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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, AUGUST 3, 2018 
ALL TIMES ARE IN EASTERN STANDARD TIME

AFTERNOON THUNDERSTORM BRINGS HEAVY RAIN TO
GREAT BLUE HILL...

The day began once again with above seasonable
temperatures and humidity with an overnight low of
74. If temperatures do not drop below 71F by 
midnight this will become a new daily record for high 
minimum temperature. The high so far today of 88F which 
occurred before the wind shift is 7 degrees above the 
daily normal of 81F. Temperatures took a sharp drop after 
the wind shifted from the SSW to the WNW this afternoon 
and we observed a temperature of 74F during the storm. 
The rain, heavy at times, began around 12:35 P.M. and 
continued until just after the 1:00 P.M. observation for 
a storm total of 0.19 ins so far today. 

PRELIMINARY STATS FOR JULY 2018

TEMPERATURE, Deg. F
Avg. Max. 83.9 [+3.1]
Avg. Min. 63.7 [+0.8]
Mean      73.8 [+1.9]
24-hour corrected mean: 73.6
Max. for month: 94F on  1st and 3rd
Min. for month: 54F on  7th

COOLING DEGREE DAYS
Total cooling units:   296 [+74]
Total for the season:  455 [+104]
Total for last season: 421

PRECIPITATION, Inches
Total: 3.84 [-0.18]
Greatest in 24 hrs: 1.36 in on 17th-18th

WIND, mph
Avg. uncorrected wind speed: 9.8
Avg. corrected wind speed: 10.4
Prevailing wind direction: S at 19%
Peak gust and direction: 41 SSW on 26th  

SUNSHINE:
Campbell-Stokes card minutes: N/A (not yet finalized)
Astronomical total minutes: N/A (not yet finalized)

BHO Warmest July Mean Temperature (24-hr corrected mean), 
deg F (1885-2018):

1)  75.1 in 2010
2)  74.9 in 1952
3)  74.1 in 1994
    74.1 in 2013
5)  74.0 in 2011
    74.0 in 2016
7)  73.8 in 1999
8)  73.6 in 2018
9)  73.5 in 1949
10) 73.2 in 2012

Today's Observations:

7 A.M.
Weather: Very light drizzle, scattered stratocumulus, 
broken cirrostratus 
Temperature: 77F; Dew Point: 73F; Wind: SSW at 7 kts
Sea-level pressure: 30.18 ins. Hg, rising, then more slowly
Visibility: 40 miles, distant fog in all directions 
6-hr Max temp: 77F
6-hr Min temp: 74F
24-hr Precip: Trace 
BHO SA 1155 14 SCT E250 BKN 40L- 219/77/73/2107/018/ 
PCPN VRY LGT L-E55 DSNT FG ALQDS/ 8/501 51006 10077 20074 

10 A.M.
Weather: Scattered cumulonimbus, broken stratocumulus,
broken altostratus 
Temperature: 83F; Dew Point: 72F; Wind: WSW at 8 kts
Sea-level pressure: 30.18 ins. Hg, steady
Visibility: 40 miles, distant haze
3-hr Precip: 0.00 ins.  
BHO SA 1455 25 SCT E35 BKN 55 BKN 40 219/83/72/2408/018/ 
DSNT HZ ALQDS/ 8/510 55000 

1 P.M.
Weather: Heavy rain and thunderstorm, scattered cumulonimbus, 
broken stratocumulus, broken altostratus, few stratus fractus 
drifting below the summit 
Temperature: 74F; Dew Point: 70F; Wind: NW at 11 kts,
Wind: Shifted from SSW- WNW at 12:35 P.M.,
Peak Wind: 30 kts (35 MPH) at 12:52 P.M.
Sea-level pressure: 30.15 ins. Hg, falling steadily 
Visibility: 30 miles, except SSE and N 2 miles, distant fog
6-hr Max temp: 88F
6-hr Min temp: 74F
6-hr precip: 0.19 ins.
BHO SA 1755 31 SCT E40 BKN 100 BKN 30R+ 210/74/70/3120G30/015/ 
FEW STFA DRFTG BLO SMT RB35 BCMG R+45 BCMG R-55 TSB40 LTG DSNT 
NE TS NE-E MOV NE VSBY 2 SSE AND N WSHFT 35 PK WND 3130/52 DSNT 
FG ALQDS/ 8/520 58009 MANUAL 6019/ ASOS 60016 10088 20074 

SUMMARY FOR THURSDAY, AUGUST 2, 2018 

TEMPERATURE (DEGREES F)
MAX.....92   NORMAL.....81
MIN.....74   NORMAL.....63
MEAN....83   NORMAL.....72

DEPARTURE FROM 30-YEAR NORMAL........................+11
TOTAL DEPARTURE FOR THE MONTH........................+13 [+6.3 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY..............18   DEPARTURE.........+11
TOTAL COOLING UNITS FOR THE MONTH..............27   DEPARTURE.........+13
TOTAL COOLING UNITS FOR THE SEASON............482   DEPARTURE........+117
TOTAL COOLING UNITS LAST SEASON TO DATE.......443   DEPARTURE.........+39

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY.....................30 SW   AT  8:21 A.M.
                   AERO..........................28 SW   AT  6:50 P.M.* 
                   ASOS..........................30 WSW  AT  8:21 A.M.
                   DAVIS.........................32 W    AT  8:21 A.M. RMY 31
FASTEST MILE FOR YESTERDAY.......................22 WSW  AT 11:02 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE....................21 SW   AT  7:00 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE...................22 W    AT 11:05 A.M.
AVERAGE WIND SPEED AND DIRECTION...............14.5 SW
                   ASOS........................13.8
                   DAVIS.......................14.1 SW   [234 deg.]
*Last of several occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.15
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........0.00  DEPARTURE......-0.30
                         ASOS..............0.00 
TOTAL PRECIPITATION FOR THE YEAR..........34.01  DEPARTURE......+2.90
                         ASOS.............35.58

PRELIMINARY CLIMATE SUMMARY FOR JULY-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

7/01 94/72/83/+13/0.00/667/73       21 ESE AERO 18 ESE RMY 19 
7/02 90/68/79/+9/0.00/858/94        21 S   AERO 21 S   RMY 22
7/03 94/69/82/+11/0.00/657/72       20 SSW AERO 18 SW  RMY 19 TSTM
7/04 89/73/81/+10/0.00/884/97       17 NE  AERO 15 NE  RMY 16
7/05 91/73/82/+11/0.00/865/95       29 SSW AERO 28 SSW RMY N/A
7/06 80/59/70/-1/0.56/018/02        37 NNW AERO 38 SW  RMY 40 TSTM
7/07 78/54/66/-5/0.00/900/99        22 N   AERO 18 N   RMY N/A 
7/08 83/57/70/-2/0.00/890/98        23 S   AERO 21 S   RMY 22  
7/09 88/60/74/+2/0.00/852/94        23 SW  AERO 23 SW  RMY 24 
7/10 91/63/77/+5/0.10/751/83        24 W   AERO 22 W   RMY N/A
7/11 73/62/68/-4/0.63/705/78        28 NE  AERO 25 NE  RMY 27 TSTM
7/12 77/56/67/-5/0.00/867/96        16 NW  AERO 15 NW  RMY N/A 
7/13 84/61/73/+1/0.00/568/63        23 SSE AERO 23 SSE RMY 24
7/14 80/61/71/-1/0.00/540/60        18 S   AERO 16 S   RMY 19
7/15 84/65/75/+3/T/521/58           16 S   AERO 15 S   RMY 14 
7/16 83/67/75/+3/0.00/682/76        23 S   AERO 23 S   RMY 23 
7/17 88/67/78/+6/1.34/430/48        31 SW  AERO 30 SW  RMY 32 TSTM 
7/18 81/63/72/0/0.02/769/86         21 NW  AERO 22 NW  RMY 23 
7/19 80/56/68/-4/0.00/874/98        21 S   AERO 17 SSE RMY 19 
7/20 83/62/73/1/0.00/864/97         21 SE  AERO 17 ESE RMY 19
7/21 76/59/68/-4/0.00/738/83        23 ENE AERO 20 ENE RMY N/A
7/22 76/63/69/-3/..../009/01        29 ESE AERO 28 ESE RMY N/A
7/23 82/71/77/+5/..../327/37        32 S   AERO 30 S   RMY 32 
7/24 85/72/79/+7/T/698/79           31 S   AERO 29 S   RMY 29 
7/25 82/71/77/+5/..../159/18        35 SSE AERO 32 SSE RMY N/A 
7/26 83/69/76/+5/..../.../..        41 SSW AERO 39 SSW RMY N/A TSTM
7/27 88/69/79/+7/..../.../..        25 S   AERO 23 SSW RMY 26
7/28 87/71/79/+7/0.00/.../..        28 S   AERO 26 S   RMY 29
7/29 82/67/75/+3/0.00/.../..        18 W   AERO 16 W   RMY 18
7/30 82/64/73/+1/0.00/.../..        18 W   AERO 16 W   RMY 17
7/31 86/63/75/+3/0.00/.../..        16 SSW AERO 15 W   RMY N/A

DAILY RECORDS FOR JULY 2018

07/01/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 72F, 
          TIES PREVIOUS RECORD OF 72F SET IN 1968

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

8/1  82/66/74/+2/T/.../..           31 S   AERO 30 S   RMY 31
8/2  92/74/83/+11/0.00/.../..       30 SW  AERO 28 SW  RMY 31 

8/3 Low temp since midnight is 74F; normal low is now 63F

DAILY RECORDS FOR AUGUST 2018

None so far.

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

RECORDS FOR AUGUST 3
HIGH 96F IN 1930
LOW 50F IN 1976
PRECIP 1.45 INCHES IN 1979
PEAK GUST 52 MPH NW IN 2008 [TSTM]

RECORDS FOR AUGUST 4
HIGH 95F IN 1928
LOW 48F IN 1900
PRECIP 1.68 INS IN 1983
PEAK GUST 48 MPH SW IN 1974

TODAY'S REPORT PREPARED BY: Kaitlin Geagan