
Show HN: Making pro weather data free for Hurricane Dorian - duanem
I have added OpenZones to Flowx, my Android weather app[0]. OpenZones are regions covering disaster zones where all the pro data in the app is freely available.<p>I have created an 1200km diameter OpenZone over Florida with Hurricane Dorian approaching. So if you add Florida to the app, you can view radar, NOAA&#x27;s GFS, NAM and HRRR models, CMC GDPS and RDPS models, and the DWD (Germany) ICON model. There are also predicted hurricane tracks from the NOAA and CMC ensemble models which I find extremely valuable to predict the possible paths of Dorian. This YouTube video[1] shows an example of the hurricane tracks.<p>The reasoning behind OpenZones is that meteorological organizations solve weather simulations and release data to the public with the aim to reduce damage, injury and fatalities. It&#x27;s only right to support this purpose and open up all data in disaster zones.<p>The idea for OpenZones came from the fires (Camp Fire) in California last year. I was part way through adding HRRR smoke simulation data to Flowx when a user asked if I could release the smoke data early for the California fires. I did so in the free version of the app and then rolled it into the pro version after the fires.<p>Sorry there is no Apple version of the app.<p>[0] https:&#x2F;&#x2F;play.google.com&#x2F;store&#x2F;apps&#x2F;details?id=com.enzuredigital.weatherbomb<p>[1] https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=h5do7dYfYfQ
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duanem
I believe the hurricane tracks is a solution to the problem outlined in the HN
post 3 days ago on "Misinterpreting hurricane forecasts"[0].

The hurricane tracks are a new addition to Flowx but I believe it can be
improved a lot. For example, you can color the dots by the hurricane category
or wind speed. Better still, draw a heat map around each dot would generate a
probability map for the hurricane.

[0]
[https://news.ycombinator.com/item?id=20833030](https://news.ycombinator.com/item?id=20833030)

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astrophysician
Not a bad idea but only if the tracks are independent. Was reading something
saying that these tracks aren’t different random realizations of the same
simulation (in which case what you’re saying is a good way to estimate the
posterior of the hurricane track — it’s just Monte Carlo) but that these
tracks come from many different types of simulations, some with higher quality
than others and they’re likely all correlated in some weird way. If it’s the
latter case there has to be some care and thought put into combining the
predictions into a single estimate of the posterior.

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duanem
The initial conditions of the weather simulation, which is based on measured
data and previous simulation results, are perturbed to within a reasonable
range to represent the error in the measurements. Because of the equations
being solved and numerical methods being used, these small changes can cause
large change on long term predictions.

The tracks come from one original simulation. If you look at the start of the
tracks closely, you'll see the eye of the hurricanes diverge in a regular
grid, so I'm guessing they are perturbing the direction and speed of the bulk
movement of mass - I would have to research more.

So the initial conditions and early stages of the simulations are correlated,
but each simulation is solved independently. The question is how long into the
future can you consider each track less-correlated.

Given the met organizations release probability envelopes based on these track
means it's a reasonable approach.

What I really want to do is weight the predicted wind speed with the
probability map. I don't know if this will work. But you can imagine if a
hurricane has a 75% change of going well into the continent it would weaken
and cause less damage, but if the other 25% of the tracks go over sea and hit
an island, it'll likely strengthen and cause more damage.

In any case, all the above will be interesting.

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cryptoz
This is cool! I will download.

I also have a Dorian-related Android app to share. I use the barometers in
phones to measure surface pressure with All Clear:

[https://play.google.com/store/apps/details?id=com.allclearwe...](https://play.google.com/store/apps/details?id=com.allclearweather.android)

Here is a graph of Hurricane Florence last year:
[https://www.allclearweather.com/hurricane-
florence](https://www.allclearweather.com/hurricane-florence). I will do a
much more geographical and full analysis for Dorian. The raw data from
barometers in phones is messy, and requires significant bias correction and
quality control, but one day could be assimilated into weather models like WRF
and improving forecast accuracy.

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usrlocaletc
For particulates in particular (no pun intended), purple is a good resource.
[https://www.purpleair.com](https://www.purpleair.com)

PS: In Paradise right now, incidentally.

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vcxy
I've been using your app for awhile now! It's quite good. OpenZones is a
fantastic idea.

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craftyguy
How does this post not qualify as 'spam'?

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lsiebert
It's informational, for the free version of the app, and you have to click on
it to read it. Spam is a term for unsolicited commercial messages sent
indiscriminately. Still marketing arguably, but then so is a lot of things
that get posted to HN.

~~~
duanem
Thanks. I was going through my memory of previous "Show HN" posts I've read
and many are products.

If it's any consolation, we don't have a marketing department or budget :-)

