BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, OCTOBER 21, 2009  
ALL TIMES ARE IN EASTERN STANDARD TIME
 
EARLY MORNING CLOUDS CLEAR AWAY LEAVING US
WITH BRIGHT SUNSHINE AND CONTINUED WARMER WEATHER
AND HIGH TEMPERATURES REACH 60'S FOR A SECOND DAY
 
The early morning clouds cleared away and a much milder
air mass continued to arrive today. After a rather
mild overnight low of 48 degrees temperatures have
reached at least the middle 60's this afternoon.
The day will likely average about 8 degrees warmer
than normal.
 
Today's observations:
 
7 A.M.
Weather: Broken altocumulus stratiformis duplicatus
Temperature: 50F, Dew point: 44F, Wind: WNW at 8 kts,
Wind: Direction gradually veering past hour
Sea-level pressure: 30.18 inches Hg, rising
Visibility: 25 miles, hazy, lower below inversion
6-hour minimum temp: 48F
BHO SA 1155 E130 BKN 25 220/50/44/2908/018/
HAZY VSBY LWR BLO INVSN WND GRDL VEERING PST HR/
8/070 53008 10051 20048 
 
10 A.M.
Weather: Scattered altocumulus translucidus decreasing  
Temperature: 58F, Dew point: 44F, Wind: W at 4 kts,
Wind: Light 
Sea-level pressure: 30.18 inches Hg, falling
Visibility: 35 miles, west-northwest 45 miles,
and northeast to southeast 30 miles, hazy 
BHO SA 1455 110 SCT 25 220/58/44/2604/018/
AC DSSPTNG HAZY WND LGT/ 8/030 50000
 
1 P.M.   
Weather: Clear, cumulus forming ESE-SW-N few moderate tops
to the west-northwest to northwest, cirrus distant S-SW and
distant NW-N 
Temperature: 66F, Dew point: 46F, Wind: W at 6 kts,
Wind: Light 
Sea-level pressure: 30.14 inches Hg, falling
Visibility: 35 miles, 30 miles NE-SE, 45 miles west-northwest   
6-hour maximum temp: 66F
BHO SA 1755 CLR 35 206/66/46/2706/014/ CU FRMG ESE-SW-N
FEW MDT WNW-NW CI DSNT S-SW AND DSNT NW-N VSBY WNW 45
NE-SE 30 HAZY WND LGT/ 8/201 58014 10066 20050 
 
WEATHER SUMMARY FOR TUESDAY, OCTOBER 20
 
TEMPERATURE (DEGREES F)
MAX.....65     NORMAL.....59
MIN.....38     NORMAL.....42
MEAN....52     NORMAL.....50
 
DEPARTURE FROM 30-YEAR AVERAGE...........+2
TOTAL DEPARTURE FOR THE MONTH...........-89 [-4.7 DEGREES/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY............13  DEPARTURE.......-2
TOTAL HEATING UNITS FOR THE MONTH...........321  DEPARTURE......+84
TOTAL HEATING UNITS FOR THE SEASON..........478  DEPARTURE......+72
TOTAL HEATING UNITS LAST SEASON TO DATE.....337  DIFFERENCE....+141
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY.............23 W   AT   6:52 P.M. * 
                   AEROVANE..............22 E   SY   6:17 P.M.    
                   ASOS..................22 W   AT   6:52 P.M.    
                   DAVIS.................23 WSW AT   1:29 P.M.  
FASTEST MILE FOR YESTERDAY...............16 W   AT   6:51 P.M.  
MAXIMUM 2-MINUTE ASOS AVERAGE............17 W   AT   6:52 P.M.   
MAXIMUM 2-MINUTE DAVIS AVERAGE...........17 W   AT   6:52 P.M.  
AVERAGE WIND SPEED AND DIRECTION.......11.0 W 
                   ASOS................10.7 
                   DAVIS...............10.5 WSW [250 DEG]
* last of several occurrences...
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00   DEPARTURE....-0.14
                         ASOS..............0.00
TOTAL PRECIPITATION FOR MONTH..............4.53   DEPARTURE....+1.73
                         ASOS..............4.50
TOTAL PRECIPITATION FOR THE YEAR..........42.41   DEPARTURE....+2.01
                         ASOS.............43.56
 
PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 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
 
10/1  56/39/48/-9/0/155/22     27 WSW 
10/2  60/40/50/-6/0/442/63     23 SSE 
10/3  63/51/57/+1/1.10/000/00  32 ESE  AERO 30 MPH ESE 
10/4  67/57/62/+6/0/202/29     21 WSW
10/5  64/49/57/+2/0/595/86     33 W    AERO 31 MPH W
10/6  65/45/55/0/0/628/91      25 W
10/7  67/51/59/+4/0.70/344/50  54 W    AERO 54 MPH W
10/8  61/48/55/+1/0/602/88     43 W    AERO 39 MPH W
10/9  60/48/54/0/0.05/000/00   29 SSE
10/10 62/42/52/-2/0.26/205/30  37 NW
10/11 61/39/50/-3/0/655/97     35 WSW  AERO 33 MPH W 
10/12 53/36/45/-8/T/471/70     23 SSW
10/13 51/36/44/-8/0.20/074/11  35 WNW 
10/14 52/32/42/-10/0/494/74    27 NW
10/15 41/32/37/-15/0.19/000/00 29 NNE
10/16 41/33/37/-14/0.24/000/00 37 NNE  AERO 35 MPH NNE T SNOW
10/17 48/33/41/-10/0/250/38    35 NNE
10/18 46/32/39/-12/1.79/000/00 43 NNE  SNOWFALL 3.0 INS
10/19 52/33/43/-8/0/.../..     25 NNW
10/20 65/38/52/+2/0/.../..     23 W
 
10/21 our morning low temp: 48F; the normal low is now 41F
 
NEW DAILY RECORDS FOR OCTOBER 2009
10/7: NEW RECORD WIND GUST 54 MPH W AT 2005E;
      surpasses previous record of 52 MPH ESE in 1972
10/15: NEW RECORD LOW MAXIMUM TEMPERATURE 41;
      surpasses previous 47 set in 1887 and 1896
10/16: NEW RECORD LOW MAXIMUM TEMPERATURE 41;
      surpasses previous 42 set in 1940
10/18: NEW RECORD DAILY SNOWFALL 3.0 INS; 
      surpasses previous trace in 1972
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR OCTOBER 21
HIGH 79 IN 1979
LOW 24 IN 1974
PRECIP 2.39 INCHES IN 1944
SNOWFALL TRACE IN 1895,1907,1940
PEAK GUST 69e MPH S IN 1976
 
RECORDS FOR OCTOBER 22
HIGH 85 IN 1979
LOW 22 IN 1940
PRECIP 1.37 INCHES IN 1898
SNOWFALL TRACE IN 1969
PEAK GUST 67 MPH ESE IN 1988
 
TODAY'S REPORT PREPARED BY: Robert Skilling