Monday, December 31, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, DECEMBER 31, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

CLOUDS AND WARMER AIR MOVE IN AS STORMS APPROACH THE AREA
FOLLOWING LOW PRESSURE FROM THE SOUTH….

Early today skies were clear, although visibility has been moderately low all day. Hazy conditions persisted in the area, likely due to evaporation caused by warm temperatures. So far today, we have reached a high temperature of 41F, which is 6 degrees warmer than our normal high of 35F. Our low since midnight is 28F, which is 9 degrees higher than our normal daily minimum of 19F. Since mid-morning, pressure has been dropping, and the sky has become more and more obscured by clouds. As pressure drops, we are witnessing a slight increase in wind speed as well, from steady 13 mile per hour wind this morning to wind that has been frequently gusting over 20 miles per our since about 11 A.M.

Today’s Observations:

7 A.M.
Weather: Scattered cirrus, hazy
Temperature: 29F; Dew Point: 26F; Wind: SW at 7 kts
Sea-level pressure: 30.36 ins. Hg, increasing, then more quickly
Visibility: 20 miles
6-hr Max temp: 30F
6-hr Min temp: 28F
24-hr Precip: 0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1155 210 SCT 20 280/29/26/2207/036/ HAZY/ 8/001
53016 10030 20028

10 A.M.
Weather: Scattered stratus, scattered cirrus, few cumulus S-W, hazy
Temperature: 37F; Dew Point: 31F; Wind: SW at 8 kts
Sea-level pressure: 30.39 ins. Hg, increasing, then more slowly
Visibility: 20 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 40 SCT 210 SCT 20 292/37/31/2308/039/ FEW CU
S-W HAZY/ 8/801 50012

1 P.M.
Weather: Overcast cirrostratus, few cumulus in all directions, hazy
Temperature: 40F; Dew Point: 28F; Wind: SSW at 11G18 kts
Sea-level pressure: 30.32 ins. Hg, decreasing, then more slowly
Visibility: 20 miles
6-hr Max temp: 41F
6-hr Min temp: 29F
6-hr Precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1755 E250 OVC 20 267/40/28/2011G18/032/ FEW CU ALQDS
HAZY/ 8/108 56025 10041 20029 

SUMMARY FOR SUNDAY, DECEMBER 30, 2018 

TEMPERATURE (DEGREES F)
MAX…..33   NORMAL…..35
MIN…..23   NORMAL…..19
MEAN….28   NORMAL…..27

DEPARTURE FROM 30-YEAR NORMAL……………………+1
TOTAL DEPARTURE FOR THE MONTH…………………..+57 [+1.7 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..37   DEPARTURE………-1
TOTAL HEATING UNITS FOR THE MONTH………….946   DEPARTURE……..-59
TOTAL HEATING UNITS FOR THE SEASON………..2266   DEPARTURE………-1
TOTAL HEATING UNITS LAST SEASON TO DATE……2062   DIFFERENCE……+204

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..24 NNW AT 12:32 A.M.
                   AERO…………………….21 NNW AT 12:32 A.M.
                   ASOS…………………….24 NW  AT 12:00 A.M.
                   DAVIS……………………22 NNW AT 12:32 A.M. RMY 17
FASTEST MILE FOR YESTERDAY………………….16 NNW AT 12:17 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….16 NW  AT 12:44 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………17 NNW AT 12:44 A.M.
AVERAGE WIND SPEED AND DIRECTION……………5.5 NNW
                   ASOS……………………5.1
                   DAVIS…………………..5.6 WNW [303 deg.]   

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……….3.55  DEPARTURE…….-1.20
                         ASOS…………..4.22 *
TOTAL PRECIPITATION FOR THE YEAR……….66.92  DEPARTURE……+13.83
                         ASOS………….69.85 *
* ASOS MONTHLY AND ANNUAL PRECIPITATION IS SUSPECT

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……..-0.5
TOTAL SNOWFALL FOR THE MONTH…………….0.1  DEPARTURE…….-12.2
TOTAL SNOWFALL FOR THE SEASON……………7.7  DEPARTURE……..-7.2

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 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

12/01 41/28/35/-2/0.00/0.0/391/70          20 NNW AERO 18 NNW RMY N/A
12/02 52/35/44/+8/1.04/0.0/000/00          28 ESE AERO 25 ESE RMY 27
12/03 54/38/46/+10/0.00/0.0/178/32         35 W   AERO 35 W   RMY 38
12/04 38/23/31/-4/0.00/0.0/516/93          30 WNW AERO 31 WNW RMY 33
12/05 33/18/26/-9/0.00/0.0/432/78          16 NNW AERO 15 NNW RMY N/A
12/06 37/24/31/-4/0.00/0.0/354/64          29 W   AERO 28 W   RMY 30
12/07 37/21/29/-5/0.00/0.0/546/99          29 NW  AERO 29 NW  RMY 32
12/08 27/15/21/-13/0.00/0.0/518/94         28 NW  AERO 27 NW  RMY 29
12/09 34/17/26/-8/0.00/0.0/391/71          23 SSW AERO 21 SSW RMY 22
12/10 36/22/29/-4/0.00/0.0/544/99          24 NNW AERO 23 NNW RMY 22
12/11 36/17/27/-6/0.00/0.0/543/99          16 WSW AERO 14 WSW RMY N/A
12/12 35/18/27/-6/0.00/0.0/471/86          30 NW  AERO 29 NW  RMY M
12/13 31/16/24/-8/0.00/0.0/088/16          16 NNE AERO 12 SE  RMY N/A
12/14 46/28/37/+5/0.00/0.0/399/73          28 SSW AERO 28 SSW RMY 29
12/15 49/33/43/+11/0.04/0.0/000/00         28 NE  AERO 27 NE  RMY 30
12/16 40/37/39/+8/…./0.0/…/..          38 NE  AERO 38 NE  RMY 40
12/17 37/32/35/+4/…./0.0/…/..          39 NNE AERO 37 NNE RMY N/A
12/18 34/20/27/-4/0.02/0.1/…/..          48 NW  AERO 55 NW  RMY 48
12/19 38/17/28/-2/0.00/0.0/…/..          23 WNW AERO 23 WNW RMY N/A
12/20 47/30/39/+9/0.00/0.0/…/..          23 SW  AERO 22 SW  RMY N/A
12/21 62/43/53/+23/…./0.0/…/..         60 SSE AERO 62 SSE RMY 63
12/22 54/31/43/+14/…./0.0/…/..         41 W   AERO 45 W   RMY 43
12/23 38/27/33/+4/0.00/0.0/…/..          30 WNW AERO 32 WNW RMY N/A
12/24 34/27/31/+2/0.01/T/…/..            21 W   AERO 21 W   RMY N/A
12/25 35/23/29/+1/0.00/0.0/…/..          28 NW  AERO 28 NW  RMY 29
12/26 36/20/28/0/0.00/0.0/…/..           24 NW  AERO 24 NW  RMY 25
12/27 35/26/31/+3/0.00/0.0/…/..          23 NW  AERO 22 NW  RMY N/A
12/28 54/30/42/+14/…./0.0/…/.. 44 SSW AERO M  M   RMY 47
12/29 54/30/42/+15/…./…/…/..         38 WNW AERO 38 WNW RMY 38
12/30 33/23/28/+1/0.00/0.0/…/..          24 NNW AERO 21 NNW RMY 17

12/31 Low temp since midnight is 28F; normal low is 19F

DAILY RECORDS FOR DECEMBER 2018

12/21/18: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 62F,
          BREAKS PREVIOUS RECORD OF 60F SET IN 1957

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

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

RECORDS FOR JANUARY 1
HIGH 58F IN 1966
LOW -6F IN 1918
PRECIP 1.45 INS. IN 1982
SNOWFALL 7.2 INS. IN 1938
PEAK GUST 90e MPH S IN 1945

TODAY’S REPORT PREPARED BY: Samantha Richard