Henderson pollen forecast - today, tomorrow and the week ahead
Pollen Today
Today (20 September) pollen in Henderson is high; grass and ragweed are high; mugwort is low.
Pollen Tomorrow
Tomorrow (21 September 2026) mugwort remains low, ragweed remains high, grass declining.
7-Day Trend
Over the next week grass, mugwort, and ragweed will decrease.
Explore Forecasts
Air Quality
Pollen in Other Cities
Air Quality in Other Cities
Get More in Our App
Local pollen and air quality forecasts, interactive pollen maps and route profiles
Features and forecast availability vary by region.
Pollen Risk
Today - 20 September
| Pollen species | Level | Value |
|---|---|---|
| Alder (Alnus) | None | 0/100 |
| Birch (Betula) | None | 0/100 |
| Hazel (Corylus) | None | 0/100 |
| Cypress (Cupressaceae) | None | 0/100 |
| Grass (Poaceae) | High | 55/100 |
| Willow (Salicaceae) | None | 0/100 |
| Mugwort (Artemisia) | Low | 21/100 |
| Ragweed (Ambrosia) | High | 70/100 |
Tomorrow - 21 September
| Pollen species | Level | Value | 7-Day Trend |
|---|---|---|---|
| Alder (Alnus) | None | 0/100 | — |
| Birch (Betula) | None | 0/100 | — |
| Hazel (Corylus) | None | 0/100 | — |
| Cypress (Cupressaceae) | None | 0/100 | — |
| Grass (Poaceae) | Moderate | 50/100 | |
| Willow (Salicaceae) | None | 0/100 | — |
| Mugwort (Artemisia) | Low | 17/100 | |
| Ragweed (Ambrosia) | High | 70/100 |
Local Environmental Conditions
Henderson's desert setting in the Las Vegas Valley means introduced olive, mulberry, and cypress trees planted across parks and residential streets are the main allergenic pollen sources, with exposure varying between these irrigated green areas and the more arid urban core. Surrounding Mojave Desert scrub and grassland contribute seasonal shrub and grass pollen under prevailing winds across the valley.
Henderson's pollen season is dominated by introduced olive and mulberry from February through April, producing intense early-season tree pollen. Native Mojave Desert species contribute seasonal shrub pollen, while introduced grasses add spring exposure. The long, hot, dry Las Vegas Valley summer largely suppresses mid-season pollen. The flat desert basin concentrates pollen under calm spring conditions, with exposure almost entirely from irrigated urban plantings.
Get pollen & AQ on Strava
Follow your environmental exposure and performance with the free Airmine-Strava integration. See your pollen and air quality exposure for every Strava activity.
Resource Hub
Frequently Asked Questions About Pollen in Nevada
Is pollen high in Henderson right now?
On 20 September 2026, overall pollen levels in Henderson are high. Ambrosia is the main contributor to airborne pollen, while grass and artemisia remain at lower levels
Will pollen levels change in Henderson tomorrow?
On 21 September 2026, pollen conditions in Henderson will be different from today, with ambrosia at high levels, artemisia at low levels and grass continuing to decline
Is pollen expected to decrease in Henderson this week?
According to the five-day outlook, ambrosia, artemisia, and grass pollen levels are expected to gradually decrease, suggesting improving conditions later in the week.
Which pollen types are currently active in Henderson?
On 20 September 2026, Ambrosia is the dominant pollen source in Henderson. grass and artemisia are also present but at lower levels.
When is pollen season in Henderson?
How often is the Henderson pollen forecast updated?
The Henderson pollen forecast is updated four times daily. See the timestamp below for the most recent update.
Does pollen in Henderson come from nearby or far away?
Studies show that most pollen exposure (often 70–90%) comes from nearby sources, such as local trees and vegetation. A good pollen forecast therefore depends on accurately representing local vegetation. Pollen can travel long distances, but this usually matters only early in the season or during specific wind events.
Are pollen levels in Henderson based on measurements or forecasts?
Pollen data is often misunderstood. Most "pollen levels" are not real-time measurements, but forecasts.
Direct pollen measurements are typically delayed by 1-2 days because they require manual analysis. To show current conditions in Henderson, modern forecasts combine recent measurements, weather data, and information about local vegetation.
This allows us to estimate pollen levels for today and the coming days, not just report the past.
Airmine’s atmospheric monitoring platform was developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team, using satellite and Earth observation technologies to improve emissions monitoring.
Understanding the Scale
The 0–100 scores represent risk levels, not direct measurements of pollen or air pollutant concentrations. Higher scores indicate higher risk. Pollen and air quality use different thresholds.
Pollen
| None | 0 | No or negligible risk of exposure. Pollen/mold exposure is expected to be minimal. |
| Low | 0-25 | Low risk of exposure. Small amounts of pollen or mold spores may be present. |
| Moderate | 25-50 | Moderate risk of exposure. Pollen/mold exposure is expected to be noticeable. |
| High | 50-75 | High risk of exposure. Elevated pollen/mold exposure is expected. |
| Very High | 75-100 | Very high risk of exposure. Pollen/mold exposure is expected to be at or near its highest levels. |
Get More in the Airmine Pollen app
Get 15-day pollen forecasts with morning, afternoon and evening detail, plus 5-day air quality forecasts. Explore interactive pollen risk maps, estimated pollen season start, route profiles and a symptoms diary.
Features and forecast availability vary by region. Currently covering Europe, the contiguous US, southern Canada, South Africa, Australia, Indonesia (Java & Bali), Brazil, Paraguay, Uruguay and the Buenos Aires area.
Developed with support from the European Space Agency (ESA) Business Applications and Space Solutions (BASS).
