Tuesday, September 29, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, SEPTEMBER 29, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

TEMPS BREAK 80F ON MONDAY, TEMPERATURES AVERAGING
4.6 DEGREES ABOVE NORMAL, HEADING INTO LAST TWO
DAYS OF THE MONTH- HEAVY RAIN ON THE WAY

Abundant sunshine and a warm southerly flow yesterday
allowed temperatures to reach a peak of 81F just after
the 1:00 PM EST observation- some 14 degrees above
the daily normal maximum for that date. Overnight moisture
continued to stream up from the S, with thick fog present
at this morning’s 7:00 AM EST observation.

Fog was dissipating by the 10:00 AM EST observation, and
by 1:00 PM EST moderate cumulus and stratocumulus were
dominating the sky, with partly sunny conditions. Showers
were visible and distant in all directions. A maximum
temperature of 82F was reached by this time, which is just
3 degrees below today’s daily record of 85F set in 1952.

Today’s Observations:

7 A.M.
Weather: Thick fog
Temperature: 67F; Dew Point: 67F; Wind: S at 11 kts,
Sea-level pressure: 30.14 ins. Hg, rising slightly
Visibility: 1/4 of a mile, thick fog
6-hr Max temp: 67F
6-hr Min temp: 65F
24-hr precip: none
BHO SA 1155 W2 X 1/4F 206/67/67/1911/014/ 8//// 53002 10067 20065

10 A.M.
Weather: Scattered cumulus, broken stratocumulus, broken
cirrus
Temperature: 73F; Dew Point 69F; Wind: S at 10G16 kts,
Sea-level pressure: 30.12 ins. Hg, increasing, then decreasing and lower
Visibility: 10 miles, except 15 miles SE-SW, thin fog in all directions
BHO SA 1455 10 SCT E15 BKN 250 BKN 10 201/73/69/1810G16/012/
VSBY SE-SW 15 MI THN FG ALQDS/ 8/801 58005

1 P.M.
Weather: Scattered moderate cumulus, broken stratocumulus,
broken cirrocumulus
Temperature: 79F; Dew Point: 66F; Wind: S at 14G19 kts
Sea-level pressure: 30.07 ins. Hg, decreasing, then more slowly
Visibility: 25 miles, hazy, showers distant in all directions
6-hr Max: 82F
6-hr Min: 67F
BHO SA 1755 40 SCT E48 BKN 250 BKN 25 182/79/66/1814G19/007/
SHWRS DSNT ALQDS HAZY/ 8/809 56019 10082 20067
SUMMARY FOR MONDAY, SEPTEMBER 28, 2015

TEMPERATURE (DEGREES F)
MAX…..81   NORMAL…..67
MIN…..57   NORMAL…..50
MEAN….69   NORMAL…..58

DEPARTURE FROM 30-YEAR NORMAL…………………..+11
TOTAL DEPARTURE FOR THE MONTH………………….+135  [+4.6 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………4   DEPARTURE……….+3
TOTAL COOLING UNITS FOR THE MONTH………….135   DEPARTURE………+76
TOTAL COOLING UNITS FOR THE SEASON…………801   DEPARTURE……..+205
TOTAL COOLING UNITS LAST SEASON TO DATE…….587   DIFFERENCE…….+214

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………0   DEPARTURE……….-7
TOTAL HEATING UNITS FOR THE MONTH…………..41   DEPARTURE………-60
TOTAL HEATING UNITS FOR THE SEASON………….42   DEPARTURE………-84
TOTAL HEATING UNITS LAST SEASON TO DATE……..91   DIFFERENCE……..-49

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….22 SSW AT  4:30 P.M.*
ASOS……………………24 S   AT  4:04 P.M.
DAVIS…………………..22 SSW AT  4:03 P.M. RMY 24
FASTEST MILE FOR YESTERDAY……………….. 17 SSW AT  4:29 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………17 S   AT  4:31 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..16 SSW AT  4:30 P.M.
AVERAGE WIND SPEED AND DIRECTION…………. .10.3 SSW
ASOS……………………10.5
DAVIS……………………9.4 SSW [202 DEG]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…..0.00  DEPARTURE…..-0.14
ASOS……………0.00
TOTAL PRECIPITATION FOR THE MONTH………..1.35  DEPARTURE…..-2.41
ASOS……………1.33
TOTAL PRECIPITATION FOR THE YEAR………..31.60  DEPARTURE…..-7.17
ASOS…………….N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY 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

9/1  81/65/73/+5/0.00/766/97               20 SSW RMY 20
9/2  89/64/77/+9/0.00/732/93               20 SW  RMY 21
9/3  85/66/76/+9/T/612/78                  17 E   RMY N/A TSTM
9/4  72/58/65/-2/0.00/297/38                31 ENE RMY N/A
9/5  77/55/66/-1/0.00/748/96               14 SW  RMY 18
9/6  87/57/72/+5/0.00/753/97               21 SSW RMY 22
9/7  92/63/78/+12/0.00/727/94              23 WSW RMY 24
9/8  97/70/84/+18/0.00/693/90              22 WSW RMY 24
9/9  92/70/81/+15/0.00/683/89              30 SSW RMY 33
9/10 73/62/68/+3/…./000/00               29 NE  RMY N/A
9/11 70/59/65/0/…./084/11                33 NE  RMY N/A
9/12 75/58/67/2/…./380/50                18 SSE RMY 25
9/13 66/60/63/-1/…./000/00               25 E   RMY N/A
9/14 70/53/62/-2/0.00/550/73               33 W   RMY 35
9/15 82/56/69/+5/0.00/736/98               23 W   RMY N/A
9/16 84/62/73/+10/0.00/711/95              17 NW  RMY N/A
9/17 87/64/76/+13/0.00/723/97              17 SW  RMY 16
9/18 86/64/75/+13/0.00/712/96              21 SSW RMY 21
9/19 80/62/71/+9/0.00/…/..               22 S   RMY N/A
9/20 74/55/65/+3/T/…./…                24 S   RMY N/A
9/21 65/50/58/-3/0.00/…/..               29 ENE RMY 30
9/22 67/55/61/+0/0.00/…/..               21 E   RMY 21
9/23 72/50/61/+1/0.00/…/..               15 E   RMY N/A
9/24 72/56/64/+4/0.00/…/..               22 E   RMY 21
9/25 66/53/60/0/0.00/…/..                21 E   RMY 20
9/26 63/49/56/-3/0.00/…/..               25 ENE RMY 25
9/27 71/46/59/+0/0.00/…/..               17 S   RMY 18
9/28 81/57/69/+11/0.00/…/..              22 SSW RMY 24

9/29 low since midnight is 65F; normal low is now 49F

DAILY RECORDS FOR SEPTEMBER 2015

**9/7 DAILY RECORD MAXIMUM TEMPERATURE OF 92F
TIES PREVIOUS RECORD SET IN 2007**

**9/8 DAILY RECORD MAXIMUM TEMPERATURE OF 97F
BREAKS PREVIOUS RECORD OF 93F SET IN 2007**

**9/8 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 70F
BREAKS PREVIOUS RECORD OF 69F SET IN 1999**

**9/9 DAILY RECORD MAXIMUM TEMPERATURE OF 92F
BREAKS PREVIOUS RECORD OF 91F SET IN 2002**

**9/9 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 70F
BREAKS PREVIOUS RECORD OF 69F SET IN 1999**

**9/17 DAILY RECORD MAXIMUM TEMPERATURE OF 87F
BREAKS PREVIOUS RECORD OF 86F SET IN 1915, 1941, AND 1991**

**9/18 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 64F
TIES PREVIOUS RECORD SET IN 1992**

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

RECORDS FOR SEPTEMBER 29
HIGH 85F IN 1952
LOW 28F IN 1914 (SEPTEMBER MINIMUM RECORD)
PRECIP 2.61 INCHES IN 1907
PEAK GUST 62 MPH S IN 2005

RECORDS FOR SEPTEMBER 30
HIGH 84F IN 1986
LOW 31F IN 1992
PRECIP 1.93 INCHES IN 1946
PEAK GUST 58 MPH SSE IN 1999

TODAY’S REPORT PREPARED BY: Brian Fitzgerald