BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, APRIL 10, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
CLOUDS FILLED THE SKY QUICKLY THIS MORNING
TEMPERATURES STUCK NEAR 40 DEGREES
 
Unlike yesterday when there was plenty of bright sunshine, 
the cumulus and stratocumlus clouds formed and then  
quickly filled the sky to overcast by mid-morning.  
Today's high temperature is in the low 40's
after a 50-degree maximum temperature yesterday.  
 
Today's observations:
 
7 A.M.   
Weather: Broken clouds, sky clearing 
Temperature: 35F, Dew point: 22F, Wind: WNW at 9 kts 
Sea-level pressure: 29.94 inches Hg, rising
Visibility: 45 miles 
6-hour min. temp: 30F
BHO SA 1155 E50 BKN 250 BKN 45 140/35/22/2909/994/
FEW CU FRMG NE-E/ 8/801 53012 10035 20030  
  
10 A.M.
Weather: Overcast stratocumulus, breaks distant E-S
Temperature: 39F, Dew point: 20F, Wind: WNW at 11 kts  
Sea-level pressure: 29.96 inches of Hg, rising 
Visibility: 60 miles   
BHO SA 1455 E45 BKN E50 OVC 60 144/39/20/2911/996/ FEW LWR CU 
BINOVC DSNT E-S FEW PTCHS VIRGA/ 8/8// 53004
 
1 P.M.
Weather: Overast cumulus, stratocumulus, small break in overcast  
Temperature: 42F, Dew point: 20F, Wind: W at 11 kts
Sea-level pressure: 29.94 inches of Hg, falling 
Visibility: 60 miles   
6-hour max. temp. 42 deg.   
BHO SA 1755 E50 BKN 55 OVC 60 141/42/20/2711/994/ FEW LWR CU 
OCNL SML BINOVC SUN OCNL DMLY VSB/ 8/8// 58003 10042 20035 
 
WEATHER SUMMARY FOR MONDAY, APRIL 9
 
TEMPERATURE (DEGREES F)
MAX.....50    NORMAL.....53 
MIN.....30    NORMAL.....35
MEAN....40    NORMAL.....44
DEPARTURE FROM 30-YEAR NORMAL..........- 4
TOTAL DEPARTURE FOR THE MONTH..........-58 (-6.6 DEGREES/DAY) 
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY..........25   DEPARTURE........+ 4
TOTAL HEATING UNITS FOR THE MONTH.........259   DEPARTURE........+58 
TOTAL HEATING UNITS FOR THE SEASON.......5253   DEPARTURE.......-412
TOTAL HEATING UNITS LAST SEASON TO DATE..5129   DIFFERENCE......+124
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............36 W   AT 8:37 A.M. * 
                   AEROVANE............ 34 W   AT 8:37 A.M. 
                   ASOS.................32 W   AT 8:48 A.M. 
                   DAVIS................37 W   AT 8:17 A.M. 
FASTEST MILE FOR YESTERDAY..............26 W   AT 9:34 A.M.      
MAXIMUM 2-MINUTE ASOS AVERAGE...........26 W   AT 9:36 A.M. 
MAXIMUM 2-MINUTE DAVIS AVERAGE..........29 W   AT 9:36 A.M. 
AVERAGE WIND SPEED AND DIRECTION......17.6 W 
                    ASOS..............17.0  
                    DAVIS.............18.2 W [260 deg]
* last of several occurrences...
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE.....-0.15
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........1.90  DEPARTURE.....+0.55  
                         ASOS..............1.79    
TOTAL PRECIPITATION FOR THE YEAR..........13.64  DEPARTURE.....-1.34
                         ASOS.............13.43   
 
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......-0.8 
TOTAL SNOWFALL FOR THE SEASON..............27.6  DEPARTURE.....-30.3  
    
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   
4/9  50/30/40/-4/0/0/746/95          36 W
 
4/10 morning low temp. 30 deg; normal now 35 deg.  
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR APRIL 10
HIGH 83 IN 1922
LOW 20 IN 1985
PRECIP 2.40 IN. IN 1935
SNOWFALL 10.1 IN. IN 1996
PEAK GUST 66 MPH WNW IN 1967
 
RECORDS FOR APRIL 11
HIGH 78 IN 1945
LOW 19 IN 1909
PRECIP 1.72 IN. IN 2003
SNOWFALL 9.5 IN. IN 1958
PEAK GUST 65 MPH NW IN 1963
 
TODAY'S REPORT By: Robert Skilling