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Weather apps show forecasts. PrimeWindow shows opportunities.

Set the wind conditions you actually care about. PrimeWindow tracks your spots and sends a notification when a usable window appears.

Not another weather app. Built for clear calls, not more chart checking.

  • Define your conditions once.
  • PrimeWindow watches your spots.
  • Get notified when a window opens.

No more refreshing forecasts all day to catch a two-hour window.

Read: The problem with weather apps

PrimeWindow alert

New Prime Window

Low winds at South Bay in 2 days.

Prime Window

06:40-08:10

South Bay

Go • 82%
Window timelineiPhone
Go
Marginal
No-go

The problem

Forecast data is not decision clarity.

Raw data is useful, but it still leaves the hard part with you: deciding if it is actually on.

The reframe

Weather apps show forecasts. PrimeWindow shows windows.

You define your rules, PrimeWindow watches the forecast, and you get notified when the match appears.

Green = GoOrange = MarginalRed = No-go

Higher confidence

Lower confidence

Set your conditions

Define wind direction, speed, gust limits, rain, and daylight once.

PrimeWindow watches

It keeps checking your spots in the background across upcoming forecast windows.

You get the signal

A notification appears when your conditions line up and the window looks usable.

Built for wind-dependent sports

Built for people whose plans depend on the wind.

Paragliders

Know when your hill is actually on.

Paramotor pilots

Catch usable wind windows without constant checking.

Wind-dependent athletes

Set your thresholds and get a clear signal.

Why it matters

More clarity. Less checking.

PrimeWindow does not try to remove uncertainty. It helps you spend less time interpreting charts and more time acting when a real opportunity appears.

  • Less time spent refreshing forecasts.
  • More confidence about when it is worth going.
  • Fewer missed short windows.
  • Clearer calls with less second-guessing.

Decision view

Before

Check app 1
Check app 2
Compare models again

After

PrimeWindow alert: Go window found

Why we built this

If you want the full context behind PrimeWindow, read the founder note.

Read: The Problem With Weather Apps

Built for iPhone

On your phone. Right when it matters.

PrimeWindow is mobile-first and notification-led. While you are at work, travelling, or doing normal life, it keeps watch and only interrupts when your window appears.

No need to refresh forecasts all day.

PrimeWindow alertiPhone

Mam Tor

Tue, 14:00-17:00

Green • Go

Light NW · low gusts · no rain

State

Green = Go

Orange = Marginal

Red = No-go

Early access

Join the waitlist

PrimeWindow is pre-launch for iPhone. Leave your email to get early access when testing opens.

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