ArcPace: Weather for Runners

ArcPace turns the forecast into the one question a runner asks: when should I run, and how will it feel?

EVERY HOUR, SCORED Each hour of the next two days gets a run score out of 100 and a pace impact in seconds per mile or km, measured against an ordinary day. Heat and humidity slow you down; a cool morning can make you quicker. The score comes from temperature, dew point, wind and gusts, rain and altitude. Thunderstorms and freezing rain cap it outright. The UV index and WBGT heat stress (the flag system used at races) are shown alongside, described rather than scored.

YOUR BEST WINDOW AT A GLANCE Tell ArcPace when you can actually run, and it ranks those windows. Each one says what to wear and what to carry.

TEN DAYS AHEAD Each of the next ten days scored from its worst hour to its best. Open one for its best run, the day hour by hour, and what to wear.

WHAT THE WEATHER COST YOU With read-only access to Apple Health, ArcPace scores your last sixteen weeks of runs against the weather they were run in. A slow July run reads "Humidity set this pace, not you", with what it was worth on an ordinary day. A calendar of those weeks, a fitness trend with the weather taken out, and weather-adjusted bests.

ALSO • A Home Screen and Lock Screen widget with this hour's score and your best window ahead • An optional notification with tomorrow's best window • A share card for any run • Saved locations for travel planning • Imperial or metric, light or dark, Reduce Motion and Dynamic Type respected

PRIVATE BY DESIGN No account, no ads, no analytics, no server of our own. Your runs are read and kept on the phone; to score one, only its approximate place and hour go to Apple Weather. Your location goes only to the weather service: Apple Weather, or Open-Meteo as a backup.

ArcPace is free. If it earns a place in your routine, you can leave a tip from Settings.

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