Thursday, September 5, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, SEPTEMBER 5, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

Cooler and cloudy with an A.M. shower

This morning was overcast with showers to the northwest. The showers are
a leading edge of cooler air. Temperatures  throughout the afternoon
have been cool, hovering in the low 60s.The showers moved in earlier this morning
around 8-9am. The shower was quick and ended between 9-10am.The total precipitation
is .08 inch.. A brisk north/northeast cool wind  developed this afternoon.
creating a fall like feel. Most of day has continue to be overcast with a few quick
breaks. Also, lots of cumulus clouds with dark bottoms indicating the
possibility of more showers.

The visibility has been improving throughout the day. This morning at 7am it
was about 30 miles. We have improved to 75 miles in just a couple of hours. Along
with the clearing visibility our temperatures have been dropping. It appears
that with drier air and north wind, we could have our first cold morning tomorrow!

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: Overcast altocumulus (2 levels), opacqus, duplicatus,
bright spots in overcast northeast thru southeast, showers of
rain 25 miles west thru north moving east
Temperature: 63F; Dew Point: 57F; Wind: W at 8 kts.
Sea-level pressure: 29.92 ins. Hg, rising, then rising more rapidly
Visibility: 30 miles, 25 SW-NW, 40 NE
6-hr min. temp: 62F
BHO SA 1155 E75 BKN 85 OVC 30 131/63/57/2708/992/ BRGHT SPTS
IOVC NE-SE SHRA 25 W-N MOVG E VSBY W-N 25 NE 40 LGT HZ/ 8/07/
53012 10065 20062

10 A.M.
Weather:Scattered stratocumulus, broken altocumulus (chaotic),
Overcast dense cirrus, break in overcast SE-SW and line clearing,
distance W-NW. Sun dimly visible.
Temperature: 64F Dew Point: 61F; Wind N at 8 kts
Sea-level pressure: 29.96 ins. Hg, rising, then rising more slowly
Visibility: 45 miles, distance haze
3 hour precip: 0.08 inch
BHO SA 1455 65 SCT E90 BKN 200 OVC 45 145/64/61/3508/996/ SC/MDT CUFRM
TOPS DSNT ALQDS AC CHAOTIC OVC DNS CI BINOVC SE-SW AND BINOVC/LINE OF
CLRG DSNT NW SUN DMLY VSB DSNT HZ/ 8/592 51014 MANUAL 6008/ ASOS 60007

1 P.M.
Weather: Scattered stratocumulus, moderate cumuloform tops and dark
bases, broken altocumulus chaotic, overcast dense cirrus and cirrus,
small breaks in overcast, break in overcast/line of clearing distant W-N
Temperature: 64F; Dew point: 57F; Wind: NE at 8 knts
Sea-level pressure: 29.99 ins. Hg, rising, then rising more slowly
Visibility: 75 miles, distant light haze
6-hr max. temp: 66F
6-hr precip: 0.08 inch
BHO SA 1755 E32 BKN 40 BKN 130 BKN 200 OVC 75 155/64/57/0508/999/
SC/MDT CUFRM TOPS/DRK BASES SML BINOVC BINOVC/LINE OF CLRG DSNT
W-N AC CHAOTIC/DNS CI ALQDS LGT DSNT HZ/ 8/592 51010 ASOS 60007
MANUAL 6008/ 10066 20061

WEATHER SUMMARY FOR WEDNESDAY, SEPTEMBER 4, 2013

TEMPERATURE (DEGREES F)
MAX…..78     NORMAL…..76
MIN…..57     NORMAL…..59
MEAN….68     NORMAL…..67

DEPARTURE FROM 30-YEAR NORMAL…………………..+1
TOTAL DEPARTURE FOR THE MONTH………………….+13 [+3.1 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..3   DEPARTURE………-1
TOTAL COOLING UNITS FOR THE MONTH………….23   DEPARTURE………+8
TOTAL COOLING UNITS FOR THE SEASON………..663   DEPARTURE…….+111
TOTAL COOLING UNITS LAST SEASON TO DATE……724   DIFFERENCE…….-61

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY…………….24 W   AT  4:54 P.M
AERO…………………25 W   AT  4:50 P.M
ASOS…………………25 W   AT  4:55 P.M
DAVIS………………..25 WSW AT  4:01 P.M  RMY 25
FASTEST MILE FOR YESTERDAY………………19 W   AT  4:46 P.M
MAXIMUM 2-MINUTE ASOS AVERAGE……………20 W   AT  4:55 P.M
MAXIMUM 2-MINUTE DAVIS AVERAGE…………..17 WSW AT  2:01 P.M
AVERAGE WIND SPEED AND DIRECTION…………11.8 W
ASOS…………………11.5 W
DAVIS………………..10.3 W [270 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……….2.75   DEPARTURE………….+2.29
ASOS…………..2.88
TOTAL PRECIPITATION FOR THE YEAR……….40.76   DEPARTURE………….+5.28
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  79/61/70/+3/0.00/…/..         28 S   AERO 29 MPH S   RMY 30
9/4  78/57/68/+1/0.00/…/..         24 W   AERO 25 MPH W   RMY 25

9/5  morning low temp: 62F; the normal low is now 58F

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 5
HIGH 90F IN 1971
LOW 45F IN 1906
PRECIP 1.37 INCHES IN 1907
PEAK GUST 46 MPH NW IN 1994

RECORDS FOR SEPTEMBER 6
HIGH 92F IN 1900
LOW 39F IN 1888
PRECIP 3.19 INCHES IN 1890
PEAK GUST 78e MPH SE IN 1979 (TROPICAL STORM DAVID)

TODAY’S REPORT PREPARED BY: ROBERT SKILLING AND KEVIN PECORA