BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA WEDNESDAY, SEPTEMBER 30, 2020 ALL TIMES ARE IN EASTERN STANDARD TIME QUITE STORMY THIS MORNING WITH COLD FRONTAL PASSAGE, MUCH NICER AFTERNOON.... The big story today is of course the big wind gusts we observed this morning. The official gust on our F420C wind system is 71 mph from the S at 6:48 A.M. This also sets a new record wind gust for the date beating the old record of 58 mph SSE in 1999. Our various wind systems were in pretty good respective agreement in relation to which tower they were on. Here is the listing... Observatory tower: F420C (official): 71 mph ASOS............: 72 mph Davis #1........: 71 mph RM Young........: 71 mph Merlin..........: 71 mph South Auxiliary tower: Aerovane........: 88 mph Davis #2........: 89 mph It should be noted the instrumentation on the south tower is at the same height as the instrumentation on the Observatory. The wind was associated with a strong cold front moving through the region helping to push the warm and humid air mass out. The dew point, which was in the low 70s early this morning has returned to much more comfortable levels in the low 50s this afternoon. The front also brought much needed rain to the region this morning with 1.01" storm total being measured here on the summit. Despite the rainfall, we are still under the influence of a severe drought, with some parts of the region in extreme drought. The rainfall total for the month is up to 1.61", but this is still more than 2 inches below normal. For the year to date, we are still more than 4.50" below normal. The high so far today is 72F, 6 degrees above the daily normal max of 66F. The low since midnight is 61F, which is 12 degrees above the normal low of 49F. Today's Observations: 7 A.M. Weather: Broken stratus fractus, overcast nimbostratus, light rain shower Temperature: 71F; Dew Point: 69F; Relative Humidity: 94% Wind: S at 39G62 kts, peak wind S 62 kts at 6:48 A.M.   Sea-level pressure: 29.45 ins. Hg: falling, then more rapidly Visibility: 6 miles, 4 miles S, 10 miles N-NE 6-hr Max temp: 72F 6-hr Min temp: 70F 24-hr Precip: 0.91 ins. BHO SA 1155 E10 BKN 22 OVC 6RW-F 974/71/69/1839G62/945/ VSBY 4 S 10 N-NE PK WND 1862/48/ 8/7// 58028 6090 70091 10072 20070 10 A.M. Weather: Overcast Stratus, moderate rain shower Temperature: 61F; Dew Point: 61F; Relative Humidity: 100% Wind: W at 20G33 kts, wind shift, peak wind SSW 39 kts at 9:07 A.M. Sea-level pressure: 29.55 ins. Hg: rising, then more slowly Visibility: 2 miles, fog 3-hr Precip: 0.10 ins. BHO SA 1455 E10 OVC 2RWF 006/61/61/2620G33/955/ RWB48 WSHFT 45 PK WND 2039/07/ 8/6// 51032 6010 1 P.M. Weather: Broken cumulus/stratocumulus, broken altocumulus, thin broken cirrus, cumulonimbus distant NNE Temperature: 69F; Dew Point: 53F; Relative Humidity: 56% Wind: WSW at 22G33 kts, peak wind W 39 kts at 12:32 P.M. Sea-level pressure: 29.60 ins. Hg: rising, then more rapidly Visibility: 70 miles 6-hr Max temp: 71F 6-hr Min temp: 61F 6-hr Precip: 0.11 ins. BHO SA 1755 E35 BKN 140 BKN 250 -BKN 70 023/69/53/2422G33/960/ SML CB DSNT NNE RW DSNT NNE MVG E PK WND 2639/32/ 8/332 53017 6011 10071 20061 SUMMARY FOR TUESDAY, SEPTEMBER 29, 2020 TEMPERATURE (DEGREES F) MAX.....76   NORMAL.....67 MIN.....62   NORMAL.....49 MEAN....69   NORMAL.....58 DEPARTURE FROM 30-YEAR NORMAL................+11 TOTAL DEPARTURE FOR THE MONTH................+27 [+0.7 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY............. 0  DEPARTURE..... -8 TOTAL HEATING UNITS FOR THE MONTH.............94  DEPARTURE.....-15 TOTAL HEATING UNITS FOR THE SEASON............97  DEPARTURE.....-37 TOTAL HEATING UNITS LAST SEASON TO DATE.......84  DEPARTURE.....+13 COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY............. 4  DEPARTURE..... +3                   TOTAL COOLING UNITS FOR THE MONTH............ 73  DEPARTURE.....+14 TOTAL COOLING UNITS FOR THE SEASON...........830  DEPARTURE....+234 TOTAL COOLING UNITS LAST SEASON TO DATE......680  DEPARTURE....+150 PEAK WIND GUST FOR YESTERDAY (MPH)                    420C/Official................30 S   AT 11:41 P.M.                      AERO.........................30 S   AT 11:59 P.M.                    ASOS.........................31 S   AT 11:41 P.M.                    DAVIS........................32 S   AT 11:53 P.M.                    RMY N/A  MERLIN N/A FASTEST MILE FOR YESTERDAY......................22 S   AT 11:58 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...................21 S   AT 11:56 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..................22 S   AT 11:41 P.M. AVERAGE WIND SPEED AND DIRECTION..............11.2 S (269 total miles)                            ASOS.......................11.2                    DAVIS......................10.6 S [191 deg.] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.91  DEPARTURE....+0.76                          ASOS..............0.98 TOTAL PRECIPITATION FOR THE MONTH..........1.50  DEPARTURE....-2.42                          ASOS..............1.54 TOTAL PRECIPITATION FOR THE YEAR..........34.31  DEPARTURE....-4.63                          ASOS.............35.12 PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER CALENDAR DAY DATA DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST AERO: Aerovane wind recording system 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 M:    Missing data 09/01  76/59/68/0/0.00/698/88              22 SSE  AERO 21 SE   RMY 20 09/02  69/59/64/-4/0.18/102/13             23 SSE  AERO 23 SSE  RMY 24 09/03  75/66/71/+4/0.04/000/00             22 SSW  AERO 21 SSW  RMY N/A 09/04  82/62/72/+5/0.00/763/98             26 WNW  AERO 26 WNW  RMY 25 09/05  76/55/66/-1/0.00/760/98             25 W    AERO 25 W    RMY 24 09/06  78/58/68/+1/0.00/356/46             24 W    AERO 24 W    RMY N/A 09/07  79/61/70/+4/0.00/632/82             27 SSE  AERO 30 SSE  RMY 28 09/08  82/61/72/+6/0.00/545/71             17 S    AERO 16 S    RMY 17 09/09  80/62/71/+5/0.00/214/28             16 S    AERO 15 S    RMY 16 09/10  81/69/75/+10/0.28/015/02            21 SSW  AERO 21 SSW  RMY N/A 09/11  72/55/64/-1/0.01/152/20             25 N    AERO 25 N    RMY N/A 09/12  68/51/60/-5/0.00/666/88             21 ENE  AERO 21 ENE  RMY 21 09/13  74/53/64/0/0.00/611/81              26 SSW  AERO 26 SSW  RMY 26 09/14  74/50/62/-2/0.00/511/68             29 NNW  AERO 33 NNW  RMY 30 09/15  64/44/54/-10/0.00/583/78            18 S    AERO 18 S    RMY N/A 09/16  72/49/61/-2/0.00/603/81             31 SSW  AERO 31 SSW  RMY 31 09/17  76/57/67/+4/0.00/453/61             26 WSW  AERO 28 W    RMY N/A 09/18  64/48/56/-6/0.00/163/22             28 NE   AERO 30 NNW  RMY N/A 09/19  59/42/51/-11/0.00/722/98            23 N    AERO 23 N    RMY N/A 09/20  58/40/49/-13/0.00/602/82            25 NE   AERO 25 NE   RMY 27 09/21  61/41/51/-10/0.00/.../..            29 NE   AERO 27 NE   RMY 29 09/22  63/39/51/-10/0.00/.../..            28 NNW  AERO 30 NNW  RMY 29 09/23  78/50/64/+4/0.00/.../..             31 NW   AERO 32 WNW  RMY 32 09/24  76/57/67/+7/0.00/.../..             20 SW   AERO 18 WSW  RMY 19 09/25  77/57/67/+7/0.00/.../..             18 ENE  AERO 18 WSW  RMY N/A 09/26  77/57/67/+8/0.00/.../..             21 S    AERO 21 S    RMY 21 09/27  79/64/72/+13/0.01/.../..            24 S    AERO 25 S    RMY 24 09/28  78/64/71/+13/0.07/.../..            24 SSE  AERO 24 S    RMY 25 09/29  76/62/69/+11/0.01/.../..            30 S    AERO 30 S    RMY N/A 09/30 The low since midnight is 61F, the daily normal low is 49F DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated):   RECORDS FOR SEPTEMBER 30 HIGH 84F IN 1986 LOW 31F IN 1992 PRECIP 2.44 INCHES IN 2015 PEAK GUST 58 MPH SSE IN 1999 RECORDS FOR OCTOBER 1 HIGH 85F IN 1927 LOW 30F IN 1992 PRECIP 1.63 INCHES IN 2014 PEAK GUST 68e MPH SSE IN 1977 TODAY'S REPORT PREPARED BY: Matt Douglas