Thursday, January 11, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, JANUARY 11, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

ABOVE SEASONABLE TEMPERATURES CAUSES RAPID
SNOW MELT….

Wind from the south has brought above seasonable
temperatures today. Yesterday we were very close
to seasonable but temperatures began to rise last
night around 10:00 P.M. and have continued to rise
all day with a high so far of 49F. This 15 balmy
degrees above the daily normal of 34F. These warm
temperatures are causing the snow on ground to melt
rapidly leaving us with 7 ins. by 1:00 P.M. The wind
picked up and the sky became overcast this afternoon
as the pressure began to drop. Visibility was limited
to 35 miles today due to a lingering distant fog.

Today’s Observations:

7 A.M.
Weather: Broken stratus, broken altocumulus
Temperature: 39F; Dew Point: 37F; Wind: SSW at 17G22 kts
Sea-level pressure: 30.37 ins. Hg, falling, then more quickly
Visibility: 40 miles, distant fog in all directions
6-hr Max temp: 32F
6-hr Min temp: 39F
24-hr precip: 0.00 ins.
24-hr snowfall: 0.00 ins.
Snow depth: 9 ins.
BHO SA 1155 E25 BKN 100 BKN 40 284/39/37/2117G22/037/
DSNT FG ALQDS/ 8/670 4/009 58006 10032 20039

10 A.M.
Weather: Broken stratus
Temperature: 44F; Dew Point: 41F; Wind: SSW at 16G22 kts
Sea-level pressure: 30.35 ins. Hg, rising unsteadily
Visibility: 35 miles, distant fog in all directions
3-hr precip: 0.00 ins.
3-hr snowfall: 0.00 ins.
BHO SA 1455 E8 BKN 35 276/44/41/2016G22/035/
DSNT FG ALQDS/ 8/600 51008

1 P.M.
Weather: Scattered stratus, overcast altostratus
break in overcast N-NNE, sun dimly visible
Temperature: 49F; Dew Point: 44F; Wind: SSW at 16G22 kts
Sea-level pressure: 30.29 ins. Hg, falling, then more quickly
Visibility: 35 miles, distant fog in all directions
6-hr Max temp: 49F
6-hr Min temp: 39F
6-hr precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
Snow depth: 7 ins.
BHO SA 1755 15 SCT E49 OVC 35 258/49/44/2016G22/029/ BINOVC N-NNE
SUN DMLY VSBL DSNT FG ALQDS/ 8/6/// 4/007 58018 10049 20039

PRELIMINARY STATS FOR DECEMBER 2017

TEMPERATURE, Deg. F
Avg. Max. 33.9 [-5.2] Avg. Min. 21.2 [-2.4] Mean 27.6 [-3.7] Corrected mean: 27.2
Max. for month: 58 on the 5TH
Min. for month: -3 on the 29TH

HEATING DEGREE DAYS
Total heating units: 1153 [+110] Total for the season: 2122 [-183] Total for last season: 2032

PRECIPITATION, Inches
Total: 3.08 [-1.81] Greatest in 24 hrs: 0.78 in. on the 22nd-23rd

SNOWFALL, Inches
Total: 9.3 [-4.1]

WIND, mph
Avg. uncorrected wind speed: 11.6
Avg. corrected wind speed: 12.0
Prevailing wind direction: W @ 23%
Peak gust and direction: 62 S on the 5th

SUNSHINE:
Astronomical total minutes: 7367 minutes of possible 16994 or 43%
Campbell-Stokes card minutes: 7140 minutes of possible 16470 or 43%

SUMMARY FOR WEDNESDAY, JANUARY 10, 2018

TEMPERATURE (DEGREES F)
MAX…..36 NORMAL…..34
MIN…..20 NORMAL…..17
MEAN….28 NORMAL…..25

DEPARTURE FROM 30-YEAR NORMAL………………………+3
TOTAL DEPARTURE FOR THE MONTH…………………….-106 [-10.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….37 DEPARTURE……….-3
TOTAL HEATING UNITS FOR THE MONTH…………495 DEPARTURE……..+106
TOTAL HEATING UNITS FOR THE SEASON……….2617 DEPARTURE………-76
TOTAL HEATING UNITS LAST SEASON TO DATE…..2414 DIFFERENCE…….+203

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….30 W AT 11:37 P.M.
AERO……………………30 W AT 11:38 P.M.
ASOS……………………32 SW AT 11:38 P.M.*
DAVIS…………………..N/A* RMY N/A
FASTEST MILE FOR YESTERDAY…………………23 W AT 11:59 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………23 SSW AT 11:57 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..N/A*
AVERAGE WIND SPEED AND DIRECTION…………..11.3 W
ASOS…………………..12.4*
DAVIS…………………..N/A*

*ASOS and Davis anemometers malfunctioning
** Last of several occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00 DEPARTURE……-0.14
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.68 DEPARTURE……+0.26
ASOS…………..1.98
TOTAL PRECIPITATION FOR THE YEAR………..1.68 DEPARTURE……+0.26
ASOS…………..1.98

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0 DEPARTURE……..-0.5
TOTAL SNOWFALL FOR THE MONTH……………16.5 DEPARTURE…….+10.9
TOTAL SNOWFALL FOR THE SEASON…………..25.8 DEPARTURE……..+4.2

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

1/01 11/-5/3/-24/0.00/0.0/…/.. 30 NW AERO 30 NW RMY 31
1/02 15/-2/7/-20/0.00/0.0/…/.. 26 W AERO 25 W RMY 26
1/03 28/11/20/-6/0.00/0.0/…/.. 23 WSW AERO 20 WSW RMY N/A
1/04 28/18/23/-3/1.66/16.5/000/00 54 NNW AERO 60 NNW RMY 64
1/05 18/2/10/-16/0.00/0.0/…/.. 53 W AERO 53 W RMY 57
1/06 10/-2/4/-22/0.00/0.0/…/.. 43 WSW AERO 47 WSW RMY 47
1/07 14/-8/3/23/0.00/0.0/…/.. 37 WNW AERO 35 WNW RMY N/A
1/08 33/14/24/T/T/…/.. 40 S AERO 40 S RMY 42
1/09 40/25/33/T/T/…/.. 37 W AERO 35 W RMY 33
1/10 36/20/28/0.00/0.0/…/.. 30 W AERO 30 W RMY N/A

1/11 Low temp since midnight is 32F; normal low is now 17F

DAILY RECORDS FOR JANUARY 2018

01/04/18: NEW DAILY RECORD MAXIMUM SNOWFALL OF 16.5 INS.
PREVIOUS RECORD WAS 8.6 INS. SET IN 1923 AND
TIED IN 1942

01/07/18: DAILY RECORD LOW MINIMUM TEMPERATURE OF -8F,
PREVIOUS RECORD OF -7F WAS SET IN 1896

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2017 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 50/35/43/+6/0.04/0.0/262/47 28 NW AERO 29 NW RMY 30
12/02 42/29/36/0/0.00/0.0/033/06 20 NNW AERO 18 NNW RMY N/A
12/03 42/32/37/+1/0.00/0.0/172/31 14 N AERO 10 N RMY N/A
12/04 43/32/38/+3/0.00/0.0/522/94 16 E AERO 14 E RMY N/A
12/05 58/34/46/+11/0.18/0.0/000/00 62 S AERO 66 S RMY 65
12/06 56/32/44/+9/0.54/0.0/160/29 52 S AERO 55 S RMY N/A
12/07 44/30/37/+3/0.00/0.0/540/98 25 WSW AERO 24 WSW RMY 25
12/08 38/28/33/-1/0.00/0.0/116/21 21 W AERO 18 W RMY 20
12/09 34/28/31/-3./0.70/5.5/000/00 23 NNW AERO 23 NNW RMY 23
12/10 35/27/31/-2/0.02/0.1/384/70 30 W AERO 30 W RMY 27
12/11 38/29/34/+1/0.00/0.0/301/55 23 W AERO 21 W RMY 22
12/12 43/31/37/+4/0.06/0.0/000/00 35 W AERO 31 W RMY N/A
12/13 31/18/25/-7/0.00/0.0/372/68 44 W AERO 44 W RMY 44
12/14 27/14/21/-11/T/T/257/47 35 WSW AERO 33 W RMY 34
12/15 24/12/18/-14/0.00/0.0/011/02 25 W AERO 23 W RMY N/A
12/16 32/17/25/-6/0.00/0.0/382/70 33 W AERO 35 W RMY 36
12/17 27/14/21/-10/0.00/0.0/425/78 21 NW AERO 21 NW RMY 20
12/18 35/20/28/-3/T/T/011/02 20 SSE AERO 16 SSE RMY 20
12/19 49/34/42/+12/0.00/0.0/185/34 36 WNW AERO 35 SW RMY 38
12/20 42/26/34/+4/T/0.0/447/82 41 W AERO 40 W RMY 45
12/21 32/23/28/-2/0.00/0.0/533/98 26 NW AERO 24 NW RMY 27
12/22 32/21/27/-2/0.08/T/000/00 18 E AERO 17 E RMY N/A
12/23 36/24/30/+1/0.70/T/000/00 31 WSW AERO 28 WSW RMY 31
12/24 35/29/32/+3/0.00/0.0/191/35 30 ENE AERO 25 ENE RMY N/A
12/25 35/21/28/0/0.73/3.2/098/18 50 W AERO 54 W RMY 47
12/26 24/13/19/-9/0.00/0.0/529/97 39 W AERO 39 W RMY 41
12/27 19/6/13/-15/0.00/0.0/534/98 28 WNW AERO 25 WNW RMY N/A
12/28 10/1/6/-22/0.00/0.0/546/100 37 WNW AERO 44 WNW RMY 43
12/29 13/-3/5/-22/0.00/0.0/164/30 25 W AERO 25 W RMY 27
12/30 14/1/8/-19/0.03/0.5/016/03 21 W AERO 18 W RMY 24
12/31 10/0/5/-22/0.00/0.0/175/32 32 WNW AERO 32 WNW RMY 35

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

RECORDS FOR JANUARY 11
HIGH 59F IN 1975
LOW -7F IN 1968
PRECIP 1.58 INS. IN 2008
SNOW 10.2 INS. 1927
PEAK GUST 95e MPH S IN 1980

RECORDS FOR JANUARY 12
HIGH 59F IN 2017
LOW -15F IN 1886
PRECIP 2.04 INS. IN 2011
SNOW 18.2 INS. IN 2011
WIND 84e MPH S IN 1980

TODAY’S REPORT PREPARED BY: Kaitlin Geagan