Friday, August 21, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, AUGUST 21, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

RAIN SHOWERS, FOG AND RUMBLES OF THUNDER
TO START FRIDAY MORNING

Overnight temperatures barely dipped after sunset
to a low of 71F, some 10 degrees above today’s daily
normal low. Rain showers of varying intensity began
this morning at 6:05 AM EST, with a few rumbles of
thunder overhead beginning at 8:10 AM EST.

Intermittent showers and fog have remained in place
throughout the morning, with showers and thunderstorms
developing by the 1:00 PM EST observation. A cumulonimbus
developed E of the station and was moving NNE with showers
falling from NNE to SSE of the station. Numerous light
to moderate rain showers this morning and early afternoon
had amounted to 0.13 inches of new rain so far today.
Today’s Observations:

7 A.M.
Weather: Partial obscuration of fog, light rain showers,
overcast stratus, stratus fractus in all directions drifting
below the summit
Temperature: 72F; Dew Point: 72F; Wind: SE at 9 kts
Sea-level pressure: 30.04 ins. Hg, rising, then more slowly
Visibility: 5 miles, except 2 miles NE, 4 miles SW, obscured
by partial fog and rain showers
6-hr Max temp: 73F
6-hr Min temp: 72F
24-hr precip: 0.04 ins.
BHO SA 1155 E2 OVC X- 5RW-F 173/72/72/1509/004/ RW-B05 VSBY 2 MI NE
4 MI SW STFRA DRFTG BLW SMT ALQDS/ 8/7// 51008 ASOS 60003 70003
MANUAL 60004 70004 10073 20072

10 A.M.
Weather: Intermittent Fog, overcast stratus, stratus
fractus drifting below the summit in all directions
Temperature: 74F; Dew Point 74F; Wind: S at 8 kts,
Sea-level pressure: 30.05 ins. Hg, rising, then more slowly
Visibility: 4 miles, except 3/4 of a mile N-ENE, obscured
by intermittent fog
3-hr precip: 0.06 ins.
BHO SA 1455 E3 OVC X- 4F 177/74/74/1708/005/ VSBY N-ENE 3/4 MI STRFRA
DRFTG BLW SMT ALQDS  FG INTMT SUN DMLY VSBL/ 8/7// 51004 ASOS 60007
MANUAL 60006

1 P.M.
Weather: Light rain shower beginning 12:28, ending 12:49 PM EST,
cumulonimbus E moving NNE, showers distant NNE-SSE, towering cumulus
N and SE, scattered cumulus, broken altocumulus, broken cirrocumulus
Temperature: 80F; Dew Point: 74F; Wind: estimated SSE at 5 kts
Wind Speed: Light
Sea-level pressure: 30.04 ins. Hg, steady, then falling
Visibility: 30 miles, except 10 miles NNE-SSE, obscured by showers,
hazy
6-hr Max temp: 81F
6-hr Min temp: 72F
6-hr precip: 0.09 ins.
BHO SA 1755 20 SCT E70 BKN 250 BKN 30 172/80/74/E1605/004/ RW-B28E49
CB DSNT E MOV NNE VSBY NNE-SSE 15 MI SHWRS DSNT NNE-SSE TCU N AND SE
HAZY WND LGT/ 8/339 58005 ASOS 60009 MANUAL 60009 10081 20072
SUMMARY FOR THURSDAY, AUGUST 20, 2015

TEMPERATURE (DEGREES F)
MAX…..85   NORMAL…..79
MIN…..70   NORMAL…..62
MEAN….78   NORMAL…..70

DEPARTURE FROM 30-YEAR NORMAL……………………+8
TOTAL DEPARTURE FOR THE MONTH…………………..+60  [+2.8 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..13   DEPARTURE……….+7
TOTAL COOLING UNITS FOR THE MONTH………….187   DEPARTURE………+54
TOTAL COOLING UNITS FOR THE SEASON…………581   DEPARTURE………+97
TOTAL COOLING UNITS LAST SEASON TO DATE…….427   DIFFERENCE…….+154

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….22 ESE AT   3:52 P.M.
ASOS……………………23 ESE AT   3:52 P.M.
DAVIS…………………..21 ESE AT   3:51 P.M. RMY 22
FASTEST MILE FOR YESTERDAY…………………15 ESE AT   3:49 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………15 ESE AT   3:52 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..15 ESE AT   3:52 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..9.2 SSE
ASOS…………………..9.0
DAVIS………………….8.4 SSE [156 deg.] * Last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…..0.04  DEPARTURE…..-0.09
ASOS……………0.03
TOTAL PRECIPITATION FOR THE MONTH………..2.44  DEPARTURE…..-0.31
ASOS…………..2.45
TOTAL PRECIPITATION FOR THE YEAR………..29.80  DEPARTURE…..-3.94
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR AUGUST 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

8/1  88/68/78/+6/0.06/729/84               28 WNW RMY N/A
8/2  86/62/74/+2/0.00/865/100              24 SW  RMY N/A
8/3  89/68/79/+7/0.00/690/80               31 S   RMY N/A
8/4  86/66/76/+4/0.31/422/49               45 W   RMY 50  TSTM
8/5  84/64/74/+2/0.00/765/89               28 WNW RMY 27
8/6  80/59/70/-2/0.00/685/80               22 W   RMY 21
8/7  78/61/70/-2/0.00/845/99               20 ESE RMY 18
8/8  77/58/68/-4/0.00/741/87               18 E   RMY N/A
8/9  72/59/66/-6/T/458/54                  27 NNE RMY 26
8/10 84/58/71/0/0.00/…/..                28 S   RMY N/A
8/11 70/63/67/-4/0.52/000/00               32 SSE RMY 35
8/12 83/65/74/+3/0.00/766/91               22 W   RMY 20
8/13 83/62/73/+2/0.00/832/99               18 WNW RMY 18
8/14 86/63/75/+4/0.00/837/100              21 S   RMY 23
8/15 91/66/79/+8/…./…/..               38 W   RMY 41  TSTM
8/16 87/65/76/+5/…./…/..               16 W   RMY N/A
8/17 90/70/80/+9/0.00/…/..               17 W   RMY 18
8/18 92/70/81/+10/0.27/…/..              31 W   RMY 32  TSTM
8/19 87/69/78/+8/0.00/…/..               23 S   RMY 24
8/20 85/70/78/+8/0.00/…/..               22 ESE RMY 22

8/21 low since midnight is 72F; normal low is now 61F

DAILY RECORDS FOR AUGUST 2015
None so far.

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

RECORDS FOR AUGUST 21
HIGH 92F IN 1937, 1995
LOW 47F IN 1982
PRECIP 2.84 INCHES IN 1888
PEAK GUST 54 MPH WSW IN 2004

RECORDS FOR AUGUST 22
HIGH 90F IN 1939
LOW 42F IN 1894
PRECIP 2.28 INCHES IN 1935
PEAK GUST 44 MPH SSW IN 1987

TODAY’S REPORT PREPARED BY: Brian Fitzgerald