Wednesday, November 13, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, NOVEMBER 13, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

COLDEST OF SEASON TO DATE AT 21F THIS MORNING
FIRST MEASURABLE SNOW OF THE SEASON YESTERDAY
A TRACE OF SNOW REMAINS ON GROUND THIS MORNING

YESTERDAY…
The rain/slush mix abruptly transitioned to all snow at approximately
7:21 a.m.  The transition from rain to snow was quite apparent.  A wall of
white could be seen slowly progressing southward across the area, eventually
enveloping the summit beginning at 7:21 a.m.

Check out the member area of bluehill.org for a photo.

Snowfall reached 0.2 inch on the summit, making this the first measurable
snowfall of the season.  The liquid to snow ratio was 1:4 or 5.  Light
accumulation was visible on nearby Chickatawbut Hill (3 miles E).  Little
if any accumulation was visible below an elevation of about 450-500 feet.
A trace of snow was still on the ground early this morning.
The record snowfall for November 12 is 8.1 inches in 1987.

Light snow was observed on Sunday, November 3 and Friday, November 8, but
no accumulation occurred on those dates.

The long term (1886-2012) average date of the first snowfall is November 18,
and the 30-year (1981-2010) average date of the first snowfall is
November 20.  Last year, the first measurable snowfall occurred on
November 7 with 3.5 inches.

TODAY…
A low temperature of 21F (21.0 in Hazen shelter) surpassed
24F for yesterday, occurring at midnight last night, and 27F
back on November 4. This morning minimum was 13 degrees colder
than average for the date, but well short of the record of
14F established in 1926. In addition, 21 degrees was the coldest
it has been since 18F last March 18.

Today’s Observations:

7 A.M.
Weather: Clear, stratocumulus/cumulus layer along and offshore
NE-SE and distant SSE, few stratocumulus along horizon distant
to the WNW-NNW
Temperature: 22F; Dew Point: 14F; Wind: WNW at 13 kts,
Wind: Wind chill 10F
Sea-level pressure: 30.25 ins. Hg, rising then rising more rapidly
Visibility: 60 miles, except 70 miles NW, light rain and thin fog all quadrants
6-hr min temp: 21F
24-hr precip: 0.06 inch
24-hr snowfall: 0.2 inch
BHO SA 1155 CLR 60 243/22/14/3013/025/ SC/CU LYR ALG/OFFSHR NE-SE
AND DSNT SSE FEW SC ALG HRZN DSNT WNW-NW VSBY NW 70 LGT DSNT HZ
WNDCHILL 10F TOTAL NEW SNW PST 24 HRS 0.2 IN/ 8/800 53012
MANUAL 70006 ASOS 70007 10023 20021

10 A.M.
Weather: Clear, stratocumulus/cumulus layer distant offshore NE-SE,
few stratocumulus along horizon distant WNW-NNW
Temperature: 28F; Dew Point: 13F; Wind: NW at 14 kts,
Wind: Direction variable W-NNW
Sea-level pressure: 30.28 ins. Hg, rising then rising more slowly
Visibility: 75 miles, light distant haze
BHO SA 1455 CLR 75 253/28/13/3214/028/ SC/CU LYR DSNT OFFSHR NE-SE
FEW SC DSNT WNW-NNW ALG HRZN/ LGT DSNT HZ WND 28V34/ 8/800 51010

1 P.M.
Weather: Clear, stratocumulus/cumulus distant offshore ENE-SE,
few cumulus/stratocumulus distant NW-NNW
Temperature: 34F; Dew Point: 15F; Wind: NW at 11 kts,
Wind: Direction variable W-NNW
Sea-level pressure: 30.23 ins. Hg, falling then falling more rapidly
Visibility: 80 miles, light distant haze
6-hr max temp: 35F
BHO SA 1755 CLR 80 237/34/15/3111/023/ SC/CU DSNT ENE-SE OFFSHR
FEW CU/SC DSNT NW-N LGT DSNT HZ WND 26V33/ 8/800 58016 10035 20022

WEATHER SUMMARY FOR TUESDAY, NOVEMBER 12, 2013

TEMPERATURE (DEGREES F)
MAX…..48    NORMAL…..51
MIN…..24    NORMAL…..35
MEAN….36    NORMAL…..43

DEPARTURE FROM 30-YEAR NORMAL………………….-7
TOTAL DEPARTURE FOR THE MONTH………………….+2 [+0.0 DEGREE/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..29  DEPARTURE………+7
TOTAL HEATING UNITS FOR THE MONTH………….247  DEPARTURE………+3
TOTAL HEATING UNITS FOR THE SEASON…………724  DEPARTURE……..-83
TOTAL HEATING UNITS LAST SEASON TO DATE…….669  DIFFERENCE…….+55

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………42 SW  AT  1:19 A.M.
AERO…………………..43 SW  AT  1:19 A.M.
ASOS…………………..45 SW  AT  1:20 A.M.
DAVIS………………….41 SW  AT  1:19 A.M.
FASTEST MILE FOR YESTERDAY………………..30 WSW AT  2:06 A.M. *
MAXIMUM 2-MINUTE ASOS AVERAGE……………..30 SW  AT  1:20 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….28 WSW AT  1:40 A.M.
AVERAGE WIND SPEED AND DIRECTION…………14.2 NW
ASOS…………………14.0
DAVIS………………..12.3 WNW [300 degrees] * last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.06   DEPARTURE…………-0.10
ASOS…………..0.07
TOTAL PRECIPITATION FOR THE MONTH……….0.66   DEPARTURE…………-1.22
ASOS…………..0.64
TOTAL PRECIPITATION FOR THE YEAR……….43.61   DEPARTURE…………-1.98
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…….0.2     DEPARTURE………….+0.2
TOTAL SNOWFALL FOR THE MONTH………….0.2     DEPARTURE………….-0.2
TOTAL SNOWFALL FOR THE SEASON…………0.2     DEPARTURE………….-0.5

PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER 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

11/1  68/56/62/+16/0.10/0.0/012/02        60 SSW AERO N/A N/A    RMY 66
11/2  65/49/57/+11/0.00/0.0/296/48        22 WSW AERO N/A N/A    RMY 23
11/3  49/30/40/-6/0.06/T/135/22           23 N   AERO N/A N/A    RMY N/A
11/4  42/27/35/-10/0.00/0.0/588/96        24 NNE AERO N/A N/A    RMY 25
11/5  50/29/40/-5/0.00/0.0/487/80         16 SSW AERO N/A N/A    RMY 17
11/6  59/40/50/+5/0.00/0.0/419/69         30 SSW AERO 31 MPH SSW RMY 33
11/7  65/37/51/+6/0.31/0.0/079/13         33 SW  AERO 37 MPH SW  RMY 37
11/8  48/31/40/-4/T/T/0.0/421/70          37 WNW AERO 37 MPH WNW RMY 39
11/9  44/29/37/-7/0.00/0.0/361/66         25 WNW AERO 25 MPH WNW RMY 29
11/10 52/40/46/+2/0.08/0.0/108/18         31 WNW AERO 33 MPH WNW RMY N/A
11/11 51/36/44/+1/0.00/0.0/…/..         36 WNW AERO 37 MPH WNW RMY 37
11/12 48/24/36/-7/0.11/0.2/000/00         42 SW  AERO 43 MPH SW  RMY 43

11/13 morning low temp: 21F; the normal low is now 34F

DAILY RECORDS FOR NOVEMBER 2013
None so far.

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

RECORDS FOR NOVEMBER 13
HIGH 66 IN 1931, 1964
LOW 14 IN 1920
PRECIP 1.96 INCHES IN 1982
SNOWFALL 4.6 IN 2004
PEAK GUST 77 S IN 1982

RECORDS FOR NOVEMBER 14
HIGH 70 IN 1993
LOW 11 IN 1905
PRECIP 2.08 INCHES IN 2009
SNOWFALL 3.5 IN 1997
PEAK GUST 63 W IN 2003

TODAY’S REPORT PREPARED BY: Robert Skilling