Boost Weather: Air Density

Density altitude, air density, and intake charge temp for your car, read from Apple Weather where you are and graded Green, Yellow, or Red against your own thresholds. One read on the air before you drive. Boost Weather takes four inputs, temperature, dew point, station pressure, and elevation, and computes eleven air values on your phone: density altitude, relative air density, air density, dew point, humidity, specific humidity, station pressure, altimeter, and the correction factor a dyno would apply. Then it grades them against a car profile and gives one verdict, Green, Yellow, or Red, with the reason on the card. Green comes in three reads, so a cool morning and a warm afternoon no longer look the same: Thick air when the air is dense, the temperature in a word when every line is clear, and the note that trims it, such as Warm air or Very humid, when one does. The verdict describes the air, never the car. CAR PROFILES Start from two templates, one for forced induction and one for naturally aspirated, and edit every line: the yellow and red temperature bands, dew point and humidity lines, a tire floor, and for a boosted car the charge temperature offset and the ideal, ceiling, and knock lines. The editor lists typical offsets by intercooler type and lines by fuel, so you can set yours without guessing. OFFSETS The air over sunlit pavement reads warmer than a weather station's number taken over grass. Type what your dash shows and the difference becomes the ambient offset, with a separate highway line for Drive mode. Drive mode watches your GPS speed while the app is open and switches to the highway line above the speed you set. It stops the moment the app leaves the screen, never tracks in the background, and stores or sends nothing. WHY THIS READ Tap the question mark on the verdict to see every check your profile ran: your value against each threshold, what fired, and why. On a device with Apple Intelligence turned on, the page opens with a short analysis written on your device from those checks. It never changes the verdict, and you can turn it off in Settings. SURFACE When rain, snow, ice, or a storm is falling where you read the air, an orange pill beside the verdict says so: Wet surface, Snow, Ice risk, or Storm. Tap through to see what it means for grip and the hour it should clear. FORECAST A seven-day card under the verdict, one bar per day from the low to the high, colored by what the air will read at the day's warmest hour for your profile. Open any day for the hours. APPLE WATCH AND WIDGETS The watch app shows the verdict, the tiles, the forecast, a profile picker, and one-tap snapshots. Home Screen and Lock Screen widgets and watch complications each pick a metric, so a face can hold several. MORE - Snapshots you can share with a tuner as a one-line air read, as text, or as JSON. - Manual mode for entering all four values yourself, always badged. - Custom locations: save a track, a city, or a ZIP code and read the air there. - Imperial or metric, your choice. - Works offline: the last reading stays visible with its age. - No account, no sign-in, no ads, no analytics. Location is used only to fetch the weather where you are. Read the air. Then go drive. Weather data provided by Apple Weather. Terms of use: https://joneslabs.dev/terms#boostwx