Wondering where the extreme winds are? Here's how wind predictions and warnings are made

Weather forecasters warned of extreme and "particularly dangerous" fire-fueling winds on Tuesday and Wednesday.

The great news: The gusts seemingly have not materialized in ways that would impede efforts to fight L.A.'s two major fires burning in the Santa Monica Mountains and Altadena areas.

The head-scratcher: It's not that windy in a lot of places in L.A. today. But that doesn't mean it isn't windy somewhere.

"We are seeing gusts of 45 mph to locally over 60 mph, even as we speak right now," said Ariel Cohen, head meteorologist at the National Weather Service office in Los Angeles. "Maximum wind gusts over the last several hours have actually gone upwards of near 70 mph around the Santa Susana area."

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"So even if it's not windy exactly where you are, you don't have to go very far to find those stronger winds across the area," he added.

Wind predictions are just that — predictions

As our climate becomes drier and hotter for longer periods of time, Southern Californians are also becoming more used to fire weather warnings from the National Weather Service.

They include red flag warnings and the recent warnings about a "particularly dangerous situation," or PDS, the highest echelon of red flag warning. Those are issued only when the agency is confident of its prediction and needs people to prepare.

 "When we're dealing with any weather outcome, there's always uncertainty," Cohen said.

When alerts are sent

The agency is monitoring weather patterns all the time. A PDS alert is sent when the winds are, according to Cohen, "damaging or destructive or capable of extreme fire behavior."

How the weather service makes forecasts

The weather service uses observations from wind sensors throughout the region to get information like wind speeds and directions.

Then they combine those with information about atmospheric pressures from satellite data, to gain "an understanding of how the pressures vary from place to place across the United States, to come up with an idea of what the winds are going to do over time."

It's the tried and true process to arrive at an educated guess.

"We use weather models to give us estimate, but no model is perfect," Cohen said. " And if something bad doesn't happen, then that's a very fortunate situation to be in."

The extreme wind forecast is slated to expire today at 3 p.m.