BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
  
DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, APRIL 19, 2008
ALL TIMES ARE IN EASTERN STANDARD TIME UNLESS NOTED

WARM AND DRY CONDITIONS CONTINUE WITH FULL SUNSHINE...
VERY STRONG TEMPERATURE INVERSION FORMED THIS MORNING...
It will be another dry day with close to full sunshine
and warm temperatures.  The low temperature on the 
summit of 60 this morning was 24 degrees warmer than
the low of 36 recorded at the nearby, low-lying Norwood
Airport about 3.5 miles to the SW and roughly 500 feet
below the summit.  The low of 60 is slightly higher than
the present record high minimum for this date of 58 set
in 1976, though it may get cooler than this by midnight. 
The dew point has climbed to the upper 30s today, though
the relative humidity remains low also in the 30s. The
fire danger is begining to rise due to the dry conditions 
this week, which are expected to continue into next week. 
Friday sunshine was about 88 percent after three straight
days of 100 percent. 

 
Today's observations:

8 A.M. EDT
Weather: Clear, few cirrus and altocumulus
Temperature: 63F, Dew point: 31F  Wind: ENE at 5 kts
Sea-level pressure: 30.08 inches Hg, rising
Visibility: 40 miles
6-hour min temp: 60F
24-hour precipitation: none 
BHO SA 1155 CLR 40 185/63/31/0705/008/ FEW CI NNE FEW AC 
DSNT SSW K LYR BLO INVSN SW-NNE HAZY WND LGT/ 8/031 51017 
10063 20060

11 A.M. EDT
Weather: Clear
Temperature: 67F, Dew point: 37F, Wind: NE at 6 kts 
Wind: Light and variable 
Sea-level pressure: 30.11 inches Hg, rising
Visibility: 35 miles, hazy  
BHO SA 1455 CLR 35 195/67/37/0406/011/ HAZY WND LGT AND VRB/ 
51010

2 P.M. EDT
Weather: Clear
Temperature: 63F, Dew point: 39F, Wind: NE at 12 kts 
Sea-level pressure: 30.11 inches Hg, steady
Visibility: 35 miles, hazy     
6-hourly max.temp: 70F  
BHO SA 1755 CLR 35 195/63/39/0412/011/ HAZY/ 50000 10070 20062


WEATHER SUMMARY FOR FRIDAY, APRIL 18

TEMPERATURE (DEGREES F)
MAX.....72    NORMAL.....56
MIN.....40    NORMAL.....38
MEAN....56    NORMAL.....47
DEPARTURE FROM 30-YEAR NORMAL...........+9 
TOTAL DEPARTURE FOR THE MONTH..........+33 [+1.6 DEGREES/DAY] 

HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY.............9  DEPARTURE....... -9
TOTAL HEATING UNITS FOR THE MONTH...........342  DEPARTURE.......-33 
TOTAL HEATING UNITS FOR THE SEASON.........5479  DEPARTURE......-360
TOTAL HEATING UNITS LAST SEASON TO DATE....5481  DIFFERENCE.......-2  
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............23 NW  AT  6:21 A.M.   
                   AEROVANE.............21 NNW AT  7:07 A.M. *   
                   ASOS.................21 ENE AT 11:56 A.M.    
                   DAVIS................21 NNW AT  3:01 A.M.     
FASTEST MILE FOR YESTERDAY..............18 NW  AT  6:24 A.M.    
MAXIMUM 2-MINUTE ASOS AVERAGE...........17 N   AT  6:59 A.M. 
MAXIMUM 2-MINUTE DAVIS AVERAGE..........19 NW  AT  3:03 A.M.    
AVERAGE WIND SPEED AND DIRECTION......10.5 NE
                   ASOS................9.6    
                   DAVIS..............10.3 N  [003 deg]  

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00   DEPARTURE......-0.14  
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........1.52   DEPARTURE......-1.16
                         ASOS..............1.66 
TOTAL PRECIPITATION FOR THE YEAR..........19.12   DEPARTURE......+2.81
                         ASOS.............21.54 #
# Includes erroneous ASOS precipitation data on 2/13/08.

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0    DEPARTURE......-0.1
TOTAL SNOWFALL FOR APRIL...................0.0    DEPARTURE......-1.9
TOTAL SNOWFALL FOR THE SEASON.............66.5    DEPARTURE......+7.6

PRELIMINARY CLIMATE SUMMARY FOR APRIL 2008 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane recording wind system when significant
TSTM: Thunderstorm day
....: Data not yet available, records not finalized

4/1  59/50/55/+14/0.20/0/000/00    54 S    Aero 58 MPH SSW
4/2  47/31/39/-3/0/0/745/97        52 W    Aero 51 MPH W
4/3  52/27/40/-2/0/0/648/84        37 SSW 
4/4  43/34/39/-3/0.71/0/000/00     35 E
4/5  51/37/44/+1/0.06/0/093/12     21 W
4/6  40/36/38/-5/0.09/0/000/00     36 NE 
4/7  39/34/37/-6/0/0/172/22        35 NE    Aero 36 MPH NE
4/8  47/30/39/-5/0/0/627/80        22 NE
4/9  59/33/47/+3/0/0/150/19        29 S    
4/10 71/44/58/+14/T/0/624/79       34 W
4/11 54/40/47/+2/0.03/096/13       24 SE 
4/12 70/43/57/+12/0.43/0/342/43    40 WNW   Aero 42 WNW
4/13 47/34/41/-4/T/0/104/13        30 NW 
4/14 53/30/42/-4/0/0/625/78        29 NW  
4/15 57/33/45/-1/0/0/803/100       23 SSE 
4/16 64/39/52/+6/0/0/806/100       24 SSE
4/17 64/14/53/+6/0/0/810/100       23 NE
4/18 70/42/56/+9/0/0/.../..        23 NW

4/19 morning low temp. 60F; our normal low is now 38F

NEW DAILY RECORDS FOR APRIL 2008
None to date.

DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):

RECORDS FOR APRIL 19
HIGH 94 IN 1976 [RECORD FOR MONTH]
LOW 21 IN 1890
PRECIP 1.71 IN 1969
SNOWFALL 6.0 IN. IN 1887
PEAK GUST 66 MPH E IN 1984

RECORDS FOR APRIL 20
HIGH 88 IN 1927
LOW 18 IN 1897
PRECIP 1.14 IN 1972
SNOWFALL 2.5 IN. IN 1904, 1972
PEAK GUST 76 MPH WNW IN 1963

TODAY'S REPORT PREPARED By: Mike Iacono