BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, MAY 23, 2015 ALL TIMES ARE IN EASTERN STANDARD TIME NEAR RECORD COLD FOR LATE MAY AT 40 DEGREES VERY DRY AIR MASS WITH DEW POINTS IN THE 20'S FOREST FIRE STARTS ABOUT 2 MILES NORTHEAST The low temperature of 40F this morning was just 2 degrees short of the record low temperature for this date of 38F set in 1976. The air mass is very dry today with W-NW winds which are occasionally gusty to 25 to 30 MPH. A forest fire broke out by mid-morning in woodlands about 2 miles NE of the summit and smoke was seen drifting E to ESE. Today's Observations: 7 A.M. Weather: Clear, few cumulus/stratocumulus distant ESE and mostly distant SSW-WSW Temperature: 45F; Dew Point: 21F; Wind: NW at 13G20 kts Sea-level pressure: 30.31 ins. Hg, rising then more slowly Visibility: 80 miles 6-hr Max temp: 49F 6-hr Min temp: 40F 24-hr precip: 0.00 BHO SA 1155 CLR 80 264/45/21/3213G20/031/ FEW CU/SC DSNT ESE AND MSTLY DSNT SSW-WSW/ 8/800 51032 10049 20040 10 A.M. Weather: Clear, SKC, forest fire 2 miles NE, smoke drifting to the E-ESE Temperature: 52F; Dew Point: 22F; Wind: WNW at 15G21kts, Wind: Gust to 25 kts past hour Sea-level pressure: 30.32 ins. Hg, rising then more slowly BHO SA 1455 CLR 75 269/52/22/2915G21/032/ SKC FOREST FIRE 2 MI NE K PLUME DRFTNG ESE TO E VSBY OCNL LWRG ENE WND GUST 25 KTS PST HR/ 51005 1 P.M. Weather: Clear, SKC, forest fire 2 miles NE, thin smoke drifting NE-ESE Temperature: 59F; Dew Point: 21F; Wind: WNW at 135G19 kts Sea-level pressure: 30.32.80 ins. Hg, falling slightly Visibility: 70 miles, light distant haze 6-Hr Max temp: 60F 6-Hr Min temp: 45F BHO SA 1745 CLR 70 268/59/21/2913G19/032/ SKC FOREST FIRE 2 MI NE THN K DRFTG NE-ESE/ 58001 10060 20045 SUMMARY FOR FRIDAY, MAY 22, 2015 TEMPERATURE (DEGREES F) MAX.....73 NORMAL.....68 MIN.....49 NORMAL.....49 MEAN....55 NORMAL.....59 DEPARTURE FROM 30-YEAR NORMAL........................-4 TOTAL DEPARTURE FOR THE MONTH.......................+98 [+4.5 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY...............4 DEPARTURE...........-3 TOTAL HEATING UNITS FOR THE MONTH.............117 DEPARTURE..........-98 TOTAL HEATING UNITS FOR THE SEASON...........6388 DEPARTURE.........+138 TOTAL HEATING UNITS LAST SEASON TO DATE......6313 DIFFERENCE.........+75 COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY..............0 DEPARTURE..........-1 TOTAL COOLING UNITS FOR THE MONTH.............16 DEPARTURE..........+5 TOTAL COOLING UNITS FOR THE SEASON............16 DEPARTURE..........+3 TOTAL COOLING UNITS LAST SEASON TO DATE.......13 DIFFERENCE.........+3 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY..................32 WNW AT 8:31 P.M. * ASOS.......................39 W AT 4:01 P.M. DAVIS......................36 WNW AT 8:30 P.M. RMY 36 FASTEST MILE FOR YESTERDAY....................26 W AT 4:01 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE.................29 W AT 4:01 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE................25 WSW AT 2:16 P.M. AVERAGE WIND SPEED AND DIRECTION............. ASOS......................13.5 DAVIS.....................12.2 W [270 deg.] * last of several occurrences.. PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.00 DEPARTURE.....-0.14 ASOS...............0.00 TOTAL PRECIPITATION FOR THE MONTH...........0.63 DEPARTURE.....-2.12 ASOS...............0.63 TOTAL PRECIPITATION FOR THE YEAR...........18.55 DEPARTURE.....-2.62 ASOS................N/A *** *** ASOS annual totals not available due to erroneous readings 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......0.0 TOTAL SNOWFALL FOR THE SEASON..............150.8 DEPARTURE....+88.1 PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY GUST RMY: R.M. Young wind gust recording system TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 5/1 52/37/45/-8/0.00/0.0/354/42 21 NE RMY 20 5/2 63/35/49/-4/0.00/0.0/668/79 20 S RMY 20 5/3 74/44/59/+6/0.00/0.0/509/60 22 S RMY 22 5/4 83/47/65/+11/0.00/0.0/783/92 39 SSW RMY 45 5/5 77/56/67/+13/0.03/0.0/222/26 29 SW RMY N/A 5/6 74/54/64/+10/0.00/0.0/574/67 24 SSW RMY 25 5/7 84/52/68/+13/0.00/0.0/824/96 29 S RMY 32 5/8 74/44/59/+4/0.00/0.0/809/94 27 NNE RMY 26 5/9 77/44/61/+6/0.00/0.0/509/59 30 S RMY 32 5/10 88/60/74/+19/0.00/0.0/692/80 28 SSW RMY 30 5/11 84/48/66/+10/0.00/0.0/529/61 30 NE RMY 31 5/12 84/47/66/+10/0.24/0.0/287/33 33 WNW RMY 37 5/13 67/47/57/+1/0.00/0.0/820/94 31 WNW RMY N/A 5/14 70/44/57/+0/0.00/0.0/.../.. 22 NW RMY 22 5/15 73/51/62/+5/0.00/0.0/.../.. 20 WSW RMY 21 5/16 68/53/61/+4/T/0.0/.../.. 23 S RMY 24 5/17 79/50/65/+8/T/0.0/.../.. 21 NE RMY N/A 5/18 62/48/55/-3/..../0.0/.../.. 25 NE RMY N/A 5/19 63/50/57/-1/0.36/0.0/.../.. 24 S RMY 26 5/20 66/46/56/-2/0.00/0.0/.../.. 32 WNW RMY 37 5/21 66/43/55/-4/..../0.0/.../.. 24 S RMY 24 5/22 73/49/61/+2/T/0.0/.../.. 32 NW RMY 36 5/23 low since midnight is 40F; normal low is now 50F DAILY RECORDS FOR MAY 2015 NONE SO FAR. 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: Robert Skilling