Tuesday, September 3, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, SEPTEMBER 3, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

MOSTLY CLOUDY, WARM AND HUMID

Another 0.07 inch of rain fell with and additional shower yesterday
afternoon, bringing the Sept 1-2 rainfall total up to 2.75 inches. Sunday’s
rainfall set a new daily record of 2.32 inches for the date, surpassing
the previous record of 1.60 inches in 1927.

Today, it continues to be warm and humid. Temperatures are averaging about
5-10 degrees above normal. Dew point temperatures continue to hang in the
mid and upper 60s. A persistent, although light, SW flow continues.

Rain and thunderstorms have remained to our south and west today, with no
precipitation occurring on the summit through 5 P.M. EDT. A few distant
rumbles of thunder have been heard.

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

TEMPERATURE:
Average Max Temp: 78.5F [-0.7F] Average Min Temp: 60.7F [-1.1F] Mean Temp: 69.6F [-0.9F] 24-hr. Corr. Mean Temp: 68.8F [-0.6F] Max Temp: 87F on 21st
Min Temp: 53F on 15th

Total heating degree day units (month): 6 [-10] *NCDC method
Total heating degree day units (season): 12 [-13] *start July 1 (NCDC)
Total cooling degree day units (month): 157 [-29] *NCDC method
Total cooling degree day units (season): 640 [+103] *start Jan 1 (NCDC)

PRECIPITATION:
Total precipitation: 2.72 inches [-1.31 inches] Greatest 24-hr precipitation: 2.21 on 9th

WIND:
Avg wind speed: 9.8 MPH
Avg corrected wind speed: 10.3 MPH
Prevailing wind direction: W [16%] Peak gust: 37 MPH S on 9th
Peak fastest mile: 28 MPH SSW on 9th

SUNSHINE:
Astronomical minutes: 16,623 of a possible 25,727 or 65%
Campbell-Stokes sun card minutes: 16,086 of a possible 24,780 or 65%

METEOROLOGICAL SUMMER 2013 (JUNE, JULY, AUGUST) PRELIMINARY STATISTICS:
(departures relative to 1981-2010 average)

TEMPERATURE:
Average Max Temp: 79.4F [+1.1F] Average Min Temp: 61.9F [+1.3F] Mean Temp: 70.7F [+1.2F] 24-hr. Corr. Mean Temp: 69.8F [+1.3F] Max Temp: 95F on July 19th
Min Temp: 48F on June 4th

PRECIPITATION:
Total precipitation: 17.92 inches [+5.56 inches]

Blue Hill Warmest Summers (Jun-Aug), deg F:
1) 71.3 in 2010
2) 70.8 in 1949
3) 70.6 in 1999
4) 70.4 in 1952
5) 70.2 in 2005
6) 70.1 in 1994
7) 70.0 in 1973
70.0 in 2012
9) 69.9 in 1988
10) 69.8 in 2013

Blue Hill Warmest Jan-Aug, deg F:
1) 53.5 in 2012
2) 53.0 in 2010
3) 52.0 in 1991
4) 51.9 in 1949
51.9 in 1998
51.9 in 2002
7) 51.7 in 1999
8) 51.1 in 2006
9) 51.0 in 1973
51.0 in 2013

Blue Hill Wettest Summers (Jun-Aug), inches:
1) 25.22 in 1998
2) 24.61 in 1955
3) 24.09 in 1938
4) 21.56 in 2006
5) 21.02 in 1922
6) 20.23 in 1982
7) 18.71 in 1989
8) 17.92 in 2013
9) 17.42 in 1927
10) 17.20 in 1921

Today’s Observations:

7 A.M.
Weather: Scattered cumulus/stratus fractus, scattered dense cirrus,
scattered thin cirrus, small cumulus/stratus fractus E-WSW and distant
NW-NE, low stratus/haze layer below inverstion distant SSE-NW-NE, inversion
top estimated at 1,000 feet over the city to the N, dense cirrus patches
distant SSW, hazy
Temperature: 70F; Dew Point: 68F; Wind: WSW at 7 kts.
Sea-level pressure: 29.79 ins. Hg, rising
Visibility: 10 miles, hazy
24-hr precip: 0.15 inch
6-hr min. temp: 68F
BHO SA 1155 4 SCT 220 SCT 250 –SCT 10 087/70/68/2407/979/ SML CU/STRFA
E-WSW AND DSNT NW-NE LW STRA/HZ LYR BLO INVSN DSNT SSE-NW-NE INVSN TOP
ESTMTD 1000 FT OVR CTY N DNS CI PTCHS DSNT SSW HAZY/ 8/602 51024
MANUAL 70015 ASOS 70018 10070 20068

10 A.M.
Weather: Scattered altocumulus (2 levels), broken altostratus, broken
cirrostratus, broken cirrus, few small cumulus NNE-E and ESE-SSW and distant
WNW-NNW, few altocumulus castellanus NW, sun dimly visible, distant haze
Temperature: 77F; Dew Point: 65F; Wind: SW at 6 kts,
Wind: Direction variable SSW-W
Sea-level pressure: 29.79 ins. Hg, rising slightly
Visibility: 30 miles, distant haze
BHO SA 1455 100 SCT 160 SCT E180 BKN 200 BKN 250 BKN 30 089/77/65/2306/979/
FEW SML CU NNE-E AND ESE-SSW AND DSNT WNW-NNW FEW ACC NW SUN DIMLY VSBL
DSNT HZ WND 21V27/ 8/187 50002

1 P.M.
Weather: Scattered stratocumulus (2 levels) overcast altostratus, few
mammatus in the vicinity of the station and overhead, distant haze
Temperature: 75F; Dew Point: 68F; Wind: SW at 7 kts.
Sea-level pressure: 29.77 ins. Hg, falling
Visibility: 30 miles, distant haze
6-hr max. temp: 79F
BHO SA 1755 25 SCT 50 SCT E120 OVC 30 081/75/68/2207/977/ FEW MAMMA
VCTY/OVHD DSNT HZ/ 8/57/ 56008 70079 20070

WEATHER SUMMARY FOR MONDAY, SEPTEMBER 2, 2013

TEMPERATURE (DEGREES F)
MAX…..79 NORMAL…..76
MIN…..67 NORMAL…..59
MEAN….73 NORMAL…..68

DEPARTURE FROM 30-YEAR NORMAL…………………..+5
TOTAL DEPARTURE FOR THE MONTH…………………..+9 [+4.3 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..8 DEPARTURE………+4
TOTAL COOLING UNITS FOR THE MONTH………….15 DEPARTURE………+7
TOTAL COOLING UNITS FOR THE SEASON………..654 DEPARTURE…….+109
TOTAL COOLING UNITS LAST SEASON TO DATE……720 DIFFERENCE…….-66

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY…………….30 SSE AT 5:49 A.M.
AERO…………………33 SSE AT 5:49 A.M.
ASOS…………………32 SSE AT 5:50 A.M.
DAVIS………………..32 SSE AT 5:49 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………25 SSE AT 5:49 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………23 SSE AT 5:50 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………..22 SSE AT 5:48 A.M.
AVERAGE WIND SPEED AND DIRECTION……….11.1 S
ASOS……………….10.6
DAVIS………………10.0 S [181 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.15 DEPARTURE………….+0.04
ASOS…………..0.18
TOTAL PRECIPITATION FOR THE MONTH……….2.75 DEPARTURE………….+2.53
ASOS…………..2.88
TOTAL PRECIPITATION FOR THE YEAR……….40.76 DEPARTURE………….+5.52
ASOS…………..N/A*
*ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals

PRELIMINARY CLIMATE SUMMARY FOR AUGUST & SEPTEMBER 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

8/1 81/62/72/0/0.01/503/58 25 S AERO 26 MPH S RMY 27
8/2 81/62/72/0/0.23/518/60 26 W AERO 26 MPH W RMY 28
8/3 77/63/70/-2/T/276/32 22 WSW AERO 23 MPH WSW RMY 23
8/4 79/59/69/-3/T/645/75 25 WNW AERO 21 MPH WNW RMY 26
8/5 75/54/65/-7/0.00/858/100 26 WNW AERO 25 MPH WNW RMY 27
8/6 78/56/67/-5/0.00/846/99 17 ESE AERO 15 MPH S RMY 16
8/7 80/59/70/-2/0.00/759/89 21 S AERO 21 MPH S RMY N/A
8/8 79/62/71/-1/0.08/153/18 25 S AERO 25 MPH S RMY N/A
8/9 73/70/72/0/2.21/000/00 37 S AERO 39 MPH S RMY 40
8/10 81/61/71/0/0.00/795/94 30 WNW AERO 31 MPH WNW RMY 31
8/11 78/58/68/-3/0.00/835/99 18 W AERO 18 MPH W RMY 21
8/12 81/62/72/+1/0.00/656/78 18 W AERO 17 MPH WSW RMY 19
8/13 73/64/69/-2/0.02/193/23 16 SSE AERO 15 MPH SSE RMY N/A
8/14 73/57/65/-6/0.00/819/98 35 W AERO 35 MPH W RMY 35
8/15 75/53/64/-7/0.00/800/96 23 W AERO 23 MPH W RMY 24
8/16 77/57/67/-4/0.00/740/89 20 W AERO 19 MPH W RMY 21
8/17 77/59/68/-3/0.00/770/93 18 W AERO 18 MPH W RMY N/A
8/18 80/61/71/0/T/231/28 16 SSW AERO 17 MPH SSW RMY 18
8/19 82/58/70/0/T/494/60 17 W AERO 18 MPH W RMY 20
8/20 85/64/75/+5/0.00/772/94 17 NW AERO 18 MPH NW RMY N/A
8/21 87/65/76/+6/0.00/802/98 18 WSW AERO 18 MPH WSW RMY 18
8/22 84/67/76/+6/0.00/432/53 22 SW AERO 22 MPH SSW RMY N/A TSTM
8/23 78/63/71/+1/0.00/610/75 25 NNW AERO 25 MPH NNW RMY 24
8/24 73/55/64/-6/0.00/786/97 23 NNE AERO 22 MPH NNE RMY N/A
8/25 82/57/70/+1/0.00/791/98 20 SW AERO 21 MPH SW RMY 21
8/26 80/64/72/+3/T/145/18 26 WSW AERO 26 MPH SW RMY 28
8/27 78/66/72/+3/0.07/329/41 16 NE AERO 15 MPH NE RMY 16
8/28 81/62/72/+3/T/631/79 26 NE AERO 24 MPH NE RMY 27
8/29 64/58/61/-8/0.05/000/00 23 NNE AERO 23 MPH NNE RMY 23
8/30 81/58/70/+2/0.00/429/54 17 WSW AERO 18 MPH WSW RMY 21
8/31 81/67/74/+6/0.05/005/01 21 SSW AERO 22 MPH S RMY 23

9/1 76/67/72/+4/2.32/…/.. 33 S AERO 39 MPH S RMY 38 TSTM
9/2 79/67/73/+5/0.43/…/.. 30 SSE AERO 33 MPH SSE RMY N/A TSTM

9/3 morning low temp: 68F; the normal low is now 59F

DAILY RECORDS FOR AUGUST 2013
None.

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

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

RECORDS FOR SEPTEMBER 3
HIGH 95F IN 1929
LOW 43F IN 1983
PRECIP 3.82 INCHES IN 1972 (TROPICAL STORM CARRIE)
PEAK GUST 58 MPH NNE IN 1972 (TROPICAL STORM CARRIE)

RECORDS FOR SEPTEMBER 4
HIGH 90F IN 1953, 1973
LOW 46F IN 1987
PRECIP 3.22 INCHES IN 1922
PEAK GUST 47 MPH SE IN 1966

TODAY’S REPORT PREPARED BY: Sean Fankhauser