Saturday, June 17, 2017

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, JUNE 17, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME

HEAVY RAINFALL FRIDAY EVENING BRINGS OVER TWO INCHES…
DRIZZLE AND LOW CLOUDS WITH HIGH HUMIDITY TODAY…

Rain that began mid-afternoon on Friday became heavy
toward evening and brought a total of 2.15 inches of
precipitation. Most of this fell in six hours between
3 PM and 9 PM EST, and the greatest in one hour was
0.58 inches from 7-8 PM EST as measured by ASOS.
Drizzle continued after midnight until shortly after
10 AM EST this morning, with only a trace being
observed after the 7 AM EST observation. Dense fog
early this morning gradually lifted enough for the
visibility to climb only to about 8 miles by early
afternoon. The dew point has been climbing all day
from the mid-50s late yesterday to the mid-60s by
this afternoon as more humid air moves into the area.
The temperature has only climbed to 70F with no
sunshine so far today. The wind has become very light
today with only eight miles of wind being recorded
over the four hours from 11 AM to 3 PM EST.

Today’s Observations:

7 A.M.
Weather: Sky obscured in light drizzle and dense fog
Temperature: 59F; Dew Point: 59F; Wind: NNE at 6 kts,
Wind: Light
Sea-level pressure: 29.98 ins. Hg, falling then rising
Visibility: 1/16 mile
6-hr Max temp: 59F
6-hr Min temp: 58F
24-hr precip: 2.15 in.
BHO SA 1155 W2 X 1/16L-F 151/59/59/0306/998/ WND LGT/ 8////
53004 6000/ 70215 10059 20058

10 A.M.
Weather: Sky partly obscured in light drizzle and fog,
overcast nimbostratus, precipitation very light
Temperature: 63F; Dew Point: 62F; Wind: NNE at 5 kts
Wind: Light
Sea-level pressure: 29.99 ins. Hg, rising slightly
Visibility: 1 mile; variable 1/2 to 1 1/2 miles
3-hr precip: Trace
BHO SA 1455 -X E3 OVC 1VL-F 155/63/62/0305/999/ F4 VSBY 1/2V11/2
PCPN VRY LGT WND LGT/ 8/72/ 50004 6000/

1 P.M.
Weather: Overcast stratus, few lower stratus fractus,
distant thin fog all quadrants, hazy
Temperature: 67F; Dew Point: 64F; Wind: NNE at 1 kts (estim.)
Sea-level pressure: 29.96 ins. Hg, falling
Visibility: 8 miles, distant fog in all directions
3-hr precip: Trace
6-hr Max temp: 67F
6-hr Min temp: 59F
BHO SA 1755 E10 OVC 8 146/67/64/E0301/996/ FEW LWR STFRA DSNT
THN FG ALQDS HAZY WND LGT/ 8/6// 56009 6000/ 10067 20059

SUMMARY FOR FRIDAY, JUNE 16, 2017

TEMPERATURE (DEGREES F)
MAX…..70 NORMAL…..75
MIN…..56 NORMAL…..57
MEAN….63 NORMAL…..66

DEPARTURE FROM 30-YEAR NORMAL…………………….-3
TOTAL DEPARTURE FOR THE MONTH…………………….+9 [+0.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………2 DEPARTURE………..0
TOTAL HEATING UNITS FOR THE MONTH…………..61 DEPARTURE……….+5
TOTAL HEATING UNITS FOR THE SEASON………..5723 DEPARTURE……..-636
TOTAL HEATING UNITS LAST SEASON TO DATE……5282 DIFFERENCE…….+441

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0 DEPARTURE……….-3
TOTAL COOLING UNITS FOR THE MONTH…………..55 DEPARTURE………+15
TOTAL COOLING UNITS FOR THE SEASON…………111 DEPARTURE………+47
TOTAL COOLING UNITS LAST SEASON TO DATE……..81 DEPARTURE………+30

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….28 S AT 6:18 A.M.
AERO……………………29 S AT 6:18 A.M.
ASOS……………………29 S AT 6:18 A.M.
DAVIS…………………..27 S AT 6:17 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………20 SSE AT 6:19 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………21 SSE AT 6:19 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..21 SSE AT 6:19 A.M.
AVERAGE WIND SPEED AND DIRECTION………….10.1 SSE
ASOS…………………..8.8
DAVIS………………….8.1 SSE [152 DEG.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….2.15 DEPARTURE……+2.00
ASOS…………..2.15
TOTAL PRECIPITATION FOR THE MONTH……….5.32 DEPARTURE……+2.74
ASOS…………..5.38
TOTAL PRECIPITATION FOR THE YEAR……….30.66 DEPARTURE……+5.42
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/…/.. 25 W AERO 28 WNW RMY 28
6/14 78/56/67/+1/0.02/…/.. 20 S AERO 20 S RMY 20
6/15 75/54/65/-1/0.00/…/.. 25 SSW AERO 29 S RMY 30
6/16 70/56/63/-3/…./…/.. 28 S AERO 29 S RMY N/A

6/17 Low temp since midnight is 58F; normal low is now 58F

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

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

RECORDS FOR JUNE 17
HIGH 93F IN 1894
LOW 44F IN 1920
PRECIP 2.79 INS 2001 (Sub-Tropical storm ALLISON)
PEAK GUST 55e MPH S IN 1977

RECORDS FOR JUNE 18
HIGH 93F IN 1929,1994
LOW 39F IN 1920
PRECIP 3.36 INS 1998
PEAK GUST 48e MPH W IN 1943

TODAY’S REPORT PREPARED BY: Mike Iacono