SUMMER ANALOGS FOR 2010
IN SPITE OF THE WETNESS LEADING INTO IT AND ALSO IN MARCH, FOR THE
SECOND CONSECUTIVE SPRING, WE HAD A RELATIVELY RARE COMBINATION OF
BOTH AN UNSEASONABLY WARM APRIL AND MAY IN PHILADELPHIA. SINCE 1872,
THIS COMBINATION HAS OCCURRED ONLY NINETEEN TIMES, BUT NOW SEVEN
TIMES SINCE 1990. BY DEFINITION UNSEASONABLY COOL/NORMAL/UNSEASONABLY
WARM MONTHS ARE DIVIDED INTO THIRDS. ITS ALSO RARE TO HAVE WARM
APRILS AND MAYS COMING OUT OF A MODERATE OR GREATER EL NINO WINTER.
THIS HAS ACCOUNTED FOR ONLY THREE OF THE NINETEEN SPRING OCCURRENCES.
THE FOLLOWING ARE TEMPERATURES AND PRECIPITATION THAT OCCURRED IN
PHILADELPHIA DURING THE ENSUING SUMMERS. PLEASE NOTE BECAUSE THIS
SAMPLE SIZE IS VERY SMALL THE MARGIN FOR ERROR IS GREATER THAN
AVERAGE. SUNSCREEN ANYONE?
YEAR JUNE AVG JULY AVG AUGUST AVG SUMMER AVG SUMMER PCPN
1941 71.6 76.1 73.1 73.6 15.62
1995 74.3 81.5 79.9 78.5 4.69
1998 71.5 77.5 78.0 75.7 7.96
AVG 72.4 78.4 77.0 75.9 9.42
1971-2000 NML 72.3 77.6 76.3 75.4 11.50
THE OFFICIAL CPC OUTLOOK FOR THE SUMMER IS FOR EQUAL CHANCES OF IT
IT BEING EITHER WARMER OR COOLER THAN NORMAL.