BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, AUGUST 21, 2010 ALL TIMES ARE IN EASTERN STANDARD TIME PARTLY SUNNY AND WARM TODAY WITH INCREASING CLOUDS THIS AFTERNOON... There was a strong inversion this morning, as indicated by the low temperature of 58 on the summit and the low of 43 degrees at nearly Norwood Airport in the valley to the southwest. High clouds this morning are increasing with lower altocumlus moving through early this afternoon. Today's observations: 7 A.M. Weather: Scattered cirrus, thin broken cirrus, thin smoke layer along horizon NNW-NNE Temperature: 64F, Dew point: 48F; Wind: NE at 6 kts Wind: Light and variable Sea-level pressure: 30.10 inches Hg, rising Visibility: 60 miles 6-hour minimum temp: 58F BHO SA 1155 200 SCT 250 –BKN 60 194/64/48/0406/010/ THN K LYR ALG HRZN NNW-NNE WND LGT AND VRB/ 8/001 51017 10064 20058 10 A.M. Weather: Scattered cirrus, thin overcast cirrus, few small cumulus forming E-SSE, few cumulus fractus Temperature: 73F, Dew point: 50F; Wind: SSE at 5 kts Wind: Light and variable Sea-level pressure: 30.12 inches Hg, rising Visibility: 70 miles BHO SA 1455 200 SCT 250 –OVC 70 201/73/50/1505/012/ FEW SML CU FRMG E-SSE FEW CUFRA E WND LGT AND VRB/ 8/101 50007 1 P.M. Weather: Scattered altocumulus, scattered dense cirrus, thin overcast cirrus fibratus and cirrocumulus, few altocumulus lenticularis NW-NE, few cumulus all quadrants Temperature: 79F, Dew point: 49F; Wind: WNW at 5 kts, Wind: Light and variable Sea-level pressure: 30.09 inches Hg, falling Visibility: 70 miles 6-hour max. temp: 81F BHO SA 1755 140 SCT 200 SCT 250 –OVC 70 188/79/49/ 2905/009/ FEW CC OVHD-E FEW ACSL NW-NE FEW CU ALQDS WND LGT AND VRB/ 8/131 58013 10081 20064 WEATHER SUMMARY FOR FRIDAY, AUGUST 20 TEMPERATURE (DEGREES F) MAX.....86 NORMAL.....78 MIN.....63 NORMAL.....61 MEAN....75 NORMAL.....69 DEPARTURE FROM 30-YEAR AVERAGE.................+6 TOTAL DEPARTURE FOR THE MONTH.................+63 [+3.0 DEGREES/DAY] PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............23 W AT 12:13 P.M. * AEROVANE..............25 W AT 12:50 P.M. * ASOS..................24 W AT 12:05 P.M. DAVIS.................25 W AT 10:43 A.M. THE FASTEST MILE FOR YESTERDAY...........18 W AT 11:48 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE............17 WNW AT 11:49 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........19 W AT 11:48 P.M. AVERAGE WIND SPEED AND DIRECTION........9.8 W ASOS.................8.7 DAVIS................9.2 WNW [284 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..........1.21 DEPARTURE........-1.36 ASOS..............1.21 TOTAL PRECIPITATION FOR THE YEAR..........38.56 DEPARTURE........+6.58 ASOS.............38.25 ** ** ASOS missing rainfall due to system failure on 6/24-25 PRELIMINARY CLIMATE SUMMARY FOR AUGUST 2010 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/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 8/1 79/59/69/-3/0.00/512/59 22 SE 8/2 82/61/72/0/0.00/614/71 24 S 8/3 83/64/74/+2/0.00/397/46 32 SSW AERO 36 MPH SSW 8/4 89/71/80/+8/0.00/421/49 27 SSW 8/5 89/71/80/+8/0.86/103/12 30 W AERO 35 MPH W TSTM 8/6 85/62/74/+2/0.00/693/81 33 W AERO 36 MPH W 8/7 79/58/69/-2/0.00/768/90 28 SSW 8/8 84/63/74/+3/0.00/664/78 30 S 8/9 91/69/80/+9/T/637/75 25 WSW 8/10 87/69/78/+7/0.17/660/78 18 WSW 8/11 80/66/73/+2/0.00/819/97 22 NNE 8/12 80/65/73/+2/T/362/43 21 E 8/13 77/61/69/-2/0.00/780/93 22 ENE 8/14 81/58/70/0/0.00/787/94 22 SSE 8/15 78/59/69/-1/0.00/309/37 24 SSE 8/16 78/63/71/+1/0.17/.../.. 33 S AERO 36 MPH S 8/17 90/70/80/+10/T/.../.. 25 WSW AERO 27 MPH WSW 8/18 83/66/75/+5/0.00/.../.. 16 SSW 8/19 88/64/76/+6/0.01/.../.. 22 SW 8/20 86/63/75/+6/0.00/.../.. 23 W 8/21 morning low temp: 58F; the normal low is 60F NEW DAILY RECORDS FOR AUGUST 2010 None DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR AUGUST 21 HIGH 92F IN 1937, 1995 LOW 47F IN 1982 PRECIP 2.84 INCHES IN 1888 PEAK GUST 54 MPH WSW IN 2004 RECORDS FOR AUGUST 22 HIGH 90F IN 1939 LOW 42F IN 1894 PRECIP 2.28 INCHES IN 1935 PEAK GUST 44 MPH SSW IN 1987 TODAY'S REPORT PREPARED BY: Mike Iacono