Thursday, July 29, 2021

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

THURSDAY, JULY 29, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0434E
SUNSET:  1907E

EVEN COOLER WITH AN ALMOST CHILLY BREEZE
IN THE AFTERNOON….

We observed mostly cloudy skies throughout the day,
with some distant rain being seen around 1 P.M.
Conditions were actually on the chilly side today,
with a stiff southerly wind up to 35 mph. Pressure
is on a steady drop, signifying a frontal passage.

The high so far today is 77F, 5 degrees below the daily
normal maximum of 82F. The low so far today is 61F, which
is 3 degrees below the daily normal minimum of 64F.

———————————————–

Today’s Observations:

7 A.M.
Weather: Scattered cumulus, broken altocumulus
Temperature: 65F; Dew Point: 63F; Relative Humidity: 92%
Wind: SSW @ 8 kts
Sea-level pressure: 30.06 in. Hg; steady then rising
Visibility: 25 miles, thin fog
6-hr Max temp: 65F
6-hr Min temp: 61F
24-hr Precip: 0.07 ins.
BHO SA 1155 30 SCT E65 BKN 25 179/65/63/2108/006/ THN F
ALQDS/ 8/870 51007 70007 10065 20061

10 A.M.
Weather: Broken cumulus and stratocumulus
Temperature: 73F; Dew Point: 63F; Relative Humidity: 72%
Wind: SSW @ 11 kts
Sea-level pressure: 30.03 in Hg; falling steadily
Visibility: 45 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 35 BKN 45 BKN 45 169/73/63/2011/003/ 8/800 58010


1 P.M.
Weather: Broken cumulus and stratocumulus, broken altostratus,
Overcast cirrostratus
Temperature: 71F, Dew point: 59F; Relative Humidity: 66%
Wind: S @ 18G24 kts, peak of 32 mph at 12:18 P.M.  
Sea-level pressure: 29.96 in Hg; falling then more rapidly
Visibility: 35 miles
6-hr Max temp: 77F
6-hr Min temp: 65F
6-hr Precip: 0.00 ins.
BHO SA 1755 40 SCT 50 BKN 90 BKN 200 OVC 35 145/71/59/1918G24/996/
VIRGA ESE-SE AND NW-NNE PK WND 1928/18/ 8/878 58024 10077 20065


SUMMARY FOR WEDNESDAY, JULY 28, 2021

TEMPERATURE (DEGREES F)
MAX…….72     NORMAL…..82
MIN…….61     NORMAL…..64
MEAN……67     NORMAL…..73

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……….-6
TOTAL DEPARTURE FOR THE MONTH…………………-94 [-3.6 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……………26  DEPARTURE…….+20
TOTAL HEATING UNITS FOR THE SEASON…………..26  DEPARTURE…….+20
TOTAL HEATING UNITS LAST SEASON TO DATE……….1  DEPARTURE…….+25

COOLING DEGREE DAYS (SEASON: JAN 2021 THRU DEC 2021)
TOTAL COOLING UNITS FOR YESTERDAY…………….2  DEPARTURE……..-6
TOTAL COOLING UNITS FOR THE MONTH…………..146  DEPARTURE…….-77
TOTAL COOLING UNITS FOR THE SEASON………….372  DEPARTURE…….+10
TOTAL COOLING UNITS LAST SEASON TO DATE……..446  DEPARTURE…….-74

PEAK WIND GUST (MPH):
                     Official……………….18 NNE @  8:21 A.M.
                     AEROVANE (south tower)…..18 NNE @  8:22 A.M.
                     VECTOR #2 (south tower)….19     @  8:21 A.M.
                     DAVIS #2 (south tower)…..18 ENE @  8:22 A.M.
                     ASOS………..OUT OF SERVICE D/T RENOVATIONS
                     VECTOR #1……OUT OF SERVICE D/T RENOVATIONS
                     DAVIS #1…….OUT OF SERVICE D/T RENOVATIONS
                     RMY…………OUT OF SERVICE D/T RENOVATIONS  
                     MERLIN………OUT OF SERVICE D/T RENOVATIONS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………12 NNE @  8:25 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..13     @  8:21 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………13 NE  @  8:21 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE…….OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE…OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE..OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE RMY AVERAGE……..OUT OF SERVICE D/T RENOVATIONS

AVERAGE WIND SPEED AND DIRECTION:
                     CONTACTING/OFFICIAL…… 6.5 NE  [156 total miles]                     VECTOR #2……………. 7.4
                     DAVIS #2…………….. 7.1 ENE
                     RMY……………..OUT OF SERVICE D/T RENOVATIONS
                     ASOS…………….OUT OF SERVICE D/T RENOVATIONS
                     VECTOR #1………..OUT OF SERVICE D/T RENOVATIONS
                     DAVIS #1…………OUT OF SERVICE D/T RENOVATIONS   

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.07  DEPARTURE….-0.04
TOTAL PRECIPITATION FOR THE MONTH…………11.41  DEPARTURE….+8.30
TOTAL PRECIPITATION FOR THE YEAR………….34.79  DEPARTURE….+4.71


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/+2/0.74/155/17           22 W   AERO 20 WSW  RMY 21
07/02   65/55/60/-11/1.49/000/00          37 NE  AERO 36 NE   RMY 39
07/03   56/54/55/-17/1.98/000/00          41 NE  AERO 44 NE   RMY 45 TSTM
07/04   66/54/60/-12/0.16/191/21          26 ENE AERO 23 ENE  RMY 26
07/05   74/53/64/-8/0.01/546/60           26 SSW AERO 28 SSW  RMY 27
07/06   87/66/77/+5/0.26/255/28           37 W   AERO 48 W    RMY 38 TSTM
07/07   88/88/77/+5/0.77/699/77           63 NW  AERO 75 NW   RMY 70 TSTM
07/08   67/59/63/-9/0.38/109/12           46 W   AERO 46 W    RMY 51 TSTM
07/09   73/62/68/-5/3.02/163/18           40 WNW AERO 44 WNW  RMY 43
07/10   71/63/67/-6/0.07/109/12           23 NE  AERO 21 NNE  RMY 22
07/11   81/61/71/-2/T/325/36              21 SW  AERO 19 S    RMY N/A
07/12   67/61/64/-9/1.01/000/00           31 ENE AERO 31 ENE  RMY N/A
07/13   66/60/63/-10/0.02/000/00          19 E   AERO 18 E    RMY N/A
07/14   80/62/71/-2/0.01/216/24           19 S   AERO 18 S    RMY N/A
07/15   88/67/78/+5/0.00/844/94           19 WSW AERO 18 SSW  RMY N/A
07/16   90/70/80/+7/0.04/609/68           36 NNW AERO 39 NNW  RMY N/A TSTM
07/17   78/64/71/-2/0.34/394/44           26 ENE AERO 25 ENE  RMY N/A TSTM
07/18   74/63/69/-4/0.15/000/00           22 NE  AERO 22 NE   RMY N/A TSTM
07/19   71/63/67/-6/0.07/027/03           17 ENE AERO 17 ENE  RMY N/A
07/20   83/64/74/+1/0.00/730/82           23 NW  AERO 23 NW   RMY N/A
07/21   79/62/71/-2/0.16/577/65           26 NNW AERO 23 NNW  RMY N/A TSTM
07/22   79/58/69/-4/T/656/74              20 WNW AERO 20 WNW  RMY N/A
07/23   79/62/71/-2/0.00/708/80           22 S   AERO 21 S    RMY N/A TSTM
07/24   78/59/69/-4/0.00/830/94           19 S   AERO 18 S    RMY N/A
07/25   71/64/68/-5/0.08/009/01           40 SSW AERO 41 SSW  RMY N/A
07/26   87/67/77/+4/0.01/765/87           27 WSW AERO 25 WNW  RMY N/A
07/27   87/65/76/+3/…./…/..           55 NW  AERO 58 NW   RMY N/A
07/28   72/61/67/-6/…./…/..           18 NNE AERO 18 NNE  RMY N/A

07/29 The low since midnight is 61F, the daily normal low is 64F

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

JULY 7: Record peak gust of 63 MPH,
        Surpasses previous record of 55 MPH set in 1989

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

RECORDS FOR JULY 29
HIGH 97F IN 1949
LOW 53F IN 1888,1914
PRECIP 1.53 INS IN 1901
PEAK GUST 40e MPH E IN 1941

RECORDS FOR JULY 30
HIGH 99F IN 1949
LOW 51F IN 1956
PRECIP 1.84 INS IN 1976
PEAK GUST 70e MPH SW 1944

TODAY’S REPORT PREPARED BY: Benjamin Turner