Thank you all for reporting this, it should be fixed now.

@gkikas-lgpz thanks for info. I will have to check it in more detail, just few quick remarks:

• Germany - we know about it, their alert feed doesn't correspond to what is a "standard" for other EU countries. separate parser will be developed for that
• general disrepancies between Windy/meteoalarm - it already happened many times, that meteoalarm shows different alerts from the ones reported in the data feed. we found a cases where alert was not visually shown in the metoalarm map, although it was present in data feed and was valid and active in given time period. Same happened vice versa - alert shown in map was not present in data feed.
• also the understanding of how to treat today/tomorrow differs between Windy and meteoalarm

We plant to fix/change couple of things in CAP alerts layer, once this is done, I will provide more detailed post of how it is implemented and how to treat the data provided by that layer.

In the meantime, if you really want to compare Windy against the source, you have to check the data source itself, not the resulting map at meteoalarm (example for Sweden can be found at http://meteoalarm.eu/ATOM/SE.xml). If you find a discrepancy there, please let us know

We, surfers, waveriders, divers and sailors need an accurate tide forecast. Tides can only be forecasted at "tide stations" that measure actual sea levels in time. We estimate, that there is 15 - 30.000 tide stations in the world, yet we at Windy, were able to gather data just from 10.000 of them.

Let's create a creative commons database, where the community could submit tide stations in the world, and upload the (time to time) latest measured data. The open source web application for gathering these data would calculate harmonic files, and these files would be available for free for anyone in the world.

Not only would we be able to surf, sail or dive better, but we would increase overall marine safety.

We believe that this information should be free.

Ivo, the founder of Windy

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Technical part from @kekert who programmed tide backend on Windy:

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What is needed?

In order to be able to accurately predict tides for given location, set of harmonic constituents derived from water data levels are necessary. Either harmonic constituents itself (usually hard to get) or water level observations (can be taken from local boating magazine, chartbook, yacht club or marine authority) are sufficient. We believe that there is a widespread demand for free, creative commons database of harmonic constituents which can be used to predict tides. We believe that this creative commons database, can help other people dependent on tide levels to avoid all dangers and enjoy all possible fun using these shared information.

In our eyes, any information that can provide more safety to people should be always free to use. Ever.

How to achieve it?

If you are a programmer, wanting to help other tide freaks, we would be happy if you decide to develop open source web application for adding, editing, parsing and transforming tidal data. Let’s call this process tidal data munching.

• You will develop web application for munching tide data using the technology you like. The codes of app should be, in our opinion, open source and hosted on gitHub.
• Application users should be able to add/edit either harmonic constituents itself, or water level observation (at least a year's worth of hourly water level measurements is recommended). As output, database of harmonic constituents for tide locations should be provided.
• The condition is, that resulting harmonic constituents database is creative commons and it is easy for any other party to download and use the database.
• Windy will provide free hosting for this apps with nice domain name tides.windy.com
• As start, free to use data of harmonic constituents from The Center for Operational Oceanographic Products and Services (CO-OPS) can be used - https://tidesandcurrents.noaa.gov/stations.html?type=Harmonic+Constituents
• Windy will place a links from www.windy.com to tides.windy.com so we can guarantee that this site will have its users and spots contributors.
• Windy will enable you to use registering and authentication of windy.com so you do not need to develop it yourself.
• Windy will send you Windy cap and Windy towel (so far only swag we have now).

Data structure and recommended setup

The database should contain the following information:

• Location name + basic description
• Coordinates (latitude, longitude)
• Harmonic constituents for given location

We recommend to use the components described at http://www.flaterco.com/xtide/harmonics.html:

• Resulting data should follow the structure of Harmbase 2 (or at least the output format should be easily convertible to the one required by Harmbase 2) http://www.flaterco.com/xtide/files.html#harmbase
• Harmgen package should be used to derive harmonic constituents from water level observations http://www.flaterco.com/xtide/files.html#harmgen
  the reason for that is that a lot of complicated work have been done on these packages and we don’t see any other viable way of generation tide predictions at the moment.

More detailed description of recommended process:

1. collect user data:
   • either in the form of harmonic constituents
   • or as water level observations
2. clean data, prioritize, remove duplicities
3. transform data to output format:
   • for harmonic constituents, trnasform them to desired output format
   • for water level observations:
     1. transform data to the format understandable by http://www.flaterco.com/xtide/files.html#harmgen
     2. Harmgen produces results in the form of an SQL insert statement that loads the new station into Harmbase 2

Example of harmonic constituents data for single location from CO-OPS:
https://tidesandcurrents.noaa.gov/harcon.html?unit=0&timezone=0&id=9411340&name=Santa+Barbara&state=CA


A small warning at the end

A lot of low level programming and tweaking (especially in C) will be needed to perform this task.

Quote taken from Xtide webpage:
“All pretense of user-friendliness stops here.  If you want to do large numbers of stations without lots of manual data entry, you have two options, both of which require a high level of computer literacy.”

Taken from HarmBase readme:
“Harmbase is a database application for managing harmonic constants. I built Harmbase to solve my own problems, so it's not "plug and play" software. It's not designed to be useful to someone who does not know how to hack C code or write interactive SQL queries. Given the nature of the problem--turning unstructured data from random sources into structured data--I doubt that anything but hackware would be feasible.”

How to proceed

Just let us know that you are interested and we can go!

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Wave tide forecast on Windy? Where will I find it?

We are testing new tide forecast right now. Jest check the details here: https://community.windy.com/topic/4841/help-us-to-test-new-tide-forecast-experimental-feature

@krchnavy there is such detail, just use the zoom in lower right corner

@tomber42
German feed had different structure, now it was added too.

Thanks for the info, this is obviously a bug. Will be fixed soon.

@gkikas-lgpz German was added + some bugs in alert processing and time filtering were fixed. Please note that we are not displaying any warnings with Severity below Moderate.

it should be fixed by now

@maila7 it is done now, data are being sourced directly from CHMI. however, if same alert applies for whole region, it is being grouped and shown as whole...

hello @stevecrye, could you please specify which spot are you talking about?

Dear @williamspeaks, thanks for your effort. Could you please provide us with ids of the webcams you mentioned? Or at least name or approximate location. I'll be able to tell more once I check them...

Checking webcams linked to your account, there is just one and that is still active: https://www.windy.com/-Webcams/United-States/Larimer-County/webcams/1589658275?40.447,-118.916,5

@Sam-Phisher thanks for notice, this is obviously a mistake, we will take it down

hi @EricJ , still there, it just moved:

@mhaberler yes, we are processing more now (as we added more sources, fixed some bugs & upgraded packages)

@mhaberler @wetterheidi thank you for your input!
The stations you have mentioned are back, see https://www.windy.com/station/wmo-10982?47.883,12.533,8 https://www.windy.com/station/wmo-10962?47.798,11.019,8 and https://www.windy.com/station/wmo-10961?47.417,10.981,8

We will continue to process your list of stations in order to have as much as possible WMO stations at Windy.

Dear @czollars, we have this feature implemented for the global providers (CamStreamer) and will inspect the possibility of exposing it to general public. Will keep you updated about the progress.

hi @idefix37 can you please try without logging in, in an anonymous tab?

Dear @farview, thank you for reporting this. In such case we have to manually merge the old webcam with the new one. We also have a solution for duplicate detection, we just need to turn it on for camstreamer upload too. We are glad you like the integration.

hello @seejacksonhole. we don't ever change ID of the webcam, that has to be some confusion on your side. the webcam can however be disabled (happens from time to time), or be merged with some other webcam (in such case, old merged webcam is redirected to the new one). In any case, unless the webcam is disabled, original link will always work (unless you are doing some undocumented/unsupported hacking...)

@idefix37 thanks for reporting this, it is fixed now.