Sunday, January 20, 2019

| January 20, 2019 | Reply

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, JANUARY 20, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

FULL SPECTRUM PRECIPITATION ON DISPLAY AS STORM BARRELS
THROUGH NEW ENGLAND…

With last night’s snowfall proving to be the first significant
accumulation of the new year, the storm quickly transitioned to rain
overnight, and then later to freezing rain as mixing cold air began
to produce some observable effects.  Rainfall amounts proved to be
significant, with 1.07″ of liquid precipitation recorded at the 7 A.M.
observation, a total which includes the melted down 4.2″ of snowfall.
Rain began shifting to freezing rain around 9:30 A.M., and gradually
transitioning towards precipitation in the form of ice pellets, but
not before producing a healthy coating of glaze ice during the
freezing rain event. Since then, precipitation has returned back to
freezing rain, with the shift occurring around noon, this being a
large indicator of warmer air aloft despite surface temperatures
remaining largely below freezing.  Winds have shifted from easterlies
heading into the nighttime hours yesterday, to a more northeasterly
direction through the day today.  Temperatures continue to drop as
cold air streams into the area, with a low temperature of 25 F reached
by the time of the 1 P.M. observation.  Atmospheric pressure also
continues to drop to strikingly low readings with a low station
pressure of 967 mb eclipsed just before the 1 P.M. observation.

Today’s Observations:

7 A.M.
Weather: Moderate Rain, fog
Temperature: 33F; Dew Point: 33F; Wind: NE at 17G26 kts
Sea-level pressure: 29.61 ins. Hg, falling rapidly, then more slowly
Visibility: 1/8 mile
6-hr Max temp: 33F
6-hr Min temp: 29F
24-hr Precip: 1.07
24-hr snowfall: 4.2
Snow depth: 4 ins.
BHO SA 1155 X W2 1/8RF 026/33/33/0417G26/961/ 8//// 4/004 56069 60///
70107 10033 20029

10 A.M.
Weather: Freezing rain, fog
Temperature: 29F; Dew Point: 29F; Wind: N at 11G13 kts
Sea-level pressure: 29.47 ins. Hg, falling, then more rapidly
Visibility: 1/16 mile
3-hr Precip: 0.53 ins.
BHO SA 1455 X W1 1/16ZRF 981/29/29/3511G13/947/ 8//// 56045 6053/

1 P.M.
Weather: Freezing rain, fog
Temperature: 26F; Dew Point: 26F; Wind: NE at 16G23 kts,
Sea-level pressure: 30.27 ins. Hg, decreasing, then more rapidly
Visibility: 1/8 mile
6-hr Max temp: 33F
6-hr Min temp: 25F
6-hr Precip: 0.79 ins.
6-hr snowfall: 0.00 ins.
Snow depth: 3 ins.
BHO SA 1755 X W2 1/8ZRF 903/26/26/0816G23/924/ 8//// 4/003 58078
6079/ 10033 20025

SUMMARY FOR SATURDAY, JANUARY 19, 2019

TEMPERATURE (DEGREES F)
MAX…..31   NORMAL…..33
MIN…..24   NORMAL…..17
MEAN….28   NORMAL…..25

DEPARTURE FROM 30-YEAR NORMAL……………………+3
TOTAL DEPARTURE FOR THE MONTH…………………..+54 [+2.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..37   DEPARTURE………-3
TOTAL HEATING UNITS FOR THE MONTH………….695   DEPARTURE……..-53
TOTAL HEATING UNITS FOR THE SEASON………..2991   DEPARTURE……..-61
TOTAL HEATING UNITS LAST SEASON TO DATE..2933  DIFFERENCE…….+58

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..30  E   AT  9:18 P.M.
AERO…………………….30  E   AT  9:17 P.M.
ASOS…………………….33  E   AT  9:20 P.M.
DAVIS……………………33  E   AT  9:19 P.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………….24  E   AT  9:15 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….25  E   AT  9:21 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………24  E   AT  9:22 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..10.7 E
ASOS…………………..10.6
DAVIS………………….10.7 NE [56 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….1.07  DEPARTURE…….+0.93
ASOS…………..1.05
TOTAL PRECIPITATION FOR THE MONTH……….3.21  DEPARTURE…….+0.51
ASOS…………..3.20
TOTAL PRECIPITATION FOR THE YEAR………..3.21  DEPARTURE…….+0.51
ASOS…………..3.20

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….4.2  DEPARTURE……..+3.7
TOTAL SNOWFALL FOR THE MONTH…………….4.2  DEPARTURE……..-6.5
TOTAL SNOWFALL FOR THE SEASON…………..11.9  DEPARTURE…….-14.8

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 54/29/42/+15/…./0.0/…/..      53 W   AERO 53 W   RMY 54
01/02 34/24/29/+2/…./…/…/..          22 NW  AERO 22 NW  RMY N/A
01/03 42/28/35/+9/0.01/T/…/..        28 WNW AERO 30 WNW RMY 30
01/04 43/30/37/+11/…./…/…/..         29 SW  AERO 29 SW  RMY 29
01/05 41/32/37/+11/1.19/…/…/..      26 NE  AERO 25 NNW RMY 27
01/06 42/21/32/+6/0.00/0.0/…/..      42 NW  AERO 46 NW  RMY 50
01/07 26/14/20/-6/…/…/…/..         37 NW  AERO 41 NW  RMY N/A
01/08 40/24/32/+6/…/…/…/..            24 SSE AERO 23 SSE RMY N/A
01/09 42/31/37/+11/…/…/…/..          44 W   AERO 46 WNW RMY 45
01/10 32/20/26/+1/T/T/…/..              37 NW  AERO 41 NW  RMY 43
01/11 26/12/19/-6/0.00/0.0/…/..        36 WNW AERO 37 WNW RMY 38
01/12 26/9/18/-7/0.00/0.0/…/..          32 NW  AERO 32 NW  RMY 29
01/13 25/11/18/-7/0.00/0.0/…/..        18 NNW AERO 16 NW  RMY N/A
01/14 27/20/24/-1/0.00/0.0/…/..         20 NNE AERO 17 N   RMY N/A
01/15 34/18/26/1/0.00/0.0/…/..          22 NW  AERO 21 NNW RMY N/A
01/16 34/23/29/+4/0.00/0.0/…/..        33 W   AERO 32 W   RMY 35
01/17 27/13/20/-5/0.00/0.0/…/..         30 NNW AERO 28 NW  RMY N/A
01/18 40/21/31/+6/0.00/0.0/…/..        18 WNW AERO 18 WNW RMY N/A
01/19 31/24/28/+3/…/1.6/…/..            30 E   AERO 30 E   RMY N/A

01/20 Low temp since midnight is 25F; normal low is 17F

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

RECORDS FOR JANUARY 20
HIGH 59F IN 1951
LOW -9F IN 1901
PRECIP 1.95 INS. IN 1978
SNOWFALL 19.0 INS. IN 1978
PEAK GUST 76e MPH NE IN 1978

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

TODAY’S REPORT PREPARED BY: Nate Iannuccillo

Category: Daily Discussions

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