Thursday, December 26, 2019

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, DECEMBER 26, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

DRY WEATHER CONTINUES, BUT CLOUDY AND COOL TODAY…

The dry stretch of weather continues as we’ve gone a solid
week and a half now without any measurable precipitation.
Despite the recent dryness, the month is averaging well above
normal in the precipitation department, with our monthly total
of 6.06″ currently running 2.03″ above normal to date. It does
appear we may add to the monthly total as we get into late this
weekend and/or early next week.

Today has turned out to be a mostly cloudy day with the wind
coming in off the ocean. This onshore flow has allowed a layer
of lower stratocumulus to overtake the area giving us an
overcast sky early this afternoon.

Visibility today has been limited, thanks to a smoke layer this
morning and just hazy air early this afternoon. 30 miles was
all we could muster all morning, it has only improved to about
40 miles early this afternoon.

The ocean flow has also helped to keep temperatures from
getting as mild as the past few days. The high so far today
is 39F, which is 3 degrees above the daily normal maximum of
36F. The low since midnight is 32F, which is 12 degrees above
the normal minimum of 20F.

Today’s Observations:

7 A.M.
Weather: Scattered altocumulus, overcast dense cirrus
Temperature: 32F; Dew Point: 28F; Wind: NNE at 9 kts
Sea-level pressure: 30.33 ins. Hg, rising, then more rapidly
Visibility: 30 miles, hazy
6-hr Max temp: 34F
6-hr Min temp: 32F
24-hr Precip:  0.00 ins.
24-hr Snowfall: 0.0 ins.
Snow Depth: Trace
BHO SA 1155 160 SCT E200 OVC 30 270/32/28/0209/033/
BINOVC N-ESE FEW SC DSNT NNE-E THN K LYR ALNG HRZN ALQDS
HAZY/ 8/572 53024 10034 20031

10 A.M.
Weather: Scattered altocumulus, thin overcast cirrus
Temperature: 38F; Dew Point: 27F; Wind: NE at 5 kts,
Sea-level pressure: 30.38 ins. Hg, rising, then more rapidly
Visibility: 30 miles, hazy
3-hr Precip:  0.00 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1455 170 SCT E250 –OVC 30 287/38/27/0405/038/
FEW SC N-NE-SE PTCHY DENSE CI/CS ALQDS THN K LYR ALQDS
HAZY WND LGT/ 8/572 53017

1 P.M.
Weather: Overcast stratocumulus
Temperature: 36F; Dew Point: 28F; Wind: ENE at 8G16 kts
Sea-level pressure: 30.38 ins. Hg, falling then rising
Visibility: 40 miles, hazy
6-hr Max temp: 39F
6-hr Min temp: 32F
6-hr Precip:  0.00 ins.
6-hr Snowfall: 0.0 ins.
Snow Depth: Trace
BHO SA 1755 E25 OVC 40 287/36/28/0708G16/038/ FEW BINOVC
ALQDS HAZY WND 02V10/ 8/5// 55000 10039 20032

SUMMARY FOR WEDNESDAY, DECEMBER 25, 2019

TEMPERATURE (DEGREES F)
MAX…..42   NORMAL…..36
MIN…..25   NORMAL…..21
MEAN….34   NORMAL…..28

DEPARTURE FROM 30-YEAR NORMAL………………….+6
TOTAL DEPARTURE FOR THE MONTH…………………-25 [-1.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………31  DEPARTURE……..-6
TOTAL HEATING UNITS FOR THE MONTH…………..841  DEPARTURE…….+23
TOTAL HEATING UNITS FOR THE SEASON…………2078  DEPARTURE……..-2
TOTAL HEATING UNITS LAST SEASON TO DATE…….2111  DEPARTURE…….-33

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..16 NNE AT  3:08 A.M.
AERO…………………….16 N   AT  1:46 A.M.
ASOS…………………….17 N   AT  1:54 A.M.
DAVIS……………………17 N   AT  1:47 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………….14 N   AT  1:34 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….14 N   AT  1:47 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………14 N   AT  1:45 A.M.
AVERAGE WIND SPEED AND DIRECTION………….. 6.0 SSW
ASOS………………….. 6.9
DAVIS…………………. 6.5 N   [002 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.16
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….6.06  DEPARTURE……+2.03
ASOS…………..6.51
TOTAL PRECIPITATION FOR THE YEAR……….55.14  DEPARTURE……+2.57
ASOS………….55.91

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE…….-0.5
TOTAL SNOWFALL FOR THE MONTH……………19.1  DEPARTURE…….+8.9
TOTAL SNOWFALL FOR THE SEASON…………..19.2  DEPARTURE…….+6.4

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/…./5.8/011/02           33 ENE AERO 32 ENE RMY N/A
12/02  37/25/31/-5/…./2.7/000/00            52 NE  AERO 47 NE  RMY 53
12/03  30/23/27/-9/…./4.6/000/00            32 N   AERO 35 N   RMY 36
12/04  34/22/28/-7/…./0.0/000/00            23 WNW AERO 23 NNW RMY N/A
12/05  41/26/34/-1/…./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/…/..            31 SSW AERO 32 SSW RMY N/A
12/09  57/36/47/+13/…./0.0/…/..           53 S   AERO 52 S   RMY 54
12/10  58/37/48/+15/…./0.0/…/..           35 SW  AERO 39 SW  RMY N/A
12/11  36/23/30/-3/…./3.0/…/..            25 NW  AERO 25 NW  RMY N/A
12/12  29/17/23/-10/…./1.8/…/..           29 W   AERO 30 W   RMY 25
12/13  46/22/34/+2/…./0.0/…/..            25 SSE AERO 25 SSE RMY N/A
12/14  58/46/52/+20/…./0.0/…/..           45 S   AERO 41 S   RMY N/A
12/15  48/28/38/+6/0.00/0.0/…/..            53 W   AERO 53 W   RMY 50
12/16  30/25/28/-3/0.00/0.0/…/..            36 W   AERO 36 W   RMY N/A
12/17  35/23/29/-2/…./1.0/…/..            22 NNW AERO 21 NE  RMY 23
12/18  33/18/26/-5/…/0.0/…/..             44 WNW AERO 45 WNW RMY N/A
12/19  20/9/15/-15/…/0.0/…/..             51 W   AERO 47 W   RMY N/A
12/20  29/11/20/-10/0.00/0.0/…./..          32 W   AERO 30 W   RMY 29
12/21  31/16/24/-6/0.00/0.0/…./..           16 SSE AERO 15 SSE RMY N/A
12/22  40/26/33/+4/0.00/0.0/…./..           23 SW  AERO 21 SW  RMY 23
12/23  54/33/44/+15/0.00/0.0/…./..          30 WSW AERO 30 SW  RMY 30
12/24  42/29/36/+7/0.00/0.0/…./..           30 NW  AERO 27 NW  RMY 30
12/25  42/25/34/+6/0.00/0.0/…./..           16 NNE AERO 16 N   RMY N/A

12/26 The low since midnight is 32F, daily normal minimum is 20F

DAILY RECORDS FOR DECEMBER

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

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

RECORDS FOR DECEMBER 26
HIGH 58 IN 1973,1982
LOW -12 IN 1980
PRECIP 3.64 INS. IN 1969
SNOWFALL 17.5 INS. IN 1909
PEAK GUST 84 MPH SSE IN 1957

RECORDS FOR DECEMBER 27
HIGH 57 IN 1895,1949
LOW -4 IN 1903
PRECIP 2.43 INS. IN 1969
SNOWFALL 11.2 INS. IN 1947
PEAK GUST 73 S IN 2011

TODAY’S REPORT PREPARED BY: Matt Douglas