Wednesday, October 2, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, OCTOBER 2, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

WARM BUT NOT RECORD WARM TODAY
DRY SPELL CONTINUES;
SEPTEMBER FINISHES ON THE COOL AND SLIGHTLY DRY SIDE

Temperatures were rising to the upper 70’s under bright
sunshine and increasingly gusty W winds early this
afternoon.  The high will be well short of the record
for  this date of 85 degrees.

The sky has been mostly sunny today, with the only clouds of note well
off to our east.  Winds have finally departed from the recent, persistent
N-NE flow.  The direction today has primarily been from the WNW.  The change
in wind direction, relatively calm conditions, and plentiful sunshine have
helped push the afternoon high into the mid 70s.  Consequently, today’s
average temperature will likely finish a few degrees above the 30-year
normal for the date.

The streak of dry weather continues.  The last measurable rainfall
occurred nearly 10 days ago on September 22.  From September 3 through
October 1, rainfall has only amounted to 1.16 inches, which is only 29%
of the 30-year normal for this period.

A list of current record high temperatures is shown below in anticipation
of possible near record warmth this week.

OCTOBER 2  85F IN 1968
OCTOBER 3  82F IN 1922
OCTOBER 4  84F IN 2007

SEPTEMBER 2013 PRELIMINARY STATISTICS:
(departures relative to 1981-2010 average)

TEMPERATURE:
Average Max Temp: 71.7F [+0.1F] Average Min Temp: 52.5F [-2.1F] Mean Temp: 62.1F [-1.0F] 24-hr. Corr. Mean Temp: 61.9F [-0.2F] Max Temp: 93F on 11th
Min Temp: 40F on 17th and 24th

Total heating degree day units (month):  134 [+17] *NCDC method
Total heating degree day units (season): 146  [+4] *start July 1 (NCDC)
Total cooling degree day units (month):   56  [-4] *NCDC method
Total cooling degree day units (season): 696 [+99] *start Jan 1 (NCDC)

PRECIPITATION:
Total precipitation: 3.91 inches [-0.15 inch] Greatest 24-hr precipitation: 2.44 inches on 1st/2nd

WIND:
Avg wind speed: 10.0 MPH
Avg corrected wind speed: 10.6 MPH
Prevailing wind direction: W [12%] Peak gust: 38 MPH S on 22nd
Peak fastest mile: 30 MPH S on 21st

SUNSHINE:
Total astronomical minutes: 14488 (241.5 hrs.)
out of possible 22440 minutes (374.0 hrs) or 65%

Total Campbell Stokes card minutes; 13944 (232.4 hrs.
out of possible 21502 (358.4 hrs.) or 65%

Today’s Observations:

7 A.M.
Weather: Scattered altocumulus, altocumulus lenticularis (clouds to
the W-NE)
Temperature: 58F; Dew Point: 54F; Wind: W at 12 kts.
Sea-level pressure: 29.92 ins. Hg, rising slightly
Visibility: 20 miles, thin fog all quadrants
6-hour min. temp: 56F
BHO SA 1155 120 SCT 20 131/58/54/2612/992/ AC/ACSL W-NE THN F ALQDS/
8/040 53005 10060 20056

10 A.M.
Weather: Clear, small patch altocumulus castellanus extending
WSW-NW-NNE, small patch altocumulus lenticularis SE-SSE,
dark smoke layer along and above horizon SW-NW-NE, estimated
top 2 thousand feet
Temperature: 71F; Dew Point: 57F; Wind: WSW at 10 kts.
Wind: Direction variable SSW-W
Sea-level pressure: 29.90 ins. Hg, falling slightly
Visibility: 25 miles, hazy
BHO SA 1455 CLR 25 126/71/57/2410/990/ SML PTCH ACC XTDNG WSW-NE-NNE
SML PTCH ACSL SE-SSE DRK K LYR ALG/ABV HRZN SW-NW-NE ESTMTD TOP
TWO THSND HAZY ALQDS/ 8/080 58005

1 P.M.
Weather: Clear, small cumulus forming SW-NNW, thin smoke layer
along/above horizon W-N-E, estimated top 35 hundred feet
Temperature: 77F; Dew Point: 57F; Wind: W at 15G23 kts,
Sea-level pressure: 29.87 ins. Hg, decreasing then more rapidly
Visibility: 25 miles, hazy
6-hour max. temp: 77F
BHO SA 1755 CLR 25 116/77/57/2815G23/987/ SML CU FRMG SW-NNW
THN K LYR ALG HRZN/ABV ESTMTD TOP 35 HND HAZY ALQDS/
8/100 58010 10077 20058

WEATHER SUMMARY FOR MONDAY, OCTOBER 1, 2013

TEMPERATURE (DEGREES F)
MAX…..75    NORMAL…..66
MIN…..50    NORMAL…..49
MEAN….63    NORMAL…..57

DEPARTURE FROM 30-YEAR NORMAL…………………+6
TOTAL DEPARTURE FOR THE MONTH…………………+6 [+6.0 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..0   DEPARTURE………-1
TOTAL COOLING UNITS FOR THE MONTH…………..0   DEPARTURE………-1
TOTAL COOLING UNITS FOR THE SEASON………..696   DEPARTURE……..+99
TOTAL COOLING UNITS LAST SEASON TO DATE……765   DIFFERENCE…….-69

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..2   DEPARTURE………-6
TOTAL HEATING UNITS FOR THE MONTH…………..2   DEPARTURE………-2
TOTAL HEATING UNITS FOR THE SEASON………..148   DEPARTURE………-3
TOTAL HEATING UNITS LAST SEASON TO DATE……107   DIFFERENCE…….+41

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………16 WNW AT  2:41 P.M. *
AERO…………………..16 WNW at  2:41 p.m. *
ASOS…………………..17 WNW AT  2:41 P.M.
DAVIS………………….18 WNW AT  3:01 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………..13 WNW AT  4:09 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..13 W   AT 11:51 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….14 NW  AT  5:53 A.M.
AVERAGE WIND SPEED AND DIRECTION………….8.2 NW
ASOS………………….8.5
DAVIS…………………7.2 NW [310 degrees] * last of several occurrences

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……….0.00   DEPARTURE………….-0.16
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE YEAR……….41.92   DEPARTURE………….+2.68
ASOS…………..N/A*
*ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER & OCTOBER 2013 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane wind recording system gust
RMY:  RMY = R.M. Young wind gust recording system added 8/9/2011
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized

9/1  76/67/72/+4/2.32/008/01         33 S   AERO 39 MPH S   RMY 38   TSTM
9/2  79/67/73/+5/0.43/056/07         30 SSE AERO 33 MPH SSE RMY N/A  TSTM
9/3  79/61/70/+3/0.00/219/28         28 S   AERO 29 MPH S   RMY 30   TSTM
9/4  78/57/68/+1/0.00/733/94         24 W   AERO 25 MPH W   RMY 25
9/5  66/51/59/-8/0.08/179/23         20 NNE AERO 20 MPH NNE RMY 21
9/6  68/46/57/-10/0.00/751/97        18 WSW AERO 17 MPH WSW RMY N/A
9/7  78/51/65/-1/0.00/594/77         20 WSW AERO 21 MPH WSW RMY 21
9/8  74/50/62/-4/0.00/646/84         31 NW  AERO 33 MPH NW  RMY 32
9/9  69/47/58/-8/T/536/70            23 SW  AERO 23 MPH SSW RMY N/A
9/10 73/56/65/0/0.03/008/01          30 S   AERO 32 MPH S   RMY 33
9/11 93/68/81/+16/0.00/654/86        25 SW  AERO 27 MPH SW  RMY N/A
9/12 85/66/76/+11/0.47/455/60        32 S   AERO 33 MPH S   RMY 34   TSTM
9/13 79/58/69/+5/0.17/242/32         24 NNW AERO 25 MPH NNW RMY 23
9/14 67/52/60/-4/0.00/361/48         21 NW  AERO 21 MPH NW  RMY 21
9/15 70/48/59/-5/0.00/547/73         17 WSW AERO 18 MPH WSW RMY 20
9/16 66/46/56/-7/0.02/179/24         29 NNW AERO 31 MPH NNW RMY 30
9/17 60/40/50/-13/0.00/722/97        27 NNE AERO 27 MPH NNE RMY 26
9/18 73/47/60/-2/0.00/726/98         18 W   AERO 18 MPH WSW RMY 20
9/19 78/51/65/+3/0.00/731/99         17 WSW AERO 16 MPH WSW RMY 18
9/20 78/54/66/+4/0.00/706/96         18 SSW AERO 18 MPH SSW RMY 23
9/21 74/57/66/+4/T/512/70            35 S   AERO 40 MPH S   RMY N/A
9/22 70/49/60/-1/0.39/365/50         38 S   AERO 39 MPH S   RMY 42
9/23 63/43/53/-7/0.00/711/98         25 NW  AERO 26 MPH NW  RMY 28
9/24 65/40/53/-7/0.00/702/97         22 ENE AERO 22 MPH ENE RMY 23
9/25 64/45/55/-5/0.00/512/71         18 N   AERO 18 MPH N   RMY 19
9/26 63/52/58/-1/0.00/503/70         16 ENE AERO 14 MPH ENE RMY 16
9/27 64/53/59/0/0.00/307/43          21 NE  AERO 20 MPH NE  RMY 20
9/28 70/52/61/+3/0.00/698/98         16 NNE AERO 15 MPH NNE RMY 15
9/29 65/50/58/0/0.00/553/78          15 ESE AERO 15 MPH ESE RMY 15
9/30 64/51/58/0/0.00/…/..          15 NE  AERO 14 MPH ENE RMY N/A

10/1 75/50/63/+6/0.00/…/..         16 WNW AERO 16 MPH WNW RMY 18

10/2 the morning low temp: 56F; the normal low is now 48F

DAILY RECORDS FOR SEPTEMBER 2013
9/1  – NEW DAILY RECORD MAXIMUM PRECIPITATION OF 2.32 INCHES;
surpasses previous record of 1.60 inches set in 1927
9/11 – TIED DAILY RECORD MAXIMUM HIGH TEMPERATURE OF 93F;
ties record of 93F set in 1983

DAILY RECORDS FOR OCTOBER 2013
None so far.

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

RECORDS FOR OCTOBER 2
HIGH 85F IN 1968
LOW 29F IN 1899
PRECIP 1.75 INCHES IN 1984
PEAK GUST 52e MPH S IN 1952, 52 NNW IN 1984

RECORDS FOR OCTOBER 3
HIGH 82F IN 1922
LOW 28F IN 1899
PRECIP 1.76 INCHES IN 1979
PEAK GUST 62 MPH WNW IN 1964

TODAY’S REPORT PREPARED BY: Robert Skilling