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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, NOVEMBER 21, 2017  
ALL TIMES ARE IN EASTERN STANDARD TIME
 
MODERATE WIND FROM THE SOUTHWEST ALLOWS
TEMPERATURES TO QUICKLY RISE ABOVE NORMAL... 

The wind shifted direction again yesterday just 
before 4:00 P.M. EST from the WNW-WSW. Today wind
has been coming from the SW-SSW, this caused 
temperatures to rise above normal and we observed
a maximum high of 57F by 1:00 P.M. EST. This is an 
18 degree increase since yesterday's unseasonably 
cool maximum temperature of 39F. This is also a
20 degree increase since the 7:00 A.M. EST 
observed temperature of 37F. 
The SW-SSW wind has overall decreased since yesterday 
but has still remained moderate frequently gusting 
over 32 kts (37 MPH) in the afternoon. Yesterday we 
had a peak gust of 42 kts (46 MPH). So far today
we have had a peak gust of 36 kts (41 MPH) by 1:00 
P.M. EST. Sky remained mostly clear and sunny with 
cirrus clouds at each observation. Visibility 
increased from 40 miles at 7:00 A.M. EST to 70 miles
with a lingering haze at the other observation times. 
It was also a fairly dry day with humidity dropping
from 68% down to 31% by 1:00 P.M. 

Today's Observations:

7 A.M.
Weather: Scattered cirrus
Temperature: 37F; Dew Point: 27F; Wind: SSW at 15 kts
Sea-level pressure: 30.11 ins. Hg, falling then rising   
Visibility: 40 miles, distant fog in all directions
6-hr Max temp: 37F
6-hr Min temp: 35F
24-hr precip: 0.00 ins.
BHO SA 1155 250 SCT 40 197/37/27/2015/011/ DSNT FG ALQDS/ 
8/001 53001 10037 20035

10 A.M.
Weather: Scattered cirrus 
Temperature: 49F; Dew Point: 28F; Wind: SSW at 17G25 kts,
Peak Wind: 27 kts (31 MPH) SSW at 9:27 A.M. EST
Sea-level pressure: 30.12 ins. Hg, rising then falling  
Visibility: 70 miles, distant haze ESE-W 
3-hr precip: 0.00 ins. 
BHO SA 1455 250 SCT 70 200/49/28/2017G25/012/ DSNT HZ ESE-W 
PK WND 2027/27/ 8/001 50003 

1 P.M.
Weather: Clear, few cirrus in all directions
Temperature: 57F; Dew Point: 28F; Wind: SSW at 20G31 kts,
Peak Wind: 36 kts (41 MPH) SSW at 12:02 P.M. EST
Sea-level pressure: 30.05 ins. Hg, falling, then more slowly 
Visibility: 70 miles, distant haze ESE-WNW 
6-hr Max temp: 57F
6-hr Min temp: 37F 
6-hr precip: 0.00 ins. 
BHO SA 1755 CLR 70 175/57/28/2020G31/005/ FEW CI ALQDS 
DSNT HZ ESE-WNW PK WND 2036/02/ 8/001 56025 10057 20037 

SUMMARY FOR MONDAY, NOVEMBER 20, 2017
 
TEMPERATURE (DEGREES F)
MAX.....39   NORMAL.....49
MIN.....31   NORMAL.....32
MEAN....35   NORMAL.....40

DEPARTURE FROM 30-YEAR NORMAL..........................-5
TOTAL DEPARTURE FOR THE MONTH.........................-16 [-1.0 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY............30   DEPARTURE..........+5
TOTAL HEATING UNITS FOR THE MONTH...........448   DEPARTURE.........+16
TOTAL HEATING UNITS FOR THE SEASON..........716   DEPARTURE........-279
TOTAL HEATING UNITS LAST SEASON TO DATE.....772   DIFFERENCE........-56

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................48 WNW AT  9:19 A.M. 
                   AERO........................50 WNW AT  9:19 A.M.
                   ASOS........................50 W   AT  9:20 A.M.
                   DAVIS.......................51 W   AT  9:19 A.M. RMY 44
FASTEST MILE FOR YESTERDAY.....................31 WNW AT  9:19 A.M.    
MAXIMUM 2-MINUTE ASOS AVERAGE..................31 W   AT 12:32 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE.................32 WNW AT  9:07 A.M.
AVERAGE WIND SPEED AND DIRECTION.............17.2 W
                   ASOS......................15.9
                   DAVIS.....................16.3 W [279 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..........1.17  DEPARTURE......-1.98 
                         ASOS..............1.11
TOTAL PRECIPITATION FOR THE YEAR..........48.97  DEPARTURE......+2.05
                         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/.../..          25 S   AERO 23 S   RMY N/A 
11/10 45/20/33/-11/0.00/.../..         46 WNW AER0 44 WNW RMY 46 
11/11 36/18/27/-16/0.00/.../..         28 WNW AERO 26 WNW RMY 28 
11/12 44/27/36/-7/0.00/.../..          13 E   AERO  9 S   RMY 14
11/13 40/35/38/-5/..../.../..          20 NNW AERO 17 NNW RMY 20
11/14 40/33/37/-5/..../.../..          18 N   AERO 15 N   RMY 18
11/15 43/31/37/-5/0.00/.../..          20 NE  AERO 15 NE  RMY N/A
11/16 51/37/44/+2/..../.../..          32 SE  AERO 32 SE  RMY N/A TSTM
11/17 42/30/36/-5/0.00/.../..          41 WNW AERO 43 WNW RMY 47
11/18 49/26/38/-3/..../.../..          35 SSW AERO 35 SSW RMY 39
11/19 58/34/46/+5/..../.../..          50 W   AERO 50 W   RMY 54
11/20 39/31/35/-5/0.00/../..           48 WNW AERO 50 WNW RMY 44 

11/21 Low temp since midnight is 35F; normal low is now 32F

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 21
HIGH 69 IN 1931
LOW 10 IN 1888
PRECIP 2.60 INCHES IN 1950
SNOWFALL 4.0 INS IN 1929
PEAK GUST 69 NW IN 1989

RECORDS FOR NOVEMBER 22
HIGH 70 IN 1931
LOW 12 IN 1987
PRECIP 1.78 INS IN 2005
SNOWFALL 9.0 INS IN 1971
PEAK GUST 70e SE IN 1945

TODAY'S REPORT PREPARED BY: Kaitlin Geagan

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