Thursday, December 17, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, DECEMBER 17, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

TEMPS DROP TO 30S AND 40S ON WEDNESDAY,
TEMPS STILL WARMER THAN NORMAL WITH RAIN ON THE WAY

Yesterday’s maximum temperature of 45F was reached at midnight
yesterday morning as cooler air worked into the region.
Temperatures struggled to a daytime high of 43F and dropped
into the 30s after sundown. With a mean temperature of 40F,
temperatures were still 9 degrees warmer than normal.

Drizzle began this morning at approximately 7:45 AM EST
with foggy conditions. Winds had become gusty from the SE,
gusting near 30 MPH by mid morning.

By the 1:00 PM EST observation drizzle had temporarily
stopped; however, fog had grown thicker with visibility
of just 1/4 of a mile. A maximum temperature of 48F had
been recorded so far.

BHO Warmest NWS Mean Temperature, December 1st-15th, deg F (1885-2015):

1) 45.4 in 2015
2) 44.0 in 2001
3) 43.5 in 1998
4) 43.3 in 1953
5) 40.7 in 2011

BHO Warmest Average Maximum Temperature, December 1st-15th, deg F (1885-2015):

1) 52.6 in 2015
2) 51.4 in 1953
3) 51.3 in 1998
4) 50.7 in 2001
5) 48.8 in 1891

BHO Warmest Average Minimum Temperature, December 1st-15th, deg F (1885-2015):

1) 38.2 in 2015
2) 37.2 in 2001
3) 35.6 in 1998
4) 35.1 in 1953
5) 33.7 in 1999

Today’s Observations:

7 A.M.
Weather: Broken stratocumulus, overcast altostratus,
breaks in overcast E-ESE
Temperature: 39F; Dew Point: 38F; Wind: SE at 14G22 kts
Sea-level pressure: 30.09 ins. Hg, rising, then falling and lower
Visibility: 20 miles, except 15 miles SW, thin fog
6-hr Max temp: 39F
6-hr Min temp: 36F
24-hr precip: 0.00 ins
BHO SA 1155 E12 BKN 80 OVC 20 188/39/38/1314G22/009/
VSBY SW 15 MI BINOVC E-ESE THN FG ALQDS/ 8/52/ 58009 10039 20036

10 A.M.
Weather: Light drizzle, fog
Temperature: 43F; Dew Point: 43F; Wind: SE at 16 kts,
Sea-level pressure: 30.07 ins. Hg, falling, then more quickly
Visibility: 3/4 miles, fog and light drizzle
3-hr precip: Trace
BHO SA 1455 W4 X 3/4L-F 182/43/43/1416/007/ 8//// 58006 MANUAL 6000/

1 P.M.
Weather: Thick fog
Temperature: 47F; Dew Point: 47F; Wind: SE at 10 kts,
Sea-level pressure: 29.92 ins. Hg, falling rapidly
Visibility: 1/4 of a mile, thick fog
6-hr max. temp: 48F
6-hr min. temp: 39F
6-hr precip: Trace
BHO SA 1755 W3 X 1/4F 132/47/47/1410/992/
PRESFR/ 8//// 58050 MANUAL 6000/ 10048 20039

SUMMARY FOR WEDNESDAY, DECEMBER 16, 2015

TEMPERATURE (DEGREES F)
MAX…..45   NORMAL…..39
MIN…..34   NORMAL…..24
MEAN….40   NORMAL…..31

DEPARTURE FROM 30-YEAR NORMAL………………….+9
TOTAL DEPARTURE FOR THE MONTH………………..+182  [+11.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..25   DEPARTURE……….-9
TOTAL HEATING UNITS FOR THE MONTH………….316   DEPARTURE……..-183
TOTAL HEATING UNITS FOR THE SEASON………..1318   DEPARTURE……..-443
TOTAL HEATING UNITS LAST SEASON TO DATE……1634   DIFFERENCE…….-316

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….25 N   AT  2:22 A.M.
ASOS……………………27 N   AT  2:32 A.M.
DAVIS…………………..26 NNW AT  2:21 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………17 N   AT  2:22 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………17 NNW AT  2:33 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..16 N   AT  2:21 A.M.
AVERAGE WIND SPEED AND DIRECTION…………..9.3 N
ASOS…………………..9.3
DAVIS………………….8.2 ENE [066 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………..1.00  DEPARTURE……-1.62
ASOS……………1.01
TOTAL PRECIPITATION FOR THE YEAR………..40.42  DEPARTURE…..-10.74
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……-0.5
TOTAL SNOWFALL FOR THE MONTH…………….0.0  DEPARTURE……-5.8
TOTAL SNOWFALL FOR THE SEASON………….TRACE  DEPARTURE……-8.4

PRELIMINARY CLIMATE SUMMARY FOR 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

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/…./0.0/162/29           43 WNW RMY 42
12/4  47/32/40/+5/0.00/0.0/444/80           32 NW  RMY 32
12/5  50/33/42/+7/0.00/0.0/548/99           21 W   RMY N/A
12/6  57/35/46/+11/0.00/0.0/531/96          22 SW  RMY N/A
12/7  54/37/46/+12/0.00/0.0/353/64          31 NE  RMY N/A
12/8  42/35/39/+5/0.01/0.0/000/00           32 NE  RMY 31
12/9  44/34/39/+5/…./0.0/044/08           28 SSE RMY N/A
12/10 57/41/49/+16/T/0.0/…/..             29 SE  RMY N/A
12/11 56/44/50/+17/0.00/0.0/…/..          28 SSW RMY 28
12/12 59/46/53/+20/0.00/0.0/…/..          23 W   RMY N/A
12/13 54/44/49/+17/0.00/0.0/…/..          18 ESE RMY 19
12/14 60/43/52/+20/…./0.0/000/00          32 S   RMY N/A
12/15 61/45/53/+21/…./0.0/…/..          48 W   RMY 51
12/16 45/34/40/+9/0.00/0.0/…/..           25 N   RMY N/A

12/17 since midnight is 36F; normal low is now 23F

DAILY RECORDS FOR DECEMBER 2015

**12/13/2015- NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 44F,
BREAKS PREVIOUS RECORD OF 43F SET IN 1919, TIED 1983**

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

RECORDS FOR DECEMBER 17
HIGH 63 IN 2000
LOW -10 IN 1942
PRECIP 3.03 INS. IN 1888
SNOWFALL 7.5 INS. IN 1988
PEAK GUST 78 MPH SSE IN 2000

RECORDS FOR DECEMBER 18
HIGH 59 IN 1928
LOW -11 IN 1919
PRECIP 1.44 INS. IN 1915
SNOWFALL 7.0 INS. IN 1904
PEAK GUST 76e W IN 1978

TODAY’S REPORT PREPARED BY: Brian Fitzgerald