BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, APRIL 2, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME VERY LOW WIND SPEEDS TODAY The peak gust so far today was 17 kts (20 MPH) which occurred very early this morning. We have had very low wind speeds for most of the day, beginning around 3:00 AM EDT. The average wind speed since 8:00 AM EDT has been only 0.6 MPH, as recorded by the Merlin wind instrument. The peak gust recorded by Merlin was just 6MPH (since 8:00AM), and the peak gust since 3:00 AM EDT on the 420C gust recorder was only 9 kts (10 MPH). THE MARCH 2009 STATS Temps. Deg. F Av. Max. 44.5 Av. Min. 27.5 Mean 36.0 [-0.3] 24-hour corr. mean 35.2 Max. temp: 60/7th Min. temp: 6/4th Total heating units: 891 [-3] Seasonal total: 5418 [-46] Total precip. 3.55 ins. [-1.24] Greatest in 24 hours: 1.41 ins. [1st-2nd] Total snowfall: 13.4 ins. [+1.9] Greatest in 24 hours: not currently available Sunshine [astronomical]: 210.7 hours or 57% Sunshine [uncorrected]: 203.6 hours or 57% Av. wind speed [uncorrected]: 12.9 MPH Av. wind speed [corrected]: 13.2 MPH Prevailing direction: WNW @ 13% Peak gust: 51 MPH W on the 11th Aerovane: 52 MPH W on the 11th Thunderstorm days: 1 3RD SUNNIEST JANUARY THRU MARCH The combined sunshine total for the first three months of 2009 is the third greatest on our entire record. All three months have had well above average sunshine with an average of 59% of the possible. The combined total hours for the sunniest first three months of any year on record are: (uncorrected card minutes) 1. 559.7 in 1978 2. 548.4 in 1964 3. 548.2 in 2009 Today's Observations: 7 A.M. Weather: Partial obscurement with fog, overcast stratus Temperature: 42F, Dew point: 42F, Wind: SSW at 2 kts (estimated) Wind: Light and variable Sea-level pressure: 30.11 inches Hg, rising Visibility: 1/16 mile, fog 6-hour minimum temperature: 40F 6-hour precipitation: 0.01 inch 24-hour precipitation: 0.14 inch BHO SA 1155 –X E5 OVC 1/16F 198/42/42/E2102/011/ F2 VSBY BRFLY 1 NW OCNL THN SPT IOVC NW WND LGT AND VRB/ 8/6// 53010 MANUAL 6001/ ASOS 60002 MANUAL 70014 ASOS 70013 10045 20040 10 A.M. Weather: Overcast stratus Temperature: 48F, Dew point: 48F, Wind: NW at 2 kts (estimated) Wind: Light and variable Sea-level pressure: 30.10 inches Hg, falling Visibility: 1 mile, 1/2 mile N-E, 1 mile E-S, 2 miles SW-NW, fog BHO SA 1455 E4 OVC 1F 193/48/48/E3202/010/ VSBY N-E 1/2 E-S 1 SW-NW 2 WND LGT AND VRB/ 8/6// 58005 1 P.M. Weather: Overcast stratus Temperature: 52F, Dew point: 48F, Wind: E at 4 kts, Wind: Light and variable Sea-level pressure: 30.06 inches Hg, falling Visibility: 5 miles, fog 6-hour maximum temperature: 52F BHO SA 1755 E18 OVC 5F 180/52/48/1004/006/ WND LGT AND VRB/ 8/6// 58013 10052 20042 WEATHER SUMMARY FOR WEDNESDAY, APRIL 1, 2009 TEMPERATURE (DEGREES F) MAX.....45 NORMAL.....50 MIN.....31 NORMAL.....33 MEAN....38 NORMAL.....41 DEPARTURE FROM 30-YEAR NORMAL..................-3 TOTAL DEPARTURE FOR THE MONTH..................-3 HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............27 DEPARTURE.........+3 TOTAL HEATING UNITS FOR THE MONTH.............27 DEPARTURE.........+3 TOTAL HEATING UNITS FOR THE SEASON..........5445 DEPARTURE........-43 TOTAL HEATING UNITS LAST SEASON TO DATE.....5147 DIFFERENCE......+298 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............24 SE AT 9:13 P.M. AEROVANE.............22 SE AT 9:13 P.M. ASOS.................21 ESE AT 1:06 P.M. DAVIS................23 ESE AT 9:32 P.M. FASTEST MILE FOR YESTERDAY..............17 SE AT 9:13 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........15 SSE AT 9:13 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........18 ESE AT 9:13 P.M. AVERAGE.............9.1 SE ASOS................8.6 DAVIS...............8.9 SE [134 DEGREES] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.14 DEPARTURE.........-0.01 ASOS...............0.13 TOTAL PRECIPITATION FOR THE MONTH...........0.14 DEPARTURE.........-0.01 ASOS...............0.13 TOTAL PRECIPITATION FOR THE YEAR...........10.22 DEPARTURE.........-3.56 ASOS..............11.26 # # 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.........-0.2 TOTAL SNOWFALL FOR THE MONTH................0.0 DEPARTURE.........-0.2 TOTAL SNOWFALL FOR THE SEASON..............78.7 DEPARTURE........+21.6 PRELIMINARY CLIMATE SUMMARY FOR MARCH-APRIL 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 47/28/38/0/+1/671/93 21 SSW 3/18 59/31/45/+8/0/0/448/62 37 SSW AERO 40 MPH S 3/19 45/36/41/+4/0.04/0/000/00 22 S 3/20 36/25/31/-7/0/0/650/89 26 NNE 3/21 43/23/33/-5/0/0/704/96 21 S 3/22 50/27/39/+1/0/0/206/28 29 NW AERO 31 MPH WNW 3/23 32/18/25/-13/0/0/694/94 38 NW 3/24 44/18/31/-8/0/0/630/85 33 NW AERO 37 MPH NW 3/25 49/29/39/0/0/0/670/90 25 N 3/26 53/33/43/+4/0.25/0/298/40 23 SE 3/27 57/36/47/+7/0.10/0/353/47 22 S 3/28 58/39/49/+9/0/0/459/61 22 S 3/29 42/37/40/0/0.57/0/000/00 38 NE TSTM 3/30 42/36/39/-2/0.18/0/000/00 40 WNW 3/31 51/35/43/+2/0/0/738/97 30 W 4/1 43/31/38/-3/0.13/0/.../.. 24 SE AERO 22 MPH SE 4/2 morning low temp: 40F; our normal low is now 33F 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 APRIL 2 HIGH 77 IN 1967 LOW 14 IN 1919 PRECIP 1.83 IN. IN 1970 SNOWFALL 13.0 IN. IN 1887 PEAK GUST 76 MPH SSW IN 1970 RECORDS FOR APRIL 3 HIGH 76 IN 1892 LOW 16 IN 1894 PRECIP 2.18 IN. IN 1990 SNOWFALL 8.0 IN. IN 1915 PEAK GUST 83e MPH NW IN 1977 [RECORD FOR MONTH] TODAY'S REPORT PREPARED BY: Stephanie Radner