Microseason 51 of 72 · September 11–15
Hawk migration over the Hudson
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
Hawk migration over the Hudson
Broad-winged hawks kettle over the Palisades on north winds.
- SESoutheast Subtropical
Raptors trail the thermals
Hawk migration begins in earnest over the Piedmont and mountains; swallow-tailed kites cut the September sky one last time.
- PNWPacific Northwest
Raptors funnel through passes
Hawks and eagles funnel through the Cascades and coastal valleys on thermals. Hawk Ridge and other migration points pulse with southbound birds.
- CACalifornia Mediterranean
Raptor passage begins
Red-tailed hawks and golden eagles migrate south through Bay Area and mountain passes.
- MWMountain West
Hawks begin the long crossing southward
Ferruginous and Swainson's hawk migration in earnest; thermal streets above the ranges packed with raptors moving south.
- MPPlains Continental
Hawks ride thermal currents south
Raptor migration intensifies across the plains. Red-tailed hawks, Swainson's hawks, and ferruginous hawks pour over the region, riding thermals and cold fronts southbound.
- SWSouthwest Desert
Raptors ride the thermals
Cooper's hawks and broad-billed hawks gather, riding updrafts toward Mexico.
- TRTropical / Sub-Tropical
Mid-season storm lull
A brief respite emerges in the hurricane timeline; swell diminishes and easterly waves pause momentarily.
- AKAlaska Subarctic
Geese arrow toward open water
Waterfowl migration peaks; thousands of brant, Canada geese, and tundra swans push southward in formation.
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.