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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, JUNE 1, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

MAY ENDS DRIER AND WARMER THAN AVERAGE...
MAY TIED FOR THIRD WARMEST ON RECORD...

Overall May ended drier and warmer than average. The 
mean temperature for the month is 61.8F which is 4.7 
degrees above monthly normal of 57.1F. We measured 
2.00 ins. of rainfall this month, which is 2.11 ins. 
below the monthly normal of 4.11 ins. 
June began with a dense fog this morning with variable
visibility and stratus fractus moving above and below
the summit. The fog began to burn off mid-morning but
we remained at 25 miles for visibility due to a distant
haze at all other observations. The air was very humid
today and we had a high dew point of 70F at 1:00 P.M.
The pressure has been dropping throughout the day causing
skies to be remain overcast all day so far with only a few
breaks midmorning. We had two short rain showers move past
the observatory between 11:00 A.M- 1:00 P.M. leaving only
a trace of precipitation so far today. Temperatures continued
the above seasonable trend with a max of 78F so far today.
This already 7 degrees above the daily normal of 71. The 
wind was from the south and light for most of the day today.

PRELIMINARY STATS FOR MAY 2018

TEMPERATURE, Deg. F
Avg. Max. 72.2 [+5.9]
Avg. Min. 51.3 [+3.5]
Mean      61.8 [+4.7]
24-hour corrected mean: 61.0
Max. for month: 90F on 3rd
Min. for month: 39F on 1st

HEATING DEGREE DAYS
Total heating units:    154 [-114]
Total for the season:  5847 [-456]
Total for last season: 5662

COOLING DEGREE DAYS
Total cooling units:   62 [+40]
Total for the season:  62 [+38]
Total for last season: 56

PRECIPITATION, Inches
Total: 2.00 ins. [-2.11]
Greatest in 24 hrs: 0.74 ins. on 15th

SNOWFALL, Inches
Total: 0.0 ins. 
Greatest in 24 hrs: 0.0 ins. 

WIND, mph
Avg. uncorrected wind speed: 10.3
Avg. corrected wind speed: 10.8
Prevailing wind direction: SSW at 14%
Peak gust and direction: 51 NW on 15th

SUNSHINE:
Campbell-Stokes card minutes: N/A
Astronomical total minutes: N/A

BHO Warmest May Mean Temperature (24-hour adjusted mean), deg F (1885-2018):

1) 61.5 in 2015
2) 61.4 in 1991
3) 61.0 in 1944
   61.0 in 2018
5) 60.9 in 2010
6) 59.4 in 1911
   59.4 in 1959
8) 59.3 in 1964
   59.3 in 2012


Today's Observations:

7 A.M.
Weather: Overcast status, few stratus fractus drifting
below the summit and occasionally over the summit, fog
Temperature: 65F; Dew Point: 63F; Wind: SSW at 6 kts,
Wind: Light
Sea-level pressure: 29.88 ins. Hg, falling, then more slowly
Visibility: 3 miles, variable 1/2 to 1 mile. 
6-hr Max temp: 65F
6-hr Min temp: 63F
24-hr Precip: 0.00 ins.
BHO SA 1155 –X E6 OVC 3F 118/65/63/2106G12/988/ FEW STRA DRFTG 
BLO SMT AND OCNL OVR SMT VSBY 1/2V1 WND LGT/ 8/6// 56006 10065 
20063

10 A.M.
Weather: Scattered stratus fractus, broken stratocumulus,
overcast stratus, break in overcast overhead, thin spots
in overcast 
Temperature: 75F; Dew Point: 68F; Wind: SSW at 6 kts,
Wind: Light
Sea-level pressure: 29.87 ins. Hg, falling, then more slowly
Visibility: 25 miles, distant haze in all directions
3-hr Precip: 0.00 ins.
BHO SA 1455 6 SCT E15 BKN E30 OVC 25 114/75/68/2106/987/ BINOVC 
OVHD THN SPTS IOVC DSNT HZ ALQDS WND LGT/ 8/6// 58004 
 
1 P.M.
Weather: Light drizzle beginning at 12:55 P.M., broken 
stratocumulus, overcast stratus 
Temperature: 77F; Dew Point: 70F; Wind: SSW at 7 kts
Sea-level pressure: 29.82 ins. Hg, falling, then more rapidly  
Visibility: 25 miles, distant haze in all directions 
6-hr Max temp: 78F
6-hr Min temp: 65F
6-hr precip:   Trace 
BHO SA 1755 E23 BKN E32 OVC 25L- 097/77/70/2007/982/ 
L-B55 PCPN VRY LGT DSNT HZ ALQDS/ 8/6// 58017 MANUAL 
600// 10078 20065

SUMMARY FOR THURSDAY, MAY 31, 2018

TEMPERATURE (DEGREES F)
MAX.....81   NORMAL.....71
MIN.....54   NORMAL.....52
MEAN....68   NORMAL.....61

DEPARTURE FROM 30-YEAR NORMAL.......................+7
TOTAL DEPARTURE FOR THE MONTH.....................+153 [+4.7 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............0   DEPARTURE...........-5
TOTAL HEATING UNITS FOR THE MONTH............154   DEPARTURE.........-114
TOTAL HEATING UNITS FOR THE SEASON..........5847   DEPARTURE.........-456
TOTAL HEATING UNITS LAST SEASON TO DATE.....5662   DIFFERENCE........+185

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............3   DEPARTURE..........+2
TOTAL COOLING UNITS FOR THE MONTH..............62   DEPARTURE.........+40
TOTAL COOLING UNITS FOR THE SEASON.............62   DEPARTURE.........+38
TOTAL COOLING UNITS LAST SEASON TO DATE........56   DEPARTURE..........+6

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................28 S   AT 1:21 P.M.
                   AERO.........................28 S   AT 1:19 P.M. 
                   ASOS.........................30 SSW AT 1:19 P.M.
                   DAVIS........................30 M   AT 1:19 P.M.** RMY 29
FASTEST MILE FOR YESTERDAY......................23 S   AT 1:19 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE...................23 SSW AT 1:21 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE..................23 M   AT 1:21 P.M.**
AVERAGE WIND SPEED AND DIRECTION..............12.4 S
                   ASOS.......................12.5
                   DAVIS......................12.3 M
 ** Davis direction malfunctioning 

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.12
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........2.00  DEPARTURE......-2.11
                         ASOS..............1.95  
TOTAL PRECIPITATION FOR THE YEAR..........27.31  DEPARTURE......+4.83
                         ASOS.............28.87

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE.........0.0
TOTAL SNOWFALL FOR THE MONTH................0.0  DEPARTURE.........0.0
TOTAL SNOWFALL FOR THE SEASON..............92.8  DEPARTURE.......+30.0

PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/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

5/01 65/39/52/-1/0.00/0.0/625/74    25 WNW AERO 21 WNW RMY 25
5/02 88/59/74/+21/0.00/0.0/584/69   37 WSW AERO 29 WSW RMY 35 
5/03 90/67/79/+26/0.13/0.0/433/51   36 SW  AERO 32 WSW RMY 36  
5/04 84/67/74/+20/0.05/0.0/102/12   39 SSW AERO 37 SSW RMY N/A
5/05 73/54/64/+10/0.00/0.0/615/72   56 W   AERO 55 W   RMY N/A
5/06 65/48/57/+3/0.21/0.0/000/00    24 NE  AERO 18 NE  RMY 21
5/07 62/49/56/+1/0.00/0.0/713/83    26 ENE AERO 22 NE  RMY 24
5/08 73/46/60/+5/0.00/0.0/852/99    25 SSE AERO 21 ESE RMY 23 
5/09 74/48/61/+6/0.00/0.0/768/89    23 ESE AERO 18 ESE RMY 21 
5/10 73/48/61/+6/0.03/0.0/355/41    33 S   AERO 30 S   RMY 32 
5/11 70/51/61/+5/0.00/0.0/703/81    26 WNW AERO 24 NW  RMY 28
5/12 51/47/49/-7/0.19/0.0/000/00    25 E   AERO 23 E   RMY N/A
5/13 58/46/52/-4/T/0.0/392/45       20 S   AERO 17 S   RMY 16 
5/14 73/47/60/+3/T/0.0/551/63       23 S   AERO 18 S   RMY 21
5/15 83/54/69/+12/0.74/0.0/333/38   51 NW  AERO 50 NW  RMY 54 TSTM
5/16 56/49/53/-4/T/0.0/272/31       32 ENE AERO 28 ENE RMY 30
5/17 72/51/62/+5/0.02/0.0/000/00    17 SW  AERO 14 SW  RMY N/A
5/18 62/43/53/-5/0.00/0.0/467/53    35 ENE AERO 33 ENE RMY N/A
5/19 57/43/50/-8/.../0.0/133/15     22 E   AERO 17 E   RMY N/A
5/20 77/54/66/+8/.../0.0/000/00     33 SW  AERO 31 SW  RMY 33 TSTM
5/21 75/52/64/+5/0.00/0.0/861/97    22 W   AERO 18 W   RMY 20
5/22 68/51/60/+1/0.04/0.0/071/08    23 SSW AERO 21 S   RMY 22
5/23 82/51/67/+8/0.06/0.0/.../..    33 NNW AERO 33 NNW RMY 34 TSTM
5/24 74/50/62/+3/0.00/0.0/.../..    28 SSW AERO 25 SSW RMY 27 
5/25 86/50/68/+8/0.00/0.0/.../..    40 W   AERO 39 W   RMY 43
5/26 88/61/75/+15/..../0.0/.../..   38 ENE AERO 38 ENE RMY 39
5/27 61/47/54/-6/..../0.0/.../..    32 ENE AERO 30 ENE RMY N/A
5/28 60/48/54/-7/..../0.0/.../..    23 S   AERO 21 S   RMY N/A
5/29 85/56/71/+10/0.00/0.0/.../..   23 WSW AERO 23 WSW RMY N/A
5/30 72/59/66/+5/0.00/0.0/.../..    21 S   AERO 20 S   RMY 21 
5/31 81/54/68/+7/0.00/0.0/.../..    28 S   AERO 28 S   RMY 29 

PRELIMINARY CLIMATE SUMMARY FOR MAY 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 Low temp since midnight is 62F; normal low is now 53F

DAILY RECORDS FOR MAY 2018

5/03/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
         BREAKS PREVIOUS RECORD OF 66F SET IN 2001

5/04/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
         BREAKS PREVIOUS RECORD OF 66F SET IN 2001

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

RECORDS FOR JUNE 1
HIGH 90F IN 1937,2013
LOW 36F IN 1945 [Record for month]
PRECIP 2.28 INS IN 1992
PEAK GUST 51e MPH SE IN 1952

RECORDS FOR JUNE 2
HIGH 91F IN 1895
LOW 41F IN 1907, 1929
PRECIP 2.36 INS IN 1982
SNOWFALL TRACE IN 1907 (IP)
PEAK GUST 63 MPH NW IN 2000

TODAY'S REPORT PREPARED BY: Kaitlin Geagan