Tuesday, December 30, 2014

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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, DECEMBER 30, 2014
ALL TIMES ARE IN EASTERN STANDARD TIME

MERCURY DROPS OVERNIGHT TO 19F, PLENTIFUL
SUNSHINE ONCE AGAIN

Winds shifted from W to NNW overnight allowing
additional cold and dry air to enter the region with
a morning low of 19F, the coldest reading since the 8th of
the month. This marked only the 3rd day for the month
of December that the mercury had reached the teens. The
coldest reading of the season still remains at 16F which
also occurred on December 8th. With cold temperatures and
dew points remaining in the upper single digits to lower
teens today, snow guns have been going full blast at
the ski area today.

By the 1:00 PM EST observation two layers of cirrus were
scattered covering 4/8 of the sky with plenty of cool,
dry air in place. Visibility ranged from 70 to 80 plus
miles in the NW with a maximum of 27F recorded so far.

Today’s Observations:

7 A.M.
Weather: Broken cirrus, few stratocumulus distant
offshore NE-SE
Temperature: 20F; Dew Point: 9F; Wind: NNW at 7 kts
Sea-level pressure: 30.32 ins. Hg, increasing, then more quickly
Visibility: 70 miles
6-hr max temp: 25F
6-hr min temp: 19F
24-hr precip.: 0.00 ins
BHO SA 1155 E200 BKN 70 267/20/9/3307/032/ FEW SC DSNT OFFSHR
NE-SE/ 8/504 53010 10025 20019

10 A.M.
Weather: Broken cirrus, few stratocumulus distant
offshore NE-SE, few cumulus distant NW
Temperature: 25F; Dew Point: 12F; Wind: NW at 8 kts
Sea-level pressure: 30.14 ins. Hg, rising, then more quickly
Visibility: 70 miles, except 80 miles WNW-NNE
BHO SA 1455 E200 BKN 70 277/25/12/3208/035/ VSBY WNW-NNE 80 MI
FEW SC DSNT OFFSHR NE-SE FEW CU DSNT NW/ 8/504 53010

1 P.M.
Weather: Scattered cirrus, scattered cirrus lower,
few stratocumulus distant offshore ENE-SE
Temperature: 27F; Dew Point: 10F; Wind: estimated W at 6 kts,
Wind Speed: Light
Sea-level pressure: 30.28 ins. Hg, rising, then falling and lower
Visibility: 70 miles, except 80 miles WSW-NNE
6-hr max temp: 27F
6-hr min temp: 20F
BHO SA 1755 200 SCT 250 SCT 80 255/27/10/E2806/028/ VSBY WSW-NNE
80 MI FEW SC DSNT OFFSHR ENE-SE WND LGT/ 8/501 58022 10027 20020

SUMMARY FOR MONDAY, DECEMBER 29, 2014

TEMPERATURE (DEGREES F)
MAX…..41   NORMAL…..35
MIN…..26   NORMAL…..20
MEAN….34   NORMAL…..27

DEPARTURE FROM 30-YEAR NORMAL……………………..+7
TOTAL DEPARTURE FOR THE MONTH……………………+129 [+4.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..31  DEPARTURE………..-7
TOTAL HEATING UNITS FOR THE MONTH………….821  DEPARTURE………-146
TOTAL HEATING UNITS FOR THE SEASON………..1980  DEPARTURE………-249
TOTAL HEATING UNITS LAST SEASON TO DATE……2193  DIFFERENCE……..-213

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………23  WNW  AT  12:48 P.M.
ASOS…………………..24  W    AT  12:57 P.M.
DAVIS………………….22  WNW  AT  12:48 P.M. RMY 23
FASTEST MILE FOR YESTERDAY………………..17  WNW  AT  12:33 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..18  W    AT   3:55 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….16  W    AT  11:59 P.M.
AVERAGE WIND SPEED AND DIRECTION………….10.3 WNW
ASOS………………….10.7
DAVIS…………………8.7 WNW [287 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……….7.21  DEPARTURE…..+2.60
ASOS…………..7.44
TOTAL PRECIPITATION FOR THE YEAR……….54.97  DEPARTURE…..+1.83
ASOS………….55.63

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……-0.5
TOTAL SNOWFALL FOR THE MONTH…………….2.3  DEPARTURE…..-10.0
TOTAL SNOWFALL FOR THE SEASON…………..11.0  DEPARTURE……-3.9

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 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

12/1  63/37/50/+13/0.01/0.0/391/70             28 WNW RMY 31
12/2  37/30/34/-2/0.10/T/000/00                26 E   RMY 29
12/3  49/34/42/+6/0.31/0.0/000/00              40 W   RMY 43
12/4  41/27/34/-1/0.00/0.0/505/91              29 WNW RMY N/A
12/5  42/23/33/-2/0.12/0.0/382/69              21 E   RMY 22
12/6  43/36/40/+5/0.99/0.0/000/00              25 NNW RMY N/A
12/7  36/18/27/-7/0.15/0.0/193/35              31 N   RMY 34
12/8  25/16/21/-13/0.01/0.1/000/00             24 N   RMY N/A
12/9  48/25/37/+3/3.23/0.0/000/00              48 ENE RMY 52
12/10 47/35/41/+8/0.43/0.0/000/00              35 NNE RMY 37
12/11 35/29/32/-1/0.05/0.5/000/00              27 SW  RMY 27
12/12 36/26/31/-2/0.00/0.0/230/42              23 WNW RMY 25
12/13 40/27/34/+2/0.00/0.0/191/35              28 NW  RMY 28
12/14 43/28/36/+4/0.00/0.0/377/69              20 NW  RMY 20
12/15 41/28/35/+3/0.00/0.0/536/98              17 NW  RMY 17
12/16 42/33/38/+7/T/T/011/02                   17 E   RMY N/A
12/17 45/37/41/+10/0.43/0.0/000/00             27 W   RMY N/A
12/18 41/32/37/+6/0.02/T/213/39                35 WNW RMY 38
12/19 34/25/30/0/0.00/0.0/000/00               26 NW  RMY 29
12/20 32/24/28/-2/…./…/164/30              21 NNE RMY 23
12/21 31/29/30/+0/…./…/000/00              20 NNE RMY 22
12/22 42/29/36/+7/…./0.0/…/..              23 E   RMY N/A
12/23 44/39/42/+13/…./0.0/000/00             28 ENE RMY 30
12/24 61/40/51/+22/…./0.0/000/00             32 SSW RMY 41
12/25 61/41/51/+23/…./0.0/…/..             37 W   RMY 43
12/26 47/35/41/+13/0.00/0.0/…/..             24 WSW RMY 28
12/27 50/35/43/+15/0.00/0.0/…/..             21 SSW RMY N/A
12/28 49/35/42/+14/0.02/0.0/…/..             31 W   RMY 36
12/29 41/26/34/+7/0.00/0.0/…/..              23 WNW RMY 23

12/30 morning low temp: 19F since midnight; normal low is now 19F

DAILY RECORDS FOR DECEMBER 2014:

-DAILY PRECIPITATION RECORD FOR DECEMBER 9 2014
Old record of 1.51 inches set in 1952,
replaced with new record of 3.23 inches.

-DAILY TEMPERATURE RECORD FOR DECEMBER 24 2014
Old record of 58F set in 1996,
replaced with new record of 61F.

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

RECORDS FOR DECEMBER 30
HIGH 60 IN 1984
LOW -18 IN 1933
PRECIP 1.48 INS. IN 1891
SNOWFALL 7.5 INS. IN 1956
PEAK GUST 81 MPH WNW IN 1962

RECORDS FOR DECEMBER 31
HIGH 62 IN 1965
LOW -12 IN 1917
PRECIP 0.96 INS. IN 1906
SNOWFALL 7.5 INS. IN 2008
PEAK GUST 78 MPH NW IN 1990

TODAY’S REPORT PREPARED BY: Brian Fitzgerald