Friday, August 2, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, AUGUST 2, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

LIGHT RAIN SHOWERS BRING 0.24 INCH OF RAIN OVERNIGHT;
FOGGY TO START, BUT CLEARING, DRYING, AND WARMING NICELY THIS AFTERNOON

Intermittent light rain showers that began yesterday evening became
briefly moderate overnight before ending shortly after 9 A.M. EDT. The
total rainfall on the summit reached 0.24 inch.

The summit began the day shrouded in fog, with visibility reduced to 1/16th
of a mile (picture can be found under Member Content at bluehill.org). A
cold front passed through shortly after 8 A.M. EDT, and conditions gradually
improved from there. Only scattered cumulus remain this afternoon, and with
a drying air mass, visibility has reached 65 miles to the NW. The dew point
temperature is dropping into the lower 60s as the temperature warms up
nicely near 80F.

For July 2013, the average monthly maximum temperature of 83.2F was the
13th warmest on record, but the average monthly minimum temperature of
66.9F was the WARMEST on record for July and for any month of the year.
This broke the previous record of 65.9F in 2010 by an entire degree F.

Additional July statistics can be found below.

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

TEMPERATURE:
Average Max Temp: 83.2F [+2.4F] Average Min Temp: 66.9F [+4.0F] Mean Temp: 75.1F [+3.2F] 24-hr. Corr. Mean Temp: 74.1F [+3.3F] Max Temp: 95F on 19th
Min Temp: 57F on 25th

Total heating degree day units (month): 6 [-3] *NCDC method
Total heating degree day units (season): 6 [-3] *start July 1 (NCDC)
Total cooling degree day units (month): 327 [+105] *NCDC method
Total cooling degree day units (season): 483 [+132] *start Jan 1 (NCDC)

PRECIPITATION:
Total precipitation: 3.09 inches [-0.93 inch] Greatest 24-hr precipitation: 1.03 on 25th/26th

WIND:
Avg wind speed: 9.5 MPH
Avg corrected wind speed: 10.1 MPH
Prevailing wind direction: SW [12%] Peak gust: 38 MPH SSW on 7th
Peak fastest mile: 32 MPH SSW on 7th

SUNSHINE:
Astronomical minutes: 14,428 of a possible 27,729 or 52%

BHO Warmest July’s, deg F (1885-2013)
1) 75.1 in 2010
2) 74.9 in 1952
3) 74.1 in 1994
74.1 in 2013
5) 74.0 in 2011
6) 73.8 in 1999
7) 73.5 in 1949
8) 73.2 in 2012

BHO Warmest July Average Minimum Temperature, deg F (1885-2013)
1) 66.9 in 2013
2) 65.9 in 2010
3) 65.6 in 1994
4) 65.3 in 2006
5) 65.1 in 2008

BHO Greatest Number of 90-Degree Days per Month, (1885-2013)
1) 14 in July 1952
2) 13 in August 2002
3) 10 in August 1944
10 in July 1949
10 in July 1963
10 in July 2010
10 in July 2013
8) 9 in July 1911
9 in August 1928
10) 8 in August 1949
8 in July 1963
8 in July 1988

BHO July Greatest CDD Total, deg F (1885-2013)
1) 355 in 2010
2) 342 in 1952
3) 329 in 1994
4) 327 in 2013
5) 313 in 1949
6) 308 in 1999
7) 303 in 1911

Today’s Observations:

7 A.M.
Weather: Sky obscured by dense fog, stratus drifting over summit, light
rain shower briefly moderate from 6:05-6:10 A.M. EST, becoming very light
at 6:25 A.M. EST, becoming light drizzle at unknown time and ended at
unknown time
Temperature: 65F; Dew Point: 65F; Wind: Estimated SSW at 2 kts,
Wind: Light and variable
Sea-level pressure: 29.84 ins. Hg, rising
Visibility: 1/2 mile, dense fog
24-hr precip: 0.22 inch
6-hr precip: 0.21 inch
6-hr min. temp: 62F
BHO SA 1155 W4 X 1/2F 106/65/65/E2102/984/ STRA DRFTNG OVR SMT WND LGT
AND VRB RW- BRFLY RW 05-10 RW- BCMG VRY LGT 25 BCMG L-UKN EUKN/ 8////
53007 ASOS 70021 MANUAL 70022 ASOS 60021 MANUAL 60021 10065 20062

10 A.M.
Weather: Broken cumulus, broken stratus fractus, broken cirrus, few
moderate cumulus all quadrants, distant haze
Temperature: 71F; Dew Point: 67F; Wind: WNW at 7 kts.
Sea-level pressure: 29.85 ins. Hg, rising slightly
Visibility: 40 miles, NE-SE 30 miles, S-NNW 50 miles, distant haze
3-hr precip: 0.02 inch
BHO SA 1455 E10 BKN 15 BKN 250 BKN 40 107/71/67/2907/985/ FEW MDT CU
ALQDS DSNT HZ VSBY NE-SE 30 S-NNW 50/ 8/801 51001 ASOS 60002 MANUAL 60002

1 P.M.
Weather: Scattered cumulus, scattered cirrostratus, scattered thin cirrus,
moderate cumulus all quadrants, cirrus/cirrostratus distant NE-SE, light
distant haze
Temperature: 80F; Dew Point: 64F; Wind: W at 9 kts,
Wind: Direction variable WSW-WNW
Sea-level pressure: 29.84 ins. Hg, falling slightly
Visibility: 60 miles, NE-SE 50 miles, NW 65 miles, light distant haze
6-hr precip: 0.02 inch
6-hr max. temp: 80F
BHO SA 1755 25 SCT 200 SCT 250 –SCT 60 104/80/64/2709/984/ MDT CU ALQDS
CI/CS DSNT NE-SE LGT DSNT HZ VSBY NE-SE 50 NW 65 WND 24V30/ 8/208 58003
ASOS 60002 MANUAL 60002 10080 20064

WEATHER SUMMARY FOR THURSDAY, AUGUST 1, 2013

TEMPERATURE (DEGREES F)
MAX…..81 NORMAL…..81
MIN…..62 NORMAL…..63
MEAN….72 NORMAL…..72

DEPARTURE FROM 30-YEAR NORMAL……………….0
TOTAL DEPARTURE FOR THE MONTH……………….0 [0.0 DEGREE/DAY]

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY…………….25 S AT 3:54 P.M.
AERO…………………26 S AT 3:54 P.M.
ASOS…………………26 S AT 9:42 P.M.
DAVIS………………..26 S AT 3:14 P.M. RMY 27
FASTEST MILE FOR YESTERDAY………………20 S AT 3:15 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………21 SSW AT 3:17 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………..20 S AT 3:16 P.M.
AVERAGE WIND SPEED AND DIRECTION……….10.0 S
ASOS………………..9.9
DAVIS……………….9.0 S [189 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.22 DEPARTURE…………+0.07
ASOS…………..0.21
TOTAL PRECIPITATION FOR THE MONTH……….0.22 DEPARTURE…………+0.07
ASOS…………..0.21
TOTAL PRECIPITATION FOR THE YEAR……….35.51 DEPARTURE…………+4.37
ASOS…………..N/A*
*ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals

PRELIMINARY CLIMATE SUMMARY FOR JULY & AUGUST 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

7/1 82/69/76/+6/0.05/247/27 29 S AERO 31 MPH SSW RMY 32
7/2 82/61/72/+2/T/100/11 23 SSW AERO 23 MPH SSW RMY 25
7/3 87/62/75/+4/T/556/61 28 SW AERO 30 MPH SW RMY 30
7/4 90/71/81/+10/0.00/811/89 25 WSW AERO 26 MPH SW RMY 28
7/5 92/73/83/+12/0.00/874/96 24 W AERO 25 MPH WSW RMY 25
7/6 90/73/82/+11/0.00/836/92 25 WNW AERO 25 MPH WNW RMY 26
7/7 91/72/82/+11/0.21/508/56 38 SSW AERO 43 MPH SSW RMY 44 TSTM
7/8 82/64/73/+1/0.04/617/68 18 NE AERO 20 MPH NE RMY 20 TSTM
7/9 72/63/68/-4/0.01/054/06 14 ENE AERO 14 MPH ENE RMY 14
7/10 84/65/75/+3/T/335/37 32 S AERO 36 MPH S RMY 35
7/11 79/69/74/+2/0.62/009/01 23 W AERO 23 MPH W RMY N/A TSTM
7/12 70/62/66/-6/0.00/162/18 29 NE AERO 29 MPH NE RMY 30
7/13 75/62/69/-3/0.08/009/01 21 ENE AERO 20 MPH ENE RMY N/A
7/14 89/71/80/+8/0.00/477/53 16 W AERO 16 MPH W RMY 16
7/15 91/72/82/+10/0.00/665/74 17 NW AERO 16 MPH NW RMY 18
7/16 91/71/81/+9/0.00/843/94 18 NNW AERO 16 MPH NNW RMY 16
7/17 93/74/84/+12/0.00/841/94 22 SW AERO 23 MPH SW RMY 25
7/18 90/75/83/+11/0.00/724/81 20 S AERO 21 MPH S RMY 22
7/19 95/76/86/+14/0.00/723/81 36 WSW AERO 38 MPH WSW RMY 38
7/20 93/72/83/+11/0.00/570/64 29 W AERO 30 MPH W RMY 31 TSTM
7/21 82/68/75/+3/0.00/568/64 16 NE AERO 16 MPH NE RMY 17
7/22 80/67/74/+2/T/514/58 17 NE AERO 17 MPH NE RMY 19 TSTM
7/23 82/68/75/+3/0.82/159/18 35 WSW AERO 36 MPH WSW RMY 39
7/24 84/64/74/+2/0.00/627/71 23 N AERO 23 MPH N RMY 23
7/25 64/57/61/-11/0.43/000/00 24 NNE AERO 24 MPH NNE RMY 25
7/26 67/59/63/-9/0.70/000/00 23 NNW AERO 23 MPH N RMY 23
7/27 82/60/71/-1/0.00/535/61 22 S AERO 23 MPH S RMY 23
7/28 78/66/72/0/0.03/149/17 16 ENE AERO 16 MPH ENE RMY 15
7/29 81/66/74/+2/0.10/402/46 20 S AERO 18 MPH S RMY 21 TSTM
7/30 81/61/71/-1/0.00/766/88 20 WNW AERO 18 MPH WNW RMY 20
7/31 80/61/71/-1/0.00/747/86 16 S AERO 15 MPH S RMY 16

8/1 81/62/72/0/0.01/…/.. 25 S AERO 26 MPH S RMY 27

8/2 morning low temp: 62F; the normal low is now 63F

DAILY RECORDS FOR JULY 2013
7/14 – TIED DAILY RECORD HIGH MINIMUM TEMPERATURE OF 71F;
ties previous record of 71F set in 1997
7/15 – NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 72F;
surpasses previous record of 70F set in 1901, 1934, 1995
7/16 – TIED DAILY RECORD HIGH MINIMUM TEMPERATURE OF 71F;
ties previous record of 71F set in 1901, 1958, 1968
7/17 – TIED DAILY RECORD HIGH MINIMUM TEMPERATURE OF 74F;
ties previous record of 74F set in 1900
7/18 – NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 75F;
surpasses previous record of 73F set in 1900, 1999
7/19 – NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 76F;
surpasses previous record of 72F set in 1949, 1991, 2005

DAILY RECORDS FOR AUGUST 2013
None so far.

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

RECORDS FOR AUGUST 2
HIGH 101F IN 1975 [STATION RECORD MAXIMUM – Tied with 8/10/1949] LOW 50 IN 1929, 1947
PRECIP 1.59 INCHES IN 1946
PEAK GUST 50 MPH SW IN 2006

RECORDS FOR AUGUST 3
HIGH 96F IN 1930
LOW 50F IN 1976
PRECIP 1.45 INCHES IN 1979
PEAK GUST 52 MPH NW IN 2008 [TSTM]

TODAY’S REPORT PREPARED BY: Sean Fankhauser