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Windy.com

1052 points| kaycebasques | 4 years ago |windy.com

212 comments

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[+] mmaunder|4 years ago|reply
Windy is great. The map is appealing, but be sure to check out the forecast view for a particular location. Also make sure you try different locations. I'm in the Salish Sea on Orcas Island in the San Juans and because we have a lot of topography here mixed with ocean, we have a lot of local effects, contour winds and so on and there are big differences between locations.

Also note that Windy can get it wrong. I grew up in Cape Town and forecasting there is easy compared to here because it's the tip of Africa surrounded by Atlantic and Indian Ocean. Here it's very mixed with land, sea, big 11,000ft mountain ranges like the Olympics and so on and this region is hard to forecast. For where we are, the forecasts - and Windy's map specifically - is wrong fairly often.

A trick that a lot of folks don't know about is using ATIS, AWOS or ASOS at a local airport or airfield. If you want to know what the weather is at a given location, find a nearby airport, get their ATIS (or AWOS or ASOS) phone number and you can call and get a real-time report that is extremely accurate. I do this for KORS, our local airfield all the time. You can get this data off Foreflight although I'm sure there are plenty of free alternatives. Obviously it's current weather, not forecast, but it's often helpful.

[+] EMM_386|4 years ago|reply
> , find a nearby airport, get their ATIS (or AWOS or ASOS) phone number and you can call and get a real-time report. Obviously it's current weather, not forecast, but it's often helpful.

The US Government makes both METARs (current report) and TAFs (area forecast) available online. You can also get PIREPs (pilot reports) if you are interested in the conditions in the air.

[+] sealaska|4 years ago|reply
When you say Windy can get it wrong, isn't it really the underlying forecast models that are wrong?

It's unclear to me if Windy is doing much more than creating a great presentation of existing data. Their website does list an open ML role, though..

I wonder how much rolling your own weather forecast is tantamount to rolling your own crypto??

[+] 1vuio0pswjnm7|4 years ago|reply
"If you want to know what the weather is at a given location, find a nearby airport, get their ATIS (or AWOS or ASOS) phone number and you can call and get a real-time report that is extremely accurate."

To get the phone number:

     curl -Ls https://www.airnav.com/airports/get?s="$1"|sed -n '/<TR>.*WX/{s/.*=right>//;s/&nbsp;.*top>//;s/<.*//p;}'"
 
For example, Orcas Island

     curl -Ls https://www.airnav.com/airports/get?s=orcas|sed -n '/<TR>.*WX/{s/.*=right>//;s/&nbsp;.*top>//;s/<.*//p;}' 
or, without the redirect

     curl -s https://www.airnav.com/airports/KORS|sed -n '/<TR.*WX/{s/.*=right>//;s/&nbsp;.*top>//;s/<.*//p;}'
[+] themodelplumber|4 years ago|reply
You live in a beautiful area. I grew up scouting around there...on one trip we were invited to embark & leave Eastsound earlier than anticipated because a couple of our members decided to "casually" lift some cigars from a store there (IIRC). xD Thanks for the ATIS info too. I wonder if it's the same type of message I hear on non-noaa VHF from nearby.
[+] davidjade|4 years ago|reply
Another thing to consider is the difference between a global scale forecast mode (GFS, ECMWF) and a mesoscale model (HRRR, NAM, RAP). The later uses a much smaller grid size and can take into account terrain. In a place the the San Juan's (and the PNW in general), a lot of the weather patterns are coastal terrain driven so these models can be much more accurate. They catch is, they don't see out of far due to their higher computational complexity.

Here is a great resource to read up on the various models (there are far more than Windy offers): https://luckgrib.com/models/

[+] lr|4 years ago|reply
1000% agree! I sail and Windy is great for an idea of what is going to happen, but no substitute for what is actually happening on the water, i.e., the fine-tuned weather that is necessary to sail a boat. If you want to know a hurricane is coming or the potential for a "weather event," then Windy is truly your friend. Otherwise, what the OP wrote is totally necessary. For sailing, you want to look at lighthouse weather data (e.g., NOAA) and the numerous buoy systems (e.g., https://buoybay.noaa.gov/) really are your friend.
[+] aidenn0|4 years ago|reply
I live less than 3 miles from an airport, but due to microclimates the weather is completely different. The NOAA does a reasonable job of forecasting my specific area, but most weather apps will take the current conditions from the airport, which can be off by over 10F in temperature alone.
[+] hutzlibu|4 years ago|reply
"Also note that Windy can get it wrong."

I kind of lost trust in it, when I was in the middle of a thunderstorm, yet windy showed me all sunny.

Granted, it was in the alps and forcasting there is hard, but it was the current state of things they got wrong.

[+] jschwartzi|4 years ago|reply
The forecasts for the US at forecast.weather.gov are really good too. I constantly refer to the hourly precipitation charts to figure out how much rain gear I should hike with, and their temperature predictions are useful too. Plus if they have any warnings or watches it’s helpful. It’s much better than any of the paid services out there.
[+] criticaltinker|4 years ago|reply
Also worth mentioning that Windy provides several different forecast models that you can choose between. There are high resolution models like NAM, and lower resolution models like GFS - toggling between them often gives me a better sense of what to expect.
[+] ISL|4 years ago|reply
If you're in the Pacific Northwest, specifically Washington/Western Washington, then UW's weather models reach much higher spatial resolution than Windy appears to do.

https://a.atmos.washington.edu/mm5rt/

I recommend starting with the 4km or 1.3km WRF-GFS model and looking at something like 3hr Precip.

[+] oxml|4 years ago|reply
I live a couple islands over from you. As a frequent sailor, I use Windy regularly before a race, but it's never completely accurate (PredictWind tends to be better). Great for looking at general trends and visualizing patterns. This area is tricky — lots of microclimates for the reasons you mentioned and it's almost impossible for a service like Windy to be completely accurate.
[+] bujak300|4 years ago|reply
The forecast that worked best for me (at least in summer in Europe) was local sailplane text forecast from the respective national service. It was an interpretation of the model by a very experienced human with a big picture introduction ("this front" or that "high pressure area") and also expressed uncertainties. They are sometimes behind soft paywalls, though (need to register, but its free. There are some weird rules of the EU about some weather data - cannot be freely available. I don't get it)
[+] rastafang|4 years ago|reply
> Windy is great.

I don't like the zooming ratio

[+] rrix2|4 years ago|reply
over the past few years my use of weather apps + forecasting has really been improved by reading alongside them the local NWS office's "area forecast discussion"which is published multiple times a day by the station's meteorologists: https://www.wrh.noaa.gov/total_forecast/getprod.php?new&wfo=...

It's really great to be able to contextualize the state of a Windy map, for example especially in Seattle where the weather patterns are tightly influenced by the Olympic mountains and other local conditions which these global maps usually fail to capture or express well.

Windy is impressive stuff but looking is half the battle with these maps, wind directions and "that weather blob is orange right now" only really go so far when your weather area's geography isn't simple; in fact, i think that the older static Weather Channel style maps which expressed the pressure gradients and fronts better and helped you build a model of what the weather is doing rather than which way the wind is blowing. (see https://s3.us-east-2.amazonaws.com/journeynorth.org/images/g... for an example)

[+] dang|4 years ago|reply
Some past threads:

Live View of Hurricane Laura - https://news.ycombinator.com/item?id=24289287 - Aug 2020 (54 comments)

About Windy (2018) - https://news.ycombinator.com/item?id=21701065 - Dec 2019 (34 comments)

Typhoon Lands in Japan – Windy Storm-Tracking Platform - https://news.ycombinator.com/item?id=21232332 - Oct 2019 (44 comments)

How wind and geography influences wildfire smoke - https://news.ycombinator.com/item?id=18416850 - Nov 2018 (6 comments)

Windy.com - https://news.ycombinator.com/item?id=15094639 - Aug 2017 (103 comments)

[+] tunap|4 years ago|reply
Even before 2017, I recall reading here about... windy.tv(?) or some sort of odd extension. Shortcut has been in my toolbar, url updated 1 or 2 x's, since. A great resource when travelling by road looking to avoid high winds, rain, sleet & snow.
[+] sealaska|4 years ago|reply
Windy is fantastic.

But, I'm curious if there are any apps or weather models that give probability distributions? Telling me that it is going to blow 10 mph is useful, but telling me, for example, that there is a 60% chance that there will be a 10 mph wind and a 40% chance that the wind will blow at 15 mph seems more in line with how I would naively assume weather forecasting works.

Right now, the ECMWF [0] model in Windy shows 6 mph winds gusting to 30 mph for my area (SE Alaska, with lots of mountains and fiords, so a area that is gusty and hard to predict by nature). It almost feels like they're throwing their hands up in the air and admitting that they have no idea what the wind will actually do today. Which, is fine, if that's the case.

I just wish consumer weather forecasts did a better job communicating probabilities and uncertainties instead of spitting out a single value.

[0] https://www.ecmwf.int/

[+] shoyer|4 years ago|reply
ECMWF makes probabilistic forecasts, in the form of an ensemble of 50 IID examples. So this is mostly matter of Windy figuring out how to put that information into their UI.
[+] aeharding|4 years ago|reply
Windy does allow switching between different models, which can be helpful to roughly gauge probability. Definitely not perfect though. And some of the models are consistently inaccurate for specific locations in certain conditions in my experience.
[+] nharada|4 years ago|reply
If you click on a specific location, at the bottom you can expand the forecast. Instead of "Basic" select "Wind" which will let you see multiple model forecasts. Not exactly a probability but you can do some mental ensembling to see if models agree or not.

https://imgur.com/a/UezBGqZ

[+] ortusdux|4 years ago|reply
They have been my preferred weather source for a few years now. Forecasting is spotty in my area, but they have a feature where you can quickly compare 4 weather models, which tends to give a good overview. They also have my favorite android widget.
[+] sva_|4 years ago|reply
> but they have a feature where you can quickly compare 4 weather models

meteoblue.com offers 18 models if you click on 'MultiModel'. I found them to be very reliable.

windy.com is cool though, respect to the Czech founder https://en.wikipedia.org/wiki/Ivo_Luka%C4%8Dovi%C4%8D

[+] evilpie|4 years ago|reply
I have been using the similar site https://www.ventusky.com for a few years now.
[+] smalley|4 years ago|reply
There's also https://www.predictwind.com/ which is a (very expensive) commercial service a lot of boat/yacht folks use for planning. I believe they also have some utilities for delivering compressed forecast data over satellite link as well.
[+] yardshop|4 years ago|reply
Windy looks great, I will add it to my daily weather websites.

My primary visual weather site is the National Weather Service Enhanced Data Display.

https://preview.weather.gov/edd

It's been "*Experimental*" for several years, and the site looks kind of dated, but it provides a useful visualization of radar, satellite, tropical storms, etc, plus it runs on my old PC! =)

I also like the NWS Hourly Graph to give a better idea of for example when it's going to start or stop raining or go below freezing on a given day.

This is the forecast page for my area:

https://forecast.weather.gov/MapClick.php?lat=43.7445&lon=-7...

Put in your own zip code, or type in town and state (sorry, just US). Then click "Hourly Weather Forecast" below the daily descriptions to get this:

https://forecast.weather.gov/MapClick.php?lat=43.7445&lon=-7...

There's no location picker on that page though.

[+] Syzygies|4 years ago|reply
Other than the canonical "Do I bring an umbrella?" we have one actionable need for precise weather forecasting:

In hot weather I have outfit our California house with an assortment of commercial (quiet whole-house exhaust) and homebuilt (computer fan arrays in each window) fans. We rarely use air conditioning even in extreme heat, instead waiting till outdoor air is cooler than inside air to open up the house overnight. It's important to hang box fans between rooms to stir the air as much as possible; one is storing coolth in the walls. People are always surprised we're not on AC when they come inside the next afternoon.

As we're both on east coast schedules I sometimes have to set an alarm to get up and open up the house. This is guesswork. Better forecasting would really help. I don't see any multimodel tools in any of these paid apps that give me a better view, zooming in on this precise question, than a generic hourly forecast by the usual suspects.

(New construction near us forces a reliance on AC. One would think that in regions with good daily temperature swings, designing a house like a water-cooled computer would make sense. We should be seeing as many rooftop radiators as solar panels. Not a thing...)

[+] aasasd|4 years ago|reply
I occasionally meditated for a bit upon a similar map on Yandex Weather—finally understood what the deal with Siberia is. Like, in spring it's way below zero around Mongolia, while it's on the same latitude as Black Sea where it can already be +20°C. Well, turns out I can clearly see warm air moving from the Atlantic eastwards—until it hits the Urals and stops, and everything beyond that is frozen tundra. Warm air from the Pacific somehow barely reaches Siberia, deciding to turn east or west instead.

Really nice to just watch this on the screen in realtime.

Also in the rain map, it's fun to look at huge clouds spanning entire Europe. Especially if my city is precisely in a small window of clear skies amid the rains.

[+] aeharding|4 years ago|reply
windy.com is great for forecasts, but you have to be careful of the model used for certain sports. (For example, the NAM model can be more accurate for low wind gusts.)

In my spare time over the last couple weeks I've been building a PWA for paramotor pilots to better visualize winds aloft: https://ppg.report.

Wind modeling - especially for aviation - is really an interesting subject. The main API I use at ppg.report is https://rucsoundings.noaa.gov/, lots fun to learn about (CIN, CAPE, the historical "soundings" manually reported from aircraft and balloons, versus the modern ones automatically pulling data from commercial flights.)

[+] mhandley|4 years ago|reply
I also really like https://earth.nullschool.net/#current/ It's not so useful as a forecast, but you can move around the world and see everything so well. Take a look at the winds in the Southern Ocean for example, and you can see why it's so tough to sail there.
[+] dr_dshiv|4 years ago|reply
In the future, I really look forward to owning a globe that shows time-lapse clouds in very high resolution.
[+] themodelplumber|4 years ago|reply
They are running an impressive show all around, check out their webcam embeds and API, great for spotting fires and things, plus they have their own online community forum. Their mobile app is really good too, includes offline map capabilities, and I take it on hikes for tracking.
[+] bscphil|4 years ago|reply
The wind animation doesn't work at all for me in Firefox (on Linux, version 91). I see a few large animation "sheets" where the wind is moving in the same direction, depending on where on the map I look. Works in Chromium. Anyone else have this problem?

Screenshot: https://i.imgur.com/eLyQa6X.jpg

[+] H8crilA|4 years ago|reply
Reminder that weather forecast apps/websites/anything are pretty much all just different UIs for the same underlying global forecasting models. With the NOAA's GFS being the most widely known one. You can find historic forecasts on NOAA's website going decades back.
[+] hugoromano|4 years ago|reply
I was paying for it, but didn't renew the subscription, this year in 90 days that I needed forecast was way off in 42 of them, and trying all their different model offers. Maybe next year I will resubscribe, depending how their models forecast over Fall and Winter.