BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, JULY 21, 2009
ALL TIMES ARE IN EASTERN STANDARD TIME
 
OVERCAST VERY COOL AND WET LATE JULY DAY
TEMPS. HOLD IN LOWER 60'S--NEAR RECORD JULY CHILL
LIGHT RAIN TOTALS ONLY A QUARTER OF AN INCH
 
Thick cloud cover with rain and northeast winds
are holding temperatures at near record cool
levels for mid to late July.  Today's high
reading of 66F occurred very early this morning
but readings have held between 62F and 63F
since 8 a.m. EDT and continue at 62F early
this afternoon. Today's record low maximum
temperature is 64F in 1902 and 1936. So, it
is certainly record cool for a mid-July afternoon 
around this date although not a new record
for the 24-hour record.  
Light rain continues and has amounted to close
to one quarter of an inch by early afternoon.
 
Today's observations:
 
7 A.M.  
Weather: Broken stratocumulus, overcast nimbostratus,
present weather light rain and fog 
Temperature: 63F, Dew point: 62F, Wind: NNE at 11 kts,
Wind: direction variable N to ENE  
Sea-level pressure: 30.24 inches Hg, rising
Visibility: 5 miles, 8 miles to southwest
6-hour minimum temp: 62F
6-hourly rainfall: 0.04 inch
24-hourly rainfall: 0.04 inch 
BHO SA 1155 E38 BKN 75 OVC 5R-F 241/63/62/0311/024/
VSBY SW 8/ 8/52/ 50001 ASOS 60004 MANUAL 6004/
ASOS 70004 MANUAL 70004 10066 20062
 
10 A.M.
Weather: Scattered stratus fractus, overcast nimbostratus,
present weather light rain 
Temperature: 62F, Dew point: 62F, Wind: NE at 13 kts,
Wind: direction variability NW to ENE 
Sea-level pressure: 30.24 inches Hg, steady
Visibility: 4 miles
BHO SA 1455 6 SCT E28 OVC 4R-F 241/62/62/0413/024/
FEW STFRA DRFTG BLO SMT WND 35V07/ 8/72/ 55000
ASOS 60005 MANUAL 6006/
 
1 P.M.  
Weather: Obscurement with fog, present weather
light rain and dense fog 
Temperature: 62F, Dew point: 62F, Wind: NNE at 15G22 kts,
Wind: direction variable N thru ENE 
Sea-level pressure: 30.21 inches Hg, falling
Visibility: 1/16 mile
6-hourly max. temp. 63F
BHO SA 1755 W2 X 1/16R-F 229/62/62/0315G22/021/
WND 35V07/ 8//// 58012
ASOS 60022 MANUAL 6023/ 10063 20062
 
WEATHER SUMMARY FOR MONDAY, JULY 20
 
TEMPERATURE (DEGREES F)
MAX.....80    NORMAL.....82
MIN.....64    NORMAL.....63
MEAN....72    NORMAL.....72
 
DEPARTURE FROM 30-YEAR AVERAGE.......... 0
TOTAL DEPARTURE FOR THE MONTH..........-85  [-4.5 DEGREES/DAY]
 
HEATING DEGREE DATA WILL RESUME IN SEPTEMBER
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY.............16 E   AT  2:14 P.M. 
                   AEROVANE..............13 E   AT  2:14 P.M.   
                   ASOS..................14 ENE AT  2:35 P.M.    
                   DAVIS.................14 E   AT  2-3  P.M.   
FASTEST MILE FOR YESTERDAY...............10 E   AT  2:52 P.M. * 
MAXIMUM 2-MINUTE ASOS AVERAGE............10 E   AT  3:51 P.M.   
MAXIMUM 2-MINUTE DAVIS AVERAGE...........11 E   AT  2:53 P.M.   
AVERAGE WIND SPEED AND DIRECTION....... 6.5 E
                   ASOS.................6.4
                   DAVIS................6.5 NE [050 DEG]
 
* last of several occurrences...
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.04  DEPARTURE....-0.08
                         ASOS..............0.04
TOTAL PRECIPITATION FOR THE MONTH..........3.49  DEPARTURE....+1.07
                         ASOS..............3.56 
TOTAL PRECIPITATION FOR THE YEAR..........27.17  DEPARTURE....-0.96
                         ASOS.............28.21
 
PRELIMINARY CLIMATE SUMMARY FOR JULY 2009 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane wind recording system gust when significant
TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized
 
7/1  62/57/60/-10/0.51/000/00   25 NNE   TSTM
7/2  66/56/61/-9/1.00/000/00    29 SSW   TSTM
7/3  75/58/67/-3/T/283/31       23 WSW
7/4  77/59/68/-2/0/838/92       43 W      
7/5  78/54/66/-5/0/856/94       33 W     
7/6  79/60/70/-1/0/883/97       20 SSE
7/7  66/58/62/-9/0.73/027/03    28 SE    TSTM
7/8  67/56/62/-9/0.23/091/10    27 NNE   TSTM
7/9  66/55/61/-10/0/689/76      23 NE
7/10 76/54/65/-6/0/896/99       21 SW
7/11 77/56/67/-5/0.29/686/76    36 S
7/12 78/60/69/-3/0.33/650/72    30 SSW   TSTM
7/13 76/55/66/-6/0/802/89       32 SW 
7/14 75/56/66/-6/0/567/63       25 WNW
7/15 79/55/67/-5/0/826/92       30 WSW
7/16 77/62/70/-2/T/161/18       30 S
7/17 86/65/76/+4/0.01/582/65    24 ESE
7/18 84/66/75/+3/0.35/447/50    25 SSW   TSTM
7/19 80/62/71/-1/0/865/97       27 WSW
7/20 80/64/72/0/0/.../..        16 E
 
7/21 our morning low temp: 62F; the normal low is now 63F
 
NEW DAILY RECORDS FOR JULY 2009 TO DATE...
NONE
 
DAILY EXTREMES
 
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR JULY 21
HIGH 100F IN 1977 [RECORD FOR MONTH]
LOW 48F IN 1890
PRECIP 2.09 INCHES IN 1938
PEAK GUST 60e MPH WNW IN 1977
 
RECORDS FOR JULY 22
HIGH 99F IN 1926
LOW 52F IN 1890
PRECIP 1.73 INCHES IN 1900
PEAK GUST 55 MPH IN 1983
 
TODAY'S REPORT PREPARED BY: Robert Skilling