Isotachs 300 hPa:
Jet stream relevant for the development of the Jet Fibres flows along the rear side of the front. Fibres are found within the jet streak, which corresponds to the ideal distribution.
Shear Vorticity 300 hPa:
Zeroline of shear vorticity represents the jet axis. Fibres are in this case found along the zero-line of shear vorticity just very slightly shifted to the anticyclonic side of the jet.
Vertical Motion (Omega):
The values of omega are not correlated with the Jet Fibres. Ascending motion can be seen within the frontal zone and it is the mechanism of the development of frontal cloudiness.
Relative Humidity 300 hPa:
Upper-level relative humidity maximum corresponds nicely to the frontal cloud band, but there is no maximum in the region of the Jet Fibre. This has to be expected because of the coarse resolution of the ECMWF model.
Relative Streams:
There is a relative stream rising from the front to the rear side of the frontal cloud band. The limiting streamline should be at the jet axes, but in this case this is not very well seen.