Microseason 50 of 72 · September 6–10
Asters purple the roadsides
A five-day window of the year, read through nine North American climate regions.
Same week, nine climates
A microseason names a five-day window of the solar year. What that window actually looks like on the ground depends on where you are. Below, the same calendar window read through each of nine North American climate regions.
- NENortheast Continental
Asters purple the roadsides
New England asters bloom in violet waves along neglected edges.
- SESoutheast Subtropical
Dew beads on resurrection fern
Morning dew glistens on every leaf and web; resurrection fern unfurls its fronds as humidity lingers in the Lowcountry.
- PNWPacific Northwest
Dew settles thick
Spider webs jewel the meadows at dawn, heavy with moisture. Grass glitters. The shift from dry to damp accelerates.
- CACalifornia Mediterranean
Dew on drying grasses
Early morning dew still beads on bleached annual grass heads. Autumn's first whisper.
- MWMountain West
Dew crystallizes on high grass at dawn
September mornings arrive with ice crystals on alpine meadows; the shift from wet-summers-on-the-peaks is complete.
- MPPlains Continental
Purple asters rise on the prairie
Morning dew heavy again as temperatures drop. Asters bloom purple along roadsides and prairie margins, feeding late butterflies. First freeze still weeks away.
- SWSouthwest Desert
Dew returns to the flats
Morning moisture glistens on brittlebush and creosote after cool nights.
- TRTropical / Sub-Tropical
Wet-season rains peak
Afternoon convection reaches its climax; nearly every day brings heavy tropical showers that cool the landscape.
- AKAlaska Subarctic
Night reclaims its ancient dominion
Equinox arrives; twelve hours of darkness, twelve of light balance perfectly before winter's grip tightens.
About the 72-microseason calendar
A microseason is a five-day window of the solar year — long enough to notice something change, short enough that the change is specific. The year holds seventy-two of them, six per month, ordered by what the natural world is doing rather than what the clock says. Almanac calendars like this are an old American habit, kept by farmers, gardeners, and birders for centuries; Weather Story collects them into a single reference.
Each microseason is read through nine North American climate regions. The phenological events that mark a five-day window vary with ecology — the strawberries that open in the Northeast might coincide with the first magnolias dropping in the Southeast and the salmonberry blossoms unfurling in the Pacific Northwest. Same week, nine ecologies, nine readings.