BLUE HILL METEOROLOGICAL OBSERVATORY 
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, JULY 21, 2011  
ALL TIMES ARE IN EASTERN STANDARD TIME
 
HEAT WAVE ENTERS REGION WITH HIGH HUMIDITY AND HAZE
 
Heat wave entered region this morning with a recorded
morning temperature of 74F at 8 AM EDT. Dew points have
stayed in the 70s today as temperatures continue to rise. Haze has
persisted throughout the day reducing visibility.
Temperatures continue to rise, with a 2:00 PM EDT reading
of 92F and a heat index of 104F. Expect high temperatures
to reach the low to mid 90s at lower elevations. Heat wave
will continue to persist through Saturday. An expected cold
front on Sunday will help return seasonable temperatures in
the low to mid 80s early next week.
  
Below are listed record values for the expected heat
 
Current Blue Hill Record High Temperatures:
July 21     100F    1977
July 22     99F     1926
July 23     99F     1952
 
Today's observations:
 
7 A.M.  
Weather: Scattered stratus, dissipating past hour,
thin overcast cirrus and cirrostratus, thin fog/haze
Temperature: 74F, Dew point: 71F; Wind: S at 12 kts
Sea-level pressure: 29.80 inches Hg, rising 
Visibility: 5 miles, thin fog and haze
6-hour min. temp: 68F
BHO SA 1155 3 SCT 250 –OVC 5FH 092/74/71/1912/980/
STRA DSPTNG PST HR 8/607 58003 10074 20068
 
10 A.M.
Weather: Scattered cirrus, thin broken cirrus
Temperature: 85F, Dew Point: 74F;  Wind: SSW at 13G20 kts
Wind: Direction variable S-WSW
Sea-level pressure: 29.74 inches Hg, falling 
Visibility: 10 miles, hazy 
BHO SA 1455 250 SCT 300 –BKN 10 077/85/74/2013G20/974/
FEW CC OVHD HAZY WND 18V24/ 8/001 58015
 
1 P.M.
Weather: Thin scattered cirrus, distant lower cirrus NE, few
cumulus fractus/cumulus forming all quadrants except N-E. Few
altocumulus standing lenticular forming SW-NW-NE
Temperature: 92F, Dew Point: 74F;  Wind: SSW at 18G25 kts
Peak wind SSW at 28 kts 39 minutes past the hour.
Wind: Direction variable S-SW
Sea-level pressure: 29.71 inches Hg, falling
Visibility: 9 miles, hazy 
6-hour max. temp: 92F
BHO SA 1755 300 –SCT 9 061/92/74/2018G25/971/ FEW CUFRA/CU
FRMG XCPT N-E FEW ACSL FRMG SW-NW-NE LWR CI DSNT NE HAZY PK WND
2028/39/ WND 17V23 8/141 58016 10092 20074
 
 
WEATHER SUMMARY FOR WEDNESDAY, JULY 20
 
TEMPERATURE (DEGREES F)
MAX.....88    NORMAL.....82
MIN.....69    NORMAL.....63
MEAN....79    NORMAL.....72
 
DEPARTURE FROM 30-YEAR NORMAL....................+7
TOTAL DEPARTURE FOR THE MONTH...................+57 [+2.6 DEGREES/DAY]
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY..............29 SSW AT 4:46 P.M.
                   AEROVANE...............36 SSW AT 4:20 P.M.
                   ASOS...................32 SW  AT 4:53 P.M.
                   DAVIS..................34 SSW AT 5:20 P.M.
THE FASTEST MILE FOR YESTERDAY............24 SSW AT 4:19 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE.............24 SSW AT 4:21 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE............25 S   AT 5:21 P.M.
AVERAGE WIND SPEED AND DIRECTION........11.4 SSW
                   ASOS.................11.4
                   DAVIS................10.5 S [190 deg]
 
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..........1.73  DEPARTURE.........-0.69
                         ASOS..............1.71
TOTAL PRECIPITATION FOR THE YEAR..........29.04  DEPARTURE.........+0.95
                        ASOS..............29.57**
**ASOS data is in error due to system failure on 1/12-13
 
PRELIMINARY CLIMATE SUMMARY FOR JULY 2011 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  78/59/69/-1/0.01/530/58         15 WNW 
7/2  80/61/71/+1/0.00/603/66         17 SE
7/3  79/64/72/+2/0.02/018/02         22 S
7/4  86/68/76/+6/0.00/583/64         18 SW
7/5  89/66/78/+7/0.00/784/86         15 S
7/6  88/68/78/+7/T/792/87            30 WNW AERO 35 MPH TSTM
7/7  86/67/77/+6/0.00/481/53         17 WNW
7/8  74/65/70/-1/0.47/027/03         16 ESE TSTM
7/9  81/63/72/+1/0.11/698/77         29 WNW  
7/10 83/59/71/0/0.00/860/95          21 SSW
7/11 89/65/77/+5/0.00/814/90         23 S
7/12 90/72/83/+9/0.00/777/86         25 W
7/13 85/61/73/+1/0.73/469/52         21 NE
7/14 70/58/64/-8/0.37/801/89         28 NNE TSTM 
7/15 79/59/69/-3/0.00/692/77         17 SSW TSTM 
7/16 85/61/73/+1/0.00/834/93         15 SW
7/17 88/67/78/+6/0.00/797/89         30 SSW
7/18 84/70/77/+5/0.02/188/21         38 WSW AERO 43 MPH
7/19 86/69/78/+6/0.00/777/87         18 WNW AERO 24 MPH
7/20 88/69/79/+7/0.00/.../..         29 SSW
 
7/21 our morning low 68F; normal low is now 63F
 
DAILY RECORDS FOR JULY 2011
None so far...
 
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/ George Tabeek