Thursday, January 18, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, JANUARY 18, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

COOL AND CLOUDY MORNING WITH A MILD AND SUNNY
AFTERNOON….

A snow storm began yesterday morning just after
5:00 A.M. leaving 2.3 ins. on top of Great Blue
Hill. Today began with broken altocumulus clouds
but cleared by mid-morning making for a sunny
with only a few altocumulus clouds. Temperatures
have been slightly below seasonable with a high
of 29F so far. The normal for today is 33F.
Yesterday temperatures stayed fairly constant
with a high of 32F and a low of 29F. This was
due to the high moisture content in the air.
The humidity has decreased throughout the day
today and we could see 70 miles of visibility
by 1:00 P.M.

Today’s Observations:

7 A.M.
Weather: Broken altocumulus, smoke layer along horizon
Temperature: 17F; Dew Point: 17F; Wind: WNW at 8 kts
Sea-level pressure: 29.96 ins. Hg, falling, then steady
Visibility: 40 miles
6-hr Max temp: 29F
6-hr Min temp: 16F
24-hr precip: 0.16 ins.
24-hr snowfall: 1.8 ins.
Snow depth: 2 ins.
BHO SA 1155 E200 BKN 40 144/17/17/2908/996/ NEW SNW PST
24 HRS 1.8 INS STORM TOTAL 2.3 INS K LYR ALG HRZN/
8/060 4/002 56003 MANUAL 70016 ASOS 70019 10029 20016

10 A.M.
Weather: Clear, few altocumulus ENE-SSW,
smoke layer along horizon
Temperature: 22F; Dew Point: 18F; Wind: ENE at WNW 5 kts,
Wind: Light
Sea-level pressure: 29.96 ins. Hg, falling then steady
Visibility: 45 miles
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins.
BHO SA 1455 CLR 45 145/22/18/3005/996/ FEW AC ENE-SSW K LYR
ALG HRZN WND LGT/ 8/060 53001

1 P.M.
Weather: Clear, few altocumulus ENE-S
smoke layer along horizon
Temperature: 28F; Dew Point: 20F; Wind: NW at 11G17 kts
Sea-level pressure: 29.86 ins. Hg, falling, then more slowly
Visibility: 70 miles
6-hr precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
6-hr Max temp: 29F
6-hr Min temp: 16F
BHO SA 1755 CLR 70 112/28/20/3111G17/986/ FEW AC ENE-S K LYR
ALG HRZN/ 8/060 4/002 58033 10029 20016

SUMMARY FOR WEDNESDAY, JANUARY 17, 2018

TEMPERATURE (DEGREES F)
MAX…..32   NORMAL…..33
MIN…..29   NORMAL…..17
MEAN….31   NORMAL…..25

DEPARTURE FROM 30-YEAR NORMAL………………………+6
TOTAL DEPARTURE FOR THE MONTH……………………..-61 [-3.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….34  DEPARTURE……….-6
TOTAL HEATING UNITS FOR THE MONTH…………730  DEPARTURE………+62
TOTAL HEATING UNITS FOR THE SEASON……….2852  DEPARTURE……..-120
TOTAL HEATING UNITS LAST SEASON TO DATE…..2615  DIFFERENCE…….+237

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….20 SE  AT 3:33 A.M.
AERO……………………17 SE  AT 3:35 A.M.
ASOS……………………18 SSE AT 3:34 A.M.
DAVIS…………………..17 M   AT 2:58 A.M.* RMY N/A
FASTEST MILE FOR YESTERDAY…………………14 SE  AT 3:05 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………14 SE  AT 3:07 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..14 M   AT 3:07 A.M.*
AVERAGE WIND SPEED AND DIRECTION…………..7.5 NW
ASOS…………………..8.2
DAVIS………………….7.0*

*DAVIS DIRECTON MALFUNCTIONING

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.16  DEPARTURE……+0.01
ASOS…………..0.19
TOTAL PRECIPITATION FOR THE MONTH……….4.19  DEPARTURE……+1.76
ASOS…………..4.63
TOTAL PRECIPITATION FOR THE YEAR………..4.19  DEPARTURE……+1.76
ASOS…………..4.63

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….1.8  DEPARTURE………1.2
TOTAL SNOWFALL FOR THE MONTH……………19.3  DEPARTURE……..+9.7
TOTAL SNOWFALL FOR THE SEASON…………..28.6  DEPARTURE……..+3.0

PRELIMINARY CLIMATE SUMMARY FOR JANUARY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST
AERO: Aerovane wind recording system 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
M:    Missing data

1/01 11/-5/3/-24/0.00/0.0/…/..        30 NW  AERO 30 NW  RMY 31
1/02 15/-2/7/-20/0.00/0.0/…/..        26 W   AERO 25 W   RMY 26
1/03 28/11/20/-6/0.00/0.0/…/..        23 WSW AERO 20 WSW RMY N/A
1/04 28/18/23/-3/1.66/16.5/000/00       54 NNW AERO 60 NNW RMY 64
1/05 18/2/10/-16/0.00/0.0/…/..        53 W   AERO 53 W   RMY 57
1/06 10/-2/4/-22/0.00/0.0/…/..        43 WSW AERO 47 WSW RMY 47
1/07 14/-8/3/-23/0.00/0.0/…/..        37 WNW AERO 35 WNW RMY N/A
1/08 33/14/24/-2/T/T/…/..             40 S   AERO 40 S   RMY 42
1/09 40/25/33/+7/T/T/…/..             37 W   AERO 35 W   RMY 33
1/10 36/20/28/+3/0.00/0.0/…/..        30 W   AERO 30 W   RMY N/A
1/11 50/32/41/+16/0.00/0.0/…/..       33 S   AERO 32 S   RMY 34
1/12 60/45/53/+28/…./0.0/…/..       56 S   AERO 56 S   RMY 55
1/13 60/17/39/+14/T/0.0/…/..          58 SSW AERO 60 SSW RMY 62
1/14 21/11/16/-9/0.00/0.0/…/..        30 NW  AERO 30 NW  RMY N/A
1/15 18/11/15/-10/…./…/…/..       23 NNW AERO 21 N   RMY 23
1/16 31/18/25/0/0.00/0.0/…/..         17 SSE AERO 15 SSE RMY N/A
1/17 32/29/31/+6/0.23/2.3/…/..        20 SE  AERO 17 SE  RMY N/A

1/17 Low temp since midnight is 16F; normal low is now 17F

DAILY RECORDS FOR JANUARY 2018

01/04/18: NEW DAILY RECORD MAXIMUM SNOWFALL OF 16.5 INS.
PREVIOUS RECORD WAS 8.6 INS. SET IN 1923 AND
TIED IN 1942

01/07/18: DAILY RECORD LOW MINIMUM TEMPERATURE OF -8F,
PREVIOUS RECORD OF -7F WAS SET IN 1896

01/12/18: DAILY RECORD HIGH MINUMUM TEMPERATURE OF 45F,
PREVIOUS RECORD OF 42F WAS SET IN 2017

DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 60F,
PREVIOUS RECORD OF 59F WAS SET IN 2017

01/13/18: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 60F,
PREVIOUS RECORD OF 57F WAS SET IN 1890 AND
TIED IN 1932

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: Kaitlin Ann Geagan