Why Pollen Levels Are Surging and Driving Intense Allergy Seasons

Allergy sufferers on Long Island are experiencing a simultaneous surge in tree and grass pollen, a phenomenon described as a double whammy by medical specialists. This convergence of pollen seasons is causing more intense symptoms for residents as the region transitions into summer.

The current intensity of the allergy season is attributed to specific weather patterns occurring during the preceding winter and spring. According to Erin McGintee, an allergist and immunologist at ENT and Allergy Associates in Southampton, a particularly cold winter delayed the blooming of early trees, while late-blooming trees began their cycle as soon as the weather warmed.

This synchronization of blooming periods means that multiple allergens are present in the air at the same time, rather than in a gradual sequence.

“With particularly cold winters and an early spring, everything sort of pops at once, so to speak,”

Erin McGintee

McGintee noted that when these blooming periods overlap, it can be really rough for individuals with tree pollen allergies, particularly as grass pollen begins to emerge in May.

Pollen Season Timelines

Under typical conditions, the allergy cycle on Long Island follows a staggered progression. Tree season generally commences in February and continues through April and into May.

Grass pollen typically increases in May and persists through June. This is followed by the first occurrences of weed pollen in August.

The current convergence of these seasons has led to an increase in residents struggling with common allergic reactions, including sneezing, runny noses, and red, watery eyes.

The severity of the current season was anticipated by local experts. In March 2026, Long Island allergy specialists predicted an intense tree pollen season based on the volume of rain and snow recorded over the winter.

Broader Environmental Trends

The conditions observed on Long Island align with broader trends in allergen behavior. According to the Asthma and Allergy Foundation of America, grass pollen seasons are generally becoming more intense and lasting for longer periods.

As of May 30, 2026, medical professionals indicate that residents should prepare for continued high levels of both tree and grass pollen as the region moves into longer, warmer days.