Saturday, June 30, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, JUNE 30, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

HEAT CONTINUES TO BUILD OVER SOUTHERN NEW ENGLAND

The heat which began to build into the region yesterday has intensified
today. After reaching 87F yesterday at the summit, we had already reached
89F by the 2PM EDT observation today. This is the hottest weather of the
month, and we are close to our first 90 degree day since May 3. The record
high for today is 94F, set in 1964. Winds have been very light today, with
the direction variable, providing little relief to the heat. Dew points
running mainly in the low 60s have added a bit of humidity as well.

Skies have been partly cloudy today, with mainly cirrus and altocumulus
clouds observed. This mid and high level cloudiness is largely the result of
dissipating mesoscale convective systems moving out of southern Canada. A
typical summer haze has kept the visibility steady at around 40 miles today.

Today’s Observations:

7 A.M.
Weather: Scattered altocumulus, thin broken cirrus, few altocumulus
lenticularis SW
Temperature: 75F; Dew Point: 64F; Wind: N at 7 kts,
Sea-level pressure: 30.05 ins. Hg, rising, then more slowly
Visibility: 40 miles, distant haze
6-hr Max temp: 75F
6-hr Min temp: 69F
24-hr Precip: 0.00 ins.
BHO SA 1155 100 SCT E250 -BKN 40 176/75/64/3507/005/
FEW ACSL SW DSNT HZ/ 8/051 51014 10075 20069

10 A.M.
Weather: Thin broken cirrus, few small cumulus distant west, few
patches of dense cirrus W-NNE
Temperature: 84F; Dew Point: 63F; Wind: estimated S at 5 kts,
Wind: Light and variable
Sea-level pressure: 30.02 ins. Hg, rising then falling
Visibility: 40 miles, distant haze
3-hr Precip: 0.00 ins.
BHO SA 1455 E250 –BKN 40 167/84/63/E1805/002/ FEW SML CU DSNT W
FEW PTCHS DNS CI W-NNE DSNT HZ WND L/V/ 8/101 58009

1 P.M.
Weather: Scattered altocumulus, thin broken cirrus, few cumulus distant
ESE-S and distant SW-NW
Temperature: 88F; Dew Point: 60F; Wind: estimated SW at 5 kts,
Wind: Light and variable
Sea-level pressure: 30.03 ins. Hg, rising slightly
Visibility: 40 miles, distant haze
6-hr Max temp: 89F
6-hr Min temp: 75F
6-hr precip: 0.00 ins.
BHO SA 1755 150 SCT E250 -BKN 40 171/88/60/E2305/003/
FEW CU DSNT ESE-S AND DSNT SW-NW DSNT HZ WND L/V/
8/151 50004 10089 20075

SUMMARY FOR FRIDAY, JUNE 29, 2018

TEMPERATURE (DEGREES F)
MAX…..87   NORMAL…..79
MIN…..66   NORMAL…..61
MEAN….77   NORMAL…..70

DEPARTURE FROM 30-YEAR NORMAL…………………….+7
TOTAL DEPARTURE FOR THE MONTH……………………-16 [-0.7 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..0   DEPARTURE………..-1
TOTAL HEATING UNITS FOR THE MONTH………….69   DEPARTURE………..-4
TOTAL HEATING UNITS FOR THE SEASON……….5916   DEPARTURE………-459
TOTAL HEATING UNITS LAST SEASON TO DATE…..5725   DIFFERENCE……..+191

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..12   DEPARTURE……….+6
TOTAL COOLING UNITS FOR THE MONTH…………..82   DEPARTURE………-17
TOTAL COOLING UNITS FOR THE SEASON…………144   DEPARTURE………+21
TOTAL COOLING UNITS LAST SEASON TO DATE…….192   DEPARTURE………-48

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..18 W   AT  5:32 P.M.*
AERO…………………….16 W   AT  5:18 P.M.
ASOS…………………….18 W   AT  5:04 P.M.
DAVIS……………………19 M   AT  9:30 P.M.** RMY 18
FASTEST MILE FOR YESTERDAY………………….13 WNW AT  9:54 P.M.*
MAXIMUM 2-MINUTE ASOS AVERAGE……………….14 W   AT  9:49 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………12 M   AT 10:53 P.M.**
AVERAGE WIND SPEED AND DIRECTION……………8.2 W
ASOS……………………8.6
DAVIS…………………..7.3
*Last of several occurrences
**Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.12
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….2.85  DEPARTURE……-1.35
ASOS…………..2.86
TOTAL PRECIPITATION FOR THE YEAR……….30.17  DEPARTURE……+3.49
ASOS………….31.73

PRELIMINARY CLIMATE SUMMARY FOR JUNE 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
M:    Missing data

6/01 78/62/70/+8/T/009/01            21 S   AERO 21 S   RMY N/A
6/02 79/54/67/+5/T/353/39            26 ENE AERO 25 ENE RMY 27
6/03 59/45/52/-10/0.00/816/90        28 ENE AERO 25 ENE RMY N/A
6/04 52/45/49/-14/0.82/000/00        29 ENE AERO 26 ENE RMY 29
6/05 64/47/56/-7/0.19/173/19         24 N   AERO 21 N   RMY 23  TSTM
6/06 66/50/58/-5/0.00/373/41         23 S   AERO 21 S   RMY 22
6/07 69/50/60/-4/0.00/282/31         25 S   AERO 25 S   RMY 27
6/08 79/52/66/+2/0.00/684/75         20 SW  AERO 17 SW  RMY 18
6/09 79/58/69/+5/0.00/767/84         22 W   AERO 21 W   RMY 22
6/10 72/56/64/-1/0.00/593/65         20 S   AERO 18 S   RMY 17
6/11 68/51/60/-5/0.00/594/65         21 ENE AERO 20 SSW RMY N/A
6/12 77/49/63/-2/0.00/814/89         37 SW  AERO 37 SW  RMY 39
6/13 74/56/65/0/T/284/31             35 SW  AERO 36 SW  RMY 36
6/14 77/61/69/+3/0.00/495/54         35 W   AERO 36 WNW RMY 37
6/15 68/53/61/-5/0.01/266/29         17 NNW AERO 16 WNW RMY 19
6/16 83/54/69/+3/0.00/761/83         25 NNW AERO 24 NNW RMY 25
6/17 86/63/75/+8/0.00/807/88         23 S   AERO 22 S   RMY N/A
6/18 86/64/75/+8/0.10/284/31         37 SSW AERO 37 SSW RMY 40  TSTM
6/19 81/64/73/+6/0.01/789/86         31 WSW AERO 32 WSW RMY 32
6/20 81/58/70/+2/0.00/459/50         22 W   AERO 21 W   RMY 23
6/21 81/62/72/+4/0.00/706/77         22 E   AERO 18 E   RMY 21
6/22 75/56/66/-2/0.00/…/..         24 ESE AERO 22 ESE RMY 24
6/23 65/55/60/-8/0.03/…/..         22 ENE AERO 21 NE  RMY 22
6/24 78/56/67/-2/…./…/..         21 SSW AERO 20 SSW RMY N/A
6/25 70/56/63/-6/…./…/..         30 N   AERO 29 N   RMY 31  TSTM
6/26 79/53/66/-3/0.00/…/..         24 SSW AERO 24 SSW RMY 25
6/27 78/59/69/0/…./…/..          26 S   AERO 28 S   RMY N/A
6/28 71/63/67/-3/…./000/00         28 S   AERO 26 S   RMY N/A TSTM
6/29 87/66/77/+7/0.00/…/..         18 W   AERO 16 W   RMY 18

6/30 Low temp since midnight is 69F; normal low is now 61F

DAILY RECORDS FOR JUNE 2018

None so far.

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

RECORDS FOR JUNE 30
HIGH 94F IN 1964
LOW 47F IN 1919
PRECIP 3.04 INS IN 1921
PEAK GUST 51 MPH WNW IN 1957

RECORDS FOR JULY 1
HIGH 98F IN 1964
LOW 44F IN 1988 [RECORD FOR MONTH] PRECIP 4.46 INS IN 1915 [RECORD FOR MONTH] PEAK GUST 52 MPH WNW IN 1974

TODAY’S REPORT PREPARED BY: Jonathan O’Brien