Is It Allergy Season Yet?

I The Next Five Days forecast index, 0–5 scale

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II Around You your state at a glance

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III What's In The Air today's pollen by type

Pollen	Index	Level	Trend
Tree Oak, birch, and maple carry the spring load. Peaks in April most years.	— / 5	—	—
Grass Follows the trees into May and hangs around through July.	— / 5	—	—
Weed Ragweed takes the late shift — August through the first hard frost.	— / 5	—	—

IV The Wider Season when each pollen type runs

Tree

Grass

Weed

Today

FebMarAprMay JunJulAugSepOct

Peak in —

driven by tree pollen

Season ends —

first frost, roughly

Days remaining —

of the full pollen cycle

V What To Do Today practical moves, in order of impact

Medication

Start an antihistamine before symptoms start

Second-generation antihistamines work best taken daily through the season, not reactively. Claritin (loratadine) and Allegra (fexofenadine) are the least drowsy; Zyrtec (cetirizine) hits harder but can make you sleepy.

Claritin → Zyrtec → Allegra →

Home

One HEPA filter, in the bedroom

Overnight exposure is where most people lose the fight. A decent HEPA unit by the bed cuts morning congestion noticeably. Keep windows closed on high-count days, even when it's tempting.

HEPA picks →

Routine

Shower when you come inside

Pollen rides your hair, clothes, and skin into the house. A five-minute rinse before bed cuts overnight symptoms as much as a second dose of meds. Wash pillowcases weekly during the worst of it.

Nasal

Flonase for the congested

Flonase (fluticasone) is the single most effective OTC move for persistent congestion, but it takes 3–5 days of daily use to build up. Start it now and it's ready when the peak arrives.

Flonase →

VI The Basics

What is allergy season?

The period when airborne pollen reaches concentrations high enough to trigger seasonal allergic rhinitis — roughly 81 million Americans. Each region's season depends on its tree, grass, and weed inventory and its climate.

When does it start and end?

It's a relay, not a single event. Each type hands off to the next:

Tree pollen — February through May, peaking in April
Grass pollen — May through July
Ragweed — August through October, ending with first frost
Mold spores — spring through fall, spiking after rain

Pollen seasons are starting earlier and lasting longer than they did thirty years ago — a direct, measurable consequence of warming temperatures.

How is pollen measured?

In grains per cubic meter of air, sampled by National Allergy Bureau stations. Tree pollen thresholds: low (0–14), moderate (15–89), high (90–1,499), very high (1,500+). Dry windy days are worst. Rain helps in the moment but feeds mold in the days that follow.

Sources

Pollen data via the Google Pollen API, refreshed daily. Counts are forecast estimates for your approximate location. Not medical advice.