Tuesday, June 25, 2013

Wet Junes and Subsequent Months, Part Two

As we approach nine and perhaps ten inches of rain this month, putting us in the running for the wettest June since modern climate records started in the 1870's, we talked ten days back about the rain begets rain aspect of the following months, as well as the tropical connection that most of these years provided in terms of a storm hitting or tracking somewhere very close to the East Coast.

Temperatures are a different story.  That story is best told in the blurb provided by the National Weather Service as presented below.

In general, temperatures for the balance of summer are more of a mixed bag.  If we look at the last two years in the sample, which are probably more representative of modern climate, we do end up running warm down the stretch, perhaps with August carrying a warmer departure to average than July does.  Going through the whole of Philly's climate record, that trend does shift much more heavily into a mixed bag direction.

With the exception of 1887 (July) or 1973 (August), none of the years make a run at warmest July or August on record.  At least we have that going for us.

If you recall our discussion on this, the pattern that sets up such a rainy June tends to manifest itself with at least one other very rainy month through September...perhaps influenced by a tropical system of some note.  Whether that tropical connection develops later on this summer is, of course, still very much to be determined...but past history does suggest a higher risk than usual.