Saturday, September 24, 2016

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, SEPTEMBER 24, 2016
ALL TIMES ARE IN EASTERN STANDARD TIME

COLD FRONT MOVES SOUTHWARD OVERNIGHT…MOSTLY SUNNY
BUT COOLER AND MUCH DRIER AIR THIS WEEKEND…

A cold front moving southward through New England on Friday
evening brought a total of 0.19 inches of rainfall overnight.
The wind direction turned out of the northeast by late
afternoon at Blue Hill and a peak gust to 32 mph NE was
observed at 7:04 PM EST. The low temperature of 51F this morning
was the lowest reading of the season so far, with much cooler
temperatures expected the next couple of nights. As of
mid-afternoon, the dew point has dropped into the middle 30s.
The visibility today has been excellent near 75-80 miles.

This week’s updated US Drought Monitor still shows no change
in the extreme drought conditions affecting most of the
state. Blue Hill Observatory is currently 1.36 inches below
normal for the month and 11.41 inches below normal for the year.

7 A.M.
Weather: Scattered altocumulus, scattered cirrus, few
stratocumulus NE-SE, few cumulus distant SW-NNW
Temperature: 53F; Dew Point: 49F; Wind: N at 7 kts
Sea-level pressure: 30.13 ins. Hg, rising, then more slowly
Visibility: 75 miles
6-hr Max temp: 54F
6-hr Min temp: 51F
24-hr precip: 0.19 in.
BHO SA 1155 65 SCT 200 SCT 75 202/53/49/3507/013/ FEW SC NE-SE
FEW CU DSNT SW-NNW/ 8/531 51010 70019 10054 20051

10 A.M.
Weather: Broken stratocumulus formed from the spreading out
of cumulus, few moderate cumulus
Temperature: 61F; Dew Point: 40F; Wind: NNW at 8 kts,
Sea-level pressure: 30.13 ins. Hg, rising slightly
Visibility: 75 miles, except 70 miles W-NNW
BHO SA 1455 E35 BKN 75 203/61/40/3408/013/ SC/CU FEW MDT CU
VSBY W-NNW 70/ 8/400 52001

1 P.M.
Weather: Scattered altocumulus
Temperature: 64F; Dew Point: 39F; Wind: NW at 8 kts,
Wind: Direction variable W-NNW
Sea-level pressure: 30.09 ins. Hg, falling, then more quickly
Visibility: 80 miles
6-hr Max. temp: 65F
6-hr Min. temp: 53F
6-hr precip: 0.00 in.
BHO SA 1755 55 SCT 80 190/64/39/3108/009/ WND 28V34/ 8/100
58013 10065 20053

SUMMARY FOR FRIDAY, SEPTEMBER 23, 2016

TEMPERATURE (DEGREES F)
MAX…..80   NORMAL…..69
MIN…..53   NORMAL…..52
MEAN….67   NORMAL…..60

DEPARTURE FROM 30-YEAR NORMAL……………………+7
TOTAL DEPARTURE FOR THE MONTH………………….+107 [+4.5 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………2   DEPARTURE……….+1
TOTAL COOLING UNITS FOR THE MONTH………….102   DEPARTURE………+48
TOTAL COOLING UNITS FOR THE SEASON…………894   DEPARTURE……..+303
TOTAL COOLING UNITS LAST SEASON TO DATE…….797   DIFFERENCE……..+97

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………0   DEPARTURE……….-6
TOTAL HEATING UNITS FOR THE MONTH……………6   DEPARTURE………-62
TOTAL HEATING UNITS FOR THE SEASON………….16   DEPARTURE………-77
TOTAL HEATING UNITS LAST SEASON TO DATE……..21   DIFFERENCE………-5

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….32 NE  AT  7:04 P.M.
ASOS……………………33 NE  AT  7:04 P.M.
DAVIS…………………..30 NE  AT  6:00 P.M. RMY 32
FASTEST MILE FOR YESTERDAY…………………23 NE  AT  6:43 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………22 NE  AT  7:05 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..20 NE  AT  8:02 P.M.
AVERAGE WIND SPEED AND DIRECTION………….11.0 NE
ASOS………………….10.4
DAVIS………………….9.3 W  [265 Deg.] * Last of several occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.19  DEPARTURE……+0.05
ASOS…………..0.19
TOTAL PRECIPITATION FOR THE MONTH……….1.66  DEPARTURE……-1.36
ASOS…………..1.66
TOTAL PRECIPITATION FOR THE YEAR……….26.63  DEPARTURE…..-11.41
ASOS………….26.93

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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

9/1  72/64/68/0/0.09/000/00                  21 NNW AERO 16 NNW RMY 20
9/2  76/58/67/-1/0.00/738/94                 23 ENE AERO 17 NE  RMY 23
9/3  72/56/64/-3/0.00/368/47                 16 E   AERO 12 E   RMY N/A
9/4  71/58/65/-2/0.00/740/95                 28 NE  AERO 21 NE  RMY 27
9/5  73/57/65/-2/0.52/241/31                 42 NNE AER0 33 NNE RMY 43
9/6  70/61/66/-1/0.54/046/06                 32 N   AERO 23 NNE RMY N/A
9/7  78/66/72/+6/0.05/339/44                 21 NE* AERO 15 NE* RMY 21
9/8  79/65/72/+6/T/276/36                    22 S   AERO 15 S   RMY 23
9/9  90/69/80/+14/T/421/55                   23 W   AERO 24 W   RMY 25
9/10 82/71/77/+12/T/229/30                   25 S   AERO 18 S   RMY 32
9/11 79/59/69/+4/0.10/365/48                 39 WNW AERO 30 WNW RMY 43
9/12 76/53/65/0/0.00/749/99                  18 SW* AERO 13 WNW RMY 19
9/13 81/57/69/+5/0.00/739/98                 25 SSW AERO  M     RMY 26
9/14 87/58/73/+9/T/526/70                    35 NNW AERO  M     RMY 35
9/15 67/52/60/-4/0.00/531/71                 21 NE  AERO  M     RMY 20
9/16 74/54/64/+1/0.00/567/76                 23 SSE AERO  M     RMY 24
9/17 77/54/66/+3/0.00/…/..                 28 S   AERO  M     RMY 28
9/18 79/63/71/+9/T/…/..                    30 SW  AERO  M     RMY 33
9/19 73/67/70/+8/0.16/…/..                 25 S   AERO  M     RMY N/A
9/20 81/66/74/+12/0.00/…/..                16 WSW*AERO  M     RMY N/A
9/21 81/64/73/+12/T/…/..                   20 WNW AERO  M     RMY 18
9/22 82/63/73/+12/0.00/…/..                23 S   AERO  M     RMY 25
9/23 80/53/67/+7/…./…/..                 32 NE  AERO  M     RMY 32

9/24 Low temp since midnight is 51F; normal low is now 52F

DAILY RECORDS FOR SEPTEMBER 2016

9/10/16: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 71F,
BREAKS PREVIOUS RECORD OF 69F SET IN 1915, 1931, AND 1989

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

RECORDS FOR SEPTEMBER 24
HIGH 87F IN 1959
LOW 33F IN 1885,1950,1963
PRECIP 1.19 INCHES IN 1955
PEAK GUST 54e MPH SW IN 1940

RECORDS FOR SEPTEMBER 25
HIGH 87F IN 1970
LOW 31F IN 1950
PRECIP 2.68 INCHES IN 1961
PEAK GUST 63 MPH SSW IN 1991

TODAY’S REPORT PREPARED BY: Mike Iacono