Wednesday, September 9, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, SEPTEMBER 9, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

**97F MAXIMUM TEMPERATURE TUESDAY SETS NEW
DAILY RECORD, SURPASSING 93F SET BACK IN 2007**

THE NON-PROFIT BLUE HILL OBSERVATORY LAUNCHES
ONLINE KICKSTARTER FUNDRAISER FOR NEW
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Yesterday afternoon’s 1:00 PM EST observation had already
broken the old daily record of 93F, having reached 94F by
that time. Just after 3:30 PM EST, temperature spike once
again to reach a maximum reading of 97F, now the second
highest record maximum temperature on record in the month
of September. Tuesday also marks the second 90F+ degree
day in a row and the hottest day of the year by 5 degrees.

BHO Highest September Daily Maximum Temperature, deg F (1885-2015)

1) 99 on 2 Sep 1953
2) 97 on 8 Sep 2015
3) 95 on 3 Sep 1929
4) 93 on 23 Sep 1895
93 on 1 Sep 1969
93 on 11 Sep 1983
93 on 8 Sep 2007
93 on 1 Sep 2010
93 on 2 Sep 2010
93 on 11 Sep 2013

The minimum temperature for yesterday of 70F breaks the
record daily minimum temperature for 8 September, surpassing
69F set on that date 1999.

Today’s record of 91F may be in jeopardy as well, set back
in 2002. If we hit the 90F degree mark today, this would mark
only the second official September “heat wave” since 1895, when
on the 21st, 22nd, and 23rd, temperatures hit a maximum of
91, 90 and 93F respectively.

By the 1:00 PM EST observation today, the previous record of
91F was unofficially broken, with a maximum temperature reading
of 92F. Skies were mostly clear, with a few small cumulus in
thin cirrus in all directions. Visibility had improved somewhat
to a hazy 40 miles in all directions.
Today’s Observations:

7 A.M.
Weather: Thin scattered cirrus, few cumulus fractus
distant E-SW
Temperature: 74F; Dew Point: 69F; Wind: SSW at 9 kts,
Sea-level pressure: 29.96 ins. Hg, steady, then rising
Visibility: 20 miles, except 15 miles E-SE,
obscured by light smoke layer in all directions, hazy
6-hr Max temp: 74F
6-hr Min temp: 70F
24-hr precip: 0.00
BHO SA 1155 250 -SCT 20 147/74/69/2109/996/ VSBY E-SE 15 MI
FEW CUFRA DSNT E-SW THN FG ALQDS HAZY/ 8/701 53006 10074 20070

10 A.M.
Weather: Thin broken cirrus, few small cumulus in all directions
Temperature: 85F; Dew Point 67F; Wind: SW at 12G20 kts,
Sea-level pressure: 29.94 ins. Hg, rising, then falling and lower
Visibility: 25 miles, hazy
BHO SA 1455 E250 -BKN 25 139/85/67/2212G20/994/ FEW SML CU ALQDS
HAZY/ 8/101 58008

1 P.M.
Weather: Clear, few small cumulus in all directions, few
thin cirrus fibratus in all directions
Temperature: 90F; Dew Point: 69F; Wind: SSW at 13G22 kts
Sea-level pressure: 29.87 ins. Hg, falling, then more slowly
Visibility: 40 miles, hazy
6-hr Max: 92F
6-hr Min: 74F
BHO SA 155 CLR 40 115/90/69/2013G22/987/ FEW SML CU AND THN CI
ALQDS HAZY/ 8/101 56024 10092 20074
SUMMARY FOR TUESDAY, SEPTEMBER 8, 2015

TEMPERATURE (DEGREES F)
MAX…..97   NORMAL…..74
MIN…..70   NORMAL…..57
MEAN….84   NORMAL…..66

DEPARTURE FROM 30-YEAR NORMAL…………………..+18
TOTAL DEPARTURE FOR THE MONTH…………………..+55  [+6.7 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..19   DEPARTURE………+16
TOTAL COOLING UNITS FOR THE MONTH…………..71   DEPARTURE………+44
TOTAL COOLING UNITS FOR THE SEASON…………737   DEPARTURE……..+173
TOTAL COOLING UNITS LAST SEASON TO DATE…….561   DIFFERENCE…….+176

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….22 WSW AT  2:02 P.M.
ASOS……………………23  SW AT  2:43 P.M.
DAVIS…………………..21 WSW AT  2:01 P.M. RMY 24
FASTEST MILE FOR YESTERDAY…………………15  SW AT 12:14 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………16  SW AT 12:14 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..14  SW AT  N/A
AVERAGE WIND SPEED AND DIRECTION…………..9.5 WSW
ASOS…………………..9.8
DAVIS………………….8.6 WSW [252 DEG]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…..0.00  DEPARTURE…..-0.12
ASOS……………0.00
TOTAL PRECIPITATION FOR THE MONTH……….Trace  DEPARTURE…..-0.96
ASOS……………0.00
TOTAL PRECIPITATION FOR THE YEAR………..30.26  DEPARTURE…..-5.72
ASOS…………….N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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

9/1  81/65/73/+5/0.00/…/..               20 SSW RMY 20
9/2  89/64/77/+9/0.00/…/..               20 SW  RMY 21
9/3  85/66/76/+9/T/…/..                  17 E   RMY N/A TSTM
9/4  72/58/65/0/0.00/…/..                31 ENE RMY N/A
9/5  77/55/66/-1/0.00/…/..               14 SW  RMY 18
9/6  87/57/72/+5/0.00/…/..               21 SSW RMY 22
9/7  92/63/78/+12/0.00/…/..              23 WSW RMY 24
9/8  97/70/84/+18/0.00/…/..              22 WSW RMY 24

9/9  low since midnight is 70F; normal low is now 57F

DAILY RECORDS FOR SEPTEMBER 2015

**9/7 DAILY RECORD MAXIMUM TEMPERATURE OF 92F
TIES PREVIOUS RECORD SET IN 2007**
**9/8 DAILY RECORD MAXIMUM TEMPERATURE OF 97F
BREAKS PREVIOUS RECORD of 93F SET IN 2007**
**9/8 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 70F
BREAKS PREVIOUS RECORD of 69F SET IN 1999**
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):

RECORDS FOR SEPTEMBER 9
HIGH 91F IN 2002
LOW 41F IN 1938
PRECIP 1.97 INCHES IN 1969
PEAK GUST 52 MPH WNW IN 1969, NW IN 1978

RECORDS FOR SEPTEMBER 10
HIGH 90F IN 1931,1989
LOW 41F IN 1956
PRECIP 5.60 INCHES IN 1999 (DAILY RECORD FOR SEPTEMBER)
PEAK GUST 48 MPH NW IN 1972

TODAY’S REPORT PREPARED BY: Brian Fitzgerald