Sunday, July 4, 2021
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
SUNDAY, JULY 4, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0413E
SUNSET: 1924E
AN OVERCAST AND COOL JULY 4TH….
Today we’ve again experienced lower than normal temperatures,
only reaching the low to mid 60’s. Overnight rainfall totaled
1.91 inches, with an additional trace falling between 7 A.M.
and 1 P.M. Wind is northwesterly at an average speed of 10 mph
and a max gust of 16 mph. Despite some fog this morning, the
visibility went up to 80 miles!
Following the thunderstorms and rainfall last night, we are
back on track in regard to rain totals. Monthly rainfall is
4.35 inches within the first 4 days of the month, boasting
a 4-inch surplus for rainfall currently. The yearly rain
total is back up to average, now exceeding the average
rain total by a 1/2 inch at this time of year.
The high temperature for yesterday was 56F, which barely misses
the low maximum record for the calendar date. However, it tied
As the second coldest daily maximum temperature ever observed
In June!
BHO Coldest July Daily Maximum Temperature, deg F (1885-2021):
1) 55 on 3 July 1914
2) 56 on 4 July 1978
56 on 3 July 1921
4) 57 on 6 July 1918
57 on 6 July 1956
57 on 4 July 1992
7) 58 on 2 July 1914
58 on 11 July 1917
58 on 5 July 1933
-Special thanks to Chief Scientist Mike Iacono!
The high so far today is 65F, 16 degrees below the daily average
of 81F. The low so far today is 54F, 9 degrees below the daily
average of 63F.
PRELIMINARY STATS FOR JUNE 2021
TEMPERATURE, Deg. F
Avg. Max. 80.9 [+5.9]Avg. Min. 60.4 [+3.3]Mean 70.9 [+4.6]24-hour corrected mean: 70.0
Max. for month: 95F on the 29th
Min. for month: 50F on the 1st
HEATING DEGREE DAYS
Total heating units: 19 [-54]Total for the season: 5597 [-725]Total for last season: 5852
COOLING DEGREE DAYS
Total cooling units: 187 [+75]Total for the season: 197 [+82]Total for last season: 184
PRECIPITATION, Inches
Total: 2.72 [-1.59]Greatest in 24 hrs: 0.68 inches on the 22nd
WIND, mph
Avg. uncorrected wind speed: 10.4 mph
Avg. corrected wind speed: 10.6 mph
Prevailing wind direction: SSW [22%]Peak gust and direction: 51 NW on the 30th
SUNSHINE:
Campbell-Stokes card minutes: N/A
Astronomical total minutes: N/A
Today’s Observations:
7 A.M.
Weather: Overcast stratus
Temperature: 55F; Dew Point: 55F; Relative Humidity: 100%
Wind: NNW @ 5G12 kts
Sea-level pressure: 29.86 in. Hg; rising steadily
Visibility: 1 mile with fog, except 15 miles E-SE
6-hr Max temp: 55F
6-hr Min temp: 54F
24-hr Precip: 1.91 ins.
BHO SA 1155 20 OVC 1F 113/55/55/3405G12/986/ VSBY E-SE 15 MI/ 8/6//
53012 10055 20054
10 A.M.
Weather: Very light rain, overcast stratocumulus
Temperature: 57F; Dew Point: 56F; Relative Humidity: 95%
Wind: WNW @ 6G11 kts
Sea-level pressure: 29.88 in Hg; rising steadily
Visibility: 60 miles, except 30 miles to the west due
to a distant rain shower
3-hr Precip: Trace
BHO SA 1455 30 OVC 60R- 121/57/56/3006G11/988/ VSBY W 30 MI VIRGA
W-NW R-B55 PCPN VRY LGT / 8/8// 600// 53008
1 P.M.
Weather: Overcast stratocumulus
Temperature: 64F, Dew point: 55F; Relative Humidity: 73%
Wind: E @ 10 kts
Sea-level pressure: 29.89 in Hg; rising slowly
Visibility: 80 miles
6-hr Max temp: 65F
6-hr Min temp: 55F
6-hr Precip: Trace
BHO SA 1755 40 OVC 80 124/64/55/0810/989/ VIRGA DSNT OFFSHR/ 8/8// 600//
52003 10065 20055
SUMMARY FOR SATURDAY, JULY 3, 2021
TEMPERATURE (DEGREES F)
MAX…….56 NORMAL…..81
MIN…….54 NORMAL…..63
MEAN……55 NORMAL…..72
DEPARTURE FROM 30-YEAR (1991-2020) NORMAL………-17
TOTAL DEPARTURE FOR THE MONTH…………………-26 [-8.5 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON: JUL 2021 THRU JUN 2022)
TOTAL HEATING UNITS FOR YESTERDAY……………10 DEPARTURE…….+10
TOTAL HEATING UNITS FOR THE MONTH……………15 DEPARTURE…….+14
TOTAL HEATING UNITS FOR THE SEASON…………..14 DEPARTURE…….+14
TOTAL HEATING UNITS LAST SEASON TO DATE……….0 DEPARTURE…….+15
COOLING DEGREE DAYS (SEASON: JAN 2021 THRU DEC 2021)
TOTAL COOLING UNITS FOR YESTERDAY…………….0 DEPARTURE…….-7
TOTAL COOLING UNITS FOR THE MONTH…………….8 DEPARTURE……-12
TOTAL COOLING UNITS FOR THE SEASON………….198 DEPARTURE……+75
TOTAL COOLING UNITS LAST SEASON TO DATE……..200 DEPARTURE……+34
PEAK WIND GUST (MPH):
420C/Official…………..41 NE @ 6:53 P.M.
AEROVANE (south tower)…..44 NE @ 6:31 P.M.
ASOS…………OUT OF SERVICE D/T RENOVATIONS
VECTOR #1………………50 @ 6:52 P.M.
VECTOR #2 (south tower)….46 @ 6:51 P.M.
DAVIS #1……………….40 E @ 6:52 P.M.
DAVIS #2 (south tower)…..40 NE @ 6:54 P.M.
RMY……………………45 @ 6:50 P.M.
MERLIN…………………39
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………27 NE @ 6:53 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……..OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..27 @ 6:52 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………29 ENE @ 6:52 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………29 ENE @ 6:53 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..26 E @ 6:52 P.M.
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……12.1 NE [291 total miles] ASOS…………………OUT OF SERVICE D/T RENOVATIONS
VECTOR #1…………….12.0
DAVIS #1……………..12.5 NE
DAVIS #2……………..12.3 NE
RMY………………….11.5 ENE
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….1.91 DEPARTURE….+1.80
TOTAL PRECIPITATION FOR THE MONTH………….4.35 DEPARTURE….+4.01
TOTAL PRECIPITATION FOR THE YEAR………….27.73 DEPARTURE….+0.42
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 74/50/62/0/0.00/425/47 20 WSW AERO 24 WSW RMY 22
06/02 80/55/68/+6/0.00/553/61 28 S AERO 25 S RMY 28
06/03 73/56/65/+3/0.01/073/08 29 SSW AERO 29 SSW RMY 29
06/04 77/61/69/+6/0.02/054/06 23 SW AERO 25 WSW RMY 25 TSTM
06/05 87/60/74/+11/0.00/801/88 32 SSW AERO 37 SSW RMY 35
06/06 91/69/80/+17/0.00/819/90 30 WSW AERO 31 WSW RMY 32
06/07 92/69/81/+17/0.00/838/92 31 SSW AERO 35 SSW RMY 34
06/08 92/69/81/+17/0.06/456/50 24 WSW AERO 25 WSW RMY 27 TSTM
06/09 88/70/79/+15/0.02/530/58 21 N AERO 23 NNW RMY 23
06/10 70/53/62/-3/0.00/795/87 28 NE AERO 28 NE RMY 28
06/11 70/51/61/-4/0.13/411/45 21 SSE AERO 22 SSE RMY 22
06/12 72/53/63/-2/0.43/430/47 20 WSW AERO 18 WSW RMY 20
06/13 82/56/69/+4/0.00/860/94 26 SSW AERO 29 SSW RMY 29
06/14 65/56/61/-5/0.63/027/03 28 S AERO 30 SSE RMY 29
06/15 77/61/69/+3/T/357/39 18 NE AERO 20 NE RMY 18 TSTM
06/16 73/56/65/-1/0.00/769/84 27 NNW AERO 31 NNW RMY 27
06/17 77/52/65/-2/0.00/880/96 21 WNW AERO 21 NW RMY 23
06/18 82/56/69/+2/T/789/86 26 WSW AERO 28 WSW RMY 30
06/19 86/63/75/+8/0.09/504/55 30 SW AERO 32 SW RMY 32
06/20 85/63/74/+6/0.00/816/89 24 S AERO 25 SSW RMY 25
06/21 83/65/74/+6/0.00/…/.. 37 SSW AERO 39 SSW RMY 39
06/22 84/58/71/+3/0.68/…/.. 30 NW AERO 31 NW RMY 31 TSTM
06/23 73/52/63/-5/0.00/…/.. 25 NW AERO 24 NW RMY 26
06/24 76/58/67/-2/T/…/.. 25 SE AERO 24 SE RMY 25
06/25 71/57/64/-5/0.11/…/.. 23 S AERO 23 S RMY 23
06/26 81/61/71/+2/0.00/…/.. 36 SSW AERO 37 SSW RMY 38
06/27 85/70/78/+9/0.00/…/.. 38 SW AERO 39 SW RMY 42
06/28 93/70/82/+12/0.00/…/.. 28 SW AERO 28 SW RMY 28
06/29 95/73/84/+14/T/…/.. 26 W AERO 30 W RMY 27 TSTM
06/30 94/69/82/+12/0.54/…/.. 51 NW AERO 53 NW RMY 56 TSTM
RECORDS FOR JUNE:
JUNE 7: Record high minimum temperature of 69F,
Surpasses previous record of 66F set in 1922 and 1953
JUNE 29: Record high maximum temperature of 95F,
Surpasses previous record of 94F set in 1933
JUNE 29: Record high minimum temperature of 73F,
Surpasses previous record of 71F set in 1999
JUNE 30: Record high maximum temperature of 94F,
Ties previous record of 94F set in 1964
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 80/65/73/+2/0.74/…/.. 22 W AERO 20 WSW RMY 21
07/02 65/55/60/-11/1.52/…/.. 37 NE AERO 36 NE RMY 39
07/03 56/54/55/-17/…./…/.. 41 NE AERO 44 NE RMY 45
07/04 The low since midnight is 54F, 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 4
HIGH 99F IN 1911
LOW 48F IN 1914
PRECIP 2.48 IN 2014
PEAK GUST 50e MPH WNW IN 1949
RECORDS FOR JULY 5
HIGH 98F IN 1911
LOW 48F IN 1920, 1927 & 1979
PRECIP 1.45 INS IN 1922
PEAK GUST 49e N IN 1944
TODAY’S REPORT PREPARED BY: Benjamin Turner
