Storm Window

Activity-aware outdoor risk planning, at a glance.

Know when it is safest to walk, run, ride, work, boat, swim, or head outside as environmental risks change throughout the day.

Download on the App Store

Location powers local guidance, maps, widgets, and alerts. Backend features use a coarsened forecast grid, not precise GPS. See the Privacy Policy.

Storm Window isn’t another weather app. It answers one practical question: when should I go? Every hour is scored for outdoor risk: lightning, storms, wind, heat stress, cold, air quality, official active alerts, and activity-relevant hazards. Pro turns that scoring into a best window sized to how long you plan to be out, with a quality score and a start-by time. Then it tells you when a low-risk window closes and when the next safe window opens.

Storm Window onboarding screen explaining how the app works — Quick setup for location, activity, and planning style.

Storm Window Now tab in light mode showing the current outdoor risk and best-time guidance — The Now view answers whether this is a good time to go.

Storm Window Now tab in dark mode showing the current outdoor risk and best-time guidance — Dark mode keeps the same risk verdict and timing guidance.

Storm Window Forecast tab showing the hourly risk chart and forecast details — Hourly charts show how risk changes through the day.

Storm Window Plans tab showing monitored outdoor plans and forecast guidance — Plans monitor future outings as conditions shift.

Storm Window Lightning Map showing recent storm and lightning context near a location — Lightning Map adds nearby storm context when timing matters.

Storm Window Wind Map showing wind context and map-based forecast guidance — Wind Map shows speed, gust, direction, and Pro wind flow.

Storm Window iOS widget showing the next safe window and compact risk chart — Widgets keep the next safe window on your home screen.

Storm Window Apple Watch app showing the current outdoor risk and daily risk chart — Apple Watch shows current risk and the day ahead.

Storm Window Apple Watch app showing watch-local forecast details and risk chart — Watch-local details help you check conditions away from iPhone.

How it works

Read the day by risk

The home screen turns the next few days into hourly risk charts for Today, Tomorrow, and the next useful outlook day. Colors move from low risk to caution, unsafe, and dangerous, with advisory overlays when official alerts are more cautious than local conditions.

Understand what is driving it

Factors & Conditions separates the signals shaping the verdict from the context that helps you plan. Wind, heat, storms, air quality, marine conditions, temperature, precipitation, sky, UV, and comfort are organized into focused trend views.

Find the best time to go

Pro’s Best Time Today finds a window sized to your activity and duration, gives it a quality score, and shows when you should start by. Headlines stay plain: low-risk until a specific time, or safe window opening later.

Open maps when context matters

Lightning and Wind maps add situational context when nearby motion matters. Wind Flow is available to Pro users in supported U.S. HRRR coverage areas, while Storm Window’s point forecast and activity thresholds remain the safety source of truth.

Plan by activity and place

Activity-aware details keep the app focused on what matters for that outing. A lake house can watch golf and swimming separately, while beach, water, work, fitness, and family profiles surface different hazards.

Keep the answer close

Widgets, the Apple Watch app and complications, Outdoor Sessions, notifications, and Pro+ guidance keep current risk, time remaining, future Plans, and forecast changes visible without digging through the app.

Who it’s for

Storm Window is built for people who make outdoor decisions around timing, exposure, and changing conditions.

Walkers and runners
Cyclists
Golfers
Boaters and paddlers
Swimmers
Beach days
Parents with strollers
Babywearing outings
Outdoor workers
Coaches and field sports
Hikers
Fishing trips

Storm Window Pro

Free covers Everyday, walking, running, cycling, stroller, and babywearing profiles, with up to 2 watched activities at one saved location. Pro is for people who plan across more activities, places, and devices.

Best Time Today Finds a window sized to your activity and duration, with quality scoring, start-by guidance, and activity comparison.
More activity depth Adds hiking, golf, beach, pool, swimming, boating, paddling, fishing, outdoor work, sports, tactical training, and custom profiles.
Full condition analysis Unlocks full Factors & Conditions charts, per-hour details, driest-stretch highlights, and Risk Profile radar charts.
More places and surfaces Adds up to 10 additional saved locations, up to 5 watched activities per location, location nicknames, widgets, complications, and Watch-local controls.
Live outdoor context Outdoor Session keeps current risk and remaining time visible on iPhone, Apple Watch, Lock Screen, and Dynamic Island.
Advanced map context Animated Wind Flow is available in supported U.S. HRRR coverage areas, alongside contextual other-location alerts.

Storm Window Pro+

Pro+ adds proactive monitoring, richer planning, and Advisor explanations for people who want Storm Window to keep watching while they are not staring at the forecast.

More monitoring capacity Watch up to 25 additional saved locations on top of Follow My Location, with unlimited watched activities per saved location.
Proactive alerts Get window-change, best-window, next-window, briefing, and Plan forecast changed alerts when enabled.
Future Plans Pin fixed or flexible outings beyond the normal 72-hour view, then track whether the outlook is improving, worsening, or shifting.
Advisor guidance Ask why an hour was rated that way, why a window was chosen, whether you should go, what changed, or what the 3-day outlook means.
Sharing and automation Create shareable low-risk-window snapshots and Plan cards, with Siri, Shortcuts, and Control Center access to Plan status.
Same deterministic source of truth Advisor explanations describe Storm Window’s calculated guidance; they do not replace the risk engine. Devices without Apple Intelligence use built-in fallback explanations.

Download on the App Store

QR code linking to Storm Window on the App Store — Scan to install

Your location powers local guidance and alert timing. Backend features use a coarsened forecast grid, not precise GPS. See the Privacy Policy.

Legal & Support

Quick Start A visual 3-5 minute tour of the Storm Window workflow.
User Guide Task-oriented help for risk, activities, Forecast, Best Time Today, and Start by.
Support Help, FAQs, and how to get in touch.
Capabilities Free, Pro, and Pro+ comparison plus risk-factor roles.
Apple Watch Watch app, complications, and location/activity behavior.
Threshold Sources References behind Storm Window’s activity safety thresholds.
Privacy Policy How Storm Window handles your data.
Terms of Use Disclaimers, liability limits, and assumption of risk.
License Agreement Apple’s Standard End User License Agreement (EULA).
Contact Support Questions, feedback, or a bug to report? Email support@StormWindow.SiPhy.com.

Not a safety device

Storm Window provides forecast guidance and weather-risk context only. It is not a certified lightning safety system, emergency alert system, medical app, or guarantee of safe conditions. Do not wait for Storm Window: when thunder roars, go indoors.