Tuesday, September 22, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, SEPTEMBER 22, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

COOL TEMPERATURES REMAIN IN PLACE FOR TUESDAY,
WINDS GUST TO NEAR 30 MPH ON COOLER THAN NORMAL MONDAY

**BLUE HILL OBSERVATORY KICKSTARTER CAMPAIGN NEARLY
HALFWAY TO RAISING FUNDS TO REPLACE OUR BELFORT AEROVANE
ANEMOMETER. PLEASE MAKE A TAX-DEDUCTIBLE DONATION
TODAY SO WE CAN MAKE THIS CRITICAL INSTRUMENT PURCHASE:**

Temperatures failed to hit the 70F degree mark for only the
second time this month, as temperatures topped out at 65F. Overnight
temperatures dipped to a near seasonable level at 55F.

Mostly cloudy skies were present to start the day this morning,
with a sea breeze from the NNE. By today’s 1:00 PM EST observation
some breaks of clouds along with thin high cirrus allowed for
partly sunny skies to prevail. A maximum temperature of 67F
had been recorded by that time.
Today’s Observations:

7 A.M.
Weather: Scattered altocumulus, overcast altostratus,
sun dimly visible
Temperature: 57F; Dew Point: 52F; Wind: NNE at 9 kts,
Sea-level pressure: 30.35 ins. Hg, rising unsteadily
Visibility: 60 miles, thin fog
6-hr Max temp: 57F
6-hr Min temp: 55F
24-hr precip: none
BHO SA 1155 160 SCT E200 OVC 60 276/57/52/0309/035/
FEW CU DSNT E THN FG ALQDS SUN DMLY VSBL/ 8/11/ 52010
10057 20055

10 A.M.
Weather: Scattered stratocumulus, scattered altocumulus,
broken altostratus, broken cirrus
Temperature: 64F; Dew Point 57F; Wind: NE at 9G16 kts,
Sea-level pressure: 30.35 ins. Hg, rising, then more slowy
Visibility: 65 miles, light distant haze
BHO SA 1455 40 SCT 160 SCT E200 BKN 250 BKN 65
278/64/57/0509G16/035/ LGT DSNT HZ ALQDS/ 8/451 51002

1 P.M.
Weather: Few cumulus/stratocumulus in all directions,
scattered altocumulus, broken cirrus/cirrocumulus
Temperature: 66F; Dew Point: 53F; Wind: ENE 9G18 kts.
Sea-level pressure: 30.33 ins. Hg, falling, then more quickly
Visibility: 65 miles, light distant haze
6-hr Max: 67F
6-hr Min: 57F
BHO SA 1755 160 SCT E250 BKN 65 272/66/53/0609G18/033/
FEW SC/CU ALQDS LGT DSNT HZ ALQDS/ 8/839 58006 10067 20057
SUMMARY FOR MONDAY, SEPTEMBER 21, 2015

TEMPERATURE (DEGREES F)
MAX…..65   NORMAL…..70
MIN…..50   NORMAL…..53
MEAN….58   NORMAL…..62

DEPARTURE FROM 30-YEAR NORMAL……………………-3
TOTAL DEPARTURE FOR THE MONTH………………….+123  [+5.7 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0   DEPARTURE……….-1
TOTAL COOLING UNITS FOR THE MONTH………….131   DEPARTURE………+79
TOTAL COOLING UNITS FOR THE SEASON…………797   DEPARTURE……..+208
TOTAL COOLING UNITS LAST SEASON TO DATE…….571   DIFFERENCE…….+226

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………7   DEPARTURE……….+2
TOTAL HEATING UNITS FOR THE MONTH…………..12   DEPARTURE………-45
TOTAL HEATING UNITS FOR THE SEASON………….13   DEPARTURE………-69
TOTAL HEATING UNITS LAST SEASON TO DATE……..63   DIFFERENCE……..-50

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….29  ENE AT  3:25 P.M.
ASOS……………………31  NE  AT  3:25 P.M.
DAVIS…………………..28  ENE AT  3:24 P.M. RMY 30
FASTEST MILE FOR YESTERDAY…………………21  NE  AT  3:27 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………21  NE  AT  3:28 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..19  NE  AT  3:29 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..12.3 NNE
ASOS…………………..11.6
DAVIS………………….10.9 NE [053 DEG]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…..0.00  DEPARTURE…..-0.15
ASOS……………0.00
TOTAL PRECIPITATION FOR THE MONTH………..1.35  DEPARTURE…..-1.38
ASOS……………1.33
TOTAL PRECIPITATION FOR THE YEAR………..31.60  DEPARTURE…..-6.14
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  72/58/65/0/0.00/297/38                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 low since midnight is 55F; normal low is now 52F

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 22
HIGH 90F IN 1895, 1914
LOW 30F IN 1904 (Earliest freeze)
PRECIP 1.16 INCHES IN 2001
PEAK GUST 60 MPH SSW IN 1989

RECORDS FOR SEPTEMBER 23
HIGH 93F IN 1895,1914
LOW 33F IN 1904
PRECIP 2.67 INCHES IN 1994
PEAK GUST 62 MPH SSW IN 1989

TODAY’S REPORT PREPARED BY: Brian Fitzgerald