Thursday, April 28, 2016

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, APRIL 28, 2016
ALL TIMES ARE IN EASTERN STANDARD TIME

COOL VERY DRY WEATHER CONTINUES

Cooler than normal and very dry air continues today with dew points
dropping to the teens.  The relative humidity is in the 20% range
again today like yesterday.

Today’s Observations:

7 A.M.
Weather: Thin scattered cirrus, cirrus SE-W
Temperature: 43F; Dew Point: 15F; Wind: NNW at 7 kts,
Wind: Direction variable WNW-N
Sea-level pressure: 30.06 ins. Hg, rising steadily
Visibility: 70 miles
6-hr Max temp: 43F
6-hr Min temp: 37F
24-hr precip: 0.00 in.
BHO SA 1155 250 -SCT 70 179/43/15/3307/006/ CI SE-W WND 29V01/
8/001 52024 10043 20037

10 A.M.
Weather: Scattered cirrus [two levels), clear sky NW-NE
Temperature: 50F; Dew Point: 18F; Wind: NNE at 5 kts,
Wind: Light and variable
Sea-level pressure: 30.06 ins. Hg, rising, then falling slightly
but still higher than 3 hours ago
Visibility: 75 miles
BHO SA 1455 220 SCT 250 -SCT 75 181/50/18/0205/006/ CLR SKY NW-NE
WND L/V/ 8/001 50002

1 P.M.
Weather: Scattered altocumulus lenticularis, scattered cirrocumulus
lenticularis, thin broken cirrus
Temperature: 55F; Dew Point: 19F; Wind: estimated WSW at 4 kts,
Sea-level Pressure: 30.04 ins. HG, falling, then more quickly
Visibility: 75 miles
6-hr Max temp: 56F
6-hr Min temp: 43F
BHO SA 1755 150 SCT 220 SCT 250 -BKN 300 -BKN 75 173/55/19/E2404/004/
PTCHS ACSL/CCSL PTCH CC S/ WND L/V/ 8/049 58008 10056 20043

SUMMARY FOR WEDNESDAY, APRIL 27, 2016

TEMPERATURE (DEGREES F)
MAX…..61   NORMAL…..60
MIN…..33   NORMAL…..42
MEAN….47   NORMAL…..51

DEPARTURE FROM 30-YEAR NORMAL…………………….-4
TOTAL DEPARTURE FOR THE MONTH……………………-12 [-0.6] DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..18   DEPARTURE……….+4
TOTAL HEATING UNITS FOR THE MONTH………….525   DEPARTURE………+14
TOTAL HEATING UNITS FOR THE SEASON………..4944   DEPARTURE…….-1051
TOTAL HEATING UNITS LAST SEASON TO DATE……6230   DIFFERENCE……-1286

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….28  S   AT   6:08 P.M. *
ASOS……………………29  S   AT   5:09 P.M.
DAVIS…………………..27  S   AT   4:17 P.M.  RMY 29
FASTEST MILE FOR YESTERDAY…………………22  S   AT   6:10 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………22  S   AT   6:10 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..21  S   AT   6:10 P.M.
AVERAGE WIND SPEED AND DIRECTION……………10.2 S
ASOS……………………10.3
DAVIS……………………9.2 WSW [240 Deg.] * last of several occurrences

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……….4.17  DEPARTURE……+0.03
ASOS…………..4.36
TOTAL PRECIPITATION FOR THE YEAR……….16.75  DEPARTURE……-1.39
ASOS………….17.37

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……..0.0
TOTAL SNOWFALL FOR THE MONTH……………15.0  DEPARTURE……+12.1
TOTAL SNOWFALL FOR THE SEASON…………..57.5  DEPARTURE…….-5.6

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/+19/0.06/0.0/092/12          39 SSW AERO N/A    RMY 43
4/2  54/40/47/+6/0.47/0.0/023/03           23 SSW AERO N/A    RMY N/A
4/3  40/23/32/-10/0.85/7.7/354/46          46 W   AERO N/A    RMY 55
4/4  28/21/25/-17/0.63/7.3/000/00          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/-12/0.00/0.0/483/62          44 S   AERO N/A    RMY N/A
4/7  56/41/49/+6/1.41/0.0/000/00           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/-7/0.00/0.0/735/93           30 NW  AERO 32 NW  RMY 31
4/11 58/40/49/+4/0.01/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/-1/0.00/0.0/783/97           36 NNE AERO 31 NNE RMY 34
4/17 62/36/49/+2/0.00/0.0/809/100          20 NNE AERO 20 NNE RMY 19
4/18 67/45/56/+8/…/0.0/715/88            28 ENE AERO 29 NE  RMY 28
4/19 55/41/48/0/…/0.0/440/54             25 NW  AERO 30 NW  RMY N/A
4/20 57/41/49/0/0.00/0.0/801/98            29 NNW AERO 30 NNW RMY 29
4/21 76/38/57/+8/0.00/0.0/795/97           28 W   AERO 29 WSW RMY 28
4/22 80/56/68/+19/…./…/..              36 S   AERO 37 S   RMY 36
4/23 60/46/53/+3/…./…/…/..           26 NNW AERO 60 NNW RMY 24
4/24 59/38/49/-1/0.00/0.0/…/..           23 NW  AERO 25 NW  RMY 24
4/25 63/41/52/+2/0.00/0.0/…/..           23 W   AERO 24 W   RMY N/A
4/26 52/35/44/-7/0.36/0.0/…/..           33 E   AERO 35 E   RMY 31
4/27 61/33/47/-4/…./0.0/…/..           28 S   AERO 39 s   RMY 29

4/28 low temp since midnight is 37F; normal now 42F

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

4/22/16: NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 56F,
BREAKS PREVIOUS RECORD OF 55F IN 1977 AND 1992

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

RECORDS FOR APRIL 28
HIGH 92 IN 1990, 2009
LOW 26 IN 1947
PRECIP 2.41 IN 1904
SNOWFALL 10.0 IN. IN 1987
PEAK GUST 69 MPH NE 1967

RECORDS FOR APRIL 29
HIGH 85 IN 1974
LOW 26 IN 1909
PRECIP 1.65 IN 1923
SNOWFALL 1.0 IN. IN 1987
PEAK GUST 55 MPH WNW IN 2010

TODAY’S REPORT PREPARED BY: Robert Skilling