Thursday, January 15, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, JANUARY 15, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

LIGHT SNOW ACCUMULATES TO ALMOST HALF INCH EARLY MORNING
THEN A CHANGE TO LIGHT SNOW GRAINS AND FINALLY
A CHANGE TO LIGHT FREEZING DRIZZLE CREATES LIGHT GLAZE
TEMPS. STRUGGLING TO RISE FROM 22F BY LATE LAST EVENING
READINGS RISE SLOWLY INTO MID 20’S THIS MORNING
RIME ICE FORMING WITH FOG AND MID 20’S,
FREEZING DRIZZLE DEPOSITING THN GLAZE

After a very cold low of 11 degrees early yesterday morning
our temperatures rose only very slowly to a high for the
day of 22F by midnight.  Flurries of snow were observed
as an ocean effect snow much of yesterday before ending during
the afternoon.  Light snow began again just after midnight
early this morning and accumulated to 0.4 inch before changing
to light snow grain and freezing drizzle before the 7 A.M
morning observation.

Light freezing drizzle was becoming mixed with very light
snow grains early this afternoon as temperatures rose very
slowly through the mid 20’s.

Today’s Observations:

7 A.M.
Weather: Low overcast stratus, fog, snow grains and freezing
drizzle ended at 6:50 A.M. ,
Temperature: 22F; Dew Point: 21F; Wind: NNW at 9 kts
Sea-level pressure: 30.09 ins. Hg, decreasing slightly
Visibility: 2 miles in fog
6-hr max temp: 23F
6-hr min temp: 22F
24-hr precip.: 0.04 Trace
24-hr snowfall: 0.4 inch
Snow Depth: Trace
BHO SA 1155 E12 OVC 2F 190/22/21/3409/009/ TOTAL NEW SNW 6/24 HRS 0.4 IN
THN GLZ ZLSGE50/ 8/6// 58005 ASOS 60003 ASOS 70003
MANUAL 6004/ MANUAL 70004 10023 20022

10 A.M.
Weather: Overcast stratus (2 layers), thin glaze
Temperature: 23F; Dew Point: 22F; Wind: NNW at 8 kts,
Wind: Direction variability WNW to N
Sea-level pressure: 30.08 ins. Hg, falling slightly
Visibility: 3 miles, thin fog
3-hr precip: Trace
3-hr snowfall: None
BHO SA 1455 E9 BKN 16 OVC 3F 185/23/22/3308/008/ THN GLZ ZLEUKN VRY LGT
WND 30V36/ 8/6// 58005 MANUAL 6000/

1 P.M.
Weather: Obscurement with fog, light freezing drizzle,
light snow grains, light rime icing, heavy fog
Temperature: 25F; Dew Point: 25F; Wind: NW at 6 kts,
Sea-level pressure: 29.99 ins. Hg, falling then more rapidly
Visibility: 1/8 mile, light freezing drizzle, light snow grains,
and heavy fog with rime icing
6-hr max temp: 25F
6-hr min temp: 22F
6-hr precip: 0.01 in.
6-hr snowfall: Trace
BHO SA 1755 W4 X 1/8ZL-SG-F 155/25/25/3206/999/SGBUKN VRY LGT
LGT RIME ICING THN GLZ/ 8//// 58030 MANUAL 6001/ ASOS 60001
10025 20022

SUMMARY FOR WEDNESDAY, JANUARY 14, 2015

TEMPERATURE (DEGREES F)
MAX…..22   NORMAL…..34
MIN…..11   NORMAL…..17
MEAN….17   NORMAL…..25

DEPARTURE FROM 30-YEAR NORMAL……………………..-8
TOTAL DEPARTURE FOR THE MONTH…………………….-41 [-3.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..48  DEPARTURE………..+8
TOTAL HEATING UNITS FOR THE MONTH………….590  DEPARTURE……….+42
TOTAL HEATING UNITS FOR THE SEASON………..2650  DEPARTURE………-202
TOTAL HEATING UNITS LAST SEASON TO DATE……2820  DIFFERENCE……..-170

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………18  NNW  AT  9:09 P.M.
ASOS…………………..20  N    AT 11:39 P.M.
DAVIS………………….16  N    AT  8:52 A.M. RMY 16
FASTEST MILE FOR YESTERDAY………………..15  N    AT  9:08 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..15  N    AT  9:11 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….12  N    AT  8:56 A.M.
AVERAGE WIND SPEED AND DIRECTION…………..9.3 NNW
ASOS………………….10.2
DAVIS…………………9.8  NNW [340 degrees] * last of several occurrences….

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.04  DEPARTURE…..-0.10
ASOS…………..0.03
TOTAL PRECIPITATION FOR THE MONTH……….1.49  DEPARTURE…..-0.46
ASOS…………..1.53
TOTAL PRECIPITATION FOR THE YEAR………..1.49  DEPARTURE…..-0.46
ASOS…………..1.53

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.4  DEPARTURE……-0.2
TOTAL SNOWFALL FOR THE MONTH…………….4.5  DEPARTURE……-3.4
TOTAL SNOWFALL FOR THE SEASON…………..15.5  DEPARTURE……-8.4

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/…/..              29 SSW RMY 30
1/2  37/26/32/+5/0.00/0.0/…/..              35 WSW RMY 38
1/3  34/21/28/+2/0.67/2.5/…/..              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/…/..              48 W   RMY 54
1/6  15/10/13/-13/0.02/0.4/…/..             29 W   RMY N/A
1/7  22/01/12/-14/0.01/0.3/…/..             43 WNW RMY 47
1/8  16/-5/6/-20/0.00/0.0/…/..              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/…/..              26 WNW RMY 27
1/11 31/9/20/-5/45/0.00/0.0/…/..            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/…/..              30 NNW RMY 29
1/14 22/11/17/-8/T/T/000/00                   18 NNW RMY 16

1/15 morning low temp: 22F 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 15
HIGH 64F IN 1995
LOW -16F IN 1957 [RECORD FOR MONTH] PRECIP 2.63 INS. IN 1958
SNOWFALL 8.8 INS. IN 1983
PEAK GUST 69e MPH SE IN 1940

RECORDS FOR JANUARY 16
HIGH 63F IN 1995
LOW -12F IN 2004
PRECIP 1.32 INS. IN 1936
SNOWFALL 14.0 INS. IN 1965
PEAK GUST 79 MPH WNW IN 1960

TODAY’S REPORT PREPARED BY: Robert Skilling