BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY MONDAY, DECEMBER 6, 2010 ALL TIMES ARE IN EASTERN STANDARD TIME INCREASINGLY COLD AND GUSTY WSW-W WINDS TODAY AS BAROMETRIC PRESSURE FALLS TO NEAR 29.20 INS. BY EARLY THIS AFTERNOON SUN PILLAR OBSERVED JUST BEFORE SUNRISE An intense low pressure system over northern Maine and the neighboring Atlantic maritime provinces of eastern Canada has a central pressure well down under 29 inches or around 28.6 inches or possibly lower early this afternoon. The storm center appears to be looping to the west. Rain is occurring in far northern Maine with temperatures well into the 30's. At the same time here we have very gust west-southwest veering to west winds importing colder air with high temperatures just around 32F along with wind gusts of 30-40 MPH. A "sun pillar" or beam of sunlight rising above the horizon point of sunrise was clearly and strikingly visible just before the sun rose at 6:57 A.M. as observed here at the summit. Today's observations: 7 A.M. Weather: Overcast stratocumulus, cumulus, few moderate tops, and lower stratocumulus layer along/offshore NE-SE-SSW, break in overcast ESE-S and few thin spots in the overcast, sun pillar above point of sunrise ESE, virga Temperature: 235F, Dew point: 16F; Wind: WSW at 16G24 kts, Sea-level pressure: 29.38 inches Hg, falling Visibility: 60 miles 6-hour minimum temp: 22F BHO SA 1155 E55 OVC 60 949/23/16/2516G24/938/ CU/SC FEW MDT TOPS LYR ALG/OFFSHR NE-SE-SSW BINOVC ESE-S FEW THN SPTS IOVC SUN PILLAR OVR PT OF SUNRISE ESE LGT VIRGA DSNT HZ/ 8/8// 58016 10024 20022 10 A.M. Weather: Clear, cumulus fractus and cumulus forming, stratocumulus/virga layer W-N-NNE, altocumulus lenticularis south to south-southwest, cirrus, dense cirrus later extending NNW-ENE Temperature: 28F, Dew point: 14F; Wind: WSW at 21G30 kts, Wind: Peak wind 31 kts west-southwest at 9:43 a.m. Wind: Direction variable SW to WNW Sea-level pressure: 29.32 inches Hg, falling Visibility: 50 miles BHO SA 1455 CLR 50 928/28/14/2521G30/932/ CUFRA/CU FRMG ALQDS SC/VIRGA LYR W-N-NNE ACSL S-SSW CI/DNS CI LYR XTDNG NNW-ENE PK 2531/43/ WND 23V30/ 8/842 58021 1 P.M. Weather: Scattered stratocumulus, scattered altocumulus lenticularis, scattered cirrus/dense cirrostratus layer W-N-ENE, snow virga offshore distant ENE-ESE Temperature: 31F, Dew point: 14F; Wind: W at 23G30 kts, Wind: Peak wind 31 kts west @ 12:06 p.m. Wind: Direction variable SW to WNW Sea-level pressure: 29.22 inches Hg, falling 6-hourly max. temp: 31F Visibility: 70 miles BHO SA 1755 41 SCT 220 SCT 70 895/31/14/2623G30/922/ ACSL S LYR CI/DNS CS XTDNG W-N-ENE SNW VIRGA OFFSHR DSNT ENE-ESE PK WND 2631/06/ WND 24V30/ 8/542 56033 10031 20023 WEATHER SUMMARY FOR SUNDAY, DECEMBER 5 TEMPERATURE (DEGREES F) MAX.....34 NORMAL.....42 MIN.....23 NORMAL.....27 MEAN....29 NORMAL.....35 DEPARTURE FROM 30-YEAR NORMAL................-6 TOTAL DEPARTURE FOR THE MONTH................+8 [+1.4 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............36 DEPARTURE........+6 TOTAL HEATING UNITS FOR THE MONTH...........140 DEPARTURE........-8 TOTAL HEATING UNITS FOR THE SEASON.........1300 DEPARTURE......-137 TOTAL HEATING UNITS LAST SEASON TO DATE....1269 DIFFERENCE......+31 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY..............24 W AT 6.22 P.M. AEROVANE...............27 W AT 6:22 P.M. ASOS.................. 23 W AT 9:32 P.M. DAVIS..................25 W AT 11:10 A.M. THE FASTEST MILE FOR YESTERDAY............17 W AT 6:22 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE.............18 W AT 6:21 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE............19 W AT 7:34 P.M. AVERAGE WIND SPEED AND DIRECTION..........11.2 W ASOS...................10.8 DAVIS..................10.8 W [270 DEG] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE........-0.15 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........0.49 DEPARTURE........-0.26 ASOS..............0.53 TOTAL PRECIPITATION FOR THE YEAR..........58.52 DEPARTURE.......+11.11 ASOS.............58.44** ** ASOS missing rainfall due to system failure on 6/24-25 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0 DEPARTURE.....-0.3 TOTAL SNOWFALL FOR THE MONTH................0.0 DEPARTURE.....-1.1 TOTAL SNOWFALL FOR THE SEASON...............0.1 DEPARTURE.....-3.9 PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 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 12/1 55/43/49/+13/0.49/0.0/000/00 55 SE AERO 61 MPH SE 12/2 48/29/39/+3/0.00/0.0/.../.. 30 W 12/3 38/29/34/-1/0.00/0.0/.../.. 25 WNW 12/4 40/28/34/-1/0.00/0.0/.../.. 27 WNW 12/5 34/23/29/-6/0.00/0.0/.../.. 24 W 12/6 our morning low temp: 22F; the normal low is now 27F NEW DAILY RECORDS FOR DECEMBER 2010 None DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR DECEMBER 6 HIGH 70 IN 2001 LOW 5 IN 1901,1935 PRECIP 2.78 INS. IN 2003 SNOWFALL 17.0 INS. IN 2003 PEAK GUST 74 MPH NW IN 1981 RECORDS FOR DECEMBER 7 HIGH 74 IN 1998 LOW 6 IN 1906 PRECIP 1.67 INS. IN 1953 SNOWFALL 6.3 INS. IN 2003 PEAK GUST 76e SE IN 1976 TODAY'S REPORT PREPARED BY: Robert Skilling/Chris Torchia