Saturday, May 30, 2020

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, MAY 30, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

CLOUDY WITH SOME RAIN IN THE EARLY MORNING
HOURS, CLEARING UP IN THE AFTERNOON….

We observed a decrease in clouds and an increase
in visibility as the day went on, despite a very
slow decrease in pressure. Some rain early in the
morning left 0.12 inches in the gauge, measured at
the 7 A.M. observation. Fog this morning dissipated
rather quickly, with visibility increasing from 10
miles to 70 miles by 1 P.M. This was in conjunction
with a decrease in humidity from 97% this morning
to 38% in the afternoon.

The high so far today is 77F, this is 7 degrees
above the daily normal high of 70F. The low since
midnight is 64F, which is 12 degrees above the daily
normal low of 52F.

Today’s Observations:

7 A.M.
Weather: Broken stratocumulus
Temperature: 66F; Dew Point: 65F; Relative Humidity: 97%
Wind: SW at 8 kts
Sea-level pressure: 29.84 ins. Hg: rising steadily
Visibility: 10 miles, thin fog
6-hr Max temp: 66F
6-hr Min temp: 64F
24-hr Precip:  0.12 ins.
24-hr Snowfall: 0.0 ins.
BHO SA 1155 E40 BKN 10 105/66/65/2308/984/ THN FG ALQDS/
8/800 53006 10066 20064

10 A.M.
Weather: Broken stratocumulus and cirrus
Temperature: 74F; Dew Point: 59F; Relative Humidity: 83%
Wind: W at 14 kts
Sea-level pressure: 29.84 ins. Hg: steady
Visibility: 60 miles
3-hr Precip:  0.00 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1455 E40 BKN 250 BKN 60 105/74/59/2714/984/ 8/802 52000

1 P.M.
Weather: Scattered cumulus, broken altocumulus and cirrus
Temperature: 76F; Dew Point: 54F; Relative Humidity: 47%
Wind: W at 12G20 kts
Sea-level pressure: 29.82 ins. Hg: falling steadily
Visibility: 70 miles
6-hr Max temp: 77F
6-hr Min temp: 68F
6-hr Precip:  0.00 ins.
6-hr Snowfall: 0.0 ins.
BHO SA 1755 45 SCT 110 SCT 250 BKN 70 099/76/54/2712G20/982/
8/182 58006 10077 20066

SUMMARY FOR FRIDAY, MAY 29, 2020

TEMPERATURE (DEGREES F)
MAX…..78   NORMAL…..70
MIN…..66   NORMAL…..52
MEAN….72   NORMAL…..61

DEPARTURE FROM 30-YEAR NORMAL……………..+11
TOTAL DEPARTURE FOR THE MONTH……………..-20 [-0.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………… 0  DEPARTURE……..-6
TOTAL HEATING UNITS FOR THE MONTH…………..282  DEPARTURE…….+24
TOTAL HEATING UNITS FOR THE SEASON…………5803  DEPARTURE……-489
TOTAL HEATING UNITS LAST SEASON TO DATE…….6206  DEPARTURE……-403

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………….7  DEPARTURE……..+6
TOTAL COOLING UNITS FOR THE MONTH……………26  DEPARTURE……..+7
TOTAL COOLING UNITS FOR THE SEASON…………..26  DEPARTURE……..+5
TOTAL COOLING UNITS LAST SEASON TO DATE……….8  DEPARTURE……..18

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..41 SSW AT  8:34 P.M.
AERO…………………….41 SSW AT  8:20 P.M.
ASOS…………………….42 SSW AT  9:39 P.M.
DAVIS……………………42 S   AT  9:09 P.M. RMY 43
FASTEST MILE FOR YESTERDAY………………….29 SSW AT  9:09 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….29 SSW AT  9:07 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………29 SSW AT  8:46 P.M.
AVERAGE WIND SPEED AND DIRECTION…………….18.3 SSW
ASOS…………………….18.4
DAVIS……………………17.1 SSW [208 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.12  DEPARTURE……-0.02
ASOS…………..0.12
TOTAL PRECIPITATION FOR THE MONTH……….2.75  DEPARTURE……-1.05
ASOS…………..2.71
TOTAL PRECIPITATION FOR THE YEAR……….19.79  DEPARTURE……-2.56
ASOS………….20.31

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……..0.0
TOTAL SNOWFALL FOR THE MONTH…………..Trace  DEPARTURE……..0.0
TOTAL SNOWFALL FOR THE SEASON…………..31.9  DEPARTURE……-30.8

PRELIMINARY CLIMATE SUMMARY FOR MAY 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

05/01  64/52/58/+5/…./0.0/000/00         46 SSE  AERO 44 SSE RMY N/A
05/02  70/42/56/+3/…./0.0/729/86         41 NW   AERO 40 NW  RMY N/A
05/03  78/55/67/+14/0.00/0.0/613/72        35 SSW  AERO 35 SSW RMY 36
05/04  72/45/59/+5/T/0.0/247/29            37 NW   AERO 40 WNW RMY 39
05/05  60/40/50/-4/0.00/0.0/821/96         31 NW   AERO 32 NW  RMY N/A
05/06  57/38/48/-6/T/0.0/498/58            24 ESE  AERO 22 ENE RMY 22
05/07  63/37/50/-5/0.00/0.0/576/67         30 WSW  AERO 29 WSW RMY N/A
05/08  57/40/49/-6/…./0.0/328/38         31 W    AERO 32 W   RMY N/A
05/09  44/32/38/-17/…./T/484/56          52 W    AERO 53 W   RMY 54
05/10  59/31/45/-10/0.00/0.0/763/88        46 W    AERO 46 W   RMY 49
05/11  65/43/54/-2/0.22/0.0/322/37         39 S    AERO 43 S   RMY 41
05/12  55/37/46/-10/0.00/0.0/801/92        37 W    AERO 37 W   RMY 37
05/13  59/32/46/-10/0.00/0.0/864/99        37 WNW  AERO 37 WNW RMY 38
05/14  70/40/55/-2/0.00/0.0/831/95         29 W    AERO 26 W   RMY 27
05/15  78/50/64/+7/…./0.0/535/61         40 WSW  AERO 40 WSW RMY 43
05/16  69/47/58/+1/…./0.0/730/83         31 NW   AERO 31 NW  RMY 32
05/17  67/47/57/0/0.00/0.0/132/15          22 SSW  AERO N/A    RMY 21
05/18  60/47/54/-4/T/0.0/…/..            24 W    AERO 22 ENE RMY N/A
05/19  56/45/51/-7/0.00/0.0/…/..         35 ENE  AERO 34 ENE RMY 32
05/20  63/43/53/-5/0.00/0.0/…/..         22 ESE  AERO 20 SE  RMY 19
05/21  76/42/59/0/0.00/0.0/…/..          26 S    AERO 25 S   RMY 25
05/22  82/50/66/+7/0.00/0.0/…/..         29 W    AERO 29 W   RMY 28
05/23  67/44/56/-3/0.02/0.0/…/..         42 ENE  AERO 43 ENE RMY 40
05/24  58/43/51/-8/T/0.0/…/..            27 ENE  AERO 24 ENE RMY N/A
05/25  66/46/56/-4/0.00/0.0/…/..         18 ENE  AERO 18 ENE RMY N/A
05/26  82/56/69/+9/0.00/0.0/…/..         21 S    AERO 21 S   RMY 21
05/27  84/59/72/+12/0.00/0.0/…/..        31 SSW  AERO 31 SSW RMY 31
05/28  77/63/70/+9/…/0.0/…/..          33 SSW  AERO 33 S   RMY 33
05/29  78/66/72/+11/…./…/…/..        41 SSW  AERO 41 SSW RMY 43

05/30 The low since midnight is 64F, the daily normal low is 52F

DAILY RECORDS FOR MAY 2020

5/13/2020: NEW RECORD LOW OF 32F, REPLACING 35F SET IN
1914 AND 2005

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

RECORDS FOR MAY 30
HIGH 93F IN 1929
LOW 39F IN 1949,1961
PRECIP 1.47 INS 1948
PEAK GUST 61e MPH NW IN 1945

RECORDS FOR MAY 31
HIGH 92F IN 1944,1987,2013
LOW 35F IN 1961
PRECIP 5.02 INS 1984 (RECORD FOR MAY)
PEAK GUST 54e MPH WNW IN 1945

TODAY’S REPORT PREPARED BY: Benjamin Turner