BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, MAY 23, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME FEW LIGHT SHOWERS THIS MORNING...MUCH COOLER TEMPERATURES TODAY... A few light showers between 8:25 AM and 10:50 AM EDT this morning brought just a trace of new precipitation. After a high in the upper 80s yesterday, the temperature has remained in the 50s to low 60s today with a light northeast wind. Today's observations: 7 A.M. Weather: Broken stratocumulus, overcast altocumulus, few breaks in overcast ENE-E Temperature: 57F, Dew point: 43F, Wind: NE at 11G24 kts Sea-level pressure: 30.27 inches Hg, rising Visibility: 70 miles 6-hour minimum temp: 56F 24-hour precipitation: 0.00 inch BHO SA 1155 E65 BKN 100 BKN 150 OVC 70 249/57/43/0411G24/ 027/ FEW LWR SC FEW BINOVC ENE-E/ 8/57/ 53017 10065 20056 10 A.M. Weather: Scattered stratocumulus, overcast altocumulus, higher clouds visible, few breaks in overcast overhead-NW rain showers visible ENE-S moving E, hazy Temperature: 53F, Dew point: 45F, Wind: NE at 9 kts, Sea-level pressure: 30.29 inches Hg, rising Visibility: 40 miles 3-hour precipitation: trace BHO SA 1455 50 SCT E100 OVC 40 257/53/45/0509/029/ HIR CLDS VSBL FEW BINOVC OVHD-NW RW ENE-S MVG E RE50 HAZY/ 8/571 51008 6000/ 1 P.M. Weather: Scattered altocumulus, thin broken cirrus, hazy Temperature: 62F, Dew point: 45F, Wind: NE at 6 kts, Wind: Light and variable Sea-level pressure: 30.26 inches Hg, falling Visibility: 50 miles 6-hour maximum temp: 62F 6-hour precipitation: trace BHO SA 1755 70 SCT 180 SCT 250 –BKN 50 246/62/45/0506/026/ HAZY WND LGT AND VRB/ 8/031 58011 6000/ 10062 20052 WEATHER SUMMARY FOR FRIDAY, MAY 22 TEMPERATURE (DEGREES F) MAX.....87 NORMAL.....69 MIN.....59 NORMAL.....49 MEAN....73 NORMAL.....59 DEPARTURE FROM 30-YEAR NORMAL..........+14 TOTAL DEPARTURE FOR THE MONTH..........+69 [+2.9 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............0 DEPARTURE.......-7 TOTAL HEATING UNITS FOR THE MONTH...........157 DEPARTURE......-62 TOTAL HEATING UNITS FOR THE SEASON.........6053 DEPARTURE.....-192 TOTAL HEATING UNITS LAST SEASON TO DATE....5869 DIFFERENCE....+184 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............31 N AT 7:55 P.M. AEROVANE..............25 SSW AT 2:04 A.M. ASOS..................28 NNE AT 7:55 P.M. DAVIS.................31 N AT 7:54 P.M. FASTEST MILE FOR YESTERDAY...............21 SSW AT 12:39 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE............21 NNE AT 7:56 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........22 N AT 7:56 P.M. AVERAGE WIND SPEED AND DIRECTION.......12.8 SSW ASOS................11.5 DAVIS...............12.7 SW [225 DEG] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE....-0.12 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........2.38 DEPARTURE....-0.31 ASOS..............2.37 TOTAL PRECIPITATION FOR THE YEAR..........16.99 DEPARTURE....-3.65 ASOS.............18.05 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0 DEPARTURE..... 0.0 TOTAL SNOWFALL FOR THE MONTH................0.0 DEPARTURE.....-0.1 TOTAL SNOWFALL FOR THE SEASON..............78.9 DEPARTURE.....18.8 PRELIMINARY CLIMATE SUMMARY FOR MAY 2009 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/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 5/1 64/53/59/+7/T/000/00 37 SSW AERO 37 MPH SSW 5/2 68/52/60/+8/0.05/263/31 32 WNW 5/3 64/48/56/+3/T/068/08 25 S 5/4 64/48/56/+3/0.01/009/01 17 SSW 5/5 52/44/48/-5/0.95/000/00 43 NNE AERO 40 MPH NNE 5/6 63/43/53/-1/0.40/189/22 24 SSE 5/7 68/49/59/+5/0.60/009/01 29 S 5/8 75/52/64/+10/0/690/80 28 S 5/9 71/55/63/+8/0.14/104/12 31 W TSTM 5/10 65/46/56/+1/0/840/97 53 W Aero 50 MPH W 5/11 63/41/52/-3/0/781/90 24 WNW 5/12 63/45/54/-2/0/696/80 22 ENE 5/13 70/45/58/+2/0/732/84 31 SSE AERO 29 MPH SSE 5/14 62/47/55/-2/0.10/166/19 53 S AERO 52 MPH S 5/15 76/54/65/+8/0/474/54 38 S AERO 38 MPH S 5/16 68/54/61/+4/T/457/52 35 S AERO 35 MPH S 5/17 61/49/55/-2/0.09/009/01 35 WNW AERO 33 MPH WNW 5/18 53/42/48/-10/0.04/168/19 27 NE 5/19 70/42/56/-2/0/813/92 28 S 5/20 82/49/66/+8/0/771/87 31 SSW 5/21 89/59/74/+15/0/870/98 37 S AERO 34 MPH S 5/22 87/59/73/+14/0/.../.. 31 N 5/23 our morning low temp: 52F; the normal low is now 49F NEW DAILY RECORDS FOR MAY 2009... 5/14: RECORD PEAK WIND GUST 53 MPH S; surpasses previous record of 50 MPH SW in 1976 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR MAY 23 HIGH 92F IN 1964,1992 LOW 38F IN 1976 PRECIP 0.97 INS IN 1979 PEAK GUST 49e MPH W IN 1945 RECORDS FOR MAY 24 HIGH 92F IN 1964 LOW 35F IN 1956 PRECIP 2.13 INS IN 1951 PEAK GUST 54 MPH NNE IN 2005 TODAY'S REPORT PREPARED BY: Mike Iacono