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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, OCTOBER 19, 2017  
ALL TIMES ARE IN EASTERN STANDARD TIME

DRY, WARM, AND PLEASANT CONDITIONS CONTINUE

With high pressure in the area clear and dry conditions 
continue. The sky remained mostly clear with few to scattered 
cirrus clouds at each observation. The day started with a 
partial undercast layer NNE-SE. This undercast layer obstructed 
visibility to an 1/8 mile NNE-SE and 45 miles SE-NNE at the 
7:00 AM EST observation. A distant haze kept visibility at 
45 miles during the 10:00 AM EST observation, but visibility 
increased to 70 miles by 1:00 PM EST. Temperatures continue 
to be above seasonable with a high of 71F by 1:00 PM EST. 
This is 11 degrees above the normal of 60F for this day. 
Winds from the SSW picked up later in the morning with gust 
up to 28 MPH. 
 
Today's Observations:

7 A.M.
Weather: Clear, few cirrus S-NNE, partial undercast layer
NNE-SE and patches of ground fog below the summit S-NNE
Temperature: 53F; Dew Point: 51F; Wind: SSW at 9 kts
Sea-level pressure: 30.24 ins. Hg, falling then rising
Visibility: 45 miles S-NNE, 1/8 miles NNE-S, distant fog
S-NNE
6-hr Max temp: 55F
6-hr Min temp: 52F
24-hr precip: 0.00 ins. 
BHO SA 1155 CLR 45 241/53/51/2009/024/ FEW CI S-NNE VSBY 
NNE-S 1/8 PARTIAL UNDERCAST NNE-SE PTCHS GF BLO SMT S-NNE 
DSNT FG S-NNE/ 8/001 55003 10055 20052

10 A.M.
Weather: Scattered cirrus 
Temperature: 59F; Dew Point: 52F; Wind: SSW at 12G20 kts
Sea-level pressure: 30.21 ins. Hg, falling, then more quickly
Visibility: 45 miles distant haze in all directions 
BHO SA 1455 300 SCT 45 232/59/52/2012G20/021/ DSNT HZ ALQDS/ 
8/001 58009

1 P.M. 
Weather: Clear, few cirrus in all directions 
Temperature: 70F; Dew Point: 45F; Wind: SSW at 17G24 kts
Sea-level pressure: 30.12 ins. Hg, falling, then more quickly
Visibility: 70 miles  
6-hr Max temp: 71F 
6-hr Min temp: 53F
BHO SA 1755 CLR 70 199/70/45/2017G24/012/ FEW CI ALQDS/ 8/001 
58033 10071 20053

SUMMARY FOR WEDNESDAY, OCTOBER 18, 2017
 
TEMPERATURE (DEGREES F)
MAX.....70   NORMAL.....60
MIN.....45   NORMAL.....42
MEAN....58   NORMAL.....51

DEPARTURE FROM 30-YEAR NORMAL.........................+7
TOTAL DEPARTURE FOR THE MONTH.......................+125 [+6.7 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............0   DEPARTURE...........0
TOTAL COOLING UNITS FOR THE MONTH..............20   DEPARTURE.........+16
TOTAL COOLING UNITS FOR THE SEASON............727   DEPARTURE........+126
TOTAL COOLING UNITS LAST SEASON TO DATE.......894   DEPARTURE........-167

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............7   DEPARTURE..........-7
TOTAL HEATING UNITS FOR THE MONTH..............95   DEPARTURE........-111
TOTAL HEATING UNITS FOR THE SEASON............188   DEPARTURE........-160
TOTAL HEATING UNITS LAST SEASON TO DATE.......223   DEPARTURE.........-35

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................25  SW  AT 1:05 A.M. 
                   AERO........................23  SW  AT 1:04 A.M.
                   ASOS........................26  SW  AT 1:04 A.M.
                   DAVIS.......................25  SW  AT 1:06 A.M.   RMY 25 
FASTEST MILE FOR YESTERDAY.....................19  SW  AT 1:09 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................20  SW  AT 1:06 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE.................18  SW  AT 1:08 A.M.
AVERAGE WIND SPEED AND DIRECTION.............10.1  SW
                   ASOS.......................9.9
                   DAVIS......................9.8  WSW [254 DEG.]

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..........0.50  DEPARTURE......-2.18
                         ASOS..............0.50
TOTAL PRECIPITATION FOR THE YEAR..........42.36  DEPARTURE......+0.60
                         ASOS...............N/A ***
*** ASOS annual total not available due to erroneous readings


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  65/42/54/-3/0.00/697/99               18 WNW AERO 16 NW  RMY N/A
10/2  65/46/56/-1/0.00/687/98               21 NNW AERO 21 NNW RMY 21
10/3  67/50/59/+3/0.00/677/97               21 S   AERO 21 S   RMY N/A
10/4  75/50/63/+7/0.00/660/95               30 SSW AERO 30 SW  RMY 32
10/5  79/60/70/+14/0.00/.../..              28 SW  AERO 26 SW  RMY N/A
10/6  73/57/65/+10/T/.../..                 15 NW  AERO 14 NW  RMY 15
10/7  75/59/67/+12/T/.../..                 29 S   AERO 30 SSW RMY N/A
10/8  71/67/69/+15/0.23/.../..              33 S   AERO 36 SSW RMY 37
10/9  71/68/70/+16/0.22/.../..              43 S   AERO 41 S   RMY 45
10/10 76/61/69/+15/0.00/.../..              21 WNW AERO 20 WNW RMY 21 
10/11 68/55/62/+9/0.00/.../..               29 ENE AERO 25 ENE RMY 29 
10/12 58/48/50/0/T/.../..                   30 NE  AERO 28 ENE RMY 30 
10/13 64/48/56/+3/0.00/.../..               20 E   AERO 16 E   RMY 17
10/14 66/54/60/+8/.../.../..                15 SSE AERO 13 SSE RMY 13 
10/15 72/58/65/+13/.../.../..               39 SSW AERO 36 SSW RMY 40 
10/16 66/39/53/+2/.../.../..                28 NNW AERO 25 NNW RMY 29
10/17 57/35/46/-5/0.00/.../..               25 S   AERO 22 S   RMY 25
10/18 70/45/58/+7/0.00/../..                25 SW  AERO 23 SW  RMY 22 

10/19 Low temp since midnight is 52F; normal low is now 42F

DAILY RECORDS FOR OCTOBER

10/8/17: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
         BREAKS PREVIOUS RECORD OF 60F SET IN 1944

10/9/17: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 68F,
         BREAKS PREVIOUS RECORD OF 61F SET IN 2011

10/9/17: MONTHLY RECORD HIGH MINIMUM TEMPERATURE OF 68F,
         BREAKS PREVIOUS RECORD OF 67F SET ON OCTOBER 13, 1990
         AND TIED ON OCTOBER 8, 2017

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

RECORDS FOR OCTOBER 19
HIGH 81F IN 1945
LOW  21F IN 1922
PRECIP 3.64 INCHES IN 1932
SNOWFALL 1.0 INCHES IN 1972
PEAK GUST 66 MPH SSW IN 1967

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

TODAY'S REPORT PREPARED BY: Kaitlin Geagan