BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, APRIL 18, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
Today's observations:
 
7 A.M.   
Weather: Low overcast, very light drizzle and fog  
Temperature: 37F, Dew point: 37F, Wind: N at 20G33 kts
Wind: Peak wind 33 kts N at 53 past the hour 
Sea-level pressure: 29.73 ins. Hg, rising
Visibility: 8 miles  
6-hour min. 36 deg. 
24-hour rainfall: 0.70 in.
24-hour snowfall: trace   
BHO SA 1155 E8 OVC 8L- 069/37/37/0120G33/973/ PCPN VRY LGT 
PK WND 0133/53/ 8/7// 51016 ASOS 60008 MANUAL 600X/ 
ASOS 70064 MANUAL 70070 10037 20036
 
10 A.M.
Weather: Low overcast, light rain and fog   
Temperature: 38F, Dew point: 38F, Wind: N at 18G30 kts
Wind: Peak wind N @ 32 kts at 17 past the hour
Wind: Variable in direction NW to NE 
Sea-level pressure: 29.80 inches Hg, rising 
Visibility: 2 miles, variable 1-2 miles
BHO SA 1455 E6 OVC 2VR-F 092/38/38/0118G30/980/ VSBY 1V2 
PK WND 0132/17 WND 31V05/ 8/7// 51023 MANUAL 600X ASOS 60008
 
1 P.M.
Weather: Low overcast, light drizzle and fog 
Temperature: 39F, Dew point: 37F, Wind: NNE at 22G30 kts
Wind: Peak wind N @ 30 kts at 44 past the hour
Wind: Variable in direction NW to ENE
Sea-level pressure: 29.82 inches Hg, rising
Visibility: 8 miles
6-hourly rainfall: 0.11 inch
6-hourly min. temp. 37 deg.   
BHO SA 1755 E11 BKN 18 OVC 8L- 098/39/37/0222G30/982/
THN F PCPN VRY LGT PK WND 0130/44 WND 32V06/ 8/72/ 53006
ASOS 60014 MANUAL 6011/ 10039 20037
 
 
WEATHER SUMMARY FOR TUESDAY, APRIL 17
 
TEMPERATURE (DEGREES F)
MAX.....40    NORMAL.....56 
MIN.....35    NORMAL.....38
MEAN....38    NORMAL.....47
 
DEPARTURE FROM 30-YEAR NORMAL...........-9
TOTAL DEPARTURE FOR THE MONTH.........-103 (-6.3 DEGREES/DAY) 
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY..........27   DEPARTURE.........+9
TOTAL HEATING UNITS FOR THE MONTH.........459   DEPARTURE.......+103 
TOTAL HEATING UNITS FOR THE SEASON.......5453   DEPARTURE.......-368
TOTAL HEATING UNITS LAST SEASON TO DATE..5214   DIFFERENCE......+239
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............54 NNE AT  9:32 P.M.   
                   AEROVANE.............53 NNE AT 10:18 P.M.  
                   ASOS.................47 N   AT  9:55 P.M.  
                   DAVIS................50 N   AT  9:32 P.M. 
FASTEST MILE FOR YESTERDAY..............34 NNE AT 10:02 P.M. *     
MAXIMUM 2-MINUTE ASOS AVERAGE...........33 NNE AT 10:03 P.M.   
MAXIMUM 2-MINUTE DAVIS AVERAGE..........33 N   AT  8:54 P.M.  
AVERAGE WIND SPEED AND DIRECTION......  21.7 N 
                    ASOS................20.9   
                    DAVIS...............20.2 N [003 deg]
* last of several occurrences..
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.70  DEPARTURE.....+0.56
                         ASOS..............0.64
TOTAL PRECIPITATION FOR THE MONTH..........6.91  DEPARTURE.....+4.37  
                         ASOS..............6.58    
TOTAL PRECIPITATION FOR THE YEAR..........18.65  DEPARTURE.....+2.48
                         ASOS.............18.22   
 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M........trace  DEPARTURE......-0.1
TOTAL SNOWFALL FOR THE MONTH................0.2  DEPARTURE......-1.6 
TOTAL SNOWFALL FOR THE SEASON..............27.6  DEPARTURE.....-31.1  
    
PRELIMINARY CLIMATE SUMMARY FOR APRIL 2007......CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
 
AERO: Aerovane recording wind system when significant
TSTM: Thunderstorm day
....: Data not yet available
 
4/1  59/33/46/+5/0.42/0/511/67       30 S
4/2  39/35/37/-5/0.33/0/000/00       27 E
4/3  41/32/37/-5/0.04/0/000/00       28 ENE
4/4  36/32/34/-8/0.90/0.2/000/00     38 E
4/5  43/26/35/-8/0.21/T/163/21       36 WSW
4/6  39/23/31/-12/0/0/590/76         36 WSW
4/7  40/26/33/-10/0/0/405/52         35 W
4/8  40/25/33/-11/0/0/619/79         44 W      Aero 42 MPH W
4/9  50/30/40/-4/0/0/746/95          36 W
4/10 43/30/37/-7/0/0/158/20          28 W 
4/11 51/28/40/-5/0/0/.../..          22 SSE
4/12 39/32/36/-9/0.89/T/000/00       42 E      Aero 40 MPH E
4/13 47/31/39/-6/0/0/.../..          41 W      Aero 42 MPH W
4/14 52/35/44/-2/0/0/.../..          37 W
4/15 44/35/40/-6/1.75/T/000/00       66 E      Aero 64 MPH E  
4/16 50/40/45/-1/1.56/0/000/00       73 E      Aero 73 MPH E 
4/17 40/35/38/-9/.../T/000/00        54 NNE
 
4/18 morning low temp. 36 deg; normal now 38 deg.
 
NEW DAILY RECORDS FOR APRIL SO FAR....
 
4/15 - NEW RECORD HIGH PEAK WIND GUST FOR THIS DATE OF 66 MPH E; the previous   
record was 59 mph estimated from the S in 1946 and measured from the S in 1980.   
NEW RECORD DAILY RAINFALL OF 1.75 INS.; previous record 1.29 ins. in 1990.
 
4/16 - NEW RECORD HIGH PEAK WIND GUST OF 73 MPH E; the previous record for this  
 
date was 63 mph SSE in 1996.       
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR APRIL 18
HIGH 92 IN 1976
LOW 23 1887
PRECIP 1.48 IN 1954
SNOWFALL 3.7 IN. IN 1965
PEAK GUST 59 MPH S IN 1982
 
RECORDS FOR APRIL 19
HIGH 94 IN 1976 [RECORD FOR MONTH]
LOW 21 IN 1890
PRECIP 1.71 IN 1969
SNOWFALL 6.0 IN. IN 1887
PEAK GUST 66 MPH E IN 1984
 
TODAY'S REPORT By: Stephanie Radner