Sunday, September 1, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, SEPTEMBER 1, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

IN LIKE A LION:
THUNDERSTORMS BRING HEAVY BOUTS OF RAIN AND WIND TO THE SUMMIT ON THE
FIRST DAY OF SEPTEMBER

September got started with a bang as the summit was hit with heavy rain,
wind gusts into the 30+ MPH range, and occasional (and at times frequent)
cloud to cloud, inter-cloud, and cloud to ground lightning strikes.

The preliminary precipitation total is 2.30 inches in just over 6 hours,
with the heaviest rain falling at a rate of nearly 0.12 inch per minute!
Peak gust during the day occurred nearly simultaneously with the heaviest
downpours, reaching 33 MPH out of the south. Flash flood warnings were
also issued in the area.

Today’s Observations:

7 A.M.
Weather: Broken cumulus/stratocumulus, overcast stratocumulus, cumulonimbus
distant SSE-WSW, light fog
Temperature: 70F; Dew Point: 69F; Wind: S at 10 kts,
Sea-level pressure: 29.90 ins. Hg, increasing then steady
Visibility: 10 miles, light fog
Manual 24-hr precip: 0.04 inch
ASOS 24-hr precip: 0.02 inch
6-hr min. temp: 69F
BHO SA 1155 80 BKN 120 OVC 10-R 124/70/69/1810/990/ DSNT CB SSE-WSW
VSBY 15 NE 5 NW AND ENE LT F ALQDS/ 8/31/ 51018 MANUAL 70004 ASOS 70002
10070 20069

10 A.M.
Weather: Scattered cumulus fractus/cumulus/cumulonimbus,
overcast stratocumulus/cumulonimbus, continuing thunderstorms and
rain (began 7:10 A.M. EST), storm moving from west to east
Temperature: 68F; Dew Point: 68F; Wind: SW at 12 kts,
Wind: Peak Gust: S 33 MPH at 8:57 A.M. EST
Sea-level pressure: 29.90 ins. Hg, increasing then decreasing
Visibility: 10 miles, steady moderate rain
3 Hour Manual Precip: 2.04 inches
3 Hour ASOS Precip: 2.13 inches
BHO SA 1455 30 SCT 60 SCT E80 OVC 10TSRA 126/68/68/2212/990/ TSRA CONTD
OCNL LTGCCCICG TS SW MOVG E PEAK GUST 2233/1357/ 8/37/ 50002
MANUAL 60204 ASOS 60213

1 P.M.
Weather: Scattered cumulus, overcast stratocumulus, cumulonimbus with
showers in the vicinity to the SSE-WSW moving E, few breaks in overcast
Temperature: 74F; Dew Point: 73F; Wind: SSW at 8 kts,
Sea-level pressure: 29.89 ins. Hg, steady then decreasing
Visibility: 10 miles, thin fog all quads
Visibility: 5 miles SSE-WSW and NW-NNE
6-hr max. temp: 74F
6 Hour Manual Precip: 2.28 inches
6 Hour ASOS Precip: 2.42 inches
BHO SA 1755 5 SCT 30 OVC 10 123/74/73/2108/989/ TSE1650 MOVD E
CB W MOVG E W/SHRA VC SSE-WSW FEW BINOVC VSBY 5 SSE-WSW AND NW-NNE
THN F ALQDS/ 8/3// 58003 MANUAL 60228 ASOS 60242 10074 20070

WEATHER SUMMARY FOR SATURDAY, AUGUST 31, 2013

TEMPERATURE (DEGREES F)
MAX…..81     NORMAL…..77
MIN…..67     NORMAL…..60
MEAN….72     NORMAL…..68

DEPARTURE FROM 30-YEAR NORMAL…………………..+4
TOTAL DEPARTURE FOR THE MONTH………………….-26  [-0.8 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..7   DEPARTURE………+4
TOTAL COOLING UNITS FOR THE MONTH…………154   DEPARTURE……..-32
TOTAL COOLING UNITS FOR THE SEASON………..637   DEPARTURE……..+100
TOTAL COOLING UNITS LAST SEASON TO DATE……712   DIFFERENCE…….-75

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY…………….21 SSW AT  10:06 P.M. *
AERO…………………22 S   AT  9:42  P.M.
ASOS…………………23 S   AT  9:38  P.M.
DAVIS………………..22 S   AT  9:42  P.M. RMY 23
FASTEST MILE FOR YESTERDAY………………17 SSW AT  10:15 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………17 SSW AT  11:46 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………..17 SSW AT  10:41 P.M.
AVERAGE WIND SPEED AND DIRECTION……….11.5 SSW
ASOS……………….11.1
DAVIS………………10.8 SSW [205 deg.] * last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.05   DEPARTURE………….-0.06
ASOS…………..0.04
TOTAL PRECIPITATION FOR THE MONTH……….2.72   DEPARTURE………….-1.31
ASOS…………..2.75
TOTAL PRECIPITATION FOR THE YEAR……….38.01   DEPARTURE………….+2.99
ASOS…………..N/A*
*ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals

PRELIMINARY CLIMATE SUMMARY FOR 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

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  79/58/69/-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/-1/0.00/795/94         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 80/62/71/0/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
8/23 78/63/70/0/0.00/610/75          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 81/62/73/+3/T/…/..            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/+2/0.05/000/00         17 WSW AERO 18 MPH WSW RMY 21
8/31 81/67/72/+4/0.02/000/00         21 SSW AERO 22 MPH S   RMY 23

9/1  morning low temp: 69F; the normal low is now 60F

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 SEPTEMBER 1
HIGH 93F IN 1969, 2010
LOW 47F IN 1975
PRECIP 1.60 INCHES IN 1927
PEAK GUST 59e MPH S IN 1945, SSW IN 1965

RECORDS FOR SEPTEMBER 2
HIGH 99F IN 1953 (SEPTEMBER MAXIMUM RECORD)
LOW 44F IN 1909
PRECIP 2.73 INCHES IN 1947
PEAK GUST 55e MPH WNW IN 1944

TODAY’S REPORT PREPARED BY: Forrest Iwanik