Sunday, April 17, 2016

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, APRIL 17, 2016
ALL TIMES ARE IN EASTERN STANDARD TIME

VERY DRY CONDITIONS WITH A MOSTLY CLEAR SKY TODAY…

Winds have been light and variable after a chilly start.
The cold air has warmed up during the morning and we have
seen relative humidity levels drop down into the 20’s
under sunny skies with only a few high thin cirrus clouds
around.  Temperatures had reached well into the upper 50’s
by the 1 o’clock observation and the air remained very dry.

Today’s Observations:

7 A.M.
Weather: Clear, SKC
Temperature: 44F; Dew Point: 31F; Wind: N at 4 kts,
Wind: Light
Sea-level pressure: 30.46 ins. Hg, rising, then more slowly
Visibility: 70 miles
6-hr Max temp: 44F
6-hr Min temp: 36F
24-hr precip: 0.00 ins.
BHO SA 1155 CLR 70 311/44/31/1004/046/ SKC LGT DSNT HZ WND
LGT/ 8/000 51010 10044 20036

10 A.M.
Weather: Few Thin Cirrostratus W-NE Distant
Temperature: 53F; Dew Point: 23F; Wind: VRB at 4 kts,
Wind: Light and Variable
Sea-level pressure: 30.43 ins. Hg, rising then falling
Visibility: 70 miles
BHO SA 1455 CLR 70 306/53/23/VRB06/043/ FEW THN CS W-NE
DSNT LGT DSNT HZ WND LGT AND VRBL/ 8/005 58005

1 P.M.
Weather: Few Thin Cirrostratus
Temperature: 59F; Dew Point: 24F; Wind: VRB at 06 kts,
Wind: Light and Variable
Sea-level Pressure: 30.37 ins. HG, falling
Visibility: 70 miles,
6-hr Max temp: 59F
6-hr Min temp: 44F
BHO SA 1755 CLR 70 285/59/24/VRB06/037/ FEW THN CS ALQDS
DSNT LGT DSNT HZ WND LGT AND VRBL/ 8/005 58021 10059 20044

SUMMARY FOR SATURDAY, APRIL 16, 2016

TEMPERATURE (DEGREES F)
MAX…..52   NORMAL…..56
MIN…..39   NORMAL…..38
MEAN….46   NORMAL…..47

DEPARTURE FROM 30-YEAR NORMAL…………………….-1
TOTAL DEPARTURE FOR THE MONTH……………………-43 [-3.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..19   DEPARTURE……….+1
TOTAL HEATING UNITS FOR THE MONTH………….379   DEPARTURE………+42
TOTAL HEATING UNITS FOR THE SEASON………..4798   DEPARTURE…….-1022
TOTAL HEATING UNITS LAST SEASON TO DATE……6055   DIFFERENCE……-1257

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….36 NNE AT 11:43 A.M.
ASOS……………………35 NE  AT 11:55 A.M.
DAVIS…………………..32 NNE AT 10:07 A.M. RMY 34
FASTEST MILE FOR YESTERDAY…………………23 NNE AT 11:55 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………23 NE  AT 11:02 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..22 NNE AT 11:55 A.M.
AVERAGE WIND SPEED AND DIRECTION……………13.7 NE
ASOS……………………13.2
DAVIS…………………..10.0 NNE [29 Deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.14
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….3.54  DEPARTURE……+0.89
ASOS…………..3.83
TOTAL PRECIPITATION FOR THE YEAR……….16.12  DEPARTURE……-0.53
ASOS………….16.84

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE…….-0.1
TOTAL SNOWFALL FOR THE MONTH……………15.0  DEPARTURE……+12.7
TOTAL SNOWFALL FOR THE SEASON…………..57.5  DEPARTURE…….-5.0

PRELIMINARY CLIMATE SUMMARY FOR APRIL CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/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

4/1  66/54/60/+19/…./0.0/092/12          39 SSW AERO N/A    RMY 43
4/2  54/40/47/+6/…./0.0/023/03           23 SSW AERO N/A    RMY N/A
4/3  40/23/32/-10/…./7.7/354/46          46 W   AERO N/A    RMY 55
4/4  28/21/25/-17/0.68/7.3/000/00          29 NNE AERO N/A    RMY 25
4/5  35/19/27/-16/0.00/0.0/660/85          25 NW  AERO N/A    RMY 27
4/6  41/21/31/-12/…./0.0/483/62          44 S   AERO N/A    RMY N/A
4/7  56/41/49/+6/…./0.0/000/00           53 SSE AERO 59 SSE RMY 55
4/8  52/32/42/-2/T/0.0/353/45              41 WSW AERO 45 WSW RMY 42
4/9  47/29/38/-6/0.00/0.0/417/53           33 NW  AERO 39 NW  RMY 32
4/10 49/26/38/-7/0.01/0.0/735/93           30 NW  AERO 32 NW  RMY 31
4/11 58/40/49/+4/0.00/T/182/23             47 S   AERO 52 S   RMY N/A
4/12 59/37/48/+3/0.30/0.0/040/05           53 S   AERO 60 S   RMY 54
4/13 53/33/43/-3/0.00/0.0/798/100          21 NNW AERO 25 NNW RMY 21
4/14 48/33/41/-5/0.00/0.0/793/99           28 ENE AERO 28 NNE RMY 26
4/15 54/35/45/-2/0.00/0.0/804/100          26 NNE AERO 28 NNE RMY N/A
4/16 52/39/46/-1/0.00/0.0/…/…          36 NNE AERO 31 NNE RMY 34

4/17  low temp since midnight is 36F; normal now 38F

DAILY RECORDS FOR APRIL 2016

4/1/16: NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 54F,
BREAKS PREVIOUS RECORD OF 51F SET IN 1948

4/4/16: NEW DAILY RECORD SNOWFALL OF 7.3 INS,
BREAKS PREVIOUS RECORD OF 3.7 INS SET IN 1975

4/4/16: NEW DAILY RECORD LOW MAXIMUM TEMPERATURE OF 28F,
BREAKS PREVIOUS RECORD OF 32F SET AND TIED IN 1896, 1908, 1975

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

RECORDS FOR APRIL 17
HIGH 93 IN 2002
LOW 21 IN 1908
PRECIP 1.68 IN 1954
SNOWFALL 1.0 IN. IN 1899
PEAK GUST 63 MPH ESE IN 2011

RECORDS FOR APRIL 18
HIGH 92 IN 1976
LOW 23 1887
PRECIP 1.48 IN 1954
SNOWFALL 3.7 IN. IN 1965
PEAK GUST 59 MPH S IN 1982

TODAY’S REPORT PREPARED BY: Robert Millette