BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, MARCH 17, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME VERY SUNNY TODAY AFTER A COMPLETELY CLOUDY DAY YESTERDAY MARCH SUNSHINE IS ABOVE THE AVERAGE High clouds cleared away early this morning leaving us with another very sunny day, one of seven this month. The monthly sunshine is running around 7 points above normal so far. A light to gentle northeast wind is holding temperatures close to the normals while monthly temperature and precipitation are both running near average. Today's observations: 7 A.M. Weather: Scattered high cirrus clouds, layer of cirrus and some dense cirrus from NNW-E-S, patch of altocumulus, lenticular northwest, few cirrocumulus northwest thin fog below inversion few dense patches northeast. Temperature: 32F, Dew point: 27F, Wind: NE at 4 kts, Sea-level pressure: 30.33 inches Hg, rising Visibility: 15 miles, except 25 miles over inversion WNW 6-hour minimum temperature: 28F BHO SA 1155 250 SCT 15 271/32/27/0404/033/ SKY CLRG PST HR PTCH ACSL NNW CI/DENS CI LYR NNW-NE-SW FEW CC NW FEW PTCHS DENS FG BLO INVSN NE THN F BLO INVSN ALQDS VSBY 25 ABV INVSN WNW/ 8/042 58001 10032 20028 10 A.M. Weather: Clear, cirrus distant NNW-E-S Temperature: 40F, Dew point: 24F, Wind: SSW at 2 kts, Wind: light and variable Sea-level pressure: 30.34 inches Hg, falling Visibility: 35 miles, 45 miles NE, thin smoke W-NW BHO SA 1455 CLR 35 274/40/24/E2102/034/ CI DSNT NNW-E-S THN K W-NW VSBY NE 45 WND L/V/ 8/001 50003 1 P.M. Weather: Clear Temperature: 44F, Dew point: 28F, Wind: NNE at 6 kts, Sea-level pressure: 30.31 inches Hg, falling Visibility: 45 miles, thin smoke aloft NW-N 6-hour maximum temperature: 45F BHO SA 1755 CLR 45 263/44/28/0306/031/ THN K LYR ALF NW-N/ 58011 10045 20032 WEATHER SUMMARY FOR MONDAY, MARCH 16, 2009 TEMPERATURE (DEGREES F) MAX.....42 NORMAL.....45 MIN.....29 NORMAL.....28 MEAN....36 NORMAL.....36 DEPARTURE FROM 30-YEAR NORMAL................. 0 TOTAL DEPARTURE FOR THE MONTH.................- 2 [-0.3 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............29 DEPARTURE..........0 TOTAL HEATING UNITS FOR THE MONTH............499 DEPARTURE..........0 TOTAL HEATING UNITS FOR THE SEASON..........5026 DEPARTURE........-43 TOTAL HEATING UNITS LAST SEASON TO DATE.....4701 DIFFERENCE......+325 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............30 NE AT 5:19 A.M. AEROVANE.............28 NE AT 5:12 A.M. ASOS.................30 NE AT 5:30 A.M. DAVIS................33 NNE AT 5:24 A.M. FASTEST MILE FOR YESTERDAY..............23 NE AT 5:11 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........23 NNE AT 3:22 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........24 NE AT 5:11 A.M. AVERAGE............11.0 NE ASOS...............10.7 DAVIS..............11.5 NE [040 DEGREES] 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...........2.41 DEPARTURE.........-0.02 ASOS...............2.34 TOTAL PRECIPITATION FOR THE YEAR............8.94 DEPARTURE.........-2.33 ASOS...............9.96 # # Includes erroneous ASOS precipitation data on 1/1/09, 1/2/09 and 2/27/09. SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0 DEPARTURE.........-0.4 TOTAL SNOWFALL FOR THE MONTH...............13.4 DEPARTURE.........+6.4 TOTAL SNOWFALL FOR THE SEASON..............78.7 DEPARTURE........+26.3 PRELIMINARY CLIMATE SUMMARY FOR MARCH 2009 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/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 3/1 28/21/25/-7/0.26/1.9/000/00 38 NNE 3/2 22/15/19/-13/1.21/8.2/000/00 40 NNE AERO 37 MPH NNE 3/3 25/11/18/-14/0.01/0.1/640/94 33 NW 3/4 30/6/18/-14/0/0/684/100 31 WNW 3/5 39/16/28/-5/0/0/659/96 25 WSW 3/6 49/30/40/+7/T/0/152/22 43 S AERO 41 MPH S 3/7 60/42/51/+18/0.06/0/429/62 37 S 3/8 57/42/50/+16/0/0/445/64 39 WNW AERO 40 MPH WNW 3/9 42/28/35/+1/0.72/3.2/000/00 33 N 3/10 42/26/34/0/0.02/0/470/67 23 SSE 3/11 50/33/42/+7/0.13/0/000/00 51 W 3/12 39/25/32/-3/0/0/685/97 44 W AERO 45 MPH W 3/13 37/19/28/-7/0/0/660/93 26 SSE 3/14 50/25/38/+2/0/0/613/86 24 SSW 3/15 59/34/47/+11/0/0/686/96 17 SSW 3/16 42/29/36/0/0/0/000/00 30 NE 3/17 morning low temp: 28F; our normal low is now 28F NEW DAILY RECORDS FOR MARCH 2009... 3/2: DAILY SNOWFALL 8.2 INS. SURPASSES PREVIOUS RECORD OF 7.1 INS. IN 1948 3/7: DAILY MINIMUM 42 TIES RECORD HIGH MINIMUM FOR DATE PREVIOUSLY SET IN 1974 AND 1987 3/8: DAILY MINIMUM 42 TIES RECORD HIGH MINIMUM FOR DATE PREVIOUSLY SET IN 1995 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR MARCH 17 HIGH 69 IN 2003 LOW 6 IN 1885 PRECIP 1.97 INS. IN 1968 SNOWFALL 6.5 INS. IN 1956 PEAK GUST 70 MPH SSW IN 1973 RECORDS FOR MARCH 18 HIGH 68 IN 1999 LOW 0 IN 1885 PRECIP 5.61 INS. IN 1968 [RECORD FOR MONTH] SNOWFALL 9.3 INS. IN 1985 PEAK GUST 71e MPH WNW IN 1941 TODAY'S REPORT PREPARED BY: Robert Skilling