Today is the last day of meteorological summer! It is also the second day of what may turn into the longest heat wave of the year. It warmed up to 90 yesterday and the temperature should climb to the lower 90s this afternoon. Highs in the lower 90s are a pretty good bet through Thursday. Today's heat will ensure that this is the third-warmest August on record in Central Park.

Sometime tonight a back door cold front, a front that sneaks down from New England rather than from the west, will pass through the region. That passage will give us a slight break on the humidity on Tuesday, but it will be plenty steamy again on Wednesday and Thursday when a big blob of a hot and humid air mass will be sitting right on top of us. You might think a few showers or thunderstorms would break out given the heat and humidity, but the jet stream is arcing way northward right now and that upper-level ridge is strong enough to suppress any convective burbling from below.

A stronger back door cold front is expected to arrive late Thursday. It's not yet clear if that front will carry the strength to make rain but it should bring slightly cooler weather for Labor Day weekend. It will still be plenty warm with highs in the mid 80s on Friday and Saturday warming to the upper 80s on Sunday and perhaps returning to 90 next Monday.