Tuesday, January 21, 2020
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, JANUARY 21, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME
ANOTHER SUNNY, BUT COLD DAY ATOP GREAT BLUE HILL….
Despite the abundance of sunshine today, the air mass
over the region continues to be of arctic origin.
Temperatures this morning were once again in the low teens,
and have only recovered to the mid 20s this afternoon.
Today will make the second below normal day in a row, and
only the 5th this month. The dew point has been sitting in
the lower single digits indicating how extremely the dry
the air is.
With the arctic air mass, very clear air is in place
and has resulted in visibility of around 70 miles most
of the day.
The high so far today is 24F, 10 degrees below the normal
high of 34F. The low since midnight is 10F, this is 7
degrees below the normal low of 17F.
Today’s Observations:
7 A.M.
Weather: Clear, stratocumulus offshore distant NE-SE
Temperature: 11F; Dew Point: 3F; Wind: NW at 6 kts
Sea-level pressure: 30.40 ins. Hg, rising, then more rapidly
Visibility: 70 miles
6-hr Max temp: 14F
6-hr Min temp: 10F
24-hr Precip: 0.00 ins.
24-hr Snowfall: 0.0 ins.
Snow depth: 2 ins.
BHO SA 1155 CLR 70 293/11/3/3306/040/ SC OFFSHR DSNT NE-SE WND LGT/
8/500 4/002 53026 10014 20010
10 A.M.
Weather: Clear, stratocumulus offshore distant NE-SE, few
cirrus distant W-N
Temperature: 19F; Dew Point: 2F; Wind: NW at 6 kts
Sea-level pressure: 30.43 ins. Hg, rising, then more slowly
Visibility: 70 miles
3-hr Precip: 0.00 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1455 CLR 70 305/19/2/3306/043/ SC OFFSHR DSNT NE-SE
FEW CI DSNT W-N WND LGT/ 8/501 51012
1 P.M.
Weather: Broken dense cirrus/cirrocumulus, thin broken cirrus,
stratocumulus offshore distant NE-SE
Temperature: 23F; Dew Point: 3F; Wind: WNW at 8 kts
Sea-level pressure: 30.39 ins. Hg, falling, then more slowly
Visibility: 70 miles
6-hr Max temp: 24F
6-hr Min temp: 10F
6-hr Precip: 0.00 ins.
6-hr Snowfall: 0.0 ins.
Snow depth: 2 ins
BHO SA 1755 E180 BKN 250 –BKN 70 292/23/3/2908/039/ SC OFFSHR
DSNT NE-SE AND DSNT SSE-S/ 8/502 4/002 56013 10024 20010
SUMMARY FOR MONDAY, JANUARY 20, 2020
TEMPERATURE (DEGREES F)
MAX…..26 NORMAL…..33
MIN…..12 NORMAL…..17
MEAN….19 NORMAL…..25
DEPARTURE FROM 30-YEAR NORMAL………………… -6
TOTAL DEPARTURE FOR THE MONTH………………..+166 [+8.1 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………46 DEPARTURE……. +6
TOTAL HEATING UNITS FOR THE MONTH…………..625 DEPARTURE……-163
TOTAL HEATING UNITS FOR THE SEASON…………2876 DEPARTURE……-217
TOTAL HEATING UNITS LAST SEASON TO DATE…….3037 DEPARTURE……-161
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..33 NW AT 12:16 A.M.
AERO…………………….32 NW AT 2:28 A.M.
ASOS…………………….33 NW AT 3:33 A.M.
DAVIS……………………33 NW AT 12:15 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………….26 NW AT 2:32 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….22 NW AT 2:32 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………23 NW AT 2:30 A.M.
AVERAGE WIND SPEED AND DIRECTION…………..13.3 NW
ASOS…………………..12.4
DAVIS………………….13.6 NW [313 deg.]
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……….0.89 DEPARTURE……-1.96
ASOS…………..0.89
TOTAL PRECIPITATION FOR THE YEAR………..0.89 DEPARTURE……-1.96
ASOS…………..0.89
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……… 0.0 DEPARTURE…….-0.5
TOTAL SNOWFALL FOR THE MONTH…………… 4.2 DEPARTURE…….-6.9
TOTAL SNOWFALL FOR THE SEASON…………..24.2 DEPARTURE…….-2.9
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 24/10/17/-8/0.00/0.0/…./.. 50 NW AERO 48 NW RMY N/A
01/18 28/8/18/-7/0.35/2.8/…./.. 28 WSW AERO 24 ESE RMY N/A
01/19 40/21/31/+6/0.02/0.2/…./.. 44 W AERO 44 W RMY 42
01/20 26/12/19/-6/0.00/0.0/…./.. 33 NW AERO 32 NW RMY N/A
01/21 The low since midnight is 10F, 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 21
HIGH 65F IN 1906
LOW -4F IN 1888,1893
PRECIP 2.49 INS. IN 1979
SNOWFALL 9.0 INS. IN 2014
PEAK GUST 78e MPH SE IN 1979
RECORDS FOR JANUARY 22
HIGH 59F IN 1916
LOW -8F IN 1888,1976
PRECIP 1.24 INS. IN 1891,1987
SNOWFALL 10.0 INS. IN 2005
PEAK GUST 67 MPH W IN 1976
TODAY’S REPORT PREPARED BY: Matt Douglas
