Sunday, April 8, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, APRIL 8, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

CLOUDY SKIES WITH BELOW AVERAGE TEMPERATURES

Low level clouds have been increasing since this
morning, leaving skies with few breaks for sunshine.
It was quite breezy at the summit as the winds shifted
from the WNW to the N.
The maximum temperature observed so far today, 38F, is well
below the normal high of 53F. The low since midnight was 29F,
also below normal.
Visibility has been 70 miles on average most of the day
with the exception being from the SE-S, where lower visibility
has prevailed.

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 [+3.10] 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) 8.68 in 2018
9) 8.09 in 1956
10) 7.98 in 1994

Today’s Observations:

7 A.M.
Weather: Broken Cirrostratus, Scattered Altostratus,
Few Cumulus NE-ESE
Temperature: 31F; Dew Point: 16F; Wind: N at 7 kts
Sea-level pressure: 29.84 ins. Hg, falling then rising
Visibility: 80 miles, 40 miles E-SSE
6-hr Max temp: 36F
6-hr Min temp: 29F
24-hr precip:  0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1155 180 SCT E220 BKN 80 104/31/16/3507/983/
FEW CU NE-ESE VSBY 40 E-SSE/ 8/128 55000 10036 20029

10 A.M.
Weather: Broken Altostratus, Scattered Cumulus
Temperature: 37F; Dew Point: 18F; Wind: N at 9G18 kts,
Sea-level pressure: 29.82 ins. Hg, falling then rising but lower
Visibility: 70 miles, 50 miles SSE-S
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins.
BHO SA 1455 55 SCT E220 BKN 70 099/37/18/0309G18/982/
VSBY 50 SSE-S/ 8/12/ 55005

1 P.M.
Weather: Scattered Stratocumulus, Scattered Cirrostratus
Temperature: 38F; Dew Point: 18F; Wind: N at 07 kts
Sea-level pressure: 29.81 ins. Hg, falling then more slowly
Visibility: 70 miles
6-hr Max temp: 38F
6-hr Min temp: 31F
6-hr precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1755 50 SCT 250 SCT 70 081/38/18/0107/977/
8/4// 56018 10038 20031

SUMMARY FOR SATURDAY, APRIL 7, 2018

TEMPERATURE (DEGREES F)
MAX…..46   NORMAL…..52
MIN…..32   NORMAL…..35
MEAN….39   NORMAL…..43

DEPARTURE FROM 30-YEAR NORMAL………………………-4
TOTAL DEPARTURE FOR THE MONTH……………………..-25 [-2.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….26   DEPARTURE……….+4
TOTAL HEATING UNITS FOR THE MONTH…………185   DEPARTURE………+25
TOTAL HEATING UNITS FOR THE SEASON……….5243   DEPARTURE……..-401
TOTAL HEATING UNITS LAST SEASON TO DATE…..5066   DIFFERENCE…….+177

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….32 WNW AT 9:00 A.M.
AERO……………………35 WNW AT 9:00 A.M.
ASOS……………………33 NW  AT 9:01 A.M.
DAVIS…………………..32 M   AT 8:45 A.M ** RMY 34
FASTEST MILE FOR YESTERDAY…………………23 WNW AT 9:01 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………24 WNW AT 9:01 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..22 M   AT 9:01 A.M.**
AVERAGE WIND SPEED AND DIRECTION………….11.4 NW
ASOS………………….11.3
DAVIS…………………10.0 M

** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.17
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.13  DEPARTURE……-0.06
ASOS…………..0.82
TOTAL PRECIPITATION FOR THE YEAR……….19.93  DEPARTURE……+4.92
ASOS………….21.06

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……..-0.1
TOTAL SNOWFALL FOR THE MONTH…………….2.6  DEPARTURE……..+1.4
TOTAL SNOWFALL FOR THE SEASON…………..92.8  DEPARTURE…….+31.8

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
4/04 54/36/45/+3/…./0.0/…/..   56 WNW AERO 56 WNW RMY 54
4/05 40/27/34/-9/0.00/0.0/…/..   53 WNW AERO 53 WNW RMY 52
4/06 41/25/33/-10/0.25/1.0/…/..  37 S   AERO 36 S   RMY 38
4/07 46/32/35/-4/0.00/0.0/…/..   32 WNW AERO 35 WNW RMY 34

4/08 Low temp since midnight is 29F; normal low is now 35F

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

RECORDS FOR APRIL 8
HIGH 87 IN 1991
LOW 17 IN 1888
PRECIP 1.78 IN. IN 1956
SNOWFALL 9.3 IN. IN 1956
PEAK GUST 70 MPH S IN 2000

RECORDS FOR APRIL 9
HIGH 83 IN 1991
LOW 18 IN 1888
PRECIP 2.38 IN. IN 1935
SNOWFALL 11.0 IN. IN 1917
PEAK GUST 72 MPH WNW IN 1962

TODAY’S REPORT PREPARED BY: Robert Millette