Sunday, July 19, 2020

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

SUNDAY, JULY 19, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

HOT, WITH A SOUTHWESTERLY WIND AND
ABUNDANT AFTERNOON SUNSHINE….

Today was hot and hazy, with a lot of
sunshine around noontime. Visibility was
35 miles at best due to a distant layer
of haze. We had significant warm air
advection after noontime, with winds
reaching 22 miles an hour as a max.
Humidity has luckily dropped off,
with dew points staying in the low
70’s. With that being said, humidity
is at a dryer-than-expected 50%.

The high so far today is 92 degrees. This is
11 degrees above the daily normal high of 81F.
The low since midnight is 69F, which is 6 degrees
above the daily normal low of 63F.

PRELIMINARY STATS FOR JUNE 2020

TEMPERATURE, Deg. F
Avg. Max. 78.0 [+3.0] Avg. Min. 59.1 [+2.0] Mean      68.6 [+2.5] 24-hour corrected mean: 67.5
Max. for month: 90F on the 20th
Min. for month: 42F on the 1st

HEATING DEGREE DAYS
Total heating units:     40 [-33] Total for the season:  5852 [-402] Total for last season: 6254

COOLING DEGREE DAYS
Total cooling units:    152  [+47] Total for the season:   184  [+55] Total for last season:  89

PRECIPITATION, Inches
Total: 7.56 [+3.25] Greatest in 24 hrs: 4.71 inches on the 28th-29th

WIND, mph
Avg. uncorrected wind speed: 9.1 mph
Avg. corrected wind speed:   9.8 mph
Prevailing wind direction:   S [15%] Peak gust and direction:     55 SW on the 6th

SUNSHINE:
Campbell-Stokes card minutes: 15996 minutes of a possible 26376 or 61%
Astronomical total minutes: 16650 minutes of a possible 27422 or 61%

Today’s Observations:

7 A.M.
Weather: Broken cirrus
Temperature: 73F; Dew Point: 67F; Relative Humidity: 80%
Wind: SSW at 7 kts
Sea-level pressure: 29.97 ins. Hg: rising unsteadily
Visibility: 25 miles; hazy
6-hr Max temp: 73F
6-hr Min temp: 69F
24-hr Precip: 0.00 ins.
BHO SA 1155 250 BKN 25 148/73/67/2107/997/ HAZY/ 8/002
50002 10073 20069

10 A.M.
Weather: Scattered cirrus
Temperature: 86F; Dew Point: 70F; Relative Humidity: 60%
Wind: SSW at 10 kts
Sea-level pressure: 29.94 ins. Hg: rising, then falling
Visibility: 30 miles, hazy
3-hr Precip: 0.00 ins.
BHO SA 1455 250 SCT 30 138/86/70/2210/994/ HAZY/ 8/002
56010

1 P.M.
Weather: Scattered cumulus and cirrus
Temperature: 91F; Dew Point: 71F; Relative Humidity: 52%
Wind: SW at 10G20 kts
Sea-level pressure: 29.90 ins. Hg: falling, then more slowly
Visibility: 35 miles, hazy
6-hr Max temp: 92F
6-hr Min temp: 73F
6-hr Precip: 0.00 ins.
BHO SA 1755 40 SCT 250 SCT 35 125/91/71/2110G20/990/ HAZY/
8/202 56013 10092 20073

SUMMARY FOR SATURDAY, JULY 18, 2020

TEMPERATURE (DEGREES F)
MAX…..71   NORMAL…..81
MIN…..57   NORMAL…..63
MEAN….64   NORMAL…..72

DEPARTURE FROM 30-YEAR NORMAL…………….. +6
TOTAL DEPARTURE FOR THE MONTH…………….. +10 [+0.4 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………….. 3  DEPARTURE……. +6
TOTAL COOLING UNITS FOR THE MONTH…………….118  DEPARTURE……. -4
TOTAL COOLING UNITS FOR THE SEASON……………302  DEPARTURE…….+51
TOTAL COOLING UNITS LAST SEASON TO DATE……….270  DEPARTURE…….+32

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..18 W   AT  3:41 P.M.
AERO…………………….17 W   AT  3:43 P.M.
ASOS…………………….20 W   AT  3:41 P.M.
DAVIS……………………19 W   AT  3:40 P.M RMY 19
FASTEST MILE FOR YESTERDAY………………….13 W   AT  4:38 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….15 W   AT  4:39 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………15 W   AT  4:39 P.M.
AVERAGE WIND SPEED AND DIRECTION………….. 7.9 W
ASOS………………….. 7.9
DAVIS…………………. 8.4 WSW [259 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.13
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.06  DEPARTURE……-1.14
ASOS…………..1.06
TOTAL PRECIPITATION FOR THE YEAR……….28.41  DEPARTURE……-0.76
ASOS………….29.07

PRELIMINARY CLIMATE SUMMARY FOR JUNE 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

06/01  64/42/53/-9/T/0.0/724/80            28 WNW  AERO 29 WNW RMY 28
06/02  72/45/59/-3/0.01/0.0/689/76         28 W    AERO 27 W   RMY 28
06/03  79/55/67/+5/0.00/0.0/400/44         29 W    AERO 28 W   RMY 26
06/04  87/62/75/+12/0.00/0.0/673/74        26 W    AERO 25 S   RMY N/A
06/05  80/65/73/+10/0.14/0.0/300/33        28 SSW  AERO 28 SSW RMY N/A TSTM
06/06  86/57/72/+9/1.14/0.0/301/33         55 SW   AERO 59 SW  RMY 59  TSTM
06/07  68/54/61/-3/0.00/0.0/255/28         24 NW   AERO 24 NW  RMY N/A
06/08  77/51/64/0/0.00/0.0/866/95          25 W    AERO 24 W   RMY 25
06/09  77/60/69/+5/T/0.0/110/12            23 E    AERO 21 E   RMY N/A
06/10  70/58/64/-1/0.00/0.0/658/72         25 E    AERO 24 E   RMY N/A
06/11  71/64/68/+3/0.62/0.0/165/18         40 S    AERO 40 S   RMY 42
06/12  82/63/73/+8/0.00/0.0/705/77         26 W    AERO 25 W   RMY 27
06/13  71/53/62/-3/0.00/0.0/669/73         21 WNW  AERO 20 WNW RMY N/A
06/14  67/49/58/-8/0.00/0.0/852/93         21 E    AERO 21 ENE RMY 21
06/15  67/53/60/-6/5/0.00/0.0/696/76       21 NE   AERO 16 ENE RMY 20
06/16  73/54/64/-2/0.00/0.0/889/97         18 E    AERO 18 E   RMY 18
06/17  78/57/68/+1/0.00/0.0/889/97         20 S    AERO 20 S   RMY 20
06/18  86/59/73/+6/0.00/0.0/715/78         22 S    AERO 22 SSW RMY 22
06/19  86/66/76/+9/0.00/0.0/789/86         22 S    AERO 22 S   RMY 21
06/20  90/65/78/+10/0.00/0.0/834/91        22 S    AERO 21 S   RMY 21
06/21  90/66/78/+10/0.83/0.0/514/56        33 ESE  AERO 35 ESE RMY 33  TSTM
06/22  77/65/71/+3/T/0.0/761/83            15 E    AERO 17 S   RMY 14
06/23  85/65/75/+7/0.00/0.0/431/47         27 S    AERO 24 S   RMY 26
06/24  84/66/75/+6/0.00/0.0/348/38         25 S    AERO 24 S   RMY 25
06/25  84/63/74/+5/0.00/0.0/806/88         29 W    AERO 29 W   RMY 29
06/26  83/65/74/+5/0.02/0.0/769/84         25 S    AERO 25 S   RMY 27
06/27  82/65/74/+5/0.05/0.0/330/36         21 S    AERO 20 S   RMY 20
06/28  84/62/73/+3/3.27/0.0/421/46         35 W    AERO 33 N   RMY 37  TSTM
06/29  71/61/66/-4/1.46/0.0/064/07         18 NE   AERO 18 NE  RMY 18  TSTM
06/30  68/62/65/-5/0.02/0.0/027/03         14 ENE  AERO 14 ENE RMY 13  TSTM

Record rainfall on the 28th of 3.27″. Old record 2.09″ in 1938

PRELIMINARY CLIMATE SUMMARY FOR JULY 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

07/01  76/63/70/0/0.00/228/25              16 E    AERO 14 E    RMY 14  TSTM
07/02  86/61/74/4/0.00/803/88              30 WSW  AERO 25 WSW  RMY 33
07/03  73/60/67/-4/0.00/091/10             30 NE   AERO 28 NE   RMY 30
07/04  79/60/70/-1/0.00/565/62             16 S    AERO 16 S    RMY 16
07/05  83/63/73/+2/0.54/373/41             24 NW   AERO 30 NW   RMY 26  TSTM
07/06  73/60/67/-4/0.00/…/..             20 ENE  AERO 16 NNE  RMY 18
07/07  78/60/69/-2/0.00/…/..             25 S    AERO 25 S    RMY 26
07/08  83/64/74/+2/0.00/…/..             32 SSW  AERO 32 SSW  RMY 32
07/09  89/70/80/+8/0.00/…/.              24 S    AERO 23 S    RMY 22
07/10  83/70/77/+5/0.05/…/..             30 SSE  AERO 32 SSE  RMY N/A
07/11  85/70/78/+6/0.00/…/..             39 S    AERO 39 S    RMY 38
07/12  86/70/78/+6/0.00/…/..             28 WSW  AERO 28 WSW  RMY 29
07/13  82/69/76/+4/0.23/…/..             30 SSE  AERO 31 SSE  RMY 30  TSTM
07/14  78/63/71/-1/0.00/…/..             26 ENE  AERO 25 ENE  RMY 26
07/15  72/59/66/-6/0.00/…/..             21 NE   AERO 21 NE   RMY N/A
07/16  73/57/65/-7/0.00/…/..             21 E    AERO 21 E    RMY 19
07/17  71/57/64/-8/0.19/…/..             24 SSW  AERO 24 SSW  RMY 25
07/18  89/66/78/+6/0.00/…/..             18 W    AERO 17 W    RMY 19

07/19 The low since midnight is 69F, the daily normal low is 63F

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

RECORDS FOR JULY 19
HIGH 96F IN 1977, 1991
LOW 50F IN 1890
PRECIP 1.10 INS IN 1951
WIND 63 MPH SSW IN 1982

RECORDS FOR JULY 20
HIGH 99F IN 1991
LOW 47F IN 1890
PRECIP 1.64 INS IN 1938
WIND 56e MPH SSW IN 1943

TODAY’S REPORT PREPARED BY: Benjamin Turner