Saturday, February 4, 2023

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

SATURDAY, FEBRUARY 4, 2023
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0655E
SUNSET:  1702E

AN ARCTIC BLAST BRINGS RECORD COLD AND DANGEROUS WIND CHILLS
TO BLUE HILL…

A brief, but brutal Arctic blast is impacting the region
with record low temperatures and dangerously cold wind
chills. Here at Blue Hill, we set two record low temperature
readings for both yesterday and today.

With the temperature at midnight reaching -11F, this set
a new record low for yesterday. This beat the previous
record low of -7F set in 1955!

The temperature continued to drop, reaching a minimum of
-13.9F (-14F) at around 3:45am this morning. This value
obliterated the previous record low for today of -4F set
back in 1886 and 1908!

Also, while likely not a record here on the hill (we
don’t have official dew point records available here),
the dew point looks to have dropped to as low as -29F
at around 4am this morning. True Arctic air for sure!

The wind chill at the 7am observation this morning was
a brutal -37F! We estimate that the minimum wind chill
overnight was between -40F and -45F.

Here is the current list of coldest temperatures ever
recorded here at Blue Hill, as compiled by our Chief
Scientist Mike Iacono.

BHO Coldest Minimum Temperatures, deg F (1885-2023):

1) -21 on 9 Feb 1934
2) -19 on 29 Dec 1933
3) -18 on 30 Dec 1933
-18 on 15 Feb 1943
5) -17 on 30 Dec 1917
6) -16 on 17 Feb 1896
-16 on 20 Dec 1942
-16 on 16 Feb 1943
-16 on 15 Jan 1957
10) -15 on 12 Jan 1886
11) -14 on 6 Jan 1896
-14 on 9 Dec 1902
-14 on 12 Feb 1914
-14 on 5 Feb 1918
-14 on 14 Feb 2016
-14 on 4 Feb 2023

Sunshine has been the theme today with temperatures so far
recovering to the upper single digits. The wind is still
busy, but not nearly as strong as it was overnight. As such
wind chill values have “warmed” to the single digits below
zero.

The high so far today of 9F degrees, which is 26 degrees
below the normal maximum of 35F. The low since midnight is
-14F degrees, which is 32 degrees below the normal minimum
of 18F.

————————————————————–

PRELIMINARY STATS FOR JANUARY 2023

TEMPERATURE, Deg. F
Avg. Max. 41.6 [ +6.9] Avg. Min. 29.1 [+10.8] Mean      35.4 [ +8.9] 24-hour corrected mean: 35.0
Max. for month: 55F on the 13th
Min. for month: 18F on the 11th

HEATING DEGREE DAYS
Total heating units:    913 [-280] Total for the season:  2823 [-580] Total for last season: 3141

COOLING DEGREE DAYS
Total cooling units:      0 [ 000] Total for the season:     0 [ 000] Total for last season:  889

PRECIPITATION, Inches
Total: 6.79 [+2.29] Greatest in 24 hrs: 1.32 on the 22-23rd

SNOWFALL, Inches
Total: 12.2 [-6.4] Greatest in 24 hrs: 4.1 on the 23rd

WIND, mph
Avg. uncorrected wind speed: 10.9 mph
Avg. corrected wind speed:   11.4 mph
Prevailing wind direction:   North [17%] Peak gust and direction:  54 SSE on the 13th

SUNSHINE:
Campbell-Stokes card minutes: 4392 of a possible 17130, or 26%
Astronomical total minutes: 4528 of a possible 17657, or 26%

————————————————————–

Today’s Observations:

7 A.M.
Weather: Clear, few stratocumulus offshore distant NNE-SE-SSW,
wind chill -37F
Temperature: -13F; Dew Point: -28F; Relative Humidity: 46%
Wind: NW @ 14G24 kts
Sea-level pressure: 1032.0 mb; 30.48 in. Hg: rising, then more rapidly
Visibility: 60 miles
6-hr Max temp: -12F
6-hr Min temp: -14F
24-hr Precip:  0.00 ins.
24-hr Snowfall: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1155 CLR 60 320/-13/-28/3114G24/048/ FEW SC OFFSHR DSNT
NNE-SE-SSW ARCTIC SEA SMOKE DSNT NE-ENE WCI -37/ 8/500 53024
11012 21014

10 A.M.
Weather: Clear, few stratocumulus offshore distant NNE-SE,
wind chill -25F
Temperature: -4F; Dew Point: -24F; Relative Humidity: 35%
Wind: WNW @ 14G20 kts, peak wind WNW 31mph at 9:14 A.M.
Sea-level pressure: 1034.1 mb; 30.54 in. Hg: rising, then more rapidly
Visibility: 70 miles
3-hr Precip:  0.00 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1455 CLR 70 341/-4/-24/2914G20/054/ FEW SC OFFSHR DSNT NNE-SE
PK WND 3027/14/ WCI -25/ 8/500 53021

1 P.M.
Weather: Scattered cirrus, few stratocumulus offshore distant
NE-ESE
Temperature: 8F; Dew Point: -20F; Relative Humidity: 25%
Wind: WNW @ 10G17 kts
Sea-level pressure: 1033.4 mb; 30.52 in. Hg: rising, then falling
Visibility: 80 miles
6-hr Max temp: 8F
6-hr Min temp: -13F
6-hr Precip:  0.00 ins.
6-hr Snowfall: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1755 250 SCT 80 334/8/-20/2910G17/052/ FEW SC OFFSHR DSNT
NE-ESE/ 8/504 58007 10008 21013

————————————————————–

SUMMARY FOR FRIDAY, FEBRUARY 3, 2023

TEMPERATURE (DEGREES F)
MAX…….28   NORMAL…..35
MIN……-11R  NORMAL…..18
MEAN…….9   NORMAL…..26

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……..-17
TOTAL DEPARTURE FOR THE MONTH………………..-16 [-5.5 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2022 THRU JUN 2023)
TOTAL HEATING UNITS FOR YESTERDAY……………56  DEPARTURE…….+17
TOTAL HEATING UNITS FOR THE MONTH…………..133  DEPARTURE…….+17
TOTAL HEATING UNITS FOR THE SEASON…………2956  DEPARTURE……-564
TOTAL HEATING UNITS LAST SEASON TO DATE…….3232  DEPARTURE……-276

PEAK WIND GUST (MPH):
420C (Official)…………56 WNW @  7:33 P.M.
VECTOR #2 (1-Sec)……….61     @  7:33 P.M.
DAVIS #1……………….56 W   @  6:18 P.M.
DAVIS #2 ………………57 WNW @  7:33 P.M.
RMY #2 (Instantaneous)…..64 WNW @  7:25 P.M.
MERLIN…………………52 WNW
VECTOR #1……OUT OF SERVICE D/T RENOVATIONS
RMY #1………OUT OF SERVICE D/T RENOVATIONS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………43 WNW @  7:34 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..42     @  7:34 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………41 W   @  7:22 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………43 WNW @  7:34 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..42 WNW @  7:34 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE RMY #1 AVERAGE……OUT OF SERVICE D/T RENOVATIONS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……23.5 WNW [563 total miles] VECTOR #2…………….23.4
DAVIS #1……………..22.3 WNW
DAVIS #2……………..23.7 NW
RMY #2……………….23.1 WNW
RMY #1……….OUT OF SERVICE D/T RENOVATIONS
VECTOR #1…….OUT OF SERVICE D/T RENOVATIONS
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.13
TOTAL PRECIPITATION FOR THE MONTH………….TRACE DEPARTURE…..-0.41
TOTAL PRECIPITATION FOR THE YEAR……………6.79 DEPARTURE…..+1.88

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE……-0.6
TOTAL SNOWFALL FOR THE MONTH………………TRACE DEPARTURE……-2.0
TOTAL SNOWFALL FOR THE SEASON (2022-2023)……14.9 DEPARTURE…..-20.8

————————————————————–

PRELIMINARY CLIMATE SUMMARY FOR JANUARY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN)/SUN(%)/PEAK GUST/VEC1/RMY GUST
VEC1: Vector #1 1-second gust
RMY:  R.M. Young wind gust recording system (Instantaneous)
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized
M:    Missing data

1/1   53/38/46/+17/0.04/0.0/412/75        39 WNW  VEC1 N/A    RMY 60
1/2   49/33/41/+13/0.00/0.0/044/08        39 WNW  VEC1 N/A    RMY 39
1/3   48/37/43/+15/0.50/0.0/000/00        23 S    VEC1 N/A    RMY 24
1/4   43/37/40/+12/0.31/0.0/000/00        23 NE   VEC1 N/A    RMY 23
1/5   43/33/38/+10/0.23/0.0/000/00        34 ENE  VEC1 N/A    RMY 37
1/6   35/31/33/+5/0.18/1.0/000/00         19 NNE  VEC1 N/A    RMY 19
1/7   40/30/35/+8/0.00/0.0/105/19         22 NW   VEC1 N/A    RMY 23
1/8   36/20/28/+1/0.00/0.0/517/93         26 NNW  VEC1 N/A    RMY 28
1/9   42/26/34/+7/T/0.1/267/48            27 NW   VEC1 N/A    RMY 27
1/10  41/25/33/6/0.00/0.0/318/57          28 NW   VEC1 N/A    RMY 28
1/11  33/18/26/-1/T/0.1/358/64            19 N    VEC1 N/A    RMY 18
1/12  48/28/38/+11/0.29/0.1/000/00        45 S    VEC1 N/A    RMY 46
1/13  55/36/46/+20/0.62/0.0/000/00        54 SSW  VEC1 N/A    RMY 56
1/14  36/29/33/+7/0.11/T/000/00           30 NNE  VEC1 N/A    RMY M
1/15  33/26/30/+4/0.10/1.2/000/00         45 NNE  VEC1 N/A    RMY 45
1/16  30/26/28/+2/0.22/2.7/000/00         36 NNE  VEC1 N/A    RMY 37
1/17  47/25/36/+10/0.02/0.0/415/73        22 WSW  VEC1 N/A    RMY 23
1/18  49/35/42/+16/0.01/0.0/314/55        37 NW   VEC1 N/A    RMY 38
1/19  38/32/35/+9/0.75/T/000/00           31 NNE  VEC1 N/A    RMY 32
1/20  35/29/32/+6/0.56/1.6/000/00         52 NE   VEC1 N/A    RMY 54
1/21  31/25/28/+2/0.01/0.2/000/00         21 NW   VEC1 N/A    RMY 21
1/22  35/25/30/+4/0.25/0.2/000/00         21 N    VEC1 N/A    RMY 20
1/23  34/27/31/+5/1.18/4.1/000/00         36 NNW  VEC1 N/A    RMY 37
1/24  35/25/20/+4/0.00/0.0/157/27         32 WNW  VEC1 N/A    RMY 32
1/25  42/27/35/+9/0.45/0.1/012/02         40 SSE  VEC1 N/A    RMY 42
1/26  53/33/43/+17/0.85/T/029/05          52 S    VEC1 N/A    RMY 54
1/27  41/25/33/+7/0.00/0.0/577/98         31 WNW  VEC1 N/A    RMY 29
1/28  48/29/39/+13/0.00/0.0/390/66        38 W    VEC1 N/A    RMY 40
1/29  49/36/43/+17/T/0.0/101/17           33 S    VEC1 N/A    RMY 38
1/30  50/36/43/+17/0.00/0.0/327/55        18 SW   VEC1 N/A    RMY 20
1/31  39/21/30/+4/0.11/0.8/185/31         28 NW   VEC1 N/A    RMY 29

PRELIMINARY CLIMATE SUMMARY FOR FEBRUARY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN)/SUN(%)/PEAK GUST/VEC1/RMY GUST
VEC1: Vector #1 1-second gust
RMY:  R.M. Young wind gust recording system (Instantaneous)
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized
M:    Missing data

2/1   30/18/24/-2/T/T/…/..              17 NW   VEC1 N/A    RMY 20
2/2   38/19/29/+3/0.00/0.0/…/..         25 SW   VEC1 N/A    RMY 29
2/3   28/-11/9/-17/T/T/…/..             56 WNW  VEC1 N/A    RMY 64

2/4 The low since midnight is -14F, the daily normal low is 18F

DAILY RECORDS

02/03/2023: NEW RECORD MINIMUM TEMPERATURE OF -11F,
THIS BEATS THE OLD RECORD OF -7F SET IN 1955

02/04/2023: NEW RECORD MINIMUM TEMPERATURE OF -14F,
THIS BEATS THE OLD RECORD OF -4F SET IN 1886 AND 1908

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

RECORDS FOR FEBRUARY 4
HIGH 63F IN 1991
LOW -4F IN 1886, 1908
PRECIP 1.80 INS. IN 1926
SNOWFALL 15.0 INS. IN 1961
PEAK GUST 89 MPH SSE IN 1972

RECORDS FOR FEBRUARY 5
HIGH 65F IN 1991
LOW -14F IN 1918
PRECIP 1.62 INS. IN 2016
SNOWFALL 16.0 INS. IN 1907
PEAK GUST 67 MPH WNW IN 1969

TODAY’S REPORT PREPARED BY: Matt Douglas