# Whumpf

Every forecast you check before dawn, on one screen. Consumer iOS app. 2026. Role: Sole developer — web version, native port, and backend.

Published 2026-07-23 · Updated 2026-09-30 · Author: Kai Myers, K.AI Consulting, Anchorage, Alaska
Canonical page: https://kaiconsulting.ai/work/whumpf

## In one sentence

Backcountry travellers in Southcentral Alaska check several avalanche centers before leaving the house, each on its own site, each formatted differently. Whumpf (formerly Avy Comparison) puts them side by side with the weather data that explains them.

## The problem

Deciding where to go in the morning means reading forecasts from more than one avalanche center — Chugach National Forest, Hatcher Pass, sometimes Valdez — and each publishes on its own site in its own format. Comparing them is manual, and the weather station data that would tell you whether the forecast still holds lives somewhere else entirely.

It is also the wrong task to be doing on a phone in a trailhead parking lot with one bar of service.

## What was built

A comparison view that puts every zone you care about on one screen, across avalanche centers, with the danger rose, the current avalanche problems, and their likelihood readable at a glance.

Zone detail that carries today and tomorrow's ratings by elevation band, the forecaster's bottom line, the full problem breakdown with aspects and elevations, and a link through to the original forecast — the app repackages public forecasts, it does not replace reading them.

Live SNOTEL station observations and NWS mountain weather folded in alongside the forecast, including temperature and wind sparklines, so the forecast can be checked against what the snowpack is actually doing.

An offline cache that keeps the last snapshot on the device, so the forecast is still there when service is not — plus observation submission straight into the National Avalanche Center's public API.

## Outcome

- Native iPhone app shipped through EAS Build to TestFlight
- Covers Alaska centers — Chugach, Hatcher Pass, Valdez, Cordova, Eastern Alaska Range, Coastal, Haines — alongside centers in the lower 48
- Shares one Supabase backend with the web version; the native port needed no backend changes
- Forecasts stay readable offline after the last sync

## Stack

Expo SDK 54, React Native, React 19, Expo Router, NativeWind, Supabase Edge Functions, TanStack Query, react-native-svg

Source: https://github.com/Kaiguy277/AvyComparisonApp