BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY MONDAY, APRIL 22, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME IN RECORDS CHECKED BACK TO 1942.... SECOND HIGHEST APRIL BAROMETRIC PRESSURE THIS MORNING HIGHEST PRESSURE FOR APRIL 30.84 INS. MSL IN 1973 THIS MORNING, 30.74 INS. MSL ABOUT 10:45 AN EDT An unusually strong high pressure system for April was centered over New Brunswick with central pressure approximately 1045 MB or 30.86 inches corrected to mean sea level. At the same time here at Blue Hill we recorded 1041.1 MB or 30.74 inches for our second highest pressure in any April in records checked back to 1942. The highest is 30.84 inches in April 1973. Today's observations: 7 A.M. Weather: Scattered cirrus, sky clearing past hour, mostly clear sky overhead-SSE-WSW, cirrus, cirrostatus Temperature: 42F; Dew Point: 33F; Wind: ENE at 9 kts, Wind: Direction variable NNE-E Wind: Direction gradually veering Sea-level pressure: 30.71 ins. Hg, rising then more rapidly Visibility: 30 miles, except 40 miles NE-E and 45 miles above dissipating inversion WNW, hazy 6-hour min. temp: 35F BHO SA 1155 250 SCT 30 401/42/33/0709/071/ FEW CUFRA FRMG E SKY CLRG PST HR MSTLY CLR OVHD-SSE-W CS/CI LYR NW-NE THN K LYR ALG HRZN DSNT SSW-W VSBY NE-E 40 AND 45 WNW ABV DSSPTG INVSN HAZY ALQDS WND 02V09 WND GRDLY VEERING/ 8/108 53007 10042 20035 10 A.M. Weather: Thin scattered cirrus, cirrocumulus, few cumulus fractus, cumulus, and stratocumulus W-NNE and E-SSE, layer dense cirrus ESE-S slowly invading sky Temperature: 48F; Dew Point: 23F; Wind: E at 14G20 kts, Wind: Direction variable NE-ESE, Wind: Gust to 24 kts past hour Sea-level pressure: 30.74 ins. Hg, rising steadily Visibility: 55 miles distant haze BHO SA 1455 250 –SCT 55 408/48/23/0814G20/074/ FEW CUFRA/CU/SC W-NNE AND E-SSE DNS CI LYR DSNT ESE-S SLWLY INVADING FEW CC OVHD-NW-N DSNT HZ GST TO 24 KTS PST HR WND 04V11/ 8/802 52007 1 P.M. Weather: Scattered dense cirrus, broken dense cirrus, broken cirrus, few cumulus/stratocumulus distant NNW-N and E-S, dense cirrus invading, mostly clear distant W-NNE, distant haze Temperature: 47F; Dew Point: 27F; Wind: ENE at 17G23 kts, Wind: Direction variable NNE-ESE, Wind: Gust to 25 kts past hour Sea-level pressure: 30.70 ins. Hg, falling then more slowly Visibility: 55 miles, distant haze 6-hour max temp: 49F BHO SA 1755 200 SCT E220 BKN 250 BKN 55 395/47/27/0717G23/070/ FEW CU/SC DSNT NNW-N AND E-S DNS CI ALQDS INVDNG LYR E-SW MSTLY CLR DSNT W-NNE WND 03V11 GST 25 KTS PST HR DSNT HZ/ 8/802 56013 10049 20042 WEATHER SUMMARY FOR SUNDAY, APRIL 21 TEMPERATURE (DEGREES F) MAX.....53 NORMAL.....58 MIN.....31 NORMAL.....40 MEAN....42 NORMAL.....49 DEPARTURE FROM 30-YEAR NORMAL....................-7 TOTAL DEPARTURE FOR THE MONTH...................+38 [+1.6 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............23 DEPARTURE..........+7 TOTAL HEATING UNITS FOR THE MONTH...........383 DEPARTURE.........-39 TOTAL HEATING UNITS FOR THE SEASON.........5403 DEPARTURE........-502 TOTAL HEATING UNITS LAST SEASON TO DATE....4569 DIFFERENCE.......+834 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...............31 WNW AT 12:38 A.M. AERO....................25 WNW AT 12:38 A.M. ASOS....................31 WNW AT 12:38 A.M. DAVIS...................31 WNW AT 12-1 A.M. RMY: N/A THE FASTEST MILE FOR YESTERDAY.............23 WNW AT 12:41 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE..............23 WNW AT 12:42 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.............24 WNW AT 12:1 A.M. AVERAGE WIND SPEED AND DIRECTION.........10.0 NNW ASOS...................9.1 DAVIS..................9.5 NW [320 deg] 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..........1.73 DEPARTURE...........-1.61 ASOS..............1.68 TOTAL PRECIPITATION FOR THE YEAR..........15.82 DEPARTURE...........-1.52 ASOS..............N/A* *ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0 DEPARTURE.............0.0 TOTAL SNOWFALL FOR THE MONTH.............Trace DEPARTURE............-2.7 TOTAL SNOWFALL FOR THE SEASON.............99.0 DEPARTURE...........+36.6 PRELIMINARY CLIMATE SUMMARY FOR APRIL 2013 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane wind recording system gust RMY: RMY = R.M. Young wind gust recording system added 8/9/2011 TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 4/1 61/31/46/+5/0.34/0.0/458/60 40 W AERO 44 MPH WNW RMY 46 TSTM 4/2 40/27/34/-7/T/T/460/60 45 W AERO 42 MPH W RMY 47 4/3 45/27/36/-6/0.00/0.0/755/98 44 W AERO 43 MPH W RMY 47 4/4 55/26/41/-1/0.00/0.0/719/93 30 WSW AERO 27 MPH WSW RMY 31 4/5 59/36/48/+5/0.00/0.0/403/52 33 NNW AERO 28 MPH NNW RMY 38 4/6 47/30/39/-4/0.00/0.0/747/96 38 NW AERO 35 MPH NW RMY 40 4/7 52/31/42/-1/0.00/0.0/391/50 51 S AERO 46 MPH S RMY 50 4/8 65/43/54/+10/T/0.0/494/63 29 SSW AERO 22 MPH SSW RMY N/A 4/9 72/44/58/+14/T/0.0/456/58 35 WNW AERO 35 MPH WNW RMY 39 TSTM 4/10 64/43/54/+9/0.13/0.0/426/54 23 SE AERO 20 MPH SE RMY 25 4/11 52/40/46/+1/0.09/0.0/063/08 18 ENE AERO 14 MPH ENE RMY N/A 4/12 40/34/37/-8/0.58/T/000/00 38 E AERO 32 MPH E RMY 41 4/13 52/34/43/-3/0.04/0.0/128/16 31 NNE AERO 27 MPH NNE RMY 21 4/14 52/36/44/-2/0.00/0.0/216/27 31 WNW AERO 27 MPH WNW RMY 32 4/15 55/35/45/-2/0.00/0.0/514/64 21 ESE AERO 15 MPH S RMY N/A 4/16 62/38/50/+3/T/0.0/540/67 44 S AERO 40 MPH S RMY 45 4/17 67/48/58/+11/T/0.0/769/95 29 SSW AERO 25 MPH SSW RMY N/A 4/18 65/43/54/+6/0.00/0.0/.../.. 30 S AERO 25 MPH S RMY N/A 4/19 72/50/61/+13/..../0.0/.../.. 47 SSW AERO 48 MPH SSW RMY 50 4/20 62/39/51/+2/..../0.0/.../.. 43 SSW AERO 41 MPH SSW RMY N/A 4/21 53/31/42/-7/0.00/0.0/.../.. 31 WNW AERO 25 MPH WNW RMY N/A 4/22 morning low temp: 35F; the normal low is now 40F DAILY RECORDS FOR APRIL 2013 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR APRIL 22 HIGH 85 IN 1977, 2001 LOW 26 IN 1981 PRECIP 1.85 IN. IN 2000 SNOWFALL 3.0 IN. IN 1940 PEAK GUST 68e MPH NW IN 1945 RECORDS FOR APRIL 23 HIGH 85 IN 1908, 2007 LOW 25 IN 1933,1989 PRECIP 1.99 IN. IN 2012 SNOWFALL 2.0 IN. IN 2012 PEAK GUST 64 MPH WNW IN 1962 TODAY'S REPORT PREPARED BY: Robert Skilling