Friday, July 21, 2017

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, JULY 21, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME

DRY HEAT CONTINUES TO WARM GREAT BLUE HILL

Another warm day on top of Great Blue Hill. We had a high of 88F which
is above the normal temperature of 81F. We have been dry here as well
with dew points and humidity dropping throughout the day to make for a
pleasant afternoon. Winds coming from the west/northwest remained light
in the morning but has slightly picked up this afternoon with a peak gust
of 21 MPH by 1PM EST. Skies were clear with only a few clouds during the
observations.

Today’s Observations:

7 A.M.
Weather: Clear sky, few altocumulus SE-SSW, few cirrostratus all
directions
Temperature: 73F; Dew Point: 61F; Wind: WNW at 6 kts,
Wind: Light
Sea-level pressure: 29.87 ins. Hg, rising, then more slowly
Visibility: 45 miles
6-hr Max temp: 75F
6-hr Min temp: 68F
24-hr precip: 0.00 in.
BHO SA 1155 CLR 45 116/73/61/3006/987/ FEW AC SE-SSW FEW CS ALQDS
WND LGT/ 8/085 52008 10075 20068

10 A.M.
Weather: Few cumulus NE
Temperature: 81F; Dew Point: 58F; Wind: WNW at 4 kts,
Wind: Light
Sea-level pressure: 29.88 ins. Hg, rising then steady
Visibility: 50 miles
BHO SA 1455 CLR 50 118/81/58/E3004/988/ FEW CU NE WND LGT/ 8/100
50002

1 P.M.
Weather: Clear, few cumulus S-W, few cirrus all directions
Temperature: 86F; Dew Point: 59F; Wind: WSW at 7G14 kts
Sea-level pressure: 29.83 ins. Hg, falling, then more quickly
Visibility: 50 miles
6-hr Max temp: 88F
6-hr Min temp: 73F
BHO SA 1755 CLR 50 103/86/59/2507G14/983/ FEW CU S-W FEW CI ALQDS/
8/102 58015 10088 20073

SUMMARY FOR THURSDAY, JULY 20, 2017

TEMPERATURE (DEGREES F)
MAX…..90   NORMAL…..81
MIN…..70   NORMAL…..63
MEAN….80   NORMAL…..72

DEPARTURE FROM 30-YEAR NORMAL…………………….+8
TOTAL DEPARTURE FOR THE MONTH……………………+31 [+1.6 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..15   DEPARTURE……….-8
TOTAL COOLING UNITS FOR THE MONTH………….170   DEPARTURE………+33
TOTAL COOLING UNITS FOR THE SEASON…………371   DEPARTURE……..+105
TOTAL COOLING UNITS LAST SEASON TO DATE…….323   DEPARTURE………+48

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….21 WSW  AT 12:36 P.M.
AERO……………………22 WSW  AT  4:27 P.M.
ASOS……………………21 W    AT 12:36 P.M.
DAVIS…………………..19 WSW  AT  4:17 P.M. RMY 21
FASTEST MILE FOR YESTERDAY…………………15 WSW  AT  4:27 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………15 W    AT  4:27 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..14 W    AT 12:37 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..8.0 W
ASOS…………………..8.0
DAVIS………………….6.4 W   [265 DEG.] *last of multiple occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.13
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.58  DEPARTURE……-0.88
ASOS…………..1.55
TOTAL PRECIPITATION FOR THE YEAR……….32.95  DEPARTURE……+3.52
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR JULY 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

7/1  85/67/76/+6/T/439/48                  35 S   AERO 37 S   RMY 38
7/2  87/69/78/+8/T/785/86                  25 W*  AERO 28 W*  RMY 27
7/3  85/67/76/+5/0.00/894/98               28 W*  AERO 29 W   RMY 30
7/4  84/62/73/+2/0.00/783/86               17 W   AERO 17 W   RMY 18
7/5  82/62/72/+1/0.00/855/94               20 S   AERO 20 ENE RMY 20
7/6  82/60/71/+0/0.00/664/73               21 SSW AERO 22 SSW RMY 21
7/7  71/60/66/-5/0.63/000/00               28 ENE AERO 28 ENE RMY 27
7/8  84/61/73/+1/0.15/463/51               30 SW* AERO 32 SSW RMY 33 TSTM
7/9  81/60/71/-1/0.00/897/99               26 W   AERO 26 W   RMY 26
7/10 85/63/74/+2/T/751/83                  25 SW  AERO 25 S   RMY 26
7/11 82/66/74/+2/0.25/253/28               24 S   AERO 24 S   RMY N/A
7/12 85/68/77/+5/0.43/325/36               23 NE  AERO 22 NE  RMY 23 TSTM
7/13 68/55/62/-10/0.03/000/00              28 NNE AERO 28 NE  RMY 29
7/14 63/56/60/-12/0.02/…/..              15 E   AERO 14 E   RMY 14
7/15 80/60/70/-2/0.00/…/..               18 S   AERO 16 S   RMY 18
7/16 87/64/76/+4/0.00/…/..               18 SSE AERO 16 E   RMY 17
7/17 84/68/76/+4/0.00/…/..               25 S   AERO 25 S*  RMY 25
7/18 85/68/77/+5/0.07/…/..               23 S   AERO 23 S   RMY 23
7/19 90/70/80/+8/0.00/…/..               22 SW  AERO 22 SW* RMY 22
7/20 90/70/80/+8/0.00/…/..               21 WSW AERO 22 WSW RMY 21

7/20 Low temp since midnight is 68F; normal low is now 63F

DAILY RECORDS FOR JULY

None so far.

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

RECORDS FOR JULY 21
HIGH 100F IN 1977 [RECORD FOR MONTH] LOW 48F IN 1890
PRECIP 2.09 INS IN 1938
PEAK GUST 60e MPH WNW IN 1977

RECORDS FOR JULY 22
HIGH 99F IN 1926, 2011
LOW 52F IN 1890
PRECIP 1.73 INS IN 1900
PEAK GUST 55 MPH IN 1983

TODAY’S REPORT PREPARED BY: Kaitlin Geagan