BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, JANUARY 28, 2009 
ALL TIMES ARE IN EASTERN STANDARD TIME
 
SNOW CHANGES RAPIDLY TO SLEET THEN FREEZING
RAIN DURING THE HOUR FROM NOON TO 1 P.M.
AFTER AN ACCUMULATION OF 4.1 INCHES
 
Snow which began during the early hours of
today accumulated to 4.1 inches before quickly
changing to ice pellets and freezing rain just
after the noon hour.  The temperature, which was
19F as the snow first began, had risen to 30F by
1 p.m. and light freezing rain was causing the
formation of thin glaze.  Total snow on the
ground was 15 inches early this afternoon.
East winds were increasing and gusting just over
30 MPH just before one o'clock. 
 
Today's observations:
 
7 A.M.
Weather: Partial obscurement, broken stratocumulus, overcast
nimbostratus, snow obscuring 2/10 of sky, light snow occurring 
Temperature: 20F, Dew point: 18F, Wind: ENE at 11 kts
Sea-level pressure: 30.32 inches Hg, falling
Visibility: 3 miles, 4 miles east, light snow
6-hour minimum temperature: 19F
Snow depth on ground: 12 inches
BHO SA 1155 –X E17 BKN 30 OVC 3S- 266/20/18/0711/032/
S2 VSBY E 4 TOTAL NEW SNW PST 24 HRS 0.3 IN/ 8/52/
4/012 58020 ASOS 60003 ASOS 70003 MANUAL 6003/
MANUAL 70003 10021 20019 
 
10 A.M.
Weather: Obscurement with moderate snow and fog
Temperature: 25F, Dew point: 24F, Wind: E at 15 kts
Sea-level pressure: 30.19 inches Hg, falling
Visibility: 1/2 mile, moderate snow and fog    
3-hour precip: 0.12 inch
3-hour snowfall: 1.3 ins.
BHO SA 1455 W4 X 1/2SF 223/25/24/0915/019/
DRFTG SNW TOTAL NEW SNW PST 3 HRS 1.3 INS/
8//// 58043 ASOS 60010 MANUAL 6012/
 
1 P.M.  
Weather: Low overcast stratus fractus, light freezing
rain and fog, snow ended 12:25 p.m., ice pellets began
12:15 p.m. ended 12:50 p.m. freezing rain began 12:30 p.m.  
Temperature: 30F, Dew point: 29F, Wind: E at 17G27 kts,
Wind: Peak wind 27 kts E at 12:54 p.m.  
Sea-level pressure: 29.92 inches Hg, FALLING RAPIDLY,
Pressure: dropped 0.09 inch past hour
Visibility: 4 miles, light freezing rain and fog 
6-hour maximum temperature: 30F
6-hour precip: N/A
6-hour snowfall: 3.8 ins. 
BHO SA 1755 E4 OVC 4ZR-F 132/30/29/0917G27/992/
IPB15SE25ZRB30IPE50 THN GLZ PK WND 0927/54/ PRESFR
TOTAL NEW SNW PST 6 HRS 3.8 INS/ 8/7// 58091
ASOS 60041 MANUAL 6//// 10030 20020
 
WEATHER SUMMARY FOR TUESDAY, JANUARY 27
 
TEMPERATURE (DEGREES F)
MAX.....27    NORMAL.....34 
MIN.....14    NORMAL.....18
MEAN....21    NORMAL.....26
 
DEPARTURE FROM 30-YEAR NORMAL...............-5
TOTAL DEPARTURE FOR THE MONTH.............-118  [-4.6 DEGREES/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY.............44  DEPARTURE.........+5
TOTAL HEATING UNITS FOR THE MONTH...........1171  DEPARTURE.......+120
TOTAL HEATING UNITS FOR THE SEASON..........3411  DEPARTURE........+31
TOTAL HEATING UNITS LAST SEASON TO DATE.....3106  DIFFERENCE......+305
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............22  W  AT  7:42 A.M. 
                   AEROVANE.............21  W  AT  7:42 A.M.  
                   ASOS.................21  W  AT  7:59 A.M.  
                   DAVIS................20  W  AT  7:41 A.M.  
FASTEST MILE FOR YESTERDAY..............15  W  AT  7:46 A.M.   
MAXIMUM 2-MINUTE ASOS AVERAGE...........15  W  AT  8:00 A.M.   
MAXIMUM 2-MINUTE DAVIS AVERAGE..........16  W  AT  7:47 A.M.  
                   AVERAGE............ 7.7  W 
                   ASOS................7.2  
                   DAVIS...............7.0  W [270 deg]  
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.03  DEPARTURE.........-0.12
                         ASOS...............0.03
TOTAL PRECIPITATION FOR THE MONTH...........2.89  DEPARTURE.........-1.29
                         ASOS...............3.97 #
TOTAL PRECIPITATION FOR THE YEAR............2.89  DEPARTURE.........-1.29
                         ASOS...............3.97 #
# 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..........0.3   DEPARTURE.........-0.2
TOTAL SNOWFALL FOR THE MONTH...............20.9   DEPARTURE.........+7.4
TOTAL SNOWFALL FOR THE SEASON..............51.3   DEPARTURE........+24.2
 
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/+4/0.06/0/000/00 *     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 33/10/22/-4/0/0/518/92          47 W     Aero 48 MPH W
1/15 16/5/11/-15/0/0/000/00          20 NW
1/16 17/0/9/-17/0/0/557/98           26 W
1/17 19/1/10/-16/0/0/450/79          23 W
1/18 29/14/22/-4/0.58/9.5/000/00     24 E
1/19 32/19/26/+1/0.24/3.5/057/10     18 NW
1/20 30/17/24/-1/T/T/247/43          30 NW
1/21 23/9/16/-9/0/0/462/80           25 SW
1/22 31/14/23/-2/0/0/493/85          31 SW
1/23 39/24/32/+7/0/0/378/65          31 S
1/24 36/9/23/-3/0/0/280/48           40 W    Aero 42 MPH W
1/25 23/3/13/-13/0/0/532/91          25 SW
1/26 25/10/18/-8/0/0/535/91          17 W
1/27 27/14/21/-5/0/0/.../..          22 W
 
1/28 morning low temp: 19F; our normal low is now 18F
 
* 1/5 typo in sunshine data discovered:
  was 512/93 is corrected to 000/00
 
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 28
HIGH 59F IN 1916
LOW -9F IN 1888, 1924
PRECIP 2.18 INS. IN 1897
SNOWFALL 15.0 INS. IN 1897
PEAK GUST 78e MPH SSE IN 1977
 
RECORDS FOR JANUARY 29
HIGH 66F IN 2002
LOW -11F IN 1888
PRECIP 1.48 INS. IN 1973
SNOWFALL 8.0 INS. IN 1943
PEAK GUST 72 MPH NW IN 1973
 
TODAY'S REPORT PREPARED By: Robert Skilling