BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, JANUARY 14, 2009
ALL TIMES ARE IN EASTERN STANDARD TIME
 
A FEW HOURS OF LIGHT RAIN, SOME SLEET PRECEDED ARCTIC ADVANCE
WEST WINDS GUST TO 45 MPH AS TEMPERATURES FELL RAPIDLY
WINTER SNOWFALL TOTAL TO DATE 38 INCHES--AVERAGE TO DATE 20 INS.  
 
Late yesterday temperatures edged slightly above freezing
reaching a high of 34 degrees at 10:30 p.m. Light rain
mixed with some sleet fell for several hours from mid-evening
to just before midnight amounting to 0.04 inch.  Then, just
after 2 a.m.,the Arctic air began arriving with rapidly
increasing west winds. A peak gust to 47 MPH was recorded
just before 6 a.m. but winds were gusting 30 to 40 MPH
from 2:10 a.m. through the morning.  Temperatures fell from
a high of 33F at 1 a.m. to 14F just after 8 a.m. Dew points  
continued to fall throughout this morning reaching the mid-single
numbers below zero by late morning.
 
Our winter snowfall since December 1 is up to 38 inches or
18 inches more than average, the result of one of our snowiest
Decembers.  However, consider this, the last time we recorded
more snowfall through mid-January was in the winter of 1995-96
when the seasonal total had reached 68.5 inches at mid-January! 
That season went on to end up with a total of 144 inches,
the all-time record.    
 
7 A.M.
Weather: Clear, few stratocumulus along shore NE-E and offshore distant
SE-S, some stratocumulus with virga trails distant ESE, altocumulus
later along horizon distant NE-ESE 
Temperature: 16F, Dew point: 3F, Wind: W at 19G33 kts,
Wind: Peak wind gust from west at 35 kts at 6:23 a.m.,
Wind: direction variability WSW-NW
Sea-level pressure: 29.78 inches Hg, RISING RAPIDLY  
Visibility: 55 miles
6-hour minimum temperature: 16F
24-hour precip: 0.04 in.
24-hour snowfall: trace
Snow depth on ground: 7 inches
BHO SA 1155 CLR 55 083/16/3/2819G33/978/
FEW SC ENE-ESE ALGSHR SC/VIRGA TRLS DSNT ESE
SC OFFSHR DSNT SE-S AC LYR ALG HRZN DSNT NE-ESE
PK WND 2835/23/ WND 25V31 PRESRR/ 8/570 4/007
53048 MANUAL 70004 ASOS 70004 10033 20016  
 
10 A.M.
Weather: Clear, few cumulus fractus distant ESE
Temperature: 15F, Dew point: -3F, Wind: W at 18G29 kts,
Peak wind gust 32 kts WNW at 9:17 a.m.,
Wind: direction variability WSW-NW 
Sea-level pressure: 29.93 inches Hg, rising
Visibility: 75 miles
BHO SA 1455 CLR 75 137/15/-3/2818G29/993/
FEW CUFRA DSNT ESE PK WND 2932/23 WND 25V31/
8/100 51054
 
1 P.M.  
Weather: Thin overcast cirrus, layer advancing with clear
sky visible NNWN-ESE
stratocumulus NE-SE-SSW, sun occasionally dimly visible
Temperature: 19F, Dew point: -3F, Wind: W at 11G20 kts,
Wind: Peak wind gust 27 kts W at 12:02 P.M.,
Wind: direction variability WSW-NW
Sea-level pressure: 29.92 inches Hg, falling
Visibility: 75 miles
6-hour maximum temperature: 19F
BHO SA 1755 250 –SCT 300 –OVC 75 133/19/-3/2711G20/992/
THN CI LYR ADVCNG CLR SKY NNW-ESE PK WND 2827/02/ WND 24V31/
8/006 58004 10019 20014
 
WEATHER SUMMARY FOR TUESDAY, JANUARY 13
 
TEMPERATURE (DEGREES F)
MAX.....34    NORMAL.....34 
MIN.....18    NORMAL.....18
MEAN....25    NORMAL.....26
 
DEPARTURE FROM 30-YEAR NORMAL...............-1
TOTAL DEPARTURE FOR THE MONTH..............-29  [-2.4 DEGREES/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY.............40  DEPARTURE.........+1
TOTAL HEATING UNITS FOR THE MONTH............531  DEPARTURE........+30
TOTAL HEATING UNITS FOR THE SEASON..........2771  DEPARTURE........-59
TOTAL HEATING UNITS LAST SEASON TO DATE.....2551  DIFFERENCE......+220
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............25 SE  AT  5:34 P.M.   
                   AEROVANE.............23 SE  AT  5:35 P.M.  
                   ASOS.................24 SE  AT  5:34 P.M.       
                   DAVIS................26 SE  AT  5:46 P.M.        
FASTEST MILE FOR YESTERDAY..............20 SE  AT  5:33 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE...........18 SE  AT  5:33 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE..........21 SE  AT  5:33 P.M.           
                   AVERAGE............11.2 SE
                   ASOS...............10.7
                   DAVIS..............11.3 SSE [150 deg]  
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.04  DEPARTURE.........-0.12
                         ASOS...............0.04
TOTAL PRECIPITATION FOR THE MONTH...........2.04  DEPARTURE.........+0.04
                         ASOS...............3.02 #
TOTAL PRECIPITATION FOR THE YEAR............2.04  DEPARTURE.........+0.04
                         ASOS...............3.02 #
# Includes erroneous ASOS precipitation data on 1/1/09 and 1/2/09
 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........trace  DEPARTURE.........-0.5
TOTAL SNOWFALL FOR THE MONTH................7.6   DEPARTURE.........+1.1
TOTAL SNOWFALL FOR THE SEASON..............38.0   DEPARTURE........+17.9
 
PRELIMINARY CLIMATE SUMMARY FOR JANUARY 2009 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane recording wind system gust when significant
   TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized
 
1/1  16/1/9/-18/0/0/538/98           44 WNW   Aero 44 MPH WNW
1/2  32/9/21/-6/0/0/005/01           28 S
1/3  32/21/27/0/T/T/539/98           43 WNW   Aero 44 MPH WNW
1/4  35/17/26/-1/0/0/512/93          36 W     Aero 33 MPH W
1/5  36/26/31/+4/0.06/0/512/93       30 W   
1/6  33/21/27/+1/0/0/183/33          27 W 
1/7  36/26/31/+5/1.26/0.8/000/00     46 NE    Aero 45 MPH NE
1/8  38/21/30/+4/0.01/0.1/389/70     47 W     Aero 45 MPH W
1/9  25/16/21/-5/0/0/546/98          37 W     Aero 36 MPH W
1/10 24/11/18/-8/0.10/1.0/329/59     28 W
1/11 31/19/25/-1/0.55/5.3/000/00     30 NW
1/12 27/18/23/-3/0.02/0.4/410/73     24 WNW
1/13 34/16/25/-1/0.04/T/107/19       25 SE
 
1/14 morning low temp: 16F; our normal low is now 18F
    
NEW DAILY RECORDS FOR JANUARY 2009...
 
..NONE..
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR JANUARY 14
HIGH 65F IN 1995
LOW -12F IN 1914
PRECIP 1.45 INS. IN 2008
SNOWFALL 10.3 INS. IN 2008
PEAK GUST 68 MPH WNW IN 1976, S IN 2005
 
RECORDS FOR JANUARY 15
HIGH 64F IN 1995
LOW -16F IN 1957 [RECORD FOR MONTH]
PRECIP 2.63 INS. IN 1958
SNOWFALL 8.8 INS. IN 1983
PEAK GUST 69e MPH SE IN 1940
 
TODAY'S REPORT PREPARED By: Robert Skilling