BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA   DAILY DISCUSSION AND CLIMATE SUMMARY WEDNESDAY, MARCH 21, 2007  ALL TIMES ARE IN EASTERN STANDARD TIME   Today's observations:   7 A.M.   Weather: Clear Temperature: 18F, Dew point: 0F, Wind: WNW at 11 kt Sea-level pressure: 30.80 inches Hg, rising Visibility: 70 miles 6-hour min. temp. 16F Snow on ground: 3 inches BHO SA 1155 CLR 70 430/18/00/3011/080/ FEW CI/ 8/001 4/003 51020 10019 20016   10 A.M.   Weather: Clear Temperature: 29F, Dew point: 4F, Wind: E at 06 kt  Sea-level pressure: 30.81 inches Hg, rising Visibility: 70 miles BHO SA 1455 CLR 70 435/29/4/0906/081/ FEW CI WND VRBL/ 8/001 50005   1 P.M.   Weather: Clear Temperature: 33F, Dew point: 12F, Wind: ESE at 07 kt  Sea-level pressure: 30.76 inches Hg, falling Visibility: 70 miles BHO SA 1755 250 –SCT 70 416/33/12/1107/076/ 8/001 58019 10033 20018   WEATHER SUMMARY FOR TUESDAY, MARCH 20   TEMPERATURE (DEGREES F) MAX.....42    NORMAL.....46 MIN.....21    NORMAL.....29 MEAN....32    NORMAL.....38   DEPARTURE FROM 30-YEAR NORMAL...........-6 TOTAL DEPARTURE FOR THE MONTH..........-43 (-2.4 DEGREES/DAY)   HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY..........33   DEPARTURE........+5 TOTAL HEATING UNITS FOR THE MONTH.........651   DEPARTURE.......+39 TOTAL HEATING UNITS FOR THE SEASON.......4742   DEPARTURE......-440 TOTAL HEATING UNITS LAST SEASON TO DATE..4705   DIFFERENCE......+37   PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............46 WSW AT  8:57 A.M.                            AEROVANE.............47 W   AT  2:48 P.M.                          ASOS.................45 WSW AT  8:58 A.M.                          DAVIS................48 WSW AT  8:57 A.M.         FASTEST MILE FOR YESTERDAY..............36 WSW AT  9:43 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........35 WSW AT  9:42 A.M.    MAXIMUM 2-MINUTE DAVIS AVERAGE..........36 WSW AT  9:43 A.M.    AVERAGE WIND SPEED AND DIRECTION........21.6 WNW                     ASOS................19.6                         DAVIS...............21.4 WSW  [256 deg]    PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE.....-0.16                          ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........5.42  DEPARTURE.....+2.20                           ASOS..............5.40    TOTAL PRECIPITATION FOR THE YEAR..........11.14  DEPARTURE.....-0.92                          ASOS.............11.03     SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE......-0.4 TOTAL SNOWFALL FOR THE MONTH................9.9  DEPARTURE......+1.3  TOTAL SNOWFALL FOR THE SEASON..............23.8  DEPARTURE.....-30.2        PRELIMINARY CLIMATE SUMMARY FOR MARCH 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   3/1  40/22/31/-1/0/0/512/76          24 NW   Aero 23 MPH NW 3/2  49/28/39/+7/1.74/0.4/000/00     48 E    Aero 45 MPH E 3/3  58/33/46/+14/0/0/489/72         44 WNW  Aero 43 MPH WNW 3/4  40/26/33/0/0/0/471/69           37 W 3/5  37/19/28/-5/T/T/198/29          58 W    Aero 57 MPH W 3/6  19/3/11/-22/0/0/667/97 *        57 W    Aero 61 MPH W 3/7  22/2/12/-21/0/0/504/73          28 SW    3/8  25/5/15/-19/T/T/471/68          51 WNW  Aero 54 MPH WNW 3/9  34/1/18/-16/0/0/668/96 *        25 S     3/10 49/22/36/+2/0/0/322/46          39 S    Aero 39 MPH S 3/11 51/33/42/+7/0.26/0/513/73       32 W 3/12 55/31/43/+8/0/0/423/60          24 SSW 3/13 60/36/48/+13/0/0/319/45         35 S    Aero 33 MPH S 3/14 66/42/54/+18/0/0/405/57         36 S 3/15 54/35/45/+9/0.07/0/000/00       36 NW 3/16 35/24/30/-6/1.65/8.5/000/00     55 NE   Aero 53 MPH NE 3/17 34/24/29/-6/1.52/T/000/00       51 NNE  Aero 50 MPH NE 3/18 31/20/26/-11/0/0/258/37         43 W    Aero 42 MPH W 3/19 40/22/31/-6/0.18/1.0/442/61     38 S    Aero 37 MPH S 3/20 42/21/32/-6/0/0/677/93          46 WSW  Aero 47 MPH W   3/21 morning low temp. 16 degrees; normal low now 29   * Record low maximum temperature of 19 on the 6th surpasses previous 21 set   in 1916. * Record low minimum temperature of 3 on the 6th ties previous 3 set in 1948. * Record low minimum temperature of 1 on the 9th breaks previous 5 set in   1885, 1943, and 1996.   DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated):   RECORDS FOR MARCH 21 HIGH 81 IN 1921 LOW 2 IN 1885 PRECIP 2.67 INS. IN 1974 SNOWFALL 10.6 INS. IN 1958 PEAK GUST 72 MPH NE IN 1958   RECORDS FOR MARCH 22 HIGH 71 IN 1948 LOW 3 IN 1885 PRECIP 3.48 INS. IN 2001 SNOWFALL 8.7 INS. 1967 WIND 84e MPH E IN 1977   TODAY'S REPORT By: Stephanie Radner