BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
  
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, DECEMBER 19, 2007
ALL TIMES ARE IN EASTERN STANDARD TIME
 
TEMPERATURES RISE ABOVE FREEZING TODAY 
A LITTLE SUNSHINE THIS MORNING
 
There was some melting of the snow and ice today 
as temperatures rose through the 30's with very 
little in the way of sunshine. 
  
Today's observations:
 
7 A.M.   
Weather: Broken altocumulus, overcast dense cirrus,
thin spots in overcast 
Temperature: 27F, Dew point: 23F, Wind: SE at 10 kts
Sea-level pressure: 30.32 inches Hg, steady   
Visibility: 15 miles, 20 SE, thin fog below inversion, hazy
6-hour min temp: 24F 
24-hour precip: 0.00 ins. 
24-hour snowfall: 0.0 ins. 
Snow on ground: 10 inches 
BHO SA 1155 E110 BKN 200 OVC 15 266/27/23/1310/032/ DENS CI 
THN SPTS IOVC PTCHS THN F BLO INVSN HAZY VSBY SE 20 WND GRDLY BACKING/
8/072 4/010 53002 10028 20024  
   
10 A.M.
Weather: Overcast dense high cirrus/cirrostratus clouds   
Temperature: 32F, Dew point: 27F, Wind: SSE at 10 kts
Sea-level pressure: 30.32 inches Hg, steady  
Visibility: 10 miles, hazy    
BHO SA 1455 100 SCT E200 BKN 250 OVC 10 267/32/27/1510/032/
DENS CI/CS SUN DMLY VSB THN FG HZY ALQDS/ 8/017 53001
 
1 P.M.
Weather: Scattered stratocumulus, high overcast cirrus/cirrostratus  
Temperature: 37F, Dew point: 30F, Wind: S at 4 kts
Sea-level pressure: 30.24 inches Hg, falling 
Visibility: 10 miles, lower east thru south, hazy all directions   
6-hourly max. temp: 38F  
BHO SA 1755 20 SCT 100 SCT E220 BKN 250 OVC 10 240/37/30/1704/024/ 
SC E-S VSBY LWR E-S HAZY/ 8/577 56027 10038 20026 
 
WEATHER SUMMARY FOR TUESDAY, DECEMBER 18
 
TEMPERATURE (DEGREES F)
MAX.....31    NORMAL.....38 
MIN.....10    NORMAL.....23
MEAN....21    NORMAL.....30
DEPARTURE FROM 30-YEAR NORMAL...........-9 
TOTAL DEPARTURE FOR THE MONTH.........-115 [-6.6 DEGREES/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY............44  DEPARTURE......+10  
TOTAL HEATING UNITS FOR THE MONTH...........691  DEPARTURE.....+120 
TOTAL HEATING UNITS FOR THE SEASON.........1771  DEPARTURE..... -89
TOTAL HEATING UNITS LAST SEASON TO DATE....1498  DIFFERENCE....+273
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............23 W  AT 12:08 A.M.  
                   AEROVANE.............22 W  AT 12:08 A.M.   
                   ASOS.................21 W  AT 12:08 A.M.  
                   DAVIS................22 W  AT 12:03 A.M.   
FASTEST MILE FOR YESTERDAY............. 18 W  AT 12:08 A.M.  
MAXIMUM 2-MINUTE ASOS AVERAGE...........17 W  AT 12:09 A.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE..........18 W  AT 12:00 A.M.  
AVERAGE WIND SPEED AND DIRECTION..... .9.8 W  
                   ASOS................9.8 W           
                   DAVIS..............10.6 WSW [250 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..........3.72  DEPARTURE....+1.09
                         ASOS..............3.83  
TOTAL PRECIPITATION FOR THE YEAR..........42.56  DEPARTURE....-6.73
                         ASOS.............42.05  
 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE.....-0.4
TOTAL SNOWFALL FOR THE MONTH...............20.6  DEPARTURE....+15.1
TOTAL SNOWFALL FOR THE SEASON..............21.4  DEPARTURE....+13.0
 
PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2007...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
 
12/1  33/15/24/-12/0/0/493/88       54 WNW 
12/2  24/15/20/-16/0.03/0.3/000/00  28 WNW 
12/3  38/23/31/-4/0.62/1.7/000/00   47 W 
12/4  27/17/22/-13/T/T/111/20       48 W       
12/5  29/17/23/-12/T/T/244/44       23 WNW
12/6  28/15/22/-12/0/0/554/100      31 WNW
12/7  34/21/28/-6/0.07/0.7/000/00   24 SSW
12/8  41/25/33/0/0/0/452/82         32 W
12/9  33/25/29/-4/0.08/T/000/00     16 NW  
12/10 30/26/28/-5/0.10/0/000/00     18 N 
12/11 36/22/29/-3/0.09/0/258/47     25 S
12/12 44/22/36/+4/T/0/88/16         39 W
12/13 29/20/25/-7/1.08/9.2/000/00   24 ENE
12/14 37/20/29/-2/0.02/0.2/038/07   28 WSW
12/15 28/15/22/-9/0/0/.../..        31 WNW  
12/16 43/23/33/+2/1.62/8.5/000/00   54 NE 
12/17 32/15/24/-7/0/0/.../..        62 W
12/18 31/10/21/-9/0/0/.../..        20 W
 
12/19 morning low temp. 24F; our normal low is now 23F
      total snow and ice on the ground 10 inches 
 
NEW DAILY RECORDS FOR DECEMBER 2007: 
Dec 13: Record daily snowfall of 9.2 inches surpasses previous 
record of 9.0 inches in 1902.
Dec.16: Record daily snowfall of 8.5 inches surpasses previousE
record of 7.0 inches in 1896.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR DECEMBER 19
HIGH 59 IN 1899
LOW -1 IN 1919
PRECIP 2.06 INS. IN 1986
SNOWFALL 14.1 INS. IN 1945
PEAK GUST 68 NE IN 1986
 
RECORDS FOR DECEMBER 20
HIGH 61 IN 1957
LOW -16 IN 1942
PRECIP 1.69 INS. IN 1936
SNOWFALL 8.3 INS. IN 1995
PEAK GUST 75 MPH S IN 2002
 
TODAY'S REPORT PREPARED By: Robert Skilling