Tuesday, October 20, 2020

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

TUESDAY, OCTOBER 20, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

FOGGY AND COOL WITH A LIGHT SOUTHEASTERLY WIND….

Today we observed a limited morning visibility due
to fog, then haze later on in the day. This yielded
a visibility of a 1/16th mile, then 25 miles later
on in the day. Wind is southeasterly, with a max gust
of 22 mph. The average speed slightly exceeded 10 mph.
Weather conditions are overcast, with some breaks to
the west following the 1 P.M. observation.

The high so far today is 66F, 7 degrees above the daily
normal minimum of 59F. The low since midnight is 49F,
8 degrees above the normal low of 41F.

Today’s Observations:

7 A.M.
Weather: Fog
Temperature: 52F; Dew Point: 52F; Relative Humidity: 100%
Wind: S at 11 kts
Sea-level pressure: 30.28 ins. Hg: rising, then more slowly
Visibility: 1/16th mile, fog
6-hr Max temp: 52F
6-hr Min temp: 49F
24-hr Precip: 0.00 ins.
BHO SA 1155 X W3 1/16F 253/52/52/1711/028/ 8//// 53002
10052 20049

10 A.M.
Weather: Overcast stratus
Temperature: 56F; Dew Point: 56F; Relative Humidity: 100%
Wind: S at 7 kts
Sea-level pressure: 30.29 ins. Hg: falling then rising
Visibility: 4 miles, fog
3-hr Precip: 0.00 ins.
BHO SA 1455 30 OVC 4F 256/56/56/1807/029/ 8/6// 50003

1 P.M.
Weather: Overcast altostratus
Temperature: 64F; Dew Point: 58F; Relative Humidity: 80%
Wind: SSE at 8 kts
Sea-level pressure: 30.26 ins. Hg: falling steadily
Visibility: 25 miles, thin fog
6-hr Max temp: 66F
6-hr Min temp: 52F
6-hr Precip: 0.00 inches
BHO SA 1755 60 OVC 25 245/64/58/2208/026/ HAZY/ 8/01/
58011 10066 20052

SUMMARY FOR MONDAY, OCTOBER 19, 2020

TEMPERATURE (DEGREES F)
MAX…..61   NORMAL…..59
MIN…..46   NORMAL…..42
MEAN….54   NORMAL…..50

DEPARTURE FROM 30-YEAR NORMAL……………..+4
TOTAL DEPARTURE FOR THE MONTH…………….+46 [+2.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….11  DEPARTURE….. -4
TOTAL HEATING UNITS FOR THE MONTH…………170  DEPARTURE…..-51
TOTAL HEATING UNITS FOR THE SEASON………..268  DEPARTURE…..-95
TOTAL HEATING UNITS LAST SEASON TO DATE……310  DEPARTURE…..-42

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………. 0  DEPARTURE…… 0
TOTAL COOLING UNITS FOR THE MONTH…………. 1  DEPARTURE….. -4
TOTAL COOLING UNITS FOR THE SEASON………..831  DEPARTURE….+229
TOTAL COOLING UNITS LAST SEASON TO DATE……682  DEPARTURE….+149

PEAK WIND GUST FOR YESTERDAY (MPH)
420C/Official……………16 ESE AT   3:04 P.M.
AEROVANE (south tower)……16 SSE AT   7:45 P.M.
ASOS……………………16 E   AT   3:14 P.M.
DAVIS #1………………..16 ESE AT   9:41 P.M.
DAVIS #2 (south tower)……19 SSE AT   7:36 P.M.
RMY…………………….21
MERLIN………………….20
FASTEST MILE FOR YESTERDAY…………………14 SSE AT  10:24 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………13 S   AT  10:25 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE…………..13 E   AT   2:57 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE…………..15 S   AT   7:38 P.M.
AVERAGE WIND SPEED AND DIRECTION………….6.8 SE [163 total miles] ASOS………………….7.6
DAVIS #1………………7.3 SE   [144 deg.] DAVIS #2………………7.5 SE   [147 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE….-0.15
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….4.14  DEPARTURE….+1.31
ASOS…………..4.13
TOTAL PRECIPITATION FOR THE YEAR……….38.56  DEPARTURE….-3.35
ASOS………….39.34

PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 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

10/01  75/56/66/+9/0.00/…/..             28 SW   AERO 28 SW   RMY N/A
10/02  63/49/56/-1/0.02/…/..             20 NW   AERO 21 NW   RMY 20
10/03  65/45/55/-1/0.00/…/..             19 WNW  AERO 19 WNW  RMY 19
10/04  65/45/55/-1/0.00/…/..             17 ESE  AERO 18 ESE  RMY 18
10/05  62/52/57/+1/0.00/…/..             17 ENE  AERO 17 ENE  RMY N/A
10/06  69/51/60/+5/0.00/…/..             28 S    AERO 28 S    RMY 29
10/07  73/50/62/+7/0.14/…/..             76 W    AERO 74 W    RMY 70  TSTM
10/08  61/42/52/-2/0.00/…/..             41 W    AERO 41 W    RMY N/A
10/09  60/37/49/-5/0.00/…/..             25 SSW  AERO 28 SSW  RMY N/A
10/10  75/52/64/+10/0.00/…/..            40 SSW  AERO 40 SSW  RMY 38
10/11  64/47/56/+3/0.00/…/..             32 NNW  AERO 35 NNW  RMY N/A
10/12  52/48/50/-3/T/…/..                28 E    AERO 27 E    RMY N/A
10/13  57/49/53/0/1.74/…/..              32 E    AERO 33 E    RMY N/A
10/14  67/47/57/+5/0.00/…/..             23 WNW  AERO 25 WNW  RMY N/A
10/15  71/50/61/+9/0.00/…/..             43 S    AERO 46 S    RMY 42
10/16  68/48/58/+7/…./…/..             28 S    AERO 30 S    RMY N/A
10/17  56/39/48/-3/…./…/..             35 WNW  AERO 40 WNW  RMY 37
10/18  60/46/53/+2/0.00/…/..             20 ESE  AERO 21 ESE  RMY 20
10/19  61/46/54/+4/0.00/…/..             16 ESE  AERO 16 SSE  RMY N/A

10/20 The low since midnight is 49F, the daily normal low is 41F

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

RECORDS FOR OCTOBER 20
HIGH 78F IN 1965,1984
LOW 24F IN 1972
PRECIP 7.10 INCHES IN 1996 (RECORD FOR MONTH)
SNOWFALL TRACE IN 1934,1943
PEAK GUST 63 MPH W IN 1966

RECORDS FOR OCTOBER 21
HIGH 79F IN 1979
LOW 24F IN 1974
PRECIP 2.39 INCHES IN 1944
SNOWFALL TRACE IN 1895,1907,1940
PEAK GUST 69e MPH S IN 1976

TODAY’S REPORT PREPARED BY: Benjamin Turner