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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, OCTOBER 10, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

LIGHT MORNING RAINFALL AND OVERCAST CONDITIONS,
YET SURPRISINGLY GOOD VISIBILITY TO THE NORTHWEST....

We observed a visibility of around 80 miles to the northwest, 
despite only 20 miles of visibility to the north, east, and 
south due to fog. This was most likely due to the abundant 
moisture offshore being pushed back by the dry and cold air
to the northwest. Rainfall overnight amounted to 0.26 inches,
and another 0.05 inches fell between 7 A.M. and 10 A.M. 
Wind has been strong and northerly, with frequent gusts above 
20 mph. The highest gust so far today is around 40 mph. 

The strong cold air advection, cloudy skies and rainfall have kept 
temperatures well below seasonal averages. The high so far today is 
50F, which is 12 degrees below the normal high of 62F. The low this 
morning was 47F, which is 2 degrees above the daily normal minimum 
of 45F. 

PRELIMINARY STATS FOR SEPTEMBER 2019

TEMPERATURE, Deg. F
Avg. Max. 73.6 [+2.0]
Avg. Min. 54.5 [-0.1]
Mean      64.1 [+1.0]
24-hour corrected mean: 63.4
Max. for month: 88F on the 23rd
Min. for month: 43F on the 19th

HEATING DEGREE DAYS
Total heating units:    81 [-36]
Total for the season:   93 [-49]
Total for last season:  87

COOLING DEGREE DAYS
Total cooling units:    58  [-2]
Total for the season:  680 [+83]
Total for last season: 863

PRECIPITATION, Inches
Total: 1.27 [-2.79]
Greatest in 24 hrs: 0.37 ins. on the 2nd 

WIND, mph
Avg. uncorrected wind speed: 10.3 mph
Avg. corrected wind speed:   10.9 mph
Prevailing wind direction:   SSW [11%]
Peak gust and direction:     39 W on the 2nd

SUNSHINE:
Campbell-Stokes card minutes: 14790 minutes of possible 21582 or 69%
Astronomical total minutes: 15399 minutes of possible 22468 or 69%

Today's Observations:

7 A.M.
Weather: Scattered stratus fractus, overcast nimbostratus,
light rain 
Temperature: 47F; Dew Point: 47F; Wind: N at 13G21 kts
Sea-level pressure: 30.27 ins. Hg, rising then steady 
Visibility: 80 miles, except 15 miles N-E due to fog
6-hr Max temp: 50F
6-hr Min temp: 47F
24-hr Precip: 0.26 ins.
BHO SA 1155 15 SCT E70 OVC 80R- 252/47/47/0113G21/027/ DSNT FG VSBY 15 
N-E R-CTD/ 8/72/ 70024 52003 10050 20047 

10 A.M.
Weather: Scattered stratus fractus, overcast nimbostratus, 
light rain
Temperature: 49F; Dew Point: 49F; Wind: N at 13G27 kts,
Peak wind: 38 MPH (32 kts) N at 9:22 A.M.
Sea-level pressure: 30.28 ins. Hg, rising, then rising more slowly
Visibility: 70 miles, except 20 miles N-SW due to a distant fog
3-hr Precip: 0.05 ins.
BHO SA 1455 15 SCT E70 OVC 70R- 256/49/49/0213G27/028/ DSNT FG VSBY 
20 N-SW R-CTD PK WND 0233/22/ 8/72/ 6005/ 51004

1 P.M.
Weather: Scattered stratus fractus, overcast altostratus
Temperature: 50F; Dew Point: 43F; Wind: N at 18G31 kts,
Peak wind: 39 MPH (34 kts) N at 11:04 A.M.
Sea-level pressure: 30.22 ins. Hg, falling, then falling more rapidly
Visibility: 80 miles due to fog, except 20 miles N-SW due to fog
6-hr Max temp: 50F
6-hr Min temp: 47F
6-hr Precip: 0.05 ins. 
BHO SA 1755 15 SCT E70 OVC 80 238/50/43/0218G31/022/ DSNT FG VSBY 20 
N-SW PK WND 0234/1604/ 8/72/ 6005/ 58018 10050 20047


SUMMARY FOR WEDNESDAY, OCTOBER 9, 2019 

TEMPERATURE (DEGREES F)
MAX.....55   NORMAL.....63
MIN.....49   NORMAL.....45
MEAN....52   NORMAL.....54

DEPARTURE FROM 30-YEAR NORMAL......................-2
TOTAL DEPARTURE FOR THE MONTH......................-2 [-0.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............13   DEPARTURE.........+2
TOTAL HEATING UNITS FOR THE MONTH..............89   DEPARTURE........ -1
TOTAL HEATING UNITS FOR THE SEASON............182   DEPARTURE........-49
TOTAL HEATING UNITS LAST SEASON TO DATE.......139   DEPARTURE........+43

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............0   DEPARTURE..........0
TOTAL COOLING UNITS FOR THE MONTH...............2   DEPARTURE.........-1
TOTAL COOLING UNITS FOR THE SEASON............682   DEPARTURE........+82
TOTAL COOLING UNITS LAST SEASON TO DATE.......865   DEPARTURE.......-183

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................43 NE   AT  7:49 P.M.
                   AERO.........................37 NE   AT  7:50 P.M.
                   ASOS.........................46 NE   AT  7:51 P.M.
                   DAVIS........................41 NE   AT  7:49 P.M. RMY 44
FASTEST MILE FOR YESTERDAY......................27 NE   AT  7:34 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE...................26 NE   AT  7:40 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..................29 NE   AT  7:39 P.M.
AVERAGE WIND SPEED AND DIRECTION................17.5 NE
                   ASOS.........................17.0 
                   DAVIS........................17.2 NE [54 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.26  DEPARTURE......+0.12
                         ASOS..............0.27
TOTAL PRECIPITATION FOR THE MONTH..........0.97  DEPARTURE......-0.36
                         ASOS..............0.96
TOTAL PRECIPITATION FOR THE YEAR..........39.39  DEPARTURE......-1.03
                         ASOS.............39.19

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  73/56/65/-3/0.00/703/89                21 ENE AERO 14 ENE RMY 18
9/02  75/57/66/-2/0.37/165/21                39 W   AERO 41 W   RMY 41
9/03  77/61/69/+2/0.00/643/82                18 S   AERO 16 S   RMY N/A
9/04  83/61/72/+5/0.00/375/48                30 SW  AERO 28 SW  RMY 30
9/05  68/54/61/-6/0.00/513/66                23 NW  AERO 17 NW  RMY N/A
9/06  65/56/61/-6/0.03/054/07                37 ENE AERO 36 ENE RMY 36
9/07  70/51/61/-5/0.27/325/42                37 N   AERO 37 N   RMY N/A
9/08  73/53/63/-3/0.00/631/82                25 W   AERO 21 W   RMY N/A
9/09  71/54/63/-3/0.00/537/70                17 SE  AERO 16 SE  RMY 16
9/10  73/57/65/0/0.00/207/27                 25 S   AERO 25 S   RMY N/A
9/11  83/63/73/+8/0.00/419/55                31 SW  AERO 32 SW  RMY N/A
9/12  70/52/61/-4/0.11/015/02                29 ENE AERO 28 ENE RMY 28
9/13  65/49/57/-7/0.00/741/98                29 ENE AERO 27 ENE RMY 27
9/14  69/49/59/-5/0.19/030/04                36 S   AERO 37 S   RMY 37
9/15  78/62/70/+6/0.00/600/80                24 W   AERO 23 W   RMY 22
9/16  72/54/63/0/T/673/90                    25 WNW AERO 23 WNW RMY 25
9/17  67/49/58/-5/0.00/611/82                23 NW  AERO 23 N   RMY N/A
9/18  61/49/55/-7/0.00/579/78                26 NE  AERO 25 NE  RMY 25
9/19  67/43/55/-7/0.00/709/96                17 NE  AERO 18 NE  RMY N/A
9/20  78/50/64/+2/0.00/677/92                21 W   AERO 18 W   RMY 20
9/21  83/60/72/+11/0.00/689/94               21 WNW AERO 18 WNW RMY N/A
9/22  85/62/74/+13/0.00/687/94               24 SW  AERO 23 SW  RMY 25
9/23  88/65/77/+17/0.00/539/74               29 SSW AERO 28 SSW RMY 29
9/24  76/56/66/+6/0.04/616/85                26 W   AERO 26 W   RMY 27  
9/25  73/50/62/+2/0.00/686/95                22 W   AERO 21 W   RMY 21
9/26  79/55/67/+8/0.25/388/54                38 SW  AERO 37 SW  RMY 39
9/27  72/50/61/+2/0.00/695/97                23 S   AERO 23 S   RMY 22
9/28  78/55/67/+9/0.00/664/93                31 S   AERO 29 S   RMY 30
9/29  75/53/64/+6/0.00/619/87                24 NW  AERO 23 NW  RMY 23
9/30  62/49/56/-2/0.00/609/86                23 NNE AERO 16 NNE RMY N/A


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

10/01  67/52/60/+3/0.06/.../..               28 SW  AERO 25 SSW RMY 29
10/02  74/49/62/+5/0.42/.../..               30 ENE AERO 25 ENE RMY 28
10/03  51/46/49/-7/..../.../..               28 ENE AERO 26 ENE RMY N/A
10/04  59/40/50/-6/..../.../..               38 NNW AERO 38 NNW RMY 38
10/05  58/35/47/-9/0.00/.../..               21 N   AERO 18 SSW RMY N/A
10/06  65/44/55/0/0.00/.../..                36 SSW AERO 35 SSW RMY N/A
10/07  77/57/67/+12/0.12/.../..              47 SSW AERO 46 SSW RMY 49
10/08  60/52/56/+2/T/.../..                  22 NE  AERO 18 NW  RMY N/A
10/09  55/49/52/-2/..../.../..               43 NE  AERO 37 NE  RMY 44

10/10  The low since midnight is 47F, normal daily minimum 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: Benjamin Turner