Freeze watch; snowflakes?

For the first time in over six months, the official temperature in Philadelphia climbed past 80 yesterday, cresting at 82.

And it was probably unrealistic to expect the remnants of one of the all-time winters to give up so precipitously.

The National Weather Service has posted a "freeze watch" for Philadelphia, the adjacent counties on both sides of the river, and northern Delaware, with lows Wednesday morning expected from upper 20s to the low 30s.

A cold front is due to crash through tomorrow afternoon, setting off potentially heavy rains, possibly a thunderstorm, and even wet-snow showers in the early morning hours.

Should the temperature reach 32 Wednesday, that would represent the latest official freezing reading in Philadelphia since 1983.

That year, a very late-season accumulating snow began on the 19^th and continued into the early morning hours of the 20^th, when the temperature held at 32 until daybreak.

In recent years, that final day of freezing temperatures at Philadelphia International Airport has tended to occur earlier, and historically, the date has shown considerable decadal variability.

During the last 20 years, the average final-freeze date on average has been March 29, and temperatures have failed to get as low as freezing in 12 of those years.

By comparison, temperatures fell to 32 in April for 17 consecutive years, from 1969 through 1985, with an average last-freeze day of April 10.