Long Beach, California Pollen Count & Allergy Forecast

Long Beach pollen count and allergy forecast — tree, grass, and ragweed seasons and what’s pollinating now

Long Beach, CA · Pollen season

In September, ragweed pollen is in season in Long Beach, peaking Aug–Oct.

Based on the seasonal pollen calendar for this region.

Long Beach on the WeatherStory Allergy Index

Long Beach ranks #64 of 100 U.S. metros on the WeatherStory Allergy Index, with a modeled load index of 30 and a 274-day combined pollen season — its heaviest load is tree pollen, running 122 days.

#64of 100
Load index
30
Combined season
274 days
Heaviest load
Tree · 122 days

See the full 100 worst U.S. cities for pollen — a modeled seasonal load ranking (see methodology).

Typical now — Septemberseasonal estimate, not a live reading

Ragweed pollen typically leads in Long Beach in September, at an estimated Moderate level.

Pollen by type this season

What pollinates near Long Beach

The tree, grass, and weed species that drive Long Beach’s pollen seasons, with each plant’s typical peak.

Trees

  • Oak Quercuspeaks March–April
  • Olive Olea europaeapeaks April–May
  • Coast live oak Quercus agrifoliapeaks March–April
  • Walnut Juglanspeaks April–May
  • Ash Fraxinuspeaks February–March
  • Mulberry Moruspeaks February–March

Grasses

  • Bermuda grass Cynodon dactylonpeaks April–June
  • Wild oat Avena fatuapeaks April–May
  • Perennial ryegrass Lolium perennepeaks April–June
  • Bromegrass Bromuspeaks April–May

Weeds

  • Common ragweed Ambrosia artemisiifoliapeaks August–September
  • Russian thistle Salsola traguspeaks July–September
  • Pigweed Amaranthuspeaks August–September
  • Sagebrush Artemisiapeaks August–September

Species are the region’s common wind-pollinated plants; peak months are a seasonal estimate, not a measured count — see methodology.

Long Beach’s allergy year

Typical month-by-month pollen intensity for Long Beach, tuned to its latitude and climate region — darker means higher typical counts. The highlighted column is the current month.

JFMAMJJASOND
TreeJan–Apr
GrassMar–Jun
RagweedAug–Oct

How Long Beach compares to the U.S. average

Each colored bar is Long Beach’s typical season against the national-average window (grey). The offset is the per-city timing shift.

Tree~9 wks earlier
Grass~9 wks earlier
Ragweedabout average

“U.S. average” is the textbook tree Mar–May, grass May–Jul, ragweed Aug–Oct calendar. The shift is a phenology estimate (Hopkins’ bioclimatic law), not a measured count — see methodology.

How Long Beach’s pollen count works

The calendar above is tuned to Long Beach’s mild Mediterranean California climate, not a national average: tree pollen runs from week 1 (early January) to week 17 (late April), grass from week 10 (early March) to week 26 (late June), and ragweed from week 31 (early August) to week 43 (late October) here — a 274-day combined pollen season. Those windows are why ragweed pollen is the one in season in Long Beach right now.

No live count is wired up for Long Beach today, so the seasonal calendar above is your guide to which allergen is in season.

For the science behind Long Beach’s pollen seasons — how counts are measured, when each type peaks, and what the numbers mean — see the pollen count scale and the other pollen & allergy guides.

Frequently asked

When is pollen worst in Long Beach?
Tree pollen jumps the gun in Long Beach, opening as early as Jan–Apr while colder regions are still dormant. Grass follows Mar–Jun and ragweed closes the year Aug–Oct. The early tree start is the trap — symptoms can begin before you expect them. Currently, ragweed pollen is in season.
What's in the air in Long Beach right now?
In September, ragweed pollen is in season in Long Beach, peaking Aug–Oct. On Long Beach's mild Mediterranean California calendar the typical September level is Moderate, led by ragweed pollen — a seasonal estimate, not a live count.
Is tree or grass pollen higher in Long Beach in spring?
In spring, tree pollen leads in Long Beach — trees pollinate Jan–Apr, ahead of grass (Mar–Jun). The handoff is the tail of the tree window: tree counts taper as grass climbs, so an early-spring flare is more likely tree pollen and a late-spring one more likely grass.
What makes Long Beach's pollen season distinctive?
Long Beach sits in the mild Mediterranean California zone, which means an early start — mild winters pull tree pollen forward into late winter, ahead of a spring grass peak and a relatively contained ragweed fall. That shapes when symptoms hit and which allergen to watch.
How do I reduce pollen exposure in Long Beach?
Through Long Beach's peak windows (tree Jan–Apr, grass Mar–Jun, ragweed Aug–Oct), keep windows shut and run AC on recirculate; counts run highest on dry, warm, windy mornings, so push outdoor activity to late afternoon or just after rain, which clears pollen from the air. A HEPA purifier indoors, a saline rinse after being outside, showering before bed, and starting antihistamines a week or two before your worst local window all measurably cut symptoms.
When does the next pollen season start in Long Beach?
Tree pollen is next in Long Beach: it opens around week 1 (early January), peaks around week 7, and runs about 122 days.
What is the allergy forecast in Long Beach today?
With no live reading for Long Beach today, its allergy forecast is the seasonal estimate above: a typical September level of Moderate, led by ragweed pollen.