Wednesday, April 4, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, APRIL 4, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

A FOGGY, DRIZZLY DAY WITH INCREASING WINDS ON
GREAT BLUE HILL….

Fog and a light drizzle was observed today, limiting
visibility to less than two miles for most of the day.
Winds increased since this morning, reaching 22 mph by
1:00 P.M. A peak gust of 38 mph was observed at
12:41 P.M. We observed a maximum temperature of 55F at
1:00 P.M., 4 degrees above the normal of 51F. The low
since midnight was 36F,3 degrees above the normal minimum
of 33F. Winds continued to increase, with rain beginning
around 3:00 P.M.

PRELIMINARY STATS FOR MARCH 2018

TEMPERATURE, Deg. F
Avg. Max. 41.2 [-3.1] Avg. Min. 27.9 [+1.3] Mean      34.6 [-0.9] 24-hour corrected mean: 33.9
Max. for month: 62F on 30th
Min. for month: 10F on 18th

HEATING DEGREE DAYS
Total heating units:   941  [+25] Total for the season: 4063 [-421] Total for last season: 4902

PRECIPITATION, Inches
Total: 8.68 [+3.29] Greatest in 24 hrs: 3.47 on the 2nd

SNOWFALL, Inches
Total: 45.5 [+32.8] Greatest in 24 hrs: 23.0 in. on 13th

WIND, mph
Avg. uncorrected wind speed: 13.9
Avg. corrected wind speed: 14.3
Prevailing wind direction: NW at 14%
Peak gust and direction: 73 NNE on 2nd

SUNSHINE:
Campbell-Stokes card minutes: 8742 minutes of possible 21516 or 41%
Astronomical total minutes: 9023 minutes of possible 22243 or 41%

Blue Hill Observatory Greatest March Snowfall Totals,
Inches (1885-2018)

1) 52.0 in 1956
2) 45.5 in 2018
3) 42.2 in 1916
4) 41.4 in 2001
5) 41.0 in 1967
6) 37.8 in 2013
7) 35.5 in 1993

BHO Greatest March Monthly Precipitation,
inches (1885-2018):

1) 18.81 in 2010
2) 13.07 in 2001
3) 10.96 in 1968
4) 10.02 in 1983
5) 9.53 in 1953
6) 9.00 in 1984
7) 8.72 in 1993
8) 8.69 in 2018
9) 8.09 in 1956
10) 7.98 in 1994

Today’s Observations:

7 A.M.
Weather: Overcast nimbostratus, light drizzle
Temperature: 34F; Dew Point: 29F; Wind: S at 8G12 kts
Sea-level pressure: 29.65 ins. Hg, falling steadily
Visibility: 1/8 mile, fog
6-hr Max temp: 39F
6-hr Min temp: 36F
24-hr precip:  0.54
24-hr snowfall: 0.0
Snow depth: 0 in.
BHO SA 1155 W3 X 1/8L-F 039/39/39/1708G12/965/ PCPN VRY LGT/ 8////
57035 MANUAL 70054 ASOS 70042 10039 20036

10 A.M.
Weather: Overcast nimbostratus, light drizzle
Temperature: 46F; Dew Point: 46F; Wind: S at 13G19 kts
Sea-level pressure: 29.52 ins. Hg, falling, then more rapidly
Visibility: 1/16 miles, fog
3-hr precip: Trace
3-hr snowfall: 0.0 ins.
BHO SA 1455 W2 X 1/16L-F 997/46/46/1913G19/952/ PCPN VRY LGT/ 8////
58042

1 P.M.
Weather: Overcast nimbostratus, light drizzle
Temperature: 55F; Dew Point: 55F; Wind: S at 18G31 kts,
Peak Wind: 33 kts (38 mph) S at 12:41 P.M.
Sea-level pressure: 29.39 ins. Hg, falling, then more slowly
Visibility: 2 miles, fog
6-hr Max temp: 48F
6-hr Min temp: 34F
6-hr precip: Trace
6-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1755 W2 X 2L-F 951/55/55/1918G31/939/ PCPN VRY LGT PK WND
1933/41/ 8//// 56046 10055 20039

SUMMARY FOR TUESDAY, APRIL 3, 2018

TEMPERATURE (DEGREES F)
MAX…..48   NORMAL…..51
MIN…..30   NORMAL…..33
MEAN….39   NORMAL…..42

DEPARTURE FROM 30-YEAR NORMAL………………………-3
TOTAL DEPARTURE FOR THE MONTH………………………-5 [-1.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….26   DEPARTURE……….+3
TOTAL HEATING UNITS FOR THE MONTH………….76   DEPARTURE……….+2
TOTAL HEATING UNITS FOR THE SEASON……….5139   DEPARTURE……..-416
TOTAL HEATING UNITS LAST SEASON TO DATE…..4974   DIFFERENCE…….+165

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….28 SSE AT 10:18 A.M.
AERO……………………25 SSE AT 10:18 A.M.
ASOS……………………26 SSE AT 10:18 A.M.
DAVIS…………………..24 M   AT 10:17 A.M ** RMY 25
FASTEST MILE FOR YESTERDAY…………………18 SSE AT 10:15 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………26 SSE AT 10:18 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..24 M   AT 10:17 A.M.**
AVERAGE WIND SPEED AND DIRECTION………….10.2 SSW
ASOS………………….10.4
DAVIS………………….9.4

** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.54  DEPARTURE……-0.04
ASOS…………..0.42
TOTAL PRECIPITATION FOR THE MONTH……….0.67  DEPARTURE……+0.16
ASOS…………..0.55
TOTAL PRECIPITATION FOR THE YEAR……….19.47  DEPARTURE……+5.17
ASOS………….20.79

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……..-0.2
TOTAL SNOWFALL FOR THE MONTH…………….1.6  DEPARTURE……..+1.0
TOTAL SNOWFALL FOR THE SEASON…………..91.8  DEPARTURE…….+31.4

PRELIMINARY CLIMATE SUMMARY FOR MARCH 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

3/01 61/37/49/+18/0.00/0.0/378/56    39 ENE AERO 37 ENE RMY N/A
3/02 40/32/36/+5/3.47/0.7/000/00     73 NNE AERO 70 NNE RMY N/A
3/03 40/32/26/+4/T/T/034/05          52 NNE AERO 50 NNE RMY 49
3/04 39/34/37/+5/T/T/000/00          36 NNE AERO 32 NNE RMY 32
3/05 40/29/35/+3/0.12/1.2/261/38     40 NE  AERO 39 NE  RMY 40
3/06 34/29/32/0/0.00/0.0/062/09      20 N   AERO 16 N   RMY N/A
3/07 35/31/33/0/1.49/10.0/000/00     52 ENE AERO 53 ENE RMY 50
3/08 34/28/31/-2/0.67/5.0/000/00     44 NNE AERO 47 NNE RMY N/A
3/09 36/24/30/-3/T/T/265/38          28 W   AERO 26 W   RMY N/A
3/10 37/28/33/0/0.00/0.0/343/49      38 WNW AERO 38 WNW RMY 41
3/11 42/26/34/0/0.00/0.0/583/83      28 NW  AERO 26 NW  RMY 29
3/12 39/26/33/-1/T/T/155/22          36 ENE AERO 33 ENE RMY N/A
3/13 35/26/31/-3/2.20/23.0/000/00    60 N   AERO 60 N   RMY 64
3/14 36/24/30/-5/0.00/0.0/470/66     38 WSW AERO 38 WSW RMY 41
3/15 40/29/35/0/0.01/0.2/422/59      44 W   AERO 44 W   RMY 44
3/16 35/23/29/-6/0.00/0.0/308/43     41 NW  AERO 41 NW  RMY 45
3/17 40/15/28/-8/0.00/0.0/533/74     46 W   AERO 45 W   RMY 49
3/18 31/10/21/-15/0.00/0.0/694/96    39 NW  AERO 38 NW  RMY 40
3/19 35/13/24/-12/0.00/0.0/704/97    32 WNW AERO 32 WNW RMY 34
3/20 40/18/29/-8/0.00/0.0/372/51     23 NW  AERO 21 NW  RMY N/A
3/21 35/31/33/-4/0.04/0.2/000/00     43 NE  AERO 44 NE  RMY N/A
3/22 39/30/35/-2/0.41/3.4/000/00     28 NNW AERO 26 NNW RMY 30
3/23 44/28/36/-2/0.00/0.0/539/73     21 NNW AERO 18 NNW RMY 21
3/24 45/32/39/+1/T/T/185/25          23 NE  AERO 21 NE  RMY N/A
3/25 36/29/33/-5/0.18/1.8/134/18     35 NNE AERO 30 NNE RMY 33
3/26 38/27/33/-6/0.00/0.0/701/94     33 NE  AERO 26 NE  RMY 30
3/27 44/25/35/-4/0.00/0.0/592/79     24 NE  AERO 17 NE  RMY 20
3/28 55/33/44/+5/0.01/0.0/293/39     21 SSW AERO 14 SSW RMY 18
3/29 55/39/47/+7/T/0.0/242/32        24 SSE AERO 21 SSE RMY N/A
3/30 62/42/52/+12/0.08/0.0/000/00    32 NW  AERO 30 NW  RMY N/A
3/31 56/35/46/+5/T/0.0/731/96        37 NW  AERO 36 NW  RMY N/A

DAILY RECORDS FOR MARCH 2018

3/02/18: NEW DAILY RECORD MAXIMUM PRECIPITATION OF 3.47 INS.
PREVIOUS RECORD WAS 2.15 INS. SET IN 1983

3/13/18: NEW DAILY RECORD MAXIMUM SNOWFALL OF 23.0 INS.
PREVIOUS RECORD WAS 10.0 INS. SET IN 1993

3/13/18: NEW MONTHLY RECORD MAXIMUM DAILY SNOWFALL OF 23.0 INS.
PREVIOUS RECORD WAS 18.0 INS. SET ON 8 MARCH 2013

PRELIMINARY CLIMATE SUMMARY FOR APRIL 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

4/01 58/33/46/+5/…./0.0/…/..   45 SSW AERO 43 SSW RMY N/A
4/02 38/30/34/-7/…./1.6/…/..   20 SSW AERO 15 SSW RMY 17
4/03 48/30/39/-3/…./0.0/…/..   28 SSE AERO 25 SSE RMY 25

4/4 Low temp since midnight is 36F; normal low is now 33F

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

RECORDS FOR APRIL 4
HIGH 76 IN 2010
LOW 12 IN 1954
PRECIP 1.45 IN. IN 1987
SNOWFALL 7.3 IN. IN 2016
PEAK GUST 80 MPH WNW IN 1963

RECORDS FOR APRIL 5
HIGH 81 IN 1928
LOW 15 IN 1995
PRECIP 2.15 IN. IN 1987
SNOWFALL 4.0 IN. IN 1898
PEAK GUST 76 MPH WNW IN 1963

TODAY’S REPORT PREPARED BY: Benjamin Turner and K.A. Geagan