Friday, July 7, 2017

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, JULY 7, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME

LOW PRESSURE BRINGS MODERATE TO HEAVY RAIN
TO GREAT BLUE HILL

Skies were overcast all day as a low pressure front brought rain to
Great Blue Hill. The rain started light right before the 7 A.M. EST
observation and showers were on and off until more moderate rain moved
in, in the afternoon. The amount of precipitation that fell by 1 P.M. EST
was 0.34 inches. Winds shifted from the south to the E-ENE around 10 A.M.
bringing cooler air and fog to the hill. With this shift we also saw an
increase in wind speed. As the fog moved in the humidity went up to 97%
by 1 P.M. The cooler air has also made for below seasonable temperatures
with a high of 72F by 1 P.M. EST Normal being 80F.

PRELIMINARY STATS FOR JUNE 2017

TEMPERATURE, Deg. F
Avg. Max. 77.2 [+2.2] Avg. Min. 57.8 [+0.7] Mean      67.5 [+1.4] 24-hour corrected mean: 67.0
Max. for month: 94F on  12th
Min. for month: 45F on  6th

HEATING DEGREE DAYS
Total heating units: 63 [-10] Total for the season: 5725 [-651] Total for last season: 5282

COOLING DEGREE DAYS
Total cooling units: 145 [+40] Total for the season: 201 [+72] Total for last season: 157

PRECIPITATION, Inches
Total: 6.03 [+1.72] Greatest in 24 hrs: 2.19 in on 5th-6th

WIND, mph
Avg. uncorrected wind speed: 11.7
Avg. corrected wind speed: 12.1
Prevailing wind direction: W at 15%
Peak gust and direction: 48 N on 9th

SUNSHINE:
Campbell-Stokes card minutes: 15,030 minutes of possible 26,376 or 57%
Astronomical total minutes: 15,613 minutes of possible 27,417 or 57%

Today’s Observations:

7 A.M.
Weather: Overcast altostratus,few cumulus E-SSW,
distant bright sky along horizon to the north
Temperature: 67F; Dew Point: 63F; Wind: SSE at 5 kts,
Wind: Light
Sea-level pressure: 29.90 ins. Hg, falling, then more slowly
Visibility: 50 miles
6-hr Max temp: 67F
6-hr Min temp: 63F
24-hr precip: Trace
BHO SA 1155 110 OVC 50 126/67/63/1605/990/ FEW CU E-SSW
BRGHT SKY ALG HRZN DSNT N WND LGT/ 8/110 56013 10067 20063

10 A.M.
Weather: Light rain, overcast nimbostratus, few cumulus NW-S,
distant bright sky along horizon to the north
Temperature: 70F; Dew Point: 65F; Wind: ESE at 4 kts
Wind: Light
Sea-level pressure: 29.86 ins. Hg, falling, then more slowly
Visibility: 30 miles
3-hour precip: Trace
BHO SA 1455 60 OVC 30L- 117/70/65/1204/986/ FEW CU NW-S
BRGHT SKY ALG HRZN DSNT N WND LGT/ 8/120 55009

1 P.M.
Weather: Rain, sky obscured due to fog
Temperature: 65F; Dew Point: 64F; Wind: NE at 10 G20 kts
Sea-level pressure: 29.81 ins. Hg, falling, then more slowly
Visibility: 1/2 mile
6-hr Max temp: 72F
6-hr Min temp: 64F
6-hr precip: 0.34 inches
BHO SA 1755 W3 X 1/2RF 095/65/64/0510G20/981/ 8//// MANUAL 60034
ASOS 60033 56022 10072 20064

 

SUMMARY FOR THURSDAY, JULY 6, 2017

TEMPERATURE (DEGREES F)
MAX…..82   NORMAL…..80
MIN…..60   NORMAL…..62
MEAN….71   NORMAL…..71

DEPARTURE FROM 30-YEAR NORMAL……………………..0
TOTAL DEPARTURE FOR THE MONTH……………………+22 [+3.5 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………6   DEPARTURE……….+1
TOTAL COOLING UNITS FOR THE MONTH…………..56   DEPARTURE………+19
TOTAL COOLING UNITS FOR THE SEASON…………257   DEPARTURE………+91
TOTAL COOLING UNITS LAST SEASON TO DATE…….209   DEPARTURE………+48

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….21 SSW AT  2:17 P.M.
AERO……………………22 SSW AT  1:23 P.M.
ASOS……………………22  S  AT  8:34 P.M.
DAVIS…………………..21 SSW AT 12:42 P.M. RMY 21
FASTEST MILE FOR YESTERDAY…………………15 SSW AT  1:32 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………16  S  AT 11:41 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..16 SSW AT  1:25 P.M.
AVERAGE WIND SPEED AND DIRECTION………….10.7  S
ASOS………………….10.8
DAVIS………………….8.6  S [190 DEG.] *last of multiple occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.11
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….0.00  DEPARTURE……-0.65
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE YEAR……….31.37  DEPARTURE……+3.75
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings

 

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

6/1  78/55/67/+5/0.06/706/78               39 NW  AERO 39 NW  RMY 41
6/2  70/50/60/-2/T/652/72                  32 WNW AERO 35 WNW RMY 34
6/3  66/47/57/-5/0.01/472/52               23 NW  AERO 25 NW  RMY 24
6/4  71/49/60/-3/0.28/490/54               21 SSE*AERO 21 SW  RMY N/A
6/5  55/49/52/-11/1.20/000/00              32 NE  AERO 35 NE  RMY N/A
6/6  49/45/47/-16/1.36/000/00              40 ENE AERO 43 ENE RMY 43
6/7  65/47/56/-8/0.05/519/57               21 NNE AERO 18 NE* RMY 20
6/8  76/52/64/0/0.00/602/66                21 SSE AERO 21 SSE RMY 18
6/9  78/53/66/+2/0.16/438/48               48 N   AERO 54 N   RMY 52 TSTM
6/10 83/59/71/+6/0.00/722/79               25 SSW AERO 28 SSW RMY 27
6/11 89/64/77/+12/0.00/704/77              29 SW  AERO 32 WSW RMY 30
6/12 94/69/82/+17/0.00/851/93              28 W   AERO 29 W   RMY 28
6/13 92/67/80/+15/0.03/796/87              25 W   AERO 28 WNW RMY 28
6/14 78/56/67/+1/0.02/889/97               20 S   AERO 20 S   RMY 20
6/15 75/54/65/-1/0.00/870/95               25 SSW AERO 29 S   RMY 30
6/16 70/56/63/-3/2.14/073/08               28 S   AERO 29 S   RMY N/A
6/17 70/58/64/-3/0.01/000/00               18 S   AERO 18 S   RMY N/A
6/18 82/65/74/+7/T/394/43                  33 SSW*AERO 35 SSW RMY 37
6/19 82/67/75/+8/0.05/312/34               40 S   AERO 43 S   RMY 43
6/20 84/66/75/+7/0.25/651/71               38 SW  AERO 44 SW  RMY 40
6/21 83/64/74/+6/0.00/734/80               29 W   AERO 30 W   RMY 30
6/22 83/59/71/+3/0.00/779/85               23 W   AERO 22 W   RMY 21
6/23 88/66/77/+9/0.00/413/45               33 S   AERO 36 S   RMY 36 TSTM
6/24 84/68/76/+7/0.19/413/45               28 WNW AERO 31 WNW RMY 32
6/25 83/61/72/+3/T/688/75                  29 WNW AERO 35 WNW RMY 34
6/26 79/57/68/-1/0.00/843/92               24 W   AERO 24 W   RMY 23
6/27 74/55/65/-4/0.11/421/46               43 S   AERO 45 S   RMY 45 TSTM
6/28 76/52/64/-6/0.00/897/98               28 W   AERO 28 W   RMY 28
6/29 78/60/69/-1/0.00/055/06               30 SSW AERO 30 SSW RMY 32
6/30 82/65/74/+4/0.11/229/25               30 SSW AERO 32 SSW RMY 32

 

DAILY RECORDS FOR JUNE

6/12/17: DAILY RECORD MAXIMUM TEMPERATURE OF 94F,
BREAKS PREVIOUS RECORD OF 92F SET IN 1973

6/12/17: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 69F,
TIES PREVIOUS RECORD SET IN 1942

 

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

7/1  85/67/76/+6/T/…/..                  35 S   AERO 37 S   RMY 38
7/2  87/69/78/+8/T/…/..                  25 W*  AERO 28 W*  RMY 27
7/3  85/67/76/+5/0.00/…/..               28 W*  AERO 29 W   RMY 30
7/4  84/62/73/+2/0.00/…/..               17 W   AERO 17 W   RMY 18
7/5  82/62/72/+1/0.00/…/..               20 S   AERO 20 ENE RMY 20
7/6  82/60/71/0/0.00/…/..               21 SSW AERO 22 SSW RMY 21

7/7 Low temp since midnight is 63F; normal low is now 62F

 

DAILY RECORDS FOR JULY

None so far.

 

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: Kaitlin Ann Geagan and Doug Gifford