Friday, May 25, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, MAY 25, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

WARM, DRY, AND BREEZY SPRING DAY ON TOP OF GREAT
BLUE HILL…

Today we had above seasonable temperatures with a max so far
of 84F. This is already 15 degrees above the daily normal of 69F.
Temperatures rose quickly today and our overnight low was 1
degree above the daily normal of 50F. Humidity remained low
today for a nice dry heat. Although the air was dry we had a
lingering distant haze today limiting visibility to just barely 40 miles
at each observation.The sky remain mostly covered with a layer of
cirrostratus clouds.
The pressure began to drop today just after midnight and has
continued to drop more rapidly throughout the day. This caused the
wind to pick up. The afternoon became very breezy with frequent
gust over 26 kts (30 MPH). The peak gust so far today is already
35 kts (40 MPH).

Today’s Observations:

7 A.M.
Weather: Scattered cirrostratus
Temperature: 61F; Dew Point: 48F; Wind: WSW at 13G24 kts
Sea-level pressure: 29.98 ins. Hg, steady then falling
Visibility: 40 miles, distant haze in all directions
6-hr Max temp: 61F
6-hr Min temp: 50F
24-HR Precip: 0.00 ins.
BHO SA 1155 300 SCT 40 151/61/48/2513G24/998/ DSNT HZ ALQDS/
8/008 58002 10061 20050

10 A.M.
Weather: Broken thin cirrostratus
Temperature: 80F; Dew Point: 52F; Wind: W at 12G22 kts
Sea-level pressure: 29.93 ins. Hg, falling, then more rapidly
Visibility: 40 miles, distant haze in all directions
3-hr Precip: 0.00 ins.
BHO SA 1455 300 -BKN 40 136/80/52/2712G22/993/ DSNT HZ ALQDS/
8/008 58015

1 P.M.
Weather: Scattered altocumulus, broken cirrostratus
Temperature: 84F; Dew Point: 45F; Wind: W at 17G29 kts,
Peak wind: 33 kts (38 MPH) at 12:16 P.M.
Sea-level pressure: 29.85 ins. Hg, falling, then more rapidly
Visibility: 40 miles, distant haze in all directions
6-hr Max temp: 84F
6-hr Min temp: 61F
6-hr precip:  0.00 ins.
BHO SA 1755 200 SCT E300 BKN 40 109/84/45/2717G29/985/
DSNT HZ ALQDS PK WND 2733/16/ 8/048 56027 10084 20061

SUMMARY FOR THURSDAY, MAY 24, 2018

TEMPERATURE (DEGREES F)
MAX…..74   NORMAL…..69
MIN…..50   NORMAL…..50
MEAN….62   NORMAL…..59

DEPARTURE FROM 30-YEAR NORMAL…………………….+3
TOTAL DEPARTURE FOR THE MONTH…………………..+120 [+4.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..3   DEPARTURE……….-4
TOTAL HEATING UNITS FOR THE MONTH…………132   DEPARTURE………-96
TOTAL HEATING UNITS FOR THE SEASON……….5825   DEPARTURE……..-438
TOTAL HEATING UNITS LAST SEASON TO DATE…..5593   DIFFERENCE…….+232

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0   DEPARTURE……….-1
TOTAL COOLING UNITS FOR THE MONTH…………..39   DEPARTURE………+26
TOTAL COOLING UNITS FOR THE SEASON………….39   DEPARTURE………+24
TOTAL COOLING UNITS LAST SEASON TO DATE……..56   DEPARTURE………-17

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….28 SSW AT 7:17 P.M.
AERO……………………35 SSW AT 7:17 P.M.
ASOS……………………28 SSW AT 7:21 P.M.
DAVIS…………………..27 M   AT 7:16 P.M.** RMY 27
FASTEST MILE FOR YESTERDAY…………………21 SSW AT 7:17 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………22 S  AT 7:17 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..21 M   AT 7:17 P.M.**
AVERAGE WIND SPEED AND DIRECTION…………..9.3 SSW
ASOS…………………..8.9
DAVIS………………….9.2 M**
** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.15
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.88  DEPARTURE……-1.17
ASOS…………..1.85
TOTAL PRECIPITATION FOR THE YEAR……….27.19  DEPARTURE……+5.77
ASOS………….28.77

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 77/52/65/+6/0.00/0.0/…/..    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 Low temp since midnight is 50F; 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 25
HIGH 91F IN 2007
LOW 37F IN 1967
PRECIP 3.73 INS IN 1967
PEAK GUST 83 MPH NE IN 1967 (RECORD FOR MAY)

RECORDS FOR MAY 26
HIGH 94F IN 2010
LOW 37F IN 1972,2013
PRECIP 1.73 INS IN 2003
SNOWFALL TRACE IN 1967 (Fell as ice pellets in nor’easter)
PEAK GUST 62 MPH NE IN 1967

TODAY’S REPORT PREPARED BY: Kaitlin Geagan