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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, OCTOBER 3, 2017  
ALL TIMES ARE IN EASTERN STANDARD TIME

SEASONABLE FALL WEATHER CONTINUE AS HIGH PRESSURE SITS OVER REGION

Clear skies and mild temperatures continue at Great Blue Hill.
Skies had a mix of few cumulus and few cirrus for most of the
late morning and early afternoon.  Temperatures were slightly
warmer this morning with an overnight low of 50F and then rose
to a max. of 66F by 1:00PM.  Visibility was 50 miles at the
7:00AM observation due to dissipating fog in the region but
improved to 70 miles for the remainder of the day.  Winds had
become southwesterly in the afternoon which is set to bring very
warm temperatures for tomorrow.


PRELIMINARY STATS FOR SEPTEMBER 2017
 
TEMPERATURE, Deg. F
Avg. Max. 74.5 [+2.9]
Avg. Min. 57.3 [+2.7]
Mean      65.9 [+2.8]
24-hour corrected mean: 65.1
Max. for month: 86F on 25th and 27th
Min. for month: 44F on 30th
 
HEATING DEGREE DAYS
Total heating units: 67 [-50]
Total for the season: 93 [-49]
Total for last season: 75

COOLING DEGREE DAYS
Total cooling units: 100 [+40]
Total for the season: 707 [+110]
Total for last season: 894

PRECIPITATION, Inches
Total: 5.50 [+1.44]
Greatest in 24 hrs: 2.33 on the 30th

WIND, mph
Avg. uncorrected wind speed: 10.2
Avg. corrected wind speed: 10.8
Prevailing wind direction: NNE at 13%
Peak gust and direction: 47 NNE on 21st
 
SUNSHINE:
Campbell-Stokes card minutes: N/A
Astronomical total minutes: N/A


Today's Observations:

7 A.M.
Weather: Few distant cumulus N, few altostratus N-NE, few cirrus
in all directions, patches of ground fog below the summit ESE-SW
and NW, temperature inversion present to the SW with an estimated
top of 300 feet
Temperature: 54F; Dew Point: 46F; Wind: SE at 5 kts,
Wind speed: Light
Sea-level pressure: 30.65 ins. Hg, rising, then more slowly
Visibility: 50 miles, distant fog in all directions
6-hr Max temp: 54F
6-hr Min temp: 50F
24-hr precip: 0.00 in.
BHO SA 1155 CLR 50 380/54/46/1305/065/ FEW CU DSNT N FEW AS N-NE
FEW CI ALQDS PTCHS GF BLO SMT ESE-SW AND NW DSNT FG ALQDS
INVSN PRSNT ESTMTD TOP 3 HND SW WND LGT/ 8/111 51018 10054 20050

10 A.M.
Weather: Few cumulus in all directions, few cirrus N-S
Temperature: 61F; Dew Point: 44F; Wind: estimated SSE at 3 kts,
Wind: Light and variable
Sea-level pressure: 30.68 ins. Hg, rising, then more quickly
Visibility: 70 miles
BHO SA 1455 CLR 70 391/61/44/E1603/068/ FEW CU ALQDS FEW CI N-S
WND L/V/ 8/101 53011

1 P.M. 
Weather: Few cumulus in all directions, few cirrus in all directions
Temperature: 66F; Dew Point: 46F; Wind: S at 4 kts,
Wind: Light and variable
Sea-level pressure: 30.63 ins. Hg, falling, then more quickly
Visibility: 70 miles
6-hr Max temp: 66F 
6-hr Min temp: 54F
BHO SA 1755 CLR 70 373/66/46/1904/063/ FEW CU ALQDS FEW CI ALQDS
WND L/V/ 8/101 58018 10066 20054


SUMMARY FOR MONDAY, OCTOBER 2, 2017
 
TEMPERATURE (DEGREES F)
MAX.....65   NORMAL.....66
MIN.....46   NORMAL.....48
MEAN....56   NORMAL.....57

DEPARTURE FROM 30-YEAR NORMAL.........................-1
TOTAL DEPARTURE FOR THE MONTH.........................-4 [-2.2 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............0   DEPARTURE...........0
TOTAL COOLING UNITS FOR THE MONTH...............0   DEPARTURE..........-1
TOTAL COOLING UNITS FOR THE SEASON............707   DEPARTURE........+109
TOTAL COOLING UNITS LAST SEASON TO DATE.......894   DEPARTURE........-187

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............9   DEPARTURE...........0
TOTAL HEATING UNITS FOR THE MONTH..............20   DEPARTURE..........+3
TOTAL HEATING UNITS FOR THE SEASON............113   DEPARTURE.........-46
TOTAL HEATING UNITS LAST SEASON TO DATE........96   DEPARTURE.........+17

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................21 NNW AT 3:00 A.M.
                   AERO........................21 NNW AT 3:01 A.M.
                   ASOS........................22 NNW AT 3:01 A.M.
                   DAVIS.......................19 NNW AT 3:00 A.M. RMY 21
FASTEST MILE FOR YESTERDAY.....................16 NNW AT 3:00 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................16 NNW AT 3:02 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE.................14 NNW AT 3:01 A.M.
AVERAGE WIND SPEED AND DIRECTION..............9.2 NNW
                   ASOS.......................9.0
                   DAVIS......................7.9 N [012 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..........0.00  DEPARTURE......-0.31
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE YEAR..........41.86  DEPARTURE......+2.47
                         ASOS...............N/A ***
*** ASOS annual total not available due to erroneous readings


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

9/1  68/47/58/-10/0.00/749/95              26 WNW AERO 28 WNW RMY 31
9/2  72/46/59/-9/0.00/542/69               18 NNW AERO 18 NNW RMY 21
9/3  63/52/58/-9/0.24/000/00               33 W   AERO 33 W   RMY 37
9/4  79/55/67/0/0.00/702/90                29 SSW AERO 28 SSW RMY N/A
9/5  84/62/73/+6/0.00/583/75               36 S   AERO 32 S   RMY 38
9/6  76/59/68/+1/0.49/070/09               28 S   AERO 28 S   RMY 30 TSTM
9/7  74/58/66/0/0.79/417/54                24*WSW AERO 23 WSW RMY 24 
9/8  74/53/64/-2/0.00/577/75               21 WSW AERO 18 WSW RMY 22
9/9  68/51/60/-6/T/620/81                  18 ENE AERO 16 ENE RMY 18
9/10 71/51/61/-4/0.00/694/91               18 NW  AERO 16 NW  RMY N/A
9/11 78/50/64/-1/0.00/692/91               20 NNW AERO 17 NNW RMY 20
9/12 84/58/71/+6/0.00/690/91               22 WSW AERO 18 WSW RMY 23
9/13 84/59/72/+8/T/680/90                  18 WSW AERO 15 WSW RMY 20 TSTM
9/14 82/66/74/+10/0.00/233/31              23 SW  AERO 23 WSW RMY 25 TSTM
9/15 83/66/75/+11/0.05/300/40              18 WNW AERO 15 WNW RMY 18
9/16 78/65/72/+9/T/261/35                  14 E   AERO  9 E   RMY 12
9/17 79/61/70/+7/T/334/45                  15 SSE AERO 14 SSE RMY 15
9/18 67/62/65/+3/0.02/000/00               21 NE  AERO 18 NE  RMY N/A
9/19 63/61/62/0/0.13/000/00                28 NE* AERO 25 NNE RMY N/A
9/20 68/62/65/+3/0.67/000/00               41 NNE AERO 44 NNE RMY 45
9/21 69/60/65/+4/0.01/242/33               47 NNE AERO 44 NNE RMY 50
9/22 60/54/57/-4/0.56/000/00               40 NNE AERO 38 NNE RMY N/A
9/23 74/59/67/+7/0.21/421/58               29 NNE AERO 29 NNE RMY N/A
9/24 85/63/74/+14/0.00/688/95              16 N   AERO 14 N*  RMY N/A
9/25 86/66/76/+16/0.00/671/93              15 ESE*AERO 13 ESE RMY 14
9/26 84/66/75/+16/0.00/503/70              15 SW  AERO 12 SW* RMY 14
9/27 86/64/75/+16/0.00/551/77              21 S   AERO 20 S   RMY 22 
9/28 75/52/64/+6/0.00/605/85               29 NNW AERO 30 NNW RMY 33
9/29 65/46/56/-2/0.00/.../..               21 NNW AERO 20 NNW RMY N/A
9/30 56/44/50/-8/2.33/000/00               28 NE  AERO 25 ENE RMY 27 TSTM

DAILY RECORDS FOR SEPTEMBER

9/1/17: DAILY RECORD LOW MINIMUM TEMPERATURE OF 47F,
        TIES PREVIOUS RECORD SET IN 1975

9/27/17: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 86F, 
         BREAKS PREVIOUS RECORD SET IN 1998 AND TIED IN 2014

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/.../..               18 WNW AERO 16 NW  RMY N/A
10/2  65/46/56/-1/0.00/.../..               21 NNW AERO 21 NNW RMY 21

10/3 Low temp since midnight is 50F; normal low is now 48F

DAILY RECORDS FOR OCTOBER

None so far.


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

RECORDS FOR OCTOBER 3
HIGH 82F IN 1922
LOW 28F IN 1899
PRECIP 1.76 INCHES IN 1979
PEAK GUST 62 MPH WNW IN 1964

RECORDS FOR OCTOBER 4
HIGH 84F IN 2007 
LOW 28F IN 1888
PRECIP 1.87 INCHES IN 2011
PEAK GUST 59 MPH SSW IN 1990

TODAY'S REPORT PREPARED BY: Cecilia Borries-Strigle