For a few days now many of the global models have been showing tropical storm Dalila moving southwest (even though forecasts have showing it move to the west). Why? A large tropical disturbance is developing in the far eastern Pacific. The environmental flow around this new system (which should be an Invest on Tuesday), combined with a robust ridge of high pressure to the north of Dalila – will combine to create an unusual steering pattern – forcing the relatively small Dalila to the southwest. Here’s a graphic showing the current computer model forecasts for Dalila, as well as the disturbance developing to the southeast:
If most of the global models are correct, Dalila will begin to move southwestward on Tuesday as the new, and much larger system to the southeast starts to develop.