Vaisala IRIS - Table 13 Warning Criteria Examples

The following table shows some examples of warning criteria. Each criterion, surrounded by
square brackets above, is one task. The results of multiple tasks are ANDed together.
Table 13 Warning Criteria Examples
Criteria Example
Wind shear detection
[Shear >10 m/s/km at 0.5° EL]
AND
[ ... at 0.7° EL]
over an area of 3 km
2
(1.2 mi
2
)
Storm turbulence detection
[Spectrum Width >6 m/s (>19 ft 8 in / s)]
AND
[Reflectivity >20 dBZ]
over an area of 10 km
2
(3.9 mi
2
)
Hail detection
[45 dBZ TOPS >1.5 km (>0.9 mi) above freezing level]
over an area of 10 km
2
(3.9 mi
2
)
Precipitation surveillance
detection
[1.5 to 14 km (0.9 to 8.7 mi) VIL >1 mm (>0
3
⁄
64
in)]
over an area of 10 km
2
(3.9 mi
2
)
Severe storm detection or
lightning hazard
[1.5 to 15 km (0.9 to 9.3 mi) VIL >10 mm (>0
25
⁄
64
in)]
AND
[10 dBZ TOPS >8 km (>5.0 mi)]
over an area of 10 km
2
(3.9 mi
2
)
Flash flood warning
[Hourly Rainfall or N-Hour Rainfall >5 mm (>0
13
⁄
64
in)]
over an area of 25 km
2
(9.7 mi
2
)
Chapter 3 – Configuring IRIS Products
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