BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, JUNE 2, 2005 ALL TIMES ARE IN EASTERN DAYLIGHT TIME [unless otherwise noted] Discussion at 2 p.m. THIRTEEN CONSECUTIVE DAYS WITH HEAVY FOG... Heavy fog (visibility 1/4 mile or less) was observed here at the summit again very early this morning. This makes a total of 13 consecutive days with heavy fog starting May 21. Actually, sixteen out of the past seventeen days have had heavy fog starting with May 15. This is an amazingly long stretch of days with fog and it may be very difficult to find a comparable stretch of fog days at any time of year. A complete list of all of the May 2005 monthly notes, and there are two pages of them, (very unusual), is included here below. Our thanks to Mike Iacono, Blue Hill Research Meteorologist, for preparing these interesting statistics. MAY 2005 - BLUE HILL MONTHLY NOTES SUNSHINE May 2005 with 34% is 2ND CLOUDIEST on record for May. 1) 136.1 hrs or 31% in 1888 2) 147.4 hrs or 34% in 2005 3) 150.8 hrs or 35% in 1927 4) 152.4 hrs or 35% in 1983 5) 155.0 hrs or 35% in 2003 RAINFALL May total precipitation of 8.65 inches ranks as 3RD WETTEST on record: 1) 9.16 in 1954 2) 9.14 in 1984 3) 8.65 in 2005 4) 8.18 in 1998 There were 20 days with measurable rainfall during May, which is well above average, but we don't have days with measurable rain tabulated yet for the whole record, so we can't check this easily. TEMPERATURE The 24-hour corrected mean temp of 50.3 is 4TH COLDEST on record for May. The average maximum temperature (58.7) is 3rd coldest and the average minimum (43.4) is 8th coldest. Mean Temp (corrected to 24-hours) 1) 46.0 in 1917 2) 48.3 in 1907 3) 49.8 in 1967 4) 50.3 in 2005 5) 50.5 in 1888 Max Temp 1) 54.7 in 1917 2) 58.5 in 1907 3) 58.7 in 2005 4) 59.8 in 1888 Min Temp 1) 39.7 in 1917 2) 40.4 in 1907 3) 41.1 in 1967 4) 42.1 in 1956 5) 42.4 in 1900 6) 42.7 in 1885 7) 43.3 in 1888 8) 43.4 in 2005 Page 2 of May 2005 Monthly Notes WIND Prevailing wind direction: NNE 14% The only other months since 1951 with prevailing direction of NNE were October 1951 and October 1953. N occurs about once per decade in any month, and both NE and ENE are more common with both occurring as prevailing directions last during 2003. FOG Total days with fog of 21 and 18 days of heavy fog are very high for May in recent decades. These statistics have also not been tabulated for the entire record. OTHER Number of days in May with max temperature of 70 or higher of 4 ties for the 2nd fewest number on record with 1888, 1907, and 1938 (there were 3 in May 1917 and 1927). Number of days in May with max temperature of less than 50 of 6 is the 3rd most on record behind only 10 in 1917 and 7 in 1907. The 4 consecutive days in May with temps less than 50 (5/23-26/2005) has occurred only two other times in May on the entire record (5/5-8/1917 and 5/22-25/1940) . MISCELLANEOUS The average max temp for May was colder than the April max temp! This has never before happened on the entire record. The difference in the mean temps of only +1.4 degrees is also the lowest in 120 years. The min. temp difference is the second smallest. April/ May/ Difference 59.8 58.7 -1.1 Max 39.2 43.4 +4.2 Min 48.9 50.3 +1.4 Mean Corrected to 24 hours Previously, the closest that the May temps have been to April all occurred in 1945 when the May-April max temperature difference was +1.9, the min temperature difference was +3.1, and the mean temperature difference was +2.9. Prepared by: Mike Iacono, Blue Hill Observatory Research Meteorologist and reviewed by Observer-in-Charge, Robert Skilling TODAY'S OBSERVATIONS.... 6/2/2005 THU 8 a.m. low stratus overcast at 3 hundred feet with visibility of 4 miles in light fog and visibility is increasing; temp. 51; dewpoint 49; wind ssw at 12 mph; six hourly min. temp. 48 degrees... BHO SA 1155 E3 OVC 4F 255/51/49/2010/028/ SUN DISC OCNL VSB VSBY INCRSNG/ 8/6// 51008 10051 20048 11 a.m. clear and hazy with visibility of 12 miles; temp. 63; dewpoint 52; wind ssw at 05 mph... BHO SA 1455 CLR 12 251/63/52/2104/027/ HAZY/ 58004 2 p.m. scattered cumulus and cirrus visible dsnt south; hazy vsby 15 to 20 miles; temp. 73; dewpoint 53; wind sse at 10 gusting 17 mph; six hourly max. temp. 73 deg. BHO SA 1755 40 SCT 250 SCT 20 233/73/53/1609G15/022/ CI DSNT S HAZY ALQDS VSBY NE-SE 15 WND 12V19/ 8/101 58018 10073 20051 WEATHER SUMMARY FOR WEDNESDAY, JUNE 1: TEMPERATURE (DEGREES F) MAX.....64 NORMAL.....72 HAZEN SHELTER AT: 2:44 p.m. MIN.....46 NORMAL.....52 HAZEN SHELTER AT: 4:31 a.m. MEAN....55 NORMAL.....62 DEPARTURE FROM 30-YEAR NORMAL......-7 TOTAL DEPARTURE FOR THE MONTH.... -7 PRECIPITATION (INCHES) THROUGH THIS MORNING (EDT) TOTAL PRECIPITATION 24 HRS ENDING 8 A.M....0.00 DEPARTURE....-0.13 ASOS..............0.00 TOTAL PRECIPITATION FOR JUNE TO DATE.......0.00 DEPARTURE....-0.13 ASOS..............0.00 TOTAL PRECIPITATION FOR MAY................8.65 DEPARTURE....+4.86 ASOS..............8.59 TOTAL PRECIPITATION FOR THE YEAR..........29.74 DEPARTURE....+8.02 ASOS.............28.62 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY........22 S AT 9:36 P.M. AEROVANE.........23 S AT 9:36 P.M. ASOS.............20 SE AT 7:54 P.M. DAVIS............21 S AT 9:35 P.M. FASTEST MILE FOR YESTERDAY..........15 S AT 11:55 P.M. [EASTERN STANDARD TIME] MAXIMUM 2-MINUTE ASOS AVERAGE.......16 S AT 11:55 P.M. [EASTERN STANDARD TIME] DAVIS 1-MINUTE AVERAGE..............16 SSE AT 9:37 P.M. AVERAGE WIND SPEED AND DIRECTION.. 7.6 NE [speed uncorrected] ASOS........... 8.6 MISSING DAVIS ......... 7.1 ENE [060 deg ] PRELIMINARY CLIMATE SUMMARY FOR MAY 2005/JUNE...CALENDAR DAY DATA DATA REPORTED: DATE MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST/ TSTM: thunderstorm day AERO: Aerovane recording wind system when significant TSTM: Thunderstorm day ....: Data not yet available 5/1 57/44/51/-1/0.14/118/14 33 MPH WNW 5/2 63/39/51/-1/0.05/593/70 43 MPH S 5/3 58/38/48/-5/0/604/71 30 MPH WSW 5/4 59/40/50/-3/T/400/47 21 MPH E 5/5 60/38/49/-4/0/777/91 23 MPH E 5/6 54/42/48/-6/0.08/103/12 26 MPH NNE 5/7 44/39/42/-12/1.19/000/00 58 MPH N 5/8 47/39/43/-11/0.22/000/00 43 MPH NNW 5/9 52/43/48/-7/0.04/026/03 36 MPH N 5/10 64/46/55/0/0/502/58 20 MPH E 5/11 75/46/61/+6/0/807/93 27 MPH S 5/12 60/41/51/-5/0/835/96 40 MPH NW 5/13 64/35/50/-6/0/846/97 28 MPH WNW 5/14 64/47/56/-1/T/288/33 21 MPH E 5/15 58/41/50/-7/0.14/132/15 24 MPH N 5/16 57/41/49/-8/0.11/193/22 21 MPH ENE 5/17 65/47/56/-1/0/343/39 21 MPH ESE 5/18 59/45/52/-6/0.01/203/23 28 MPH N 5/19 62/42/52/-6/0.05/681/77 25 MPH WNW 5/20 66/45/56/-2/0/310/35 24 MPH S 5/21 51/43/47/-12/0.31/000/00 35 MPH NNW 5/22 54/43/49/-10/0.03/009/01 30 MPH NW 5/23 48/43/46/-13/0.18/000/00 35 MPH N 5/24 45/41/43/-17/1.53/000/00 54 MPH NNE 5/25 46/41/44/-16/3.31/000/00 62 MPH NNE 5/26 49/43/46/-14/0.82/000/00 51 MPH NNE 5/27 64/49/57/-4/0.08/027/03 26 MPH WSW 5/28 77/53/65/+4/0.02/692/77 30 MPH WSW 5/29 70/53/61/+1/0.27/207/23 27 MPH WNW TSTM 5/30 73/52/63/+2/0.07/487/54 29 MPH NNE TSTM 5/31 56/47/52/-10/0/000/00 20 MPH NE JUNE 2005.... 6/1 64/46/55/-7/0/570/63 22 MPH S 6/2 morning low temp. 48 deg. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JUNE 2 HIGH 91F IN 1895 LOW 41F IN 1907, 1929 PRECIP 2.36 INS IN 1982 PEAK GUST 63 MPH NW IN 2000 RECORDS FOR JUNE 3 HIGH 98F IN 1919 LOW 38F IN 1929 PRECIP 1.21 INS 1947 PEAK GUST 47 MPH NW IN 1998 Today's report by: Robert Skilling