Another interesting case happened on august 23th, 2014, nearby Cogoleto, again in the Genoa gulf area.



According to the Keul et al (2009) methodology:

- the synoptic type patterns associated with this waterspout episode was south-west flow (SW)



cloud elevation EL can be estimated from the cloud top temperature and height (CTTH), developed within the SAF NWC context, aiming to support nowcasting applications. This product contributes to the analysis and early warning of thunderstorm development.



CTTH from EUMETRAIN on 19 august 2014, 06 UTC (Europe region). On the Gulf of Genoa area EL is about 8000-9000 m.

- The lifted condensation level (LCL) can be estimated from Lawrence (2005)

Lawrence, M. G. (2005). The relationship between relative humidity and the dewpoint temperature in moist air: A simple conversion and applications. Bulletin of the American Meteorological Society, 86(2), 225-233.

as LCL=25(100-RH), where RH is the relative umidity at 2 m, predicted by COSMO-2.8 and MOLOCH-1.5 (23 august 2014, 00UTC run): LCL=25(100-90)=250 m.

Thus AZ=EL– LCL=9000-250=8750 m

- The sea surface temperature, as provided by the buoy located at Capo Mele servizi-meteoliguria.arpal.gov.it/boacapomele.html, can be estimated around 25.5 C on 23 august

The 850 mb temperature can be estimated around 12.5 C, as predicted by COSMO-2.8 and MOLOCH-1.5 (23 august 2014, 00UTC run): then, ΔT=Water–850 mb temperature difference=25.5-12.5=13 C

- The condition on W850 ≤ 40 kts (about 20 m/s) is respected as well: the wind at 850 mbar was about 10 m/s

-All together the result provided by the Szilagyi Waterspout Index (SWI) is



The larger the value of SWI, the higher the probability of waterspouts developing: in this case the probability was predicted very MEDIUM being SWI around 5-6, and indeed the waterspout developed.