Thursday, September 5, 2019

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, SEPTEMBER 5, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

EXCELLENT VISIBILITY WITH A LIGHT SEA BREEZE
KICKING IN LATER IN THE DAY….

We observed an almost perfect visibility of 85 miles
throughout the day. Wind was light, but shifted from
S-E around noon. The highest gust so far today is 23 mph
earlier this morning. Skies became gradually cloudier,
being completely overcast with cirrostratus clouds
shortly following the 1 P.M. observation. Conditions
were dry, with dew points only in the upper 40s.
The high so far today is 68F, which is 7 degrees
below the daily normal maximum of 75F. The low since
midnight is 54F, which is 4 degrees below the normal
minimum of 58F.

PRELIMINARY STATS FOR AUGUST 2019

TEMPERATURE, Deg. F
Avg. Max. 80.4 [+1.2] Avg. Min. 62.1 [+0.3] Mean      71.5 [+1.0] 24-hour corrected mean: 70.5
Max. for month: 92F on the 19th
Min. for month: 51F on the 26th

COOLING DEGREE DAYS
Total cooling units:   211 [+22] Total for the season:  619 [+82] Total for last season: 753

PRECIPITATION, Inches
Total: 1.83 [-2.21] Greatest in 24 hrs: N/A

WIND, mph
Avg. uncorrected wind speed: 9.1 mph
Avg. corrected wind speed:   9.8 mph
Prevailing wind direction: N/A
Peak gust and direction: N/A

SUNSHINE:
Campbell-Stokes card minutes: N/A
Astronomical total minutes:   N/A

Today’s Observations:

7 A.M.
Weather: Scattered cirrus
Temperature: 58F; Dew Point: 49F; Wind: S at 6 kts,
Wind: Light
Sea-level pressure: 30.09 ins. Hg, falling then rising
Visibility: 85 miles
6-hr Max temp: 62F
6-hr Min temp: 54F
24-hr Precip: 0.00 ins.
BHO SA 1155 250 SCT 85 190/58/49/3506/009/ WND LGT/
8/002 51013 10062 20054

10 A.M.
Weather: Broken cirrostratus, few cumulus
Temperature: 65F; Dew Point: 47F; Wind: NE at 6 kts,
Wind: Light
Sea-level pressure: 30.11 ins. Hg, falling then rising
Visibility: 85 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 E250 BKN 85 197/65/47/0506/011/ FEW CU
ALQDS WND LGT/ 8/108 50007

1 P.M.
Weather: Broken cirrostratus, few cumulus
Temperature: 68F; Dew Point: 46F; Wind: E at 4 kts,
Wind: Light and variable
Sea-level pressure: 30.10 ins. Hg, falling rapidly
Visibility: 85 miles
6-hr Max temp: 68F
6-hr Min temp: 58F
BHO SA 1755 E250 BKN 85 193/68/46/0904/010/ FEW
CU ALQDS WND L/V/ 8/108 58004 10068 20058

SUMMARY FOR WEDNESDAY, SEPTEMBER 4, 2019

TEMPERATURE (DEGREES F)
MAX…..83   NORMAL…..76
MIN…..61   NORMAL…..59
MEAN….72   NORMAL…..67

DEPARTURE FROM 30-YEAR NORMAL………………….+5
TOTAL DEPARTURE FOR THE MONTH………………….+2 [+0.3 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………7   DEPARTURE………+4
TOTAL COOLING UNITS FOR THE MONTH…………..12   DEPARTURE………-3
TOTAL COOLING UNITS FOR THE SEASON…………631   DEPARTURE……..+79
TOTAL COOLING UNITS LAST SEASON TO DATE…….791   DEPARTURE…….-160

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..30 SW  AT  2:10 P.M.
AERO…………………….28 SW  AT  2:08 P.M.
ASOS…………………….30 SSW AT  2:12 P.M.
DAVIS……………………30 SW  AT  1:37 P.M. RMY 30
FASTEST MILE FOR YESTERDAY………………….24 SW  AT  2:14 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….23 SSW AT  2:13 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………23 SSW AT  2:13 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..12.4 S
ASOS…………………..12.7
DAVIS………………….12.0 SSW [215 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.12
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….0.37  DEPARTURE……-0.09
ASOS…………..0.36
TOTAL PRECIPITATION FOR THE YEAR……….37.52  DEPARTURE……+2.03
ASOS………….37.40

PRELIMINARY CLIMATE SUMMARY FOR AUGUST 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

8/01  84/66/75/+3/0.00/755/87               18 NNW AERO 20 NW  RMY 17
8/02  83/61/72/0/0.00/804/93                18 WSW AERO 18 WSW RMY 18
8/03  84/66/75/+3/0.00/302/35               25 SW  AERO 26 SW  RMY 25
8/04  83/66/75/+3/0.00/732/85               21 NE  AERO 23 SW  RMY 25
8/05  81/58/70/-2/0.00/842/98               20 S   AERO 18 S   RMY 19
8/06  79/63/71/-1/0.00/282/33               15 S   AERO 14 S   RMY 17
8/07  82/66/74/+2/…./367/43               32 SSW AERO 35 SSW RMY 35
8/08  84/67/76/+4/…./588/69               30 SW  AERO 24 WNW RMY 29
8/09  82/63/73/+1/…./815/96               28 NW  AERO 25 NW  RMY 26
8/10  78/59/69/-2/…./720/85               32 NW  AERO 28 NW  RMY 28
8/11  78/55/67/-4/0.00/734/87               28 W   AERO 25 W   RMY 28
8/12  82/60/71/0/0.00/749/89                25 W   AERO 23 W   RMY 26
8/13  77/66/72/+1/0.02/059/07               25 W   AERO 24 WSW RMY 24
8/14  75/62/69/-2/…./452/54               24 ENE AERO 22 ENE RMY 22
8/15  77/59/68/-3/…./568/68               17 ESE AERO 15 SSE RMY 16
8/16  78/61/70/-1/…./732/88               20 E   AERO 17 ESE RMY 18
8/17  78/67/73/+2/…./099/12               14 SE  AERO 15 SE  RMY 15
8/18  88/70/79/+8/…./529/64               18 SSW AERO 18 SSW RMY 21
8/19  92/69/81/+11/…./…/..              25 WSW AERO 23 WSW RMY 25
8/20  87/66/77/+7/…./…/..               18 W   AERO 14 WSW RMY N/A
8/21  85/68/77/+7/0.12/…/..               33 SW  AERO 32 SW  RMY 33
8/22  88/68/78/+8/0.00/…/..               25 W   AERO 21 W   RMY 26
8/23  78/60/69/-1/0.04/…/..               23 N   AERO 18 N   RMY 24
8/24  72/55/64/-6/0.00/…/..               25 ENE AERO 21 ENE RMY 22
8/25  66/56/61/-8/0.00/…/..               31 ENE AERO 25 ENE RMY 29
8/26  71/51/61/-8/0.00/…/..               25 NE  AERO 21 NE  RMY 25
8/27  77/54/66/-3/0.00/…/..               18 SSW AERO 18 SSW RMY 17
8/28  78/59/69/0/…./…/..                21 SSE AERO 18 SSE RMY 20
8/29  83/63/73/+4/…./…/..               25 WNW AERO 21 WNW RMY 26
8/30  84/59/72/+4/…./…/..               30 SW  AERO 30 SW  RMY 28
8/31  79/61/70/+2/…./…/..               21 W   AERO 18 W   RMY 20

PRELIMINARY CLIMATE SUMMARY FOR AUGUST 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

9/01  73/56/65/-3/0.00/…/..                21 ENE AERO 14 ENE RMY 18
9/02  75/57/66/-2/0.37/…/..                39 W   AERO 41 W   RMY 41
9/03  77/61/69/+2/0.00/…/..                18 S   AERO 16 S   RMY N/A
9/04  83/61/72/+5/0.00/…/..                30 SW  AERO 28 SW  RMY 30

9/05 Low temp since midnight is 54F; normal low is 58F

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

RECORDS FOR SEPTEMBER 5
HIGH 90F IN 1971
LOW 45F IN 1906
PRECIP 1.37 INCHES IN 1907
PEAK GUST 46 MPH NW IN 1994

RECORDS FOR SEPTEMBER 6
HIGH 92F IN 1900, 2018
LOW 39F IN 1888
PRECIP 3.19 INCHES IN 1890
PEAK GUST 78e MPH SE IN 1979 (TROPICAL STORM DAVID)

TODAY’S REPORT PREPARED BY: Benjamin Turner and Rusty Monro