Tuesday, December 17, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, DECEMBER 17, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

VERY COLD MORNING
INCREASING CLOUDINESS AHEAD OF WINTER STORM

This morning was very cold and clear. It was actually a very
beautiful morning at the summit with a full moon and good
visibility for a winter day. The morning low was 7 degrees.
This continues our December trend of being below normal. As
of yesterday we are averaging about 3.2 degrees F below
average. Later in the morning, the observatory had increasing
cloudiness from the southwest, which is out ahead of some snow
that was being reported at New York City.

Around 11:45 AM the snow started in the Blue Hills area, and the
visibility dropped to about 1/2 mile.

Today’s Observations:

7 A.M.
Weather: Clear, few cumulus, few Cirrus distant S-SW-W.
Temperature: 7F; Dew Point: 1F; Wind: N at 8 kts,
Sea-level pressure: 30.18 ins. Hg, steady
Visibility: 40 miles, light distant haze
6-hr. min temp: 7F
24-hr snowfall: none
Snow depth: 7 inches
BHO SA 1155 CLR 40 222/7/1/3508/018/ FEW CU NE-E FEW CI
S-SW-W/ 8/000 4/007 51005 100// 20007

10 A.M.
Weather: Stratocumulus, few cumulus E, distant haze/fog
Temperature: 9F; Dew Point: 0F; Wind: NNE at 6 kts,
Sea-level pressure: 30.18 ins. Hg, steady
Visibility: 30 miles, light distant haze
BHO SA 1455 40 OVC 50 30 221/9/0/0306/018/ FEW CU DSNT NE-E-SE
HZ ALL QUADS DSNT F W-NW K-layer NE-E SC ALL QUADS 8/500/ 53001

1 P.M.
Weather: Overcast, light snow
Temperature: 16F; Dew Point: 12F; Wind: NNE at 6 kts
Visibility: 2 miles, light snow
Sea-level pressure: 30.10 ins. Hg, falling
6-hr max. temp. 17F
6-hour precip. 0.05 inches
6-hour snowfall: N/A
BHO SA 1755 E// OVC 2S- 192/16/12/0306/010/ TOTAL NEW SNW
PST 3 HRS /// WND LGT/ 8//// 58029 6005/ 10017 20007

WEATHER SUMMARY FOR MONDAY, DECEMBER 16, 2013

TEMPERATURE (DEGREES F)
MAX…..27    NORMAL…..39
MIN…..14    NORMAL…..24
MEAN….21    NORMAL…..31

DEPARTURE FROM 30-YEAR NORMAL…………………-10
TOTAL DEPARTURE FOR THE MONTH…………………-51 [-3.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..44  DEPARTURE……..+10
TOTAL HEATING UNITS FOR THE MONTH………….549  DEPARTURE……..+30
TOTAL HEATING UNITS FOR THE SEASON………..1773  DEPARTURE……..+12
TOTAL HEATING UNITS LAST SEASON TO DATE……1556  DIFFERENCE……+217

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………36 W  AT  9:11 A.M.
AERO…………………..37 W  AT  9:15 A.M.
ASOS…………………..37 W  AT  9:12 A.M.
DAVIS………………….36 W  AT  9:11 A.M. RMY 36
FASTEST MILE FOR YESTERDAY………………..26 W  AT  3:08 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..25 W  AT  2:57 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….24 W  AT  2:56 P.M.
AVERAGE WIND SPEED AND DIRECTION…………15.3 W
ASOS…………………14.5
DAVIS………………..13.2 W  [270 degrees]

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……….2.72  DEPARTURE………….+0.10
ASOS…………..2.72
TOTAL PRECIPITATION FOR THE YEAR……….49.32  DEPARTURE………….-1.83
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………….-0.5
TOTAL SNOWFALL FOR THE MONTH………….8.6     DEPARTURE………….+2.8
TOTAL SNOWFALL FOR THE SEASON…………8.8     DEPARTURE………….+0.4

PRELIMINARY CLIMATE SUMMARY FOR 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

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 16
12/3  45/32/39/+3/0.00/0.0/284/51         18 NNW AERO 18 MPH NNW RMY 20
12/4  43/29/36/+1/0.00/0.0/389/70         21 WNW AERO 21 MPH WNW RMY 21
12/5  53/38/46/+11/0.02/0.0/000/00        36 S   AERO 40 MPH S   RMY 39
12/6  55/33/44/+9/0.38/T/000/00           25 SSW AERO 28 MPH SSW RMY N/A
12/7  40/26/33/-1/0.12/T/287/52           23 NW  AERO 25 MPH NW  RMY N/A
12/8  30/22/26/-8/T/T/039/07              25 NW  AERO 27 MPH NW  RMY N/A
12/9  41/25/33/-1/0.35/0.6/000/00         28 E   AERO 28 MPH E   RMY 24
12/10 33/21/27/-6/0.14/2.1/000/00         28 W   AERO 28 MPH W   RMY 28
12/11 28/19/24/-9/0.00/0.0/345/63         27 SW  AERO 28 MPH SW  RMY 27
12/12 23/14/19/-14/0.00/0.0/…/..        28 WNW AERO 31 MPH NW  RMY 30
12/13 28/14/21/-11/0.00/0.0/…/..        31 W   AERO 32 MPH W   RMY 33
12/14 28/9/19/-13/…./../000/00          30 E   AERO 26 MPH E   RMY N/A
12/15 36/21/29/-3/…./../…/..          48 NE  AERO 50 MPH NE  RMY 51
12/16 27/14/21/-10/…./../…/..         36 W   AERO 37 MPH W   RMY 36

12/17 morning low temp: 7F; the normal low is now 24F

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 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: Kevin Pecora