BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, JULY 20, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
LOW CLOUDS AND THIN EARLY MORNING FOG HAVE GIVEN WAY TO PARTIAL 
SUNSHINE THROUGH 2PM. A WARM HUMID NIGHT HAS GIVEN WAY TO FALLING 
DEWPOINTS, DRIER AIR, AND WINDS BACKING TOWARD THE WEST AS A WEAK 
COLD FRONT BEGAN PUSHING THROUGH THE REGION.
 
The summer sunshine and the approach of a weak cold front has pushed
out the low clouds and muggy air.  Mid-morning at the observatory
saw the low level moisture rising to form several towering cumulus that
were topped by distinct pileus or "cap" clouds.  The coming weekend
should yield lots of sunshine and seasonable temperatures.
 
Today's observations:
 
7 A.M.   
Weather: Thin fog, overcast
Temperature: 71F, Dew point: 70F, Wind: SSW at 16G21 kts 
Sea-level pressure: 29.64 inches Hg, rising
Visibility: 3 miles
6-hour min temp: 70F     
24-hour rainfall: 0.20 in.  
BHO SA 1155 E5 OVC 3F 037/71/70/2016G21/964/ 
TF OVC STFRA 8/6// 53005 MANUAL 70020 ASOS 70019 10072 20070
 
10 A.M.   
Weather: Small cumulus, broken altocumulus and cirrus 
Temperature: 78F, Dew point: 70F, Wind: WSW at 12G20 kts 
Sea-level pressure: 29.69 inches Hg, rising
Visibility: 40 miles
BHO SA 1455 040 SCT E150 BKN 250 BKN 40 054/78/70/2512G20/969/ 
SM CU ALQDS TWRG CU E-SSE PILEUS ABV TWRG CU E BKN AC SCT CI NW/
8/221 53017
 
1 P.M.   
Weather: Moderate cumulus, broken altocumulus and cirrus 
Temperature: 79F, Dew point: 62F, Wind: WSW at 14 kts 
Sea-level pressure: 29.72 inches Hg, rising
Visibility: 45 miles   
6-hourly max. temp: 81 deg.  
BHO SA 1755 50 SCT E130 BKN 250 OVC 45 063/79/62/2414G20/972/ 
MDT CU BKN AC OVHD CI NW/ 8/221 53009 10081 20072
 
WEATHER SUMMARY FOR THURSDAY, JULY 19
 
TEMPERATURE (DEGREES F)
MAX.....83    NORMAL.....82 
MIN.....65    NORMAL.....63
MEAN....74    NORMAL.....72
DEPARTURE FROM 30-YEAR NORMAL.......+2
TOTAL DEPARTURE FOR THE MONTH.......+1  (+0.1 DEGREES/DAY)
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY..............31 S   AT  7:37 P.M.      
                   AEROVANE...............30 S   AT  7:37 P.M.     
                   ASOS...................N/A  #
                   DAVIS..................33 S   AT  7:47 P.M.          
FASTEST MILE FOR YESTERDAY................23 S   AT  7:38 P.M.       
MAXIMUM 2-MINUTE ASOS AVERAGE.............N/A  # 
MAXIMUM 2-MINUTE DAVIS AVERAGE............21 S  AT   8:04 P.M.           
AVERAGE WIND SPEED AND DIRECTION.........9.6 S  
                   ASOS...................N/A  #
                   DAVIS.................9.3 S  [184 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... 0.20  DEPARTURE.....+0.09
                         ASOS..............0.19 
TOTAL PRECIPITATION FOR JULY...............1.40  DEPARTURE.....-0.90 
                         ASOS..............1.30    
TOTAL PRECIPITATION FOR THE YEAR..........28.18  DEPARTURE.....+0.41 
                   ASOS FOR YEAR..........27.52    
 
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 morning low temp. 70 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 20
HIGH 99F IN 1991
LOW 47F IN 1890
PRE 1.64 INS IN 1938
WIND 56e MPH SSW IN 1943
 
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

TODAY'S REPORT PREPARED By: Eli Melaas/Nate Magee