Microseason 3 of 72 · January 11–15
Shortest shadows lengthen
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
Shortest shadows lengthen
The sun angles slightly higher each noon.
- SESoutheast Subtropical
Springs begin to move beneath ice
Hidden springs in the Appalachian foothills start to flow; thaw pulses move southward through groundwater.
- PNWPacific Northwest
The Lengthening
Days gain perceptibly. Afternoon light lingers five minutes longer each day. Cold still dominates, but the angle shifts.
- CACalifornia Mediterranean
Light lengthens over wet earth
Days noticeably longer. Vernal pools fill across the Coast Ranges. California poppy begins germinating in saturated soil. Ceanothus buds swell.
- MWMountain West
Springs stir beneath locked earth
Groundwater begins slow movement as subsurface temperatures rise; high peaks remain silent and white.
- MPPlains Continental
Sunlight returns to the sloped terrain
Daylight lengthens perceptibly; snow on south faces begins a slow thaw.
- SWSouthwest Desert
First warmth breaks the shallow freeze
High 60s to low 70s by midday. Nights still dip to 35-40°F. Solar angle tightens; shadows shorten. Desert takes on stronger light.
- TRTropical / Sub-Tropical
Mangrove buds swell with green
Longest sunlight hours of the year begin turning water warmer. Red mangrove prop roots glisten with renewed sap. Air stays salt-thick and warm at midday.
- AKAlaska Subarctic
Shadows lengthen after solstice
Light returns incrementally to the north; Anchorage gains 5 minutes daily while Barrow remains in near-continuous darkness.
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.