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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, OCTOBER 20, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

OVERCAST WITH LIGHT WINDS AND LIMITED VISIBILITY....

The sky has remained mostly cloudy today with a limited
visibility of 40 miles. This is due to a distant smoke 
layer from a subsidence inversion this morning. Conditions
have been dry, with dew points dropping to the mid 30's 
this afternoon. Wind is light and variable, with a
max gust so far around 10 mph.  

The high so far today is 59F, the same as the daily
normal maximum. While many towns throughout Massachusetts
had at or below freezing temperatures last night, the 
overnight low since midnight is only 43F atop Great Blue 
Hill. That is 2 degrees above the normal minimum of 41F. 

Today's Observations:

7 A.M.
Weather: Scattered altostratus, broken cirrus
Temperature: 47F; Dew Point: 40F; Wind: ENE at 8 kts
Sea-level pressure: 30.07 ins. Hg, rising then falling
Visibility: 50 miles, distant smoke layer
6-hr Max temp: 47F
6-hr Min temp: 43F
24-hour Precip.: 0.00 in. 
BHO SA 1155 180 SCT E250 BKN 50 184/47/40/0608/007/ K LYR 
ALG HRZN/ 8/012 53002 10047 20043

10 A.M.
Weather: Scattered altostratus, broken cirrus
Temperature: 53F; Dew Point: 43F; Wind: ESE at 3 kts,
Wind: Light and variable
Sea-level pressure: 30.11 ins. Hg, rising then more slowly 
Visibility: 40 miles, distant smoke layer
3-hour Precip.: 0.00 in.
BHO SA 1455 180 SCT E250 BKN 40 195/53/43/1103/011/ K LYR 
ALG HRZN WND L/V/ 8/012 51011 

1 P.M.
Weather: Scattered altostratus, broken cirrostratus,
few cumulus
Temperature: 58F; Dew Point: 36F; Wind: SW at 6 kts,
Wind: Light
Sea-level pressure: 30.09 ins. Hg, falling then more quickly
Visibility: 45 miles, distant smoke layer 
6-hr Max temp: 59F
6-hr Min temp: 47F 
BHO SA 1755 180 SCT E250 BKN 45 188/58/36/2306/009/ FEW CU ALQDS 
K LYR ALG HRZN WND LGT/ 8/118 58007 10059 20047


SUMMARY FOR SATURDAY, OCTOBER 19, 2019 

TEMPERATURE (DEGREES F)
MAX.....58   NORMAL.....59
MIN.....36   NORMAL.....42
MEAN....47   NORMAL.....50

DEPARTURE FROM 30-YEAR NORMAL.....................-3
TOTAL DEPARTURE FOR THE MONTH......................0 [ -0.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............18  DEPARTURE.........+3
TOTAL HEATING UNITS FOR THE MONTH..............217  DEPARTURE.........-4
TOTAL HEATING UNITS FOR THE SEASON.............310  DEPARTURE........-53
TOTAL HEATING UNITS LAST SEASON TO DATE........279  DEPARTURE........+31

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY................0  DEPARTURE..........0
TOTAL COOLING UNITS FOR THE MONTH................2  DEPARTURE.........-3
TOTAL COOLING UNITS FOR THE SEASON.............682  DEPARTURE........+80
TOTAL COOLING UNITS LAST SEASON TO DATE........874  DEPARTURE.......-192

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................18 NW  AT  9:04 A.M.  
                   AERO.........................18 NW  AT  9:46 A.M. 
                   ASOS.........................19 NW  AT  9:46 A.M.
                   DAVIS........................19 NW  AT  3:27 A.M. RMY 19
FASTEST MILE FOR YESTERDAY......................15 WNW AT  3:32 A.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE...................14 NW  AT  9:47 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..................15 WNW AT  9:46 A.M.
AVERAGE WIND SPEED AND DIRECTION...............8.7 W
                   ASOS........................8.5  
                   DAVIS.......................9.3 W [290 deg.]

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..........4.62  DEPARTURE......+1.79
                         ASOS..............4.88
TOTAL PRECIPITATION FOR THE YEAR..........43.04  DEPARTURE......+1.12
                         ASOS.............43.11


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  54/47/51/-3/..../.../..               41 NE  AERO 37 NE  RMY 42
10/11  52/48/50/-3/..../000/00               41 NE  AERO 39 NE  RMY 41
10/12  52/49/51/-2/..../.../..               39 NE  AERO 37 NE  RMY N/A
10/13  66/48/57/+4/..../.../..               18 WNW AERO 17 WNW RMY 18
10/14  67/51/59/+7/..../.../..               18 WSW AERO 17 WSW RMY N/A
10/15  61/43/52/0/..../.../..                18 NNW AERO 17 NNW RMY N/A
10/16  61/45/53/+2/..../.../..               58 ESE AERO 58 ESE RMY N/A
10/17  60/46/53/+2/..../.../..               61 E   AERO 63 E   RMY N/A
10/18  57/41/49/-2/..../.../..               29 WNW AERO 32 W   RMY 32
10/19  58/36/47/-3/..../.../..               18 NW  AERO 18 NW  RMY 19

10/20 The low since midnight is 43F, normal daily minimum is 41F


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

RECORDS FOR OCTOBER 20
HIGH 78F IN 1965,1984
LOW 24F IN 1972
PRECIP 7.10 INCHES IN 1996 (RECORD FOR MONTH)
SNOWFALL TRACE IN 1934,1943
PEAK GUST 63 MPH W IN 1966

RECORDS FOR OCTOBER 21
HIGH 79F IN 1979
LOW 24F IN 1974
PRECIP 2.39 INCHES IN 1944
SNOWFALL TRACE IN 1895,1907,1940
PEAK GUST 69e MPH S IN 1976

TODAY'S REPORT PREPARED BY: Benjamin Turner