Thursday, July 16, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, JULY 16, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

COLD FRONT CLEARED OUT FOG AND HUMIDITY LAST EVENING
MUCH COOLER, DRIER AIR MASS TODAY WITH SUNSHINE
THROUGH JUST SOME HIGH THIN CLOUDS AND NE WINDS
RAIN SHOWERS EARLY LAST EVENING BROUGHT 0.11 INCH

There was a dramatic change in air mass last night
preceded by a few showers in the early evening. The
dew point dropped from the mid-60’s early last evening
to near 50 degrees early this morning.

Today’s Observations:

7 A.M.
Weather: Thin scattered cirrus, thin broken cirrus, stratocumulus
forming NE-S, few lower cirrocumulus, cirrocumulus lenticularis
Temperature: 60F; Dew Point: 51F; Wind: NE at 10 kts,
Wind: Gust to 18 kts past hour
Sea-level pressure: 30.04 ins. Hg, rising then rising more slowly
Visibility: 60 miles, except 70 NW, light distant haze
6-hr Max temp: 61F
6-hr Min temp: 56F
24-hr precip: 0.11 inch
BHO SA 1155 250 –SCT 300 –BKN 60 173/60/51/0310/004/ SC FRMG NE-S
FEW LWR CC/CCSL VSBY NW 70 LGT DSNT HZ WND GST 18 KTS PST HR/
8/501 51023 MANUAL 70011 ASOS 70010 10061 20056

10 A.M.
Weather: Thin scattered cirrus, cumulus/cumulus fractus mostly
distant SE-SW-N, patches dense cirrus NW
Temperature: 64F; Dew Point 50F; Wind: ENE at 11 kts,
Wind: Gust 22 kts past hour
Sea-level pressure: 30.06 rising then more slowly
Visibility: 60 miles, except 70 miles NW, light distant haze
BHO SA 1455 250 -SCT 60 180/64/50/0711/006/ CU/CUFRA MSTLY
DSNT SE-SW-N PTCHS DNS CI NW VSBY NW 70 LGT DSNT HZ WND GST
22 KTS PST HR/ 8/102 51007

1 P.M.
Weather: Scattered cirrus (2 levels)
Temperature: 68F; Dew Point: 51F; Wind: estimated E at 4 kts,
Wind: Light
Sea-level pressure: 30.05 ins. Hg, falling slightly
Visibility: 60 miles, light distant haze
6-hr Max temp: 69F
6-hr Min temp: 60F
BHO SA 1755 220 SCT 250 SCT 60 178/68/51/E0904/005/ OCNL CUFRA
VC S-SW CU DSNT SW-NNE THN CI DSNT E-SSE LGT DSNT HZ WND LGT/
8/101 58002 10069 20060

SUMMARY FOR WEDNESDAY, JULY 15, 2015

TEMPERATURE (DEGREES F)
MAX…..84   NORMAL…..81
MIN…..61   NORMAL…..63
MEAN….73   NORMAL…..72

DEPARTURE FROM 30-YEAR NORMAL……………………+1
TOTAL DEPARTURE FOR THE MONTH…………………..+13 [+0.7 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………8   DEPARTURE……….+1
TOTAL COOLING UNITS FOR THE MONTH………….109   DEPARTURE……….+9
TOTAL COOLING UNITS FOR THE SEASON…………247   DEPARTURE………+18
TOTAL COOLING UNITS LAST SEASON TO DATE…….247   DIFFERENCE……….0

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….24   ENE  AT   5:13 P.M.
ASOS……………………26   ENE  AT   5:13 P.M.
DAVIS…………………..25   NE   AT   5:13 P.M. RMY 26
FASTEST MILE FOR YESTERDAY…………………16   NE   AT   5:18 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………18   ENE  AT   5:18 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..16   NE   AT   5:18 P.M.
AVERAGE WIND SPEED AND DIRECTION……………7.5  NE
ASOS……………………8.0
DAVIS…………………..6.4  NE  [040 deg.] * Last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…..0.11  DEPARTURE…..-0.03
ASOS……………0.10
TOTAL PRECIPITATION FOR THE MONTH………..2.82  DEPARTURE…..+1.02
ASOS……………2.85
TOTAL PRECIPITATION FOR THE YEAR………. 27.09  DEPARTURE…..-1.68
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR JULY 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

7/1  80/63/72/+2/0.59/…/..               30 SSE RMY 33  TSTM
7/2  78/60/69/-1/0.00/…/..               23 WNW RMY N/A
7/3  79/58/69/-2/0.00/…/..               17 SSW RMY 17
7/4  74/61/68/-3/T/…/..                  16 S   RMY N/A
7/5  82/58/70/-1/0.00/…/..               20 WSW RMY 20
7/6  85/64/75/+4/0.00/…/..               20 S   RMY 21
7/7  84/65/75/+4/0.02/…/..               35 S   RMY 40
7/8  87/68/78/+6/T/…/..                  23 NE  RMY N/A
7/9  73/61/67/-5/…./…/..               24 NE  RMY 25
7/10 80/59/70/-2/…./…/..               18 W   RMY N/A TSTM
7/11 84/61/73/+1/0.00/…/..               21 NW  RMY 19
7/12 88/67/78/+6/0.00/…/..               20 W   RMY 17
7/13 82/66/74/+2/0.00/…/..               21 E   RMY 20
7/14 81/64/73/+1/…./…/..               25 S   RMY 27
7/15 84/61/73/+1/…./…/..               24 ENE RMY 26

7/16 since midnight is 56F; normal low is now 63F

DAILY RECORDS FOR JULY 2015

7/10- NEW RECORD DAILY PRECIPITATION PENDING OF X.XX in 2015
surpasses previous record of 1.68 in. in 1933

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

RECORDS FOR JULY 16
HIGH 94F IN 1968, 1980, 1983, 1999
LOW 50F IN 1889, 1903
PRECIP 0.97 INS IN 2014
WIND 48e MPH SW 1944

RECORDS FOR JULY 17
HIGH 96F IN 1999
LOW 47F IN 1892
PRECIP 1.39 INS IN 1989
WIND 46 MPH WNW IN 1971

TODAY’S REPORT PREPARED BY: Robert Skilling