BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, JANUARY 23, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

THICK FOG AND HEAVY AFTERNOON RAIN...

The Observatory continues to be socked in the fog
for another day. Rain also continued today, starting
in the morning as a light drizzle and become heavy 
after 1:00 P.M. So far today since we have measured 
0.63 ins by 1:00 P.M.
Pressure began to fall rapidly after a wind shift 
from NE-SE. As the pressure fell the wind began to
pick up and we have had a peak gust so far of 
36 kts (41 MPH) just before 2:00 P.M. Temperatures 
also rapidly rose and continued to rise after the 
wind shift with a maximum of 49F by 1:00 P.M. This 
is already 15 degrees above the daily normal of 34F.
Due to the fog, visibility was poor with a max of 
.25 miles at 10:00 A.M. 
   
Today's Observations:

7 A.M.
Weather: Very light drizzle and fog
Temperature: 34F; Dew Point: 34F; Wind: ENE at 9 kts
Sea-level pressure: 29.96 ins. Hg, falling then steady
Visibility: 1/8 mile
6-hr Max temp: 38F
6-hr Min temp: 33F
24-hr precip: 0.11 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1155 W3 X 1/8L-F 145/34/34/0609/996/ PCPN VRY LGT/ 
8//// 56023 MANUAL 70011 ASOS 70010 10038 20033

10 A.M.
Weather: Light rain and fog, overcast nimbostratus 
Temperature: 40F; Dew Point: 40F; Wind: SE at 9 kts
Sea-level pressure: 29.84 ins. Hg, falling, then more quickly 
Visibility: 1/4 mile 
3-hr precip: 0.10 ins.
3-hr snowfall: 0.0 ins. 
BHO SA 1455 E4 OVC 1/4R-F 105/40/40/1309/984/ 8/6// 58040 
MANUAL 6010/ ASOS 60008 

1 P.M.
Weather: Moderate rain and fog, overcast nimbostratus 
Temperature: 49F; Dew Point: 49F; Wind: S at 18G26 kts,
Peak wind: 27 kts (31 MPH) S at 12:37 P.M.
Sea-level pressure: 29.65 ins. Hg, falling, then more quickly 
Visibility: 1/8 mile 
6-hr precip: 0.63 ins.
6-hr snowfall: 0.0 ins.
6-hr Max temp: 49F
6-hr Min temp: 33F
Snow depth: 0 ins. 
BHO SA 1755 E4 OVC 1/8RF 039/49/49/1718G26/965/ PK WND 
1727/37 PRESFR/ 8/6// 58066 MANUAL 6063/ 60067 10049 20033 

SUMMARY FOR MONDAY, JANUARY 22, 2018

TEMPERATURE (DEGREES F)
MAX.....37   NORMAL.....34
MIN.....34   NORMAL.....17
MEAN....36   NORMAL.....25

DEPARTURE FROM 30-YEAR NORMAL..........................+11
TOTAL DEPARTURE FOR THE MONTH..........................-24 [-1.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............29  DEPARTURE.........-11
TOTAL HEATING UNITS FOR THE MONTH............893  DEPARTURE.........+24
TOTAL HEATING UNITS FOR THE SEASON..........3015  DEPARTURE........-158
TOTAL HEATING UNITS LAST SEASON TO DATE.....2747  DIFFERENCE.......+268

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................21 E AT 8:11 P.M.
                   AERO.........................16 E AT 8:11 P.M.
                   ASOS.........................20 E AT 8:12 P.M.
                   DAVIS........................17 E AT 4:19 P.M. RMY N/A 
FASTEST MILE FOR YESTERDAY......................14 E AT 8:12 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE...................15 E AT 8:08 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE..................13 E AT 8:12 P.M.
AVERAGE WIND SPEED AND DIRECTION...............7.0 NE
                   ASOS........................7.7 
                   DAVIS.......................6.6 NE

*Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.11  DEPARTURE......-0.03
                         ASOS..............0.10
TOTAL PRECIPITATION FOR THE MONTH..........4.31  DEPARTURE......+1.19
                         ASOS..............4.73
TOTAL PRECIPITATION FOR THE YEAR...........4.31  DEPARTURE......+1.19
                         ASOS..............4.73

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE........-0.6
TOTAL SNOWFALL FOR THE MONTH...............19.3  DEPARTURE........+7.0
TOTAL SNOWFALL FOR THE SEASON..............28.6  DEPARTURE........+0.3

PRELIMINARY CLIMATE SUMMARY FOR JANUARY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST
AERO: Aerovane wind recording system gust
RMY:  R.M. Young wind gust recording system
TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized
M:    Missing data

1/01 11/-5/3/-24/0.00/0.0/538/98        30 NW  AERO 30 NW  RMY 31
1/02 15/-2/7/-20/0.00/0.0/402/73        26 W   AERO 25 W   RMY 26  
1/03 28/11/20/-6/0.00/0.0/430/78        23 WSW AERO 20 WSW RMY N/A
1/04 28/18/23/-3/1.66/16.5/000/00       54 NNW AERO 60 NNW RMY 64
1/05 18/2/10/-16/0.00/0.0/431/78        53 W   AERO 53 W   RMY 57
1/06 10/-2/4/-22/0.00/0.0/554/100       43 WSW AERO 47 WSW RMY 47
1/07 14/-8/3/-23/0.00/0.0/549/99        37 WNW AERO 35 WNW RMY N/A 
1/08 33/14/24/-2/0.02/T/006/01          40 S   AERO 40 S   RMY 42 
1/09 40/25/33/+7/T/T/356/64             37 W   AERO 35 W   RMY 33
1/10 36/20/28/+3/0.00/0.0/553/99        30 W   AERO 30 W   RMY N/A
1/11 50/32/41/+16/0.00/0.0/056/10       33 S   AERO 32 S   RMY 34
1/12 60/45/53/+28/..../0.0/011/02       56 S   AERO 56 S   RMY 55
1/13 60/17/39/+14/..../0.0/265/47       58 SSW AERO 60 SSW RMY 62
1/14 21/11/16/-9/0.00/0.0/350/62        30 NW  AERO 30 NW  RMY N/A
1/15 18/11/15/-10/0.02/0.5/000/00       23 NNW AERO 21 N   RMY 23
1/16 31/18/25/0/0.00/0.0/153/27         17 SSE AERO 15 SSE RMY N/A 
1/17 32/29/31/+6/0.23/2.3/.../00        20 SE  AERO 17 SE  RMY N/A
1/18 29/16/23/-2/0.00/0.0/.../..        24 NW  AERO 23 NW  RMY 26 
1/19 34/17/26/+1/0.00/0.0/.../..        22 SSW AERO 20 SSW RMY N/A
1/20 45/27/36/+11/0.00/0.0/.../..       38 WSW AERO 37 WSW RMY 39 
1/21 47/34/41/+16/0.00/0.0/.../..       22 W   AERO 21 W   RMY N/A
1/22 37/34/36/+11/..../0.0/000/00       21 E   AERO 16 E   RMY N/A

1/23 Low temp since midnight is 33F; normal low is now 17F

DAILY RECORDS FOR JANUARY 2018

01/04/18: NEW DAILY RECORD MAXIMUM SNOWFALL OF 16.5 INS. 
          PREVIOUS RECORD WAS 8.6 INS. SET IN 1923 AND 
          TIED IN 1942 

01/07/18: DAILY RECORD LOW MINIMUM TEMPERATURE OF -8F,
          PREVIOUS RECORD OF -7F WAS SET IN 1896

01/12/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 45F,
          PREVIOUS RECORD OF 42F WAS SET IN 2017

          DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 60F,
          PREVIOUS RECORD OF 59F WAS SET IN 2017

01/13/18: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 60F,
          PREVIOUS RECORD OF 57F WAS SET IN 1890 AND
          TIED IN 1932 

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

RECORDS FOR JANUARY 23
HIGH 62F IN 1906
LOW -10F IN 1976
PRECIP 2.40 INS. IN 1935
SNOWFALL 14.6 INS. IN 1966
PEAK GUST 85 MPH S IN 1992

RECORDS FOR JANUARY 24
HIGH 60F IN 1967
LOW -12F IN 1907
PRECIP 2.04 INS. IN 1998
SNOWFALL 11.3 INS. IN 1935
PEAK GUST 82 MPH S IN 1996

TODAY'S REPORT PREPARED BY: Kaitlin Ann Geagan