Saturday, April 7, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, APRIL 7, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

A CLEARER, DRIER DAY FOLLOWING YESTERDAY’S SNOW
AND RAIN…

We measured an inch of snow and 0.25 inches of
liquid precipitation from yesterday. Today, a
decrease in the overcast this morning left almost
clear skies by 1:00 P.M. It was quite breezy on
Great Blue Hill, with multiple gusts around 20 mph
and a peak gust at 32 mph at 9:00 A.M. The maximum
temperature observed so far today was 44F, 8 degrees
below the normal maximum of 52F. The low since
midnight was a near seasonable 34F, one degree below
the normal of 35F. Visibility has been 70 miles on
average most of the day, due to drier air entering
the region.

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: Overcast altostratus, few stratus fractus W-NW,
few lower stratocumulus in all directions, higher clouds
visible W-N
Temperature: 30F; Dew Point: 14F; Wind: WNW at 13G22 kts
Sea-level pressure: 30.84 ins. Hg, rising steadily
Visibility: 75 miles, 75 miles WNW-NW, 55 miles NE
6-hr Max temp: 30F
6-hr Min temp: 25F
24-hr precip:  0.27 ins.
24-hr snowfall: 1.0 ins.
Snow depth: 0 ins.
BHO SA 1155 E75 OVC 65 084/34/29/2913G22/978/ FEW STFRA DSNT
W-NW FEW LWR SC ALQDS HIR CLDS VSBL DSNT W-N VSBY WNW-NW 75
NE 55 TOTAL NEW SNW PST 24 HRS 1.0 IN/ 8/57/ 52016 MANUAL
70025 ASOS 70027 10037 20034

10 A.M.
Weather: Scattered altostratus, broken cirrostratus
Temperature: 35F; Dew Point: 26F; Wind: WNW at 14G26 kts,
Peak Wind: 28 WNW at 9:00 AM
Sea-level pressure: 29.80 ins. Hg, rising then falling
Visibility: 70 miles, 80 miles WNW-NW, 60 miles NE-SE
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins.
BHO SA 1455 100 SCT E220 BKN 70 093/35/26/2914G26/980/ FEW CU
SE-NE BINOVC W-NNE VSBY WNW-NW 80 NE-SE 60 PK WND 2928/00/
8/177 50009

1 P.M.
Weather: Scattered cirrostratus, few cumulus in all directions,
few altocumulus E-SSW
Temperature: 43F; Dew Point: 16F; Wind: WNW at 10G21 kts
Sea-level pressure: 29.81 ins. Hg, rising then falling
Visibility: 75 miles
6-hr Max temp: 44F
6-hr Min temp: 33F
6-hr precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1755 250 SCT 75 095/43/16/3010G21/981/ FEW CU ALQDS FEW
AC E-SSW/ 8/177 50002 10044 20033

SUMMARY FOR FRIDAY, APRIL 6, 2018

TEMPERATURE (DEGREES F)
MAX…..41   NORMAL…..52
MIN…..25   NORMAL…..34
MEAN….33   NORMAL…..43

DEPARTURE FROM 30-YEAR NORMAL……………………..-10
TOTAL DEPARTURE FOR THE MONTH……………………..-21 [-2.0 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….32   DEPARTURE………+10
TOTAL HEATING UNITS FOR THE MONTH…………159   DEPARTURE………+21
TOTAL HEATING UNITS FOR THE SEASON……….5217   DEPARTURE……..-405
TOTAL HEATING UNITS LAST SEASON TO DATE…..5047   DIFFERENCE…….+170

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….37 S   AT  10:27 A.M.
AERO……………………36 S   AT  10:27 A.M.
ASOS……………………36 S   AT  10:27 A.M.
DAVIS…………………..34 M   AT  10:26 A.M ** RMY 38
FASTEST MILE FOR YESTERDAY…………………25 S   AT  10:26 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………25 S   AT  10:26 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..23 M   AT  10:25 A.M.**
AVERAGE WIND SPEED AND DIRECTION………….12.2 SSW
ASOS………………….12.3
DAVIS…………………11.3 M

** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.25  DEPARTURE……+0.08
ASOS…………..0.27
TOTAL PRECIPITATION FOR THE MONTH……….1.13  DEPARTURE……+0.11
ASOS…………..0.82
TOTAL PRECIPITATION FOR THE YEAR……….19.93  DEPARTURE……+5.09
ASOS………….21.06

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….1.0  DEPARTURE……..+0.8
TOTAL SNOWFALL FOR THE MONTH…………….2.6  DEPARTURE……..+1.5
TOTAL SNOWFALL FOR THE SEASON…………..92.8  DEPARTURE…….+31.9

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 Low temp since midnight is 34F; 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 7
HIGH 90 IN 2010
LOW 13 IN 1982
PRECIP 1.72 IN. IN 1924
SNOWFALL 4.5 IN. IN 1967, 1996
PEAK GUST 65 MPH WNW IN 1982

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

TODAY’S REPORT PREPARED BY: Benjamin Turner and Mike Iacono