Friday, September 1, 2017

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, SEPTEMBER 1, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME

COOL AND DRY FIRST DAY OF SEPTEMBER

Temperatures remained cool and below seasonable throughout the day
with a high of 67F by 1:00 PM EST. The normal for September first is 76F.
We also had a potential record tying overnight low of 47F. This record
was originally set in 1975. The cool air was also dry with humidity
dropping from 59% at 7:00 AM EST down to 32% by 1:00 PM EST. This made
for excellent visibility of 80 miles during all the physical observations.
Winds were consistent and moderate from the west/north west. Skies were
clear for most of the day with a mixture of cirrus and cumulus clouds.

PRELIMINARY STATS FOR AUGUST 2017

TEMPERATURE, Deg. F
Avg. Max. 80.1 [+0.9] Avg. Min. 61.4 [-0.4] Mean      70.8 [+0.3] 24-hour corrected mean: 69.7
Max. for month: 89F on 19th
Min. for month: 55F on 26th, 27th and 31st

COOLING DEGREE DAYS
Total heating units: 186 [0] Total for the season: 607 [+70] Total for last season: 792

PRECIPITATION, Inches
Total: 1.60 [-2.43] Greatest in 24 hrs: 1.09 on the 2nd

WIND, mph
Avg. uncorrected wind speed: 9.3
Avg. corrected wind speed: 10.0
Prevailing wind direction: S at 18%
Peak gust and direction: 33 S on 18th

SUNSHINE:
Campbell-Stokes card minutes: N/A
Astronomical total minutes: N/A

Today’s Observations:

7 A.M.
Weather: Few distant cumulus west, few altocumulus ESE-S,
few cirrus all directions
Temperature: 52F; Dew Point: 38F; Wind: NW at 10G19 kts
Sea-level pressure: 30.03 ins. Hg, rising unsteadily
Visibility: 80 miles
6-hr Max temp: 56F
6-hr Min temp: 47F
24-hr Precip: 0.00 inches
BHO SA 1155 CLR 80 168/52/38/3110G19/003/ FEW DSNT CU W FEW
AC ESE-S FEW CI ALQDS/ 8/162 52017 10056 20047

10 A.M.
Weather: Scattered cirrus, few distant cumulus WSW-NNE
Temperature: 62F; Dew Point: 40F; Wind: WNW at 11G18 kts
Sea-level pressure: 30.05 ins. Hg, rising then, more quickly
Visibility: 80 miles
BHO SA 1455 250 SCT 80 171/62/40/3011G18/005/ FEW DSNT
CU WSW-NNE/ 8/102 53003

1 P.M.
Weather: Few Cumulus ENE-WSW, few cirrus WSW-E
Temperature: 67F; Dew Point: 37F; Wind: WNW at 12G20 kts
Sea-level pressure: 30.02 ins. Hg, falling then, more quickly
Visibility: 80 miles
6-hr Max temp: 67F
6-hr Min temp: 52F
BHO SA 1755 CLR 80 166/67/37/2912G20/002/ FEW CU ENE-WSW FEW
CI WSW-E/ 8/102 56005 10067 20052

SUMMARY FOR THURSDAY, AUGUST 31, 2017

TEMPERATURE (DEGREES F)
MAX…..79   NORMAL…..76
MIN…..55   NORMAL…..59
MEAN….67   NORMAL…..68

DEPARTURE FROM 30-YEAR NORMAL…………………….-1
TOTAL DEPARTURE FOR THE MONTH……………………+11 [+0.2 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………2   DEPARTURE……….+3
TOTAL COOLING UNITS FOR THE MONTH………….186   DEPARTURE……….+0
TOTAL COOLING UNITS FOR THE SEASON…………607   DEPARTURE………+70
TOTAL COOLING UNITS LAST SEASON TO DATE…….792   DEPARTURE……..-185

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….23 NW  AT 11:34 A.M.
AERO……………………24 NW  AT 11:05 A.M.
ASOS……………………26 NW  AT 11:35 A.M.
DAVIS…………………..21 NNW AT 10:44 A.M. RMY 27
FASTEST MILE FOR YESTERDAY…………………19 NW  AT 11:04 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………20 NW  AT 11:35 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..16 NNW AT 10:46 A.M.
AVERAGE WIND SPEED AND DIRECTION…………..9.0 NNE
ASOS…………………..9.3
DAVIS………………….N/A NNW [330 DEG.]****

****DAVIS AVERAGE FROM YESTERDAY NOT AVAILABLE

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.11
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….0.00  DEPARTURE……-0.11
ASOS…………..1.58
TOTAL PRECIPITATION FOR THE YEAR……….36.36  DEPARTURE……+1.45
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR AUGUST CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST
AERO: Aerovane wind recording system 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
M:    Missing data

8/1  87/65/76/+4/0.00/762/88               16 ESE*AERO 16 NNW RMY 16
8/2  86/65/76/+4/1.09/372/43               32 W   AERO 36 W   RMY 34 TSTM
8/3  83/65/74/+2/0.00/552/64               22 S   AERO 23 S   RMY 24
8/4  84/66/75/+3/0.00/697/81               26 S   AERO 30 S   RMY 29
8/5  75/63/69/-3/0.10/060/07               23 NW  AERO 28 NW  RMY 29
8/6  76/57/67/-5/0.00/795/93               30 NW  AERO 32 NW  RMY 31
8/7  76/60/68/-4/0.01/597/70               28 SSW AERO 28 SSW RMY 29
8/8  74/60/67/-5/0.02/000/00               17 S   AERO 16 SSE RMY 16
8/9  83/58/71/-1/0.00/831/98               18 S   AERO 18 S   RMY 19
8/10 86/63/75/+4/T/643/76                  20 S   AERO 18 S   RMY 20
8/11 82/63/73/+2/0.00/666/79               17 S   AERO 16 S   RMY 17
8/12 75/57/66/-5/0.17/294/35               22 SSW*AERO 22 SSW RMY 23
8/13 84/67/76/+5/0.00/796/95               26 WNW AERO 24 WNW RMY 26
8/14 82/67/75/+4/0.00/359/43               14 SSW*AERO 14 S   RMY 15
8/15 79/64/72/+1/T/058/07                  21 S   AERO 21 S   RMY 23
8/16 83/64/74/+3/0.00/698/84               23 NW* AERO 23 NW  RMY 25
8/17 81/58/70/-1/0.00/745/90               15 SSW AERO 14 SSW RMY N/A
8/18 79/63/71/0/0.01/025/03                33 S   AERO 35 S   RMY 35
8/19 89/65/77/+7/0.00/502/61               23 WSW AERO 23 WSW RMY 25
8/20 84/66/75/+5/0.00/804/98               23 NW  AERO 25 NW  RMY 27
8/21 85/63/74/+5/0.00/687/84               18 SW  AERO 20 SW  RMY 20
8/22 88/68/78/+8/0.00/481/59               31 S   AERO 35 S   RMY 34
8/23 83/64/74/+4/0.04/642/79               24 WNW*AERO 25 WNW RMY 27
8/24 80/59/70/0/0.00/778/96                18 WNW*AERO 17 WNW RMY 21
8/25 75/57/66/-3/T/597/74                  21 NW  AERO 21 NW  RMY 23
8/26 75/55/65/-4/0.00/…/..               16 WNW AERO 16 SSE RMY 17
8/27 75/55/65/-4/0.00/…/..               17 ENE*AERO 16 ENE*RMY 18
8/28 74/56/65/-4/0.00/…/..               17 ENE AERO 16 ENE*RMY 18
8/29 68/57/63/-6/…./…/..               18 ENE AERO 16 ENE RMY N/A
8/30 72/57/65/-3/…./…/..               22 NNE AERO 21 NNE RMY 23
8/31 79/55/67/-1/0.00/…/..               23 NW  AERO 24 NW  RMY 27

DAILY RECORDS FOR AUGUST

None so far.

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST
AERO: Aerovane wind recording system 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
M:    Missing data

9/1  Low temp since midnight is 47F; normal low is now 59F

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 2.32 INCHES IN 2013
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: Kaitlin Geagan