Wednesday, August 21, 2024

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

WEDNESDAY, AUGUST 21, 2024
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0458E
SUNSET:  1835E

A MIX OF SUN AND CLOUDS WITH COOLER THAN NORMAL TEMPERATURES
AND A VERY COMFORTABLE AIR MASS….

A little taste of early fall today across the region with cooler
than normal temperatures and very comfortable humidity levels.
Skies started the day mainly on the clear side, however as low
level heating took place, convective cumulus clouds have
developed giving us a partly cloudy sky early this afternoon.

Temperatures are almost 10 degrees below normal early this
afternoon with readings in the low 70s. The dew point has been
holding in the low to mid 50s making for a very pleasant
feel to the air.

The wind was steady during the predawn hours, then went light
for a time during the mid to late morning hours, but is now
picking up a bit thanks to mixing from aloft. The average
speed for the day so far is around 9mph. The peak gust thus far
is 20mph, which occurred just before noon time.

Visibility has been quite decent today, holding at around 60 miles
most of the day.

The maximum temperature so far today is 72F, which is 8 degrees
below the normal high of 80F. The minimum temperature since
midnight is 51F, which is 11 degrees below the normal low of 62F.

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Today’s Observations:

7 A.M.
Weather: Clear, few altocumulus/castellanus distant WSW-N-E, thin
smoke layer aloft all quadrants
Temperature: 56F; Dew Point: 52F; Relative Humidity: 88%
Wind: W @ 7 kts
Sea-level pressure: 1015.0 mb ; 29.97 in. Hg: rising, then more slowly
Visibility: 60 miles
6-hr Max temp: 56F
6-hr Min temp: 51F
24-hr Precip:  0.02 inches
BHO SA 1155 CLR 60 150/56/52/2807/997/ FEW AC/ACC DSNT WSW-N-E
THN K LYR ALF ALQDS/ 8/080 51009 70002 10056 20051

10 A.M.
Weather: Broken cumulus, towering cumulus distant NNE-NE, thin smoke
layer aloft all quadrants
Temperature: 66F; Dew Point: 54F; Relative Humidity: 65%
Wind: WSW @ 5 kts, wind light and variable
Sea-level pressure: 1015.6 mb; 29.99 in. Hg: rising, then more rapidly
Visibility: 60 miles
3-hr Precip: 0.00 inches
BHO SA 1455 E30 BKN 60 156/66/54/2505/999/ TCU DSNT NNE-NE
THN K LYR ALF ALQDS WND L/V/ 8/200 53006

1 P.M.
Weather: Scattered cumulus, scattered altocumulus, virga distant NW-N,
thin smoke layer aloft distant SE-S
Temperature: 70F; Dew Point: 54F; Relative Humidity: 55%
Wind: W @ 8G16 kts
Sea-level pressure: 1015.1 mb; 29.98 in. Hg: falling, then more slowly
Visibility: 60 miles
6-hr Max temp: 72F
6-hr Min temp: 56F
6-hr Precip: 0.00 inches
BHO SA 1755 35 SCT 55 SCT 60 151/70/54/2708G16/998/ VIRGA DSNT NW-N
THN K LYR ALF DSNT SE-S/ 8/260 56005 10072 20056

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SUMMARY FOR TUESDAY, AUGUST 20, 2024

TEMPERATURE (DEGREES F)
MAX…….69  NORMAL…..80
MIN…….54  NORMAL…..62
MEAN……62  NORMAL…..71

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………..-9
TOTAL DEPARTURE FOR THE MONTH……………………..-3 [-0.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY…………….3  DEPARTURE……..+3
TOTAL HEATING UNITS FOR THE MONTH…………….5  DEPARTURE………0
TOTAL HEATING UNITS FOR THE SEASON……………5  DEPARTURE……..-7
TOTAL HEATING UNITS LAST SEASON TO DATE……….0  DEPARTURE……..+5

COOLING DEGREE DAYS (SEASON: JAN 2024 THRU DEC 2024)
TOTAL COOLING UNITS FOR YESTERDAY…………….0  DEPARTURE……..-7
TOTAL COOLING UNITS FOR THE MONTH…………..146  DEPARTURE……..-1
TOTAL COOLING UNITS FOR THE SEASON………….643  DEPARTURE……+109
TOTAL COOLING UNITS LAST SEASON TO DATE……..529  DEPARTURE……+114

PEAK WIND GUST (MPH):
Note: Instruments designated #1 = Main Tower, #2 = South Tower,
F420C, Contacting, Merlin, and Richards are all on Main Tower.
E=Estimated

F420C (Official)……….E32 NW   @   02:58 A.M.
VECTOR #1 (1-Sec)……….32 NW   @   02:58 A.M.
VECTOR #2 (1-Sec)……….30 NW   @   03:10 A.M.
DAVIS #1……………….29 NW   @   02:58 A.M.
DAVIS #2 ………………27 NW   @   03:10 A.M.
RMY #1 (Instantaneous)…..33 NW   @   02:58 A.M.
RMY #2 (Instantaneous)…..31 NW   @   08:54 A.M.
MERLIN…………………31 NW
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………26 NW   @   03:00 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..20      @   03:00 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..19      @   03:00 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………20 NW   @   03:00 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………19 NNW  @   03:01 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..20 NW   @   03:00 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..19 NW   @   03:00 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……11.1 NW [267 total miles] VECTOR #1…………….11.1
VECTOR #2…………….11.8
DAVIS #1……………..11.4 NW
DAVIS #2……………..11.5 NW
RMY #1……………….10.8 NW
RMY #2……………….11.5 NW
RICHARDS (C5C)…………OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.02 DEPARTURE…..-0.11
TOTAL PRECIPITATION FOR THE MONTH…………..2.96 DEPARTURE…..+0.37
TOTAL PRECIPITATION FOR THE YEAR (2024)…….41.21 DEPARTURE…..+7.92

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PRELIMINARY CLIMATE SUMMARY FOR AUGUST 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

8/1   92/71/82/+9/T/779/90                24 W   VEC1 24 W   RMY 23
8/2   94/73/84/+11/0.01/579/67            31 SSW VEC1 31 SSW RMY 30 TSTM
8/3   92/75/84/+11/0.00/612/71            29 W   VEC1 28 W   RMY 28
8/4   85/68/77/+4/0.20/318/37             29 WSW VEC1 29 WSW RMY 31 TSTM
8/5   90/67/79/+6/T/686/80                28 SSW VEC1 28 SSW RMY 29
8/6   73/60/67/-6/0.56/009/01             26 ENE VEC1 26 ENE RMY 26
8/7   69/57/63/-10/0.18/119/14            25 NE  VEC1 23 NE  RMY 23
8/8   72/58/65/-7/0.09/187/22             20 ESE VEC1 20 ESE RMY 19
8/9   82/62/72/0/0.48/127/15              50 SSW VEC1 48 S   RMY 50
8/10  85/68/77/+5/0.37/659/78             41 SSW VEC1 41 SSW RMY 43
8/11  81/63/72/0/0.00/741/88              30 W   VEC1 29 SW  RMY 30
8/12  77/59/68/-4/0.15/638/76             35 WNW VEC1 34 WNW RMY 36
8/13  80/58/69/-3/0.00/787/94             21 NW  VEC1 22 NW  RMY 21
8/14  82/62/72/0/0.00/676/81              16 NNW VEC1 15 NNW RMY 15
8/15  84/62/73/+1/0.57/…/..             44 N   VEC1 42 N   RMY 46 TSTM
8/16  74/61/68/-4/0.00/…/..             13 ESE VEC1 13 ESE RMY 13
8/17  75/60/68/-4/0.00/…/..             17 SE  VEC1 16 SE  RMY 15
8/18  71/62/67/-4/0.09/…/..             18 SE  VEC1 19 SE  RMY 17
8/19  78/66/72/+1/0.19/…/..             23 SSW VEC1 23 SSW RMY 22 TSTM
8/20  69/54/62/-9/0.07/…/..             32 NW  VEC1 32 NW  RMY 33

8/21  The low since midnight is 51F, the daily normal low is 62F.

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AUGUST DAILY RECORDS TO DATE

8/3  RECORD HIGH MINIMUM TEMPERATURE OF 75F,
TIED THE PREVIOUS RECORD SET IN 2020

8/15 PEAK GUST 44e MPH N,
TIED THE PREVIOUS RECORD SET IN 1941

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

RECORDS FOR AUGUST 21
HIGH 92F IN 1937, 1995
LOW 47F IN 1982
PRECIP 2.84 INCHES IN 1888
PEAK GUST 54 MPH WSW IN 2004

RECORDS FOR AUGUST 22
HIGH 90F IN 1939
LOW 42F IN 1894
PRECIP 2.28 INCHES IN 1935
PEAK GUST 47 MPH ESE IN 2021 [TROPICAL STORM HENRI]

TODAY’S REPORT PREPARED BY: Matt Douglas