BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, MAY 10, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
Today's observations:
 
7 A.M.   
Weather: Overcast thin cirrus clouds
Temperature: 65F, Dew point: 62F, Wind: SSW 7 kts 
Sea-level pressure: 30.01 inches Hg, rising
Visibility: 10 miles, thin fog  
6-hour min. 60 deg. 
BHO SA 1155 250 –OVC 10 165/65/62/2007/001/ FEW STFRA SE-SW THN F/ 
8/601 53006 10065 20060
 
10 A.M.
Weather: Overcast thin cirrus clouds 
Temperature: 77F, Dew point: 62F, Wind: S at 9 kts
Wind: Direction variable SSE-SSW   
Sea-level pressure: 30.00 Hg, falling   
Visibility: 15 miles, hazy   
BHO SA 1455 250 –OVC 15 158/77/62/1909/000/ HZY WND 16V24/ 
8/001 58007
 
1 P.M. 
Weather: Scattered cumulus, thin overcast cirrus clouds  
Temperature: 83F, Dew point: 60F, Wind: S at 10 kts
Wind: Direction variability ESE-SW  
Sea-level pressure: 29.96 Hg, falling   
Visibility: 18 miles, hazy  
BHO SA 1755 40 SCT 250 SCT 300 –OVC 18 146/83/60/1810/996/ 
FEW MDT CU HZY WND 12V23/ 8/207 58012 10085 20065
 
WEATHER SUMMARY FOR WEDNESDAY, MAY 9
 
TEMPERATURE (DEGREES F)
MAX.....85    NORMAL.....65 
MIN.....54    NORMAL.....45
MEAN....70    NORMAL.....55
DEPARTURE FROM 30-YEAR NORMAL..........+15
TOTAL DEPARTURE FOR THE MONTH..........+27 (+2.8 DEGREES/DAY)
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY........... 0  DEPARTURE........-11
TOTAL HEATING UNITS FOR THE MONTH...........83  DEPARTURE........-25 
TOTAL HEATING UNITS FOR THE SEASON........5699  DEPARTURE.......-435
TOTAL HEATING UNITS LAST SEASON TO DATE...5521  DIFFERENCE......+178
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............30  S   AT  7:27 P.M.   
                   AEROVANE.............29  S   AT  7:28 P.M. *
                   ASOS.................29  S   AT  7:28 P.M.     
                   DAVIS................32  SSW AT 12:03 A.M.      
FASTEST MILE FOR YESTERDAY..............22  S   AT  7:29 P.M. *   
MAXIMUM 2-MINUTE ASOS AVERAGE...........24  S   AT  7:29 P.M.    
MAXIMUM 2-MINUTE DAVIS AVERAGE..........25  SSW AT 12:06 A.M.     
AVERAGE WIND SPEED AND DIRECTION.......14.7 SSW  
                    ASOS...............14.5       
                    DAVIS..............15.1 SSW [198 degrees]
* last of several occurrences...
 
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..........0.06   DEPARTURE....-1.07 
                         ASOS..............0.04    
TOTAL PRECIPITATION FOR THE YEAR..........20.48   DEPARTURE....+1.40
                         ASOS.............20.01    
 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE.......0.0
TOTAL SNOWFALL FOR THE MONTH................0.0  DEPARTURE......-0.1 
TOTAL SNOWFALL FOR THE SEASON..............27.6  DEPARTURE.....-32.5  
    
PRELIMINARY CLIMATE SUMMARY FOR MAY 2007......CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
 
AERO: Aerovane recording wind system when significant
TSTM: Thunderstorm day
....: Data not yet available
 
5/1  67/44/56/+4/0/0/624/74      33 NW 
5/2  64/45/55/+3/0.06/0/381/45   36 NW    Aero 33 MPH WNW
5/3  67/42/55/+2/0/0/849/100     38 W     Aero 37 MPH W
5/4  66/44/55/+2/0/0/842/99      39 WNW   Aero 40 MPH WNW 
5/5  65/45/55/+2/0/0/384/45      33 N  
5/6  51/42/47/-7/T/0/514/60      36 N     Aero 33 MPH N 
5/7  68/39/54/0/0/0/798/93       25 S
5/8  77/43/60/+6/0/0/851/99      33 S     Aero 31 MPH S 
5/9  85/54/70/+15/0/0/707/92     30 S
 
5/10  morning low temp. 60 deg.; normal now 45 deg.    
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR MAY 10
HIGH 93F IN 1896
LOW 29F IN 1900
PRE 1.85 INS IN 1998
SNOW 2.8 INS 1977 (7.8 INS TOTAL 5/9-5/10 1977)
PEAK GUST 64 MPH S IN 1990
 
RECORDS FOR MAY 11
HIGH 90F IN 1993
LOW 28F IN 1900
PRE 1.28 INS IN 1957
SNOW 1.0 INS IN 1907 (LATEST MEASURABLE SNOW ON RECORD)
PEAK GUST 75e MPH NW IN 1945
 
TODAY'S REPORT PREPARED By: Stephanie Radner