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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, APRIL 25, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

A FAIR WEATHER DAY WITH LIGHT WINDS ATOP 
GREAT BLUE HILL....

Visibility today was excellent in comparison to the 
beginning of the week, with an average visibility 
of 80 miles. Scattered cumulus and cirrus clouds did
not have any obstruction to incoming sunlight. Wind
remained light throughout the day, with a shift from 
NW-E being observed shortly following the 1 P.M. 
observation. The high so far today is 61F, a degree 
above the daily normal of 60F. The low since midnight 
is 39F, 2 degrees below the normal minimum of 41F.   

The calendar day rainfall on Monday, 4/22, was more than
two and a half inches, which made it one of the wettest 
calendar days ever observed in April. The finalized 
amount for the day will be reported when available. 

BHO Greatest April Calendar Day Precipitation, inches (1885-2019):

1) 3.47 on April 1, 2004
2) 3.18 on April 21, 1991
3) 2.63 on April 16, 2018
4) 2.51 on April 24, 1898
   2.51 on April 13, 2004
6) 2.45 on April 16, 1929
7) 2.41 on April 28, 1904
8) 2.40 on April 10, 1935

Today's Observations:

7 A.M.
Weather: Scattered altocumulus, scattered cirrus
Temperature: 46F; Dew Point: 37F; Wind: NW at 7G13 kts
Sea-level pressure: 29.96 ins. Hg, steady
Visibility: 75 mile
6-hr Max temp: 46F
6-hr Min temp: 39F
24-hr Precip: 0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins. 
BHO SA 1155 130 SCT 300 SCT 75 146/46/37/3207G13/996/ 
8/062 53021 10046 20039 

10 A.M.
Weather: Scattered altocumulus, scattered cirrus
Temperature: 49F; Dew Point: 38F; Wind: NNW at 3 kts,
Wind: Light 
Sea-level pressure: 29.96 ins. Hg, steady
Visibility: 85 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 130 SCT 250 SCT 85 146/49/38/3403/996/ 
WND LGT/ 8/062 50000  

1 P.M.
Weather: Few distant cumulus in all directions, 
scattered cirrus
Temperature: 59F; Dew Point: 36F; Wind: E at 4 kts,
Wind: Light
Sea-level pressure: 29.93 ins. Hg, falling steadily
Visibility: 80 miles
6-hr Max temp: 61F
6-hr Min temp: 46F
6-hr Precip: 0.00 ins.
6-hr snowfall: 0.0 ins. 
BHO SA 1755 250 SCT 80 135/59/36/0804/993/ FEW DSNT CU 
ALQDS/ 8/102 58009 10061 20046   

SUMMARY FOR WEDNESDAY, APRIL 24, 2019 

TEMPERATURE (DEGREES F)
MAX.....65   NORMAL.....59
MIN.....44   NORMAL.....41
MEAN....55   NORMAL.....50

DEPARTURE FROM 30-YEAR NORMAL........................+5
TOTAL DEPARTURE FOR THE MONTH.......................+80 [+3.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............10   DEPARTURE.........-5
TOTAL HEATING UNITS FOR THE MONTH.............392   DEPARTURE........-91
TOTAL HEATING UNITS FOR THE SEASON...........5797   DEPARTURE.......-169
TOTAL HEATING UNITS LAST SEASON TO DATE......5628   DIFFERENCE......+169

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................29 WNW AT 12:34 P.M.
                   AERO.........................29 WNW AT  5:42 P.M.
                   ASOS.........................29 W   AT  3:02 P.M. 
                   DAVIS........................30 S   AT  2:25 A.M.  RMY 30
FASTEST MILE FOR YESTERDAY......................23 WNW AT  3:09 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE...................23 W   AT  3:02 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..................24 WSW AT  3:02 P.M.
AVERAGE WIND SPEED AND DIRECTION..............12.6 WNW
                   ASOS.......................12.5
                   DAVIS......................12.8 WSW [244 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE.......-0.13
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........6.43  DEPARTURE.......+2.68
                         ASOS..............6.33
TOTAL PRECIPITATION FOR THE YEAR..........19.47  DEPARTURE.......+1.72
                         ASOS.............19.48

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0  DEPARTURE........-0.1
TOTAL SNOWFALL FOR THE MONTH.............TRACE  DEPARTURE........-2.9
TOTAL SNOWFALL FOR THE SEASON.............47.6  DEPARTURE.......-15.0


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

04/01 45/29/37/-4/0.00/0.0/726/98           40 WNW AERO 37 W   RMY 42
04/02 50/27/39/-2/..../0.0/582/79           29 S   AERO 25 S   RMY 31
04/03 62/35/49/+7/..../0.0/468/63           54 W   AERO 58 W   RMY 56
04/04 50/34/42/0/..../0.0/690/93            46 W   AERO 41 W   RMY N/A
04/05 47/27/37/-6/..../0.0/324/44           23 SSW AERO 17 SSW RMY 23
04/06 64/32/48/+5/..../0.0/516/69           24 NW  AERO 18 W   RMY 26
04/07 66/41/54/+11/0.00/0.0/306/41          24 S   AERO 18 S   RMY 25
04/08 48/34/41/-3/0.49/0.0/.../..           25 NE  AERO 20 NE  RMY 26
04/09 40/32/36/-8/0.08/0.0/.../..           23 NE  AERO 16 N   RMY 25
04/10 43/30/37/-8/T/T/T/..                  32 NW  AERO 26 NW  RMY 36
04/11 51/29/40/-5/0.00/0.0/.../..           23 NW  AERO 18 NW  RMY N/A
04/12 53/38/46/+1/..../0.0/.../..           35 SSW AERO 29 SSW RMY 39
04/13 71/54/63/+17/..../0.0/.../..          38 SSW AERO 32 SSW RMY N/A
04/14 71/51/61/+15/..../0.0/.../..          25 S   AERO 18 S   RMY N/A
04/15 67/40/54/+7/..../0.0/.../..           46 W   AERO 52 W   RMY 50
04/16 58/37/48/+1/0.00/0.0/.../..           46 W   AERO 44 W   RMY 44 
04/17 62/36/49/+2/0.00/0.0/.../..           26 ESE AERO 25 S   RMY 28
04/18 63/39/51/+3/0.00/0.0/.../..           44 S   AERO 44 S   RMY 50
04/19 71/58/65/+17/.../0.0/.../..           47 SSW AERO 51 SSW RMY 52
04/20 68/60/64/+15/.../0.0/.../..           50 SSW AERO 54 SSW RMY 52
04/21 68/51/60/+11/.../0.0/.../..           35 S   AERO 35 S   RMY N/A
04/22 53/45/49/0/.../0.0/.../..             35 NNE AERO 32 NNE RMY 35
04/23 52/44/48/-2/.../0.0/.../..            30 NNE AERO 26 NNE RMY N/A
04/24 65/44/55/+5/.../0.0/.../..            29 WNW AERO 29 WNW RMY 30

04/25 Low temp since midnight is 39F; normal low is 41F


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

RECORDS FOR APRIL 25
HIGH 83 IN 2009
LOW 24 IN 1892
PRECIP 1.38 IN. IN 1901
SNOWFALL 0.7 IN. IN 2002
PEAK GUST 66 MPH SE IN 1968

RECORDS FOR APRIL 26
HIGH 88 IN 2009
LOW 23 IN 1919
PRECIP 1.64 IN. IN 1931
SNOWFALL 1.0 IN. IN 2000
PEAK GUST 53 MPH SSW IN 1996

TODAY'S REPORT PREPARED BY: Benjamin Turner