BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, JULY 15, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
SUNNY, HAZY WARM AND VERY HUMID CONDITIONS OF TODAY
HAVE REPLACED YESTERDAY'S SUNNY, WARM AND DRY WEATHER 
WITH EXCELLENT VISIBILITY UP TO 75 MILES
 
Yesterday's high temperature of 82 degrees came in the 
very late afternoon at 5:10 P.M. EDT after the seabreeze,
which dropped temperatures from 80 degrees to 75 degrees
at mid-afternoon, suddenly quit. The airmass was unsually
dry for mid-July yesterday with dewpoints in the 50's but 
all that has changed today. Increasing humidity overnight 
has sent our dewpoints rising well into the 60's by late
this morning.   
 
The excellent visibility, up to 75 miles yesterday, has been 
replaced by hazy conditions with only a 10 to 15-mile view 
this morning in a warm and increasingly humid airmass.    
 
Yesterday became the the 4th day this morning to average 
exactly normal during a month that began quite cool during
the first three days. Since then temperatures have continued
to average only very slightly warmer than normal and by only 
about a degree.  The result, the month is still averaing 
almost a degree cooler than normal through the first 2 weeks. 
 
Today's observations:
 
7 A.M.   
Weather: Clear but with few altocumulus castellanus 
overhead-NE and S-SW and NNW     
Temperature: 71F, Dew point: 65F, Wind: SSE at 12 kts 
Wind: Variability SE-SSW 
Sea-level pressure: 29.87 inches Hg, steady
Visibility: 10 miles and hazy
6-hour min temp: 65F     
24-hour rainfall:0.00   
BHO SA 1155 CLR 10 116/71/65/1612/987/ FEW ACC OVHD-NE
AND S-SW AND NNW HAZY WND 14V20 GST 22 KTS PST HR/ 
8/080 50000 10071 20065 
 
10 A.M.   
Weather: Clear, hazy, few cumulus fractus forming  
Temperature: 81F, Dew point: 68F, Wind: S at 13G21 kts 
Wind: Variability SE to SSW  
Sea-level pressure: 29.86 inches Hg, falling
Visibility: 15 miles, hazy  
BHO SA 1455 CLR 15 111/81/68/1713G21/986/ 
FEW CUFRA FRMG HAZY WND 13V20/ 8/100 58005 
 
WEATHER SUMMARY FOR SATURDAY, JULY 14
 
TEMPERATURE (DEGREES F)
MAX.....82    NORMAL.....81 
MIN.....62    NORMAL.....62
MEAN....72    NORMAL.....72
DEPARTURE FROM 30-YEAR NORMAL....... 0
TOTAL DEPARTURE FOR THE MONTH.......-8  (-0.8 DEGREES/DAY)
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY..............33 SSE AT 5:55 P.M.     
                   AEROVANE...............34 SSE AT 5:55 P.M. .    
                   ASOS...................N/A  #
                   DAVIS..................33 SSE AT 5:51 P.M.          
FASTEST MILE FOR YESTERDAY................24 SSE AT 5:42,5:52 P.M.       
MAXIMUM 2-MINUTE ASOS AVERAGE.............N/A  # 
MAXIMUM 2-MINUTE DAVIS AVERAGE............23 SSE  AT 5:53 P.M.           
AVERAGE WIND SPEED AND DIRECTION......... 9.7 SSE 
                   ASOS...................N/A  #
                   DAVIS..................8.9 S [190 deg]  
 
# ASOS WINDS SWITCHED OFF BY NWS 6/6, IT IS NOT KNOWN WHEN 
THAT DATA WILL RESUME
 
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 JULY...............0.99  DEPARTURE.....-0.71 
                         ASOS..............0.91    
TOTAL PRECIPITATION FOR THE YEAR..........27.97  DEPARTURE.....+0.60 
                   ASOS FOR YEAR..........27.32    
 
PRELIMINARY CLIMATE SUMMARY FOR JULY 2007......CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
 
AERO: Aerovane recording wind system when significant
TSTM: Thunderstorm day
....: Data not yet available
 
7/1  70/52/61/-9/0.02/649/71/28 W      
7/2  73/50/62/-8/0/841/92/   29 WNW 
7/3  75/53/64/-6/0/839/92/   23 NW 
7/4  78/58/68/-2/0.09/465/51/45 SSE 
7/5  80/61/71/ 0/0.25/383/42/38 SSE TSTM   
7/6  83/62/73/+2/0.01/482/53/46 WNW TSTM  
7/7  81/60/71/0/0/.../../    32 WSW   
7/8  90/62/76/+5/0.41/.../../36 NW Aero 33 MPH TSTM 
7/9  86/61/74/+3/0.20/354/39 27 NNE TSTM
7/10 80/62/71/0/0/680/75     27 S 
7/11 84/70/77/+5/T/393/43    32 S
7/12 81/64/73/+1/.01/810/90  27 WNW
7/13 84/62/73/+1/0/.../..    36 WSW
7/14 82/62/72/0/T/.../..     33 SSE
 
7/15 morning low temp. 65 deg; normal low now 62 deg.   

NEW DAILY RECORDS FOR JULY 2007: 
 
None to date
 
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