/28/-14/0.00/0.0/136/23           18 SW  AERO 17 SW  RMY 20
11/15  51/32/42/0/0.00/0.0/553/94             25 WNW AERO 25 WNW RMY N/A
11/16  35/22/29/-13/0.00/0.0/580/99           35 NNW AERO 35 NNW RMY N/A
11/17  40/21/31/-10/T/T/000/00                28 ENE AERO 27 ENE RMY 29
11/18  36/32/34/-7/…./0.0/000/00            28 NNE AERO 29 N   RMY 31
11/19  42/36/39/-2/…./0.0/000/00            12 SSW AERO  9 NNW RMY N/A
11/20  38/33/36/-4/…./T/000/00              20 NW  AERO 18 NW  RMY 21
11/21  46/30/38/-2/0.00/0.0/536/93            21 NW  AERO 21 NW  RMY N/A
11/22  52/32/42/+2/0.12/0.0/000/00            46 W   AERO 47 W   RMY 47
11/23  44/27/36/-3/0.00/0.0/503/88            29 WNW AERO 29 WNW RMY N/A
11/24  44/35/40/+1/1.49/0.0/000/00            45 N   AERO 44 NE  RMY 46 TSTM
11/25  50/34/42/+3/0.00/0.0/329/58            32 WNW AERO 35 WNW RMY 23
11/26  59/39/49/+11/0.00/0.0/544/96           28 SSW AERO 27 SSW RMY 29
11/27  50/42/46/+8/…./0.0/011/02            30 W   AERO 32 W   RMY N/A TSTM
11/28  48/30/39/+1/…./T/062/11              42 NW  AERO 44 NW  RMY 44
11/29  39/27/33/-4/0.00/0.0/433/77            35 NW  AERO 36 NW  RMY 39
11/30  35/22/29/-8/0.00/0.0/539/96            30 NW  AERO 28 WNW RMY 31

DAILY RECORDS FOR NOVEMBER

11/13/19: DAILY RECORD LOW MAXIMUM TEMPERATURE OF 28F,
BREAKS PREVIOUS RECORD OF 30F SET IN 1920.
It was also the third earliest maximum temperature
colder than 30F on record, behind only 28F on 11/8/1894
and 29F on 11/12/1894.

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

12/01  32/16/24/-13/…./5.8/…/..           33 ENE AERO 32 ENE RMY N/A
12/02  37/25/31/-5/…./2.7/…/..            52 NE  AERO 47 NE  RMY 53
12/03  30/23/27/-9/…./4.6/…/..            32 N   AERO 35 N   RMY 36
12/04  34/22/28/-7/…./0.0/…/..            23 WNW AERO 23 NNW RMY N/A
12/05  41/26/34/-1/…./0.0/…/..            33 NW  AERO 35 NW  RMY 37
12/06  33/23/28/-7/0.02/0.1/…/..            25 NW  AERO 23 NW  RMY 29
12/07  31/18/25/-9/0.00/0.0/…/..            25 NW  AERO 23 NW  RMY N/A
12/08  36/15/26/-8/0.00/0.0/…/..            31 SSW AERO 32 SSW RMY N/A
12/09  57/36/47/+13/…./0.0/…/..           53 S   AERO 52 S   RMY 54

12/10 The low since midnight is 54F, daily normal minimum is 26F

DAILY RECORDS FOR DECEMBER

12/01/19: DAILY RECORD SNOWFALL OF 5.8 INS.,
BREAKS PREVIOUS RECORD OF 2.0 INS. SET IN 1902.

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

RECORDS FOR DECEMBER 10
HIGH 62 IN 1946
LOW -6 IN 1902
PRECIP 1.67 INS. IN 1907
SNOWFALL 6.0 INS. IN 1905
PEAK GUST 66e SW IN 1940

RECORDS FOR DECEMBER 11
HIGH 63 IN 1911
LOW -1 IN 1988
PRECIP 2.36 INS. IN 1992
SNOWFALL 6.0 INS. IN 1894
PEAK GUST 78 S IN 1969

TODAY’S REPORT PREPARED BY: Matt Douglas / Ann Murphy