Thursday, November 30, 2017

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, NOVEMBER 30, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME

COOLER TEMPERATURES RETURN AFTER AN ABOVE
SEASONABLY WARM DAY YESTERDAY….

A cold front with winds from the northwest passed
Blue Hill Observatory causing temperatures to drop
32 degrees overnight. Yesterday we had a unseasonably
warm high of 58F. This is 13 degrees above the daily
normal of 45F. The overnight minimum was 26F which is
3 degrees below the daily normal of 29F. We are back
to temperatures that are slightly below normal with
a high of 42F by 1:00 P.M. today. This is also 3
degrees below the normal daily high maximum of 45F.
The wind picked you yesterday afternoon with a peak
gust of 46 MPH from the west. Today the wind has
been light and variable, shifting to a southern
wind just after 10:00 A.M.
Cloud cover increased as pressure began to drop
throughout the day. The morning started clear
with only a few dense cirrus clouds. By 10:00 A.M.
the cirrus/ cirrostratus clouds were scattered and
finally by 1:00 P.M. the sky was overcast cirrostratus.
A distance haze kept visibility to 70 miles all day.

Today’s Observations:

7 A.M.
Weather: Clear, few dense cirrus ESE-W, patches of
cirrocumulus S-SW
Temperature: 27F; Dew Point: 20F; Wind: NW at 9 kts
Sea-level pressure: 30.36 ins. Hg, falling then rising
Visibility: 70 miles
6-hr Max temp: 33F
6-hr Min temp: 26F
24-hr precip: 0.00 ins.
BHO SA 1155 CLR 70 282/27/20/3109/036/ FEW DNS CI ESE-W
PTCHS CC S-SW/ 8/002 53015 10033 20026

10 A.M.
Weather: Scattered cirrostratus, few cirrus in all
directions
Temperature: 37F; Dew Point: 24F; Wind: S at 3 kts,
Wind: Light
Sea-level pressure: 30.35 ins. Hg, rising then falling
Visibility: 70 miles, thin smoke layer along horizon,
distant haze
3-hr precip: 0.00 ins.
BHO SA 1455 250 SCT 70 278/37/24/E1903/035/ FEW CI ALQDS
THN K LYR ALG HRZN WSW-N LGT DSNT HZ WND LGT/ 8/006 58004

1 P.M.
Weather: Overcast cirrostratus, parhelion
Temperature: 42F; Dew Point: 28F; Wind: SSE at 9 kts
Sea-level pressure: 30.26 ins. Hg, falling unsteadily
Visibility: 70 miles distant haze
6-hr Max temp: 42F
6-hr Min temp: 27F
6-hr precip: 0.00 ins.
BHO SA 1755 E250 OVC 70 247/42/28/1609/026/ PARHELION
DSNT HZ/ 8/007 56031 10042 20027

SUMMARY FOR WEDNESDAY, NOVEMBER 29, 2017

TEMPERATURE (DEGREES F)
MAX…..58   NORMAL…..45
MIN…..34   NORMAL…..29
MEAN….46   NORMAL…..37

DEPARTURE FROM 30-YEAR NORMAL………………………+9
TOTAL DEPARTURE FOR THE MONTH………………………-2 [-0.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………19  DEPARTURE……….-9
TOTAL HEATING UNITS FOR THE MONTH………..671  DEPARTURE……….+1
TOTAL HEATING UNITS FOR THE SEASON……….939  DEPARTURE……..-294
TOTAL HEATING UNITS LAST SEASON TO DATE….1016  DIFFERENCE……..-77

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….46 W   AT 2:09 P.M.
AERO……………………47 W   AT 2:10 P.M.
ASOS……………………47 WNW AT 2:10 P.M.
DAVIS…………………..45 W   AT 2:10 P.M. RMY 46
FASTEST MILE FOR YESTERDAY…………………35 W   AT 2:08 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………36 W   AT 2:11 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..37 WNW AT 2:11 P.M.
AVERAGE WIND SPEED AND DIRECTION………….17.4 SSW
ASOS………………….17.0
DAVIS…………………16.6 W   [266 DEG.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.16
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….2.04  DEPARTURE……-2.56
ASOS…………..2.00
TOTAL PRECIPITATION FOR THE YEAR……….49.84  DEPARTURE……+1.47
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/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

11/1  53/39/46/0/0.00/167/27           25 SE  AERO 24 SE  RMY 25
11/2  71/49/60/+14/0.00/000/00         28 SSE AERO 25 SSE RMY 27
11/3  74/47/61/+15/T/350/57            35 WNW AERO 35 WNW RMY 38
11/4  54/39/47/+2/0.00/545/89          31 NW  AERO 31 NW  RMY N/A
11/5  61/46/54/+9/0.01/006/01          26 S   AERO 24 S   RMY N/A
11/6  64/47/56/+11/0.05/000/00         32 S   AERO 28 SSW RMY 35
11/7  46/35/41/-4/0.11/145/24          26 NNW AERO 23 N   RMY 26
11/8  43/34/39/-5/0.08/295/49          26 N   AERO 23 N   RMY 27
11/9  50/31/41/-3/0.01/480/80          25 S   AERO 23 S   RMY N/A
11/10 45/20/33/-11/0.00/586/98         46 WNW AER0 44 WNW RMY 46
11/11 36/18/27/-16/0.00/589/99         28 WNW AERO 26 WNW RMY 28
11/12 44/27/36/-7/0.00/302/51          13 E   AERO  9 S   RMY 14
11/13 40/35/38/-5/0.26/000/00          20 NNW AERO 17 NNW RMY 20
11/14 40/33/37/-5/T/000/00             18 N   AERO 15 N   RMY 18
11/15 43/31/37/-5/0.00/417/71          20 NE  AERO 15 NE  RMY N/A
11/16 51/37/44/+2/0.21/012/02          32 SE  AERO 32 SE  RMY N/A TSTM
11/17 42/30/36/-5/0.00/565/97          41 WNW AERO 43 WNW RMY 47
11/18 49/26/38/-3/0.08/168/29          35 SSW AERO 35 SSW RMY 39
11/19 58/34/46/+5/0.36/231/40          50 W   AERO 50 W   RMY 54
11/20 39/31/35/-5/0.00/462/80          48 WNW AERO 50 WNW RMY 44
11/21 57/35/46/+6/0.00/506/88          46 SSW AERO 46 SSW RMY 48
11/22 53/35/44/+4/0.87/000/00          37 NW  AERO 38 NW  RMY 41
11/23 40/26/33/-6/0.00/571/100         26 NW  AERO 25 NW  RMY N/A
11/24 49/29/39/0/0.00/…/..           28 SSW AERO 26 SSW RMY 29
11/25 57/38/48/+9/0.00/…/..          29 SSW AERO 28 SSW RMY 31
11/26 46/33/40/+2/0.00/…/..          39 WNW AERO 41 WNW RMY 41
11/27 44/24/34/-4/0.00/…/..          37 W   AERO 39 W   RMY 36
11/28 45/19/32/-6/0.00/…/..          35 S   AERO 37 S   RMY N/A
11/29 58/34/46/+9/0.00/…/..          46 W   AERO 47 W   RMY 46

11/30 Low temp since midnight is 26F; normal low is now 29F

DAILY RECORDS FOR NOVEMBER 2017

11/10/17: DAILY RECORD LOW MINIMUM TEMPERATURE OF 20F,
TIES WITH PREVIOUS RECORD SET IN 2004

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

RECORDS FOR NOVEMBER 30
HIGH 67 IN 2006
LOW 7 IN 1887, 1929
PRECIP 2.42 INCHES IN 1944
SNOWFALL 10.2 INS IN 1945
PEAK GUST 90 SSW IN 1963

RECORDS FOR DECEMBER 1
HIGH 70 IN 2001
LOW 3 IN 1887
PRECIP 1.46 INS. IN 1917
SNOW 2.0 INS. IN 1902
PEAK GUST 72 MPH NW IN 1964

TODAY’S REPORT PREPARED BY: Kaitlin Geagan