BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, APRIL 27, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
Today's observations:
 
7 A.M.   
Weather: Obscurement, heavy rain and fog  
Temperature: 44F, Dew point: 44F, Wind: E @ 11 kts  
Sea-level pressure: 30.04 ins. Hg, falling 
Visibility: 1/16 mile, rain and fog 
6-hour min. 43 deg.   
24-hour rainfall: 0.69 in.  
BHO SA 1155 W3 X 1/16R+F 173/44/44/1011/004/ 8//// 56011 
ASOS 60065 MANUAL 6069/ ASOS 70065 MANUAL 70069 10045 20043
 
10 A.M.
Weather: Partial obscurement, light drizzle and fog 
Temperature: 46F, Dew point: 46F, Wind: ENE @ 08 kts 
Sea-level pressure: 29.97 inches Hg, falling 
Visibility: 1/4 mile, fog   
3-hour rainfall: 0.26 in.
BHO SA 1455 –X E4 OVC 1/4L-F 150/46/46/0708/997/ LF5 
STRA DRFTG OVR SMT/ 8/7// 56023 ASOS 60031 MANUAL 6026/
 
1 P.M.
Weather: Obscurement, fog
Temperature: 47F, Dew point: 47F, Wind: WNW @ 06 kts
Sea-level pressure: 29.91 inches Hg, falling 
Visibility: 1/16 mile, fog  
6-hourly max. temp. 47 deg.
6-hour rainfall: 0.36 in.
BHO SA 1755 W2 X 1/16F 130/47/47/3006/991/ 8//// 56020 
ASOS 60041 MANUAL 6036/ 10047 20044
 
WEATHER SUMMARY FOR THURSDAY, APRIL 26
 
TEMPERATURE (DEGREES F)
MAX.....62    NORMAL.....60 
MIN.....39    NORMAL.....40
MEAN....51    NORMAL.....50
DEPARTURE FROM 30-YEAR NORMAL...........+1
TOTAL DEPARTURE FOR THE MONTH.........- 58 (-2.4 DEGREES/DAY) 
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY..........14   DEPARTURE.........-1
TOTAL HEATING UNITS FOR THE MONTH.........564   DEPARTURE.......+ 59 
TOTAL HEATING UNITS FOR THE SEASON.......5558   DEPARTURE.......-411
TOTAL HEATING UNITS LAST SEASON TO DATE..5353   DIFFERENCE......+205
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............30  SSE AT 6:59 P.M.    
                   AEROVANE.............28  SSE AT 6:69 P.M.     
                   ASOS.................28  S   AT 7:01 P.M.
                   DAVIS................30  SSE AT 6:59 P.M.     
FASTEST MILE FOR YESTERDAY..............23  SSE AT 7:01 P.M.   
MAXIMUM 2-MINUTE ASOS AVERAGE...........24  S   AT 7:01 P.M.         
MAXIMUM 2-MINUTE DAVIS AVERAGE..........21  SSE AT 7:01 P.M.      
AVERAGE WIND SPEED AND DIRECTION........9.2 SSE  
                    ASOS................9.4    
                    DAVIS...............8.5 SSE [159 degrees] 
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.69  DEPARTURE.....+0.55
                         ASOS..............0.65
TOTAL PRECIPITATION FOR THE MONTH..........8.10  DEPARTURE.....+4.30  
                         ASOS..............7.72    
TOTAL PRECIPITATION FOR THE YEAR..........19.84  DEPARTURE.....+2.41
                         ASOS.............19.36   
 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE......-0.1
TOTAL SNOWFALL FOR THE MONTH................0.2  DEPARTURE......-2.5 
TOTAL SNOWFALL FOR THE SEASON..............27.6  DEPARTURE.....-32.0  
    
PRELIMINARY CLIMATE SUMMARY FOR APRIL 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
 
4/1  59/33/46/+5/0.42/0/511/67       30 S
4/2  39/35/37/-5/0.33/0/000/00       27 E
4/3  41/32/37/-5/0.04/0/000/00       28 ENE
4/4  36/32/34/-8/0.90/0.2/000/00     38 E
4/5  43/26/35/-8/0.21/T/163/21       36 WSW
4/6  39/23/31/-12/0/0/590/76         36 WSW
4/7  40/26/33/-10/0/0/405/52         35 W
4/8  40/25/33/-11/0/0/619/79         44 W      Aero 42 MPH W
4/9  50/30/40/-4/0/0/746/95          36 W
4/10 43/30/37/-7/0/0/158/20          28 W 
4/11 51/28/40/-5/0/0/712/90          22 SSE
4/12 39/32/36/-9/0.89/T/000/00       42 E      Aero 40 MPH E
4/13 47/31/39/-6/0/0/096/12          41 W      Aero 42 MPH W
4/14 52/35/44/-2/0/0/392/49          37 W
4/15 44/35/40/-6/1.75/T/000/00       66 E      Aero 64 MPH E  
4/16 50/40/45/-1/1.56/0/000/00       73 E      Aero 73 MPH E 
4/17 40/35/38/-9/0.69/T/000/00       54 NNE    Aero 53 MPH NNE
4/18 39/36/38/-9/0.37/0/000/00       43 N
4/19 49/36/43/-4/0.02/T/285/35       38 NE     Aero 35 MPH NE 
4/20 57/36/47/-1/0/0/815/100         31 N
4/21 74/45/60/+12/0/0/753/92         24 NW
4/22 75/50/63/+14/0/0/779/95         31 SSE     
4/23 85/49/67/+18/0/0/675/82         42 S      Davis 45 MPH S 
4/24 73/50/62/+13/0/0/586/71         39 W      Aero  41 MPH W
4/25 58/43/51/+1/0.23/0/083/10       27 WNW 
4/26 62/39/51/+1/0/0/.../..          30 SSE    Aero  28 SSE
 
4/27 morning low temp. 43 deg; normal now 41 deg.  
 

NEW DAILY RECORDS FOR APRIL SO FAR....
 
4/15 - NEW RECORD HIGH PEAK WIND GUST FOR THIS DATE OF 66 MPH E; the previous   
record was 59 mph estimated from the S in 1946 and measured from the S in 1980.   
NEW RECORD DAILY RAINFALL OF 1.75 INS.; previous record 1.29 ins. in 1990.
 
4/16 - NEW RECORD HIGH PEAK WIND GUST OF 73 MPH E; the previous record for this  
date was 63 mph SSE in 1996.       
 
4/23 - EQUALED RECORD HIGH MAXIMUM TEMPERATURE OF 85 DEGREES 
set in 1908.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR APRIL 27
HIGH 93 IN 1990
LOW 28 IN 1919
PRECIP 1.89 IN 1979
SNOWFALL 2.7 IN. IN 1993
PEAK GUST 65e MPH N IN 1941
 
RECORDS FOR APRIL 28
HIGH 92 IN 1990
LOW 26 IN 1947
PRECIP 2.41 IN 1904
SNOWFALL 10.0 IN. IN 1987
PEAK GUST 69 MPH NE 1967
 
TODAY'S REPORT By: Stephanie Radner