BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, JULY 15, 2009
ALL TIMES ARE IN EASTERN STANDARD TIME
 
SUNSHINE WITH COOL, DRY WEATHER CONTINUES
APPROACHING WARMER AND HUMID WEATHER MAY
END LONG STRING OF COOLER THAN NORMAL DAYS
 
Just about full sunshine is back today after
developing cumulus and stratocumulus cloud-
iness yesterday afternoon changed the day
from sunny to cloudy by mid-afternoon.  
The July sunshine therefore remains at 57%
of possible right on the average for the
month.  Today's sunny weather should raise
this month to sunnier than average.
 
Temperatures continue cooler than normal each
day this month with no 80-degree readings and
so with each passing day we continue to set
an all-time record with no 80's in summer to
date. Another ongoing record during this cool
summer is the no 80's in July to date. The
longest stretch during this month without 80
degrees occurred in 1918 when it ended on
July 16 with 85 degrees. We may just equal that
record if 80 degrees occurs for the first time
this month and summer tomorrow.
The extended stretch of below normal daily
mean temperatures began with 28 June.
 
Today's observations:
 
7 A.M.  
Weather: Clear, few stratocumulus distant NE-E   
mperature: 62F, Dew point: 52F, Wind: WSW at 11 kts
Sea-level pressure: 30.10 inches Hg, steady 
Visibility: 70 miles 
6-hour minimum temp: 55F
24-hour precipitation: 0.00 inch
BHO SA 1155 CLR 70 193/62/52/2511/010/
FEW SC DSNT NE-E/ 8/500 51004 10062 20055 
 
10 A.M.  
Weather: Clear, cumulus fractus and small cumulus
forming
Temperature: 72F, Dew point: 52F, Wind: W at 10 kts,
Wind: direction variable SSW to WNW  
Sea-level pressure: 30.07 inches Hg, falling
Visibility: 75 miles
BHO SA 1455 CLR 75 184/72/52/2610/007/
CUFRA/SML CU FRMG ALQDS WND 21V30/ 8/100 58009
 
1 P.M.  
Weather: Clear, cumulus fractus, cumulus in all
quadrants 
broken cirrus 
Temperature: 77F, Dew point: 50F, Wind: SW at 11 kts.
Wind: gust to 22 kts past hour,
Wind: direction variable south to west
Sea-level pressure: 30.04 inches hg, falling
Visibility: 75 miles 
6-hourly max. temp. 77F
BHO SA 1755 CLR 75 174/77/50/2311/004/ CUFRA/SML CU ALQDS WND
GST 22 KTS PST HR WND 17V28/ 58010 10077 20062
 
WEATHER SUMMARY FOR TUESDAY, JULY 14
 
TEMPERATURE (DEGREES F)
MAX.....75    NORMAL.....81
MIN.....56    NORMAL.....62
MEAN....66    NORMAL.....72
 
DEPARTURE FROM 30-YEAR NORMAL...........-6
TOTAL DEPARTURE FOR THE MONTH..........-84  [-6.2 DEGREES/DAY]
 
HEATING DEGREE DATA WILL RESUME IN SEPTEMBER
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY.............25 WNW AT  7:57 P.M.
                   AEROVANE..............23 WNW AT  7:57 P.M.  
                   ASOS..................23 WNW AT  7:58 P.M.  
                   DAVIS.................25 WNW AT  7:57 P.M. 
FASTEST MILE FOR YESTERDAY...............18 WSW AT  3:13 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE............18 WSW AT  3:13 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE...........19 W   AT  7:58 P.M. 
AVERAGE WIND SPEED AND DIRECTION.......10.2 W 
                   ASOS.................9.5
                   DAVIS...............10.0 W [260 DEG]
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE....-0.12
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........3.09  DEPARTURE....+1.39
                         ASOS..............3.15 
TOTAL PRECIPITATION FOR THE YEAR..........26.73  DEPARTURE....-0.64
                         ASOS.............27.80
 
PRELIMINARY CLIMATE SUMMARY FOR JULY 2009 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
TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized
 
7/1  62/57/60/-10/0.51/000/00   25 NNE   TSTM
7/2  66/56/61/-9/1.00/000/00    29 SSW   TSTM
7/3  75/58/67/-3/T/283/31       23 WSW
7/4  77/59/68/-2/0/838/92       43 W     Aero 39 MPH W     
7/5  78/54/66/-5/0/856/94       33 W     
7/6  79/60/70/-1/0/883/97       20 SSE
7/7  66/58/62/-9/0.73/027/03    28 SE    TSTM
7/8  67/56/62/-9/0.23/091/10    27 NNE   TSTM
7/9  66/55/61/-10/0/689/76      23 NE
7/10 76/54/65/-6/0/896/99       21 SW
7/11 77/56/67/-5/0.29/686/76    36 S     Aero 32 MPH S
7/12 78/60/69/-3/0.33/650/72    30 SSW   TSTM
7/13 76/55/66/-6/0/802/89       32 SW 
7/14 75/56/66/-6/0/567/63       25 WNW
 
7/15 our morning low temp: 55F; the normal low is now 62F
 
NEW DAILY RECORDS FOR JULY 2009 TO DATE...
NONE
 
DAILY EXTREMES
 
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR JULY 15
HIGH 94F IN 1995
LOW 50F IN 1929, 1930
PRECIP 1.64 INS IN 1896
WIND 71 MPH WNW IN 2002
 
RECORDS FOR JULY 16
HIGH 94F IN 1968, 1980, 1983, 1999
LOW 50F IN 1889, 1903
PRECIP 0.89 INS IN 1919
WIND 48e MPH SW 1944
 
TODAY'S REPORT PREPARED BY: Robert Skilling