Titles when screen recording
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@vsinceac Yes, but is MSLP at the surface. Models like WRF or GFS data provide information of pressure at different altitude levels. If not possible, maybe geopotential height at different levels.
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No, MSLP is not "Surface" ("Surface" may be well at 8000 m altitude in Tibet). As already said, Atmospheric Pressure is computed at a given altitude (or well measured by a barometer), then reduced to the "Mean Sea Level" for that position (with some formula which also implies temperature and latitude). No, GFS doesn't provide pressure at altitudes (with several exceptions, as said above), and btw. altitudes are measured by barometers, too...
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@vsinceac Yes, it is measured at the surface and computed at mean sea level. Then, the original data is take at surface from station measurements
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@vsinceac Yes, GFS netcdf files have information about preassure at different levels, take a look at https://www.ftp.ncep.noaa.gov/data/nccf/com/gfs/prod/ and read the netcdf
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Generally, WMO stations priovide both p (MSLP) and p0 (barometric pressure); p0 is not yet "Surface", it is measuread at barometer heigth above surface (may be several meters...)
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Nope, GFS doesn't... See the ful index of grids (parameter/level) provided by GFS model here (runtime today 00hUTC, validity RUNTIME+11h)
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@vsinceac you can plot pressure at different levels using GRIB2 files from GFS data. See some examples here: https://www.ncl.ucar.edu/Applications/height_lat.shtml
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using WRF forecast I think you can obtain pressure at diferent levels. For instance, in GFS data from your provided link you have this field:
98:60458921:d=2021110200:HGT:325 mb:11 hour fcst:
I'm sure is not so difficult to obtain pressure at specific level
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NB: HGT is not "Atmospheric Pressure", it is "Geopotential Height [gpm]". Otherwise: of course one can compute yet other hundreds of parameters based on the hundreds of parameters already provided by models... About pressure/altitude: one would need also Area QNH (pilots use measure of barometer on bord and Area QNH - computed by forecasters - related to a FIR in order to compute altitude...)
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I know, but you can interpolate one from the other. Again, see the example:
https://www.ncl.ucar.edu/Applications/height_lat.shtml -
Here a function in wrf that provides the conversion:
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As said above, you can interpolate everything from models... But better would be to don't do it and let the model provider or expert forecasters to do it correctly... Otherwise you become responsible about any fault in the computation (and then you'ld need a good lawyer :o)---
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@vsinceac Yes, but also there are still many fields computed from others...as for instance CAPE and many other parameters.
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Nope, CAPE is one of the provided grids in GFS model...
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@vsinceac But is a computed field, not measured
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... of course computed, like any othe grid (temperature, etc.) in the model .... But by people who know what they did.
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Not the wind, Temperature and others that are interpolated but taken from the weather stations data and other sources, but they came from reads of the sensors.
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Not for forecasts... A model computes values for the future, not for real-time data (for which the best is to use satellite or radar images, not models).
Look, I'll stop here at let Windy to answer... -
@vsinceac Of course, forecast is always computing, so why not include pressure or geopotential height at different levels?
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You should ask NCEP/NOAA about this...