BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY MONDAY, MARCH 30, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME THUNDERSTORM PASSED TO OUR NORTHWEST SUNDAY P.M. WIND SQUALL INCLUDES GUST TO WSW 37 MPH LATE EVENING RAINFALL TOTALS 0.57 INCH SINCE EARLY SUNDAY The first thunderstorm of the year to date passed to the west and northwest of here yesterday during the afternoon generally between 4 and 5 p.m. A lightning strike was reported on a home in Dover. Another line of decaying thunderstorms moved by during the hour before midnight EDT. No thunder was reported here but there was 0.02 rainfall in a shower. A pressure jump of 0.06 in a few minutes was recorded between 11:32 and 11:35 P.M. EDT. A wind shift from NNE to WSW preceded a wind squall with peak gusts to 37 MPH WSW and a sustained speed of 30 MPH (fastest mile) WSW at 11:35 p.m. EDT. Total rainfall during a period of rainfall which began early Sunday morning and ended by midnight last night was 0.57 inch. Today's observations: 7 A.M. Weather: Low overcast with stratus, stratus drifting over and below summit Temperature: 39F, Dew point: 39F, Wind: W at 8 kts Sea-level pressure: 29.39 inches Hg, rising Visibility: 4 miles in fog, S 3 miles, NE 8 miles, visibility increased rapidly past hour 6-hour minimum temperature: 37F 24-hour precipitation: 0.49 inch BHO SA 1155 E6 OVC 4F 954/39/39/2808/939/ STRA DRFTG OVR/BLO SMT VSBY S 3 NE 8 VSBY INCRSD RPDLY PST HR/ 8/6// 53018 ASOS 70053 MANUAL 70049 10039 20037 10 A.M. Weather: Scattered stratus fractus, overcast nimbostratus, very light rain showers occurring Temperature: 41F, Dew point: 40F, Wind: W at 19G27 kts, Wind: Peak wind 27 kts W at 9:54 A.M., Wind: direction variability WSW-WNW Sea-level pressure: 29.41 inches Hg, rising Visibility: 25 miles, north 15 miles, east 20 miles, and southeast 30 miles 3-hourly rainfall: 0.01 inch BHO SA 1455 12 SCT E45 OVC 25RW- 958/41/40/2819G27/941/ VSBY N 15 E 20 SE 30 PK WND 2827/54/ WND 24V30 RBUKN PCPN VRY LGT/ 8/72/ 52004 MANUAL 6001/ ASOS 60001 1 P.M. Weather: Overcast stratus fractus with higher nimbostratus layer occasionally visible, light rain occurring Temperature: 39F, Dew point: 39F, Wind: W at 18G29 kts Wind: Peak wind gust 35 kts WNW at 12:29 P.M., Wind: direction variable WSW-NW Sea-level pressure: 29.47 inches Hg, rising Visibility: 6 miles in light rain/fog, southwest 8 miles 6-hour maximum temperature: 42F 6-hour precipitation: 0.12 inches BHO SA 1755 E12 OVC 6R-F 981/39/39/2818G29/947/ CIG RGD HIER OVC NS OCNL VSB VSBY SW 8 PK WND 2935/29/ WND 25V31/ 8/72/ 51023 ASOS 60011 MANUAL 6012/ 10042 20039 WEATHER SUMMARY FOR SUNDAY, MARCH 29, 2009 TEMPERATURE (DEGREES F) MAX.....42 NORMAL.....49 MIN.....37 NORMAL.....32 MEAN....40 NORMAL.....40 DEPARTURE FROM 30-YEAR NORMAL.................. 0 TOTAL DEPARTURE FOR THE MONTH..................-1 [-0.2 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............25 DEPARTURE......... 0 TOTAL HEATING UNITS FOR THE MONTH............843 DEPARTURE.........-3 TOTAL HEATING UNITS FOR THE SEASON..........5370 DEPARTURE........-46 * TOTAL HEATING UNITS LAST SEASON TO DATE.....5077 DIFFERENCE......+293 * seasonal dep. is corrected, was reported at -36 in Sunday's, 3/29, report, should have been -46. PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............38 NE AT 9:28 A.M. AEROVANE.............36 NE AT 9:28 A.M. ASOS.................37 NE AT 9:29 A.M. DAVIS................39 NE AT 9:28 A.M. FASTEST MILE FOR YESTERDAY..............30 WSW AT 10:35 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........29 WSW AT 10:35 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........28 NE AT 9:29 A.M. AVERAGE............12.5 NE ASOS...............11.9 DAVIS..............12.1 NNE [030 DEGREES] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.49 DEPARTURE.........+0.34 ASOS...............0.53 TOTAL PRECIPITATION FOR THE MONTH...........3.37 DEPARTURE.........-1.12 ASOS...............3.33 TOTAL PRECIPITATION FOR THE YEAR............9.90 DEPARTURE.........-3.43 ASOS..............10.95 # # 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...............13.4 DEPARTURE.........+2.3 TOTAL SNOWFALL FOR THE SEASON..............78.7 DEPARTURE........+22.2 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 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 morning low temp: 37F; our normal low is now 32F 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 30 HIGH 83 IN 1977 LOW 10 IN 1887 PRECIP 2.82 INS. IN 2001 SNOWFALL 3.9 INS. IN 1957 PEAK GUST 60 MPH NW IN 1999 RECORDS FOR MARCH 31 HIGH 89 IN 1998 [RECORD HIGH FOR MONTH] LOW 16 IN 1923 PRECIP 2.89 IN 1987 SNOWFALL 15.0 IN 1997 PEAK GUST 81 MPH SSE IN 1987 TODAY'S REPORT PREPARED BY: Robert Skilling