Monday, July 20, 2020

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

MONDAY, JULY 20, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

ANOTHER HOT AND HAZY DAY, BUT SLIGHTLY
COOLER DUE TO A STRONGER BREEZE AND
MORNING CLOUD COVER….

Skies were overcast this morning, with
the sun breaking out around noontime.
A consistent westerly breeze is coming
in, at a speed around 18 mph. The max
gust is 23 mph. Visibility was limited
to 30 miles at most due to haze. Today
is humid, with dew points in the low
70’s. Despite a relative humidity of
60%, the air still has quite the water
content.

The high so far today is 88 degrees. This is
7 degrees above the daily normal high of 81F.
The low since midnight is 72F, which is 9 degrees
above the daily normal low of 63F.

Today’s Observations:

7 A.M.
Weather: Overcast altostratus
Temperature: 76F; Dew Point: 71F; Relative Humidity: 85%
Wind: SSW at 10G16 kts
Sea-level pressure: 29.85 ins. Hg: rising steadily
Visibility: 20 miles; hazy
6-hr Max temp: 76F
6-hr Min temp: 72F
24-hr Precip: 0.00 ins.
BHO SA 1155 120 OVC 20 107/76/71/2110G16/985/ HAZY/ 8/07/
53006 10076 20072

10 A.M.
Weather: Broken altostratus
Temperature: 80F; Dew Point: 74F; Relative Humidity: 82%
Wind: SW at 9 kts
Sea-level pressure: 29.84 ins. Hg: rising, then falling
Visibility: 30 miles, hazy
3-hr Precip: Trace
BHO SA 1455 120 BKN 30 103/80/74/2309/984/ HAZY/ 8/070 600//
58004

1 P.M.
Weather: Scattered cumulus, broken altostratus and cirrus
Temperature: 86F; Dew Point: 74F; Relative Humidity: 67%
Wind: W at 10 kts
Sea-level pressure: 29.81 ins. Hg: falling, then more slowly
Visibility: 30 miles, hazy
6-hr Max temp: 88F
6-hr Min temp: 76F
6-hr Precip: Trace
BHO SA 1755 40 SCT 120 BKN 250 BKN 30 093/86/74/2610/981/ HAZY/
8/278 600// 58010 10088 20076

SUMMARY FOR SUNDAY, JULY 19, 2020

TEMPERATURE (DEGREES F)
MAX…..92   NORMAL…..81
MIN…..69   NORMAL…..63
MEAN….81   NORMAL…..72

DEPARTURE FROM 30-YEAR NORMAL…………….. +9
TOTAL DEPARTURE FOR THE MONTH…………….. +19 [+0.8 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………..16  DEPARTURE……. +9
TOTAL COOLING UNITS FOR THE MONTH…………….134  DEPARTURE……. +4
TOTAL COOLING UNITS FOR THE SEASON……………318  DEPARTURE…….+59
TOTAL COOLING UNITS LAST SEASON TO DATE……….280  DEPARTURE…….+38

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..28 S   AT  3:25 P.M.
AERO…………………….28 S   AT  3:25 P.M.
ASOS…………………….27 S   AT  3:26 P.M.
DAVIS……………………29 S   AT  9:35 P.M RMY 26
FASTEST MILE FOR YESTERDAY………………….19 S   AT  9:34 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….20 S   AT  9:40 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………19 S   AT  9:35 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..12.3 S
ASOS…………………..12.7
DAVIS………………….11.6 SSW [208 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……-1.27
ASOS…………..1.06
TOTAL PRECIPITATION FOR THE YEAR……….28.41  DEPARTURE……-0.89
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 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 20
HIGH 99F IN 1991
LOW 47F IN 1890
PRECIP 1.64 INS IN 1938
WIND 56e MPH SSW IN 1943

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

TODAY’S REPORT PREPARED BY: Benjamin Turner