[Paraview] Wind Velocity does not match cloud movement

[Henry Lau]

Hi,

I was visualising my wind velocity using glyphs and cloud water content at the same time. However, I notice that the direction where the clouds move do not match the direction the glyphs pointing. 

Below are the steps how I create the output:
The data is a netcdf file with wind variable array "ua" (eastward_wind_speed), "va" (northward_wind_speed), and "wa" (wind_vertical_velocity). 
I used a cell_data_to_point_data filter to convert them into point data.
Then I combined these 3 arrays using a Paraview calculator with the equation iHat*ua + jHat*va + kHat*wa.
Then do a glyph filter to visualise the wind velocity.

Attached image is the output I got.
The blue isosurfaces are the cloud water content while the glyphs are the wind velocity. The problem is, the clouds are moving to the left, which does not match where the glyphs are pointing at.

What would be the possible reason for this error? 

TIA
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