Friday, September 22, 2023

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

FRIDAY, SEPTEMBER 22, 2023
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0531E
SUNSET:  1742E

MORE ABUNDANT SUNSHINE, INCREASING CLOUDS AND A BREEZY AFTERNOON…

Today has been another overall pleasant day on the hill. This morning
we had near calm conditions with temperatures in the low 60’s and
finished this afternoon with an increase of winds from the east and
just topping out at 68F. Although the dew points have slightly risen
since yesterday, it has still been a pleasant day for being outdoors,
especially with the afternoon sea breeze.

Temperatures remain about average for this time of year as well as for
the week. We started a bit warmer this morning and the dew points have
edged up into the upper 50’s.

The wind has been light for most of the day but has picked up quite a
bit this afternoon. The average so far today is only about 6 mph, with
winds from the E and ENE directions, and our peak gust came in after
1pm at about 21 mph.

Visibility started off at only 30 miles this morning due to a smoke
layer along the horizon, but lifted by afternoon and we finished with
about 50 miles of visibility by the last observation.

The maximum temperature so far today has been 68F, which is 2 degrees
below the normal high of 70F. The minimum temperature since midnight is
57F, which is 4 degrees above the normal low of 53F.

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Today’s Observations:

7 A.M.
Weather: Clear, few altocumulus/altocumulus castellanus NNE-E, few
cirrus all quadrants
Temperature: 60F; Dew Point: 58F; Relative Humidity: 93%
Wind: E @ 6 kts, wind light
Sea-level pressure: 1024.9 mb; 30.27 in. Hg: rising, then more
slowly
Visibility: 30 miles, thin smoke layer along the horizon all quadrants
6-hr Max temp: 60F
6-hr Min temp: 57F
24-hr Precip: 0.00 inches
BHO SA 1155 CLR 30 306/60/58/0806/043/ FEW AC/ACC NNE-E FEW CI ALQDS
THN K LYR ALG HRZN ALQDS WND LGT/ 8/081 51010 10060 20057

10 A.M.
Weather: Broken cumulus
Temperature: 66F; Dew Point: 57F; Relative Humidity: 70%
Wind: E @ 6 kts, wind light
Sea-level pressure: 1025.7 mb; 30.29 in. Hg: rising, then falling
Visibility: 40 miles
3-hr Precip: 0.00 inches
BHO SA 1455 E55 BKN 250 -BKN 40 316/66/57/1006/046/ FEW CU ALQDS
WND LGT/ 8/271 50010

1 P.M.
Weather: Clear, few cumulus SE-SW-N, few cirrus all quadrants
Temperature: 66F; Dew Point: 47F; Relative Humidity: 50%
Wind: E @ 7 kts
Sea-level pressure: 1031.1 mb; 30.45 in. Hg: falling steadily
Visibility: 50 miles
6-hr Max temp: 68F
6-hr Min temp: 60F
6-hr Precip: 0.00 inches
BHO SA 1755 CLR 50 311/66/47/1007/045/ FEW CU SE-SW-N FEW CI ALQDS/
8/201 57005 10068 20060

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SUMMARY FOR THURSDAY, SEPTEMBER 21, 2023

TEMPERATURE (DEGREES F)
MAX…….71   NORMAL…..71
MIN…….52   NORMAL…..54
MEAN……62   NORMAL…..62

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL………..0
TOTAL DEPARTURE FOR THE MONTH…………………+80 [+3.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2023 THRU JUN 2024)
TOTAL HEATING UNITS FOR YESTERDAY…………….3  DEPARTURE……..-1
TOTAL HEATING UNITS FOR THE MONTH……………21  DEPARTURE…….-26
TOTAL HEATING UNITS FOR THE SEASON…………..22  DEPARTURE…….-43
TOTAL HEATING UNITS LAST SEASON TO DATE………36  DEPARTURE…….-14

COOLING DEGREE DAYS (SEASON: JAN 2023 THRU DEC 2023)
TOTAL COOLING UNITS FOR YESTERDAY…………….0  DEPARTURE……..-2
TOTAL COOLING UNITS FOR THE MONTH…………..119  DEPARTURE…….+54
TOTAL COOLING UNITS FOR THE SEASON………….689  DEPARTURE…….+28
TOTAL COOLING UNITS LAST SEASON TO DATE……..884  DEPARTURE……-195

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)……….E17 NNW  @  05:03 A.M.
VECTOR #1 (1-Sec)……….17 NNW  @  04:00 A.M.
VECTOR #2 (1-Sec)……….16 NNW  @  04:03 A.M.
DAVIS #1……………….17 NNW  @  04:03 A.M.
DAVIS #2 ………………15 N    @  04:04 A.M.
RMY #1 (Instantaneous)…..17 NNW  @  04:06 A.M.
RMY #2 (Instantaneous)…..17 N    @  03:59 A.M.
MERLIN…………………13 NW
RICHARDS (C5C) (Inst)……17      @  04:06 A.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………13 NNW  @  04:33 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..13      @  04:25 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..13      @  04:34 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………13 NNW  @  04:04 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………13 N    @  04:02 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..13 NNW  @  04:04 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..13 NNW  @  04:38 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………13      @  04:04 A.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………6.6 NNW [158 total miles] VECTOR #1……………….7.1
VECTOR #2……………….7.4
DAVIS #1………………..7.0 N
DAVIS #2………………..6.6 NNE
RMY #1………………….7.1 N
RMY #2………………….7.3 NNE
RICHARDS (C5C)…………..7.5

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.15
TOTAL PRECIPITATION FOR THE MONTH…………..5.07 DEPARTURE…..+2.36
TOTAL PRECIPITATION FOR THE YEAR…………..45.52 DEPARTURE…..+8.20

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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   73/52/63/-6/0.00/774/98             23 SSW VEC1 22 SSW RMY 21
9/2   79/56/68/-1/0.00/708/90             25 SW  VEC1 24 SW  RMY 26
9/3   85/61/73/+5/T/674/86                21 SW  VEC1 21 SW  RMY 21
9/4   85/68/77/+9/0.00/719/92             17 NW  VEC1 16 NW  RMY 16
9/5   86/68/77/+9/0.00/647/83             16 NNE VEC1 16 ENE RMY 16
9/6   89/70/80/+12/0.00/722/93            17 WSW VEC1 17 SSW RMY 18
9/7   92/72/82/+15/0.00/726/94            20 SSW VEC1 21 SSW RMY 21
9/8   86/70/78/+11/0.00/293/38            30 SSW VEC1 31 SSW RMY 32 TSTM
9/9   86/68/77/+10/0.49/291/38            30 S   VEC1 31 S   RMY 29 TSTM
9/10  78/67/73/+7/0.25/008/01             17 NE  VEC1 17 NE  RMY 15 TSTM
9/11  74/67/71/+5/0.64/023/03             15 E   VEC1 15 E   RMY 14 TSTM
9/12  79/65/72/+6/T/250/33                18 E   VEC1 17 E   RMY 18
9/13  76/64/70/+5/1.92/242/32             35 SSW VEC1 35 SSW RMY 36 TSTM
9/14  75/57/66/+1/0.00/670/89             24 NW  VEC1 24 NW  RMY 24
9/15  66/53/60/-5/0.00/465/62             36 N   VEC1 35 N   RMY 35
9/16  68/54/61/-3/0.21/022/03             44 WNW VEC1 44 WNW RMY 47
9/17  76/53/65/+1/0.00/685/92             26 WNW VEC1 25 WNW RMY 24
9/18  64/60/62/-1/1.56/000/00             33 WNW VEC1 33 WNW RMY 35 TSTM
9/19  70/56/63/0/0.00/…/..              35 WNW VEC1 37 WNW RMY 36
9/20  72/53/63/0/0.00/…/..              21 WNW VEC1 21 WNW RMY 22
9/21  71/52/62/0/0.00/…/..              17 NNW VEC1 17 NNW RMY 17

9/22 The low since midnight is 57F, the daily normal low is 54F

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SEPTEMBER DAILY RECORDS

09/07/2023: NEW RECORD HIGH DAILY MINIMUM TEMPERATURE OF 72F;
BEATS THE RECORD OF 70F SET IN 1999

09/07/2023: RECORD HIGH TEMPERATURE OF 92F;
TIES THE RECORD OF 92F SET IN 2007 AND 2015

09/08/2023: RECORD HIGH DAILY MINIMUM TEMPERATURE OF 70F;
TIES THE RECORD OF 70F SET IN 2015

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

RECORDS FOR SEPTEMBER 22
HIGH 90F IN 1895, 1914
LOW 30F IN 1904 (Earliest freeze)
PRECIP 1.16 INCHES IN 2001
PEAK GUST 60 MPH SSW IN 1989

RECORDS FOR SEPTEMBER 23
HIGH 93F IN 1895,1914
LOW 33F IN 1904
PRECIP 2.67 INCHES IN 1994
PEAK GUST 62 MPH SSW IN 1989

TODAY’S REPORT PREPARED BY: Amanda Joly