BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, APRIL 23, 2007   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
RECORD OF 85 DEGREES FOR TODAY SET IN 1908 EQUALED BY 2 P.M.
 
VERY SUNNY WARM APRIL WEATHER CONTINUES TODAY
WITH TEMPERATURES HEADED INTO THE 80'S  
THE AIR CONTINUES VERY DRY WITH DEW POINTS IN MID-30'S
LIGHT HAZE INCREASING..VISIBILITY DOWN TO 35-40 MILES 
MT WACHUSETT SEEN VERY FAINTLY 
 
Today will mark the 4th consecutive day with very sunny 
and dry weather. Yesterday marked the 3rd consecutive day with 
our sunshine between 90 and 100% of possible. When the temp-
erature reached 80 degrees it will be the first time since 
last September 18th with a maximum of 80 degrees.   
Today's record high temperature is 85 degrees in 1908.  
Early this afternoon the high temperature had reached 85 
degrees tying that record. 
 
The National Weather Service has issued a red flag warning  
today for very high outdoor fire danger as southwest winds
are expected to become gusty this afternoon with relative 
humidities between 15 and 20%.  
 
Today's observations:
 
7 A.M.   
Weather: Clear, light haze 
Temperature: 57F, Dew point: 34F, Wind: SSW at 13 kts
Sea-level pressure: 30.09 ins. Hg, steady
Visibility: 40 miles, 45 WNW 
6-hour min. 49 deg.   
BHO SA 1155 CLR 40 188/57/34/2113/009/ VSBY WNW 45 LGT HZ/ 
58001 10057 20049 
 
10 A.M.
Weather: Clear, light haze   
Temperature: 77F, Dew point: 35F, Wind: SSW at 10 kts
Sea-level pressure: 30.05 inches Hg, falling 
Visibility: 35 miles, light haze  
BHO SA 1455 CLR 35 175/77/35/2110/005/ LGT HZ WND 18V25/ 
58013
 
1 P.M.
Weather: Clear, few cirrus WSW-N, light haze 
Temperature: 84F, Dew point: 38F, Wind: S at 15G23 kts
Sea-level pressure: 29.94 inches Hg, falling 
Visibility: 35 miles, 45 miles WNW, light haze   
6-hourly max. temp. 85 deg. 
BHO SA 1755 CLR 35 139/84/38/1915G23/994/ CI DSNT WSW-N 
VSBY WNW 45 LGT HZ ALQDS PK WND 1826/05/ WND 15V21/ 
8/001 58036 10085 20057
 
WEATHER SUMMARY FOR SUNDAY, APRIL 22
 
TEMPERATURE (DEGREES F)
MAX.....75    NORMAL.....58 
MIN.....50    NORMAL.....39
MEAN....63    NORMAL.....49
 
DEPARTURE FROM 30-YEAR NORMAL..........+14
TOTAL DEPARTURE FOR THE MONTH..........-91 (-4.3 DEGREES/DAY) 
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY.......... 2   DEPARTURE........-12
TOTAL HEATING UNITS FOR THE MONTH.........533   DEPARTURE.......+ 90 
TOTAL HEATING UNITS FOR THE SEASON.......5527   DEPARTURE.......-380
TOTAL HEATING UNITS LAST SEASON TO DATE..5282   DIFFERENCE......+245
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............31 SSE AT 6:37 P.M.    
                   AEROVANE.............30 SSE AT 6:37 P.M.   
                   ASOS.................28 S   AT 9:57 P.M.   
                   DAVIS................32 S   AT 6:37 P.M.   
FASTEST MILE FOR YESTERDAY..............22 SSE AT 6:35 P.M. * 
MAXIMUM 2-MINUTE ASOS AVERAGE...........23 SSE AT 6:37 P.M.      
MAXIMUM 2-MINUTE DAVIS AVERAGE..........23 SSE AT 6:37 P.M.     
AVERAGE WIND SPEED AND DIRECTION........11.6 N  
                    ASOS................12.1    
                    DAVIS...............10.5 ESE [110 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 THE MONTH..........7.18  DEPARTURE.....+3.94  
                         ASOS..............6.85    
TOTAL PRECIPITATION FOR THE YEAR..........18.92  DEPARTURE.....+2.05
                         ASOS.............18.49   
 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE......-0.1
TOTAL SNOWFALL FOR THE MONTH................0.2  DEPARTURE......-2.1 
TOTAL SNOWFALL FOR THE SEASON..............27.6  DEPARTURE.....-31.6  
    
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/-5/0/0/712/90          22 SSE
4/12 39/32/36/-9/0.89/T/000/00       42 E      Aero 40 MPH E
4/13 47/31/39/-6/0/0/096/12          41 W      Aero 42 MPH W
4/14 52/35/44/-2/0/0/392/49          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/-9/0.69/T/000/00       54 NNE    Aero 53 MPH NNE
4/18 39/36/38/-9/0.37/0/000/00       43 N
4/19 49/36/43/-4/0.02/T/285/35       38 NE     Aero 35 MPH NE 
4/20 57/36/47/-1/0/0/815/100         31 N
4/21 74/45/60/+12/0/0/753/92         24 NW
4/22 75/50/63/+14/0/0/779/95         31 SSE
 
4/23 morning low temp. 49 deg. normal now 39 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.       
 
4/23 - * EQUALLED RECORD HIGH MAXIMUM TEMPERATURE OF 85 DEGREES set in 1908.
* as of 2 p.m. 4/23
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR APRIL 23
HIGH 85 IN 1908
LOW 25 IN 1933,1989
PRECIP 1.51 IN. IN 1998
SNOWFALL 0.5 IN. IN 1911, 1956
PEAK GUST 64 MPH WNW IN 1962
 
RECORDS FOR APRIL 24
HIGH 82 IN 2001
LOW 22 IN 1930
PRECIP 2.51 INS IN 1898
SNOWFALL 1.2 INS IN 1967
PEAK GUST 59 MPH NW IN 1962
 
TODAY'S REPORT By: Robert Skilling  
 
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