Sunday, July 18, 2021

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

SUNDAY, JULY 18, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0424E
SUNSET:  1917E

FOGGY AND COOLER WITH INTERMITTENT RAINFALL
ATOP GREAT BLUE HILL….

We observed some showers this morning following the rain
yesterday which amounted to 0.41 inches by 7 A.M. The
showers today left 0.07 inches so far. This brings
the monthly rain total to 10.37 inches. That’s
a monthly surplus of 8.47 inches and a yearly of 4.88
inches.
 
Visibility is poor to say the least at a 1/4th mile
with fog being a factor all day.  

The high so far today is 74F, 8 degrees under the daily
average of 82F. The low so far today is 64F, which is
the same as the daily average minimum.

On a side note, the renovations have begun in earnest this week.
We are no longer operating out of the tower and have moved to
another part of the building. All wind instruments on the main
tower have been taken offline and will remain so until further
notice. Please be patient with us as we navigate through our
new routine. Data at times may be delayed.

———————————————–

Today’s Observations:

7 A.M.
Weather: Fog, vertical visibility 300 feet
Temperature: 71F; Dew Point: 71F; Relative Humidity: 100%
Wind: S @ 9 kts
Sea-level pressure: 30.02 in. Hg; steady, then rising
Visibility: 1/8th mile, fog
6-hr Max temp: 71F
6-hr Min temp: 66F
24-hr Precip: 0.41 in.
BHO SA 1155 X W3 1/8F 167/71/71/1909/002/ 8//// 70041
51004 10071 20066

10 A.M.
Weather: Fog, vertical visibility 200 ft
Temperature: 71F; Dew Point: 71F; Relative Humidity: 100%
Wind: NW @ 7 kts
Sea-level pressure: 30.02 in Hg; steady then falling
Visibility: 1/16th mile, fog
3-hr Precip: 0.06 ins.
BHO SA 1455 X W2 1/16LF 165/71/71/3207/002/ 8//// 6004/
57002


1 P.M.
Weather: Scattered Cumulus, thin broken cirrostratus
(cumulonimbus distant SE)
Temperature: 77F, Dew point: 70F; Relative Humidity: 80%
Wind: ENE @ 8 kts  
Sea-level pressure: 30.10 in Hg; falling then rising
Visibility: 50 miles
6-hr Max temp: 78F
6-hr Min temp: 69F
6-hr Precip: 0.04 ins.

 

SUMMARY FOR SATURDAY, JULY 17, 2021

TEMPERATURE (DEGREES F)
MAX…….78     NORMAL…..82
MIN…….64     NORMAL…..64
MEAN……71     NORMAL…..73

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……….-2
TOTAL DEPARTURE FOR THE MONTH…………………-71 [-4.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2021 THRU JUN 2022)
TOTAL HEATING UNITS FOR YESTERDAY…………….0  DEPARTURE………0
TOTAL HEATING UNITS FOR THE MONTH……………26  DEPARTURE…….+22
TOTAL HEATING UNITS FOR THE SEASON…………..26  DEPARTURE…….+22
TOTAL HEATING UNITS LAST SEASON TO DATE……….1  DEPARTURE…….+25

COOLING DEGREE DAYS (SEASON: JAN 2021 THRU DEC 2021)
TOTAL COOLING UNITS FOR YESTERDAY…………….6  DEPARTURE…….-2
TOTAL COOLING UNITS FOR THE MONTH……………83  DEPARTURE……-47
TOTAL COOLING UNITS FOR THE SEASON………….309  DEPARTURE……+40
TOTAL COOLING UNITS LAST SEASON TO DATE……..299  DEPARTURE……+10

PEAK WIND GUST (MPH):
                     Official……………….26 ENE @ 5:43 P.M.
                     AEROVANE (south tower)…..25 ENE @ 5:42 P.M.
                     VECTOR #2 (south tower)….27     @ 5:43 P.M.
                     DAVIS #2 (south tower)…..23 ENE @ 5:44 P.M.
                     ASOS………..OUT OF SERVICE D/T RENOVATIONS
                     VECTOR #1……OUT OF SERVICE D/T RENOVATIONS
                     DAVIS #1…….OUT OF SERVICE D/T RENOVATIONS
                     RMY…………OUT OF SERVICE D/T RENOVATIONS  
                     MERLIN………OUT OF SERVICE D/T RENOVATIONS


FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………17 ENE @ 4:37 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..18     @ 4:22 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………18 ENE @ 4:37 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE…….OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE…OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE..OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE RMY AVERAGE……..OUT OF SERVICE D/T RENOVATIONS

AVERAGE WIND SPEED AND DIRECTION:
                     CONTACTING/OFFICIAL…….9.4 NE [226 total miles]                     VECTOR #2…………….10.2
                     DAVIS #2……………..10.1 ENE
                     RMY……………..OUT OF SERVICE D/T RENOVATIONS
                     ASOS…………….OUT OF SERVICE D/T RENOVATIONS
                     VECTOR #1………..OUT OF SERVICE D/T RENOVATIONS
                     DAVIS #1…………OUT OF SERVICE D/T RENOVATIONS   

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.41  DEPARTURE….+0.30
TOTAL PRECIPITATION FOR THE MONTH…………10.37  DEPARTURE….+8.47
TOTAL PRECIPITATION FOR THE YEAR………….33.75  DEPARTURE….+4.88

 

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


07/01   80/65/73/+2/0.74/155/17           22 W   AERO 20 WSW  RMY 21
07/02   65/55/60/-11/1.49/000/00          37 NE  AERO 36 NE   RMY 39
07/03   56/54/55/-17/1.98/000/00          41 NE  AERO 44 NE   RMY 45 TSTM
07/04   66/54/60/-12/0.16/191/21          26 ENE AERO 23 ENE  RMY 26
07/05   74/53/64/-8/0.01/546/60           26 SSW AERO 28 SSW  RMY 27
07/06   87/66/77/+5/0.26/255/28           37 W   AERO 48 W    RMY 38 TSTM
07/07   88/88/77/+5/0.77/699/77           63 NW  AERO 75 NW   RMY 70 TSTM
07/08   67/59/63/-9/0.38/109/12           46 W   AERO 46 W    RMY 51 TSTM
07/09   73/62/68/-5/3.02/163/18           40 WNW AERO 44 WNW  RMY 43
07/10   71/63/67/-6/0.07/109/12           23 NE  AERO 21 NNE  RMY 22
07/11   81/61/71/-2/T/325/36              21 SW  AERO 19 S    RMY N/A
07/12   67/61/64/-9/1.01/000/00           31 ENE AERO 31 ENE  RMY N/A
07/13   66/60/63/-10/0.02/…/..          19 E   AERO 18 E    RMY N/A
07/14   80/62/71/-2/0.01/…/..           19 S   AERO 18 S    RMY N/A
07/15   88/67/78/+5/0.00/…/..           19 WSW AERO 18 SSW  RMY N/A
07/16   90/70/80/+7/…./…/..           36 NNW AERO 39 NNW  RMY N/A
07/17   78/64/71/-2/…./…/..           26 ENE AERO 25 ENE  RMY N/A

07/18   The low since midnight is 64F, the daily normal low is 64F

RECORDS FOR JULY:
JULY 2: Record daily precipitation of 1.49″,
        Surpasses previous record of 1.42″ set in 1986

JULY 3: Record daily precipitation of 1.98″,
        Surpasses previous record of 1.36″ set in 1985

JULY 7: Record peak gust of 63 MPH,
        Surpasses previous record of 55 MPH set in 1989


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

RECORDS FOR JULY 18
HIGH 96F IN 1991, 1999
LOW 54F IN 1892, 1956, 1971
PRECIP 1.65 INS IN 2000
WIND 43e MPH SW IN 1949

RECORDS FOR JULY 19
HIGH 96F IN 1977, 1991
LOW 50F IN 1890
PRECIP 1.10 INS IN 1951
WIND 63 MPH SSW IN 1982

TODAY’S REPORT PREPARED BY: Benjamin Turner