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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, JULY 17, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

WARM WITH A SOUTHERLY WIND AND LIMITED 
VISIBILITY ATOP GREAT BLUE HILL....

We observed hazy conditions, limiting visibility to less
than 40 miles on average. Building cumulus were seen in 
the afternoon hours, along with a more significant haze.
This was despite a gradually dropping humidity, reaching 
60% by noontime. A southerly wind averaging around 15 mph
has advected a significant amount of warm air into the 
region, bringing temperatures well above seasonal averages. 
The high so far today is 90F, 9 degrees above the daily 
normal maximum of 81F. The low since midnight is 72F, 9 
degrees above the average minimum of 63F.
    

PRELIMINARY STATS FOR JUNE 2019

TEMPERATURE, Deg. F
Avg. Max. 75.1 [+0.1]
Avg. Min. 57.3 [+0.2]
Mean      66.2 [+0.1]
24-hour corrected mean: 66.0
Max. for month: 88F on the 28th
Min. for month: 45F on the 4th

COOLING DEGREE DAYS
Total cooling units:    81 [-24]
Total for the season:   89 [-40]
Total for last season: 159

HEATING DEGREE DAYS
Total cooling units:     36  [-37]
Total for the season:  6254 [-122]
Total for last season: 5916

PRECIPITATION, Inches
Total: 4.08 [-0.23]
Greatest in 24 hrs: 1.30 ins. on the 10th-11th 

WIND, mph
Avg. uncorrected wind speed: 9.9
Avg. corrected wind speed: 10.5
Prevailing wind direction: S at 17%
Peak gust and direction: 41 W on 3rd  

SUNSHINE:
Campbell-Stokes card minutes: 14118 minutes of possible 26376 or 54%
Astronomical total minutes:   14674 minutes of possible 27416 or 54%


Today's Observations:

7 A.M.
Weather: Broken altocumulus
Temperature: 75F; Dew Point: 69F; Wind: SSW at 8 kts
Sea-level pressure: 29.96 ins. Hg, falling then rising
Visibility: 40 miles, hazy
6-hr Max temp: 75F
6-hr Min temp: 72F
24-hr Precip: 0.00 ins.
BHO SA 1155 E110 BKN 40 144/75/69/2108/996/ HAZY/ 8/070 
53002 10075 20072 

10 A.M.
Weather: Overcast altocumulus
Temperature: 81F; Dew Point: 71F; Wind: SW at 7G16 kts
Sea-level pressure: 29.94 ins. Hg, falling steadily
Visibility: 30 miles, hazy
3-hr Precip: 0.00 ins.
BHO SA 1455 E110 OVC 30 140/81/71/2407G16/994/ HAZY/ 
8/070 58004

1 P.M.
Weather: Scattered cumulus, broken altostratus, broken
cirrus
Temperature: 88F; Dew Point: 72F; Wind: WSW at 10G17 kts
Sea-level pressure: 29.89 ins. Hg, falling, then more quickly
Visibility: 30 miles, hazy
6-hr Max temp: 89F
6-hr Min temp: 75F
6-hr Precip: 0.00 ins. 
BHO SA 1755 50 SCT E160 BKN 250 BKN 30 124/88/72/2410G17/989/ 
HAZY/ 8/112 58016 10089 20075  

SUMMARY FOR TUESDAY, JULY 16, 2019 

TEMPERATURE (DEGREES F)
MAX.....86   NORMAL.....81
MIN.....65   NORMAL.....63
MEAN....76   NORMAL.....72

DEPARTURE FROM 30-YEAR NORMAL......................+4
TOTAL DEPARTURE FOR THE MONTH.....................+61 [+3.6 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY..............11   DEPARTURE.........+4
TOTAL COOLING UNITS FOR THE MONTH.............164   DEPARTURE........+57
TOTAL COOLING UNITS FOR THE SEASON............253   DEPARTURE........+17
TOTAL COOLING UNITS LAST SEASON TO DATE.......312   DEPARTURE........-59

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................23 W   AT  1:24 P.M. 
                   AERO.........................21 W   AT  2:48 P.M.  
                   ASOS.........................23 SW  AT  8:46 P.M. 
                   DAVIS........................24 W   AT  1:26 P.M.  RMY 21
FASTEST MILE FOR YESTERDAY......................16 W   AT  1:28 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE...................17 SW  AT  8:46 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..................17 W   AT  1:28 P.M.
AVERAGE WIND SPEED AND DIRECTION................8.3 SSW
                   ASOS.........................8.5
                   DAVIS........................8.4 WSW [244 deg.]


PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.13
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........1.45  DEPARTURE......-0.49
                         ASOS..............1.45
TOTAL PRECIPITATION FOR THE YEAR..........31.32  DEPARTURE......+2.41
                         ASOS.............31.22

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 71/54/63/+1/0.00/551/61               21 E   AERO 20 E   RMY 18
06/02 75/51/63/+1/0.02/417/46               23 S   AERO 21 S   RMY N/A
06/03 69/50/60/-2/0.02/753/83               41 W   AERO 39 W   RMY 43
06/04 70/45/58/-5/0.00/717/79               29 W   AERO 23 W   RMY N/A
06/05 81/57/69/+6/0.03/527/58               33 SSW AERO 33 SSW RMY N/A
06/06 75/64/70/+6/0.06/428/47               28 SSW AERO 28 SSW RMY N/A
06/07 80/59/70/+6/0.00/692/76               23 S   AERO 23 S   RMY 22
06/08 78/57/68/+4/0.00/885/97               23 ENE AERO 21 SW  RMY 21
06/09 78/55/67/+3/0.00/840/93               22 S   AERO 21 S   RMY 21
06/10 79/54/67/+2/0.29/712/78               26 SSE AERO 25 SSE RMY 33 
06/11 73/58/66/+1/1.03/247/27               32 NW  AERO 30 NW  RMY 35
06/12 75/52/64/-1/0.00/869/95               25 SSW AERO 25 S   RMY 28
06/13 55/49/52/-13/0.81/000/00              36 NE  AERO 35 NE  RMY 35
06/14 72/50/61/-5/0.00/540/59               38 W   AERO 39 W   RMY 38
06/15 79/54/67/+1/0.00/879/96               38 SSW AERO 41 SSW RMY 40
06/16 70/62/66/0/0.13/000/00                32 SW  AERO 35 SW  RMY N/A
06/17 74/62/68/+1/0.00/348/38               12 SSE AERO 18 NW  RMY 17
06/18 71/62/67/0/0.10/000/00                17*S   AERO 17 S   RMY 16
06/19 74/61/68/+1/0.00/101/11               16 SSE AERO 20 SSE RMY 19
06/20 69/61/65/-3/0.26/000/00               26 S   AERO 26 S   RMY 29
06/21 68/58/63/-5/0.75/018/02               32 NW  AERO 28 NW  RMY 33
06/22 77/56/67/-1/T/779/85                  33 NW  AERO 32 NW  RMY 35
06/23 82/59/71/+3/0.00/871/95               30 NW  AERO 25 WNW RMY 29
06/24 84/61/73/+4/0.00/779/85               22 NW  AERO 21 NW  RMY 22
06/25 73/61/67/-2/0.18/083/09               35 S   AERO 37 S   RMY 37
06/26 77/64/71/+2/0.00/559/61               12 ENE AERO 18 SE  RMY N/A
06/27 81/57/69/0/0.00/614/67                21 NE  AERO 18 NE  RMY N/A
06/28 88/64/76/+6/0.00/870/95               16 SW  AERO 18 SW  RMY N/A
06/29 80/66/73/+3/0.29/165/18               25 W   AERO 25 W   RMY 26
06/30 75/59/67/-3/0.13/430/47               31 N   AERO 30 N   RMY 35

*Estimated

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 83/58/71/+1/0.00/.../..               21 NNW AERO 21 NNW RMY N/A
07/02 82/65/74/+4/0.00/.../..               23 W   AERO 23 W   RMY 23
07/03 89/67/78/+7/0.00/.../..               18 S   AERO 18 S   RMY 18
07/04 88/68/78/+7/0.00/.../..               17 SSW AERO M  M   RMY 17
07/05 87/69/78/+7/0.00/.../..               21 SW  AERO M  M   RMY 21
07/06 90/71/81/+10/0.83/.../..              26 WNW AERO M  M   RMY N/A
07/07 78/64/71/0/0.00/.../..                30 NE  AERO M  M   RMY N/A
07/08 79/59/69/-3/0.00/.../..               16 N   AERO 18 SSW RMY N/A
07/09 85/61/73/+1/0.00/.../..               18 NW  AERO 16 NW  RMY 18
07/10 88/69/79/+7/0.00/.../..               20 ESE AERO 16 ESE RMY 17
07/11 81/67/74/+2/0.62/.../..               35 S   AERO 33 S   RMY 36
07/12 84/68/76/+4/0.00/.../..               31 WNW AERO 30 WNW RMY 32
07/13 85/65/75/+3/0.00/.../..               21 W   AERO 20 WSW RMY 20
07/14 87/68/78/+6/0.00/.../..               25 W   AERO 21 W   RMY 23
07/15 82/63/73/+1/0.00/.../..               24 WNW AERO 23 WNW RMY 22
07/16 86/65/76/+4/0.00/.../..               23 W   AERO 21 W   RMY 21

07/17 Low temp since midnight is 72F; normal low is 63F

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

RECORDS FOR JULY 17
HIGH 96F IN 1999
LOW 47F IN 1892
PRECIP 1.39 INS IN 1989
WIND 46 MPH WNW IN 1971

RECORDS FOR JULY 18
HIGH 96F IN 1991, 1999
LOW 54F IN 1892, 1956, 1971
PRECIP 1.65 INS IN 2000
WIND 43e MPH SW IN 1949

TODAY'S REPORT PREPARED BY: Benjamin Turner