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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, FEBRUARY 11, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

TEMPERATURES DROP AS WINDS SHIFT TO THE NE WITH RAIN... 

Light winds this morning picked up in intensity
as they shifted towards the northeast.  This caused
temperatures to drop from the mid 40s at the 7 o'clock
observation to the mid 30s by the 10 o'clock 
observation and stayed there through the 1 PM observation.  
Even with this drop temperatures were still above 
average today.    

The day began with light rain and that rain continued
throughout the day.  Visibility was obscured all day by 
fog and did not get above 1/2 mile under rainy conditions, 
dropping to just 1/4 of a mile by the 1 o'clock observation.  
 

Today's Observations:

7 A.M.
Weather: Rain and Fog  
Temperature: 44F; Dew Point: 44F; Wind: NE at 4 kts
Wind: Light
Sea-level pressure: 30.07 ins. Hg, falling, then rising    
Visibility: 1/2 mile
6-hr Max temp: 46F
6-hr Min temp: 44F
24-hr precip: 0.041 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1155 W2 X 1/2F 185/44/44/0504/007/ 8//// 53015 
MANUAL 70041 ASOS 70042 10046 20044 

10 A.M.
Weather: Rain and Fog
Temperature: 36F; Dew Point: 36F; Wind: ENE at 13 kts
Sea-level pressure: 30.09 ins. Hg, rising, then falling but higher
Visibility: 1/2 mile 
3-hr precip: 0.12 ins.
3-hr snowfall: 0.0 ins.  
BHO SA 1455 W2 X 1/2F 190/36/36/0613/009/ 8//// 50005 
MANUAL 60012 ASOS 60012  
 
1 P.M.
Weather: Rain and Fog
Temperature: 36F; Dew Point: 36F; Wind: ENE at 11G17  kts
Sea-level pressure: 30.03 ins. Hg, falling, then more quickly 
Visibility:  1/4 miles, distant fog in all directions
6-hr Max temp: 44F
6-hr Min temp: 36F
6-hr precip: 0.31 ins
6-hr snowfall: 0.0 ins.
Snow depth: 0 in.
BHO SA 1755 W2 X 1/2F 170/36/36/0711G17/003/ 8//// 58020 
MANUAL 60031 ASOS 60032 10044 20036 

SUMMARY FOR SATURDAY, FEBRUARY 10, 2018

TEMPERATURE (DEGREES F)
MAX.....51   NORMAL.....35
MIN.....28   NORMAL.....18
MEAN....40   NORMAL.....27

DEPARTURE FROM 30-YEAR NORMAL.............................+13
TOTAL DEPARTURE FOR THE MONTH.............................+19 [+1.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............25   DEPARTURE.........-13
TOTAL HEATING UNITS FOR THE MONTH............367   DEPARTURE.........-20
TOTAL HEATING UNITS FOR THE SEASON..........3688   DEPARTURE........-230
TOTAL HEATING UNITS LAST SEASON TO DATE.....3389   DIFFERENCE.......+299

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................31 S AT  1:27 A.M.* 
                   AERO.........................30 S AT  1:23 A.M.
                   ASOS.........................32 S AT  1:25 A.M.
                   DAVIS........................30 M AT  1:24 A.M.** RMY 31 
FASTEST MILE FOR YESTERDAY......................23 S AT  1:23 A.M.   
MAXIMUM 2-MINUTE ASOS AVERAGE...................24 S AT  4:28 A.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE..................22 M AT 12:58 A.M.**
AVERAGE WIND SPEED AND DIRECTION..............16.5 S
                   ASOS.......................16.6 
                   DAVIS......................15.3 ** 

* Last of several occurrences
** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.41  DEPARTURE......+0.27
                         ASOS..............0.42
TOTAL PRECIPITATION FOR THE MONTH..........2.02  DEPARTURE......+0.67
                         ASOS..............2.11  
TOTAL PRECIPITATION FOR THE YEAR...........8.02  DEPARTURE......+2.32
                         ASOS..............8.69

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE........-0.5
TOTAL SNOWFALL FOR THE MONTH................3.6  DEPARTURE........-1.3
TOTAL SNOWFALL FOR THE SEASON..............38.1  DEPARTURE.........0.0

PRELIMINARY CLIMATE SUMMARY FOR FEBRUARY 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

2/1  45/27/36/+10/..../0.0/.../..      36 SSW AERO 35 SSW RMY N/A 
2/2  34/08/21/-5/..../.../.../..       43 WNW AERO 46 WNW RMY 46 
2/3  25/04/15/-11/0.00/0.0/.../..      26 S   AERO 24 S   RMY 30 
2/4  45/23/34/+8/.../T/.../..          31 SSE AERO 29 S   RMY 30
2/5  46/19/33/+7/0.00/0.0/.../..       47 WNW AERO 47 WNW RMY 44
2/6  31/17/24/+2/T/T/.../..            26 SSW AERO 23 SSW RMY 23 
2/7  42/21/32/+5/0.62/1.1/000/00       45 SW  AERO 46 SW  RMY 47
2/8  30/20/25/-2/0.00/0.0/.../..       38 WNW AERO 38 WNW RMY N/A
2/9  30/16/23/-4/0.00/0.0/.../..       28 S   AERO 25 S   RMY N/A
2/10 51/28/40/+13/.../0.0/.../..       31 S   AERO 30 S   RMY 31

2/11 Low temp since midnight is 36F; normal low is now 18F

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

RECORDS FOR FEBRUARY 11
HIGH 60F IN 1981
LOW -10F IN 1899
PRECIP 1.07 INCHES IN 1955
SNOWFALL 9.6 INCHES IN 1933
PEAK GUST 95 MPH S IN 1981

RECORDS FOR FEBRUARY 12
HIGH 56F IN 1999
LOW -14F IN 1914
PRECIP 4.85 INCHES IN 1886 [RECORD FOR MONTH]
SNOWFALL 15.0 INCHES IN 2006
PEAK GUST 70 MPH E IN 1985

TODAY'S REPORT PREPARED BY: Robert Millette