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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, JUNE 21, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

ABOVE AVERAGE TEMPERATURES AND DRY CONDITIONS 
CONTINUE FOR A PLEASANT SUMMER SOLSTICE!...

Today is the longest day of the year in the northern
hemisphere and we continued to have above normal 
temperatures and dry conditions. So far we have a 
max of 81F, which is 4 degrees above to daily normal 
of 77F. The air was dry again today making for another 
great visibility day with 80 miles by 10:00 A.M. A 
distant haze was observed at 1:00 P.M. limiting 
visibility to 60 miles WSW-WNW. The sky remained partly 
cloudy today with cumulus clouds beginning to form 
around the 10:00 A.M. observation. The wind was coming 
from the WSW/W but it became light and variable midday. 
In the afternoon the wind picked up and began steadily 
coming from the ENE.   

Today's Observations:

7 A.M.
Weather: Scattered altocumulus, broken altocumulus, few 
cumulus distant E-SSW  
Temperature: 66F; Dew Point: 59F; Wind: NW at 7 kts
Sea-level pressure: 29.79 ins. Hg, rising, then more slowly  
6-hr Max temp: 66F
6-hr Min temp: 62F
24-hr Precip: 0.00 ins.
BHO SA 1155 120 SCT E170 BKN 70 087/66/59/3207/979/ 
FEW CU DSNT E-SSW/ 8/130 51007 10066 20062

10 A.M.
Weather: Scattered altocumulus, few cumulus in all
directions, moderate cumulus forming north
Temperature: 79F; Dew Point: 56F; Wind: NE at 4 kts,
Wind: Light and variable, direction estimated 
Sea-level pressure: 29.80 ins. Hg, rising, then more slowly 
Visibility: 80 miles
3-hr Precip: 0.00 ins
BHO SA 1455 170 SCT 80 093/79/56/E0404/980/ FEW CU ALQDS MDT 
CU FRMG N WND L/V/ 8/230 51006   

1 P.M.
Weather: Scattered cumulus, scattered cirrostratus 
Temperature: 77F; Dew Point: 54F; Wind: ENE at 10G16 kts
Sea-level pressure: 29.78 ins. Hg, falling, then more rapidly 
Visibility: 80 miles, except WSW-WNW 60 miles thin distant 
haze WSW-WNW
6-hr Max temp: 81F
6-hr Min temp: 66F
6-hr precip: 0.00 ins.
BHO SA 1755 35 SCT 200 SCT 80 085/77/54/0610G16/978/ VSBY 
60 WSW-WNW THN DSNT HZ WSW-WNW/ 8/800 56008 10081 20066  

SUMMARY FOR WEDNESDAY, JUNE 20, 2018

TEMPERATURE (DEGREES F)
MAX.....81   NORMAL.....76
MIN.....58   NORMAL.....59
MEAN....70   NORMAL.....68

DEPARTURE FROM 30-YEAR NORMAL.........................+2
TOTAL DEPARTURE FOR THE MONTH.........................-3 [-0.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............0   DEPARTURE...........-2
TOTAL HEATING UNITS FOR THE MONTH.............62   DEPARTURE...........-2
TOTAL HEATING UNITS FOR THE SEASON..........5909   DEPARTURE.........-457
TOTAL HEATING UNITS LAST SEASON TO DATE.....5724   DIFFERENCE........+185

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............5   DEPARTURE..........+1
TOTAL COOLING UNITS FOR THE MONTH..............53   DEPARTURE..........-2
TOTAL COOLING UNITS FOR THE SEASON............115   DEPARTURE.........+36
TOTAL COOLING UNITS LAST SEASON TO DATE.......140   DEPARTURE.........-25

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................22 W AT  3:30 P.M.*
                   AERO.........................21 W AT  3:30 P.M.* 
                   ASOS.........................23 W AT  3:31 P.M.
                   DAVIS........................24 M AT 11:25 A.M.** RMY 23
FASTEST MILE FOR YESTERDAY......................16 W AT  3:31 P.M.*
MAXIMUM 2-MINUTE ASOS AVERAGE...................17 W AT  3:31 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE..................17 M AT  2:29 P.M.**
AVERAGE WIND SPEED AND DIRECTION...............8.1 SW
                   ASOS........................8.5
                   DAVIS.......................8.0
* Last of multiple occurrences
**Davis direction malfunctioning 

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..........1.13  DEPARTURE......-2.01
                         ASOS..............1.15  
TOTAL PRECIPITATION FOR THE YEAR..........28.45  DEPARTURE......+2.83
                         ASOS.............30.02

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

6/01 78/62/70/+8/T/009/01            21 S   AERO 21 S   RMY N/A
6/02 79/54/67/+5/T/353/39            26 ENE AERO 25 ENE RMY 27
6/03 59/45/52/-10/0.00/816/90        28 ENE AERO 25 ENE RMY N/A  
6/04 52/45/49/-14/0.82/000/00        29 ENE AERO 26 ENE RMY 29
6/05 64/47/56/-7/0.19/173/19         24 N   AERO 21 N   RMY 23  TSTM  
6/06 66/50/58/-5/0.00/373/41         23 S   AERO 21 S   RMY 22
6/07 69/50/60/-4/0.00/282/31         25 S   AERO 25 S   RMY 27 
6/08 79/52/66/+2/0.00/684/75         20 SW  AERO 17 SW  RMY 18
6/09 79/58/69/+5/0.00/767/84         22 W   AERO 21 W   RMY 22
6/10 72/56/64/-1/0.00/593/65         20 S   AERO 18 S   RMY 17
6/11 68/51/60/-5/0.00/594/65         21 ENE AERO 20 SSW RMY N/A
6/12 77/49/63/-2/0.00/814/89         37 SW  AERO 37 SW  RMY 39
6/13 74/56/65/0/T/284/31             35 SW  AERO 36 SW  RMY 36
6/14 77/61/69/+3/0.00/495/54         35 W   AERO 36 WNW RMY 37
6/15 68/53/61/-5/0.01/266/29         17 NNW AERO 16 WNW RMY 19
6/16 83/54/69/+3/0.00/.../..         25 NNW AERO 24 NNW RMY 25
6/17 86/63/75/+8/0.00/.../..         23 S   AERO 22 S   RMY N/A
6/18 86/64/75/+8/0.10/.../..         37 SSW AERO 37 SSW RMY 40  TSTM
6/19 81/64/73/+6/0.01/.../..         31 WSW AERO 32 WSW RMY 32 
6/20 81/58/70/+2/0.00/.../..         22 W   AERO 21 W   RMY 23 

6/21 Low temp since midnight is 62F; normal low is now 59F

DAILY RECORDS FOR JUNE 2018

None so far.

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

RECORDS FOR JUNE 21
HIGH 94F IN 2012
LOW 42F IN 1940
PRECIP 1.40 INS 1903
PEAK GUST 51 MPH SSW IN 2000

RECORDS FOR JUNE 22
HIGH 93F IN 1921, 2012
LOW 43F IN 1940
PRECIP 1.57 INS IN 1900
PEAK GUST 74 MPH NW IN 1988

TODAY'S REPORT PREPARED BY: Kaitlin Geagan