BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, MAY 20, 2010 ALL TIMES ARE IN EASTERN STANDARD TIME OVER AN INCH AND A HALF OF RAINFALL FROM NORTHEASTER ENDED AS DRIZZLE LAST EVENING TEMPERATURES WERE RISING RAPIDLY TODAY WITH PLENTY OF BRIGHT SUNSHINE ALONG WITH LIGHT TO GENTLE SOUTHWEST WINDS The rain which fell from the moderate late spring northeaster reached a total of 1.65 inches. Peak wind gusts reached 42 to 46 MPH from the northeast early yesterday morning. Today's bright sunshine and winds from the southwest are allowing temperatures to soar through the 70's after a very cool day with a high temperature of only 52F yesterday. Today's observations: 7 A.M. Weather: Clear, few stratus, stratus and thin fog dissipating past hour, dense cirrus distant NNW-NNE Temperature: 55F, Dew point: 53F, Wind: WSW at 7 kts Sea-level pressure: 29.92 inches Hg, rising Visibility: 50 miles, 75 miles northwest 6-hour minimum temp: 50F 24-hour precip: 0.21 ins. BHO SA 1155 CLR 50 132/55/53/2507/992/ FEW STRA PTCH DNS CI DSNT NNW-NNE STRA/THN FG DSSPTNG PST HR VSBY NW 75/ 8/602 51018 MANUAL 70021 ASOS 70020 10055 20050 10 A.M. Weather: Clear, dense cirrus NNW-NE Temperature: 68F, Dew point: 53F, Wind: SW at 7 kts Wind: Direction variable south to west Sea-level pressure: 29.93 inches Hg, falling Visibility: 70 miles BHO SA 1455 CLR 70 134/68/53/2207/993/ DNS CI DSNT NNW-NE WND 18V27/ 8/002 50002 1 P.M. Weather: Scattered dense cirrus, light distant haze increasing Temperature: 77F, Dew point: 50F, Wind: SSW at 13 kts Wind: Direction variable south to west-southwest Sea-level pressure: 29.91 inches Hg, falling Visibility: 60 miles 6-hourly max. temp: 77F BHO SA 1755 220 SCT 60 128/77/50/2113/991/ PTCHS DNS CI LGT DSNT HZ INCRSNG WND 18V24/ 8/002 56008 10077 20055 WEATHER SUMMARY FOR WEDNESDAY, MAY 19 TEMPERATURE (DEGREES F) MAX.....52 NORMAL.....68 MIN.....45 NORMAL.....48 MEAN....49 NORMAL.....58 DEPARTURE FROM 30-YEAR AVERAGE................-9 TOTAL DEPARTURE FOR THE MONTH................+61 [+3.0 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............16 DEPARTURE........+8 TOTAL HEATING UNITS FOR THE MONTH...........148 DEPARTURE.......-50 TOTAL HEATING UNITS FOR THE SEASON.........5630 DEPARTURE......-594 TOTAL HEATING UNITS LAST SEASON TO DATE....6053 DIFFERENCE.....-423 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............42 NE AT 12:26 A.M. AEROVANE..............45 NE AT 12:26 A.M. ASOS..................46 NE AT 12:27 A.M. DAVIS.................43 NE AT 12:26 A.M. THE FASTEST MILE FOR YESTERDAY...........29 NE AT 1:20 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE............28 NE AT 12:02 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........28 NE AT 12:13 A.M. AVERAGE WIND SPEED AND DIRECTION.......14.5 NE ASOS................12.6 DAVIS...............14.1 NNE [030 DEG] .. PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.21 DEPARTURE......+0.09 ASOS..............0.20 TOTAL PRECIPITATION FOR THE MONTH..........2.48 DEPARTURE......+0.14 ASOS..............2.46 TOTAL PRECIPITATION FOR THE YEAR..........32.84 DEPARTURE.....+12.55 ASOS.............32.91 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..............64.4 DEPARTURE......+4.3 PRELIMINARY CLIMATE SUMMARY FOR MAY 2010 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane wind recording system gust when significant TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 5/1 81/58/70/+18/0.00/0/684/81 29 SE 5/2 87/56/72/+20/0.00/0/432/51 29 SSW 5/3 80/62/71/+18/0.04/0/170/20 41 W AERO 50 MPH W 5/4 81/52/67/+14/0.09/0/562/66 51 WNW AERO 58 MPH WNW TSTM 5/5 78/50/64/+11/0.00/0/845/99 28 S 5/6 76/54/65/+11/T/0/531/62 46 WNW AERO 48 MPH WNW 5/7 72/47/60/+6/0.00/0/798/93 28 W 5/8 63/45/54/0/0.63/0/034/04 39 WSW AERO 39 MPH WSW TSTM 5/9 53/37/45/-10/0.00/0/717/83 46 W AERO 50 MPH W 5/10 57/35/46/-9/0.00/0/831/96 31 WNW AERO 35 MPH WNW 5/11 57/34/46/-9/0.00/0/625/72 22 SSE 5/12 50/41/46/-10/T/0/000/00 22 S 5/13 66/40/53/-3/0.00/0/776/89 24 WNW 5/14 71/48/60/+3/0.07/0/280/32 22 SW TSTM 5/15 70/54/62/+5/T/0/832/95 * 37 WNW AERO 40 MPH WNW 5/16 72/48/60/+3/0.00/0/889/99 30 WNW AERO 35 MPH WNW 5/17 75/51/63/+6/0.00/0/739/84 20 SSE AERO 23 MPH SSE 5/18 63/45/54/-4/.../0/009/01 35 NE AERO 37 MPH NE 5/19 52/45/49/-9/.../0/000/00 42 NE AERO 45 MPH NE 5/20 our morning low temp: 50F; the normal low is 48F * trace of rain added, occurred in evening of 15th NEW DAILY RECORDS FOR MAY 2010 5/1 - minimum temp. of 58F equals record high minimum for the date set in 2001 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR MAY 20 HIGH 91F IN 1975,1996 LOW 37F IN 1948, 2002 PRECIP 1.65 INCHES IN 1969 PEAK GUST 57 MPH S IN 1963, WNW IN 1982 RECORDS FOR MAY 21 HIGH 92F IN 1921 LOW 35F IN 1907 PRECIP 1.61 INS IN 1954 PEAK GUST 74 MPH WSW IN 2006 TODAY'S REPORT PREPARED BY: Robert Skilling/Kristy Stewart