Sunday, January 18, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, JANUARY 18, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

WARMING TEMPERATURES TODAY WITH RAIN ON THE WAY

The temperature took on an unusual trend last night here at Blue Hill,
with the mercury bottoming out at 17F for several hours last evening,
before rising through the pre-dawn hours this morning.  By 7:00 A.M. we
were already up to 32F at the summit, and we have climbed to 50F by 1:00
this afternoon, only the second time this month we’ve climbed that high.
This mild air is associated with an approaching storm system that will
deliver some rainfall later today and tonight.  A few very light showers
began by mid-morning, but through early afternoon the steadier rain is still
holding off.  Winds have also been active today, with a peak gust of 41mph
so far and an average speed of 15-20mph.  The direction has been mainly out
of the S to SSE.

Today’s Observations:

7 A.M.
Weather: Broken stratocumulus, overcast altocumulus, few lower
stratocumulus and stratus fractus, break in overcast N
Temperature: 32F; Dew Point: 28F; Wind: S at 16 kts
Sea-level pressure: 30.17 ins. Hg, falling then falling more rapidly
Visibility: 30 miles, distant haze
6-hr max temp: 32F
6-hr min temp: 21F
Snow Depth: Trace
BHO SA 1155 E40 BKN 80 OVC 30 218/32/28/1816/017/ FEW LWR SC AND STFRA
BINOVC N DSNT HZ/ 8/570 58018 10032 20021

10 A.M.
Weather: Broken stratocumulus, overcast nimbostratus, few stratus fractus,
light rain shower began 9:50 A.M., precipitation very light
Temperature: 40F; Dew Point: 39F; Wind: SSE at 16G22 kts
Sea-level pressure: 30.11 ins. Hg, falling then falling more rapidly
Visibility: 20 miles
3-hr precip: Trace
BHO SA 1455 E35 BKN 45 OVC 20R- 198/40/39/1516G22/011/ FEW STFRA RW-B50
PCPN VRY LGT/ 8/52/ 58020 MANUAL 6000/

1 P.M.
Weather: Broken stratocumulus, overcast nimbostratus, rain showers distant
SW-NW
Temperature: 50F; Dew Point: 44F; Wind: SSE at 22G31 kts,
Wind: Peak wind of 31 kts SSE at 12:52 P.M.
Sea-level pressure: 29.98 ins. Hg, falling then falling more slowly
Visibility: 30 miles
6-hr max temp: 50F
6-hr min temp: 32F
6-hr precip: Trace
BHO SA 1755 E25 BKN 45 OVC 30 153/50/44/1622G31/998/ SHRA DSNT SW-NW
PK WND 1731/52 8/57/ 56045 MANUAL 6000/ 10050 20032

SUMMARY FOR SATURDAY, JANUARY 17, 2015

TEMPERATURE (DEGREES F)
MAX…..21   NORMAL…..33
MIN……5   NORMAL…..17
MEAN….13   NORMAL…..25

DEPARTURE FROM 30-YEAR NORMAL…………………….-12
TOTAL DEPARTURE FOR THE MONTH…………………….-55 [-3.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..52  DEPARTURE……….+12
TOTAL HEATING UNITS FOR THE MONTH………….724  DEPARTURE……….+56
TOTAL HEATING UNITS FOR THE SEASON………..2784  DEPARTURE………-188
TOTAL HEATING UNITS LAST SEASON TO DATE……2899  DIFFERENCE……..-115

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………30  WNW  AT  1:05 A.M.
ASOS…………………..32  WNW  AT  1:05 A.M.
DAVIS………………….31  WNW  AT  1:04 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………..23  WNW  AT  1:07 A.M. *
MAXIMUM 2-MINUTE ASOS AVERAGE……………..23  WNW  AT  1:05 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….22  WNW  AT  1:05 A.M.
AVERAGE WIND SPEED AND DIRECTION…………11.6  WNW
ASOS…………………11.7
DAVIS………………..10.2  W [260 degrees] * last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE…..-0.15
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.58  DEPARTURE…..-0.85
ASOS…………..1.60
TOTAL PRECIPITATION FOR THE YEAR………..1.58  DEPARTURE…..-0.85
ASOS…………..1.60

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……-0.6
TOTAL SNOWFALL FOR THE MONTH…………….4.9  DEPARTURE……-4.7
TOTAL SNOWFALL FOR THE SEASON…………..15.9  DEPARTURE……-9.7

PRELIMINARY CLIMATE SUMMARY FOR JANUARY 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

1/1  31/18/25/-2/0.00/0.0/544/99              29 SSW RMY 30
1/2  37/26/32/+5/0.00/0.0/314/57              35 WSW RMY 38
1/3  34/21/28/+2/0.67/2.5/017/03              25 SE  RMY 26
1/4  51/33/42/+16/0.48/0.0/000/00             30 SSW RMY N/A
1/5  46/13/30/+4/0.00/0.0/542/98              48 W   RMY 54
1/6  15/10/13/-13/0.02/0.4/000/00             29 W   RMY N/A
1/7  22/01/12/-14/0.01/0.3/394/71             43 WNW RMY 47
1/8  16/-5/6/-20/0.00/0.0/539/97              39 WNW RMY N/A
1/9  27/16/22/-4/0.08/0.9/…/..              35 WSW RMY 38
1/10 22/11/17/-8/0.00/0.0/541/97              26 WNW RMY 27
1/11 31/9/20/-5/45/0.00/0.0/123/22            26 SSW RMY N/A
1/12 36/31/34/+9/0.23/T/000/00                29 NNW RMY N/A
1/13 33/11/22/-3/0.00/0.0/524/93              30 NNW RMY 29
1/14 22/11/17/-8/T/T/000/00                   18 NNW RMY 16
1/15 27/20/24/-1/0.09/0.8/000/00              20 WSW RMY 22
1/16 35/12/24/-1/T/T/…/..                   46 WSW RMY 50
1/17 21/5/13/-12/0.00/0.0/…/..              30 WNW RMY N/A

1/18 morning low temp: 19F since midnight; normal low is now 17F

DAILY RECORDS FOR JANUARY 2015
None so far.

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

RECORDS FOR JANUARY 18
HIGH 62F IN 1973,1990
LOW -10F IN 1982
PRECIP 1.68 INS. IN 1915
SNOWFALL 13.0 INS. IN 1948
PEAK GUST 85 MPH SSE IN 2006

RECORDS FOR JANUARY 19
HIGH 59F IN 1973
LOW -11F IN 1887
PRECIP 2.34 INS. IN 1936
SNOWFALL 10.5 INS. IN 1936
PEAK GUST 93e MPH WNW IN 1943

TODAY’S REPORT PREPARED BY: Jonathan O’Brien