Sunday, October 21, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, OCTOBER 21, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

COOL, WINDY DAY ON TOP OF GREAT BLUE HILL….

So far today, we have reached a high temperature of 45F,
14 degrees below our normal maximum temperature of 59F.
Winds have frequently gusting over 20 knots since around
5 A.M., with a maximum wind speed so far of 36 knots
experienced at 12:55 EST this afternoon. Our low since
midnight was 41F, the same as our normal minimum temperature.
Fog in the area early this morning reduced visibility to 20
miles, which increased to 70 miles at our 10 A.M. observation
as the fog cleared, and to 80 miles by 1 P.M.

Today’s Observations:

7 A.M.
Weather: Overcast stratus, light rain
Temperature: 41F; Dew Point: 37F; Wind: NNW at 10G20 kts
Sea-level pressure: 29.73 ins. Hg, rising then more quickly
Visibility: 20 miles, distant fog
6-hr Max temp: 47F
6-hr Min temp: 41F
24-hr Precip: 0.03 ins.
BHO SA 1155 E55 OVC 20 069/41/37/3310G20/973/ R-CTD DSNT FOG
ALQDS/ 8/600 70003 53039 10047 20041

10 A.M.
Weather: Scattered stratocumulus, broken cirrus
Temperature: 42F; Dew Point: 29F; Wind: NW at 16G30 kts
Peak Wind: 34 WSW at 9:14 A.M.
Sea-level pressure: 29.78 ins. Hg, rising then more slowly
Visibility: 70 miles
3-hr Precip: 0.02 ins.
BHO SA 1455 70 SCT E220 BKN 70 085/42/29/3216G30/978/ FEW
CU ALQDS PK WND 3234/14/ 8/158 6002/ 51016

1 P.M.
Weather: Broken stratocumulus
Temperature: 43F; Dew Point: 23F; Wind: NW at 18G36 kts
Peak wind: 36 kts at 12:55
Sea-level pressure: 29.81 ins. Hg, rising unsteadily
Visibility: 80 miles
6-hr Max temp: 46F
6-hr Min temp: 40F
6-hr Precip: 0.02 ins.
BHO SA 1755 E45 BKN 80 095/43/23/3218G36/981/ PK WND
3236/55/ 8/400 6002/ 51010 10046 20040

SUMMARY FOR SATURDAY, OCTOBER 20, 2018

TEMPERATURE (DEGREES F)
MAX…..62   NORMAL…..59
MIN…..46   NORMAL…..41
MEAN….54   NORMAL…..50

DEPARTURE FROM 30-YEAR NORMAL…………………..+4
TOTAL DEPARTURE FOR THE MONTH………………….+36 [+1.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..11   DEPARTURE………-4
TOTAL HEATING UNITS FOR THE MONTH………….203   DEPARTURE……..-33
TOTAL HEATING UNITS FOR THE SEASON…………290   DEPARTURE……..-88
TOTAL HEATING UNITS LAST SEASON TO DATE…….195   DIFFERENCE…….+95

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0  DEPARTURE………..0
TOTAL COOLING UNITS FOR THE MONTH…………..11  DEPARTURE……….+6
TOTAL COOLING UNITS FOR THE SEASON…………874  DEPARTURE……..+272
TOTAL COOLING UNITS LAST SEASON TO DATE…….727  DIFFERENCE…….+147

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..35 SSW AT 5:51 A.M.
AERO…………………….37 SSW AT 5:56 A.M.
ASOS…………………….37 SW  AT 5:54 A.M.
DAVIS……………………34 SSW AT 5:54 A.M. RMY 33
FASTEST MILE FOR YESTERDAY………………….28 SSW AT 5:53 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….25 SSW AT 5:55 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………26 SSW AT 2:32 A.M.
AVERAGE WIND SPEED AND DIRECTION…………..14.7 SSW
ASOS…………………..14.3
DAVIS………………….14.7 WSW [244 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.15
ASOS…………..0.01
TOTAL PRECIPITATION FOR THE MONTH……….2.79  DEPARTURE……-0.34
ASOS…………..2.77
TOTAL PRECIPITATION FOR THE YEAR……….49.99  DEPARTURE……+7.96
ASOS………….51.69

PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 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

10/01 65/53/59/+2/…./042/06         21 ENE AERO 18 SSW RMY N/A
10/02 64/53/59/+2/…./000/00         33 S   AERO 32 S   RMY 35 TSTM
10/03 60/52/56/0/…./000/00          18 NNE AERO 14 NNE RMY 14
10/04 69/57/63/+7/…./209/30         29 SSW AERO 29 SSW RMY 32
10/05 64/47/56/0/…./638/92          25 NE  AERO 21 NE  RMY 24
10/06 64/45/55/0/0.00/276/40          23 SSW AERO 23 SSW RMY 25
10/07 75/56/66/+11/…./076/11        28 NE  AERO 24 ENE RMY 27
10/08 56/53/55/+1/…./000/00         22 ENE AERO 20 ENE RMY N/A
10/09 75/56/66/+12/…./211/31        26 WSW AERO 28 SW  RMY 29
10/10 82/65/74/+20/…./496/73        24 WSW AERO 23 WSW RMY 25
10/11 70/56/63/+10/…./…/..        48 NNE AERO 47 NNE RMY 50
10/12 59/44/52/-1/…./…/..         32 NW  AERO 32 NW  RMY 33
10/13 49/40/45/-8/…./…/..         21 WNW AERO 20 WNW RMY 20
10/14 55/37/46/-6/…./…/..         21 W   AERO 18 W   RMY 21
10/15 66/44/55/+3/…./…/..         46 W   AERO 46 W   RMY N/A
10/16 56/41/49/-2/…./…/..         48 W   AERO 48 W   RMY N/A
10/17 60/39/50/-1/…./…/..         48 W   AERO 50 W   RMY 53
10/18 45/33/39/-12/…./…/..        32 WNW AERO 35 WNW RMY 36
10/19 60/31/46/-4/…./…/..         33 SSW AERO 36 SSW RMY 36
10/20 62/46/54/+4/…./…/..         35 SSW AERO 37 SSW RMY 33

10/21 Low temp since midnight is 41F; normal low is 41F

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

RECORDS FOR OCTOBER 21
HIGH 79F IN 1979
LOW 24F IN 1974
PRECIP 2.39 INCHES IN 1944
SNOWFALL TRACE IN 1895,1907,1940
PEAK GUST 69e MPH S IN 1976

RECORDS FOR OCTOBER 22
HIGH 85F IN 1979
LOW 22F IN 1940
PRECIP 2.38 INCHES IN 2014
SNOWFALL TRACE IN 1969, 2010
PEAK GUST 67 MPH ESE IN 1988

TODAY’S REPORT PREPARED BY: Samantha Richard