Monday, January 26, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, JANUARY 26, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

OCEAN EFFECT SNOW BEGINS 9:00 AM EST THIS MORNING,
GREAT BLUE HILL BRACES FOR IMPENDING BLIZZARD

Following Sunday’s crystal clear skies and exceptional
visibility, clouds moved in overnight, becoming overcast
by sunrise this morning. Visibilities have dropped as well,
with ocean effect snow beginning at 9:03 AM EST, staying
very light.

By the 1:00 PM EST observation light snow that began as
very light flurries had become steadier. 0.1 inches of new
snow had been measured with a liquid equivalent of 0.01 inches
of water. Visibility was reduced to 5 miles in all directions
with humidity increasing and a temperature/dew point of 22F/19F.
Winds were beginning to increase and shift to the NE, gusting
up to 18 knots. A maximum temperature of 22F had been recorded.

Here at BHO, we have cracked open the record books for
the potential comparison to some of the biggest snow
storms observed here. Here are the top five snowstorms
measured here on Great Blue Hill:

1) 38.7 inches on 24-28 Feb, 1969
2) 30.3 inches on 3-5 Mar, 1960
3) 30.1 inches on 6-7 Feb, 1978
4) 30.0 inches on 31 Mar – 1 Apr 1997
5) 29.8 inches 6-8 Mar, 2013

Stay tuned tomorrow for special reports and updates, along
with storm totals so far during the daily discussion.
Today’s Observations:

7 A.M.
Weather: Broken altocumulus, thin overcast of cirrostratus,
few stratocumulus distant offshore NNE-SE
Temperature: 10F; Dew Point: 1F; Wind: N at 7 kts
Sea-level pressure: 30.12 ins. Hg, decreasing then increasing
Visibility: 40 miles
6-hr max temp: 15F
6-hr min temp: 9F
24-hr precip: 0.00 in.
24 hr snowfall: 0 ins.
Total snow on ground: 4 inches
BHO SA 1155 E130 BKN 200 -OVC 40 199/10/1/3607/012/
FEW SC DSNT OFFSHR NNE-SE/ 8/527 4/004 51008 10015 20009

10 A.M.
Weather: Light snow flurries, scattered stratocumulus,
scattered altostratus, thin overcast of cirrostratus
Temperature: 15F; Dew Point: 9F; Wind: N at 8 kts
Sea-level pressure: 30.12 ins. Hg, increasing then more slowly
Visibility: 12 miles, except 20 miles WSW-NNW, obscured by
light snow
3-hr precip: Trace
3-hr snowfall Trace
BHO SA 1455 22 SCT 70 SCT 200 -OVC 12S- 201/15/9/3608/012/
S-B03 VSBY WSW-NNW 20 MI PRCP VRY LGT NEW SNW PST 3 HRS TRACE/
8/527 51002 MANUAL 6000

1 P.M.
Weather: Light snow, overcast stratus
Temperature: 22F; Dew Point: 19F; Wind: NE at 10G18 kts,
Sea-level pressure: 30.05 ins. Hg, increasing, then decreasing quickly
Visibility: 5 miles, obscured by light snow
6-hr max. temp: 22F
6-hr min. temp: 9F
6-hr precip: 0.01
6-hr snowfall: 0.1
BHO SA 1755 E13 OVC 5S- 175/22/19/0410G18/005/
NEW SNW PST 6 HRS 0.1 IN/ 8/6// 58026
ASOS 60001 MANUAL 60001 10022 20009
SUMMARY FOR SUNDAY, JANUARY 25, 2015

TEMPERATURE (DEGREES F)
MAX…..34   NORMAL…..34
MIN…..17   NORMAL…..17
MEAN….26   NORMAL…..25

DEPARTURE FROM 30-YEAR NORMAL……………………..+1
TOTAL DEPARTURE FOR THE MONTH…………………….-16 [-0.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..39  DEPARTURE………..-1
TOTAL HEATING UNITS FOR THE MONTH…………1005  DEPARTURE……….+16
TOTAL HEATING UNITS FOR THE SEASON………..3065  DEPARTURE………-228
TOTAL HEATING UNITS LAST SEASON TO DATE……3256  DIFFERENCE……..-191

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………31 W     AT 11:16 A.M.
ASOS…………………..35 W     AT 11:16 A.M.
DAVIS………………….32 W     AT 11:21 A.M. RMY 33
FASTEST MILE FOR YESTERDAY………………..26 W     AT 11:17 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..25 W     AT 11:17 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….22 W     AT 11:22 A.M.
AVERAGE WIND SPEED AND DIRECTION…………14.2 W
ASOS…………………15.7
DAVIS………………..9.7 W [283 degrees] * last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE…..-0.14
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….2.60  DEPARTURE…..-0.94
ASOS…………..2.67
TOTAL PRECIPITATION FOR THE YEAR………..2.60  DEPARTURE…..-0.94
ASOS…………..2.67

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……-0.6
TOTAL SNOWFALL FOR THE MONTH…………….9.9  DEPARTURE……-4.0
TOTAL SNOWFALL FOR THE SEASON…………..20.9  DEPARTURE……-9.0

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/-14/0.01/0.3/383/69             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/-4/0.08/0.9/201/36              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/341/60                   46 WSW RMY 50
1/17 21/5/13/-12/0.00/0.0/558/98              30 WNW RMY N/A
1/18 50/19/35/+10/0.16/0.0/000/00             47 SE  RMY 52
1/19 44/28/36/+11/T/0.0/304/53                33 W   RMY 36
1/20 36/23/30/+5/0.00/0.0/495/86              28 W   RMY 28
1/21 30/17/24/-1/0.00.0.0./358/62             21 WNW RMY N/A
1/22 36/25/31/+6/T/T/…/..                   20 WNW RMY 20
1/23 36/18/27/+2/0.00/0.0/…/..              25 SSW RMY 26
1/24 32/27/30/+5/0.84/5.0/000/00              24 SSW RMY N/A
1/25 34/17/26/+1/0.00/0.0/…/..              31 W   RMY 33

1/26 morning low temp: 9F 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 26
HIGH 68F IN 1950 [RECORD FOR MONTH] LOW -5F IN 1920
PRECIP 1.60 INS. IN 1958
SNOW 9.0 INS. IN 1898
WIND 90e MPH SE IN 1978

RECORDS FOR JANUARY 27
HIGH 63F IN 1974
LOW -12F IN 1924
PRECIP 1.59 INS. IN 1996
SNOWFALL 11.7 INS. IN 2011
PEAK GUST 91 MPH SSE IN 1996

TODAY’S REPORT PREPARED BY: Brian Fitzgerald