BLUE HILL METEOROLOGICAL OBSERVATORY 
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, OCTOBER 6, 2011
ALL TIMES ARE IN EASTERN STANDARD TIME
 
FIRST TRULY FALL FEELING DAY OF THIS SEASON
LOW TEMP. OF 40F; COLDEST SINCE 36F ON 23 APRIL
UNLIMITED VISIBILITY TODAY IN THE VERY COOL
AND DRY AIR MASS. 
 
After two weeks of consecutive days during which the daily
mean temperature averaged above normal, yesterday broke the
long stretch of days with a average which was 2 degrees below
the normal. The arrival of the new chilly air mass yesterday
brought peak wind gusts of over 40 MPH and dew points which
fell from the upper 40's to the middle 30's by late in the
day.  A few brief light rain showers accompanied the colder
air as it arrived. Our thermometer skidded from 60 degrees
at 5 p.m. to 42 degrees by midnight last night. 
The distant New Hampshire mountains were clearly visible
today and visibility rose to an estimated 90 miles during
this morning.
 
Today's observations:
 
7 A.M.  
Weather: Scattered cirrus, layer SSW-NNW advancing
Temperature: 42F, Dew point: 32F; Wind: WNW at 11 kts,
Wind: Direction variable WSW to NW,
Wind: Gust to 19 kts past hour
Sea-level pressure: 30.28 inches Hg, rising
Visibility: 80 miles  
24-hour precip: trace
6-hour min: 40F
BHO SA 1155 250 SCT 80 255/42/32/2911/028/
CI LYR DSNT SSW-NNW INVADING GST 19 KTS PST HR/
WND 25V32/ 8/005 53010 10042 20040
 
10 A.M.
Weather: Thin broken cirrus, few lower cirrus 
Temperature: 51F, Dew Point: 29F; Wind: NW at 15G24 kts,
Wind: Peak wind 26 kts NNW @ 36 mins. past the hour
Wind: Direction variable W-NNW 
Sea-level pressure: 30.28 inches Hg, steady
Visibility: 90 miles   
BHO SA 1455 300 –BKN 90 255/51/29/3115G24/028/ FEW LWR CI 
PK WND 3326/36/ WND 26V34/ 8/001 58000
 
1 P.M. 
Weather: Thin broken cirrus, cirrocumulus 
Temperature: 58F, Dew Point: 29F; Wind: WNW at 9 kts,
Wind: Gust to 25 kts past hour
Wind: Direction variable WSW-NNW
Sea-level pressure: 30.25 inches Hg, falling
Visibility: 90 miles  
6-hour max. temp: 59F
BHO SA 1755 250 –SCT 300 –BKN 90 242/58/29/3009/025/ PTCHS CC
GST 25 KTS PST HR WND 25V33/ 8/009 58013 10059 20042
 
WEATHER SUMMARY FOR WEDNESDAY, OCTOBER 5
 
TEMPERATURE (DEGREES F)
MAX.....63    NORMAL.....64
MIN.....42    NORMAL.....46
MEAN....53    NORMAL.....55
 
DEPARTURE FROM 30-YEAR NORMAL.....................-2
TOTAL DEPARTURE FOR THE MONTH....................+14 [+2.6 DEGREES/DAY]
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY..............43 WNW AT 12:40 P.M. [ob of dial)   
                   AERO...................42 WNW AT 12:40 P.M. 
                   ASOS...................40 WNW AT 12:40 P.M. 
                   DAVIS..................40 WNW AT 12:40 P.M. RMY: 44 MPH
THE FASTEST MILE FOR YESTERDAY............30 WNW AT 12:43 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE.............28 WNW AT 12:44 P.M. 
MAXIMUM 2-MINUTE DAVIS AVERAGE............27 WNW AT 12:43 P.M. 
AVERAGE WIND SPEED AND DIRECTION.......14.0 NW
                   ASOS................13.7  
                   DAVIS...............12.3 NNW [330 deg]
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...trace DEPARTURE..........-0.14
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........2.82 DEPARTURE..........+2.12
                         ASOS..............2.76
TOTAL PRECIPITATION FOR THE YEAR..........46.88 DEPARTURE..........+8.58
                        ASOS..............47.22**
**ASOS data is in error due to system failure on 1/12-13
 
PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 2011 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane wind recording system gust when significant
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
 
10/1 70/55/63/+6/..../.../..     24 NE  AERO N/A        RMY 25 MPH TSTM
10/2 64/54/59/+3/..../.../..     24 NNE AERO 27 MPH NNE RMY 26 MPH
10/3 67/53/60/+4/..../.../..     20 S   AERO 22 MPH S   RMY 22 MPH
10/4 65/52/59/+3/..../.../..     24 NW  AERO 25 MPH NNW RMY 25 MPH
10/5 63/42/53/-2/T/.../..        43 WNW AERO 42 MPH WNW RMY 44 MPH
 
10/6 our morning low temp: 40F; the normal low is now 46F
 
DAILY RECORDS FOR OCTOBER 2011
None so far.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR OCTOBER 6
HIGH 83F IN 1990, 2007
LOW 26F IN 1965
PRECIP 3.78 INCHES IN 1962
PEAK GUST 60e MPH S IN 1942
 
RECORDS FOR OCTOBER 7
HIGH 88 IN 1963 (RECORD FOR MONTH)
LOW 30 IN 1904,1986
PRECIP 1.75 INCHES IN 1972
PEAK GUST 54 W IN 2009
 
TODAY'S REPORT PREPARED BY: Robert Skilling