Saturday, April 21, 2018
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, APRIL 21, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME
VERY SUNNY AND WARMER TODAY…
The low temperature of the day so far of 33F was
seven degrees cooler than the normal minimum temperature
for this date. By early afternoon, the temperature had
climbed to the upper 50s, which is very close to the
normal high for this time of year. The sky was completely
free of clouds after sunrise, and it remained very sunny
all day with only a few cumulus forming later in the
morning. The dew point dropped from the upper 20’s to
the lower 20’s during the day as drier air moved into
the area. It has been a little breezy today with a peak
gust to 28 mph from the NW at 8:58 AM. Visibility has
been very good at 75 miles all day.
Today’s Observations:
7 A.M.
Weather: Clear (SKC), no clouds
Temperature: 40F; Dew Point: 28F; Wind: NW at 10 kts,
Sea-level pressure: 30.30 ins. Hg, rising, then more quickly
Visibility: 75 miles
6-hr Max temp: 40F
6-hr Min temp: 33F
24-hr precip: 0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1155 CLR 75 261/40/28/3110/030/ SKC/ 53014 10040 20033
10 A.M.
Weather: Clear, few cumulus and cumulus fractus all quadrants
Temperature: 50F; Dew Point: 22F; Wind: NW at 14G22 kts,
Sea-level pressure: 30.28 ins. Hg, falling, then more rapidly
Visibility: 75 miles
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins.
BHO SA 1455 CLR 75 254/50/22/3114G22/028/ FEW CU/CUFRA ALQDS/
8/100 58007
1 P.M.
Weather: Clear, few cumulus and cumulus fractus all quadrants
Temperature: 56F; Dew Point: 21F; Wind: NW at 10 kts,
Sea-level pressure: 30.23 ins. Hg, falling, then more rapidly
Visibility: 75 miles
6-hr Max temp: 56F
6-hr Min temp: 40F
6-hr precip: 0.00 ins.
6-hr snowfall: 0.00 ins.
Snow depth: 0 ins.
BHO SA 1755 CLR 75 237/56/21/3010/023/ FEW CU/CUFRA ALQDS/
8/100 58017 10056 20040
SUMMARY FOR FRIDAY, APRIL 20, 2018
TEMPERATURE (DEGREES F)
MAX…..52 NORMAL…..58
MIN…..31 NORMAL…..40
MEAN….42 NORMAL…..49
DEPARTURE FROM 30-YEAR NORMAL………………………-7
TOTAL DEPARTURE FOR THE MONTH……………………..-93 [-4.9 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….23 DEPARTURE……….+6
TOTAL HEATING UNITS FOR THE MONTH…………497 DEPARTURE………+92
TOTAL HEATING UNITS FOR THE SEASON……….5555 DEPARTURE……..-334
TOTAL HEATING UNITS LAST SEASON TO DATE…..5216 DIFFERENCE…….+339
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….34 NW AT 5:12 P.M.
AERO……………………33 NW AT 4:55 P.M. *
ASOS……………………36 NW AT 10:40 A.M.
DAVIS…………………..36 M ** RMY 36
FASTEST MILE FOR YESTERDAY…………………27 NW AT 5:18 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………26 NW AT 5:19 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..27 M AT 4:17 P.M.**
AVERAGE WIND SPEED AND DIRECTION………….16.8 NW
ASOS………………….15.9
DAVIS…………………15.6 M **
* Last of several occurrences
** Davis direction malfunctioning
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00 DEPARTURE……-0.14
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….4.32 DEPARTURE……+1.11
ASOS…………..4.48
TOTAL PRECIPITATION FOR THE YEAR……….23.12 DEPARTURE……+6.09
ASOS………….24.72
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……..-0.1
TOTAL SNOWFALL FOR THE SEASON…………..92.8 DEPARTURE…….+30.3
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
* : Estimated data
4/01 58/33/46/+5/0.00/0.0/336/44 45 SSW AERO 43 SSW RMY N/A
4/02 38/30/34/-7/0.13/1.6/077/10 20 SSW AERO 15 SSW RMY 17
4/03 48/30/39/-3/…./0.0/238/31 28 SSE AERO 25 SSE RMY 25
4/04 54/36/45/+3/…./0.0/000/00 56 WNW AERO 56 WNW RMY 54
4/05 40/27/34/-9/0.00/0.0/760/98 53 WNW AERO 53 WNW RMY 52
4/06 41/25/33/-10/0.25/1.0/156/20 37 S AERO 36 S RMY 38
4/07 46/32/35/-4/0.00/0.0/312/40 32 WNW AERO 35 WNW RMY 34
4/08 41/29/35/-9/0.00/0.0/290/37 35 WNW*AERO 31 WNW RMY 34
4/09 45/24/35/-9/0.00/0.0/715/01 28 WNW*AERO 25 WNW RMY 29
4/10 39/31/35/-10/T/T/000/00 14 SSW AERO 13 SSW RMY N/A
4/11 48/29/39/-6/T/0.0/364/46 24 SSE AERO 23 SSE RMY 25
4/12 61/33/47/+2/0.03/0.0/…/.. 39 SSW AERO 38 SSW RMY 41
4/13 65/47/56/+10/T/0.0/…/.. 37 SSW AERO 37 SSW RMY N/A
4/14 51/36/44/-2/0.00/0.0/…/.. 33 ENE AERO 31 ENE RMY N/A
4/15 36/30/33/-14/…./T/…/.. 39 ENE AERO 39 ENE RMY N/A
4/16 55/32/44/-3/…./…/.. 41 ENE AERO 43 ENE RMY 41
4/17 48/36/42/-5/0.00/0.0/…/.. 37 W AERO 33 W RMY 37
4/18 53/32/43/-5/…./0.0/…/.. 35 W AERO 31 W RMY 34
4/19 41/34/38/-10/0.22/T/…/.. 28 WNW AERO 25 WNW RMY N/A
4/20 52/31/42/-7/0.00/0.0/…/.. 34 NW AERO 33 NW RMY 36
4/21 Low temp since midnight is 33F; normal low is now 40F
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
RECORDS FOR APRIL 21
HIGH 85 IN 1923
LOW 22 IN 1908
PRECIP 3.18 IN. IN 1991
SNOWFALL 0.8 IN. IN 1947
PEAK GUST 76e MPH NE IN 1940
RECORDS FOR APRIL 22
HIGH 85 IN 1977, 2001
LOW 26 IN 1981
PRECIP 1.85 IN. IN 2000
SNOWFALL 3.0 IN. IN 1940
PEAK GUST 68e MPH NW IN 1945
TODAY’S REPORT PREPARED BY: Mike Iacono
