The National Weather Service is currently predicting a 100% chance of rain for Southern California…for Friday, February 28. And they say it could be a decent-sized storm.
Obviously, no one storm is likely to yield enough moisture to make much of a dent in our drought but it's very unusual for the N.W.S. to make a 100% prediction more than a day or two in advance, no matter how the weather systems are lining up. This is eight days from now.
In the meantime, AccuWeather — the largest private weather service — is hedging their bets with a 99% prediction for that day and they're talking about an inch and a half of precipitation. The N.W.S. never does quantities this far ahead. Then again, I wonder how often either predicts the chance-o'-rain with such certainty that far in advance.