Saturday, April 28, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, APRIL 28, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

ABOVE SEASONABLE TEMPERATURES AND LOW HUMIDITY ON GREAT
BLUE HILL TODAY…

This morning began with foggy conditions extending from
the S-NNW with visibility at 40 miles. Clear conditions
from NNW-S with visibility at 60 miles. Cloud cover decreased
throughout the day with partly cloudy skies in the morning to
nearly clear skies in the afternoon. Dew point stayed fairly
regular at 49F with a slight drop in the afternoon to 41F.
With a stable dew point, the temperature climbed from 51F at
7am EST to 70F at 1pm EST, making today 9F above the daily
normal. Winds were light and variable today, mainly coming
out of the southwest.

Today’s Observations:

7 A.M.
Weather: Scattered stratus fractus, Scattered stratocumulus
Temperature: 51F; Dew Point: 49F; Wind: SW at 7 kts
Sea-level pressure: 29.81 ins. Hg, rising, then more slowly
Visibility: 60 miles, except S-NNW 40 miles
6-hr Max temp: 51F
6-hr Min temp: 47F
24-hr precip:  0.55 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1155 10 SCT 20 SCT 60 095/51/49/2307/981/ VSBY
S-NNW 40 DSNT FG ALQDS/ 8/500 51016 MANUAL 70055 ASOS
70055 10051 20047

10 A.M.
Weather: Scattered cumulus
Temperature: 60F; Dew Point: 49F; Wind: SW at 5 kts,
Wind: Light
Sea-level pressure: 29.84 ins. Hg, rising then, more slowly
Visibility: 60 miles
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins.
BHO SA 1455 20 SCT 60 104/60/49/2305/984/ WND LGT/ 8/100 51009

1 P.M.
Weather: Scattered cumulus, scattered cirrostratus
Temperature: 70F; Dew Point: 41F; Wind: SW at 6 kts,
Wind: Light
Sea-level pressure: 29.83 ins. Hg, falling, then rising
Visibility: 70 miles
6-hr Max temp: 70F
6-hr Min temp: 51F
6-hr precip:   0.00 ins
6-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1755 40 SCT 200 SCT 70 103/70/41/2306G16/983/
WND LGT/ 8/105 55001 10070 20051

SUMMARY FOR FRIDAY, APRIL 27, 2018

TEMPERATURE (DEGREES F)
MAX…..60   NORMAL…..60
MIN…..45   NORMAL…..42
MEAN….53   NORMAL…..51

DEPARTURE FROM 30-YEAR NORMAL………………………+2
TOTAL DEPARTURE FOR THE MONTH……………………..-81 [-3.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….12   DEPARTURE……….-2
TOTAL HEATING UNITS FOR THE MONTH…………590   DEPARTURE………+79
TOTAL HEATING UNITS FOR THE SEASON……….5648   DEPARTURE……..-347
TOTAL HEATING UNITS LAST SEASON TO DATE…..5320   DIFFERENCE…….+328

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….18 W AT 12:14 A.M.*
AERO……………………15 W AT 12:21 A.M.
ASOS……………………19 W AT 12:07 A.M.
DAVIS…………………..17 M AT 12:06 A.M.** RMY N/A
FASTEST MILE FOR YESTERDAY…………………15 W AT 12:05 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………15 W AT 12:07 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..12 M AT 12:06 A.M.**
AVERAGE WIND SPEED AND DIRECTION…………..6.6 ENE
ASOS…………………..7.1
DAVIS………………….6.3 M **
*  Last of multiple occurrences
** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.55  DEPARTURE……+0.42
ASOS…………..0.55
TOTAL PRECIPITATION FOR THE MONTH……….6.09  DEPARTURE……+1.93
ASOS…………..6.28
TOTAL PRECIPITATION FOR THE YEAR……….24.89  DEPARTURE……+6.91
ASOS………….26.52

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE………0.0
TOTAL SNOWFALL FOR THE MONTH…………….2.6  DEPARTURE……..-0.3
TOTAL SNOWFALL FOR THE SEASON…………..92.8  DEPARTURE…….+30.1

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 60/33/47/-2/0.00/0.0/…/..   28 NW  AERO 26 NW  RMY 29
4/22 61/36/49/0/0.00/0.0/…/..    25 NW  AERO 24 NW  RMY 26
4/23 62/40/51/+1/0.00/0.0/…/..   25 S   AERO 25 S   RMY 26
4/24 67/39/53/+3/0.00/0.0/…/..   31 S   AERO 29 S   RMY 32
4/25 57/47/52/+2/…./0.0/…/..   32 SE  AERO 32 SE  RMY 33
4/26 66/48/57/+6/…./0.0/…/..   36 WNW AERO 35 WNW RMY 37
4/27 60/45/53/+2/…./0.0/…/..   18 W   AERO 15 W   RMY N/A

4/28 Low temp since midnight is 47F; normal low is now 42F

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

RECORDS FOR APRIL 28
HIGH 92 IN 1990, 2009
LOW 26 IN 1947
PRECIP 2.41 IN 1904
SNOWFALL 10.0 IN. IN 1987
PEAK GUST 69 MPH NE 1967

RECORDS FOR APRIL 29
HIGH 85 IN 1974
LOW 26 IN 1909
PRECIP 1.65 IN 1923
SNOWFALL 1.0 IN. IN 1987
PEAK GUST 55 MPH WNW IN 2010

TODAY’S REPORT PREPARED BY: K.Geagan and D.Richardt