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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, OCTOBER 19, 2015  
ALL TIMES ARE IN EASTERN STANDARD TIME

COLDEST READING OF THE SEASON SO FAR, WITH OVERNIGHT
LOW OF 26F ON GREAT BLUE HILL

A solid freeze was underway for a second consecutive night
as temperatures slid below the freezing mark by 8:00 PM EST
last evening. Just after 6:00 AM EST this morning, temperatures
bottomed out at a low of 25.8. Yesterday's maximum reading
was just 45F, some 15 degrees below the 'normal' high for
the day. 

Very clear conditions aside from a few stratocumulus distant
offshore allowed for excellent visibility when coupled with
the clear, cold air rushing in from the north. Visibility of
80 plus miles in all directions were noted at the 7:00 AM EST
observation. By the 1:00 PM EST observation conditions were
largely similar to earlier this morning with a few stratocumulus
offshore and traces of cirrus distant to the S to WNW. Visibility
was still at 80 miles in all directions and a maximum temperature
by the observation was just 45F.  


Today's Observations:

7 A.M.
Weather: Clear, few stratocumulus distant offshore NE-SSW
Temperature: 28F; Dew Point: 22F; Wind: NW at 8 kts,
Sea-level pressure: 30.45 ins. Hg, rising, then more quickly
Visibility: 80 miles
6-hr Max temp: 28F 
6-hr Min temp: 26F
24-hr precip: 0.00 ins.
BHO SA 1155 CLR 80 311/28/22/3208/045/ 
FEW SC DSNT OFFSHR NE-SSW/ 8/500 10028 20026 

10 A.M.
Weather: Clear, few stratocumulus distant offshore
NE-S, few cirrus distant WSW-NW
Temperature: 39F; Dew Point 15F; Wind: estimated WNW at 6 kts, 
Sea-level pressure: 30.45 ins. Hg, rising, then falling but higher still
Visibility: 80 miles 
BHO SA 1455 CLR 80 313/39/15/E3006/045/ 
FEW SC DSNT OFFSHR NE-S FEW CI DSNT WSW-NW WND LGT/ 8/501 50002

1 P.M.
Weather: Clear, few stratocumulus distant offshore ENE-SE,
few cirrus distant S-WNW
Temperature: 44F; Dew Point 19F; Wind: SW at 9 kts, 
Sea-level pressure: 30.37 ins. Hg, falling then more quickly
Visibility: 80 miles
BHO SA 1755 CLR 80 286/44/19/2308/037/ 
FEW SC DSNT OFFSHR ENE-SE FEW CI DSNT S-WNW/ 8/501 58027 10045 20028


SUMMARY FOR SUNDAY, OCTOBER 18, 2015 
  
TEMPERATURE (DEGREES F)
MAX.....45   NORMAL.....60 
MIN.....28   NORMAL.....42 
MEAN....37   NORMAL.....51 
 
DEPARTURE FROM 30-YEAR NORMAL......................-14
TOTAL DEPARTURE FOR THE MONTH......................-10  [-0.7 DEGREES/DAY]
 
COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............0   DEPARTURE...........0
TOTAL COOLING UNITS FOR THE MONTH...............0   DEPARTURE..........-5
TOTAL COOLING UNITS FOR THE SEASON............810   DEPARTURE........+208
TOTAL COOLING UNITS LAST SEASON TO DATE.......595   DIFFERENCE.......+215

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............28   DEPARTURE.........+14
TOTAL HEATING UNITS FOR THE MONTH.............210   DEPARTURE..........+4
TOTAL HEATING UNITS FOR THE SEASON............253   DEPARTURE.........-95
TOTAL HEATING UNITS LAST SEASON TO DATE.......243   DIFFERENCE........+10
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY...................24   NNW AT   2:36 P.M. 
                   ASOS........................27   NNW AT   2:50 P.M.  
                   DAVIS.......................24   NNW AT   2:49 P.M. RMY 25
FASTEST MILE FOR YESTERDAY.....................19   NNW AT   2:34 P.M.  
MAXIMUM 2-MINUTE ASOS AVERAGE..................18   NW  AT   2:50 P.M.    
MAXIMUM 2-MINUTE DAVIS AVERAGE.................16   NNW AT   2:33 A.M.   
AVERAGE WIND SPEED AND DIRECTION.............10.8 NNW 
                   ASOS......................10.6    
                   DAVIS......................8.9 NNW [335 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...........1.06  DEPARTURE.....-1.62
                         ASOS...............1.04
TOTAL PRECIPITATION FOR THE YEAR...........35.20  DEPARTURE.....-6.56  
                         ASOS................N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR OCTOBER CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY 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

10/1  55/51/53/-4/..../000/00               39 NE  RMY N/A
10/2  51/47/49/-8/..../000/00               40 NE  RMY 43 
10/3  51/45/48/-8/..../000/00               38 NE  RMY N/A 
10/4  55/49/52/-4/0.00/474/68               35 E   RMY 40
10/5  59/46/53/-3/T/125/18                  21 NE  RMY 20 
10/6  68/43/56/+1/0.00/663/96               17 NW  RMY 17
10/7  69/46/58/+3/0.00/640/93               20 W   RMY 20
10/8  63/49/56/+2/0.00/678/99               21 S   RMY N/A
10/9  68/50/59/+5/0.27/.../..               45 S   RMY 49
10/10 59/44/53/-2/0.00/.../..               33 NNW RMY N/A 
10/11 67/46/57/+4/0.00/.../..               26 SW  RMY 28
10/12 76/50/63/+10/0.00/.../..              22 SSW RMY 24
10/13 70/55/63/+10/0.27/.../..              23 S   RMY 24
10/14 66/46/56/+4/0.00/.../..               26 W   RMY 29
10/15 60/41/51/-1/0.00/.../..               20 SW  RMY 27
10/16 60/44/52/+1/T/.../..                  31 W   RMY 34
10/17 54/35/45/-6/T/.../..                  30 WNW RMY 33
10/18 45/28/37/-14/0.00/.../..              24 NNW RMY 25

10/19 low since midnight is 26F; normal low is now 42F  

DAILY RECORDS FOR OCTOBER 2015

-NONE SO FAR.

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

RECORDS FOR OCTOBER 19
HIGH 81F IN 1945
LOW 21F IN 1922
PRECIP 3.64 INCHES IN 1932
SNOWFALL 1.0 INCHES IN 1972
PEAK GUST 66 MPH SSW IN 1967

RECORDS FOR OCTOBER 20
HIGH 78F IN 1965,1984
LOW 24F IN 1972
PRECIP 7.10 INCHES IN 1996 (RECORD FOR MONTH)
SNOWFALL TRACE IN 1934,1943
PEAK GUST 63 MPH W IN 1966

TODAY'S REPORT PREPARED BY: Brian Fitzgerald