Harmonization and Verification of Three National European Icing Forecast Models Using Pilot Reports

Table 1

Thresholds used for the transformation of the original icing index potential based on ARPEGE and UM to the four-step range used in HarmonICE.

HarmonICE	ARPEGE	UM
No = 0	0	0–0.59
Light = 1	0.1–3.9	0.6–0.79
Moderate = 2	4.0–7.9	0.8–0.89
Severe = 3	8.0–10.0	0.9–1.0