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I am extracting data from WRF model output for a specific area. The area I am extracting data for is 5000m above mean sea level. When plotting on a graph, I found that the dew point temperature is higher than the dry bulb temperature.

Is it possible that the dew point can go higher than the dry bulb? If yes, what is the inference of this phenomenon? Or can I simply assume that WRF could not calculate temperature values properly for this hill station?

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Dew point gives an indication of the moisture content of air; it is the temperature at which air can no longer hold water vapour.

The following graph shows the relations of dew point to air temperature (dry bulb) for various levels of humidity.

enter image description here

For humidity less than 100 percent, the air temperature is always higher than the dew point temperature and for a humidity of 100 percent air temperature equals the dew point temperature.

The dew point cannot be higher than the dry bulb temperature, it can only be lower of equal to it.

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    $\begingroup$ I am aware that dew point is "the temperature at which air can no longer hold water vapour". I was in doubt when WRF output file produced such conflicting output dewpoint data. That is why wanted to confirm from others. Accepting the answer. $\endgroup$ – sundar_ima Apr 30 '16 at 17:05
  • $\begingroup$ I think there is debate here. What if the air is super saturated? Will dew point cross over the dry bulb temp? Here is the link articles.chicagotribune.com/2011-07-20/news/… $\endgroup$ – sundar_ima May 2 '16 at 16:16
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Yes/no. In a cloud microphysics standpoint, you do need relative humidities greater than 100%, otherwise you cannot form clouds. However, for WRF output, you may want to check the script you are using to compute the dewpoint temperature. You may also want to check to see if you have editted the microphysics code.

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  • $\begingroup$ I have checked my script and it seems to be OK. RH increases more than 100 only when I extract the data for a station which is 7km above mslp. For the rest of the station it is only maximum (100) when rainfall happen. $\endgroup$ – sundar_ima May 8 '16 at 4:19

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