Friday, July 13, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, JULY 13, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

QUIET WEATHER CONTINUES

It has been another quiet weather day on Blue Hill, with dry conditions
and seasonably mild temperatures. The morning low was slightly cooler than
average at 61F, and the afternoon high so far is 83F, which is a couple
degrees above average. Skies were partly to mostly cloudy early this morning,
turned mostly clear for the mid-morning hours, and have become partly cloudy
again this afternoon with cumulus clouds popping up. Winds have been very
light for a second day in a row, not gusting past 20mph. Visibility has
been typical for summertime, mostly in the 40-50 mile range with some haze.

Today’s Observations:

7 A.M.
Weather: Broken altocumulus castellanus, few stratus fractus distant SE-S,
few lower altocumulus, thin smoke layer along horizon ESE-SE and NW-NNE
Temperature: 66F; Dew Point: 60F; Wind: SSE at 7 kts
Sea-level pressure: 30.27 ins. Hg, rising then more slowly
Visibility: 55 miles
6-hr Max temp: 66F
6-hr Min temp: 61F
24-hr Precip: 0.00 ins.
BHO SA 1155 E100 BKN 55 252/66/60/1607/027/ FEW STFRA DSNT SE-S
FEW LWR AC THN K LYR ALG HRZN ESE-SE AND NW-NNE/ 8/78/ 51011 10066 20061

10 A.M.
Weather: Mostly clear, few cumulus distant SE-NW, few altocumulus
castellanus distant offshore ENE-E, few cirrus distant SW-NW
Temperature: 77F; Dew Point: 58F; Wind: SE at 10 kts,
Wind: Direction variable E-S
Sea-level pressure: 30.26 ins. Hg, rising then falling
Visibility: 40 miles, distant haze
3-hr Precip: 0.00 ins.
BHO SA 1455 CLR 40 247/77/58/1410/026/ FEW CU DSNT SE-NW
FEW ACC DSNT OFFSHR ENE-E FEW CI DSNT SW-NW DSNT HZ WND 10V18/ 8/181 58005

1 P.M.
Weather: Scattered cumulus, scattered cirrus, few moderate cumulus
distant N, few altocumulus castellanus distant offshore ENE-E
Temperature: 82F; Dew Point: 55F; Wind: S at 8 kts,
Wind: Direction variable SSE-SW
Sea-level pressure: 30.22 ins. Hg, falling then more slowly
Visibility: 45 miles, distant haze
6-hr Max temp: 83F
6-hr Min temp: 66F
6-hr precip: 0.00 ins.
BHO SA 1755 45 SCT 250 SCT 45 233/82/55/1808/022/ FEW MDT CU DSNT N
FEW ACC DSNT OFFSHR ENE-E DSNT HZ WND 15V22/ 8/281 56014 10083 20066

SUMMARY FOR THURSDAY, JULY 12, 2018

TEMPERATURE (DEGREES F)
MAX…..77   NORMAL…..81
MIN…..56   NORMAL…..63
MEAN….67   NORMAL…..72

DEPARTURE FROM 30-YEAR NORMAL…………………….-5
TOTAL DEPARTURE FOR THE MONTH……………………+44 [+3.9 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………2   DEPARTURE……….-5
TOTAL COOLING UNITS FOR THE MONTH………….119   DEPARTURE………+41
TOTAL COOLING UNITS FOR THE SEASON…………278   DEPARTURE………+71
TOTAL COOLING UNITS LAST SEASON TO DATE…….302   DEPARTURE………-24

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..16 NW  AT 1:57 A.M.*
AERO…………………….15 NW  AT 1:50 A.M.
ASOS…………………….17 NW  AT 1:51 A.M.
DAVIS……………………17 NNW AT 1:51 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………….13 NNW AT 3:28 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….14 NNW AT 3:29 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………13 N   AT 3:28 A.M.
AVERAGE WIND SPEED AND DIRECTION……………8.4 ENE
ASOS……………………8.4
DAVIS…………………..8.7 ENE [61 deg.] * Last of multiple occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.13
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.29  DEPARTURE……-0.09
ASOS…………..1.31
TOTAL PRECIPITATION FOR THE YEAR……….31.46  DEPARTURE……+3.29
ASOS………….33.04

PRELIMINARY CLIMATE SUMMARY FOR JULY 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

7/01 94/72/83/+13/0.00/…/..       21 ESE AERO 18 ESE RMY 19
7/02 90/68/79/+9/0.00/…/..        21 S   AERO 21 S   RMY 22
7/03 94/69/82/+11/0.00/…/..       20 SSW AERO 18 SW  RMY 19 TSTM
7/04 89/73/81/+10/0.00/…/..       17 NE  AERO 15 NE  RMY 16
7/05 91/73/82/+11/0.00/…/..       29 SSW AERO 28 SSW RMY N/A
7/06 80/59/70/-1/0.56/…/..        37 NNW AERO 38 SW  RMY 40 TSTM
7/07 78/54/66/-5/0.00/…/..        22 N   AERO 18 N   RMY N/A
7/08 83/57/70/-2/0.00/…/..        23 S   AERO 21 S   RMY 22
7/09 88/60/74/+2/0.00/…/..        23 SW  AERO 23 SW  RMY 24
7/10 91/63/77/+5/…./…/..        24 W   AERO 22 W   RMY N/A
7/11 73/62/68/-4/…./…/..        28 NE  AERO 25 NE  RMY 27 TSTM
7/12 77/56/67/-5/0.00/…/..        16 NW  AERO 15 NW  RMY N/A

7/13 Low temp since midnight is 61F; normal low is now 63F

DAILY RECORDS FOR JULY 2018

07/01/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 72F,
TIES PREVIOUS RECORD OF 72F SET IN 1968

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

RECORDS FOR JULY 13
HIGH 95F IN 1894
LOW 52F IN 1888, 1895, 1939, 1973
PRECIP 3.54 INS IN 1996
WIND 55 MPH SE IN 1996

RECORDS FOR JULY 14
HIGH 98F IN 1952
LOW 51F IN 1895, 1937
PRECIP 1.97 INS IN 1960
WIND 110e MPH NW IN 1942 [THUNDERSTORM GUST; RECORD FOR MONTH]

TODAY’S REPORT PREPARED BY: Jonathan O’Brien and Samantha Richard