Efficient techniques for updating the IRI model in disturbed conditions at subauroral and mid-latitudes are described. The quantitative characteristics of the ionospheric effects caused by magnetospheric substorms and sudden commencements of severe magnetic storms in the dark ionosphere are depend on the AE-index, solar activity, season, local time and geomagnetic latitude. During magnetic storms updating is performed with the aid of analytical expressions describing the foF2 and hmF2 variations caused by global thermospheric modifications. The temperature, composition and density of the neutral atmosphere are taken from the MSIS-86 model for different levels of the magnetic activity. Since the AE-index could not be obtained in time from WDC a method to estimate of the AE-indices during severe substorms is suggested. Compliance with the concrete situation is reached by the use of a weighted summation of deviations of foF2 and hmF2 model minus observed foF2 and hmF2 values. Ionospheric modelling in disturbed conditions is considerably improved by these techniques.