Tuesday, April 13, 2021

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

TUESDAY, APRIL 13, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0506E
SUNSET:  1824E

CLOUDS FINALLY BREAK TO ALLOW SOME SUNSHINE, BUT BRISK
NORTHEAST WIND KEEPING TEMPERATURES COOL…

The overcast sky of this morning has finally broken to
allow for some sunshine early this afternoon. Despite
the sun, a brisk northeast to east-northeast wind is
keeping temperatures on the cool side.

Visibility has been decent however averaging about 60 miles
today.

The high so far today is 55F, this is equal to the normal
high of 55F. The low since midnight is 37F, which is equal
to the daily normal low of 37F.


Today’s Observations:

7 A.M.
Weather: Scattered Stratocumulus, broken Altocumulus,
thin broken Cirrus
Temperature: 45F; Dew Point: 36F; Relative Humidity: 70%
Wind: NNE at 11G23 kts
Sea-level pressure: 30.01 in Hg, rising, then more slowly  
Visibility: 60 miles
6-hr Max temp: 45F
6-hr Min temp: 38F
24-hr Precip: 0.04 ins.
24-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1155 25 SCT E55 BKN 250 -BKN 60 163/45/36/0211G23/001/
8/571 51014 70004 10045 20038

10 A.M.
Weather: Overcast stratocumulus
Temperature: 49F; Dew Point: 37F; Relative Humidity: 62%
Wind: NE @ 14G23 kts, peak wind NE 31 mph at 9:03 A.M.
Sea-level pressure: 30.04 in Hg; rising, then more slowly
Visibility: 60 miles
3-hr Precip: 0.00 ins.
3-hr Snow: 0.0 ins.
BHO SA 1455 E35 OVC 60 174/49/37/0414G23/004/ PK WND 0427/03/
8/5// 51011

1 P.M.
Weather: Scattered stratocumulus, scattered altocumulus
Temperature: 54F, Dew point: 38F; Relative Humidity: 54%
Wind: ENE @ 12G20 kts
Sea-level pressure: 30.04 in Hg; rising, then falling
Visibility: 60 miles
6-hr Max temp: 55F
6-hr Min temp: 45F
6-hr Precip: 0.00 ins.
6-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1755 35 SCT 75 SCT 60 172/54/38/0612G20/004/ 8/570 58002
10055 20045


SUMMARY FOR MONDAY, APRIL 12, 2021

TEMPERATURE (DEGREES F)
MAX…….46     NORMAL…..54
MIN…….37     NORMAL…..36
MEAN……42     NORMAL…..45

DEPARTURE FROM 30-YEAR (1981-2010) NORMAL……. -3
TOTAL DEPARTURE FOR THE MONTH……………….+42 [+3.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………23  DEPARTURE…… +3
TOTAL HEATING UNITS FOR THE MONTH…………..220  DEPARTURE……-42
TOTAL HEATING UNITS FOR THE SEASON…………5042  DEPARTURE…..-704
TOTAL HEATING UNITS LAST SEASON TO DATE…….5128  DEPARTURE……-86

PEAK WIND GUST (MPH):
                     420C/Official…………..36 ENE @  9:39 A.M.
                     AEROVANE (south tower)…..37 ENE @  9:21 A.M.
                     ASOS…………………..36 ENE @ 11:38 A.M.
                     DAVIS #1……………….36 E   @ 11:37 A.M.
                     DAVIS #2 (south tower)…..35 ENE @  9:21 A.M.
                     RMY……………………41     @ 11:36 A.M.
                     VECTOR…………………41     @ 11:37 A.M.
                     MERLIN…………………35

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………25 ENE @ 11:16 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….24 ENE @ 11:38 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………26 E   @ 11:37 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………26 ENE @ 12:07 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..23 ESE @ 12:04 P.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE……………..24     @ 11:35 A.M.

AVERAGE WIND SPEED AND DIRECTION:
                     CONTACTING/OFFICIAL…….12.2 ENE [293 total miles]                     ASOS………………….12.0  
                     DAVIS #1………………12.6 ENE  
                     DAVIS #2………………12.7 ENE
                     RMY…………………..11.6 E
                     VECTOR………………..12.1

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.04  DEPARTURE….-0.12
                             ASOS………….0.04
TOTAL PRECIPITATION FOR THE MONTH………….0.94  DEPARTURE….-1.08
                             ASOS………….0.92
TOTAL PRECIPITATION FOR THE YEAR………….11.11  DEPARTURE….-4.90
                              ASOS………..11.43

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HOURS ENDING 7 A.M………..0.0  DEPARTURE…. -0.1
TOTAL SNOWFALL FOR THE MONTH …………….TRACE  DEPARTURE…..-1.9
TOTAL SNOWFALL FOR THE SEASON……………..72.6  DEPARTURE….+11.5


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   56/30/43/+2/0.89/T/…/..        44 NW   AERO 51 NW   RMY 49
04/02   37/24/31/-10/0.00/0.0/…/..     28 NW   AERO 32 NNW  RMY 30
04/03   48/23/36/-6/0.00/0.0/…/..      24 NW   AERO 25 NW   RMY 26
04/04   58/33/46/+4/0.00/0.0/…/..      38 NNW  AERO 41 NNW  RMY 41
04/05   57/41/49/+6/T/T/…/..           41 NNW  AERO 48 NNW  RMY 50
04/06   61/40/51/+8/0.00/0.0/…/..      26 NNW  AERO 25 NNW  RMY 31
04/07   57/41/49/+6/0.00/0.0/…/..      23 ENE  AERO 21 ENE  RMY 22
04/08   59/43/51/+7/0.00/0.0/…/..      22 ENE  AERO 22 ENE  RMY 24
04/09   69/42/56/+12/0.00/0.0/…/..     24 S    AERO  M   M  RMY 26
04/10   75/43/59/+14/0.00/0.0/…/..     26 SSW  AERO 28 SSW  RMY 30
04/11   53/40/47/+2/T/0.0/…/..         33 ENE  AERO 33 ENE  RMY 34
04/12   46/37/42/-3/0.05/0.0/…/..      36 ENE  AERO 37 ENE  RMY 41

04/13   The low since midnight is 37F, the daily normal low is 37F


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

RECORDS FOR APRIL 13
HIGH 85 IN 1945
LOW 22 IN 1939
PRECIP 2.51 IN. IN 2004
SNOWFALL 6.8 IN. IN 1933
PEAK GUST 79 MPH S IN 2020

RECORDS FOR APRIL 14
HIGH 80 IN 1945
LOW 21 IN 1923
PRECIP 1.86 IN. IN 1935
SNOWFALL 8.4 IN. IN 1953
PEAK GUST 71e MPH W IN 1943

TODAY’S REPORT PREPARED BY: Matt Douglas