BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, MAY 17, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
Congratulations to observer Stephanie Radner; 
she gave birth to a baby girl yesterday afternoon.
 
THUNDERSTORM PASSING TO OUR NORTH BROUGHT 40 MPH GUST 
AT MID-AFTERNOON ON WEDNESDAY.....
A HALF INCH OF RAINFALL RECORDED IN EVENING SHOWERS AND 
THAT INCLUDED AN EARLY EVENING THUNDERSTORM 
LOW OVERCAST WITH NORTHEAST WINDS KEEPING IT 
VERY COOL--IN THE 40'S TODAY
 
Last evening's showers brought some beneficial rainfall
during a very dry month to date.  A peak wind gust to 
40 MPH NW was record in an outflow burst of wind from 
a thunderstorm passing to our N around 3:30 p.m. 
Low overcast clouds and a very cool northeast wind is 
prevailing today.

Today's observations:
 
7 A.M.   
Weather: Obscurement with heavy fog    
Temperature: 43F, Dew point: 43 Wind: NE at 10G14 kts 
Sea-level pressure: 30.02 inches Hg, rising   
Visibility: 1/16 in heavy fog     
24-hourly precip: 0.55 inch
6- hourly min temp. 43 deg.  
BHO SA 1155 W3 X 1/16F 166/43/43/0510G14/002/ 8//// 51033 MANUAL 
6001/ MANUAL 70055 ASOS 70051 10044 20043 
 
10 A.M.
Weather: Low overcast stratus   
Temperature: 44F, Dew point: 43 Wind: NE at 09 kts 
Sea-level pressure: 30.10 inches Hg, rising   
Visibility: 12 miles in thin fog, 20 miles NE     
BHO SA 1455 E5 OVC 12 193/44/43/0509/010/ THN F VSBY NE 20/ 8/6// 
51027 
   
1 P.M.
Weather: Overcast stratocumulus, with bright spots in overcast 
Temperature: 49F, Dew point: 43F, Wind: NE at 08 kts 
Sea-level pressure: 30.16 inches Hg, rising   
Visibility: 35 miles, 25 SW-NW and 45 NE, light haze     
Six hourly max. temp: 49 deg.
BHO SA 1755 E12 OVC 35 214/49/43/0508/016/ BRGHT SPTS IOVC VSBY 
SW-NW 25 NE 45 LGT HZ WND 02V08/ 8/5// 51021 10049 20043  
 

WEATHER SUMMARY FOR WEDNESDAY, MAY 16 
 
TEMPERATURE (DEGREES F)
MAX.....66    NORMAL.....67 
MIN.....44    NORMAL.....47
MEAN....55    NORMAL.....57
DEPARTURE FROM 30-YEAR NORMAL...........-2
TOTAL DEPARTURE FOR THE MONTH..........+63 (+3.7 DEGREES/DAY)
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY...........10  DEPARTURE........+ 1
TOTAL HEATING UNITS FOR THE MONTH..........117  DEPARTURE........-55  
TOTAL HEATING UNITS FOR THE SEASON........5733  DEPARTURE.......-467
TOTAL HEATING UNITS LAST SEASON TO DATE...5637  DIFFERENCE.......+96 
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............40 NW   AT   2:38 P.M.   
                   AEROVANE.............37 NW   AT   2:38 P.M.    
                   ASOS.................36 NW   AT   2:39 P.M.   
                   DAVIS................38 NW   AT   2:38 P.M.  
FASTEST MILE FOR YESTERDAY..............29 NNW  AT   2:41 P.M.    
MAXIMUM 2-MINUTE ASOS AVERAGE...........29 NNW  AT   2:41 P.M.     
MAXIMUM 2-MINUTE DAVIS AVERAGE..........29 NNW  AT   2:41 P.M.   
AVERAGE WIND SPEED AND DIRECTION.......10.8 NE   
ASOS FOR THE DAY.......................10.8                    
DAVIS FOR THE DAY .....................10.3 NE [040 degrees] 
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.55   DEPARTURE....+0.43
                         ASOS..............0.51  
TOTAL PRECIPITATION FOR THE MONTH..........0.66   DEPARTURE....-1.31 
                         ASOS..............0.60    
TOTAL PRECIPITATION FOR THE YEAR..........21.08   DEPARTURE....+1.16
                         ASOS.............20.57    
 
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 85/60/73/+18/0/0/692/80     29 S     Aero 27 MPH S
5/11 74/60/67/+12/0.02/0/355/41  23 S
5/12 63/47/55/-1/0.02/0/.../..   32 NE    
5/13 65/46/56/0/T/0/775/89       33 WNW   Aero 33 MPH WNW 
5/14 73/43/58/+1/0/0/822/94      30 SSW
5/15 80/50/65/+8/0.01/0/.../..   30 S     TSTM evening   
5/16 66/44/55/-2/0.54/0/.../..   40 NW    TSTM P.M. 
 
5/17 morning low temp. 43 deg; normal now 47 deg. 
     rainfall: 0.01 in light drizzle 
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR MAY 17
HIGH 88F IN 1974, 1977
LOW 34F IN 1956, 1957
PRE 2.07 INS IN 1916
PEAK GUST 52 MPH SW IN 1967, W IN 1974
 
RECORDS FOR MAY 18
HIGH 88F IN 1906, 1936, 1986
LOW 35F IN 2002
PRE 1.58 INS IN 2002
SNOW TRACE IN 2002 (Ice pellets)
PEAK GUST 64 MPH SSW IN 2000
 
TODAY'S REPORT PREPARED By: Robert Skilling