Barometer: Pressure & Forecast

Read the pressure, and know what the weather is about to do. Works on phones with no pressure sensor.

A falling barometer is the oldest weather warning there is. Three hours of pressure says more about tonight than a look at the sky does, and it is why sailors, pilots and gardeners have read one for two centuries. This app puts that dial in your pocket and does the reading for you.

Plenty of people feel a pressure drop before they see it. If headaches or aching joints track the weather for you, the chart and the storm alert give you the number behind the feeling.

Roughly half of all Android phones have no pressure sensor. On those, Barometer reads the nearest reporting weather station instead. The measurement is real, it is just taken somewhere else. On the first launch it pulls a week of that station's history, so the chart and the forecast work in the first minute instead of in three hours.

KEY FEATURES

Pressure now
Sea-level pressure on an aneroid dial with a set hand, like the wall barometer it is modelled on. Read it in hPa, inHg or mmHg. Phones with a sensor also see the raw value at your own altitude.

12-hour forecast
The Zambretti forecaster turns the pressure, its three-hour trend and the season into one plain sentence about the next twelve hours. It is the method behind the Fair, Change and Rain printed on every wall barometer, and the app shows you which numbers went into it. Your reading is measured against what is normal at your nearest station, so a coastal summer does not come out as permanent rain.

Three-hour trend
Rising, steady or falling, with the exact change over three hours. Every sample is reduced to sea level using your altitude, so walking up a hill never looks like a storm.

Seven days of history
A pressure chart over 24 hours, 48 hours or a week, with the high, the low and the span. On a phone with no sensor the whole week arrives on the first launch.

Storm alert
A notification when the pressure falls fast enough to matter. The threshold is twice the marine rapid-change rate, so it fires for weather and not for a lift ride.

Home screen widget
The pressure now and what it means for the next twelve hours, without opening the app. It refreshes on its own, and every reading carries the time it was taken rather than the time you looked at it.

Make it yours
Five themes including a true black one for AMOLED screens, three pressure units, and fifteen languages.

WHO READS A BAROMETER

Anglers and sailors, because fish and swell both follow the pressure. Pilots and paragliders, who set an altimeter against it before every flight. Hikers, who watch it turn on a ridge. Gardeners and beekeepers, who plan a day around it. And anyone whose head or joints know a front is coming before the forecast does.

FREE, AND FREE OF THE USUAL
No ads. No subscription. No account. No in-app purchases. Everything on this page is in the app from the first launch.

PRIVACY
No background location tracking, and your position is never sent anywhere. When your phone has no pressure sensor, the app picks the nearest weather station on the device from a list it ships with, then asks for that station by its four-letter code. Nothing else leaves your phone.

WHAT A BAROMETER IS NOT
It forecasts from one number in one place. It knows nothing about a front coming over the horizon and it does not replace a weather service. What it does is tell you which way the air is moving right where you are standing, and on a phone with a sensor it does that with no signal at all.