BLUE HILL METEOROLOGICAL OBSERVATORY 
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, AUGUST 29, 2011  
ALL TIMES ARE IN EASTERN STANDARD TIME
 
TROPICAL STORM IRENE.....
ALL TIMES IN EASTERN DAYLIGHT TIME 
 
Tropical Storm Irene brought peak wind gusts over 80 MPH
to the Observatory and 1.98 inches of rainfall.
Below is the list of peak gusts as recorded by the
various wind systems:
 
Recorded on Sunday, August 28, 2011
 
Aerovane:  89 MPH SE @ 11:03 AM 
Merlin:    84 MPH SSE
RM Young:  82 MPH
ASOS:      81 MPH SSE @ 11:35 AM
Maestro:   79 MPH
420C:      77 MPH SE @ 11:03 AM (our manual record system) 
Davis:     73 MPH SSE @ 11:37 AM
 
Peak sustained winds (2-min. avgs)
Davis:     50 MPH SE @ 1:45 PM
ASOS:      47 MPH  
Contacting fastest mile: 47 MPH (corrected) SSE
 
GREATEST ONE HOUR AVERAGE: 44 MPH (corrected) SE/SSE 11-12 NOON, 1-2 PM
 
TIME RESOLUTION OF GUSTS ON VARIOUS RECORDERS...
One cause of the differences among the various wind gust 
recording equipment at the Observatory is the amount of time
over which the wind speed is averaged to obtain the gust. 
Below are the response times of the gust recorders
as best we know them.
Aerovane: 1 SEC. ?
Merlin: ?
Young: 1 sec
ASOS: 3 sec 
Maestro: ?
420C: 1-2 sec
Davis: 2.25 sec
 
August will finish in the top ten wettest Augusts on record at
the Observatory.  
 
WETTEST AUGUSTS (inches)
1) 18.78  1955
2) 11.44  1946
3) 10.72  1927
4)  8.92  1976
5)  8.68  2010
6)  8.58  1917
7)  8.00  1924
8)  8.36  2011 (through 28th)
9)  7.72  1975
10  7.48  1936
 
Today's observations:                                                                                
7 A.M.  
Weather: Clear, few stratocumulus distant NW-NNW,
altocumulus/altocumulus lenticularis, cirrus distant
ENE-SSE 
Temperature: 59F, Dew point: 53F; Wind: WSW at 11 kts
Sea-level pressure: 29.83 inches Hg, rising
Visibility: 75 miles
24-hour precip: 1.02 inches
6-hour min. temp: 56F
BHO SA 1155 CLR 75 103/59/53/2511/983/
FEW SC DSNT NW ALG HRZN AC/ACSL/CI DSNT ENE-SSE/
8/541 51030 MANUAL 70102 ASOS 70103 10061 20056
 
10 A.M.
Weather: Clear, few stratocumulus distant WNW-N,
cirrus distant E-SE  
Temperature: 70F, Dew Point: 53F; Wind: ESE at 30G49KT,
Sea-level pressure: 29.89 inches Hg, rising
Visibility: 80 miles 
BHO SA 1455 CLR 80 123/70/53/2106/989/ FEW SC DSNT WNW-N
FEW CI DSNT E-SE/ 53020 
 
1 P.M.
Weather: Clear, small cumulus WSW-NNE, cirrus distant NW  
Temperature: 75F, Dew Point: 53F; Wind: SW at 7 kts
Wind: Direction variable S-W
Sea-level pressure: 29.90 inches Hg, rising
Visibility: 85 miles 
6-hour max. 76F
BHO SA 1755 CLR 85 126/75/53/2207/990/ SML CU WSW-NNE CI DSNT NW/
WND 19V27/ 8/101 53004 10076 20059
 
WEATHER SUMMARY FOR SUNDAY, AUGUST 28
 
TEMPERATURE (DEGREES F)
MAX.....72    NORMAL.....76
MIN.....62    NORMAL.....59
MEAN....67    NORMAL.....68
 
DEPARTURE FROM 30-YEAR NORMAL.....................-1
TOTAL DEPARTURE FOR THE MONTH....................+35 [+1.1 DEGREES/DAY]
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY..............77 SE  AT 10:03 A.M. 
                   AEROVANE...............89 SE AT 10:03 A.M. #
                   ASOS...................81 SSE AT 10:35 A.M.
                   DAVIS..................73 SSE AT 10:37 A.M. RMY: 82 MPH
THE FASTEST MILE FOR YESTERDAY............57 SSE AT 12:43 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE.............47 SE  AT 11:07 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE............50 SE  AT 12:45 P.M.
AVERAGE WIND SPEED AND DIRECTION........31.3 E
                   ASOS.................27.3  
                   DAVIS................26.7 SE [140 deg]

# may have registered too high a gust….
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....1.02  DEPARTURE.........+0.88
                         ASOS..............1.03  
TOTAL PRECIPITATION FOR THE MONTH..........8.36  DEPARTURE.........+4.72
                         ASOS..............8.38
TOTAL PRECIPITATION FOR THE YEAR..........38.05  DEPARTURE.........+5.00
                        ASOS..............38.56**
**ASOS data is in error due to system failure on 1/12-13
 
PRELIMINARY CLIMATE SUMMARY FOR AUGUST 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
 
8/1  91/69/80/+8/T/503/58       24 S
8/2  88/63/76/+4/0.15/657/76    27 NNE AERO 34 MPH TSTM
8/3  76/59/68/-4/0.00/673/78    18 ENE AERO 25 MPH
8/4  77/62/70/-2/0.00/783/91    20 NE  
8/5  78/61/70/-2/0.00/575/67    20 SE
8/6  85/66/76/+4/0.01/265/31    22 SSW AERO 28 MPH
8/7  73/67/70/-1/1.09/000/00    33 SSE AERO 39 MPH
8/8  80/70/75/+4/0.26/332/39    15 NNW
8/9  77/64/71/0/0.82/433/51     29 ESE AERO 36 MPH RMY 32 MPH TSTM **
8/10 79/61/70/-1/1.15/364/43    18 W   AERO 21 MPH RMY 18 MPH
8/11 79/61/70/-1/0.00/776/92    24 W   AERO 29 MPH RMY 27 MPH
8/12 81/58/70/-1/0.00/817/97    18 WNW AERO 25 MPH RMY 21 MPH
8/13 82/63/73/+2/0.00/512/61    15 SSW AERO 21 MPH RMY 19 MPH
8/14 74/65/70/0/0.04/000/00     21 S   AERO 28 MPH RMY 23 MPH
8/15 67/58/63/-7/1.89/000/00    40 NNE AERO 43 NNE RMY 41 MPH
8/16 69/58/61/-6/T/0.09/058/07  21 WNW AERO 24 MPH RMY 19 MPH
8/17 83/61/72/+2/0.00/813/98    20 W   AERO 24 MPH RMY 21 MPH
8/18 85/64/75/+5/0.00/.../..    24 SSW AERO 30 MPH RMY 26 MPH
8/19 85/67/76/+6/T/371/45       31 W   AERO 37 MPH RMY 31 MPH TSTM 
8/20 83/67/75/+6/0.01/411/50    20 SSE AERO 25 MPH RMY 22 MPH
8/21 82/66/74/+5/0.04/311/38    35 S   AERO 42 MPH RMY 36 MPH
8/22 75/60/68/-1/0.67/661/81    33 W   AERO 40 MPH RMY 37 MPH
8/23 77/55/66/-3/0.00/724/89    20 WSW AERO 24 MPH RMY 21 MPH  
8/24 78/61/70/+1/0.00/.../..    33 S   AERO 40 MPH RMY 36 MPH
8/25 83/65/74/+6/..../.../..    36 SSW AERO 44 MPH RMY 39 MPH
8/26 84/66/75/+7/..../.../..    26 WSW AERO 32 MPH RMY N/A
8/27 79/67/73/+5/..../.../..    23 E   AERO 28 MPH RMY N/A
8/28 72/62/67/-1/..../000/00    77 SE  AERO 89 MPH RMY 82 MPH "IRENE"
 
8/29 our morning low temp: 56F; the normal low is now 50F 
 
** please see added line in, "Preliminary Climate Summary"
above regarding the start of wind gust record from the
R.M. Young digital recorder on 8/9
 
DAILY RECORDS FOR AUGUST 2011
None so far.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR AUGUST 29
HIGH 95F IN 1953
LOW 41F IN 1982
PRECIP 2.88 INCHES IN 1962
PEAK GUST 70e MPH S IN 1949
 
RECORDS FOR AUGUST 30
HIGH 94F IN 1953
LOW 39F IN 1965
PRECIP 2.75 INCHES IN 1936
PEAK GUST 43 MPH NW IN 1965
 
TODAY'S REPORT PREPARED BY: Robert Skilling/Patrick Peters