BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, OCTOBER 16, 2012 
ALL TIMES ARE IN EASTERN STANDARD TIME
 
COLD FRONT PASSES THROUGH OVERNIGHT;
MUCH COOLER, DRIER, AND SUNNIER TODAY
 
A strong cold front swept through the area overnight, making its passage
past the summit just before midnight EST.  The frontal passage was quite
apparent with a dramatic wind direction shift from S to W in just a few
minutes.  A few light rain showers and one very brief downpour associated
with the front brought 0.06 inch of rainfall late last night and early
this morning.
 
Temperatures steadily dropped after the front came through, reaching
a minimum around 7:30 AM EST of 47F.  This afternoon, the afternoon high
has struggled to reach the mid 50s.  However, the high temperature for
the day of 61F actually occurred very early this morning just as the
temperature began its steady drop.  Dew point temperatures have dropped
into the mid 30s, providing visibility in the 75-80 mile range.
 
The W wind has been quite gusty at times today, reaching a peak of
38 mph on several occasions.
 
Today's observations:
 
7 A.M.
Weather: Scattered cumulus, broken stratocumulus, broken altocumulus
(2 levels), few cumulus and stratocumulus distant SSW-NNW, altocumulus
lenticularis all quadrants except ESE-S, line altocumulus castellanus
distant WSW-W, line of clearing SSW-NNW moving E, virga ESE-SSE and NW
Temperature: 48F; Dew Point: 41F; Wind: W at 17G25 kts.
Sea-level pressure: 29.62 ins. Hg, rising 
Visibility: 65 miles, N-E-S 50 miles, NW 80 miles
6-hour precip: 0.01 inch
24-hour precip: 0.06 inch
6-hour max. temp: 58F
6-hour min. temp: 48F
BHO SA 1155 30 SCT E60 BKN 80 BKN 100 BKN 65 029/48/41/2817G25/962/
FEW CU AND SC DSNT SSW-NNW ACSL ALQDS XCPT ESE-S LINE ACC DSNT WSW-W
LINE CLRG SSW-NNW MOVG E VIRGA ESE-SSE AND NW VSBY N-E-S 50 NW 80/ 8/580
53010 MANUAL 60001 ASOS 60002 MANUAL 70006 ASOS 70005 10058 20048
 
10 A.M. 
Weather: Scattered cumulus, scattered altocumulus, scattered thin cirrus,
few patches of stratocumulus W-N, few altocumulus lenticularis SW-WNW
Temperature: 51F; Dew Point: 37F; Wind: W at 18G29 kts,
Wind: Direction variable WSW-NNW
Wind: Peak wind from the WSW at 32 kts. at 9:33 A.M. EST
Sea-level pressure: 29.64 ins. Hg, rising 
Visibility: 75 miles 
BHO SA 1455 30 SCT 100 SCT 250 –SCT 75 036/51/37/2818G29/964/ FEW PTCHS
SC W-N FEW ACSL SW-WNW WND 24V33 PK WND 2932/33/ 8/541 50007
 
1 P.M. 
Weather: Scattered cumulus, scattered altocumulus, cumulus all quadrants,
altocumulus along horizon NNE-ESE, thin smoke/haze layer distant all
quadrants, light distant haze
Temperature: 53F; Dew Point: 35F; Wind: WNW at 19G27 kts,
Wind: Direction variable WSW-NNW
Wind: Peak wind from the WNW at 33 kts. at 12:39 P.M. EST
Sea-level pressure: 29.64 ins. Hg, rising slightly
Visibility: 75 miles, light distant haze
6-hour max. temp: 54F
6-hour min. temp: 47F
BHO SA 1755 40 SCT 100 SCT 75 037/53/35/3019G27/964/ CU ALQDS AC ALG
HRZN NNE-ESE THN K/HZ LYR DSNT ALQDS LGT DSNT HZ WND 25V33
PK WND 3033/39/ 8/170 50001 10054 20047
 
WEATHER SUMMARY FOR MONDAY, OCTOBER 15
 
TEMPERATURE (DEGREES F)
MAX.....73   NORMAL.....61
MIN.....58   NORMAL.....43
MEAN....66   NORMAL.....52
 
DEPARTURE FROM 30-YEAR NORMAL....................+14
TOTAL DEPARTURE FOR THE MONTH....................+11 [+0.5 DEGREE/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY.............0    DEPARTURE.......-13
TOTAL HEATING UNITS FOR THE MONTH...........149    DEPARTURE.......-15
TOTAL HEATING UNITS FOR THE SEASON..........248    DEPARTURE.......-58
TOTAL HEATING UNITS LAST SEASON TO DATE.....168    DIFFERENCE......+80
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY.............43 SSW AT 11:23 A.M.
                   AERO..................43 SSW AT 11:23 A.M.
                   ASOS..................43 SSW AT 11:24 A.M.
                   DAVIS.................42 SSW AT 11:24 A.M. RMY 43
THE FASTEST MILE FOR YESTERDAY...........33 SSW AT 11:24 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE............33 SSW AT 11:25 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE...........34 SSW AT 11:24 A.M.
AVERAGE WIND SPEED AND DIRECTION.......20.0 S
                   ASOS................18.5
                   DAVIS...............18.9 SSW [196 deg]
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.06   DEPARTURE...........-0.09
                         ASOS..............0.05
TOTAL PRECIPITATION FOR THE MONTH..........0.98   DEPARTURE...........-1.24
                         ASOS..............0.93	
TOTAL PRECIPITATION FOR THE YEAR..........29.60   DEPARTURE..........-11.70
                         ASOS.............29.48
 
PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 2012 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane wind recording system gust
RMY:  RMY = R.M. Young wind gust recording system added 8/9/2011
TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized
 
10/1  66/47/57/0/T/429/61             36 W   AERO 35 MPH WSW RMY 36
10/2  69/53/61/+4/0.12/098/14         18 W   AERO 16 MPH W   RNT 16
10/3  62/58/60/+4/0.02/000/00         20 NE  AERO 18 MPH NE  RMY 18
10/4  61/58/60/+4/0.08/000/00         17 NNE AERO 14 MPH NE  RMY 14
10/5  75/57/66/+10/0.00/623/90        20 SW  AERO 19 MPH SW  RMY 21
10/6  77/48/63/+8/0.20/269/39         36 SSW AERO 37 MPH SSW RMY 36 TSTM
10/7  57/44/51/-4/0.15/185/27         21 WNW AERO 18 MPH WNW RMY 19
10/8  55/40/48/-6/0.00/328/48         17 WNW AERO 15 MPH WNW RMY N/A
10/9  56/49/53/-1/T/000/00            27 E   AERO 25 MPH ENE RMY 25
10/10 60/47/54/0/0.22/000/00          36 WNW AERO 36 MPH WNW RMY 31
10/11 58/41/50/-3/0.00/668/99         35 WNW AERO 33 MPH WNW RMY 34
10/12 51/34/43/-10/0.04/.../..        32 WNW AERO 30 MPH NW  RMY 30
10/13 52/29/41/-12/0.00/.../..        22 SSW AERO 20 MPH WNW RMY N/A
10/14 66/43/55/+3/0.09/.../..         40 SW  AERO 39 MPH SW  RMY 39
10/15 73/58/66/+14/0.03/.../..        43 SSW AERO 43 MPH SSW RMY 43
 
10/16 morning low temp: 47F; the normal low is now 43F
 
DAILY RECORDS FOR OCTOBER 2012
10/13 - NEW DAILY RECORD LOW MINIMUM TEMPERATURE OF 29F;
        surpasses previous record of 30F set in 1934, 1936, 1988
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR OCTOBER 16
HIGH 86F IN 1897
LOW 28F IN 1886
PRECIP 2.82 INCHES IN 1974
SNOWFALL TRACE IN 2009
PEAK GUST 68e MPH SSE IN 1954 (HURRICANE HAZEL)
 
RECORDS FOR OCTOBER 17
HIGH 86F IN 1947
LOW 25F IN 1886
PRECIP 1.87 INCHES IN 1989
SNOWFALL TRACE IN 1970
PEAK GUST 55 MPH NE IN 1964
 
TODAY'S REPORT PREPARED BY: Sean Fankhauser