Wednesday, April 15, 2020

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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, APRIL 15, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

A FAIR WEATHER DAY FOLLOWING SOME RAIN IN THE
MORNING HOURS….

Today we observed 80 miles of visibility with
weather improving as the day went on. After
0.02 inches of rainfall this morning, overcast
skies became partly cloudy in the afternoon. Wind
has picked up considerably, with a max gust so far
of 36 mph from the northwest.

Despite the sunny conditions, cold air advection
from the west has kept temperatures below seasonal
averages. Our high temperature so far today is 51F,
which is 4 degrees below our daily normal high
temperature of 55F. The low since midnight is 36F,
which is a degree below the daily normal low of 37F.

PRELIMINARY STATS FOR MARCH 2020

TEMPERATURE, Deg. F
Avg. Max. 49.8 [+5.5] Avg. Min. 32.3 [+5.7] Mean      41.1 [+5.6] 24-hour corrected mean: 40.5
Max. for month: 72F on the 9th
Min. for month: 15F on the 1st

HEATING DEGREE DAYS
Total heating units:    733 [-183] Total for the season:  4873 [-611] Total for last season: 5432

PRECIPITATION, Inches
Total: 4.67 [-0.91] Greatest in 24 hrs: 2.37 ins. on the 23rd-24th

SNOWFALL, Inches
Total: 2.8 [-9.9] Greatest in 24 hrs: 1.6 ins. on the 23rd

WIND, mph
Avg. uncorrected wind speed: 12.6 mph
Avg. corrected wind speed:   12.9 mph
Prevailing wind direction:   W [12%] Peak gust and direction:     56 W on the 4th

SUNSHINE:
Campbell-Stokes card minutes: 11298 minutes of possible 21516 or 53%
Astronomical total minutes: 11708 minutes of possible 22287 or 53%

Today’s Observations:

7 A.M.
Weather: Overcast stratus
Temperature: 37F; Dew Point: 35F; Relative Humidity: 92%
Wind: NW at 4 kts, light and variable
Sea-level pressure: 29.93 ins. Hg: rising, then falling
Visibility: 80 miles
6-hr Max temp: 45F
6-hr Min temp: 36F
24-hr Precip:  0.02 ins.
24-hr Snowfall: 0.0 ins.
BHO SA 1155 E40 OVC 80 137/37/35/3204/993/ WND L/V/ 8/6// 70002
50007 10045 20036

10 A.M.
Weather: Broken altostratus, few stratus fractus
Temperature: 42F; Dew Point: 31F; Relative Humidity: 64%
Wind: NW at 8 kts
Sea-level pressure: 29.88 ins. Hg: rising, then falling
Visibility: 75 miles
3-hr Precip:  0.00 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1455 E65 BKN 75 123/42/31/3108/988/ FEW STFA ALQDS/ 8/720
56014

1 P.M.
Weather: Scattered cumulus, broken altocumulus
Temperature: 50F; Dew Point: 31F; Relative Humidity: 31%
Wind: NW at 9 kts
Sea-level pressure: 29.82 ins. Hg: falling, then more rapidly
Visibility: 80 miles
6-hr Max temp: 51F
6-hr Min temp: 37F
6-hr Precip:  0.00 ins.
6-hr Snowfall: 0.0 ins.
BHO SA 1755 65 SCT E250 BKN 80 101/50/31/3109/982/ 8/072 56022 10051
20037

SUMMARY FOR TUESDAY, APRIL 14, 2020

TEMPERATURE (DEGREES F)
MAX…..57   NORMAL…..55
MIN…..41   NORMAL…..37
MEAN….49   NORMAL…..46

DEPARTURE FROM 30-YEAR NORMAL………………..+3
TOTAL DEPARTURE FOR THE MONTH……………….+19 [+1.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………16  DEPARTURE……. -3
TOTAL HEATING UNITS FOR THE MONTH…………..281  DEPARTURE…….-19
TOTAL HEATING UNITS FOR THE SEASON…………5154  DEPARTURE……-630
TOTAL HEATING UNITS LAST SEASON TO DATE…….5684  DEPARTURE……-530

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..41 W   AT 12:57 A.M.
AERO…………………….40 W   AT 12:55 A.M
ASOS…………………….40 W   AT 12:57 A.M.
DAVIS……………………42 W   AT 12:57 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………….28 W   AT 12:58 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….26 W   AT 12:58 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………30 W   AT 12:55 A.M.
AVERAGE WIND SPEED AND DIRECTION……………10.6 WNW
ASOS……………………10.1
DAVIS…………………..10.9 WNW [287 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.02  DEPARTURE……-0.14
ASOS…………..0.02
TOTAL PRECIPITATION FOR THE MONTH……….4.92  DEPARTURE……+2.56
ASOS…………..5.10
TOTAL PRECIPITATION FOR THE YEAR……….14.25  DEPARTURE……-2.11
ASOS………….14.81

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE…….-0.1
TOTAL SNOWFALL FOR THE MONTH…………..TRACE  DEPARTURE…….-2.1
TOTAL SNOWFALL FOR THE SEASON…………..27.6  DEPARTURE……-34.2

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

03/01  33/15/24/-7/0.00/0.0/676/100        28 WNW AERO 28 WNW RMY 27
03/02  52/24/38/+7/T/T/482/71              40 S   AERO 39 S   RMY 41
03/03  64/45/55/+23/0.05/0.0/361/53        30 S   AERO 30 S   RMY N/A
03/04  50/38/44/+12/0.04/0.0/561/82        56 W   AERO 56 W   RMY 58
03/05  51/32/42/+10/0.00/0.0/666/97        31 W   AERO 31 NW  RMY 32
03/06  47/30/39/+7/0.04/0.3/283/41         46 NE  AERO 45 NE  RMY 46
03/07  43/26/35/+2/0.03/0.5/534/77         42 N   AERO 43 N   RMY 44
03/08  53/26/40/+7/0.00/0.0/508/73         31 W   AERO 30 W   RMY 28
03/09  72/40/56/+23/0.00/0.0/685/98        32 SW  AERO 32 SW  RMY 31
03/10  68/49/59/+26/0.00/0.0/246/35        48 WSW AERO 46 WSW RMY 49
03/11  56/37/47/+13/0.00/0.0/501/71        31 WNW AERO M  M   RMY 21
03/12  46/31/39/+5/0.01/0.0/156/22         21 SE  AERO 18 SE  RMY N/A
03/13  59/38/49/+15/0.20/0.0/000/00        46 WNW AERO 44 WNW RMY 46
03/14  51/35/43/+8/0.00/0.0/613/86         37 W   AERO 36 W   RMY 35
03/15  47/28/38/+3/0.00/0.0/680/95         28 NW  AERO 28 NW  RMY N/A
03/16  36/22/29/-6/0.00/0.0/618/86         21 NE  AERO 21 ESE RMY 21
03/17  43/28/36/0/0.06/0.4/000/00          29 W   AERO 30 W   RMY 29
03/18  54/31/43/+7/0.00/0.0/609/84         26 S   AERO 26 S   RMY 26
03/19  43/37/40/+4/0.63/0.0/000/00         36 E   AERO 35 E   RMY 34
03/20  66/37/52/+15/0.03/0.0/000/00        48 W   AERO 48 W   RMY 46
03/21  55/29/42/+5/0.00/0.0/535/73         45 W   AERO 48 W   RMY N/A
03/22  36/23/30/-7/0.00/0.0/692/94         23 NE  AERO 24 NE  RMY 23
03/23  40/25/33/-5/1.74/1.6/037/05         38 NNE AERO 39 NNE RMY 38
03/24  48/33/41/+3/0.63/0.0/148/20         37 NNW AERO 37 NNW RMY N/A
03/25  41/35/38/0/0.03/0.0/000/00          28 ENE AERO 28 ENE RMY 27
03/26  51/30/41/+2/0.00/0.0/613/82         25 SSE AERO 26 SSW RMY N/A
03/27  61/41/51/+12/0.00/0.0/631/84        32 NW  AERO M  M   RMY 33
03/28  56/36/46/+7/0.15/0.0/309/41         22 S   AERO 21 E   RMY N/A
03/29  43/37/40/0/0.74/0.0/000/00          32 NE  AERO 33 NE  RMY 33
03/30  40/34/37/-3/0.21/0.0/000/00         33 NE  AERO 33 NE  RMY 33
03/31  40/29/35/-6/0.08/0.0/564/74         28 ENE AERO 26 ENE RMY N/A

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

04/01  42/28/35/-6/0.00/0.0/…/..         28 NE  AERO 28 NE  RMY 30
04/02  46/35/41/0/…/0.0/…/..           39 NW  AER0 40 NW  RMY 41
04/03  42/38/40/-2/…./0.0/…/..         48 NE  AERO 53 NE  RMY 49
04/04  46/36/41/-1/…./0.0/…/..         38 NE  AERO 38 NE  RMY N/A
04/05  55/36/46/+3/T/0.0/…/..            22 S   AERO 21 S   RMY 21
04/06  61/40/51/+8/0.00/0.0/…/..         29 NW  AERO 30 NW  RMY 29
04/07  63/42/53/+10/0.00/0.0/…/..        29 W   AERO 30 W   RMY 28
04/08  50/41/46/+2/…./…/…/..         23 S   AERO 22 S   RMY 22
04/09  47/37/42/-2/…./…/…/..         58 W   AERO 58 W   RMY 56
04/10  47/35/41/-4/0.02/T/…/..           48 W   AERO 50 W   RMY 53
04/11  51/33/42/-3/0.00/0.0/…/..         38 WNW AERO 39 WNW RMY 40
04/12  60/33/47/+2/0.00/0.0/…/..         38 S   AERO 40 S   RMY N/A
04/13  59/50/55/+9/1.42/0.0/…/..         79 S   AERO 83 S   RMY 78
04/14  57/41/49/+3/0.00/0.0/…/..         41 W   AERO 40 W   RMY N/A

04/15 The low since midnight is 36F, daily normal minimum is 37F

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

RECORDS FOR APRIL 15
HIGH 81 IN 1896
LOW 23 IN 1943
PRECIP 1.75 IN. IN 2007
SNOWFALL 1.0 IN. IN 1916, 1962
PEAK GUST 66 MPH E IN 2007

RECORDS FOR APRIL 16
HIGH 89 IN 2012
LOW 23 IN 1943
PRECIP 2.45 IN. IN 1929
SNOWFALL 2.0 IN. IN 1904, 1962
PEAK GUST 73 MPH E IN 2007

TODAY’S REPORT PREPARED BY: Benjamin Turner