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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, MARCH 20, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

ANOTHER GREAT VISIBILITY DAY WITH INCREASING CLOUDS...
VERNAL EQUINOX (FIRST DAY OF SPRING) WAS TODAY AT 12:15 PM...

Today we observed increasing clouds and a visibility
of 80 miles. Winds became light and variable at noontime.
The low temperature since midnight was 18F, which is
10 degrees below the normal of 28F.
So far today we have reached a max of 38F. Pressure began
to decrease between 10:00 A.M. and 1:00 P.M. 

Today's Observations:

7 A.M.
Weather: Scattered cirrus
Temperature: 22F; Dew Point: 8F; Wind: NNW at 10G16 kts
Sea-level pressure: 29.96 ins. Hg, rising, then more slowly           
Visibility: 80 miles
6-hr Max temp: 24F
6-hr Min temp: 18F
24-hr precip:  0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 10 ins.
BHO SA 1155 250 SCT 80 147/22/08/3309G18/996/ 8/002 4/010 50000 
10024 20018 

10 A.M.
Weather: Scattered cirrus
Temperature: 33F; Dew Point: 11F; Wind: NW at 5G11 kts,
Wind: Light 
Sea-level pressure: 29.96 ins. Hg, rising then falling 
Visibility: 80 miles
3-hr precip:  0.00 ins.
3-hr snowfall: 0.0 ins.    
BHO SA 1455 250 SCT 80 147/33/11/3205G11/996/ WND LGT/ 8/002 50000

1 P.M.
Weather: Broken altostratus, few cirrus ENE-NNW
Temperature: 38F; Dew Point: 17F; Wind: SSW (Estimated) at 2 kts,
Wind: Light and variable
Sea-level pressure: 29.93 ins. Hg, falling, then more steadily
Visibility: 80 miles
6-hr Max temp: 38F
6-hr Min temp: 22F
6-hr precip:   0.00 ins.
6-hr snowfall: 0.0 ins.
Snow depth: 9 ins.
BHO SA 1755 E200 BKN 80 137/38/17/E2102/993/ FEW CI ENE-NNW WND 
L/V/ 8/021 4/009 57010 10038 20022
 
SUMMARY FOR MONDAY, MARCH 19, 2018

TEMPERATURE (DEGREES F)
MAX.....35   NORMAL.....45
MIN.....13   NORMAL.....27
MEAN....24   NORMAL.....36

DEPARTURE FROM 30-YEAR NORMAL...........................-12
TOTAL DEPARTURE FOR THE MONTH...........................-20 [-1.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............41   DEPARTURE.........+12
TOTAL HEATING UNITS FOR THE MONTH............623   DEPARTURE.........+23
TOTAL HEATING UNITS FOR THE SEASON..........4745   DEPARTURE........-421
TOTAL HEATING UNITS LAST SEASON TO DATE.....4555   DIFFERENCE.......+190

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................32 WNW AT 2:21 P.M. 
                   AERO........................32 WNW AT 3:08 P.M.
                   ASOS........................33 NW  AT 3:11 P.M.
                   DAVIS.......................34 M   AT 3:11 P.M ** RMY 34
FASTEST MILE FOR YESTERDAY.....................24 WNW AT 3:08 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................23 NW  AT 3:12 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE.................24 M   AT 3:11 P.M.**
AVERAGE WIND SPEED AND DIRECTION.............13.6 WNW
                   ASOS......................13.0  
                   DAVIS.....................12.2 ** 
** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.19
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........7.97  DEPARTURE......+4.82
                         ASOS..............8.68  
TOTAL PRECIPITATION FOR THE YEAR..........18.08  DEPARTURE......+6.51
                         ASOS.............19.53

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE........-0.4
TOTAL SNOWFALL FOR THE MONTH...............40.1  DEPARTURE.......+31.1
TOTAL SNOWFALL FOR THE SEASON..............84.8  DEPARTURE.......+28.7

PRELIMINARY CLIMATE SUMMARY FOR MARCH 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

3/01 61/37/49/+18/0.00/0.0/378/56    39 ENE AERO 37 ENE RMY N/A 
3/02 40/32/36/+5/3.47/0.7/000/00     73 NNE AERO 70 NNE RMY N/A
3/03 40/32/26/+4/T/T/034/05          52 NNE AERO 50 NNE RMY 49
3/04 39//34/37/+5/T/T/000/00         36 NNE AERO 32 NNE RMY 32 
3/05 40/29/35/+3/.../1.2/261/38      40 NE  AERO 39 NE  RMY 40
3/06 34/29/32/0/0.00/0.0/062/09      20 N   AERO 16 N   RMY N/A
3/07 35/31/33/0/..../.../000/00      52 ENE AERO 53 ENE RMY 50 
3/08 34/28/31/-2/..../.../000/00     44 NNE AERO 47 NNE RMY N/A
3/09 36/24/30/-3/T/T/265/38          28 W   AERO 26 W   RMY N/A 
3/10 37/28/33/0/0.00/0.0/343/49      38 WNW AERO 38 WNW RMY 41
3/11 42/26/34/0/0.00/0.0/.../..      28 NW  AERO 26 NW  RMY 29
3/12 39/26/33/-1/T/T/.../..          36 ENE AERO 33 ENE RMY N/A
3/13 35/26/31/-3/..../23.0/000/00    60 N   AERO 60 N   RMY 64
3/14 36/24/30/-5/..../.../470/66     38 WSW AERO 38 WSW RMY 41
3/15 40/29/35/0/..../.../422/59      44 W   AERO 44 W   RMY 44
3/16 35/23/29/-6/0.00/0.0/308/43     41 NW  AERO 41 NW  RMY 45
3/17 40/15/28/-8/0.00/0.0/.../...    46 W   AERO 45 W   RMY 49
3/18 31/10/21/-15/0.00/0.0/.../..    39 NW  AERO 38 NW  RMY 40
3/19 35/13/24/-12/0.00/0.0/.../..    32 WNW AERO 32 WNW RMY 34

3/20 Low temp since midnight is 18F; normal low is now 28F

DAILY RECORDS FOR MARCH 2018

3/02/18: NEW DAILY RECORD MAXIMUM PRECIPITATION OF 3.47 INS.
         PREVIOUS RECORD WAS 2.15 INS. SET IN 1983

3/13/18: NEW DAILY RECORD MAXIMUM SNOWFALL OF 23.0 INS.
         PREVIOUS RECORD WAS 10.0 INS. SET IN 1993

3/13/18: NEW MONTHLY RECORD MAXIMUM DAILY SNOWFALL OF 23.0 INS.
         PREVIOUS RECORD WAS 18.0 INS. SET ON 8 MARCH 2013

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

RECORDS FOR MARCH 20
HIGH 79 IN 1945
LOW 4 IN 1885
PRECIP 1.39 INS. IN 1957
SNOWFALL 11.4 INS. IN 1957
PEAK GUST 63 MPH SE IN 1975

RECORDS FOR MARCH 21
HIGH 81 IN 1921
LOW 2 IN 1885
PRECIP 2.67 INS. IN 1974
SNOWFALL 10.6 INS. IN 1958
PEAK GUST 72 MPH NE IN 1958

TODAY'S REPORT PREPARED BY: Benjamin Turner and Kaitlin A. Geagan