Sunday, April 29, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, APRIL 29, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

LIGHT DRIZZLE ENDS, AND OVERCAST SKIES OPEN UP IN THE EARLY
AFTERNOON….

We observed a light drizzle this morning, that measured 0.04
inches at 10:00 A.M. Precipitation ended at 11:00 A.M., and
the sun broke through the decreasing clouds around
noontime. This allowed us to reach a max of 58F by 1 P.M.,
3 degrees under the daily normal of 61F. The low since
midnight was 49F, 6 degrees above the normal of 43F. Wind
was light today, staying at or under 10 mph.

Today’s Observations:

7 A.M.
Weather: Broken altostratus
Temperature: 50F; Dew Point: 46F; Wind: NW at 7G11 kts
Sea-level pressure: 29.84 ins. Hg, rising, then more rapidly
Visibility: 50 miles, except S-NNE 40 miles, distant fog S-NNE
6-hr Max temp: 52F
6-hr Min temp: 49F
24-hr precip:  0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1155 E110 BKN 50 104/50/46/3207G11/984/ VSBY S-NNE 40
DSNT FG S-NNE/ 8/020 53009 10052 20049

10 A.M.
Weather: Overcast nimbostratus, light drizzle
Temperature: 50F; Dew Point: 46F; Wind: N at 1 kt,
Wind: Light and variable
Sea-level pressure: 29.81 ins. Hg, rising, then more slowly
Visibility: 30 miles, except 20 SE-NW, distant fog SE-NW
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins.
BHO SA 1455 E65 OVC 30L- 096/50/46/3601/981/ VSBY SE-NW 20
DSNT FG SE-NW WND L/V/ 8/02/ 50008 MANUAL 60004 ASOS 60004

1 P.M.
Weather: Broken cumulus and stratocumulus, broken altocumulus
Temperature: 58F; Dew Point: 44F; Wind: S at 9G17 kts,
Sea-level pressure: 29.78 ins. Hg, falling, then more slowly
Visibility: 40 miles
6-hr Max temp: 58F
6-hr Min temp: 49F
6-hr precip:   0.04 ins
6-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1755 E60 BKN 110 BKN 40 083/58/44/1909G17/978/ 8/080 56013
MANUAL 60004 ASOS 60004 10058 20049

SUMMARY FOR SATURDAY, APRIL 28, 2018

TEMPERATURE (DEGREES F)
MAX…..73   NORMAL…..61
MIN…..47   NORMAL…..42
MEAN….60   NORMAL…..52

DEPARTURE FROM 30-YEAR NORMAL………………………+8
TOTAL DEPARTURE FOR THE MONTH……………………..-73 [-2.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..5   DEPARTURE……….-8
TOTAL HEATING UNITS FOR THE MONTH…………595   DEPARTURE………+70
TOTAL HEATING UNITS FOR THE SEASON……….5653   DEPARTURE……..-356
TOTAL HEATING UNITS LAST SEASON TO DATE…..5320   DIFFERENCE…….+333

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….25 S AT 7:46 P.M.
AERO……………………21 S AT 7:46 P.M.
ASOS……………………25 S AT 7:46 P.M.
DAVIS…………………..27 M AT 4:47 P.M.** RMY 25
FASTEST MILE FOR YESTERDAY…………………20 S AT 7:28 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………20 S AT 7:27 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..20 M AT 4:48 P.M.**
AVERAGE WIND SPEED AND DIRECTION…………..10.0 SW
ASOS……………………9.9
DAVIS………………….10.0 M **
*  Last of multiple occurrences
** Davis direction malfunctioning

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……….6.09  DEPARTURE……+1.79
ASOS…………..6.28
TOTAL PRECIPITATION FOR THE YEAR……….24.89  DEPARTURE……+6.77
ASOS………….26.52

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……..-0.1
TOTAL SNOWFALL FOR THE MONTH…………….2.6  DEPARTURE……..-0.4
TOTAL SNOWFALL FOR THE SEASON…………..92.8  DEPARTURE…….+30.0

PRELIMINARY CLIMATE SUMMARY FOR APRIL 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
*   : Estimated data

4/01 58/33/46/+5/0.00/0.0/336/44   45 SSW AERO 43 SSW RMY N/A
4/02 38/30/34/-7/0.13/1.6/077/10   20 SSW AERO 15 SSW RMY 17
4/03 48/30/39/-3/…./0.0/238/31   28 SSE AERO 25 SSE RMY 25
4/04 54/36/45/+3/…./0.0/000/00   56 WNW AERO 56 WNW RMY 54
4/05 40/27/34/-9/0.00/0.0/760/98   53 WNW AERO 53 WNW RMY 52
4/06 41/25/33/-10/0.25/1.0/156/20  37 S   AERO 36 S   RMY 38
4/07 46/32/35/-4/0.00/0.0/312/40   32 WNW AERO 35 WNW RMY 34
4/08 41/29/35/-9/0.00/0.0/290/37   35 WNW*AERO 31 WNW RMY 34
4/09 45/24/35/-9/0.00/0.0/715/01   28 WNW*AERO 25 WNW RMY 29
4/10 39/31/35/-10/T/T/000/00       14 SSW AERO 13 SSW RMY N/A
4/11 48/29/39/-6/T/0.0/364/46      24 SSE AERO 23 SSE RMY 25
4/12 61/33/47/+2/0.03/0.0/…/..   39 SSW AERO 38 SSW RMY 41
4/13 65/47/56/+10/T/0.0/…/..     37 SSW AERO 37 SSW RMY N/A
4/14 51/36/44/-2/0.00/0.0/…/..   33 ENE AERO 31 ENE RMY N/A
4/15 36/30/33/-14/…./T/…/..    39 ENE AERO 39 ENE RMY N/A
4/16 55/32/44/-3/…./…/..       41 ENE AERO 43 ENE RMY 41
4/17 48/36/42/-5/0.00/0.0/…/..   37 W   AERO 33 W   RMY 37
4/18 53/32/43/-5/…./0.0/…/..   35 W   AERO 31 W   RMY 34
4/19 41/34/38/-10/0.22/T/…/..    28 WNW AERO 25 WNW RMY N/A
4/20 52/31/42/-7/0.00/0.0/…/..   34 NW  AERO 33 NW  RMY 36
4/21 60/33/47/-2/0.00/0.0/…/..   28 NW  AERO 26 NW  RMY 29
4/22 61/36/49/0/0.00/0.0/…/..    25 NW  AERO 24 NW  RMY 26
4/23 62/40/51/+1/0.00/0.0/…/..   25 S   AERO 25 S   RMY 26
4/24 67/39/53/+3/0.00/0.0/…/..   31 S   AERO 29 S   RMY 32
4/25 57/47/52/+2/…./0.0/…/..   32 SE  AERO 32 SE  RMY 33
4/26 66/48/57/+6/…./0.0/…/..   36 WNW AERO 35 WNW RMY 37
4/27 60/45/53/+2/…./0.0/…/..   18 W   AERO 15 W   RMY N/A
4/28 73/47/60/+8/0.00/0.0/…/..   25 S   AERO 21 S   RMY 25

4/29 Low temp since midnight is 49F; normal low is now 42F

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

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

RECORDS FOR APRIL 30
HIGH 86 IN 1942
LOW 30 IN 1931
PRECIP 1.41 IN 1991
SNOWFALL 0.3 IN. IN 1909
PEAK GUST 64e MPH NW IN 1978

TODAY’S REPORT PREPARED BY: Benjamin Turner