Monday, September 13, 2021

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

MONDAY, SEPTEMBER 13, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0522E
SUNSET:  1757E
 
EARLY MORNING CLOUDS AND SHOWERS GIVE WAY TO BRIGHT SUNSHINE
AND PLEASANT TEMPERATURES….

Showers and thunderstorms moved through the region early this
morning ahead of a cold front that slipped through by mid
morning. Rainfall was mainly light here on the hill, amounting
to only 0.06″. However heavier rain and even thunder was
observed to our north across the North Shore area, where even
some severe weather occurred.

Following the showers and storm, clearing skies moved in with
a west-northwesterly breeze taking over. This afternoon has seen
abundant sunshine with only some cumulus clouds decorating the
sky.

Visibility has improved markedly, from 35 miles this morning to
70 miles early this afternoon.

The high so far today is 76F, this is 2 degrees above the
daily normal maximum of 74F. The low so far today is 65F,
which is 8 degrees above the daily normal minimum of 57F.


PRELIMINARY STATS FOR AUGUST 2021

TEMPERATURE, Deg. F
Avg. Max. 81.6 [+1.4]
Avg. Min. 65.4 [+2.8]
Mean      73.5 [+2.1]
24-hour corrected mean: 72.6
Max. for month: 92F on the 13th
Min. for month: 58F on the 1st

HEATING DEGREE DAYS
Total heating units:      0 [-11]
Total for the season:    28 [+25]
Total for last season:    3

COOLING DEGREE DAYS
Total cooling units:     271 [+62]
Total for the season:    650 [+54]
Total for last season:   757

PRECIPITATION, Inches
Total: 5.37 [+1.46]
Greatest in 24 hrs: 2.38 ins. on the 4th-5th  

WIND, mph
Avg. uncorrected wind speed:  8.8 mph
Avg. corrected wind speed:    9.5 mph
Prevailing wind direction:   SSW [14%]
Peak gust and direction:     47 ESE on the 22nd

SUNSHINE:
Campbell-Stokes card minutes: 12612 minutes of a possible 24780, or 51%
Astronomical total minutes: 13116 minutes of a possible 25728, or 51%

Today’s Observations:

7 A.M.
Weather: Scattered stratocumulus, overcast altostratus, few breaks in
overcast distant NE-ENE, few lower stratus fractus all quadrants
Temperature: 65F; Dew Point: 64F; Relative Humidity: 97%
Wind: NNW @ 9G15 kts
Sea-level pressure: 1015.9 mb; 30.00 in. Hg; falling then rising
Visibility: 35 miles  
6-hr Max temp: 70F
6-hr Min temp: 65F
24-hr Precip: 0.06 ins.
BHO SA 1155 50 SCT E100 OVC 35 159/65/64/3409G15/000/ FEW BINOVC DSNT NE-ENE
FEW LWR STFRA AQLDS RW-E27/ 8/72/ 53018 6006/ 70006 10070 20065

10 A.M.
Weather: Scattered stratocumulus, thin broken cirrus
Temperature: 70F; Dew Point: 63F; Relative Humidity: 79%
Wind: NW @ 7 kts
Sea-level pressure: 1016.8 mb; 30.03 in Hg; steady then rising
Visibility: 50 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 45 SCT E250 -BKN 50 168/70/63/3207/003/ 8/501 53009

1 P.M.
Weather: Scattered cumulus, thin scattered cirrus
Temperature: 75F, Dew point: 63F; Relative Humidity: 67%
Wind: WNW @ 6 kts
Sea-level pressure: 1016.1 mb; 30.01 in Hg; falling, then more slowly
Visibility: 70 miles
6-hr Max temp: 76F
6-hr Min temp: 65F
6-hr Precip: 0.00 ins.
BHO SA 1755 35 SCT 250 -SCT 70 161/75/63/3006/001/ 8/101 56007 10076 20065

SUMMARY FOR SUNDAY, SEPTEMBER 12, 2021

TEMPERATURE (DEGREES F)
MAX…….79     NORMAL…..74
MIN…….60     NORMAL…..57
MEAN……70     NORMAL…..66

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL………….+4
TOTAL DEPARTURE FOR THE MONTH……………………-14 [-1.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2021 THRU JUN 2022)
TOTAL HEATING UNITS FOR YESTERDAY…………….0  DEPARTURE……..-2
TOTAL HEATING UNITS FOR THE MONTH……………10  DEPARTURE……..-8
TOTAL HEATING UNITS FOR THE SEASON…………..38  DEPARTURE……..+2
TOTAL HEATING UNITS LAST SEASON TO DATE………10  DEPARTURE…….+28

COOLING DEGREE DAYS (SEASON: JAN 2021 THRU DEC 2021)
TOTAL COOLING UNITS FOR YESTERDAY…………….5  DEPARTURE……..+2
TOTAL COOLING UNITS FOR THE MONTH……………25  DEPARTURE…….-21
TOTAL COOLING UNITS FOR THE SEASON………….675  DEPARTURE…….+33
TOTAL COOLING UNITS LAST SEASON TO DATE……..805  DEPARTURE……-130

PEAK WIND GUST (MPH):
                     Official……………….33 SW  @ 10:23 A.M.
                     AEROVANE (south tower)…..32 SW  @ 10:23 A.M.
                     VECTOR #2 (south tower)….37     @  7:32 A.M.
                     DAVIS #2 (south tower)…..33 SW  @ 10:24 A.M.
                     ASOS………..OUT OF SERVICE D/T RENOVATIONS
                     VECTOR #1……OUT OF SERVICE D/T RENOVATIONS
                     DAVIS #1…….OUT OF SERVICE D/T RENOVATIONS
                     RMY…………OUT OF SERVICE D/T RENOVATIONS  
                     MERLIN………OUT OF SERVICE D/T RENOVATIONS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………24 SW   @ 11:45 A.M.*
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..19      @  3:26 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………19 WSW  @  1:29 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE…….OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE…OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE..OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE RMY AVERAGE……..OUT OF SERVICE D/T RENOVATIONS
*LAST OF TWO OCCURRENCES

AVERAGE WIND SPEED AND DIRECTION:
                     CONTACTING/OFFICIAL…….15.0 SW [361 total miles]
                     VECTOR #2……………..15.7
                     DAVIS #2………………15.5 SW
                     RMY……………..OUT OF SERVICE D/T RENOVATIONS
                     ASOS…………….OUT OF SERVICE D/T RENOVATIONS
                     VECTOR #1………..OUT OF SERVICE D/T RENOVATIONS
                     DAVIS #1…………OUT OF SERVICE D/T RENOVATIONS   

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.06  DEPARTURE….-0.07
TOTAL PRECIPITATION FOR THE MONTH………….5.04  DEPARTURE….+3.60
TOTAL PRECIPITATION FOR THE YEAR………….45.38  DEPARTURE….+9.59

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

08/01   77/58/68/-5/T/589/68             23 SSW AERO 24 SSW RMY N/A
08/02   78/61/70/-3/T/821/95             28 WNW AERO 28 WNW RMY N/A
08/03   76/60/68/-5/0.00/302/35          15 N   AERO 16 N   RMY N/A
08/04   75/61/68/-5/0.71/077/09          21 ESE AERO 21 ESE RMY N/A
08/05   68/61/65/-8/1.68/000/00          28 NE  AERO 28 NE  RMY N/A
08/06   85/62/74/+1/0.00/727/85          19 S   AERO 20 WSW RMY N/A
08/07   88/66/77/+4/0.00/520/61          23 SW  AERO 23 SW  RMY N/A
08/08   80/67/74/+2/T/128/15             16 SW  AERO 16 WNW RMY N/A
08/09   75/64/70/-2/0.25/076/09          22 ENE AERO 21 NE  RMY N/A
08/10   78/63/71/-1/0.12/203/24          19 S   AERO 20 S   RMY N/A
08/11   89/70/80/+8/0.00/667/79          29 SSW AERO 28 SSW RMY N/A
08/12   91/71/81/+9/T/580/69             36 WSW AERO 37 WSW RMY N/A TSTM
08/13   92/73/83/+11/0.00/696/83         18 WSW AERO 18 WSW RMY N/A
08/14   87/69/78/+6/T/601/72             25 W   AERO 25 NNW RMY N/A
08/15   80/62/71/-1/0.00/800/96          19 NNW AERO 20 NNW RMY N/A
08/16   78/59/69/-3/0.00/564/68          15 S   AERO 15 S   RMY N/A
08/17   82/63/73/1/0.00/555/67           22 SSW AERO 23 SSW RMY N/A
08/18   86/66/76/+5/0.00/338/41          21 SSW AERO 22 SSW RMY N/A
08/19   81/69/75/+4/0.62/222/27          41 S   AERO 43 S   RMY N/A
08/20   78/70/74/+3/0.01/066/08          21 WSW AERO N/A    RMY N/A
08/21   86/69/78/+7/0.00/581/71          17 S   AERO 17 S   RMY N/A
08/22   74/66/70/-1/0.78/000/00          47 ESE AERO 48 ESE RMY N/A
08/23   83/68/76/+5/1.17/333/41          25 SSE AERO 26 SSE RMY N/A TSTM
08/24   86/67/77/+6/0.01/567/70          21 NNW AERO 21 NNW RMY N/A
08/25   89/70/80/+10/0.00/783/97         17 SW  AERO 18 SW  RMY N/A
08/26   92/72/82/+12/0.00/765/95         19 WSW AERO 18 WSW RMY N/A
08/27   89/70/80/+10/T/626/78            30 ENE AERO 30 ENE RMY N/A
08/28   70/59/65/-5/0.02/296/37          34 ENE AERO 34 ENE RMY N/A
08/29   72/59/66/-4/T/016/02             20 S   AERO 21 S   RMY N/A
08/30   84/67/76/+7/0.00/246/31          25 SW  AERO 26 SW  RMY N/A
08/31   80/65/73/+4/0.00/371/47          27 WNW AERO 28 WNW RMY N/A

RECORDS FOR THE MONTH

08/22 NEW PEAK GUST RECORD OF 47 MPH,
      BEATING THE OLD RECORD OF 44 MPH IN 1987

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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

09/01   68/56/62/-7/1.47/000/00          34 NNE AERO 37 NNE RMY N/A    
09/02   71/55/63/-6/2.53/322/41          49 ENE AERO 52 ENE RMY N/A
09/03   72/52/62/-6/0.00/735/94          23 NW  AERO 23 NW  RMY N/A
09/04   76/55/66/-2/0.00/757/97          22 WNW AERO 21 WNW RMY N/A
09/05   72/60/66/-2/0.04/008/01          27 S   AERO 29 S   RMY N/A
09/06   80/61/71/+3/0.00/…/..          24 WNW AERO 25 WNW RMY N/A
09/07   78/57/68/+1/0.00/…/..          23 WSW AERO 22 WSW RMY N/A
09/08   81/61/71/+4/0.00/…/..          43 S   AERO 45 S   RMY N/A
09/09   71/64/68/+1/0.90/…/..          33 S   AERO 36 S   RMY N/A
09/10   74/55/65/-1/0.04/…/..          31 NW  AERO 32 WNW RMY N/A
09/11   75/51/63/-3/0.00/…/..          24 SW  AERO 24 SW  RMY N/A
09/12   79/60/70/+4/0.00/…/..          33 SW  AERO 32 SW  RMY N/A

09/13  The low since midnight is 65F, the daily normal low is 57F

DAILY EXTREMES

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

RECORDS FOR SEPTEMBER 13
HIGH 91F IN 1957
LOW 40F IN 1985
PRECIP 3.10 INCHES IN 1987
PEAK GUST 44 MPH WNW IN 1986

RECORDS FOR SEPTEMBER 14
HIGH 90F IN 1931
LOW 34F IN 1911
PRECIP 2.90 INCHES IN 1944 (Great Atlantic Hurricane in 1944)
PEAK GUST 96e MPH E IN 1944 (Great Atlantic Hurricane in 1944)

TODAY’S REPORT PREPARED BY: Matt Douglas