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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, OCTOBER 10, 2018 
ALL TIMES ARE IN EASTERN STANDARD TIME

A WARMER THAN USUAL FALL DAY WITH DECREASING HUMIDITY 
AND FAIR WEATHER....

Humidity has decreased from 92% this morning to 57% by
the 1 P.M. observation. Clouds have covered a little 
less than half of the sky throughout most of the day.
Winds have shifted slightly from southwest to west, with 
a speed around 15 mph on average. The temperature has 
reached a high of 82F so far today. This is 20 degrees 
above the daily normal maximum of 62F. The low 
since midnight is 65F, which is 20 degrees above our 
normal low of 45F.


PRELIMINARY STATS FOR SEPTEMBER 2018

TEMPERATURE, Deg. F
Avg. Max. 72.5 [+0.9]
Avg. Min. 58.6 [+4.0]
Mean 65.6 [+2.5]
24-hour corrected mean: 64.8
Max. for month: 92F on 3rd, 6th
Min. for month: 47F on 23rd

HEATING DEGREE DAYS
Total heating units: 87 [-30]
Total for the season: 87 [-55]
Total for last season: 93

COOLING DEGREE DAYS
Total cooling units: 110 [+50]
Total for the season: 863 [+266]
Total for last season: 707

PRECIPITATION, Inches
Total: 9.13 [+5.07]
Greatest in 24 hrs: 3.32 ins. on the 18th-19th

WIND, mph
Avg. uncorrected wind speed: 9.4
Avg. corrected wind speed: 10.1
Prevailing wind direction: NE [12% of total hours]
Peak gust and direction: 37 SSW

SUNSHINE:
Campbell-Stokes card minutes: 7608 minutes of possible 21582 or 35%
Astronomical total minutes: 7924 minutes of possible 22447 or 35%

BHO Lowest September Sunshine, hours (1886-2018):
1) 120.7 in 1934  [34%]
2) 126.8 in 2018  [35%]
3) 130.8 in 1889  [36%]
4) 131.1 in 1996  [36%]
5) 133.0 in 1907  [37%]

BHO Wettest Septembers, inches (1886-2018):
1) 12.37 in 1999
2) 11.04 in 1933
3) 10.23 in 1896
4) 10.00 in 1961
5) 9.62 in 1987
6) 9.58 in 1888
7) 9.36 in 1918
8) 9.13 in 2018
9) 8.81 in 1907
10) 8.78 in 1996      

Today's Observations:

7 A.M.
Weather: Scattered cirrus
Temperature: 68F; Dew Point: 65F; Wind: SW at 12G17 kts
Sea-level pressure: 30.11 ins. Hg, falling steadily       
Visibility: 20 miles, distant fog in all directions
6-hr Max temp: 68F
6-hr Min temp: 65F
24-hr Precip: 0.00 ins.   
BHO SA 1155 250 SCT 20 197/68/65/2312G17/011/ 
DSNT FG ALQDS/ 8/002 53001 10068 20065

10 A.M.
Weather: Scattered cumulus, scattered cirrus
Temperature: 76F; Dew Point: 67F; Wind: W at 08G18 kts 
Sea-level pressure: 30.08 ins. Hg, falling steadily
Visibility: 40 miles, distant haze in all directions
3-hr Precip: 0.00 ins.
BHO SA 1455 25 SCT 250 SCT 40 187/76/67/2708G18/008/ 
DSNT HZ ALQDS/ 8/102 58010

1 P.M.
Weather: Scattered cumulus
Temperature: 82F; Dew Point: 65F; Wind: WSW at 13G19 kts
Sea-level pressure: 29.99 ins. Hg, falling rapidly    
Visibility: 50 miles
6-hr Max temp: 82F
6-hr Min temp: 65F 
6-hr Precip: 0.00 ins.
BHO SA 1755 35 SCT 50 156/82/65/2413G19/999/ 
8/100 58031 10082 20065 
  
SUMMARY FOR TUESDAY, OCTOBER 9, 2018 

TEMPERATURE (DEGREES F)
MAX.....75   NORMAL.....63
MIN.....56   NORMAL.....45
MEAN....66   NORMAL.....54

DEPARTURE FROM 30-YEAR NORMAL......................+12
TOTAL DEPARTURE FOR THE MONTH.......................35 [+3.7 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............0   DEPARTURE........-11
TOTAL HEATING UNITS FOR THE MONTH..............52   DEPARTURE........-37
TOTAL HEATING UNITS FOR THE SEASON............139   DEPARTURE........-92
TOTAL HEATING UNITS LAST SEASON TO DATE.......121   DIFFERENCE.......+18

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............1  DEPARTURE..........+1
TOTAL COOLING UNITS FOR THE MONTH...............2  DEPARTURE..........-1
TOTAL COOLING UNITS FOR THE SEASON............865  DEPARTURE........+265
TOTAL COOLING UNITS LAST SEASON TO DATE.......723  DIFFERENCE.......+142

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................26 WSW AT 12:02 P.M.
                   AERO.........................28 SW  AT 7:48  A.M.
                   ASOS.........................29 SW  AT 7:44  A.M.
                   DAVIS........................30 WSW AT 7:43  A.M. RMY 29
FASTEST MILE FOR YESTERDAY......................19 SW  AT 8:00  A.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE...................20 SW  AT 8:15  A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..................21 WSW AT 11:46 A.M.
AVERAGE WIND SPEED AND DIRECTION..............13.6 SSW
                   ASOS.......................13.6 
                   DAVIS......................13.4 SW [220 deg.]   

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.14
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........1.40  DEPARTURE......+0.07
                         ASOS..............1.40 
TOTAL PRECIPITATION FOR THE YEAR..........48.48  DEPARTURE......+8.25
                         ASOS.............50.32 

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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

9/01 75/58/67/-1/0.00/521/66        17 NE  AERO 15 NE  RMY 16 
9/02 83/61/72/+4/0.00/684/87        20 SSW AERO 18 SSW RMY N/A 
9/03 92/68/80/+13/0.00/650/83       24 WSW AERO 22 WSW RMY 25
9/04 88/70/79/+12/0.00/695/89       17 W   AERO 16 W   RMY 17 
9/05 89/67/78/+11/0.00/638/82       23 SSW AERO 23 SSW RMY 25 
9/06 92/70/81/+14/0.56/488/63       29 NNW AERO 29 NNW RMY N/A TSTM
9/07 70/63/67/+1/0.01/000/00        24 NE  AERO 22 NE  RMY N/A 
9/08 68/54/61/-5/0.00/031/04        22 NE  AERO 18 NE  RMY 21
9/09 61/53/57/-9/0.00/000/00        23 NE  AERO 21 NE  RMY N/A
9/10 62/56/59/-6/..../000/00        30 E   AERO 28 E   RMY 28
9/11 75/61/68/+3/..../000/00        23 E   AERO 21 E   RMY N/A TSTM 
9/12 69/63/66/+1/..../000/00        21 ENE AERO 21 ENE RMY 21  TSTM 
9/13 68/62/65/+1/..../091/12        21 NE  AERO 21 NE  RMY N/A TSTM 
9/14 75/61/68/+4/..../233/31        13 NE  AERO 12 ENE RMY 12 
9/15 76/62/69/+5/0.01/218/29        14 SW  AERO 13 SW  RMY 13
9/16 84/61/73/+10/..../695/93       15 S   AERO 14 S   RMY N/A
9/17 82/64/73/+10/..../372/50       22 SSW AERO 22 SSW RMY N/A
9/18 74/67/71/+9/..../000/00        31 SSW AERO 30 SSW RMY N/A TSTM
9/19 66/57/62/0/..../007/01         28 NE  AERO 25 NE  RMY 26
9/20 63/55/59/-3/..../110/15        22 NE  AERO 21 NE  RMY 19
9/21 70/55/63/+2/..../352/48        37 SSW AERO 37 SSW RMY 41
9/22 70/51/61/0/..../175/24         37 SW  AERO 36 SW  RMY 30
9/23 60/47/54/-6/..../058/08        14 N   AERO 13 N   RMY N/A 
9/24 55/50/53/-7/..../000/00        37 ENE AERO 35 ENE RMY 35
9/25 68/51/60/0/..../000/00         36 SE  AERO 37 SE  RMY 38
9/26 79/66/73/+14/..../244/34       35 SSW AERO 37 SSW RMY 37
9/27 66/56/61/+2/..../465/65        26 NNE AERO 25 NNE RMY 28
9/28 56/52/54/-4/..../029/04        24 NNE AERO 21 NNE RMY 23
9/29 71/50/61/+3/..../518/73        20 NW  AERO 18 NW  RMY 20
9/30 68/48/58/0/..../650/92         20 W   AERO 16 W   RMY N/A

DAILY RECORDS FOR SEPTEMBER

09/04/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 70F,
          BREAKS PREVIOUS RECORD OF 68F SET IN 1937 AND 1959

09/06/18: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 92F,
          TIES PREVIOUS RECORD OF 92F SET IN 1900 


PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 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

10/1 65/53/59/+2/..../.../..         21 ENE AERO 18 SSW RMY N/A
10/2 64/53/59/+2/..../.../..         33 S   AERO 32 S   RMY 35 TSTM
10/3 60/52/56/0/..../.../..          18 NNE AERO 14 NNE RMY 14
10/4 69/57/63/+7/..../.../..         29 SSW AERO 29 SSW RMY 32
10/5 64/47/56/0/..../.../..          25 NE  AERO 21 NE  RMY 24
10/6 64/45/55/0/0.00/.../..          23 SSW AERO 23 SSW RMY 25
10/7 75/56/66/+11/..../.../..        28 NE  AERO 24 ENE RMY 27
10/8 56/53/55/+1/..../.../..         22 ENE AERO 20 ENE RMY N/A
10/9 75/56/66/+12/..../.../..        26 WSW AERO 28 SW  RMY 29

10/10 Low temp since midnight is 65F; normal low is 45F

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

RECORDS FOR OCTOBER 10
HIGH 85F IN 1949
LOW 27F IN 1929
PRECIP 2.02 INCHES IN 1998
SNOWFALL 6.8 INCHES IN 1979 (RECORD FOR MONTH)
PEAK GUST 59 MPH WNW IN 1958

RECORDS FOR OCTOBER 11
HIGH 80F IN 1919,1949
LOW 28F IN 1993
PRECIP 0.96 INCHES IN 1903
SNOWFALL (NONE)
PEAK GUST 66e MPH WNW IN 1941

TODAY'S REPORT PREPARED BY: Nate Iannuccillo and Benjamin Turner