After a few days of cooler weather masquerading as a fall preview, summertime humidity and temperatures are on the way this week for Long Island. A brief pattern shift will bring highs into the 80's by the middle of the week.
After one week of September, temperatures at MacArthur Airport, Long Island's climate site, are averaging right around normal despite recent chilly nights. The Pine Barrens even reached the low 40s in the past few days. After a warmer weekend, a brief cool down highlights continuing up-and-down temperatures for the upcoming week.
Monday, high pressure comes down from Canada, bringing ultra-low humidity and cooler temperatures. With mostly sunny skies and a stiff breeze, highs reach the low 70s, after morning lows reach the 50s in most spots. Clouds increase Monday night as a warm front approaches. This could touch off a shower into Tuesday, and the humidity levels skyrocket to uncomfortable levels by the afternoon. Clouds may keep highs in the 70s on Tuesday, but even a couple of hours of late-day sunshine may give temps a boost.
A southwest flow is featured for Wednesday, as well as a late day thunderstorm. Highs will be near 80, with some spots into the 80s, especially in Nassau County locales away from the water. A thunderstorm possibility lasts into Thursday as a cold front comes through to cool off Long Islanders for the end of the week.
Sunday saw the National Hurricane Center upgrade a tropical wave near the Cape Verde Islands to Tropical Depression 9 (and may be a tropical storm, and in turn becomes Humberto, after press time). This storm is expected to become the first hurricane of the season, close to the record latest date for such an occurrence since 1950. It is no threat to the U.S. No other areas of interest are expected to be big threats in the next few days.