July 21, 2016

Innovative New Weather App Observes Pressure and Provides Useful Weather/Elevation Information

  • Want to make an important contribution to weather prediction?
  • Possess a smartphone app that gives you state-of-the-art weather information?
  • Use an app that will provide an accurate elevation while hiking or other activities?
  • An app that works on many Android smartphones, is highly rated, and is free?
Well, my group at the University of Washington has one for you: uWx
An app you can download today at the Google Play store.  The app website is here.

Billions of surface pressures each hour

As described in some of my previous blogs (here and here), at the University of Washington we have a project directed towards answering a central question:

Can pressure observations from millions of smartphones revolutionize weather forecasting?

By the end of the year over a billion smartphones with relatively high quality pressure sensors will be in use, producing a surface observing network of unparalleled density and number.  

Can this data be collected and then used in numerical weather prediction, resulting in substantially improved forecasts?

Why this app?

Our initial tests applying smartphone observations used pressures collected by a small firm called PressureNet.  The initial results were promising. But PressureNet has gone out of business.  We approached Google and Apple to assist us, but so far they are not interested in improving weather prediction. We are talking with a major weather app about including the necessary code, but that hasn't been fruitful yet.

Importantly, we need a smartphone platform that will allow us to test a variety of approaches to securing pressures (e.g., how we calibrate the pressures, frequency of observations, knowing when the phone is moving, etc.)    And we want to try using the smartphone pressures over places like the Pacific Northwest, to demonstrate value.

Our conclusion:   we needed to build our own app to give us the flexibility required to push the envelope.  And it would have to be so fun to use and valuable that large numbers of folks would want to download it.

Thus was born uWx!  The author of this app is a very talented UW graduate student, Conor McNicholas.

Why Should You Try uWx?

Besides collecting and calibration smartphone pressures, uWx offers an amazing range of capabilities:

1.  The latest weather observations at your current location (or any other)--see screenshots above.

2.  The climatology of any location.

3.  Five day forecasts at your current or other location.  Including forecast maps.

4.  High resolution radar and satellite imagery (high-resolution radar imagery is normally not available in free weather apps).

5.   You can view the pressure measured by your smartphone and see a real-time plot of its variation (lots of fun moving the phone up and day and seeing the pressure change!)

6.  Want the best altimeter around?   This app tells you exactly how high you are, and even plots your progress over time.  Hikers should love it.  And the heights are MUCH better than you will get with GPS.


I have only touched upon a few of the capabilities of this app, which currently is only available for Android smartphones.  It has been designed to minimize battery demands.  Currently, there is a small group of folks testing it (about 500), but we need to increase that number dramatically.  And many of the features of this phone work anywhere around the world.  During the initial few weeks there will be only U.S. downloads, but full international access will be available soon.

If you want to try it, please go to the Google PlayStore and download it.

If you are in a position to encourage Google or Apple to get interested in helping weather prediction, send me an email (or leave a comment on this blog).  They could greatly contribute to better weather prediction if they wanted.  Hardware manufacturers (e.g., Samsung, Xiaomi, Lenova, etc.) could do the same.

Although our new app is completely free, contributions (deductible) will help enhance our research efforts are very welcome.  Click here.  We are doing this on shoe-string budget and additional funds would really help (bringing in more help).


  1. I installed it right away the first time you mentioned it.
    It's a great App and I encourage all of you to install it.
    Hopefully your phone has the sensors such as my Samsung S4.

  2. I'm not sure if this is helpful but Netatmo has a world wide map of all of its connected devices for weather. They have an SDK as well that might be useful. https://www.netatmo.com/en-US/weathermap

    1. C'mon Google, don't be evil. Support better weather prediction, and this line of research that Dr. Mass is spearheading

  3. Why does it not allow Canadians (Victoria BC) to download?

  4. Is there not yet an iPhone app version?

  5. "Currently our server is down for maintenance "

    But otherwise it seems to work on my BlackBerry BB10 phone

  6. According to the app, it says my droid turbo 2 doesn't have a barometer. According to google, it does. Do I have a setting I need to enable?

  7. I downloaded the app but it tells me my Samsung galaxy alpha doesn't have a barometer. I'm an engineer but I'm not going to build one for my phone. I'll keep weatheunderground for now but I'll make a donation to help the cause.

  8. Oh blast, not available in the UK!

  9. Amazing. Great app. I'm impressed by how many different functions you've included. Thanks.

  10. Whoaz that wind direction plot sure seems inside out (angular five days around creating a pentagon, radial representing direction from N at the center to NNNW at the end).

    This 30yr climatology graph of solar radiation is interesting. It's indicating July solar radiation of 240W/m^2. Is that our 30yr average maximum daily radiation for July? I would expect that to be considerably higher, so I suppose this graph is average daily average radiation (divided by 24hr/day instead of dividing by hours of sunlight per day).

  11. I'm still getting "server down" messages. Are you referring to stuff in google play unnecessarily? If you really mean to collect data annonously it should only send data to your uw services.

  12. I see that you want to spread this far and wide- unlike so many promising apps that are "IOS only," this one will reach the great majority of cell phones that are Android.
    Way to go! You'll get a lot more info this way, though IOS is pretty important to have, too.

  13. What makes this "the best altimeter around?"

    As a hiker, how does this compare to my Garmin and Suunto altimeter watchers?

  14. wait wait wait, stop the presses- "You're phone does not have a barometer" ?!?

  15. Works great on my Samsung Note 4. I have two favorite cities and wish the app would pull up radar in the second one... but nope, only for my "most favorite" city. Or maybe I'm doing it wrong?

    Anyway, excellent.

    A little hard to find with such a short name.... you have to get the three letters exactly right or there are a heck of a lot of UW(something) apps to wade through.

  16. I can't find it in the apple store for iPhones...is that app in the works?

  17. I assume that you'd make the source code available if there were an iOS developer who would be interested in making an iPhone port. There are iPhone barometer / altimeter aps (see https://itunes.apple.com/us/app/barometer-altimeter-for-iphone/id923043780?mt=8 for an example), so the necessary hardware seems to be there. This sounds like a great opportunity for a CS student, or someone trying to get started as a app developer. Just out of curiosity, how many lines of source code are there?

  18. Unfortunately, I had to remove the app from my Nexus 5, the app would cause the GPS to become unstable/unusable such that I had to restart the N5 to be able to use Google Maps.

  19. I quickly installed it when Cliff first mentioned it. 2 weeks later I kicked it to the curb. It sucked battery juice like crazy. I'd drop from full charge to 20% in about 7 hours ( overnight, while I slept). Great idea, too power hungry.

  20. Well after a couple of days of "server down for maintenance" I assume that this app makes some calls to the Google Play store and that fails, then the app posts this message. So I'm deleting it. Looks like you need better fault tolerant design of the software. If you care to open source it on github, post a link and maybe someone will help your students out.

  21. I am excited about barometer feedback from individual phones! Crowd sourced weather! Similar to the way Waze revolutionized traffic conditions from feedback from individual real time users (now embedded in Googlemaps traffic....) or how our jets at Alaska airlines stream near real time weather observations to NOAA as they move thru the atmosphere, like weather balloons, everywhere we fly, in the entire column of air.

    A perfect way for Google to continue to contribute to society where crowdsourcing is done for the good.

    I am looking forward to when you can get iOS version of the app, Apple also can get in on the good thing that is this.

  22. So far, so good.

    I'd like a clearer view of the altimeter without having to use the hiking function. Maybe show a feet reading as well as mmHg on the Smartphone Altimeter chart?

    I've also never had the elevations load from GPS or the USGS elevation in the Hiking function.

  23. I missed this the first time around. Really need to do an iPhone version if you want more coverage. Looking at handsets on our network two days ago, 51% are iOS and about 30% ar Android with the remaining being Windows and other operating systems. It would be good to port it over to make it available to the largest base of users.

  24. This is a brilliant concept. Have you approached Weather Underground? This seems to exactly fit their model.

  25. A good reason to trade up my old Moto G which has no baro. But that spinning wind pentagon is driving me crazy!


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