Monday, July 31, 2023
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
MONDAY, JULY 31, 2023
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0436E
SUNSET: 1905E
SPECTACULAR SUMMER WEATHER WITH SUNSHINE, WARM TEMPS, AND A
DRY AIR MASS…
It doesn’t get much better than this on the last day of July.
We have been rewarded with abundant sunshine with only some
“fair weather” cumulus clouds dotting the sky. Temperatures
have warmed into the upper 70s here on the hill, which is
a bit below normal for the date.
The best part of this weather is the relatively low dew
points which have dropped into the mid 50s this afternoon.
This is very refreshing air for this time of year, perfect
for any and all outdoor activities.
The wind has been picking up a bit this afternoon after being
on the light side most of the morning. The average speed for
the day is around 7mph, however its around 10mph for the last
couple of hours. A gust to 22mph occurred just before 2pm.
Visibility has been excellent today (and certainly excellent
for this time of year), ranging between 60-70 miles all day!
The maximum temperature so far today is 79F, this is 3 degrees
below the normal high of 82F. The minimum temperature today is
59F, which is 5 degrees below the normal low of 64F.
The monthly rainfall total of 9.58″ is now ranked 5th most for
the month of July. Here is the list of rankings per our Chief
Scientist Mike Iacono.
BHO Highest July Precipitation, inches (1886-2023):
1) 11.67 in 1938
2) 11.59 in 2021
3) 10.66 in 1988
4) 10.43 in 1921
5) 9.58 in 2023 (through 7/30)
6) 9.52 in 1915
7) 8.47 in 1889
8) 7.62 in 2009
————————————————————–
Today’s Observations:
7 A.M.
Weather: Clear, few altocumulus/castellanus all quadrants,
few cirrocumulus distant ESE-SSE
Temperature: 65F; Dew Point: 57F; Relative Humidity: 84%
Wind: W @ 6 kts, wind light
Sea-level pressure: 1015.0 mb; 29.97 in. Hg: steady, then rising
Visibility: 60 miles
6-hr Max temp: 65F
6-hr Min temp: 59F
24-hr Precip: 0.00 inches
BHO SA 1155 CLR 60 150/65/57/2806/997/ FEW AC/ACC ALQDS
FEW CC DSNT ESE-SSE WND LGT/ 8/089 53011 10065 20059
10 A.M.
Weather: Clear, few cumulus all quadrants
Temperature: 74F; Dew Point: 58F; Relative Humidity: 57%
Wind: WNW @ 4 kts, wind light
Sea-level pressure: 1015.2 mb; 29.98 in. Hg: steady, then rising
Visibility: 70 miles
3-hr Precip: 0.00 inches
BHO SA 1455 CLR 70 152/74/58/2904/998/ FEW CU ALQDS WND LGT/
8/200 53002
1 P.M.
Weather: Scattered cumulus, few cumulonimbus distant NNW-NNE,
virga distant NNW
Temperature: 78F; Dew Point: 54F; Relative Humidity: 43%
Wind: W @ 10G19 kts
Sea-level pressure: 1014.0mb; 29.94 in. Hg: falling, then more rapidly
Visibility: 70 miles
6-hr Max temp: 79F
6-hr Min temp: 65F
6-hr Precip: 0.00 inches
BHO SA 1755 60 SCT 70 140/78/54/2610G19/994/ FEW CB DSNT NNW-NNE
VIRGA DSNT NNW/ 8/360 58012 10079 20065
————————————————————–
SUMMARY FOR SUNDAY, JULY 30, 2023
TEMPERATURE (DEGREES F)
MAX…….75 NORMAL…..82
MIN…….56 NORMAL…..64
MEAN……66 NORMAL…..73
DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……….-7
TOTAL DEPARTURE FOR THE MONTH…………………+59 [+1.8 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON: JUL 2023 THRU JUN 2024)
TOTAL HEATING UNITS FOR YESTERDAY…………….0 DEPARTURE………0
TOTAL HEATING UNITS FOR THE MONTH…………….0 DEPARTURE……..-7
TOTAL HEATING UNITS FOR THE SEASON……………0 DEPARTURE……..-7
TOTAL HEATING UNITS LAST SEASON TO DATE……….0 DEPARTURE………0
COOLING DEGREE DAYS (SEASON: JAN 2023 THRU DEC 2023)
TOTAL COOLING UNITS FOR YESTERDAY…………….1 DEPARTURE……..-7
TOTAL COOLING UNITS FOR THE MONTH…………..289 DEPARTURE…….+49
TOTAL COOLING UNITS FOR THE SEASON………….417 DEPARTURE…….+38
TOTAL COOLING UNITS LAST SEASON TO DATE……..496 DEPARTURE…….-79
PEAK WIND GUST (MPH):
Note: Instruments designated #1 = Main Tower, #2 = South Tower,
F420C, Contacting, Merlin, and Richards are all Main Tower.
E=Estimated
F420C (Official)……….E24 N @ 12:31 A.M.
VECTOR #1 (1-Sec)……….24 NNW @ 12:16 A.M.
VECTOR #2 (1-Sec)……….24 N @ 12:06 A.M.
DAVIS #1……………….22 NNW @ 12:17 A.M.
DAVIS #2 ………………22 NNE @ 12:06 A.M.
RMY #1 (Instantaneous)…..25 NNW @ 03:45 A.M.
RMY #2 (Instantaneous)…..26 N @ 12:07 A.M.
MERLIN…………………M
RICHARDS (C5C) (Inst)……24 @ 02:44 A.M.
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………16 N @ 12:07 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..15 @ 02:45 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..16 @ 12:06 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………15 NW @ 02:45 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………16 N @ 12:07 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..15 NW @ 02:46 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..16 N @ 12:06 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………15 @ 02:45 A.M.
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…………8.2 SW [197 total miles]
VECTOR #1………………….8.6
VECTOR #2………………….8.8
DAVIS #1…………………..8.6 NW
DAVIS #2…………………..8.5 NNW
RMY #1…………………….8.4 NW
RMY #2…………………….8.6 NNW
RICHARDS (C5C)……………..9.0
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.12
TOTAL PRECIPITATION FOR THE MONTH…………..9.58 DEPARTURE…..+6.23
TOTAL PRECIPITATION FOR THE YEAR…………..34.76 DEPARTURE…..+4.18
————————————————————–
PRELIMINARY CLIMATE SUMMARY FOR JULY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN)/SUN(%)/PEAK GUST/VEC1/RMY GUST
PEAK GUST: F420C (Official)
VEC1: Vector #1 1-second gust
RMY: R.M. Young #1 wind gust recording system (Instantaneous)
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized
M: Missing data
7/1 80/61/71/0/0.00/567/62 17 SSE VEC1 16 SSE RMY 17
7/2 74/63/69/-2/0.34/027/03 35 S VEC1 35 S RMY 35
7/3 79/63/72/-1/0.40/265/29 18 NNW VEC1 18 NNW RMY 17 TSTM
7/4 71/65/68/-4/0.81/000/00 17 NE VEC1 18 NE RMY 17 TSTM
7/5 88/66/77/+5/0.00/720/79 17 S VEC1 16 SE RMY 15
7/6 92/69/81/+9/0.00/683/75 23 SSW VEC1 22 SSW RMY 23
7/7 87/70/78/+6/0.00/763/84 23 SW VEC1 22 SW RMY 23
7/8 84/70/77/+5/0.00/463/51 20 W VEC1 20 W RMY 19
7/9 81/69/75/+2/T/200/22 17 ESE VEC1 18 E RMY 17
7/10 71/66/69/-4/0.68/000/00 22 ESE VEC1 21 ESE RMY 22
7/11 85/62/74/+1/0.00/796/88 24 WNW VEC1 25 WNW RMY 25
7/12 91/70/81/+8/0.00/713/79 21 WSW VEC1 22 SSW RMY 20
7/13 88/67/78/+5/0.13/695/77 35 SSW VEC1 35 SSW RMY 38 TSTM
7/14 78/65/72/-1/0.18/342/38 29 SSW VEC1 32 SSW RMY 32 TSTM
7/15 86/70/78/+5/T/548/61 28 SSW VEC1 30 SSW RMY 29 TSTM
7/16 76/71/74/+1/2.56/000/00 40 S VEC1 41 SSW RMY 48 TSTM
7/17 86/71/79/+6/0.00/699/78 21 WSW VEC1 21 W RMY 23
7/18 84/70/77/+4/0.00/402/45 28 SSW VEC1 28 SSW RMY 27
7/19 83/68/76/+3/0.00/554/62 23 W VEC1 23 W RMY 22
7/20 82/64/73/+0/0.00/838/94 17 NNE VEC1 17 SE RMY 18
7/21 79/62/71/-2/1.99/178/20 30 NW VEC1 31 NW RMY 32 TSTM
7/22 81/64/73/0/0.00/656/74 15 W VEC1 14 W RMY 16
7/23 85/65/75/+2/0.00/805/91 21 NW VEC1 20 W RMY 21
7/24 85/67/76/+3/0.00/706/80 23 S VEC1 24 S RMY 24
7/25 85/64/75/+2/1.02/441/50 29 NNE VEC1 30 NNW RMY 29 TSTM
7/26 85/63/74/+1/0.00/817/93 23 W VEC1 23 W RMY 23
7/27 88/68/78/+5/0.43/368/42 61 WNW VEC1 63 WNW RMY 66 TSTM
7/28 88/68/78/+5/0.00/…/.. 23 SW VEC1 23 SW RMY 23
7/29 88/62/75/+2/1.04/…/.. 35 NNE VEC1 37 NNE RMY 36 TSTM
7/30 75/56/66/-7/0.00/…/.. 24 N VEC1 24 NNW RMY 25
7/31 The low since midnight is 59F, the daily normal low is 64F
DAILY RECORDS
07/16/2023: NEW RECORD DAILY PRECIPITATION OF 2.56 INCHES;
SURPASSES THE PREVIOUS RECORD OF 0.98 INCHES IN 2014
07/16/2023: NEW RECORD HIGH DAILY MINIMUM TEMPERATURE OF 71F;
TIES THE RECORD OF 71F SET IN 1901, 1958, 1968, AND 2013
07/27/2023: NEW RECORD PEAK WIND GUST OF 61 MPH WNW;
BEATS THE OLD RECORD OF 47 MPH ENE SET IN 1984
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR JULY 31
HIGH 95F IN 1917
LOW 50F IN 1895
PRECIP 1.34 INS IN 1892
PEAK GUST 43e MPH WNW SW IN 1953, 43 SW IN 1971
RECORDS FOR AUGUST 1
HIGH 97F IN 1917
LOW 49F IN 1891
PRECIP 3.61 INCHES IN 1927
PEAK GUST 41 MPH NNW IN 1985
TODAY’S REPORT PREPARED BY: Matt Douglas
