Tuesday, August 20, 2024

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

TUESDAY, AUGUST 20, 2024
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0457E
SUNSET:  1837E

A PERIOD OF LIGHT RAIN EARLY THIS MORNING, OTHERWISE A MAINLY
CLOUDY, COOLER, AND LESS HUMID DAY IN PROGRESS….

A cold front moved through the area during the predawn hours
with cooler and much less humid air behind it. However an area
of anafrontal (after the front) light rain moved through between
5-8am this morning. Since then, skies have filled with mainly
diurnal cloud cover leaving us with generally cloudy skies into
this afternoon.

Temperatures are cooler today, recovering into the upper 60s
early this afternoon after bottoming out in the mid to upper
50s this morning. The dew point, which briefly reached the mid
70s last evening, has dropped into the mid 50s today. The air
has a little touch of a fall feel to it this afternoon with a
nice breeze blowing.

The wind has been a bit busy today with an average speed so far
for the day around 12mph. Frequent gusts of 20-25mph have been
occurring since early this morning. The peak gust for the day
thus far is 32mph which occurred just before 3am this morning.

Visibility has been excellent most of the day, especially once
the rain moved out. A variable visibility of 8-50 miles early
this morning has improved to around 70 miles for the balance
of the day. Another notable aspect of the day is the lack of
any wildfire smoke, finally!

The maximum temperature so far today is 69F, which is 11 degrees
below the normal high of 80F. The minimum temperature since
midnight is 57F, which is 5 degrees above the normal low of 62F.

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Today’s Observations:

7 A.M.
Weather: Overcast altostratus, light rain, few breaks in overcast
distant WSW-NNW, few stratus fractus all quadrants
Temperature: 57F; Dew Point: 56F; Relative Humidity: 96%
Wind: NW @ 10G16 kts
Sea-level pressure: 1008.5 mb ; 29.78 in. Hg: rising, then more rapidly
Visibility: 25 miles, 50 W-NW, 20 N-NE, 8 ESE-SSW, thin fog
6-hr Max temp: 65F
6-hr Min temp: 57F
24-hr Precip:  0.09 inches
BHO SA 1155 E90 OVC 25R- 085/57/56/3110G16/978/ FEW BINOVC DSNT WSW-NNW
FEW STFRA ALQDS THN F ALQDS VSBY 50 W-NW 20 N-NE 8 ESE-SSW/ 8/72/ 53012
6005/ 70009 10065 20057

10 A.M.
Weather: Broken stratocumulus, broken altocumulus/altostratus
Temperature: 65F; Dew Point: 55F; Relative Humidity: 69%
Wind: WNW @ 11G18 kts
Sea-level pressure: 1009.6 mb; 29.81 in. Hg: rising, then more rapidly
Visibility: 70 miles
3-hr Precip: 0.02 inches
BHO SA 1455 E20 BKN 100 BKN 70 096/65/55/2911G18/981/ 8/570 53011 6002/

1 P.M.
Weather: Overcast stratocumulus, few breaks in overcast all quadrants
Temperature: 66F; Dew Point: 55F; Relative Humidity: 67%
Wind: NW @ 11G18 kts
Sea-level pressure: 1010.3 mb; 29.83 in. Hg: rising, then more rapidly
Visibility: 70 miles
6-hr Max temp: 69F
6-hr Min temp: 57F
6-hr Precip: 0.02 inches
BHO SA 1755 E27 OVC 70 103/66/55/3211G18/983/ FEW BINOVC ALQDS/
8/5// 53007 6002/ 10069 20057

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SUMMARY FOR MONDAY, AUGUST 19, 2024

TEMPERATURE (DEGREES F)
MAX…….78  NORMAL…..80
MIN…….66  NORMAL…..63
MEAN……72  NORMAL…..71

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………..+1
TOTAL DEPARTURE FOR THE MONTH……………………..+6 [+0.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY…………….0  DEPARTURE………0
TOTAL HEATING UNITS FOR THE MONTH…………….2  DEPARTURE……..-3
TOTAL HEATING UNITS FOR THE SEASON……………2  DEPARTURE…….-10
TOTAL HEATING UNITS LAST SEASON TO DATE……….0  DEPARTURE……..+2

COOLING DEGREE DAYS (SEASON: JAN 2024 THRU DEC 2024)
TOTAL COOLING UNITS FOR YESTERDAY…………….7  DEPARTURE………0
TOTAL COOLING UNITS FOR THE MONTH…………..146  DEPARTURE……..+5
TOTAL COOLING UNITS FOR THE SEASON………….643  DEPARTURE……+116
TOTAL COOLING UNITS LAST SEASON TO DATE……..524  DEPARTURE……+119

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)……….E23 SSW  @   07:26 P.M.
VECTOR #1 (1-Sec)……….23 SSW  @   07:33 P.M.
VECTOR #2 (1-Sec)……….25 SSW  @   07:32 P.M.
DAVIS #1……………….22 SSW  @   07:23 P.M.
DAVIS #2 ………………26 S    @   05:43 P.M.
RMY #1 (Instantaneous)…..22 SSW  @   07:26 P.M.
RMY #2 (Instantaneous)…..26 SSW  @   07:32 P.M.
MERLIN………………….M
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………15 S    @   06:00 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..15      @   07:34 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..16      @   07:34 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………15 S    @   07:27 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………18 S    @   05:55 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..15 SSW  @   07:34 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..16 SSW  @   07:34 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…….6.5 SSE [156 total miles] VECTOR #1……………..7.1
VECTOR #2……………..7.6
DAVIS #1………………6.8 S
DAVIS #2………………7.4 S
RMY #1………………..6.9 S
RMY #2………………..7.7 SSE
RICHARDS (C5C)…………OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.09 DEPARTURE…..-0.03
TOTAL PRECIPITATION FOR THE MONTH…………..2.94 DEPARTURE…..+0.48
TOTAL PRECIPITATION FOR THE YEAR (2024)…….41.19 DEPARTURE…..+8.03

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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  The low since midnight is 57F, 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 20
HIGH 94F IN 2022
LOW 48F IN 1896, 1905, 1949
PRECIP 2.71 INCHES IN 1970
PEAK GUST 47 MPH W IN 1983, 47 SSW IN 2010

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

TODAY’S REPORT PREPARED BY: Matt Douglas