Altitude not working for a given locatoin
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User story: When I am looking at a forecast for a given location, I want to be able to view & adjust the forecast altitude (the same way Mountain Forecast allows) so that I can be confident of different weather conditions at different altitudes
Feedback:
Love this app in so many ways, but this is a big blocker for me (and several of my friends): the altitude doesn't seem to be working (at least in the WebUI) so it's either a bug or a broken feature. Please check out Mountain Forecast for the exact feature I want!Repro steps:
In the 'compare forecasts' for a given location (the top of Mount Rainier) it shows what I think are lower elevation temperatures. The different models are all providing very different information, so I can't be sure which is best.
Compare this to the same date (Friday) using Mountain Forecast. I'd love to be able to select different altitudes
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@William-Alpine
I don't know how Mountain Forecast works. In Windy you can adjust the altitude but it provides the various parameters in “free atmosphere” and not near the ground. In the case of Mount Rainier this will give a forecast close to reality because the summit is isolated, but it will probably be wrong in the bottom of a valley. Setting the Altitude slider at Mount Rainier elevation gives a temperature of 31°F.
At high ground levels medium resolution models like ECMWF 9km or GFS 22km cannot provide a correct temperature because of their coarse topographic model and the spacing between their grid points. The altitude at which the model "sees" the summit of Mount Rainier is indicated at the right end of the forecast table.
For example with ECMWF
Reason why it forecasts right now 44°F
You see that the discrepancy is smaller for HRRR 3km than for ECMWF 9km.
HRRR is forecasting 32°F.
Then Windy also offers a model that provides the temperature at the actual altitude, this is the METEOBLUE model only available in the detailed forecast table.
It forecasts 30°F
In mountain, use the highest resolution model or use Meteoblue. But this model is not available as a map overlay, only in the forecast tables.
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@idefix37 thanks so much for promptly clarifying! Now I have a better understanding of how it works.
Based on what you just described, If I could parlay my confusion into one small feature request that I think would take less than an hour of dev time, and alleviate pain for lots of users.
Would you be so kind as to review the following and hopefully pass this along to the product team?
User story: As a user, when I am comparing different models for a given location, I want to be able to view the elevation for each model forecast, so that I can understand which models I should be using for decision-making.
Implementation Suggestion: In the 'compare models' view, add a string that prints out the elevation for each model forecast. I don't need the ability to choose different elevations the same way I can with Mountain-Forecast.com (allegedly, Mountain Forecast uses ECMWF and GFS and then adds some custom modeling, with hit-or-miss results).
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@William-Alpine
In the “Compare” table, your suggestion would be helpful: displaying the elevation of each model.
This could be in addition to another user request for this table: displaying the latest update for each model.
By the way You have posted 3 identical messages, likely because they were pending approval. There is a lot of spam we need to review first. I've deleted your unwanted posts and now given you direct access to the forum. -
I've had a similar issue to @William-Alpine. I usually look at ECMWF meteograms for specific locations, which display the elevation at the right. Here I've clicked on two nearby locations that differ by ~1500m of elevation. The meteogram shows almost identical temperature forecasts, because as the "model elevation" indicates, the model is (I imagine) being queried for the elevation that its much lower-resolution topographical model thinks the surface is at:
While I appreciate that, given enough knowledge, the user can figure out that despite the map taking up most of the page saying "2500m", and "Elevation" at the right saying "2500m", that the forecast is for the "model elevation" of 1500m, this seems to me a pretty high expectation for the user's knowledge. Further complicating matters, there is a slider for elevation/pressure that adjusts variables on the map, but doesn't change anything on the meteogram.
I don't know how feasible it is, but my understanding was that it's generally possible to query each model for the elevation that is shown on one's own (high-resolution) topographic model, such that every model is displaying the forecast for the same elevation. In my imagination this was how windguru, for instance, gives a comparison of different models at the same forecasted elevation, rather than different elevations for each different-resolution model.
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@psathyrella said in Altitude not working for a given locatoin:
I don't know how feasible it is, but my understanding was that it's generally possible to query each model for the elevation that is shown on one's own (high-resolution) topographic model, such that every model is displaying the forecast for the same elevation.
You cannot query each model at a precise ground elevation. The topography model(mostly call orography model) used by each model is very coarse.
Note this old model used in Switzerland is a high resolution model so it is worse with medium resolution models.
You can’t compare exactly models at the same ground elevation. Or it is in “free atmosphere” not at ground level.
However, at ground level, the temperature may be lower in the morning and higher in the afternoon than that displayed with the altitude cursor set at that altitude.
This is easy to verify with Airgram at a location at a true altitude close to 2,000m, corresponding to a pressure of 800 hPa. The temperature variation is roughly stable over the course of a day on Airgram, but it is much more pronounced in Meteogram at ground level, especially in cloudless weather.
