Wednesday, December 11, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, DECEMBER 11, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

YESTERDAY’S TOTAL SNOW WAS 2.1 INCHES
TEMPERATURES GRADUALLY GETTING COLDER TODAY

The light snowfall of yesterday lasted close to
12 hours but the accumulation was slow to add up.
A total of 2 inches remains on the ground at the
summit today.
Winds have backed from west to southwest by noon
today ahead of an approaching trough which will
bring a cold front ushering in a re-enforcement
of colder and drier air.  Today was been one
of only a handful of sunny days this month.

Today’s Observations:

7 A.M.
Weather: Clear, stratocumulus layer along and offshore NE-distant SE-S
with thin fog and hazy, total new snow past 24 hours 2.0 inches
Temperature: 20F; Dew Point: 15F; Wind: WSW at 11 kts.
Sea-level pressure: 30.17 ins. Hg, rising then more slowly
Visibility: 30 miles, thin fog all quadrants and hazy
24-hr. snowfall: 2.1 inch
24-hr. precip: 0.14 inch
Total snow on ground at 7 a.m. 2 inches
6-hr. min temp: 19 F
BHO SA 1155 CLR 30 217/20/15/2511/017/ SC LYR ALG/OFFSHR DSNT NE-S
THN F HAZY ALQDS TOTAL NEW SNW PST 18 HTS 1.3 INS EVENT TOTAL 2.1 INS
8/500 4/002 51030 ASOS 70014 MANUAL 70014 10021 20019

10 A.M.
Weather: Clear, few cirrus E-SSW, distant haze.
Temperature: 25F; Dew Point: 15F; Wind: SW at 11G22 kts,
Wind: Variable from S-WSW
Sea-level pressure: 30.21 ins. Hg, rising then more slowly
Visibility: 35 miles, distant haze
BHO SA 1455 CLR 35 230/25/15/2311G22/021/ FEW CI E-SSW DSNT HZ
WND 19V25/ 8/001 51013

1 P.M.
Weather: Broken dense cirrus, overcast cirrus, cumulus fractus,
cumulus and stratocumulus all quadrants, thin spots in the
overcast, and small break in overcast, distant haze
Temperature: 27F; Dew Point: 18F; Wind: SW at 13G20 kts.
Wind: Direction variable S to WSW
Sea-level pressure: 30.14 ins. Hg, falling then falling more slowly
Visibility: 30 miles, hazy
BHO SA 1755 180 SCT 220 BKN 250 OVC 30 208/27/18/2313G20/014/
FEW CUFRA/CU/SC ALQDS THN SPTS/SML BINOVC VC WND 19V25/ HAZY
8/832 56022 10028 20020

WEATHER SUMMARY FOR TUESDAY, DECEMBER 10, 2013

TEMPERATURE (DEGREES F)
MAX…..33    NORMAL…..41
MIN…..21    NORMAL…..26
MEAN….27    NORMAL…..33

DEPARTURE FROM 30-YEAR NORMAL………………….-6
TOTAL DEPARTURE FOR THE MONTH………………….+9 [+0.7 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..38  DEPARTURE………+6
TOTAL HEATING UNITS FOR THE MONTH………….292  DEPARTURE………-9
TOTAL HEATING UNITS FOR THE SEASON………..1516  DEPARTURE……..-47
TOTAL HEATING UNITS LAST SEASON TO DATE……1384  DIFFERENCE……+132

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………28 W   AT 10:17 P.M.
AERO…………………..28 W   AT 10:17 P.M.
ASOS…………………..30 W   AT 10:17 P.M.
DAVIS………………….26 W   AT 10:17 P.M. RMY 28
FASTEST MILE FOR YESTERDAY………………..24 W   AT 10:44 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..22 W   AT 10:40 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….19 W   AT 11:24 P.M.
AVERAGE WIND SPEED AND DIRECTION…………11.5 W
ASOS…………………11.4
DAVIS………………..10.4 W  [270 degrees] * last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.14  DEPARTURE………….-0.03
ASOS…………..0.14
TOTAL PRECIPITATION FOR THE MONTH……….1.29  DEPARTURE………….-0.36
ASOS…………..1.26
TOTAL PRECIPITATION FOR THE YEAR……….47.89 DEPARTURE…………..-2.29
ASOS…………..N/A**
** ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…….2.1     DEPARTURE………….+1.7
TOTAL SNOWFALL FOR THE MONTH………….2.7     DEPARTURE………….-0.5
TOTAL SNOWFALL FOR THE SEASON…………2.9     DEPARTURE………….-2.9

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2013 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane wind recording system gust
RMY:  RMY = R.M. Young wind gust recording system added 8/9/2011
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized

12/1  45/30/38/+1/0.28/T/000/00           22 SSE AERO 23 MPH SSE RMY 23
12/2  38/34/36/0/T/0.0/000/00             15 NW  AERO 15 MPH NW  RMY 16
12/3  45/32/39/+3/0.00/0.0/…/..         18 NNW AERO 18 MPH NNW RMY 20
12/4  43/29/36/+1/0.00/0.0/…/..         21 WNW AERO 21 MPH WNW RMY 21
12/5  53/38/46/+11/0.02/0.0/000/00        36 S   AERO 40 MPH S   RMY 39
12/6  55/33/44/+9/0.38/T/000/00           25 SSW AERO 28 MPH SSW RMY N/A
12/7  40/26/33/-1/0.12/T/…/..           23 NW  AERO 25 MPH NW  RMY N/A
12/8  30/22/26/-8/T/T/…/..              25 NW  AERO 27 MPH NW  RMY N/A
12/9  41/25/33/-1/0.35/0.6/000/00         28 E   AERO 28 MPH E   RMY 24
12/10 33/21/27/-6/0.14/2.1/000/00         28 W   AERO 28 MPH W   RMY 28

12/11 morning low temp: 19F; the normal low is now 25F

DAILY RECORDS FOR DECEMBER 2013
None so far.

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

RECORDS FOR DECEMBER 11
HIGH 63 IN 1911
LOW -1 IN 1988
PRECIP 2.36 INS. IN 1992
SNOWFALL 6.0 INS. IN 1894
PEAK GUST 78 S IN 1969

RECORDS FOR DECEMBER 12
HIGH 67 IN 1979
LOW -3 IN 1988
PRECIP 3.94 INS. IN 1992
SNOWFALL 20.3 INS. IN 1960
PEAK GUST 75 MPH SSE IN 2008

TODAY’S REPORT PREPARED BY: Robert Skilling/Rob Megnia