MyFoxPhilly

I talked about three months ago about the "myth" of snow droughts in the Delaware Valley. Given our relatively low average winter snowfall (21.6" over 123 winters, not including this winter), there will be periods of time where Philadelphia will see years with less bountiful quantities of snow.

While the past two years have been low on snow amounts, thanks to sleet last winter and thanks to La Nina this winter, the truth is through last winter we averaged more days with at least 0.1" of snow this decade than the 1990's and have had more 6" snow events this decade than any decade since the 1960's. Unfortunately (if you like snow), for all of the snow days we have been seeing amounts have been on the nuisance side for the most part, especially in the last couple of years. All those 0.1" and 0.2" clipper events from the past two years have added up!

In the last 15 years, Philadelphia has seen two of its ten snowiest winters (95-96 and 02-03), with seven of the last 15 years (not including this winter) featuring snowfall that is above the current 30 year "average" of 20.2". We have seen a bit of a feast/famine cycle regarding snowfall around here as six of the past 15 years have featured less than 75% of normal snowfall, including four years in five during the mid and late 1990's. As you can see in the snowfall chart I posted below snowfall in recent years has been very feast or famine.

While we have been feasting at the trough of snow then starving the following year, it could be worse. Between 1925 and 1932 Philadelphia had six years in eight where they did not receive 15" of snow, with only 1926 (19.1") and 1928 (15.5") besting 15" even though both years featured below normal snowfall. Another snow drought in Philadelphia occurred in the 1950's, with five years in the decade featuring less than 75% of our current snowfall average, with only three years above average.

While it is possible that we could be entering another lull in bountiful quantities of snowfall, the truth is until we see flakes falling from the sky guessing snowfall amounts months in advance is an inexact science. Forecasts this winter ranged from 11.6" to as much as 23" (unfortunately, my forecast) of snow and as of today only 6.3" of snow has fallen in Philadelphia. Last winter's forecasts were quite aggressive for snow given it was an El Nino winter, yet only 13" of snow fell last winter. Given the recent feast-famine cycle in snowfall in Philadelphia, it could just be a matter of time before the next bountiful snowfall winter hits us over the head. However, when that hits, don't expect a repeat performance as back-to-back 30" snowfall winters have only occurred only once in Philadelphia in the last 90 winters, and back-to-back 25" snowfall winters have occurred only seven times since 1918 and just twice since the 1960's.

Source: http://philadelphiaweather.blogspot.com/2008/03/more-o
n-snowfall-droughts.html

Phillyweather's Blog

More On Snowfall Droughts

Phillyweather

Inside Fox:
Hot List About Us Good Day TV Listings Politics

Write your comment below: Email me when a new comment is added to this entry