BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
  
DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, MAY 9, 2009  
ALL TIMES ARE IN EASTERN STANDARD TIME

MOSTLY CLOUDY WITH A FEW SHOWERS TODAY...
On and off light showers since early this morning have
brought a total of 0.01 inch of rainfall, with just a 
trace since sunrise.  The clouds are lifting as of early
afternoon, and there may some sun during the afternoon. 
May continues on the warm side with the temperature 
reaching the low 70s by 2 PM EDT. The month is now
averaging more than three degrees above normal to date. 

FROM THE RECORD BOOKS...32 YEARS AGO TODAY...
A very late season snow and ice storm brought a total
of 7.8 inches of heavy, wet snow to Blue Hill and mostly 
ice with many power outages to the surrounding area over 
a two-day period on May 9-10, 1977. The total precipitation
was over 3 inches on those days. This was the second latest
measureable snowfall on record with the latest being
1.0 inch that occurred on May 11, 1907. 

Today's observations:

7 A.M.   
Weather: Scattered stratocumulus and altocumulus, overcast
altocumulus, few breaks in overcast, few stratus fractus,
thin fog
Temperature: 57F, Dew point: 56F, Wind: SSE at 8 kts  
Sea-level pressure: 29.74 inches Hg, falling
Visibility: 7 miles, visibility N 10 miles
6-hour minimum temp: 55F
24-hour precipitation: 0.01 ins. 
BHO SA 1155 5 SCT 80 SCT E100 OVC 7 071/57/56/1608/974/ 
FEW BINOVC OVHD FEW LWR STRA THN F VSBY N 10 WND LGT/ 
8/57/ 57010 6001/ 70001 10061 20055

10 A.M.   
Weather: Scattered stratocumulus, broken altocumulus,
overcast altocumulus, few breaks in overcast, higher
clouds visible, few stratus fractus E-SW, hazy
Temperature: 62F, Dew point: 58F, Wind: S at 8 kts 
Wind: Light
Sea-level pressure: 29.70 inches Hg, falling
Visibility: 15 miles, hazy, visibility E-SW 10, WNW 20 miles
BHO SA 1455 5 SCT E80 BKN 100 OVC 15 056/62/58/1708/970/ 
FEW BINOVC OVHD HIR CLDS VSBL FEW STFRA E-SW VSBY E-SW 10 
WNW 20 HAZY WND LGT/ 8/671 58015 6000/

1 P.M.   
Weather: Broken stratocumulus, overcast altocumulus, few
breaks in overcast overhead, sun occasionally visible, hazy
Temperature: 70F, Dew point: 60F, Wind: S at 10 kts
Sea-level pressure: 29.63 inches Hg, falling 
Visibility: 20 miles, hazy  
6-hour maximum temp: 71F   
BHO SA 1755 E25 BKN 70 OVC 20 033/70/60/1810/963/ FEW BINOVC 
OVHD SUN OCNL DMLY VSBL HAZY WND 15V21 PK GST 23 KTS PST HR/ 
8/57/ 56023 6000/ 10071 20057

WEATHER SUMMARY FOR FRIDAY, MAY 8

TEMPERATURE (DEGREES F)
MAX.....75    NORMAL.....64
MIN.....52    NORMAL.....44
MEAN....64    NORMAL.....54

DEPARTURE FROM 30-YEAR NORMAL..........+10
TOTAL DEPARTURE FOR THE MONTH..........+30 [+3.6 DEGREES/DAY] 

HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY.............1  DEPARTURE......-10
TOTAL HEATING UNITS FOR THE MONTH............65  DEPARTURE......-32
TOTAL HEATING UNITS FOR THE SEASON.........5961  DEPARTURE.....-162
TOTAL HEATING UNITS LAST SEASON TO DATE....5708  DIFFERENCE....+253

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............28 S   AT  1:45 P.M. 
                   AEROVANE.............25 S   AT  1:45 P.M. 
                   ASOS.................25 SSW AT  1:46 P.M. 
                   DAVIS................28 S   AT  1:45 P.M.
FASTEST MILE FOR YESTERDAY..............20 S   AT  1:45 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE...........20 SSW AT  1:46 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..........21 SSW AT  1:28 P.M.
AVERAGE WIND SPEED AND DIRECTION......10.9 SW
                   ASOS................9.7 
                   DAVIS...............9.9 SW [221 DEG]
* last of several occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.01  DEPARTURE....-0.11
                         ASOS..............0.01 
TOTAL PRECIPITATION FOR THE MONTH..........2.02  DEPARTURE....+1.01
                         ASOS..............2.01  
TOTAL PRECIPITATION FOR THE YEAR..........16.63  DEPARTURE....-2.33
                         ASOS.............17.69   

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE..... 0.0
TOTAL SNOWFALL FOR THE MONTH................0.0  DEPARTURE.....-0.1
TOTAL SNOWFALL FOR THE SEASON..............78.9  DEPARTURE.....18.8  
 
PRELIMINARY CLIMATE SUMMARY FOR MAY 2009 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane recording wind system gust when significant
TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized

5/1 64/53/59/+7/T/000/00          37 SSW   AERO 37 MPH SSW
5/2 68/52/60/+8/0.05/263/31       32 WNW 
5/3 64/48/56/+3/T/068/08          25 S 
5/4 64/48/56/+3/0.01/009/01       17 SSW 
5/5 52/44/48/-5/.../000/00        43 NNE   AERO 40 MPH NNE
5/6 63/43/53/-1/.../189/22        24 SSE   
5/7 68/49/59/+5/.../009/01        29 S     
5/8 75/52/64/+10/.../.../..       28 S

5/9 morning low temp: 55F; our normal low is now 45F 

NEW DAILY RECORDS FOR MAY 2009...
NONE

DAILY EXTREMES

Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):

RECORDS FOR MAY 9
HIGH 93F IN 2000
LOW 31F IN 1947
PRECIP 2.72 INCHES IN 1954
SNOWFALL 5.0 INS IN 1977 (RECORD FOR MAY)
PEAK GUST 70e MPH NE IN 1977

RECORDS FOR MAY 10
HIGH 93F IN 1896
LOW 29F IN 1900
PRE 1.85 INS IN 1998
SNOW 2.8 INS 1977 (7.8 INS TOTAL 5/9-5/10 1977)
PEAK GUST 64 MPH S IN 1990

TODAY'S REPORT PREPARED BY: Mike Iacono