A forecast is an opinion produced by combining measurements and calculating from them, not a claim to see the future. However much data narrows the odds, the future itself still cannot be seen, so a forecast can be honest and still wrong.
While plants and animals had been sorted into categories, the sky stayed unclassified, so its changes looked like random chaos. Building a shared vocabulary of cloud types and graded scales of wind force turned the sky into something that could be recorded, compared and finally predicted.
Claims to predict what everyone thinks is unpredictable get laughed at and fought by people whose interests are threatened. The pioneer is caught either way: offering forecasts without a theory draws attack, and committing to a theory draws attack too.
Storms can outrun the fastest horse, so knowing about a storm somewhere else is useless unless the news travels faster than the weather does. Prediction only became possible once observations could be gathered from far away and sent ahead of the storm itself.
When storms are read as signs of God's displeasure, there is no reason to measure them, and searching for ordinary causes looks almost impious. Science advanced once data and observation, not divine intention, became the test of an explanation.