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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, OCTOBER 7, 2015 
ALL TIMES ARE IN EASTERN STANDARD TIME

CLEAR, SEASONABLE CONDITIONS PREVAIL TUESDAY, WARM UP
ON TAP FOR TODAY

After a seasonable day yesterday, which featured highs in the
upper 60s and an overnight low of 46F, sunny skies and warm
temperatures were in place today. High dense cirrus were quick
to give way to blue skies and small fair weather cumulus by mid
morning, with temperatures warming through the 60s.

By the 1:00 PM EST observation conditions were largely the same
as the 10:00 AM EST observation, with mostly clear skies and only
a few distant cirrus offshore and small cumulus inland from the 
station. A maximum temperature of 68F had been reached.
  

SEPTEMBER Details below:

BHO Warmest Septembers (NWS mean), deg F (1885-2015):

1) 68.2 in 2015
2) 66.9 in 1961
3) 66.5 in 1930
4) 66.4 in 1999
5) 66.2 in 2002
   66.2 in 2005

BHO Warmest September Average Maximum Temperature, deg F (1885-2015):

1) 77.8 in 2015
2) 76.6 in 1930
3) 75.7 in 2007
4) 75.6 in 1959
5) 75.5 in 1961

BHO Warmest September Average Minimum Temperature, deg F (1885-2015):

1) 58.8 in 1988
2) 58.5 in 2015
3) 58.2 in 1961
   58.2 in 1999
5) 57.8 in 2005

BHO Warmest Aug-Sep (24-hour adjusted mean), deg F (1885-2015):

1) 69.8 in 2015
2) 68.9 in 2005
3) 68.6 in 2002
4) 68.2 in 2010
5) 67.8 in 1959 

BHO Slowest September Mean Wind Speed, mph (1885-2015):

1) 10.3 in 2015
2) 10.5 in 2014
3) 10.6 in 2013
4) 10.7 in 2011
5) 10.9 in 1917
   10.9 in 2003

BHO Sunniest Septembers, hours (1885-2015):

1) 267.7 in 1983  [74%]
2) 266.9 in 1941  [74%]
3) 265.9 in 2007  [74%]
4) 255.3 in 1948  [71%]
5) 251.9 in 2015  [70%]
6) 251.0 in 1967  [70%]
7) 246.8 in 1952  [69%]
   246.8 in 1978  [69%]

BHO Sunniest Aug-Sep, hours (1885-2015):

1) 555.1 in 2015  [72%]
2) 553.0 in 1941  [72%]
3) 536.0 in 2007  [69%]
4) 527.3 in 2014  [68%]
5) 520.2 in 1932  [67%]
6) 515.3 in 1921  [67%]
7) 514.3 in 1968  [67%]


PRELIMINARY STATS FOR SEPTEMBER 2015

TEMPERATURE, Deg. F
Avg. Max. 77.8 [+6.2]
Avg. Min. 58.5 [+3.9]
Mean      68.2 [+5.1]
Corrected mean: 67.3
Max. for month: 97 on 8th
Min. for month: 46 on 27th

COOLING DEGREE DAYS
Total cooling units: 144 [+84]  
Total for the season: 810 [+213]
Total for last season: 587

HEATING DEGREE DAYS
Total heating units: 42 [-75]  
Total for the season: 43 [-99]
Total for last season: 101

PRECIPITATION, Inches
Total: 3.88 [-0.18]
Greatest in 24 hrs: 2.53 inches from 9/29-30
 
WIND, mph
Avg. uncorrected wind speed: 10.1
Avg. corrected wind speed: 10.3
Prevailing wind direction: SSW @ 13%
Peak gust and direction: 47 S on the 30th

SUNSHINE:
Campbell-Stokes card minutes: 15114 mins. of possible 21582 or 70%
Astronomical total minutes:   15766 mins. of possible 22472 or 70%

Today's Observations:

7 A.M.
Weather: Scattered dense cirrus
Temperature: 50F; Dew Point: 46F; Wind: WNW at 7 kts,
Sea-level pressure: 29.98 ins. Hg, rising, then more quickly
Visibility:  70 miles, except 40 miles SW-W, thin fog distant SW-W 
6-hr Max temp: 50F  
6-hr Min temp: 46F
24-hr precip: 0.00 ins. 
BHO SA 1155 250 SCT 70 152/50/46/3007/998/ VSBY SW-W 40 MI THN FG 
DSNT SW-W/ 8/002 53008 10050 20046 

10 A.M.
Weather: Clear, few small cumulus distant ESE-NNE, few altocumulus
distant W-NW, few dense cirrus distant E-SW
Temperature: 63F; Dew Point 50F; Wind: NNW at 8 kts, 
Sea-level pressure: 29.98 ins. Hg, rising, then falling but higher still
Visibility: 75 miles 
BHO SA 1455 CLR 75 151/63/50/3308/998/ FEW SML CU DSNT ESE-NNE FEW AC 
DSNT W-NW FEW CI DSNT E-SW/ 8/132 50001
 
1 P.M.
Weather: Clear, few small cumulus WSW-NNE, few cirrus 
distant ESE-S
Temperature: 68F; Dew Point: 49F; Wind: WNW  at 8 kts
Sea-level pressure: 29.94 ins. Hg, decreasing then more rapidly 
Visibility: 70 miles, light distant haze   
6-hr Max: 68F 
6-hr Min: 50F
6-hr precip: none  
BHO SA 1755 CLR 70 140/68/49/3008/994/ FEW SML CU WSW-NNE 
FEW CI DSNT ESE-S LGT DSNT HZ ALQDS/ 8/101 58011 10068 20050


SUMMARY FOR TUESDAY, OCTOBER 6, 2015 
  
TEMPERATURE (DEGREES F)
MAX.....68   NORMAL.....64 
MIN.....43   NORMAL.....47 
MEAN....56   NORMAL.....55 
 
DEPARTURE FROM 30-YEAR NORMAL........................+1
TOTAL DEPARTURE FOR THE MONTH.......................-26  [-4.5 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..........-2
TOTAL COOLING UNITS FOR THE SEASON............810   DEPARTURE........+211
TOTAL COOLING UNITS LAST SEASON TO DATE.......587   DIFFERENCE.......+223

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............9   DEPARTURE..........-1
TOTAL HEATING UNITS FOR THE MONTH..............79   DEPARTURE.........+23
TOTAL HEATING UNITS FOR THE SEASON............122   DEPARTURE.........-76
TOTAL HEATING UNITS LAST SEASON TO DATE.......169   DIFFERENCE........-47
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY...................17  NW  AT  1:53 P.M. 
                   ASOS........................17  NNW AT 11:10 P.M.  
                   DAVIS.......................15  NW  AT  1:48 P.M. RMY 17
FASTEST MILE FOR YESTERDAY.................... 13  N   AT  5:58 A.M.*  
MAXIMUM 2-MINUTE ASOS AVERAGE..................14  N   AT  6:00 A.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE.................12  N   AT  5:59 A.M.  
AVERAGE WIND SPEED AND DIRECTION..............6.7 N 
                   ASOS.......................7.0    
                   DAVIS..................... 5.8 N [007 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...........0.52  DEPARTURE.....-0.37
                         ASOS...............0.50
TOTAL PRECIPITATION FOR THE YEAR...........34.19  DEPARTURE.....-5.31
                         ASOS................N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER & OCTOBER CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY 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

9/1  81/65/73/+5/0.00/766/97               20 SSW RMY 20
9/2  89/64/77/+9/0.00/732/93               20 SW  RMY 21  
9/3  85/66/76/+9/T/612/78                  17 E   RMY N/A TSTM 
9/4  72/58/65/-2/0.00/297/38               31 ENE RMY N/A
9/5  77/55/66/-1/0.00/748/96               14 SW  RMY 18
9/6  87/57/72/+5/0.00/753/97               21 SSW RMY 22
9/7  92/63/78/+12/0.00/727/94              23 WSW RMY 24
9/8  97/70/84/+18/0.00/693/90              22 WSW RMY 24
9/9  92/70/81/+15/0.00/683/89              30 SSW RMY 33
9/10 73/62/68/+3/0.32/000/00               29 NE  RMY N/A
9/11 70/59/65/0/0.59/084/11                33 NE  RMY N/A
9/12 75/58/67/2/0.02/380/50                18 SSE RMY 25 
9/13 66/60/63/-1/0.42/000/00               25 E   RMY N/A
9/14 70/53/62/-2/0.00/550/73               33 W   RMY 35
9/15 82/56/69/+5/0.00/736/98               23 W   RMY N/A
9/16 84/62/73/+10/0.00/711/95              17 NW  RMY N/A
9/17 87/64/76/+13/0.00/723/97              17 SW  RMY 16
9/18 86/64/75/+13/0.00/712/96              21 SSW RMY 21
9/19 80/62/71/+9/0.00/480/65               22 S   RMY N/A
9/20 74/55/65/+3/T/552/75                  24 S   RMY N/A  
9/21 65/50/58/-3/0.00/646/88               29 ENE RMY 30
9/22 67/55/61/+0/0.00/183/25               21 E   RMY 21
9/23 72/50/61/+1/0.00/677/93               15 E   RMY N/A
9/24 72/56/64/+4/0.00/696/96               22 E   RMY 21   
9/25 66/53/60/0/0.00/556/77                21 E   RMY 20 
9/26 63/49/56/-3/0.00/633/88               25 ENE RMY 25
9/27 71/46/59/+0/0.00/688/96               17 S   RMY 18
9/28 81/57/69/+11/0.00/428/60              22 SSW RMY 24
9/29 82/65/74/+16/..../320/45              28 S   RMY N/A
9/30 75/53/64/+6/..../000/00               47 S   RMY 51  TSTM

10/1 55/51/53/-4/..../.../..               39 NE  RMY N/A
10/2 51/47/49/-8/..../.../..               40 NE  RMY 43 
10/3 51/45/48/-8/..../000/00               38 NE  RMY N/A 
10/4 55/49/52/-4/0.00/.../..               35 E   RMY 40
10/5 59/46/53/-3/T/.../..                  21 NE  RMY 20 
10/6 68/43/56/+1/0.00/.../..               17 NW  RMY 17

10/7 low since midnight is 46F; normal low is now 46F  

DAILY RECORDS FOR SEPTEMBER & OCTOBER 2015

**9/7 DAILY RECORD MAXIMUM TEMPERATURE OF 92F 
TIES PREVIOUS RECORD SET IN 2007**

**9/8 DAILY RECORD MAXIMUM TEMPERATURE OF 97F
BREAKS PREVIOUS RECORD OF 93F SET IN 2007**

**9/8 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 70F
BREAKS PREVIOUS RECORD OF 69F SET IN 1999**

**9/9 DAILY RECORD MAXIMUM TEMPERATURE OF 92F
BREAKS PREVIOUS RECORD OF 91F SET IN 2002**

**9/9 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 70F
BREAKS PREVIOUS RECORD OF 69F SET IN 1999**

**9/17 DAILY RECORD MAXIMUM TEMPERATURE OF 87F
BREAKS PREVIOUS RECORD OF 86F SET IN 1915, 1941, AND 1991**

**9/18 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 64F
TIES PREVIOUS RECORD SET IN 1992**

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

RECORDS FOR OCTOBER 7
HIGH 88F IN 1963 (RECORD FOR MONTH)
LOW 30F IN 1904,1986
PRECIP 1.75 INCHES IN 1972
PEAK GUST 54 W IN 2009

RECORDS FOR OCTOBER 8
HIGH 81F IN 1916,1990
LOW 28F IN 1919
PRECIP 2.31 INCHES IN 1891
SNOWFALL TRACE IN 1988, 2001 (EARLIEST DATE)
PEAK GUST 60 MPH NE IN 1996

TODAY'S REPORT PREPARED BY: Brian Fitzgerald