Thursday, December 5, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, DECEMBER 5, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

LOW OVERCAST WITH STRATUS CLOUDS TODAY
BRIEF LIGHT RAIN SHOWER LATE MORNING

A low overcast of stratus clouds has prevented any sunshine
today as temperatures warm through the 40’s ahead of an
approaching warm front. A brief light rain shower left 0.01
inch around 11 A.M.

November, overall, ended up being a cool and relatively dry month compared
to the 30-year normals.  Statistics can be found below.

Meteorological autumn came to a close at the end of November.  The mean
temperature for the September through November period was 51.7F, which was
slightly warmer (+0.7F) than the 120-year mean, and slightly cooler (-0.2F)
than the 30-year mean.  It has been a while since there has been a
whole season below the 30-year normal.  It appears as though winter
2010-2011 was the last time a season finished below the 30-year normal.
The autumn precipitation of 8.59 inches was the 20th driest on record.

For the Jan 1 through Nov 30 period, the mean temperature is tied for 13th
warmest on record.  This year cannot make it into the top ten warmest
unless December has better than record warmth.  The average wind speed for
the Jan 1 through Nov 30 period of 12.2 is tied for second slowest.

NOVEMBER 2013 PRELIMINARY STATISTICS:
(departures relative to 1981-2010 average)

TEMPERATURE:
Average Max Temp: 48.4F [-1.6F] Average Min Temp: 31.2F [-2.3F] Mean Temp: 39.8F [-1.9F] 24-hr. Corr. Mean Temp: 39.7F [-2.4F] Max Temp: 68F on 1st
Min Temp: 14F on 25th

Total heating degree day units (month):    747 [+49] *NCDC method
Total heating degree day units (season): 1,224 [-37] *start July 1 (NCDC)

PRECIPITATION:
Total precipitation: 3.59 inches [-1.17 inch] Greatest 24-hr precipitation: 2.31 inches on 26th and 27th
Total snowfall: 0.2 inch [-2.1 inches]

WIND:
Avg wind speed: 13.6 MPH
Avg corrected wind speed: 13.9 MPH
Prevailing wind direction: WNW [18%] Peak gust: 63 MPH SSE on 27th
Peak fastest mile: 49 MPH SSE on 7th

SUNSHINE:
Total astronomical minutes: 10,313 of possible 17,650 or 58%
Total Campbell Stokes card minutes; 9,966 of possible 17,010 or 59%
* Long term November average is 47%

BHO Highest November Sea Level Pressure on Record, inches (1885-1895, 1942-present)
1. 30.86 in 1887
2. 30.82 in 1891
3. 30.80 in 1996
4. 30.79 in 2013
5. 30.75 in 1888
30.75 in 1993
7. 30.73 in 1986

BHO Greatest November Sunshine, hours (1885-2013)
1) 182.3 in 1939
2) 181.5 in 1917
181.5 in 1976
4) 173.9 in 1905
5) 171.3 in 1964
6) 170.8 in 1941
7) 169.6 in 2011
8) 169.4 in 1975
9) 166.5 in 1994
10) 166.1 in 2013
11) 161.4 in 1965

BHO Greatest Sep-Nov Sunshine, hours (1885-2013)
1) 623.3 in 2001     (63%)
2) 610.7 in 1941     (62%)
3) 605.1 in 1973     (62%)
4) 599.4 in 1966     (61%)
5) 594.5 in 1952     (60%)
6) 592.4 in 1916     (60%)
7) 590.0 in 1978     (60%)
8) 587.8 in 2013     (60%)
9) 587.6 in 1967     (60%)

Today’s Observations:

7 A.M.
Weather: Overcast stratus, thin fog
Temperature: 40F; Dew Point: 32F; Wind: ESE at 13 kts.
Sea-level pressure: 30.18 ins. Hg, falling slightly
Visibility: 12 mileS, thin fog
6-hr min temp: 38F
24-hr precip:  None
BHO SA 1155 E27 OVC 12 219/40/32/1213/018/ THN F ALQDS/
8/6 58003 10040 20038

10 A.M.
Weather: Overcast stratus, thin fog and hazy
Temperature: 44F; Dew Point: 39F; Wind: SE at 12 kts.
Sea-level pressure: 30.16 ins. Hg, falling slightly
Visibility: 15 miles, S-SW 20 miles
BHO SA 1455 E20 OVC 15 213/44/39/1312/016/ VSBY S-SW 20
THN F HAZY ALQDS 8/6// 58006

1 P.M.
Weather: Overcast stratus, thin fog
Temperature: 47F; Dew Point: 45F; Wind: SSE at 9 kts,
Sea-level pressure: 30.07 ins. Hg, falling then more rapidly
Visibility: 6 miles, except 8 miles SW, thin fog
6-hr. max temp. 47F
6-hr precip:  0.01 in.
BHO SA 1755 E7 OVC 6F 186/47/45/1509/007/ VSBY SW 8 THN F/
8/6// 58027 MANUAL 6001/ ASOS 60001 10047 20040

WEATHER SUMMARY FOR WEDNESDAY, DECEMBER 4, 2013

TEMPERATURE (DEGREES F)
MAX…..43    NORMAL…..43
MIN…..29    NORMAL…..28
MEAN….36    NORMAL…..35

DEPARTURE FROM 30-YEAR NORMAL………………….+1
TOTAL DEPARTURE FOR THE MONTH………………….+5 [+1.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..29  DEPARTURE………-1
TOTAL HEATING UNITS FOR THE MONTH………….111  DEPARTURE………-5
TOTAL HEATING UNITS FOR THE SEASON………..1335  DEPARTURE……..-43
TOTAL HEATING UNITS LAST SEASON TO DATE……1240  DIFFERENCE…….+95

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………21 WNW AT  7:50 A.M.
AERO…………………..21 WNW AT  7:50 A.M.
ASOS…………………..21 WNW AT  7:51 A.M.
DAVIS………………….21 W   AT  7:49 A.M. RMY 21
FASTEST MILE FOR YESTERDAY………………..14 WNW AT  7:54 A.M. *
MAXIMUM 2-MINUTE ASOS AVERAGE……………..15 WNW AT  7:53 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….16 WNW AT  6:45 A.M.
AVERAGE WIND SPEED AND DIRECTION………….8.3 WNW
ASOS………………….8.4
DAVIS…………………7.5 WNW [290 degrees] * last of several occurrences…

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……….0.28  DEPARTURE………….-0.37
ASOS…………..0.28
TOTAL PRECIPITATION FOR THE YEAR……….46.88  DEPARTURE………….-2.30
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…….0.0     DEPARTURE………….-0.3
TOTAL SNOWFALL FOR THE MONTH………..Trace     DEPARTURE………….-1.1
TOTAL SNOWFALL FOR THE SEASON…………0.2     DEPARTURE………….-3.5

PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER & 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

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/-7/0.00/0.0/366/61         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/+1/0.00/0.0/500/84         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 35/21/28/-15/0.00/0.0/591/100       29 NW  AERO 30 MPH NW  RMY 30
11/14 49/26/38/-4/0.00/0.0/536/91         25 SW  AERO 25 MPH SW  RMY 28
11/15 59/38/49/+7/0.00/0.0/393/67         24 S   AERO 25 MPH S   RMY 26
11/16 59/40/50/+8/0.00/0.0/363/62         20 WSW AERO 20 MPH WSW RMY N/A
11/17 59/42/51/+10/0.07/0.0/000/00        23 SSE AERO 25 MPH SSE RMY N/A
11/18 65/46/56/+15/0.28/0.0/400/69        40 SSW AERO 40 MPH S   RMY N/A
11/19 46/28/37/-4/0.00/0.0/428/74         46 WNW AERO 46 MPH WNW RMY 46
11/20 40/25/33/-7/0.00/0.0/565/98         23 NW  AERO 22 MPH NW  RMY 22
11/21 46/26/36/-4/0.00/0.0/460/80         16 SW  AERO 16 MPH SW  RMY N/A
11/22 46/39/43/+3/0.22/0.0/000/00         17 WSW AERO 18 MPH SW  RMY 19
11/23 46/27/37/-2/0.00/0.0/451/79         40 WNW AERO 44 MPH WNW RMY 48
11/24 27/17/22/-17/0.00/0.0/552/97        53 NW  AERO 59 MPH NW  RMY 57
11/25 32/14/23/-16/0.00/0.0/568/100       29 W   AERO 29 MPH WNW RMY N/A
11/26 42/29/36/-2/0.13/T/000/00           25 SW  AERO 27 MPH SW  RMY 28
11/27 61/34/48/+10/2.23/0.0/000/00        63 SSE AERO 68 MPH SSE RMY 67
11/28 35/21/28/-10/0.00/0.0/557/99        43 W   AERO 46 MPH W   RMY 45
11/29 33/19/26/-11/0.00/0.0/527/94        23 NNW AERO 23 MPH NNW RMY 24
11/30 32/15/24/-13/0.00/0.0/510/91        18 SE  AERO 19 MPH SE  RMY N/A

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 N/A
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  morning low temp: 38F; the normal low is now 27F

DAILY RECORDS FOR NOVEMBER 2013
11/27 – NEW RECORD MAXIMUM DAILY PRECIPITATION OF 2.23 INCHES;
surpasses the previous record of 1.92 inches in 1898

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 5
HIGH 65 IN 2001
LOW -1 IN 1926
PRECIP 2.86 INS. IN 1993
SNOWFALL 7.0 INS. IN 1926, 1981
PEAK GUST 67 MPH WNW IN 1961, S IN 1973

RECORDS FOR DECEMBER 6
HIGH 70 IN 2001
LOW 5 IN 1901,1935
PRECIP 2.78 INS. IN 2003
SNOWFALL 17.0 INS. IN 2003
PEAK GUST 74 MPH NW IN 1981

TODAY’S REPORT PREPARED BY: Robert Skilling