Friday, January 17, 2020

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, JANUARY 17, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

COLD TEMPERATURES AND BLUEBIRD SKIES RETURN
TO GREAT BLUE HILL….

Today we experienced continued northwesterly winds
gusting upwards of 46 MPH – yesterday peaked at
54 MPH! Temperatures have returned to typical January
cold with a low so far of 12 degrees. Despite the cold
wind chills, bright blue skies and perfect visibility
have been enjoyed throughout the day putting a nice
end to a fairly cloudy, dreary workweek.

The high so far today is 19 degrees, this
is 14 degrees above the normal high of 33 degrees.
The low since midnight is 12 degrees, this is 5
degrees below the normal low of 17 degrees.

PRELIMINARY STATS FOR DECEMBER 2019

TEMPERATURE, Deg. F
Avg. Max. 39.1 [0.0] Avg. Min. 25.0 [+1.4] Mean      32.1 [+0.8] 24-hour corrected mean: 32.3
Max. for month: 58F on the 10th
Min. for month: 9F on the 19th

HEATING DEGREE DAYS
Total heating units:   1014 [-29] Total for the season:  2251 [-54] Total for last season: 2295

PRECIPITATION, Inches
Total: 7.81 [+2.92] Greatest in 24 hrs: 1.64 inches on the 1st-2nd

SNOWFALL, Inches
Total: 19.9 [+6.5] Greatest in 24 hrs: 5.8 ins. on the 1st-2nd

WIND, mph
Avg. uncorrected wind speed: 13.2 mph
Avg. corrected wind speed:   13.6 mph
Prevailing wind direction:   W [20%] Peak gust and direction:     53 S,W on the 9th, 15th

SUNSHINE:
Campbell-Stokes card minutes: 6168 minutes of possible 16470 or 37%
Astronomical total minutes: 6368 minutes of possible 17000 or 37%

Today’s Observations:

7 A.M.
Weather: Clear, few distant cumulus offshore
Temperature: 13F; Dew Point: -2F; Wind: NW at 20G32 kts
Peak wind: 41 MPH (36 kts) NW at 6:28 A.M.
Sea-level pressure: 30.35 ins. Hg, rising unsteadily
Visibility: 60 miles
6-hr Max temp: 24F
6-hr Min temp: 13F
24-hr Precip:  0.04 ins.
24-hr Snowfall: Trace
BHO SA 1155 CLR 60 279/13/-2/3220G32/035/ FEW DSNT CU OFFSHR
PK WND 3236/28 TOTAL NEW SNOW LAST 24HRS TRACE/ 8/100 52048
70004 10024 20013

10 A.M.
Weather: Clear, few distant cumulus offshore
Temperature: 14F; Dew Point: -6F; Wind: NW at 21G33 kts
Peak wind: 46 MPH (40 kts) NW at 7:34 A.M.
Sea-level pressure: 30.47 ins. Hg, rising then rising more slowly
Visibility: 90 miles
3-hr Precip:  0.00 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1455 CLR 90 318/14/-6/3221G33/047/ FEW DSNT CU OFFSHR
PK WND 3240/1234/ 8/100 51039

1 P.M.
Weather: Clear, few distant cumulus offshore
Temperature: 19F; Dew Point: -9F; Wind: NW at 15G27 kts,
Peak wind: 44 MPH (38 kts) NW at 11:41 A.M.
Sea-level pressure: 30.48 ins. Hg, rising then falling
Visibility: 90 miles
6-hr Max temp: 19F
6-hr Min temp: 12F
6-hr Precip:  0.00 ins.
6-hr Snowfall: 0.0 ins.
BHO SA 1755 CLR 90 323/19/-9/3115G27/048/ FEW DSNT CU OFFSHR
PK WND 3138/1641/ 8/100 50005 10019 20012

SUMMARY FOR THURSDAY, JANUARY 16, 2020

TEMPERATURE (DEGREES F)
MAX…..42   NORMAL…..33
MIN…..24   NORMAL…..17
MEAN….33   NORMAL…..25

DEPARTURE FROM 30-YEAR NORMAL…………………+8
TOTAL DEPARTURE FOR THE MONTH………………..+179 [+11.0 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………32  DEPARTURE…….-8
TOTAL HEATING UNITS FOR THE MONTH…………..450  DEPARTURE……-178
TOTAL HEATING UNITS FOR THE SEASON…………2701  DEPARTURE……-231
TOTAL HEATING UNITS LAST SEASON TO DATE…….2874  DEPARTURE……-173

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..54 W   AT  11:44 A.M.
AERO…………………….52 W   AT  11:55 A.M.
ASOS…………………….55 WNW AT  11:51 A.M.
DAVIS……………………56 WNW AT  2:33 P.M. RMY 59
FASTEST MILE FOR YESTERDAY………………….43 W   AT  11:52 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….37(e)W AT  11:58 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………41 W   AT  11:49 A.M.
AVERAGE WIND SPEED AND DIRECTION………….. 18.3 NW
ASOS………………….. 18.6
DAVIS………………….18.2 WNW [297 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.04  DEPARTURE……-0.10
ASOS…………..0.04
TOTAL PRECIPITATION FOR THE MONTH……….0.52  DEPARTURE……-1.76
ASOS…………..0.55
TOTAL PRECIPITATION FOR THE YEAR………..0.52  DEPARTURE……-1.76
ASOS…………..0.55

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……… T    DEPARTURE…….-0.5
TOTAL SNOWFALL FOR THE MONTH…………… 1.2  DEPARTURE…….-7.8
TOTAL SNOWFALL FOR THE SEASON…………..21.2  DEPARTURE…….-3.8

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  32/16/24/-13/0.87/5.7/011/02           33 ENE AERO 32 ENE RMY N/A
12/02  37/25/31/-5/1.04/2.7/000/00            52 NE  AERO 47 NE  RMY 53
12/03  30/23/27/-9/0.52/3.1/000/00            32 N   AERO 35 N   RMY 36
12/04  34/22/28/-7/0.00/0.0/000/00            23 WNW AERO 23 NNW RMY N/A
12/05  41/26/34/-1/0.00/0.0/343/62            33 NW  AERO 35 NW  RMY 37
12/06  33/23/28/-7/0.02/0.1/000/00            25 NW  AERO 23 NW  RMY 29
12/07  31/18/25/-9/0.00/0.0/519/94            25 NW  AERO 23 NW  RMY N/A
12/08  36/15/26/-8/0.00/0.0/402/73            31 SSW AERO 32 SSW RMY N/A
12/09  57/36/47/+13/0.62/0.0/000/00           53 S   AERO 52 S   RMY 54
12/10  58/37/48/+15/0.28/0.0/044/08           35 SW  AERO 39 SW  RMY N/A
12/11  36/23/30/-3/0.48/4.8/236/43            25 NW  AERO 25 NW  RMY N/A
12/12  29/17/23/-10/0.00/0.0/488/89           29 W   AERO 30 W   RMY 25
12/13  46/22/34/+2/0.11/0.0/000/00            25 SSE AERO 25 SSE RMY N/A
12/14  58/46/52/+20/1.35/0.0/000/00           45 S   AERO 41 S   RMY N/A
12/15  48/28/38/+6/0.00/0.0/284/52            53 W   AERO 53 W   RMY 50
12/16  30/25/28/-3/0.00/0.0/000/00            36 W   AERO 36 W   RMY N/A
12/17  35/23/29/-2/0.79/1.0/000/00            22 NNW AERO 21 NE  RMY 23
12/18  33/18/26/-5/T/0.0/229/42               44 WNW AERO 45 WNW RMY N/A
12/19  20/9/15/-15/0.00/0.0/534/98            51 W   AERO 47 W   RMY N/A
12/20  29/11/20/-10/0.00/0.0/540/99           32 W   AERO 30 W   RMY 29
12/21  31/16/24/-6/0.00/0.0/163/30            16 SSE AERO 15 SSE RMY N/A
12/22  40/26/33/+4/0.00/0.0/212/39            23 SW  AERO 21 SW  RMY 23
12/23  54/33/44/+15/0.00/0.0/540/99           30 WSW AERO 30 SW  RMY 30
12/24  42/29/36/+7/0.00/0.0/507/93            30 NW  AERO 27 NW  RMY 30
12/25  42/25/34/+6/0.00/0.0/289/53            16 NNE AERO 16 N   RMY N/A
12/26  39/29/34/+6/0.00/0.0/174/32            22 ENE AERO 20 ENE RMY 22
12/27  47/31/39/+11/0.00/0.0/000/00           32 SSW AERO 30 SSW RMY 34
12/28  47/30/39/+11/0.00/0.0/470/86           23 W   AERO 22 W   RMY N/A
12/29  42/28/35/+8/0.08/0.0/383/70            22 WNW AERO 21 WNW RMY 23
12/30  36/32/34/+7/1.34/0.8/000/00            40 E   AERO 37 E   RMY 37
12/31  40/32/36/+9/0.33/0.0/000/00            35 E   AERO 32 E   RMY N/A

DAILY RECORDS FOR DECEMBER

12/01/19: DAILY RECORD SNOWFALL OF 5.8 INS.,
BREAKS PREVIOUS RECORD OF 2.0 INS. SET IN 1902.

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

01/01  38/30/34/+7/…./0.0/…./..           39 W   AERO 38 W   RMY 41
01/02  46/29/38/+11/0.00/0.0/…./..          28 SW  AERO 28 SW  RMY 30
01/03  46/40/43/+17/0.00/0.0/…./..          21 SW  AERO 18 SW  RMY N/A
01/04  46/36/41/+15/…./0.0/…./..          16 NNW AERO 16 NNW RMY N/A
01/05  36/24/30/+4/…./0.5/…./..           43 NW  AERO 46 NW  RMY 43
01/06  33/23/28/+2/T/T/…./..                26 W   AERO 21 W   RMY N/A
01/07  38/29/34/+8/…./0.4/…/..            30 WSW AERO 28 WSW RMY N/A
01/08  39/22/31/+5/…./0.4/…/..            50 W   AERO 46 WNW RMY 47
01/09  28/16/22/-4/…./0.0/…/..            43 WNW AERO 40 WNW RMY N/A
01/10  48/23/36/11/T/…./0.0/…/..          37 SW  AERO 37 SW  RMY 39
01/11  65/46/56/+31/…./0.0/…/..           53 SSW AERO 53 SSW RMY N/A
01/12  68/36/52/+27/…./0.0/…/..           60 SSW AERO 62 SSW RMY N/A
01/13  39/31/35/+10/0.01/T/…/..             21 NE  AERO 20 NE  RMY N/A
01/14  38/31/35/+10/0.01/0.0/…/..           16 W   AERO 15 W   RMY N/A
01/15  48/35/42/+17/0.00/0.0/…/..           24 W   AERO 23 W   RMY 24
01/16  42/24/33/+8/0.06/T/…/..              54 W   AERO 52 W   RMY 59

01/17 The low since midnight is 12F, daily normal minimum is 17F

DAILY RECORDS FOR JANUARY

1/11/20: DAILY RECORD MAXIMUM TEMPERATURE OF 65F,
BREAKS PREVIOUS RECORD OF 60F SET IN 1975.

1/11/20: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 46F,
BREAKS PREVIOUS RECORD OF 40F SET IN 1983.

1/12/20: DAILY RECORD MAXIMUM TEMPERATURE OF 68F,
BREAKS PREVIOUS RECORD OF 60 SET IN 2018.
TIES HIGHEST MAXIMUM FOR JANUARY,
ADDITIONAL 68F ON 1/26/1950.

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

RECORDS FOR JANUARY 17
HIGH 55F IN 1973,1995
LOW -8F IN 1907,1982
PRECIP 1.43 INS. IN 1956
SNOWFALL 13.4 INS. IN 1956
PEAK GUST 62 MPH S IN 1994

RECORDS FOR JANUARY 18
HIGH 62F IN 1973,1990
LOW -10F IN 1982
PRECIP 1.68 INS. IN 1915
SNOWFALL 13.0 INS. IN 1948
PEAK GUST 85 MPH SSE IN 2006

TODAY’S REPORT PREPARED BY: Andrew Swanson