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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, MAY 31, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

DRY AND WARMER THAN AVERAGE LAST DAY IN MAY...

Today temperatures have been warmer than average
with a max so for of 81F. This is already 10 degrees
above the daily normal of 71F. The morning began foggy
but dissipated by the 10:00 A.M. observation. Although
dew points were low and humidity dropped down to 30%, 
we still had a lingering distant haze which allowed 
for only 60 miles of visibility by 1:00 P.M. The wind
was mostly more the south/southwest today and picked
up this afternoon with a peak gust so far of 24 kts
(28 MPH) just after 1:00 P.M. The sky was mostly 
sunny with a mixture of cirrus clouds at each 
observation.

Today's Observations:

7 A.M.
Weather: Scattered cirrostratus, Few cirrus in all directions
Temperature: 62F; Dew Point: 54F; Wind: SW at 5 kts
Sea-level pressure: 30.13 ins. Hg, steady, then rising
Visibility: 70 miles, distant fog in all directions
6-hr Max temp: 62F
6-hr Min temp: 54F
24-hr Precip: 0.00 ins.
BHO SA 1155 300 SCT 70 203/62/54/2205/013/ FEW CI ALQDS DSNT FG
ALQDS/ 8/005 51005 10062 20054

10 A.M.
Weather: Scattered cirrostratus, scattered cirrus, Few distant 
cumulus S and SW
Temperature: 75F; Dew Point: 51F; Wind: SSW at 8 kts
Sea-level pressure: 30.10 ins. Hg, falling, then more slowly
Visibility: 60 miles, distant haze in all directions
3-hr Precip: 0.00 ins.
BHO SA 1455 250 SCT 350 SCT 60 194/75/51/2008/010/ FEW DSNT CU S 
AND SW DSNT HZ ALQDS/ 56009
 
1 P.M.
Weather: Scattered cirrostratus, scattered cirrus
Temperature: 79F; Dew Point: 45F; Wind: S at 12G22 kts
Sea-level pressure: 30.05 ins. Hg, falling, then more rapidly
Visibility: 60 miles, distant haze in all directions 
6-hr Max temp: 81F
6-hr Min temp: 62F
6-hr precip:  0.00 ins.
BHO SA 1755 170 SCT 250 SCT 60 176/79/45/1912G22/005/ DSNT HZ ALQDS/ 
58018 10081 20062

SUMMARY FOR WEDNESDAY, MAY 30, 2018

TEMPERATURE (DEGREES F)
MAX.....72   NORMAL.....70
MIN.....59   NORMAL.....52
MEAN....66   NORMAL.....61

DEPARTURE FROM 30-YEAR NORMAL.........................+5
TOTAL DEPARTURE FOR THE MONTH.......................+146 [+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.........-109
TOTAL HEATING UNITS FOR THE SEASON..........5847   DEPARTURE.........-451
TOTAL HEATING UNITS LAST SEASON TO DATE.....5658   DIFFERENCE........+189

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............1   DEPARTURE...........0
TOTAL COOLING UNITS FOR THE MONTH..............59   DEPARTURE.........+38
TOTAL COOLING UNITS FOR THE SEASON.............59   DEPARTURE.........+36
TOTAL COOLING UNITS LAST SEASON TO DATE........56   DEPARTURE..........+3

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................21 S    AT 8:03 P.M.*
                   AERO.........................20 S    AT 8:02 P.M. 
                   ASOS.........................21 SSW  AT 8:04 P.M.
                   DAVIS........................21 M    AT 7:48 P.M.** RMY N/A
FASTEST MILE FOR YESTERDAY......................14 S    AT 9:23 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE...................15 SSW  AT 9:26 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE..................15 M    AT 7:48 P.M.**
AVERAGE WIND SPEED AND DIRECTION...............9.3 NE
                   ASOS........................9.8
                   DAVIS.......................9.2 M
 * Last of multiple occurrences 
** Davis direction malfunctioning 

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.16
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........2.00  DEPARTURE......-1.96
                         ASOS..............1.95  
TOTAL PRECIPITATION FOR THE YEAR..........27.31  DEPARTURE......+4.98
                         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 Low temp since midnight is 54F; normal low is now 52F

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 MAY 31
HIGH 92F IN 1944,1987,2013
LOW 35F IN 1961
PRECIP 5.02 INS 1984 (RECORD FOR MAY)
PEAK GUST 54e MPH WNW IN 1945

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

TODAY'S REPORT PREPARED BY: Kaitlin Geagan / Devin Richardt