BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, MAY 31, 2008 ALL TIMES ARE IN EASTERN STANDARD TIME UNLESS NOTED SOUTH WINDS BRINGING IN MORE HUMID AIR AND SHOWERS TODAY... LOW CLOUDS AND FOG MOVING IN AT MID-AFTERNOON... Winds now averaging 22 mph and gusting to 35 mph from the S-SSE have raised the dew point to near 60 deg F today. Showers and thundershowers have been occurring inland to the NW this morning, though none were observed on the summit through early afternoon. Low clouds and fog are moving in as of 2 PM EDT, and the first rain shower began here at 2:20 PM EDT. Today's observations: 8 A.M. EDT Weather: Scattered altocumulus, thin broken cirrus Temperature: 61F, Dew point: 53F, Wind: SSE at 18 kts Sea-level pressure: 29.88 inches Hg, falling Visibility: 30 miles 6-hourly minimum temperature: 59F BHO SA 1155 150 SCT 250 –BKN 30 117/61/53/1618/988/ HAZY/ 8/031 58017 10061 20059 11 A.M. EDT Weather: Scattered altocumulus, scattered dense cirrus, overcast cirrus; few cumulus, thin spots in overcast with towering cumulus visible distant W-NW, hazy Temperature: 70F, Dew point: 60F, Wind: S at 21G26 kts Wind: Peak gust past hour 30 kts, S at 10:40 AM EDT Sea-level pressure: 29.78 inches Hg, falling Visibility: 20 miles, 15 miles NW-NE, hazy BHO SA 1455 140 SCT 200 SCT E250 OVC 20 148/70/60/1721G26/978/ FEW CU FEW TCU DSNT W-NW THN SPTS IOVC HAZY VSBY NW-NE 15 PK WND 1730/40 WND 14V20/ 8/231 56031 2 P.M. EDT Weather: Overcast stratus, thin fog forming Temperature: 62F, Dew point: 60F, Wind: S at 17G25 kts Wind: Peak gust past hour 30 kts, SSE at 1:13 PM EDT Sea-level pressure: 29.70 inches Hg, falling Visibility: 6 miles, thin fog, visibility decreasing 6-hourly maximum temperature: 73F BHO SA 1755 E12 OVC 6F 122/62/60/1817G25/970/ VSBY DCRG VSBY E-SE 10 PK WND 1630/13/ 8/6// 56026 10073 20061 WEATHER SUMMARY FOR FRIDAY, MAY 30 TEMPERATURE (DEGREES F) MAX.....69 NORMAL.....71 MIN.....55 NORMAL.....51 MEAN....62 NORMAL.....61 DEPARTURE FROM 30-YEAR NORMAL............+1 TOTAL DEPARTURE FOR THE MONTH...........-43 [-1.6 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............3 DEPARTURE........-2 TOTAL HEATING UNITS FOR THE MONTH...........290 DEPARTURE.......+24 TOTAL HEATING UNITS FOR THE SEASON.........5901 DEPARTURE......-391 TOTAL HEATING UNITS LAST SEASON TO DATE....5828 DIFFERENCE......+73 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............29 SSE AT 10:03 P.M. AEROVANE.............28 SSE AT 10:03 P.M. ASOS.................29 S AT 10:03 P.M. DAVIS................28 SE AT N/A FASTEST MILE FOR YESTERDAY..............19 SSE AT 9:52 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........20 S AT 10:04 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........19 SSE AT N/A AVERAGE............12.8 NE ASOS...............12.2 DAVIS..............12.8 ENE [71 deg] * last of several occurrences. PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE......-0.13 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........1.82 DEPARTURE......-1.84 ASOS..............1.73 TOTAL PRECIPITATION FOR THE YEAR..........22.58 DEPARTURE......+0.97 ASOS.............24.96 # # Includes erroneous ASOS precipitation data on 2/13/08. PRELIMINARY CLIMATE SUMMARY FOR MAY 2008 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system when significant TSTM: Thunderstorm day ....: Data not yet available, records not finalized 5/1 60/35/48/-4/0/786/93 30 W Aero 28 MPH W 5/2 48/42/45/-7/0.07/000/00 21 ENE 5/3 43/41/42/-11/0.09/000/00 25 E 5/4 50/42/46/-7/0.17/000/00 27 E 5/5 69/40/55/+2/0/752/88 24 ESE 5/6 74/46/60/+6/0/686/80 25 W 5/7 75/48/62/+8/0/722/84 29 S 5/8 75/54/65/+11/0.08/172/20 42 W Aero 42 MPH W 5/9 56/43/50/-5/0.26/000/00 30 NE 5/10 57/44/51/-4/T/407/47 35 NNE 5/11 58/41/50/-5/0/747/86 24 ENE 5/12 47/42/45/-11/0/017/02 43 NNE Aero 43 MPH NNE 5/13 63/43/53/-3/0/812/93 47 NNE Aero 50 MPH NNE 5/14 64/47/56/-1/0/788/90 23 ENE 5/15 67/47/57/0/T/009/01 22 S 5/16 59/45/52/-5/0.49/009/01 21 ENE 5/17 72/46/59/+2/0.47/449/51 33 W 5/18 71/50/61/+3/0.02/494/56 30 S 5/19 59/44/52/-6/0/566/64 46 W Aero 44 MPH W 5/20 64/42/53/-5/0.01/461/52 29 S 5/21 69/46/58/-1/T/524/59 35 WSW Aero 32 MPH WSW 5/22 58/45/52/-7/0.01/089/10 26 WSW 5/23 70/43/57/-2/T/749/84 41 W Aero 40 MPH W 5/24 69/47/58/-2/T/456/51 32 WNW 5/25 75/50/63/+3/0/.../.. 29 SE 5/26 78/52/65/+5/T/.../.. 42 S 5/27 80/53/67/+6/0.15/.../.. 35 NNW 5/28 66/47/57/-4/0/.../.. 35 NW Aero 32 MPH NW 5/29 76/45/61/0/0/.../.. 33 W 5/30 69/55/62/+1/0/.../.. 29 SSE 5/31 morning low temp. 59F; our normal low is now 51F NEW DAILY RECORDS FOR MAY 2008 None to date. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR MAY 31 HIGH 92F IN 1944,1987 LOW 35F IN 1961 PRECIP 5.02 INS 1984 (RECORD FOR MAY) PEAK GUST 54e MPH WNW IN 1945 RECORDS FOR JUNE 1 HIGH 90F IN 1937 LOW 36F IN 1945 (RECORD FOR JUNE) PRECIP 2.28 INS IN 1992 PEAK GUST 51e MPH SE IN 1952 TODAY'S REPORT PREPARED By: Mike Iacono