Wednesday, July 7, 2021
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
WEDNESDAY, JULY 7, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0415E
SUNSET: 1923E
AFTERNOON THUNDERSTORMS ARE THE MOST NOTABLE AS
THE DAY WAS VERY SIMILAR TO THE ONE BEFORE….
We measured only 0.24 inches of rainfall from last night’s
thunderstorms. That is a surprise considering a lightning
bolt knocked out the main electricity line to the observatory
yesterday evening. Today was very much like the one before
regarding temperature and humidity.
Visibility has been poor today thanks to haziness. We’ve
only been able to see 15-20 miles.
The wind has been generally out of the southwest, gusting
at times to only 15-20 mph.
Storms have begun to move in from the west, with lightning bolts
being seen through the haze at around 5:39 P.M. EST.
The high so far today is 87F, 6 degrees above the daily average
of 81F. The low so far today is 66F, 3 degrees above 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 70.7 [+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: 197 [+92]Total for the season: 226 [+97]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: 10.9 mph
Prevailing wind direction: SSW [22%]Peak gust and direction: 51 NW on the 30th
SUNSHINE:
Campbell-Stokes card minutes: 16230 minutes of a possible 26376 or 62%
Astronomical total minutes: 16866 minutes of a possible 27415 or 62%
Today’s Observations:
7 A.M.
Weather: Scattered cirrus
Temperature: 71F; Dew Point: 67F; Relative Humidity: 87%
Wind: W @ 11G15 kts
Sea-level pressure: 29.93 in. Hg; rising steadily
Visibility: 20 miles, hazy
6-hr Max temp: 71F
6-hr Min temp: 66F
24-hr Precip: 0.24 ins.
BHO SA 1155 250 SCT 20 137/71/67/2711G15/993/ HAZY/ 8/001
70024 53009 10071 20066
10 A.M.
Weather: Scattered cirrus, few cumulus
Temperature: 81F; Dew Point: 70F; Relative Humidity: 69%
Wind: SSW @ 8G10 kts
Sea-level pressure: 29.94 in Hg; falling then rising
Visibility: 20 miles, hazy
3-hr Precip: 0.00 ins.
BHO SA 1455 250 SCT 20 141/81/70/2008G10/994/ FEW CU ALQDS
HAZY/ 8/101 51004
1 P.M.
Weather: Scattered building cumulus, broken cirrus
Temperature: 85F, Dew point: 71F; Relative Humidity: 63%
Wind: WNW @ 7G12 kts
Sea-level pressure: 29.92 in Hg; falling steadily
Visibility: 20 miles, hazy
6-hr Max temp: 87F
6-hr Min temp: 71F
6-hr Precip: 0.00 ins.
BHO SA 1755 50 SCT 250 BKN 20 135/85/71/2907G12/992/ HAZY/ 8/201
58006 10087 20071
SUMMARY FOR TUESDAY, JULY 6, 2021
TEMPERATURE (DEGREES F)
MAX…….87 NORMAL…..81
MIN…….66 NORMAL…..63
MEAN……77 NORMAL…..72
DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……… +5
TOTAL DEPARTURE FOR THE MONTH…………………-41 [-7.0 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON: JUL 2021 THRU JUN 2022)
TOTAL HEATING UNITS FOR YESTERDAY…………….0 DEPARTURE……. 0
TOTAL HEATING UNITS FOR THE MONTH……………21 DEPARTURE…….+19
TOTAL HEATING UNITS FOR THE SEASON…………..21 DEPARTURE…….+19
TOTAL HEATING UNITS LAST SEASON TO DATE……….0 DEPARTURE…….+21
COOLING DEGREE DAYS (SEASON: JAN 2021 THRU DEC 2021)
TOTAL COOLING UNITS FOR YESTERDAY……………12 DEPARTURE…….+5
TOTAL COOLING UNITS FOR THE MONTH……………20 DEPARTURE……-22
TOTAL COOLING UNITS FOR THE SEASON………….246 DEPARTURE……+65
TOTAL COOLING UNITS LAST SEASON TO DATE……..215 DEPARTURE……+31
PEAK WIND GUST (MPH):
420C/Official…………..37 W @ 5:25 P.M.
AEROVANE (south tower)…..48 W @ 5:23 P.M.
ASOS…………OUT OF SERVICE D/T RENOVATIONS
VECTOR #1………………37 @ 5:25 P.M.
VECTOR #2 (south tower)….50 @ 5:24 P.M.
DAVIS #1……………….37 WSW @ 5:25 P.M.
DAVIS #2 (south tower)…..41 W @ 5:24 P.M.
RMY……………………38 @ 5:24 P.M.
MERLIN…………………37
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………25 W @ 5:24 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……..OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..27 @ 5:30 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………28 W @ 5:30 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………27 W @ 5:25 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..27 W @ 5:30 P.M.
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……13.9 SW [334 total miles] ASOS…………………OUT OF SERVICE D/T RENOVATIONS
VECTOR #1…………….14.2
DAVIS #1……………..14.2 WSW
DAVIS #2……………..14.4 SW
RMY………………….13.6 SW
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.24 DEPARTURE….+0.13
TOTAL PRECIPITATION FOR THE MONTH………….4.64 DEPARTURE….+3.97
TOTAL PRECIPITATION FOR THE YEAR………….28.02 DEPARTURE….+0.38
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/+6/0.00/514/56 37 SSW AERO 39 SSW RMY 39
06/22 84/58/71/+3/0.68/229/25 30 NW AERO 31 NW RMY 31 TSTM
06/23 73/52/63/-5/0.00/807/88 25 NW AERO 24 NW RMY 26
06/24 76/58/67/-2/T/899/98 25 SE AERO 24 SE RMY 25
06/25 71/57/64/-5/0.11/046/05 23 S AERO 23 S RMY 23
06/26 81/61/71/+2/0.00/376/41 36 SSW AERO 37 SSW RMY 38
06/27 85/70/78/+9/0.00/476/52 38 SW AERO 39 SW RMY 42
06/28 93/70/82/+12/0.00/851/93 28 SW AERO 28 SW RMY 28
06/29 95/73/84/+14/T/750/82 26 W AERO 30 W RMY 27 TSTM
06/30 94/69/82/+12/0.54/731/80 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/-11/1.49/…/.. 37 NE AERO 36 NE RMY 39
07/03 56/54/55/-17/1.98/…/.. 41 NE AERO 44 NE RMY 45
07/04 66/54/60/-12/0.16/…/.. 26 ENE AERO 23 ENE RMY 26
07/05 74/53/64/-8/0.01/…/.. 26 SSW AERO 28 SSW RMY 27
07/06 87/66/77/+5/0.24/…/.. 37 W AERO 48 W RMY 38 TSTM
07/07 The low since midnight is 66F, the daily normal low is 63F
RECORDS FOR JULY:
JULY 2: Record daily precipitation of 1.49″,
Surpasses previous record of 1.42″ set in 1986
JULY 3: Record daily precipitation of 1.98″,
Surpasses previous record of 1.36″ set in 1985
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR JULY 7
HIGH 97F IN 1908,1993
LOW 48F IN 1902
PRECIP 2.11 INS IN 1966
PEAK GUST 55 MPH NW IN 1989
RECORDS FOR JULY 8
HIGH 95F IN 1981
LOW 50F IN 1919
PRECIP 1.74 INS IN 1916
PEAK GUST 46e SSW IN 1941
TODAY’S REPORT PREPARED BY: Benjamin Turner
