Friday, December 5, 2014

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, DECEMBER 5, 2014
ALL TIMES ARE IN EASTERN STANDARD TIME

AIR MASS BECOMING MUCH MORE MOIST WITH RISING DEW POINTS
SUNSHINE PREVAILS AND TEMPS. RISE TO 40 DEGREES

The air mass was moistening up today as indicated by the
rising dew point from 12 degrees early this morning to the
mid-upper 20’s by this afternoon. Low clouds from off the
ocean have scattered across the sky and an invading cirrostratus
layer in the distant S-WSW could been seen slowly invading
early this afternoon.

NOVEMBER 2014 PRELIMINARY STATS
[Departures are relative to the 1981-2010 normal]

TEMPERATURE [deg. F]

Av. Max. 48.0 [-2.0] Av. Min. 32.2 [-1.3] Mean     40.1 [-1.6] 24-hour corr. mean: 40.3
Max. temp. for month: 66 on 5th
Min, temp. for month: 17 on 29th
Total heating degree day units: 737 [+39] Total seasonal heating   units: 1159 [-102]

PRECIPITATION [ins.] Total: 6.21 [+1.45] Greatest one calendar day: 1.77 [26th] Greatest in 24 hours: 1.81 [26-27th] Snow: 8.7 [+6.4] Total Season Snow: 8.7 [+6.1] Greatest one calendar day: 3.5 [14th] Greatest in 24 hours: 3.5 [13-14th]

WIND
Av. wind speed:       13.1 MPH
Av. corr. wind speed: 13.4 MPH
Prevailing direction: W @ 15%

SUNSHINE
Total astronomical minutes: 8114 of 17626 possible, or 46%
Total Campbell Stokes card minutes: 7818 of 17010 possible, or 46%

Today’s Observations:

7 A.M.
Weather: Clear, cumulus, stratocumulus along and offshore NNE-E
altocumulus along horizon distant SE-SSW
Temperature: 23F; Dew Point: 12F; Wind: N at 10 kts
Sea-level pressure: 30.63 ins. Hg, rising then more slowly
Visibility: 40 miles, except NE 20 miles hazy,
WNW 55 miles light distant haze
6-hr max temp: 26F
6-hr min temp: 23F
24-hr precip: 0.00 in.
BHO SA 1155 CLR 40 372/23/12/3610/063/ CU/SC ALG/OFFSHR NNE-E
AC ALG HRZN DSNT SE-SSW VSBY NE 20 HAZY WNW 55 DSNT HZ/
8/830 51007 10026 20023

10 A.M.
Weather: Clear, stratocumulus layer N-ESE, patch of
altocumulus/lenticularis SE-SW, few cirrus N-NE
Temperature: 32F; Dew Point: 21F; Wind: NNE at 6 kts
Sea-level pressure: 30.67 ins. Hg, rising, then falling
Visibility: 30 miles, hazy, 20 miles, N, 15 miles NE,
thin smoke and haze
BHO SA 1455 CLR 30 386/32/21/0306/067/ SC LYR N-ESE
PTCH AC/ACSL SE-SW FEW CI N-NE VSBY N 20 NE 15
THN K HAZY VSBY WNW 45 WND LGT/ 8/541 50014

1 P.M.
Weather: Scattered cumulus/stratocumulus, moderate tops,
scattered altocumulus lenticularis (S-SW, distant,
scattered cirrostratus layer S-WSW, invading, scattered cirrus
Temperature: 40F; Dew Point: 27F; Wind: ENE at 5 kts,
Wind: Light
Sea-level pressure: 30.60 ins. Hg, falling then more slowly
Visibility: 40 miles, distant haze, NE 30 miles, hazy
6-hr max temp: 40F
6-hr min temp: 23F
BHO SA 1755 25 SCT 30 SCT 180 SCT 250 SCT 300 –SCT 40 363/40/27/0605/060/
CUSC MDT CUFRM TOPS FEW ACSL DSNT S-SW CS LYR DSNT S-WSW INVDNG FEW CI
VSBY NE 30 HZY DSNT HZ ALQDS WND LGT/ 8/845 56023 10040 20023

SUMMARY FOR THURSDAY, DECEMBER 4, 2014

TEMPERATURE (DEGREES F)
MAX…..41   NORMAL…..43
MIN…..27   NORMAL…..28
MEAN….34   NORMAL…..35

8DEPARTURE FROM 30-YEAR NORMAL…………………….-1
TOTAL DEPARTURE FOR THE MONTH…………………….+16 [+3.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..31  DEPARTURE………..+1
TOTAL HEATING UNITS FOR THE MONTH………….100  DEPARTURE……….-16
TOTAL HEATING UNITS FOR THE SEASON………..1259  DEPARTURE………-119
TOTAL HEATING UNITS LAST SEASON TO DATE……1335  DIFFERENCE………-76

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………28 WNW AT 12:20 A.M. *
ASOS…………………..32 WNW AT 12:20 A.M.
DAVIS………………….30 W   AT 12:19 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………..22 W   AT 12:06 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..22 W   AT 12:07 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….20 WNW AT 12:20 A.M.
AVERAGE WIND SPEED AND DIRECTION……………11.1 W
ASOS……………………10.8
DAVIS……………………9.7 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……….0.42  DEPARTURE…..-0.23
ASOS…………..0.46
TOTAL PRECIPITATION FOR THE YEAR……….48.18  DEPARTURE…..-1.00
ASOS………….48.65

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……………8.7  DEPARTURE……+5.0

PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER & DECEMBER 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

11/1  45/36/41/-5/0.79/0.0/000/00              35 NNE RMY N/A
11/2  37/32/35/-11/0.29/1.8/000/00             46 NW  RMY 49
11/3  50/30/45/-6/0.00/0.0/584/95              39 WNW RMY 43
11/4  61/44/53/+8/0.00/0.0/208/34              28 SSW RMY 32
11/5  66/50/58/+13/0.00/0.0/006/01             29 SSW RMY N/A
11/6  52/45/49/+4/0.58/0.0/000/00              23 NE  RMY 24
11/7  46/34/40/-5/0.00/0.0/079/13              39 NW  RMY 42
11/8  47/30/39/-5/0.00/0.0/555/92              24 W   RMY 25
11/9  56/38/47/+3/0.00/0.0/204/34              23 SSW RMY N/A
11/10 58/40/49/+5/0.00/0.0/592/99              17 S   RMY 20
11/11 61/43/52/+9/0.00/0.0/358/60              22 S   RMY 25
11/12 59/40/50/+7/0.00/0.0/095/16              22 W   RMY 25
11/13 49/32/41/-2/0.08/T/450/76                21 NW  RMY N/A
11/14 41/27/34/-8/0.29/3.5/442/75              23 NW  RMY 27
11/15 37/24/31/-11/0.00/0.0/569/97             23 NW  RMY 23
11/16 39/26/33/-9/0.00/0.0/012/02              17 S   RMY 19
11/17 52/34/43/+2/1.67/0.0/000/00              29 ENE RMY 31
11/18 44/23/34/-7/0.00/0.0/494/85              33 W   RMY 39
11/19 35/19/27/-14/0.00/0.0/544/94             31 WSW RMY N/A
11/20 47/26/37/-3/0.00/0.0/542/94              35 WSW RMY 41
11/21 34/22/28/-12/0.00/0.0/569/99             31 WNW RMY 39
11/22 43/20/32/-8/0.00/0.0/350/61              32 SW  RMY 36
11/23 58/40/49/+10/0.00/0.0/365/64             26 SW  RMY N/A
11/24 63/43/53/+14/0.60/0.0/000/00             44 S   RMY 53
11/25 61/44/53/+14/0.00/0.0/023/04             28 SW  RMY 30
11/26 44/31/38/+0/1.77/1.0/000/00              41 NE  RMY 46
11/27 36/27/32/-6/0.08/0.9/057/10              29 N   RMY N/A
11/28 32/21/27/-11/0.06/1.5/175/31             29 WNW RMY 32
11/29 32/17/25/-12/0.00/0.0/455/81             17 S   RMY N/A
11/30 55/30/43/+6/0.00/0.0/386/69              32 SSW RMY 38

12/1  63/37/50/+13/0.01/0.0/…/..             28 WNW RMY 31
12/2  37/30/34/-2/…./T/000/00                26 E   RMY 29
12/3  49/34/42/+6/…./0.0/000/00              40 W   RMY 43
12/4  41/27/34/-1/…./0.0/…/..              29 WNW RMY N/A

12/5 morning low temp: 23F since midnight; the normal low is now 27F

DAILY RECORDS FOR DECEMBER 2014:
None so far.

DAILY RECORDS FOR NOVEMBER 2014:
11/2  – A NEW RECORD DAILY SNOWFALL: 1.8 INCHES;
surpasses the previous record of 0.2 ins. in 1906, 1951
11/14 – DAILY SNOWFALL RECORD EQUALED: 3.5 INCHES;
ties previous record on this date in 1997

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