Microseason 18 of 72 · March 26–31
Forsythia opens along the fences
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
Forsythia opens along the fences
Yellow forsythia blazes against bare wood and brick.
- SESoutheast Subtropical
Redbud cascades over the thaw
Eastern redbud blossoms explode in waves of magenta and pink. Spring pulses hard through the Coastal Plain.
- PNWPacific Northwest
Salmonberry First Bloom
Salmonberry shrubs open pale pink and coral flowers on streamside slopes; Oregon grape begins blooming in colonies, low and golden through the understory.
- CACalifornia Mediterranean
California poppy ablaze
Golden poppies carpet hillsides from coast to Central Valley. Warm afternoons pull thermals that carry red-tailed hawks and turkey vultures.
- MWMountain West
Aspen catkins burst in clusters
Quaking aspen catkins unfurl throughout the Wasatch and Front Range valleys. Marmots and pikas emerge to feed on fresh tips.
- MPPlains Continental
First Green Breaks Through Brown Earth
Early wildflower buds swell along prairie slopes; spring ephemeral flush begins across the tallgrass.
- SWSouthwest Desert
Saguaro crowns with flowers
Saguaro flowers open white-and-golden in pre-dawn; hummingbirds swarm blooms.
- TRTropical / Sub-Tropical
Coral blooms begin
Warmer water and longer days trigger first corals toward spawning, visible as pale mucus clouds at dusk on reefs.
- AKAlaska Subarctic
Cottonwoods blush and swell
Balsam poplar and cottonwood buds swell with sap; pussy willows appear. River ice remains thick but rivers surge underneath.
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.