Allergy season 2027: when pollen starts where you live
The 2027 pollen season starts before 2026 ends. Mountain cedar in central Texas begins in December, and Florida's oaks can follow before New Year. Here is when each pollen usually starts and peaks in each US region, what moves the dates, and how to know when yours opens.
The short answer
- Earliest: mountain cedar in central Texas, December 2026 to February 2027.
- January: trees start in Florida, California and the Pacific Northwest (alder).
- February: trees start in the Southeast, Texas (oak), the desert Southwest and the Mountain West.
- March: trees start in the Northeast and Midwest.
- May to July: grass season almost everywhere, peaking in June.
- Mid-August to the first frost: ragweed, heaviest in the Midwest and the East.
Expected 2027 pollen calendar by region
These are the typical months. A single year can start two or three weeks early or late.
| Region | Tree | Grass | Ragweed / weeds |
|---|---|---|---|
| Northeast | Mar – May | late May – Jul | mid-Aug – first frost |
| Southeast | Feb – May | Apr – Sep | Aug – Nov |
| Florida | Dec – Apr | most of the year | Aug – Nov |
| Texas and South Central | Dec – Apr (cedar, then oak) | Apr – Oct | Aug – Nov |
| Midwest | Mar – May | May – Jul | mid-Aug – first frost |
| Mountain West | Feb – May | May – Jul | Aug – Oct (sage, Russian thistle) |
| Desert Southwest | Feb – Apr | Apr – Oct | Aug – Nov |
| California | Jan – May | Mar – Jul | Jun – Oct |
| Pacific Northwest | Jan – May | May – Jul | Jul – Sep (light) |
See today's level and the local calendar for 38 US cities.
Will 2027 be a bad year?
Nobody can tell you that yet with any accuracy, and you should be careful with anyone who claims to. Pollen forecasts are useful about five days ahead. What decides a season is the weather that has not happened yet:
- A warm late winter starts the trees early and makes the tree season longer.
- A wet spring grows more grass, so the June grass peak is stronger.
- A late first frost lets ragweed run longer into the fall.
- Rain on the day washes pollen out of the air. Dry, windy days carry it far.
Over the long term, US pollen seasons have been getting longer as the frost-free season grows. Expect the edges of each season, not only the peak, to matter.
Why the start date matters most
Allergy medicines such as nasal steroid sprays work best when you start them before your season, not after symptoms begin. Doctors often say to start about two weeks early. So the most useful thing to know is not "how bad will 2027 be" but "when does my pollen come back".
Not sure which pollen is yours? Read which pollen am I allergic to.
Getting warned before your season opens
Pollenary watches each pollen type on its own. When a type has been absent for three weeks and comes back near you, it sends a season-start alert, even while the level is still low. After that it sends one push each morning when that pollen reaches your level, with the plants named. It is free, with no account and no location tracking.
Season months are typical patterns, not a forecast for a specific day. Pollenary is not a medical device and does not diagnose or treat any condition. Talk to a doctor about your allergies.