BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, MAY 25, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
WARM AND SUMMER-LIKE AIRMASS ARRIVED OVERNIGHT
SUNNY BUT VERY HAZY CONDITIONS TODAY
 
Our overnight low temperature of 66 degrees was easily the 
warmest of the season to date and well above the normal of 
50 degrees.  Our temperature had reached the 80's at mid-
morning and we'll likely be near or even above the record 
high reading for this date which is 89 degrees in 1981.
 
Visibility is reduced to only 10 to 15 miles in the haze
this morning. 
 
Today's observations:
 
7 A.M.   
Weather: Clear, hazy 
Temperature: 71F, Dew point: 56F, Wind: W at 13 kts 
Sea-level pressure: 30.15 ins. Hg, steady  
Visibility: 12 miles, hazy     
6- hourly min temp. 66 deg.  
BHO SA 1155 CLR 12 210/71/56/2713/015/ HAZY/ 50002 10071 20066
   
10 A.M. AND 1 P.M. obs not available today
 
WEATHER SUMMARY FOR THURSDAY, MAY 24 
 
TEMPERATURE (DEGREES F)
MAX.....86    NORMAL.....70 
MIN.....50    NORMAL.....50
MEAN....68    NORMAL.....60
DEPARTURE FROM 30-YEAR NORMAL...........+8
TOTAL DEPARTURE FOR THE MONTH..........+25 (+0.8 DEGREES/DAY)
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY........... 0  DEPARTURE........- 6
TOTAL HEATING UNITS FOR THE MONTH..........212  DEPARTURE........-20  
TOTAL HEATING UNITS FOR THE SEASON........5828  DEPARTURE.......-430
TOTAL HEATING UNITS LAST SEASON TO DATE...5710  DIFFERENCE......+118 
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............25 WSW AT 10:50 P.M.  
                   AEROVANE.............21 WSW AT 10:50 P.M. 
                   ASOS.................28 W   AT 10:50 P.M. **   
                   DAVIS................24 WSW AT 10:50 P.M.   
FASTEST MILE FOR YESTERDAY..............19 WSW AT 11:36 P.M.   
MAXIMUM 2-MINUTE ASOS AVERAGE...........18 W   AT 11:08 P.M. **  
MAXIMUM 2-MINUTE DAVIS AVERAGE..........17 WSW AT N/A   
AVERAGE WIND SPEED AND DIRECTION........9.2  SW
                   ASOS.................10.7 **  
                   DAVIS................9.4 SSW [210]
** new ASOS wind system [ULTRASONIC] installed
 
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..........3.71  DEPARTURE.....+0.78 
                         ASOS..............3.64    
TOTAL PRECIPITATION FOR THE YEAR..........24.13  DEPARTURE.....+3.25 [corrected]
                         ASOS.............23.61    
 
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     TSTM A.M.  
5/12 63/47/55/-1/0.02/0/469/54   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/+8/0.01/0/210/24   30 S     TSTM evening   
5/16 66/44/55/-2/0.54/0/527/60   40 NW    TSTM P.M.  
5/17 50/42/46/-11/0.01/0/009/01  28 NE  
5/18 42/39/41/-17/1.93/0/000/00  37 NNE
5/19 51/40/46/-12/0.71/0/000/00  25 NNW
5/20 59/49/54/-4/0.41/0/035/04   30 W     TSTM P.M.  
5/21 63/46/55/-4/0/0/693/78      29 WNW
5/22 71/46/59/0/0/0/800/90       25 SSE  
5/23 74/47/61/0/0/757/85         30 SSE 
5/24 86/50/68/+8/0/0/.../..      25 WSW
 
5/25 morning low temp. 66 deg; normal low now 50 deg. 
 
NEW DAILY RECORDS FOR MAY:
 
5/18 Record low maximum temperature, 42, previous 48 in 1895 and 1956.
5/18 Record daily precipitation, 1.93, previous 1.58 inches in 2002.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR MAY 25
HIGH 89F IN 1981
LOW 37F IN 1967
PRECIP 3.73 INS IN 1967
PEAK GUST 83 MPH NE IN 1967 (RECORD FOR MAY)
 
RECORDS FOR MAY 26
HIGH 89F IN 1914,1965
LOW 37F IN 1972
PRECIP 1.73 INS IN 2003
SNOWFALL TRACE IN 1967 (Fell as ice pellets in nor'easter)
PEAK GUST 62 MPH NE IN 1967
 
TODAY'S REPORT PREPARED By: Robert Skilling/Nate Magee