Monday, May 28, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, MAY 28, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

SKIES REMAINED OVERCAST AND TEMPERATURES REMAINED BELOW
SEASONABLE ON THIS MEMORIAL DAY…

Today temperatures continued to be below seasonable with a
max of 61F yesterday, which occurred at midnight. The day
time max was 53F, which is 16 degrees below the daily normal
of 69F. So far today we have a max of 55F, which is 15 degrees
below the normal of 70F.
Skies continue to be overcast today. Showers began yesterday
afternoon and we measured 0.08 inches by 7:00 A.M. today. Since
7:00 A.M. precipitation was very light and ended before 1:00 P.M.
So far we measured a trace of additional rainfall since 7:00 A.M.
Wind, mostly from the NE, remained light and kept temperatures
below seasonable.

Although temperatures have been below seasonable the past two days
May 2018 is still on pace to be one of the warmest May’s on record
at Blue Hill with a mean of 61.3F through the 27th.

Blue Hill Observatory Warmest May Mean Temperature (°F), 1885-2017

1. 61.5 in 2015
2. 61.4 in 1991
3. 61.0 in 1944
4. 60.9 in 2010
5. 59.4 in 1911
59.4 in 1959
7. 59.3 in 1964
59.3 in 2012

Today’s Observations:

7 A.M.
Weather: Light drizzle and fog, overcast nimbostratus
Temperature: 50F; Dew Point: 50F; Wind: NE at 6 kts,
Wind: Light
Sea-level pressure: 30.11 ins. Hg, rising then falling
Visibility: 1/2 mile
6-hr Max temp: 50F
6-hr Min temp: 48F
24-hr Precip: 0.06 ins.
BHO SA 1155 E5 OVC 1/2L-F 197/50/50/0406/011/ PCPN VRY LGT
WND LGT/ 8/02/ 58002 MANUAL 70008 ASOS 70006 10050 20048

10 A.M.
Weather: Light drizzle and fog, overcast nimbostratus
Temperature: 52F; Dew Point: 52F; Wind: NE at 7 kts
Sea-level pressure: 30.11 ins. Hg, rising, then more slowly
Visibility: 2 miles, except NNW-ENE 3/4 of a mile
3-hr Precip: Trace
BHO SA 1455 E9 OVC 2L-F 198/52/52/0507/011/ VSBY 3/4 NNW-ENE
PCPN VRY LGT/ 8/02/ 51001 MANUAL 600//

1 P.M.
Weather: Overcast Stratus
Temperature: 55F; Dew Point: 52F; Wind: NE at 3 kts,
Wind: Light
Sea-level pressure: 30.10 ins. Hg, steady then falling
Visibility: 15 miles, except ENE-E 5 miles and WNW-ENE 10
miles, distant fog in all directions
6-hr Max temp: 55F
6-hr Min temp: 50F
6-hr precip:  Trace
BHO SA 1755 E9 OVC 15 194/55/52/0503/010/ VSBY ENE-E 5
WNW-ENE 10 DSNT FG ALQDS WND LGT/ 8/6// 58004 MANUAL
600// 10055 10050

SUMMARY FOR SUNDAY, MAY 27, 2018

TEMPERATURE (DEGREES F)
MAX…..61   NORMAL…..69
MIN…..47   NORMAL…..51
MEAN….54   NORMAL…..60

DEPARTURE FROM 30-YEAR NORMAL…………………….-6
TOTAL DEPARTURE FOR THE MONTH…………………..+137 [+4.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….11   DEPARTURE………..+5
TOTAL HEATING UNITS FOR THE MONTH…………143   DEPARTURE………-103
TOTAL HEATING UNITS FOR THE SEASON……….5836   DEPARTURE………-445
TOTAL HEATING UNITS LAST SEASON TO DATE…..5627   DIFFERENCE……..+209

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0   DEPARTURE……….-1
TOTAL COOLING UNITS FOR THE MONTH…………..52   DEPARTURE………+35
TOTAL COOLING UNITS FOR THE SEASON………….52   DEPARTURE………+33
TOTAL COOLING UNITS LAST SEASON TO DATE……..56   DEPARTURE……….-4

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..32 ENE AT 12:47 A.M.
AERO…………………….30 ENE AT 12:47 A.M.
ASOS…………………….35 ENE AT 12:48 A.M.
DAVIS……………………31 M   AT 10:12 A.M.** RMY 39
FASTEST MILE FOR YESTERDAY………………….24 ENE AT 12:47 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….24 ENE AT 12:48 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………23 M   AT 12:47 A.M.**
AVERAGE WIND SPEED AND DIRECTION…………..14.9 ENE
ASOS…………………..15.0
DAVIS………………….13.5 M
** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.08  DEPARTURE……-0.07
ASOS…………..0.06
TOTAL PRECIPITATION FOR THE MONTH……….2.00  DEPARTURE……-1.51
ASOS…………..1.95
TOTAL PRECIPITATION FOR THE YEAR……….27.31  DEPARTURE……+5.43
ASOS………….28.87

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

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

5/01 65/39/52/-1/0.00/0.0/625/74    25 WNW AERO 21 WNW RMY 25
5/02 88/59/74/+21/0.00/0.0/584/69   37 WSW AERO 29 WSW RMY 35
5/03 90/67/79/+26/0.13/0.0/433/51   36 SW  AERO 32 WSW RMY 36
5/04 84/67/74/+20/0.05/0.0/102/12   39 SSW AERO 37 SSW RMY N/A
5/05 73/54/64/+10/0.00/0.0/615/72   56 W   AERO 55 W   RMY N/A
5/06 65/48/57/+3/0.21/0.0/000/00    24 NE  AERO 18 NE  RMY 21
5/07 62/49/56/+1/0.00/0.0/713/83    26 ENE AERO 22 NE  RMY 24
5/08 73/46/60/+5/0.00/0.0/852/99    25 SSE AERO 21 ESE RMY 23
5/09 74/48/61/+6/0.00/0.0/768/89    23 ESE AERO 18 ESE RMY 21
5/10 73/48/61/+6/0.03/0.0/355/41    33 S   AERO 30 S   RMY 32
5/11 70/51/61/+5/0.00/0.0/703/81    26 WNW AERO 24 NW  RMY 28
5/12 51/47/49/-7/0.19/0.0/000/00    25 E   AERO 23 E   RMY N/A
5/13 58/46/52/-4/T/0.0/392/45       20 S   AERO 17 S   RMY 16
5/14 73/47/60/+3/T/0.0/557/63       23 S   AERO 18 S   RMY 21
5/15 83/54/69/+12/0.74/0.0/333/38   51 NW  AERO 50 NW  RMY 54 TSTM
5/16 56/49/53/-4/T/0.0/…/..       32 ENE AERO 28 ENE RMY 30
5/17 72/51/62/+5/0.02/0.0/…/..    17 SW  AERO 14 SW  RMY N/A
5/18 62/43/53/-5/0.00/0.0/…/..    35 ENE AERO 33 ENE RMY N/A
5/19 57/43/50/-8/…/0.0/…/..     22 E   AERO 17 E   RMY N/A
5/20 77/54/66/+8/…/0.0/…/..     33 SW  AERO 31 SW  RMY 33 TSTM
5/21 75/52/64/+5/0.00/0.0/…/..    22 W   AERO 18 W   RMY 20
5/22 68/51/60/+1/0.04/0.0/…/..    23 SSW AERO 21 S   RMY 22
5/23 82/51/67/+8/0.06/0.0/…/..    33 NNW AERO 33 NNW RMY 34 TSTM
5/24 74/50/62/+3/0.00/0.0/…/..    28 SSW AERO 25 SSW RMY 27
5/25 86/50/68/+8/0.00/0.0/…/..    40 W   AERO 39 W   RMY 43
5/26 88/61/75/+15/…./0.0/…/..   38 ENE AERO 38 ENE RMY 39
5/27 61/47/54/-6/…./0.0/…/..    32 ENE AERO 30 ENE RMY N/A

5/28 Low temp since midnight is 48F; normal low is now 51F

DAILY RECORDS FOR MAY 2018

5/03/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
BREAKS PREVIOUS RECORD OF 66F SET IN 2001

5/04/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
BREAKS PREVIOUS RECORD OF 66F SET IN 2001

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

RECORDS FOR MAY 28
HIGH 92F IN 2016
LOW 39F IN 1917
PRECIP 2.48 INS 1906
PEAK GUST 51e MPH NE IN 1946

RECORDS FOR MAY 29
HIGH 93F IN 1919
LOW 35F IN 1902
PRECIP 1.63 INS 1990
PEAK GUST 55e MPH NNW IN 1943, WNW IN 1945

TODAY’S REPORT PREPARED BY: Kaitlin Ann Geagan