Saturday, September 21, 2024

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

SATURDAY, SEPTEMBER 21, 2024
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0531E
SUNSET:  1742E

LIGHT RAIN WITH A BREEZE AGAIN TODAY…

The rain and wind have continued today as a coastal low remains parked
offshore. For the 24-hour period ending at 7am this morning, we
received 0.20″, with an additional 0.48″ falling through 1pm.
The intensity has mostly been light, though moderate at times.

The temperature has barely budged today, falling slightly overnight
from the upper 50s to the mid 50s, but then holding steady at 56F since.
With the rain it is a bit chilly out there!

Winds have remained steady, with frequent gusts in the 20-25mph range.
The flow is mostly out of the north-northeast to this point. Our peak gust
so far occurred a bit after 9am this morning, with a value of 30mph.

Visibility has been poor today due to the low clouds and fog, ranging
from 1/2-2 miles.

The maximum temperature so far today is 58F, which is 13 degrees below
the normal high of 71F. The minimum temperature since midnight is 56F,
which is 2 degrees above the normal low of 54F.

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Today’s Observations:

7 A.M.
Weather: Light rain and fog, sky obscured, vertical visibility 200ft
Temperature: 56F; Dew Point: 56F; Relative Humidity: 100%
Wind: N @ 12G20 kts
Sea-level pressure: 1017.1 mb; 30.03 in. Hg: rising unsteadily
Visibility: 1 mile, fog
6-hr Max temp: 58F
6-hr Min temp: 56F
24-hr Precip:  0.20 inches
BHO SA 1155 X W2 1R-F 171/56/56/0112G20/003/ 8//// 52013 70020
10058 20056

10 A.M.
Weather: Light rain and fog, overcast stratus,
few lower stratus fractus all quadrants
Temperature: 56F; Dew Point: 56F; Relative Humidity: 100%
Wind: NNE @ 13G22 kts, peak wind N 30mph at 9:15 A.M.
Sea-level pressure: 1017.4 mb; 30.04 in. Hg: rising, then falling
Visibility: 2 miles, fog
3-hr Precip: 0.25 inches
BHO SA 1455 E4 OVC 2R-F 174/56/56/0213G22/004/ FEW LWR STFRA ALQDS
PK WND 0126/15/ 8/6// 50003 6025/

1 P.M.
Weather: Light rain and fog, sky obscured, vertical visibility 200ft
Temperature: 56F; Dew Point: 56F; Relative Humidity: 100%
Wind: NNE @ 13G22 kts
Sea-level pressure: 1017.0 mb; 30.03 in. Hg: falling unsteadily
Visibility: 1/2 mile, fog
6-hr Max temp: 56F
6-hr Min temp: 56F
6-hr Precip: 0.48 inches
BHO SA 1755 X W2 1/2R-F 170/56/56/0213G22/003/ 8//// 57004 6048/
10056 20056

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SUMMARY FOR FRIDAY, SEPTEMBER 20, 2024

TEMPERATURE (DEGREES F)
MAX…….63  NORMAL…..71
MIN…….58  NORMAL…..54
MEAN……61  NORMAL…..63

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………..-2
TOTAL DEPARTURE FOR THE MONTH…………………….+24 [+1.0 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY…………….4  DEPARTURE………0
TOTAL HEATING UNITS FOR THE MONTH……………14  DEPARTURE…….-29
TOTAL HEATING UNITS FOR THE SEASON…………..25  DEPARTURE…….-36
TOTAL HEATING UNITS LAST SEASON TO DATE………19  DEPARTURE……..+6

COOLING DEGREE DAYS (SEASON: JAN 2024 THRU DEC 2024)
TOTAL COOLING UNITS FOR YESTERDAY…………….0  DEPARTURE……..-2
TOTAL COOLING UNITS FOR THE MONTH……………59  DEPARTURE……..-4
TOTAL COOLING UNITS FOR THE SEASON………….753  DEPARTURE…….+94
TOTAL COOLING UNITS LAST SEASON TO DATE……..689  DEPARTURE…….+64

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)……….E38 NE   @   10:14 P.M.
VECTOR #1 (1-Sec)……….38 NE   @   10:14 P.M.
VECTOR #2 (1-Sec)……….37 NE   @   10:13 P.M.
DAVIS #1……………….33 NE   @   10:14 P.M.
DAVIS #2 ………………34 ENE  @   09:09 A.M.
RMY #1 (Instantaneous)…..40 NE   @   10:14 P.M.
RMY #2 (Instantaneous)…..41 NE   @   09:16 A.M.
MERLIN…………………35 NE
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………23 NE   @   09:20 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..22      @   09:09 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..23      @   09:09 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………23 NE   @   09:09 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………23 ENE  @   01:42 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..21 NE   @   01:42 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..22 NE   @   01:42 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…….14.4 NE [345 total miles] VECTOR #1……………..13.8
VECTOR #2……………..14.5
DAVIS #1………………14.5 NE
DAVIS #2………………14.2 ENE
RMY #1………………..13.4 NE
RMY #2………………..14.1 NE
RICHARDS (C5C)………….OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.20 DEPARTURE…..+0.05
TOTAL PRECIPITATION FOR THE MONTH…………..0.37 DEPARTURE…..-2.19
TOTAL PRECIPITATION FOR THE YEAR (2024)…….41.58 DEPARTURE…..+4.41

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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/+4/0.00/711/94             20 S   VEC1 19 S   RMY 20
9/13  85/59/72/+7/0.00/595/79             21 SSW VEC1 20 SSW RMY 20
9/14  81/61/71/+6/0.00/691/92             21 ENE VEC1 20 ENE RMY 21
9/15  78/60/69/+4/0.00/598/80             23 SE  VEC1 23 SE  RMY 25
9/16  83/55/69/+5/0.00/700/94             22 SSW VEC1 21 SSW RMY 21
9/17  83/55/69/+5/0.00/453/61             16 SW  VEC1 14 S   RMY 15
9/18  77/60/69/+6/0.00/163/22             15 W   VEC1 14 W   RMY 14
9/19  69/60/65/+2/0.10/…/..             30 NE  VEC1 30 NE  RMY 31
9/20  63/58/61/-2/…/…/..              38 NE  VEC1 38 NE  RMY 40

9/21  The low since midnight is 56F, the daily normal low is 54F.

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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 21
HIGH 91 IN 1895
LOW 35 IN 1929, 1956, 1962
PRECIP 5.58 INS IN 1961 (HURRICANE ESTHER; RETURNED AS TS SEPT 25-26TH)
PEAK GUST 186 MPH S IN 1938 (GREAT NEW ENGLAND HURRICANE; CALCULATED GUST, STATION RECORD)

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

TODAY’S REPORT PREPARED BY: Joshua Polen