Tuesday, September 17, 2024
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
TUESDAY, SEPTEMBER 17, 2024
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0527E
SUNSET: 1749E
EARLY MORNING FOG QUICKLY BURNS OFF TO MAINLY SUNNY SKIES…
We started the day socked in fog with visibility as low as 1/8th
of a mile for a time. The fog dissipated on the summit, but remained
socked in down below for a time this morning, which created a
complete undercast. Only the tops of hills and the very top of a
few of the skyscrapers in Boston could be seen. Meanwhile the sky
above only had thin scattered cirrus and plenty of sunshine.
All of the low clouds and fog quickly dissipated by mid morning
leaving us with another splendid early fall day. However cirrus
clouds have been increasing and thickening as we progress
through the afternoon, filtering the sun quite a bit by the 1pm
observation.
Temperatures have once again reached above normal levels as readings
have reached the low 80s early this afternoon. The dew point started
the day on the high side with readings in the upper 50s to near 60,
however as we push into the early afternoon hours, values have
dropped into the upper 40s thanks to some mixing from aloft.
The wind is on the light and variable side again today. The average
speed for the day so far is only around 5mph. The peak gust so far
is 14mph, which occurred around 1am this morning.
Visibility started the day obscured by fog. Once the fog cleared
from the summit, the visibility shot up to around 60 miles above
the undercast. It has generally held between 50-60 miles for the
balance of the day to this point.
The maximum temperature so far today is 82F, which is 10 degrees
above the normal high of 72F. The minimum temperature since midnight
is 55F, which is equal to the normal low of 55F.
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Today’s Observations:
7 A.M.
Weather: Thin scattered cirrus, complete undercast all quadrants
Temperature: 58F; Dew Point: 57F; Relative Humidity: 98%
Wind: WNW @ 5 kts, wind light
Sea-level pressure: 1025.4 mb; 30.28 in. Hg: rising, then steady
Visibility: 1/2 mile, fog, 60 miles above undercast
6-hr Max temp: 5F8
6-hr Min temp: 55F
24-hr Precip: 0.00 inches
BHO SA 1155 ///OVC 250 -SCT 1/2F 254/58/57/2905/028/ COMPLETE UNDERCAST
ALQDS VSBY 60 ABV UNDERCAST WND LGT/ 8/601 51002 10058 20055
10 A.M.
Weather: Thin scattered cirrus
Temperature: 73F; Dew Point: 59F; Relative Humidity: 61%
Wind: S @ 2 kts, wind light and variable
Sea-level pressure: 1024.9 mb; 30.27 in. Hg: steady, then falling
Visibility: 50 miles, hazy
3-hr Precip: 0.00 inches
BHO SA 1455 250 -SCT 50 249/73/59/1702/027/ HAZY WND L/V/ 8/001 58005
1 P.M.
Weather: Broken cirrus
Temperature: 82F; Dew Point: 49F; Relative Humidity: 32%
Wind: SSW @ 3 kts, wind light
Sea-level pressure: 1023.8 mb; 30.23 in. Hg: falling unsteadily
Visibility: 60 miles
6-hr Max temp: 82F
6-hr Min temp: 58F
6-hr Precip: 0.00 inches
BHO SA 1755 E250 BKN 60 238/82/49/2003/023/ WND LGT/ 8/004 57011
10082 20058
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SUMMARY FOR MONDAY, SEPTEMBER 16, 2024
TEMPERATURE (DEGREES F)
MAX…….83 NORMAL…..73
MIN…….55 NORMAL…..56
MEAN……69 NORMAL…..64
DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………..+5
TOTAL DEPARTURE FOR THE MONTH…………………….+13 [+0.6 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY…………….0 DEPARTURE……..-3
TOTAL HEATING UNITS FOR THE MONTH……………10 DEPARTURE…….-18
TOTAL HEATING UNITS FOR THE SEASON…………..21 DEPARTURE…….-25
TOTAL HEATING UNITS LAST SEASON TO DATE………12 DEPARTURE……..+9
COOLING DEGREE DAYS (SEASON: JAN 2024 THRU DEC 2024)
TOTAL COOLING UNITS FOR YESTERDAY…………….4 DEPARTURE……..+2
TOTAL COOLING UNITS FOR THE MONTH……………51 DEPARTURE……..-5
TOTAL COOLING UNITS FOR THE SEASON………….745 DEPARTURE…….+94
TOTAL COOLING UNITS LAST SEASON TO DATE……..689 DEPARTURE…….+56
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)……….E22 SSW @ 08:09 P.M.
VECTOR #1 (1-Sec)……….21 SSW @ 08:09 P.M.
VECTOR #2 (1-Sec)……….20 S @ 08:08 P.M.
DAVIS #1……………….20 S @ 07:43 P.M.
DAVIS #2 ………………21 S @ 06:44 P.M.
RMY #1 (Instantaneous)…..21 SSW @ 08:09 P.M.
RMY #2 (Instantaneous)…..21 S @ 08:08 P.M.
MERLIN…………………19 SSW
RICHARDS (C5C) (Inst)…..OTS
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………16 SSW @ 08:14 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..14 @ 08:13 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..14 @ 08:15 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………14 S @ 08:23 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………16 S @ 06:54 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..14 SSW @ 08:13 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..15 S @ 08:15 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..6.3 SSW [152 total miles]
VECTOR #1………………7.1
VECTOR #2………………7.3
DAVIS #1……………….6.7 SSW
DAVIS #2……………….6.9 SW
RMY #1…………………7.0 SW
RMY #2…………………7.3 SW
RICHARDS (C5C)………….OTS
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.14
TOTAL PRECIPITATION FOR THE MONTH…………..0.04 DEPARTURE…..-1.93
TOTAL PRECIPITATION FOR THE YEAR (2024)…….41.25 DEPARTURE…..+4.67
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PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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
9/1 82/67/75/+6/T/244/31 28 SSW VEC1 27 SW RMY 28
9/2 79/56/68/-1/0.00/644/82 31 NNW VEC1 31 NNW RMY 32
9/3 74/49/62/-6/0.00/766/98 23 NW VEC1 23 NNW RMY 23
9/4 80/56/68/0/0.00/732/94 18 ESE VEC1 19 SE RMY 18
9/5 77/58/68/0/0.00/737/95 20 ESE VEC1 19 ESE RMY 19
9/6 73/58/66/-2/0.00/240/31 22 E VEC1 21 ENE RMY 23
9/7 77/56/67/0/0.04/301/39 34 WNW VEC1 31 WNW RMY 33
9/8 70/50/60/-7/0.00/753/98 35 W VEC1 35 W RMY 34
9/9 75/51/63/-4/0.00/727/95 31 WNW VEC1 28 WNW RMY 30
9/10 78/56/67/+1/0.00/717/94 21 NW VEC1 20 SW RMY 21
9/11 78/53/66/0/0.00/714/94 20 S VEC1 19 S RMY 18
9/12 82/58/70/+4/0.00/…/.. 20 S VEC1 19 S RMY 20
9/13 85/59/72/+7/0.00/…/.. 21 SSW VEC1 20 SSW RMY 20
9/14 81/61/71/+6/0.00/…/.. 21 ENE VEC1 20 ENE RMY 21
9/15 78/60/69/+4/0.00/…/.. 23 SE VEC1 23 SE RMY 25
9/16 83/55/69/+5/0.00/…/.. 22 SSW VEC1 21 SSW RMY 21
9/17 The low since midnight is 55F, the daily normal low is 55F.
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SEPTEMBER DAILY RECORDS TO DATE
NONE.
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DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR SEPTEMBER 17
HIGH 87F IN 2015
LOW 38F IN 1959
PRECIP 2.73 INCHES IN 1933
PEAK GUST 60 MPH WNW IN 1999
RECORDS FOR SEPTEMBER 18
HIGH 88F IN 1906
LOW 36F IN 1919
PRECIP 4.25 INCHES IN 1996
PEAK GUST 77e MPH WNW IN 1948
TODAY’S REPORT PREPARED BY: Matt Douglas
