Monday, December 7, 2015
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, DECEMBER 7, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME
INVERSION TRAPS HAZE AND FOG BENEATH THE SUMMIT
TODAY- WARM STRETCH CONTINUES
Warm temperatures on Sunday continued a five day streak
of warmer than normal temperatures. Yesterday’s maximum
temperature was 57F, some 15 degrees above the daily normal
maximum. Temperatures through yesterday now are averaging
6.5 degrees F above normal to start the month.
A thermal inversion was present once again this morning,
trapping cold air, thin fog and haze below the summit at
the height of approximately 500 feet.
By today’s 1:00 PM EST observation the inversion that was
present for most of this morning had lifted above the height
of Great Blue Hill and the tallest buildings of downtown
Boston. Visibility was still marginal at 30-40 miles in
all directions due to hazy conditions. A maximum temperature
of 54F had been recorded so far.
BHO Warmest Novembers, deg F (1885-2015):
1) 47.9 in 2011
2) 47.4 in 1975
3) 47.1 in 2006
4) 46.4 in 1948
46.4 in 1979
46.4 in 2009
7) 46.1 in 2015
8) 46.0 in 2001
9) 45.7 in 1953
45.7 in 1999
BHO Highest November Sea-Level Pressure, inches (1885-2015):
1) 30.88 in 1932
30.88 in 2015
3) 30.86 in 1887
4) 30.83 in 1896
5) 30.82 in 1891
6) 30.80 in 1996
7) 30.79 in 2013
8) 30.77 in 1914
PRELIMINARY STATS FOR NOVEMBER 2015
TEMPERATURE, Deg. F
Avg. Max. 54.3 [+4.3]
Avg. Min. 38.6 [+5.1]
Mean 46.5 [+4.8]
Corrected mean: 46.1
Max. for month: 72 on 5th
Min. for month: 23 on 24th
COOLING DEGREE DAYS
Total cooling units: 1 [+1]
Total for the season: 811 [+209]
Total for last season: 595
HEATING DEGREE DAYS
Total heating units: 548 [-150]
Total for the season: 1002 [-259]
Total for last season: 1159
PRECIPITATION, Inches
Total: 2.59 [-2.17]
Greatest in 24 hrs: 1.18 from 20th
Snowfall: Trace [-2.3]
Seasonal: Trace [-2.6]
WIND, mph
Avg. uncorrected wind speed: 12.4
Avg. corrected wind speed: 12.7
Prevailing wind direction: W @ 13%
Peak gust and direction: 43 SSE on the 20th
SUNSHINE:
Campbell-Stokes card minutes: 9222/17010 or 54%
Astronomical total minutes: 9562/17644 or 54%
Today’s Observations:
7 A.M.
Weather: Thin broken cirrostratus, inversion present
with estimated top height of 500 feet over the city,
thin fog and smoke layer below the inversion.
Temperature: 36F; Dew Point: 34F; Wind: WSW at 9 kts
Sea-level pressure: 30.13 ins. Hg, falling then more slowly
Visibility: 15 miles, Mount Wachusett visible over inversion
6-hr Max temp: 40F
6-hr Min temp: 36F
24-hr precip: 0.00
BHO SA 1155 E250 -BKN 15 204/36/34/2409/013/ INVSN PRSNT ESTMD
TOP 5 HND OVR CTY THN FG AND K LYR BLO INVSN/ 8/008 56004 10040
20036
10 A.M.
Weather: Thin broken cirrostratus, inversion present
with estimated top height of 500 feet over the city,
hazy below inversion
Temperature: 40F; Dew Point: 33F; Wind: WSW at 7 kts,
Sea-level pressure: 30.12 ins. Hg, steady, then falling
Visibility: 15 miles, hazy below inversion
BHO SA 1455 E250 -BKN 15 200/40/33/2507/012/ INVSN PRSNT
ESTMD TOP 5 HND OVR CTY N HAZY BLO INVSN/ 8/008 58004
1 P.M.
Weather: Clear, few cirrus distant NE-SE
Temperature: 54F; Dew Point: 33F; Wind: estimated SSW at 5 kts,
Sea-level pressure: 30.04 ins. Hg, falling, then more quickly
Visibility: 30 miles, except 40 miles WSW-WNW, hazy
6-hr max. temp: 54F
6-hr min. temp: 36F
BHO SA 1755 CLR 30 174/54/33/E2105/004/ VSBY WSW-WNW 40 MI
FEW CI DSNT NE-SE HAZY WND LGT/ 8/001 58026 10054 20036
SUMMARY FOR SUNDAY, DECEMBER 6, 2015
TEMPERATURE (DEGREES F)
MAX…..57 NORMAL…..42
MIN…..35 NORMAL…..27
MEAN….46 NORMAL…..35
DEPARTURE FROM 30-YEAR NORMAL…………………+11
TOTAL DEPARTURE FOR THE MONTH…………………+40 [+6.5 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..19 DEPARTURE………-11
TOTAL HEATING UNITS FOR THE MONTH………….136 DEPARTURE………-41
TOTAL HEATING UNITS FOR THE SEASON………..1138 DEPARTURE……..-300
TOTAL HEATING UNITS LAST SEASON TO DATE……1316 DIFFERENCE…….-178
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….22 SW AT 9:52 P.M.
ASOS……………………20 SW AT 10:06 P.M.
DAVIS…………………..19 SW AT 9:29 P.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………16 SW AT 10:14 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………16 SW AT 10:17 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..16 SW AT 9:30 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..11.9 SW
ASOS…………………..12.1
DAVIS………………….10.9 SW [233 Deg.]
* 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………..0.37 DEPARTURE……-0.61
ASOS……………0.36
TOTAL PRECIPITATION FOR THE YEAR………..39.79 DEPARTURE……-9.73
ASOS…………….N/A ***
*** ASOS annual total not available due to erroneous readings
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0 DEPARTURE……-0.3
TOTAL SNOWFALL FOR THE MONTH…………….0.0 DEPARTURE……-1.7
TOTAL SNOWFALL FOR THE SEASON………….TRACE DEPARTURE……-4.3
PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER & DECEMBER CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/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 59/45/52/+6/T/006/01 30 SSW RMY 31
11/2 62/47/55/+9/0.00/476/77 24 W RMY N/A
11/3 71/44/58/+12/0.00/616/100 25 W RMY 25
11/4 66/49/58/+13/0.00/601/98 22 SSW RMY N/A
11/5 72/51/62/+17/0.00/281/46 31 SW RMY 36
11/6 71/60/66/+21/0.00/109/18 35 SSW RMY 38
11/7 64/46/55/+10/0.00/029/04 33 WNW RMY 35
11/8 54/39/47/+3/0.00/591/98 26 NW RMY 30
11/9 59/38/49/+5/0.00/577/96 20 W RMY 21
11/10 53/45/49/+5/0.11/000/00 28 NE RMY N/A
11/11 48/43/46/+3/0.60/000/00 41 NE RMY N/A
11/12 55/42/49/+6/0.07/000/00 28 S RMY 30
11/13 57/41/49/+6/0.02/385/65 40 WSW RMY 47
11/14 45/31/38/-4/0.00/425/72 40 NW RMY 47
11/15 51/31/41/-1/0.00/241/41 25 W RMY 27
11/16 59/36/48/+6/0.00/416/71 25 NNW RMY 29
11/17 45/28/37/-4/0.00/572/98 18 NNE RMY N/A
11/18 50/35/43/+2/0.00/575/99 17 SSE RMY N/A
11/19 55/38/47/+6/T/000/00 29 SSE RMY N/A
11/20 58/41/50/+10/1.18/416/72 43 SSE RMY N/A
11/21 46/35/41/+1/0.00/380/66 20 ENE RMY 21
11/22 45/35/40/+0/0.40/000/00 26 NW RMY 28
11/23 40/25/33/-6/0.02/543/95 24 NW RMY 29
11/24 42/23/33/-6/0.00/564/99 20 WSW RMY 19
11/25 46/31/39/+0/0.00/568/100 18 SSE RMY N/A
11/26 58/37/48/+10/0.00/386/68 33 S RMY 35
11/27 63/48/54/+18/0.00/249/44 35 SW RMY 38
11/28 55/38/47/+9/0.19/000/00 23 SW RMY N/A
11/29 42/28/35/-2/0.00/410/73 17 NNW RMY 21
11/30 37/27/32/-5/T/T/151/27 17 S RMY 18
12/1 42/30/36/-1/…./0.0/000/00 19 NNE RMY 19
12/2 53/37/45/+9/…./0.0/000/00 25 SSE RMY 25
12/3 53/37/45/+9/…./0.0/…/.. 43 WNW RMY 42
12/4 47/32/40/+5/0.00/0.0/…/.. 32 NW RMY 32
12/5 50/33/42/+7/0.00/0.0/…/.. 21 W RMY N/A
12/6 57/35/46/+11/0.00/0.0/…/.. 22 SW RMY N/A
12/7 low since midnight is 36F; normal low is now 27F
DAILY RECORDS FOR NOVEMBER AND DECEMBER 2015
**11/6 DAILY RECORD MAXIMUM TEMPERATURE OF 71F
TIES PREVIOUS RECORD OF 71F SET IN 1959
**11/6 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 60F
BREAKS PREVIOUS RECORD OF 58F SET IN 1938
**11/6 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 60F
TIES PREVIOUS MONTHLY RECORD OF 60F SET ON
11/8/1996
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
RECORDS FOR DECEMBER 7
HIGH 74 IN 1998
LOW 6 IN 1906
PRECIP 1.67 INS. IN 1953
SNOWFALL 6.3 INS. IN 2003
PEAK GUST 76e SE IN 1976
RECORDS FOR DECEMBER 8
HIGH 62 IN 1966
LOW -4 IN 1906
PRECIP 1.54 INS. IN 1969
SNOWFALL 2.5 INS. IN 2001
PEAK GUST 78e W IN 1979
TODAY’S REPORT PREPARED BY: Brian Fitzgerald
