BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, JULY 21, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
COOLER AND DRIER WEATHER RETURNS...MORNING SUNSHINE REPLACED
BY LOW CLOUDS AT MID-DAY...
The low temperature this morning of 58 was the coolest temperature
since 58 on 7/4. The dew point has dropped back to the middle 50s
today, and the visibility has climbed back up to about 70 miles. 
Low clouds are developing from the remaining moisture in the air
and are starting to fill the sky at noon.  Smoke from a fire in
Uxbridge 30-35 miles to the WSW has been visible all morning.  
Earlier, this was seen to spread in a line along the horizon 
around to the SSW with the wind from the NW, though the visible 
smoke is diminishing as of noon. 

Today's observations:
 
7 A.M.   
Weather: Scattered altocumulus, scattered dense cirrus, thin
broken cirrus fibratus
Temperature: 62F, Dew point: 54F, Wind: WNW at 9 kts 
Sea-level pressure: 29.94 inches Hg, rising
Visibility: 70 miles
6-hour min temp: 58F     
24-hour rainfall: 0.00 in.  
BHO SA 1155 150 SCT 200 SCT 250 –BKN 70 140/62/54/2909/994/ THN LN K ALG 
HRZN SSW-WSW FRM FIRE WSW 35/ 8/031 53014 10062 20058

10 A.M.   
Weather: Building scattered cumulus, scattered altocumulus and 
dense cirrus, thin broken cirrus fibratus 
Temperature: 71F, Dew point: 56F, Wind: NNW at 6 kts 
Sea-level pressure: 29.99 inches Hg, rising
Visibility: 70 miles
BHO SA 1455 35 SCT 150 SCT 200 SCT 200 –BKN 70 157/71/56/3406/999/ BLDG CU 
ALQDS THN K DSNT WSW WND LGT AND VRB/ 8/231 51017


WEATHER SUMMARY FOR FRIDAY, JULY 20
 
TEMPERATURE (DEGREES F)
MAX.....82    NORMAL.....82 
MIN.....61    NORMAL.....63
MEAN....72    NORMAL.....72
DEPARTURE FROM 30-YEAR NORMAL........0
TOTAL DEPARTURE FOR THE MONTH.......+1  (-0.1 DEGREES/DAY)
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY..............29 WSW AT 4:28 P.M.      
                   AEROVANE...............27 WSW AT 4:28 P.M.     
                   ASOS...................N/A  #
                   DAVIS..................30 W   AT 4:28 P.M.          
FASTEST MILE FOR YESTERDAY................24 WSW AT 4:29 P.M.       
MAXIMUM 2-MINUTE ASOS AVERAGE.............N/A  # 
MAXIMUM 2-MINUTE DAVIS AVERAGE............24 WSW AT 4:30 P.M.           
AVERAGE WIND SPEED AND DIRECTION........13.8 WSW  
                   ASOS...................N/A  #
                   DAVIS................13.6 WSW [228 deg]  
 
# ASOS WINDS SWITCHED OFF BY NWS 6/6, IT IS NOT KNOWN WHEN 
  THAT DATA WILL RESUME
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE.....-0.12
                         ASOS..............0.00 
TOTAL PRECIPITATION FOR THE MONTH..........1.40  DEPARTURE.....-1.02 
                         ASOS..............1.30    
TOTAL PRECIPITATION FOR THE YEAR..........28.58  DEPARTURE.....+0.29 [CORRECTED] 
                   ASOS FOR YEAR..........27.71    
 
PRELIMINARY CLIMATE SUMMARY FOR JULY 2007......CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
 
AERO: Aerovane recording wind system when significant
TSTM: Thunderstorm day
....: Data not yet available
 
7/1  70/52/61/-9/0.02/649/71/28 W      
7/2  73/50/62/-8/0/841/92/   29 WNW 
7/3  75/53/64/-6/0/839/92/   23 NW 
7/4  78/58/68/-2/0.09/465/51/45 SSE 
7/5  80/61/71/ 0/0.25/383/42/38 SSE TSTM   
7/6  83/62/73/+2/0.01/482/53/46 WNW TSTM  
7/7  81/60/71/0/0/509/56/    32 WSW   
7/8  90/62/76/+5/0.41/563/62/36 NW Aero 33 MPH TSTM 
7/9  86/61/74/+3/0.20/354/39 27 NNE TSTM
7/10 80/62/71/0/0/680/75     27 S 
7/11 84/70/77/+5/T/371/41    32 S
7/12 81/64/73/+1/.01/813/90  27 WNW
7/13 84/62/73/+1/0/695/77    36 WSW
7/14 82/62/72/0/T/765/85     33 SSE
7/15 87/65/76/+4/T/638/71    44 S  Aero 45 MPH S, Davis 48 MPH S     
7/16 84/65/75/+3/0/449/50    18 WNW 
7/17 85/65/75/+3/0/.../..    18 WNW
7/18 71/66/69/-3/0.21/000/00 23 SE   
7/19 83/65/74/+2/0.20/.../.. 31 S   
7/20 82/61/72/0/0/.../..     29 WSW

7/21 morning low temp. 58 deg; normal low now 63 deg. 

NEW DAILY RECORDS FOR JULY 2007:  

None to date

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: Mike Iacono/Eli Melaas
 
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