Tuesday, July 21, 2020

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

TUESDAY, JULY 21, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

LESS HUMIDITY, WITH BETTER VISIBILITY
AND PARTIAL CLOUD COVER….

Today felt on the cooler side in
comparison with days prior, with
dew points staying in the low 60s.
Wind was westerly at an average of
10 mph. Visibility reached almost
65 miles in the middle of the day,
falling back to 60 miles by the
1 P.M. observation. Conditions
were partly cloudy, consisting
of mostly fair weather cumulus and
a layer of patchy altocumulus above
it. Skies have cleared out in the
late afternoon hours.

The high so far today is 87 degrees.
This is 6 degrees above the daily
normal high of 81F. The low since
midnight is 68F, which is 5 degrees
above the daily normal low of 63F.

Today’s Observations:

7 A.M.
Weather: Few cirrus
Temperature: 74F; Dew Point: 63F; Relative Humidity: 69%
Wind: WNW at 7 kts
Sea-level pressure: 29.99 ins. Hg: rising steadily
Visibility: 45 miles
6-hr Max temp: 74F
6-hr Min temp: 68F
24-hr Precip: Trace
BHO SA 1155 CLR 45 156/74/63/3007/999/ FEW CI ALQDS/
8/002 51015 10074 20068

10 A.M.
Weather: Scattered cumulus, broken altocumulus
Temperature: 83F; Dew Point: 65F; Relative Humidity: 55%
Wind: WNW at 7 kts
Sea-level pressure: 30.00 ins. Hg: rising, then falling
Visibility: 60 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 50 SCT 170 BKN 60 160/83/65/2907/000/ 8/150
53004

1 P.M.
Weather: Scattered cumulus and broken altocumulus
Temperature: 83F; Dew Point: 65F; Relative Humidity: 55%
Wind: W at 9G22 kts
Sea-level pressure: 30.00 ins. Hg: falling, then more slowly
Visibility: 60 miles
6-hr Max temp: 87F
6-hr Min temp: 74F
6-hr Precip: 0.00 ins.
BHO SA 1755 50 SCT 170 BKN 60 159/83/65/2809G22/000/ 8/150
55001 10087 20074

SUMMARY FOR MONDAY, JULY 20, 2020

TEMPERATURE (DEGREES F)
MAX…..92   NORMAL…..81
MIN…..72   NORMAL…..63
MEAN….82   NORMAL…..72

DEPARTURE FROM 30-YEAR NORMAL…………….. +10
TOTAL DEPARTURE FOR THE MONTH…………….. +29 [+1.3 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………..17  DEPARTURE…….+10
TOTAL COOLING UNITS FOR THE MONTH…………….151  DEPARTURE…….+14
TOTAL COOLING UNITS FOR THE SEASON……………335  DEPARTURE…….+69
TOTAL COOLING UNITS LAST SEASON TO DATE……….299  DEPARTURE…….+36

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..25 SSW AT  5:17 A.M.
AERO…………………….25 SSW AT  5:17 A.M.
ASOS…………………….25 SW  AT  5:17 A.M.
DAVIS……………………25 SW  AT  5:16 A.M RMY N/A
FASTEST MILE FOR YESTERDAY………………….19 SSW AT  5:16 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….21 SSW AT  5:17 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………20 SSW AT  5:17 A.M.
AVERAGE WIND SPEED AND DIRECTION…………..12.1 SW
ASOS…………………..11.8
DAVIS………………….12.0 WSW [248 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…Trace  DEPARTURE……-0.13
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.06  DEPARTURE……-1.40
ASOS…………..1.06
TOTAL PRECIPITATION FOR THE YEAR……….28.41  DEPARTURE……-1.02
ASOS………….29.07

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  92/69/81/+9/0.00/…/..             28 S    AERO 28 S    RMY 26
07/20  91/72/82/+10/T/…/..               25 SSW  AERO 25 SSW  RMY N/A

07/21 The low since midnight is 72F, 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 21
HIGH 100F IN 1977 [RECORD FOR MONTH] LOW 48F IN 1890
PRECIP 2.09 INS IN 1938
PEAK GUST 60e MPH WNW IN 1977

RECORDS FOR JULY 22
HIGH 99F IN 1926, 2011
LOW 52F IN 1890
PRECIP 1.73 INS IN 1900
PEAK GUST 55 MPH IN 1983

TODAY’S REPORT PREPARED BY: Benjamin Turner