Tuesday, January 6, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, JANUARY 6, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

COLDEST AIR OF THE SEASON ARRIVES FOLLOWING
GUSTY MONDAY, WINDS GUST TO 48 MPH

Monday was a day of transition as our maximum was
recorded at 12:00 AM EST at 46F, while our minimum
was recorded at midnight this morning for Monday
at 13F. Gusty westerly winds averaged 23.5 MPH, our
windiest day since November 24th saw 23.8 MPH. The peak
gust for yesterday was recorded at 5:22 PM EST from the
W at 48 MPH, while the ASOS anemometer recorded 53 MPH.

Temperatures continued to slide through the early
morning hours today, bottoming out at 11F, our coldest
reading for the season so far. Winds have remained fairly
light; however, winds chills have also remained just
above 0F.

Skies have been overcast throughout the morning and
into the early afternoon with light snow beginning
at 11:13 AM EST. Visibility was reduced at that time,
and at the time of the 1:00 PM EST observation to 2
miles in all directions. 0.1 inches of new snow with
a liquid equivalent of 0.01 inches of water were recorded
at that time with a maximum reading of 15F so far today.

The corrected mean wind speed for December 2014 of
12.2 mph was the lowest on record for the month, and
the annual mean wind speed for 2014 of 12.3 mph was
the third lowest on record.

BHO December Mean Wind Speed, mph (1885-2014)

1) 12.2 in 2014
2) 12.3 in 2013
3) 12.9 in 2001
4) 13.0 in 2012
5) 13.1 in 2007

BHO Annual Mean Wind Speed, mph (1885-2014)

1) 11.8 in 2012
2) 12.2 in 2013
3) 12.3 in 2014
4) 12.5 in 2011
5) 12.6 in 2008
12.6 in 2009

SOME OF THE DECEMBER 2014 PRELIMINARY STATS

TEMPERATURE:  Deg. F
Av. Max. 42.0
Av. Min. 29.3
MEAN     35.7 [+4.3] 24-hour corrected mean: 35.5
Max. temp: 63 deg. Dec.  1
Min. temp: 14 deg. Dec. 31
Total heating degree day units:   901 [-135] Total heating degree day units
for the season beginning July 1: 2060 [-245]

PRECIPITATION: Ins.
Total: 7.21 [+2.32] Greatest in 24 hours;
Snowfall:  2.3 [-11.1] Seasonal: 11.0 [-5.0 ]

WIND:
Av. uncorrected wind speed: 11.8 MPH
Av.   corrected wind speed: 12.2 MPH
Prevailing wind direction: W @ 14%

SUNSHINE:
Astronomical total minutes:   5880/16999 or 35%
Campbell-Stokes card minutes: 5688/16470 or 35%

Today’s Observations:

7 A.M.
Weather: Overcast altostratus, few stratocumulus
distant offshore NNE-SSW
Temperature: 12F; Dew Point: 3F; Wind: W at 8 kts
Sea-level pressure: 30.34 ins. Hg, falling, then rising, but lower
Visibility: 50 miles
6-hr max temp: 12F
6-hr min temp: 11F
24-hr precip.: 0.00 ins
24-hr snowfall: 0.0 ins
BHO SA 1155 E170 OVC 50 273/12/3/2708/034/
FEW SC DSNT OFFSHR NNE-SSW/ 8/51/ 55005 10012 20011

10 A.M.
Weather: Overcast altostratus, few stratocumulus distant
offshore NE-ESE
Temperature: 14F; Dew Point: 2F; Wind: W at 7 kts,
Sea-level pressure: 30.33 ins. Hg, falling, then more quickly
BHO SA 1455 E90 OVC 70 272/14/2/2607/033/
FEW SC DSNT OFFSHR NE-ESE/ 8/52/ 58001

1 P.M.
Weather: Light snow, overcast stratus, sun dimly visible
Temperature: 15F; Dew Point: 12F; Wind: estimated SW at 4 kts,
Wind Speed: Light
Sea-level pressure: 30.21 ins. Hg, falling, then more quickly
Visibility: 2 miles, obscured by light snow
6-hr max temp: 15F
6-hr min temp: 12F
6-hr precip.: 0.01 ins
6-hr snowfall: 0.1 ins
BHO SA 1755 E15 OVC 2S- 230/15/12/E2204/021/
SUN DMLY VSBL NEW SNW PST 3 HRS 0.1 INS WND LGT/
8/6// 58042 ASOS 60001 MANUAL 60001 10015 20012

SUMMARY FOR MONDAY, JANUARY 5, 2015

TEMPERATURE (DEGREES F)
MAX…..46   NORMAL…..34
MIN…..13   NORMAL…..18
MEAN….30   NORMAL…..26

DEPARTURE FROM 30-YEAR NORMAL……………………..+4
TOTAL DEPARTURE FOR THE MONTH…………………….+25 [+4.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..35  DEPARTURE………..-4
TOTAL HEATING UNITS FOR THE MONTH………….168  DEPARTURE……….-25
TOTAL HEATING UNITS FOR THE SEASON………..2228  DEPARTURE………-269
TOTAL HEATING UNITS LAST SEASON TO DATE……2520  DIFFERENCE……..-292

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………48 W    AT   5:22 P.M.
ASOS…………………..53 W    AT   5:22 P.M.
DAVIS………………….50 W    AT   5:30 P.M. RMY 54
FASTEST MILE FOR YESTERDAY………………..42 W    AT  11:19 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..40 W    AT  10:30 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….36 W    AT  10:31 P.M.
AVERAGE WIND SPEED AND DIRECTION………….23.5 W
ASOS………………….21.8
DAVIS…………………19.7 WNW [285 degrees]

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……….1.15  DEPARTURE…..+0.43
ASOS…………..1.17
TOTAL PRECIPITATION FOR THE YEAR………..1.15  DEPARTURE…..+0.43
ASOS…………..1.17

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……-0.5
TOTAL SNOWFALL FOR THE MONTH…………….2.5  DEPARTURE……-0.3
TOTAL SNOWFALL FOR THE SEASON…………..13.5  DEPARTURE……-7.2

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER-JANUARY CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY 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

12/1  63/37/50/+13/0.01/0.0/391/70             28 WNW RMY 31
12/2  37/30/34/-2/0.10/T/000/00                26 E   RMY 29
12/3  49/34/42/+6/0.31/0.0/000/00              40 W   RMY 43
12/4  41/27/34/-1/0.00/0.0/505/91              29 WNW RMY N/A
12/5  42/23/33/-2/0.12/0.0/382/69              21 E   RMY 22
12/6  43/36/40/+5/0.99/0.0/000/00              25 NNW RMY N/A
12/7  36/18/27/-7/0.15/0.0/193/35              31 N   RMY 34
12/8  25/16/21/-13/0.01/0.1/000/00             24 N   RMY N/A
12/9  48/25/37/+3/3.23/0.0/000/00              48 ENE RMY 52
12/10 47/35/41/+8/0.42/0.0/000/00              35 NNE RMY 37
12/11 35/29/32/-1/0.05/0.5/000/00              27 SW  RMY 27
12/12 36/26/31/-2/0.00/0.0/230/42              23 WNW RMY 25
12/13 40/27/34/+2/0.00/0.0/191/35              28 NW  RMY 28
12/14 43/28/36/+4/0.00/0.0/377/69              20 NW  RMY 20
12/15 41/28/35/+3/0.00/0.0/535/98              17 NW  RMY 17
12/16 42/33/38/+7/T/T/011/02                   17 E   RMY N/A
12/17 45/37/41/+10/0.43/0.0/000/00             27 W   RMY N/A
12/18 41/32/37/+6/0.02/T/213/39                35 WNW RMY 38
12/19 34/25/30/0/0.00/0.0/000/00               26 NW  RMY 29
12/20 32/24/28/-2/0.11/1.0/164/30              21 NNE RMY 23
12/21 31/29/30/+0/0.08/0.7/000/00              20 NNE RMY 22
12/22 42/29/36/+7/0.01/0.0/038/07              23 E   RMY N/A
12/23 44/39/42/+13/0.31/0.0/000/00             28 ENE RMY 30
12/24 61/40/51/+22/0.63/0.0/000/00             32 SSW RMY 41
12/25 61/41/51/+23/0.21/0.0/213/39             37 W   RMY 43
12/26 47/35/41/+13/0.00/0.0/540/99             24 WSW RMY 28
12/27 50/35/43/+15/0.00/0.0/519/95             21 SSW RMY N/A
12/28 49/35/42/+14/0.02/0.0/038/07             31 W   RMY 36
12/29 41/26/34/+7/0.00/0.0/470/86              23 WNW RMY 23
12/30 27/16/22/-5/0.00/0.0/470/86              22 NW  RMY N/A
12/31 28/14/21/-6/0.00/0.0/400/73              23 W   RMY N/A

1/1   31/18/25/-2/0.00/0.0/…/..              29 SSW RMY 30
1/2   37/26/32/+5/0.00/0.0/…/..              35 WSW RMY 38
1/3   34/21/28/+2/0.67/2.5/…/..              25 SE  RMY 26
1/4   51/33/42/+16/0.48/0.0/000/00             30 SSW RMY N/A
1/5   46/13/30/+4/0.00/0.0/…/..              48 W   RMY 54

1/6 morning low temp: 11F since midnight; normal low is now 18F

DAILY RECORDS FOR DECEMBER 2014:

-DAILY PRECIPITATION RECORD FOR DECEMBER 9 2014
Old record of 1.51 inches set in 1952,
replaced with new record of 3.23 inches.

-DAILY TEMPERATURE RECORD FOR DECEMBER 24 2014
Old record of 58F set in 1996,
replaced with new record of 61F.

DAILY RECORDS FOR JANUARY 2015
None so far.

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

RECORDS FOR JANUARY 6
HIGH 66F IN 2007
LOW -14F IN 1896
PRECIP 3.10 INS. IN 1889 [RECORD FOR MONTH] SNOWFALL 7.5 INS. IN 1893
PEAK GUST 70 MPH WNW IN 1959

RECORDS FOR JANUARY 7
HIGH 60F IN 1930
LOW -7F IN 1896
PRECIP 1.97 INS. IN 1977
SNOWFALL 16.0 INS. IN 1977
PEAK GUST 74 MPH NW IN 1968

TODAY’S REPORT PREPARED BY: Brian Fitzgerald