Sunday, September 6, 2020

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

SUNDAY, SEPTEMBER 6, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

ANOTHER COOL AND DRY EARLY-FALL DAY….

We observed partly cloudy conditions throughout the day,
with an average visibility of 70 miles. Dew points stayed
in the mid 50’s, making conditions perfect for being out
of doors. A light wind has been coming in from the south-
west, at an average of 5 mph. All together with a mix of
sun and clouds, this has been a very enjoyable observing
day.

The high so far today is 78F, 3 degrees above the daily
normal max of 75F. The low since midnight is 58F, which is
the same as the normal low of 58F.

PRELIMINARY STATS FOR AUGUST 2020

TEMPERATURE, Deg. F
Avg. Max. 82.5 [+3.3] Avg. Min. 64.3 [+2.5] Mean      73.4 [+2.9] 24-hour corrected mean: 72.3
Max. for month: 94F on the 10th
Min. for month: 54F on the 31st

HEATING DEGREE DAYS
Total heating units:     2 [-14] Total for the season:    3 [-222] Total for last season:  12

COOLING DEGREE DAYS
Total cooling units:    270  [+84] Total for the season:   757  [+220] Total for last season:  622

PRECIPITATION, Inches
Total: 3.74 [-0.29] Greatest in 24 hrs: N/A

WIND, mph
Avg. uncorrected wind speed: 10.0 mph
Avg. corrected wind speed:   10.6 mph
Prevailing wind direction:   SSW [12%] Peak gust and direction:     67 SSE on the 4th

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

Today’s Observations:

7 A.M.
Weather: Broken altocumulus
Temperature: 63F; Dew Point: 53F; Relative Humidity: 73%
Wind: SW at 7 kts
Sea-level pressure: 30.19 ins. Hg: rising steadily
Visibility: 75 miles
6-hr Max temp: 63F
6-hr Min temp: 58F
24-hr Precip: 0.00 ins.
BHO SA 1155 140 BKN 75 226/63/53/2307/019/ 8/070 51008
10063 20058

10 A.M.
Weather: Scattered altocumulus and cirrocumulus
Temperature: 73F; Dew Point: 53F; Relative Humidity: 49%
Wind: SW at 3 kts, light and variable
Sea-level pressure: 30.18 ins. Hg: rising then falling
Visibility: 75 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 70 SCT 250 SCT 75 221/73/53/2303/018/ WND L/V/
8/079 55005

1 P.M.
Weather: Scattered Cumulus/stratocumulus
Temperature: 75F; Dew Point: 54F; Relative Humidity: 49%
Wind: WSW 8 kts
Sea-level pressure: 30.19 ins. Hg: rising steadily
Visibility: 75 miles
6-hr Max temp: 78F
6-hr Min temp: 63F
6-hr Precip: 0.00 ins.
BHO SA 1755 50 SCT 75 226/75/54/2508/019/ 8/800 50005
10078 20063

SUMMARY FOR SATURDAY, SEPTEMBER 5, 2020

TEMPERATURE (DEGREES F)
MAX…..76   NORMAL…..76
MIN…..55   NORMAL…..58
MEAN….66   NORMAL…..67

DEPARTURE FROM 30-YEAR NORMAL……………. -1
TOTAL DEPARTURE FOR THE MONTH……………. +4 [+0.6 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………  1  DEPARTURE……-2
TOTAL COOLING UNITS FOR THE MONTH………… 17  DEPARTURE……-1
TOTAL COOLING UNITS FOR THE SEASON………..774  DEPARTURE….+219
TOTAL COOLING UNITS LAST SEASON TO DATE……634  DEPARTURE….+140

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..25 W   AT  3:32 P.M.
AERO…………………….25 W   AT  3:24 P.M.
ASOS…………………….25 W   AT  3:32 P.M.
DAVIS……………………26 WNW AT  3:49 P.M.
RMY 24  MERLIN 24
FASTEST MILE FOR YESTERDAY………………….19 W   AT  3:50 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….18 W   AT  3:50 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………19 W   AT  3:50 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..10.6 NW
ASOS…………………..10.8
DAVIS………………….10.8 WNW [288 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE….-0.12
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….0.22  DEPARTURE….-0.36
ASOS…………..0.24
TOTAL PRECIPITATION FOR THE YEAR……….33.03  DEPARTURE….-2.57
ASOS………….33.82

PRELIMINARY CLIMATE SUMMARY FOR AUGUST 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

08/01  87/66/77/+5/0.00/866/100            18 S    AERO 21 S    RMY 19
08/02  85/69/77/+5/0.02/320/37             36 S    AERO 37 S    RMY 38
08/03  91/75/83/+11/0.00/715/83            36 WSW  AERO 38 SW   RMY 36
08/04  83/71/77/5/0.21/094/11              67 SSE  AERO 71 S    RMY 70
08/05  90/68/79/+7/0.00/668/78             28 SW   AERO 30 SW   RMY 29
08/06  84/65/75/3/0.00/701/82   20 W    AERO 17 W    RMY 19
08/07  79/65/72/0/T/136/16                 16 NE   AERO 16 NE   RMY N/A
08/08  83/64/74/+2/0.00/612/72             20 S    AERO 20 S    RMY 19
08/09  90/65/78/+6/0.00/661/78             26 SSW  AERO 26 SSW  RMY 26
08/10  94/69/82/+11/0.00/727/86            22 W    AERO 20 W    RMY 20
08/11  92/72/82/+11/0.00/708/84            31 SSW  AERO 35 SSW  RMY 31  TSTM
08/12  93/74/84/+13/0.00/647/77            22 SSW  AERO 22 SW   RMY 19
08/13  88/71/80/+9/0.00/528/63             18 ENE  AERO 18 NE   RMY 18
08/14  82/67/75/+4/0.00/618/74             23 ENE  AERO 23 ENE RMY N/A
08/15  67/62/65/-6/T/000/00                33 NNE  AERO 32 NNE  RMY N/A
08/16  69/62/66/-5/…./000/00             26 ENE  AERO 28 ENE  RMY 26
08/17  73/59/66/-5/…./339/41             25 NE   AERO 24 NE   RMY N/A
08/18  84/63/74/+3/…./784/95             23 W    AERO 23 W    RMY 24
08/19  81/59/70/0/0.03/526/64              26 W    AERO 28 W    RMY 27
08/20  80/56/68/-2/0.00/804/98             22 W    AERO 21 W    RMY 22
08/21  88/61/75/+5/0.00/719/88             28 SW   AERO 26 SW   RMY 28
08/22  85/66/76/+6/0.26/521/64             18 NNE  AERO 16 S    RMY 16
08/23  89/63/76/+6/2.21/552/68             60 WNW  AERO 53 WNW  RMY 58  TSTM HAIL
08/24  87/67/77/+7/0.00/493/61             18 S    AERO 18 S    RMY 19  TSTM
08/25  86/65/76/+7/0.01/492/61             35 NNW  AERO 37 NNW  RMY 35
08/26  74/56/65/-4/0.00/780/97             29 NW   AERO 32 NW   RMY N/A
08/27  68/57/63/-6/0.33/008/01             18 SSE  AERO 20 SSE  RMY 20  TSTM
08/28  80/59/70/+1/0.00/559/70             20 W    AERO 20 W    RMY N/A
08/29  74/65/70/+1/0.06/000/00             32 W    AERO 32 W    RMY N/A
08/30  75/57/66/-2/0.00/793/100            36 W    AERO 36 W    RMY N/A
08/31  75/54/65/-3/0.00/569/72             20 S    AERO 20 S    RMY 20

DAILY RECORDS FOR AUGUST 2020

8/23/20: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 89F,
BREAKS PREVIOUS RECORD of 88F SET IN 1918, 1947, 1949, 1996

8/23/20: DAILY RECORD PRECIPITATION OF 2.21 INS,
BREAKS PREVIOUS RECORD OF 2.09 INS SET IN 2010

8/23/20: DAILY RECORD PEAK WIND GUST OF 60 MPH,
TIES PREVIOUS RECORD OF 60 MPH SET IN 1940

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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

09/01  76/59/68/0/0.00/…/..              22 SSE  AERO 21 SE   RMY 20
09/02  69/59/64/-4/…/…/..              23 SSE  AERO 23 SSE  RMY 24
09/03  75/66/71/+4/…/…/..              22 SSW  AERO 21 SSW  RMY n/a
09/04  82/62/72/+5/0.00/…/..             26 WNW  AERO 26 WNW  RMY 25
09/05  76/55/66/-1/0.00/…/..             25 W    AERO 25 W    RMY 24

09/06 The low since midnight is 58F, the daily normal low is 58F

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

RECORDS FOR SEPTEMBER 6
HIGH 92F IN 1900, 2018
LOW 39F IN 1888
PRECIP 3.19 INCHES IN 1890
PEAK GUST 78e MPH SE IN 1979 (TROPICAL STORM DAVID)

RECORDS FOR SEPTEMBER 7
HIGH 92F IN 2007, 2015
LOW 40F IN 1888
PRECIP 2.95 INCHES IN 1891
PEAK GUST 58e MPH W IN 1941

TODAY’S REPORT PREPARED BY: Benjamin Turner