What is the pollen count in Half Moon Bay today?

Today's pollen levels in Half Moon Bay: Tree pollen is None, Grass pollen is Very High, Weed pollen is None. Grass pollen is the dominant type right now, driven by Grass.

What does a Very High pollen count mean in Half Moon Bay?

A Very High pollen count means concentrations are at their peak. Nearly all allergy sufferers will experience noticeable symptoms, and limiting outdoor exposure is recommended.

What are the main allergy triggers in Half Moon Bay right now?

The primary allergy triggers in Half Moon Bay today are Grass (Grass). These pollen types are at elevated levels and are most likely to cause symptoms for sensitive individuals.

What should allergy sufferers do when pollen is Very High in Half Moon Bay?

When pollen is Very High in Half Moon Bay, limit outdoor time during midday when concentrations peak. Keep windows closed, shower after being outside, and consider taking antihistamines before symptoms start.

Does weather affect pollen levels in Half Moon Bay?

Yes, weather directly affects pollen levels in Half Moon Bay. Wind spreads pollen farther, rain washes it from the air, and humidity can either trap or disperse particles. Higher humidity today (87%) may help keep some pollen grounded.

Half Moon Bay, CA Pollen Count Today

Name: Pollen Data for Half Moon Bay
Creator: MyPollenPal
Keywords: pollen, air quality, allergies, forecast

Live pollen forecast and air quality for Half Moon Bay, California

📍 Half Moon Bay, CAToday · May 31

2/10

Breathability™ Score

Challenging day - reduce exposure during peak pollen times.

🌳Tree Pollen

None

🌱Grass Pollen

Very High

🌿Weed Pollen

None

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Today's Pollen Levels in Half Moon Bay

Grass pollen is the dominant contributor today in Half Moon Bay, with levels reaching Very High. Other pollen types are not a significant factor right now. With a Breathability™ Score of 2, today may feel like a tougher allergy day.

Breathability™ Score is 2/10
Tree pollen is None, led by Alder and Birch
Grass pollen is Very High, led by Grass
Weed pollen is None, led by Ragweed and Mugwort
Air quality is Good today

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How Today's Pollen May Affect You

Mild allergy sufferers

You may feel symptoms sooner today. Grass pollen is elevated and air quality is Good, so lean toward shorter outings and cleaner indoor air.

Moderate allergy sufferers

Today may feel challenging. Limit prolonged outdoor time, keep indoor air filtered, and prioritize lower-exposure times of day.

Severe allergy sufferers

This may be a high-burden day. Minimize outdoor exposure where possible and focus on indoor spaces with filtered air.

5-Day Pollen Forecast

Today

May 30

Overall: Very High

Tree: None

Grass: Very High

Weed: None

Wind: 14 mph

Rain: 86% (may wash pollen out)

Humidity: 90%

Sun

May 31

Overall: Very High

Tree: None

Grass: Very High

Weed: None

Wind: 11 mph

Rain: 0%

Humidity: 78%

Mon

Jun 1

Overall: Very High

Tree: None

Grass: Very High

Weed: None

Wind: 9 mph

Rain: 0%

Humidity: 79%

Tue

Jun 2

Overall: Very High

Tree: None

Grass: Very High

Weed: None

Wind: 11 mph

Rain: 0%

Humidity: 83%

Wed

Jun 3

Overall: Very High

Tree: None

Grass: Very High

Weed: None

Wind: 16 mph (may spread pollen)

Rain: 0%

Humidity: 77%

Tree Pollen in Half Moon Bay Today

Tree pollen in Half Moon Bay is None today. Tree pollen season typically runs from early spring through late May, peaking when deciduous trees release their pollen. On low days like today, outdoor activities are generally comfortable for most allergy sufferers.

Species Breakdown

Alder0 grains/m³

Birch0 grains/m³

Hazel0 grains/m³

Oak0 grains/m³

Grass Pollen in Half Moon Bay Today

Grass pollen in Half Moon Bay is Very High today, reaching 432.12 grains/m³. Grass is currently elevated. People with grass pollen sensitivity may notice nasal congestion and itchy eyes, especially during outdoor activities.

Common Symptoms

Itchy nose and eyes
Sneezing fits
Nasal congestion
Watery eyes
Coughing or wheezing for sensitive individuals

Species Breakdown

Grass432.12 grains/m³

Weed Pollen in Half Moon Bay Today

Weed pollen in Half Moon Bay is None today. Weed pollen season runs from late summer into fall (August through October), with ragweed as the primary trigger for most allergy sufferers. Current levels are low enough that most people should feel comfortable outdoors.

Species Breakdown

Ragweed0 grains/m³

Mugwort0 grains/m³

Air Quality in Half Moon Bay Today

🌬️

Air Quality

Good

Air Pollutant Breakdown

PM2.5Moderate

14 µg/m³

Tiny particles smaller than 2.5 micrometers that can reach deep into your lungs and bloodstream. High levels can affect breathing and heart health.

PM10Good

21 µg/m³

Larger particles up to 10 micrometers, like dust or pollen. They can irritate your airways and worsen allergies or asthma.

Ozone (O3)Good

69 µg/m³

Elevated levels irritate airways and can worsen asthma symptoms.

Nitrogen Dioxide (NO2)Good

8.9 µg/m³

A respiratory irritant from vehicle exhaust that can trigger inflammation in sensitive airways.

Sulfur Dioxide (SO2)Good

1.5 µg/m³

Even brief exposure can tighten airways, especially for people with asthma.

Carbon Monoxide (CO)Good

127.8 µg/m³

High levels reduce oxygen delivery in the body, compounding breathing difficulty on high-pollen days.

Weather in Half Moon Bay Today

☀️

Weather

52°F

Clear

Humidity

87%

Wind

10 mph NW

Feels Like

51°F

Pressure

1019 mb

Frequently Asked Questions

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