BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, SEPTEMBER 25, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME
 
YET ANOTHER FINE FALL WEATHER DAY AS HIGH PRESSURE
CENTERED OVER THE GREAT LAKES REGION BRINGS A
CONTINUATION OF VERY FINE LATE SEPTEMBER WEATHER 
WHICH WILL BE EXTENDING INTO THE COMING WEEKEND 
 
Today becomes the third consecutive day with plenty of
bright sunshine, excellent visibility of 80 to 90 miles
in the dry air.  Temperatures continue to run more than
several degrees cooler than normal.  Monday and Tuesday
both averaged 7 degrees cooler than average and this
morning's low of 45F is six degrees below the normal
minimum to be expected for this date.  September was
averaging one degree cooler than normal through the 24th.
 
The extended forecast is for more of the same beautiful
sunny, dry but slightly milder weather late September
weather in the final days of the month.
 
Today's Observations:
 
7 A.M.  
Weather:  Clear, few cumulus, moderate cumulus offshore distant NE,
few stratocumulus along horizon distant NNW-NE-ESE
Temperature: 50F; Dew Point: 44F; Wind: NW at 8 kts.
Sea-level pressure: 29.89 ins. Hg, falling then rising slightly
Visibility: 80 miles
6-hr min. temp: 45F
BHO SA 1155 CLR 80 123/50/44/3108/989/ FEW CU/MDT OFFSHR DSNT
NE FEW SC DSNT NNW-ESE LGT DSNT HZ / 8/800 55000 10050 20045
 
10 A.M. 
Weather: Clear, small cumulus fractus, cumulus forming all quadrants,
few altocumulus/altocumulus lenticularis distant NNW-E  
Temperature: 60F; Dew Point: 45F; Wind: N at 9 kts,
Wind: Direction variable NW-NE 
Sea-level pressure: 29.93 ins. Hg, rising then more slowly 
Visibility: 80 miles, light distant haze
BHO SA 1455 CLR 80 134/60/45/3609/993/ SML CUFRA/CU FRMG ALQDS
AC/ACSL DSNT NNW-E WND 32V04/ 8/840 51011
 
1 P.M. 
Weather: Scattered cumulus, stratocumulus cumulogenitus all quadrants,
scattered altocumulus, altocumulus lenticularis, altocumulus/
altocumulus lenticularis distant NNE-ESE 
Temperature: 64F; Dew Point: 48F; Wind: N at 4 kts,
Wind: Light
Sea-level pressure: 29.91 ins. Hg, falling slightly
Visibility: 80 miles, light distant haze
6-hr max. temp: 64F
BHO SA 1755 50 SCT 100 SCT 80 129/64/48/0104/991/ CU/SCCU ALQDS
AC/ACSL DSNT NNE-ESE LGT DSNT HZ WND LGT/ 8/440 58005 10064 20050
 
WEATHER SUMMARY FOR TUESDAY, SEPTEMBER 24, 2013
 
TEMPERATURE (DEGREES F)
MAX.....65    NORMAL.....69
MIN.....40    NORMAL.....52
MEAN....53    NORMAL.....60
 
DEPARTURE FROM 30-YEAR NORMAL.....................-7
TOTAL DEPARTURE FOR THE MONTH....................-20 [-1.0 DEGREE/DAY]
 
COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY..............0   DEPARTURE.........-1
TOTAL COOLING UNITS FOR THE MONTH.............56   DEPARTURE.........+1
TOTAL COOLING UNITS FOR THE SEASON...........696   DEPARTURE.......+104
TOTAL COOLING UNITS LAST SEASON TO DATE......765   DIFFERENCE.......-69
 
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............12   DEPARTURE.........+6
TOTAL HEATING UNITS FOR THE MONTH.............93   DEPARTURE........+13
TOTAL HEATING UNITS FOR THE SEASON...........105   DEPARTURE.........+6
TOTAL HEATING UNITS LAST SEASON TO DATE.......58   DIFFERENCE.......+47
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY..................22 ENE AT  6:34 P.M *
                   AERO.......................22 N   AT  5:17 P.M.
                   ASOS.......................23 ENE AT  6:34 P.M.
                   DAVIS......................22 WNW AT 11:23 A,N, RMY 23
FASTEST MILE FOR YESTERDAY....................14 ENE AT  6:36 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE.................16 ENE AT  6:35 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE................15 NE  AT  6:35 P.M.
AVERAGE WIND SPEED AND DIRECTION............ 9.8 WNW
                   ASOS......................9.3
                   DAVIS.....................8.6 NW  [310 degrees]
* last of several occurrences...
 
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..........3.91   DEPARTURE.............+0.73
                         ASOS..............4.04
TOTAL PRECIPITATION FOR THE YEAR..........41.92   DEPARTURE.............+3.72
                         ASOS..............N/A*
*ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals 
     
PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 2013 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane wind recording system gust
RMY:  RMY = R.M. Young wind gust recording system added 8/9/2011
TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized
 
9/1  76/67/72/+4/2.32/008/01         33 S   AERO 39 MPH S   RMY 38   TSTM
9/2  79/67/73/+5/0.43/056/07         30 SSE AERO 33 MPH SSE RMY N/A  TSTM
9/3  79/61/70/+3/0.00/219/28         28 S   AERO 29 MPH S   RMY 30   TSTM
9/4  78/57/68/+1/0.00/733/94         24 W   AERO 25 MPH W   RMY 25
9/5  66/51/59/-8/0.08/179/23         20 NNE AERO 20 MPH NNE RMY 21
9/6  68/46/57/-10/0.00/751/97        18 WSW AERO 17 MPH WSW RMY N/A
9/7  78/51/65/-1/0.00/594/77         20 WSW AERO 21 MPH WSW RMY 21
9/8  74/50/62/-4/0.00/646/84         31 NW  AERO 33 MPH NW  RMY 32
9/9  69/47/58/-8/T/529/69            23 SW  AERO 23 MPH SSW RMY N/A
9/10 73/56/65/0/0.03/007/01          30 S   AERO 32 MPH S   RMY 33
9/11 93/68/81/+16/0.00/654/86        25 SW  AERO 27 MPH SW  RMY N/A
9/12 85/66/76/+11/0.47/455/60        32 S   AERO 33 MPH S   RMY 34   TSTM
9/13 79/58/69/+5/0.17/242/32         24 NNW AERO 25 MPH NNW RMY 23
9/14 67/52/60/-4/0.00/361/48         21 NW  AERO 21 MPH NW  RMY 21
9/15 70/48/59/-5/0.00/547/73         17 WSW AERO 18 MPH WSW RMY 20
9/16 66/46/56/-7/0.02/179/24         29 NNW AERO 31 MPH NNW RMY 30
9/17 60/40/50/-13/0.00/722/97        27 NNE AERO 27 MPH NNE RMY 26
9/18 73/47/60/-2/0.00/726/98         18 W   AERO 18 MPH WSW RMY 20
9/19 78/51/65/+3/0.00/731/99         17 WSW AERO 16 MPH WSW RMY 18
9/20 78/54/66/+4/0.00/706/96         18 SSW AERO 18 MPH SSW RMY 23
9/21 74/57/66/+4/T/512/70            35 S   AERO 40 MPH S   RMY N/A
9/22 70/49/60/-1/0.39/365/50         38 S   AERO 39 MPH S   RMY 42
9/23 63/43/53/-7/0.00/711/98         25 NW  AERO 26 MPH NW  RMY 28
9/24 65/40/53/-7/0.00/702/97         22 ENE AERO 22 MPH ENE RMY 23
 
9/25 our morning low temp: 45F; the normal low is now 51F
    
DAILY RECORDS FOR SEPTEMBER 2013
9/1  - NEW DAILY RECORD MAXIMUM PRECIPITATION OF 2.32 INCHES;
       surpasses previous record of 1.60 inches set in 1927
9/11 - TIED DAILY RECORD MAXIMUM HIGH TEMPERATURE OF 93F;
       ties record of 93F set in 1983
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR SEPTEMBER 25
HIGH 87F IN 1970
LOW 31F IN 1950
PRECIP 2.68 INCHES IN 1961
PEAK GUST 63 MPH SSW IN 1991
 
RECORDS FOR SEPTEMBER 26
HIGH 91F IN 2007
LOW 36F IN 1905,1922,1978
PRECIP 3.84 INCHES IN 1888
PEAK GUST 54e MPH S IN 1977
 
TODAY'S REPORT PREPARED BY: Robert Skilling