Friday, January 7, 2022

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

FRIDAY, JANUARY 7, 2022
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0713E
SUNSET:  1628E

FIRST SIGNIFICANT SNOWFALL OF THE SEASON ATOP GREAT BLUE HILL…

A quick hitting low pressure system slid southeast of Nantucket this
morning delivering a solid thump of snow…so much so that this
observer was forced to abandon his car at the base and hike up the
hill for the 7AM observation!

What was initially expected to be a 4-8″ event translated
into a 15.2″ event total! After melting down the snow to liquid form
in our gauge, we recorded a snow water equivalent (SWE) of 0.74″. Do
some quick math and that is an average snow ratio of 21:1!

So, what allowed for such considerable accumulation in about a 6-hour
window? First, from the wee hours of the morning to about 10AM, we were
caught under deformation-induced frontogenesis (in other words, a
quasi-stationary axis of heavy snowfall rates of 1-3″ per hour away
from the center of low pressure). Second, cold air aloft provided good
dendrite development. And third, winds were rather light. The peak gust
during the storm was “just” 28 MPH…for intense snows, this is rather
unusual. As such, these low winds actually allowed dendrites to avoid
significant collision and compaction before reaching the surface, thus
maintaining their large shape.

Temps hovered in the mid to upper 20s during snowfall, so a powdery
snow has made for an easier cleanup.

The high so far today is 28F, which is 7  degrees below the
normal high of 35F. The low since midnight is 26F, which is
7 degrees above the normal low of 19F.

————————————————————–

PRELIMINARY STATS FOR DECEMBER 2021

TEMPERATURE, Deg. F
Avg. Max. 43.0 [+2.8] Avg. Min. 29.7 [+2.8] Mean      36.4 [+3.9] 24-hour corrected mean: 36.2
Max. for month: 62F on the 11th
Min. for month: 15F on the 20th

HEATING DEGREE DAYS
Total heating units:    879 [-127] Total for the season:  1886 [-324] Total for last season: 2210

PRECIPITATION, Inches
Total: 2.63 [-2.76] Greatest in 24 hrs: 1.00 inch on the 12th

SNOWFALL, Inches
Total: 1.7 ins. [-10.3] Greatest in 24 hrs: 1.2 ins. from the 8th-9th

WIND, mph
Avg. uncorrected wind speed: 11.6 mph
Avg. corrected wind speed:   12.1 mph
Prevailing wind direction:   WNW [14%] Peak gust and direction:     59 WNW on the 6th

SUNSHINE:
Campbell-Stokes card minutes: 5790 minutes of a possible 16470 or 35%
Astronomical total minutes: 5973 minutes of a possible 17037 or 35%

————————————————————–

Today’s Observations:

7 A.M.
Weather: Heavy Snow & Fog, Sky Obscured, Vertical Visibility 300 ft.
Temperature: 28F; Dew Point: 27F; Relative Humidity: 98%
Wind: N @ 10G13 kts
Sea-level pressure: 1004.7 mb; 29.67 in. Hg: falling, then falling less rapidly
Visibility: 1/8 mile
6-hr Max temp: 28F
6-hr Min temp: 26F
24-hr Precip:  0.38 ins.
24-hr Snowfall: 9.7 ins.
Snow Depth: 10 ins.
BHO SA 1155 X W3 1/8S+F 047/28/27/3510G13/967/ TOTAL NEW SNW PST 24 HRS
9.7 INS/ 8//// 4/010 56055 6038/ 70038 10028 20026

10 A.M.
Weather: Moderate Snow & Fog, Sky Obscured, Vertical Visibility 300 ft.
Temperature: 27F; Dew Point: 26F; Relative Humidity: 98%
Wind: NNW @ 14G23 kts
Sea-level pressure: 1002.8mb; 29.61 in Hg; falling, then falling less rapidly
Visibility: 1/8 mile
3-hr Precip:  0.26 ins.
3-hr Snowfall: 4.5 ins.
BHO SA 1455 X W3 1/8SF 028/27/26/3314G23/961/ TOTAL NEW SNW PST 3 HRS
4.5 INS/ 8//// 56019 6026/

1 P.M.
Weather: Light Snow & Fog, Overcast Stratus
Temperature: 27F, Dew point: 25F; Relative Humidity: 93%
Wind: NNW at 13G23 kts
Sea-level pressure: 1003.2 mb; 29.62 in Hg; rising unsteadily
Visibility: 1 mile
6-hr Max temp: 28F
6-hr Min temp: 26F
6-hr Precip:  0.36 ins.
6-hr Snowfall: 5.5 ins.
Snow Depth: 13 ins.
BHO SA 1755 15 OVC 1S-F 032/27/25/3313G23/962/ TOTAL NEW SNW PST
6 HRS 5.5 INS STORM TOTAL 15.2 INS/ 8//// 4/013 52004 6036/ 10028
20026

SUMMARY FOR THURSDAY, JANUARY 6, 2022

TEMPERATURE (DEGREES F)
MAX…….40     NORMAL…..35
MIN…….27     NORMAL…..20
MEAN……34     NORMAL…..28

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……………. +6
TOTAL DEPARTURE FOR THE MONTH……………………….+33 [+5.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2021 THRU JUN 2022)
TOTAL HEATING UNITS FOR YESTERDAY……………31  DEPARTURE……. -7
TOTAL HEATING UNITS FOR THE MONTH…………..188  DEPARTURE…….-34
TOTAL HEATING UNITS FOR THE SEASON…………2074  DEPARTURE……-358
TOTAL HEATING UNITS LAST SEASON TO DATE…….2126  DEPARTURE…….-52

PEAK WIND GUST (MPH):
Official (1-Sec AVG)…….36 WNW @ 12:06 P.M.
AEROVANE……………….36 WNW @ 12:06 P.M.
VECTOR #2 (Instantaneous)..39     @ 12:15 P.M.
DAVIS #2 ………………34 W   @ 12:06 P.M.
RMY #2 (Instantaneous)…..36 WNW @ 12:15 P.M.
ASOS………..OUT OF SERVICE D/T RENOVATIONS
VECTOR #1……OUT OF SERVICE D/T RENOVATIONS
DAVIS #1…….OUT OF SERVICE D/T RENOVATIONS
RMY #1………OUT OF SERVICE D/T RENOVATIONS
MERLIN………OUT OF SERVICE D/T RENOVATIONS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………26 WNW @ 12:12 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..27     @ 12:08 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………26 WNW @ 12:08 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..26 WNW @ 12:08 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE…….OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE…OUT OF SERVICE D/T RENOVATIONS
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……10.5 WNW [252 total miles] VECTOR #2…………….11.8
DAVIS #2……………..11.7 WNW
RMY #2……………….11.7 WNW
RMY #1…………..OUT OF SERVICE D/T RENOVATIONS
ASOS…………….OUT OF SERVICE D/T RENOVATIONS
VECTOR #1………..OUT OF SERVICE D/T RENOVATIONS
DAVIS #1…………OUT OF SERVICE D/T RENOVATIONS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.38  DEPARTURE…..+0.23
TOTAL PRECIPITATION FOR THE MONTH………….0.96  DEPARTURE…..+0.04
TOTAL PRECIPITATION FOR THE YEAR…………. 0.96  DEPARTURE…..+0.04

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M………….9.7  DEPARTURE……+9.1
TOTAL SNOWFALL FOR THE MONTH……………….9.7  DEPARTURE……+6.5
TOTAL SNOWFALL FOR THE SEASON (2021-2022)…..12.4  DEPARTURE……-5.9

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

12/01   44/30/37/0.00/0.0/263/47          35 W   AERO 35 W   RMY 34
12/02   58/35/47/10/T/0.0/106/19          56 WNW AERO 59 WNW RMY 62 TSTM
12/03   41/28/35/-1/0.00/0.0/512/92       46 NW  AERO 44 NW  RMY 46
12/04   39/25/32/-4/0.00/0.0/233/42       25 SW  AERO 23 SW  RMY 26
12/05   45/32/39/+3/0.00/0.0/460/83       25 SE  AERO 25 SE  RMY 25
12/06   59/37/48/+13/0.34/0.0/077/14      59 WNW AERO 59 NW  RMY 60
12/07   40/29/35/0/T/0.0/436/79           47 WNW AERO 36 WNW RMY 48
12/08   34/25/30/-5/0.05/0.6/000/00       26 NNE AERO 25 NE  RMY 26
12/09   35/20/28/-6/0.05/0.6/319/58       32 NW  AERO 30 NW  RMY 33
12/10   43/27/35/+1/0.00/0.0/000/00       21 SE  AERO 20 SE  RMY 21
12/11   62/37/50/+16/0.34/0.0/000/00      57 SSW AERO 59 SSW RMY 58
12/12   58/36/47/+13/0.05/0.0/416/76      55 WNW AERO 55 WNW RMY 58
12/13   50/35/43/+10/0.00/0.0/224/41      32 WSW AERO 33 WSW RMY 33
12/14   50/33/42/+9/0.00/0.0/442/81       31 WSW AERO 30 WSW RMY 32
12/15   42/28/35/+2/T/0.0/153/28          35 SSE AERO 35 SSE RMY 36
12/16   58/42/50/+18/0.21/0.0/016/03      35 SW  AERO 37 SW  RMY 38
12/17   56/39/48/+16/0.00/0.0/518/95      43 WNW AERO 41 WNW RMY 46
12/18   39/31/35/+3/0.52/0.2/000/00       21 NNW AERO 20 NNW RMY 20
12/19   39/20/30/-2/0.39/0.0/082/15       35 NNW AERO 37 NNW RMY 36
12/20   32/15/24/-7/0.00/0.0/528/97       29 SSW AERO 30 SSW RMY 30
12/21   40/27/34/+3/0.00/0.0/371/68       31 SW  AERO 32 SW  RMY 33
12/22   45/30/38/+7/0.10/0.0/038/07       47 NW  AERO 45 NW  RMY 47
12/23   30/21/26/-5/0.00/0.0/441/81       39 NW  AERO 38 NW  RMY 37
12/24   25/20/23/-7/0.01/0.1/000/00       14 N   AERO 13 N   RMY 14
12/25   34/25/30/0/0.34/0.0/000/00        20 NNW AERO 20 NNW RMY 18
12/26   37/30/34/+4/0.09/T/120/22         37 NW  AERO 37 NW  RMY 37
12/27   33/26/30/0/T/T/071/13             32 NW  AERO 35 NW  RMY 35
12/28   42/30/36/+7/0.06/0.1/147/27       34 NW  AERO 32 NW  RMY 35
12/29   40/32/36/+7/0.01/0.1/000/00         13 WSW AERO 12 WSW RMY 13
12/30   39/36/38/+9/0.04/0.0/000/00       11 N   AERO 13 SE  RMY 11
12/31   43/39/41/+12/0.03/0.0/000/00      17 S   AERO 16 S   RMY 18

DAILY RECORDS FOR DECEMBER 2021

12/16/21: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 42F
TIES PREVIOUS RECORD OF 42F SET IN 1982

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

1/1   51/43/47/+18/0.08/0.0/000/00        21 SSE AERO 21 SSE RMY 22
1/2   48/29/39/+11/0.29/0.0/000/00        35 NW  AERO 36 NW  RMY 35
1/3   29/18/24/-4/0.00/0.0/000/00         31 NNW AERO 30 N   RMY 30
1/4   30/12/21/-7/0.00/0.0/…/..         25 S   AERO 24 S   RMY 25
1/5   49/25/37/+9/…./0.0/…/..         45 S   AERO 48 S   RMY 47
1/6   40/27/34/+6/0.00/0.0/…/..         36 WNW AERO 36 WNW RMY 36

1/7  The low since midnight is 26F, the daily normal low is 19F

DAILY RECORDS FOR JANUARY 2022

1/1/22: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 43F
SURPASSES PREVIOUS RECORD OF 42F SET IN 1966

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

RECORDS FOR JANUARY 7
HIGH 60F IN 1930
LOW -8F IN 2018
PRECIP 1.97 INS. IN 1977
SNOWFALL 16.0 INS. IN 1977
PEAK GUST 74 MPH NW IN 1968

RECORDS FOR JANUARY 8
HIGH 65F IN 2008
LOW -8F IN 1968
PRECIP 1.70 INS. IN 1958, 1979
SNOWFALL 12.5 INS. IN 1996
PEAK GUST 77 MPH NNW IN 1958

TODAY’S REPORT PREPARED BY: Andrew Swanson