Speaking of predictions: Earlier today, the Southern California forecast from the National Weather Service said showers were possible for Wednesday-Thursday. Now, it says Wednesday will be partly cloudy and we have "A chance of showers" Thursday through Friday. How solid is this projection? About as solid as smog. The following is currently posted on the website where the weather forecasters discuss why they're predicting what they're predicting. (By the way, "CWA" stands for "County Weather Area" and all the other unfamiliar terms refer to different computer model projections based on satellite readings.)
BEYOND TUESDAY THE FORECAST REALLY GETS TRICKY. AS HAS BEEN THE CASE THE LAST FEW DAYS, THE MEDIUM RANGE MODELS HAVE BEEN ALL OVER THE PLACE, THOUGH THE TREND HAS BEEN TO TAKE THE LOW FURTHER AND FURTHER WEST (A VERY COMMON PATTERN WITH THE MODELS IN A SCENARIO LIKE THIS).
THE 12Z CANADIAN AND UKMET BOTH KEEP THE UPR LOW WAY TOO FAR OFFSHORE TO BRING ANY PRECIP TO OUR AREA, AT LEAST THROUGH WEDNESDAY. THEN MOST OF THE MODELS SEEM TO DROP THE LOW QUITE A WAYS SOUTH BEFORE SWINGING IT INLAND FRIDAY SOMEWHERE BETWEEN SAN DIEGO AND ENSENADA. WITH THIS SCENARIO, THE CENTRAL COAST WOULD NOT SEE ANY PRECIP FROM THIS SYSTEM, AND QUITE LIKELY THE REST OF OUR CWA WOULDN'T SEE ANY EITHER. HOWEVER, GIVEN THE CONTINUING UNCERTAINTY AND MODEL INCONSISTENCIES, WILL ONLY MODIFY THE EXTENDED BY PUSHING BACK PRECIP CHANCES BY A DAY, WHICH WOULD BE THE THURSDAY/FRIDAY TIME FRAME.
THE AVN DOES INDICATE QUITE A DEEP LAYER OF MOISTURE MOVING IN AT THAT TIME, BUT CONFIDENCE IN THIS SOLUTION IS EXTREMELY LOW, PROBABLY 1 ON A SCALE OF 1 TO 10.
I'm not faulting the folks at the National Weather Service who, I believe, do a much, much better job than we admit. They're too often judged by that one day in a thousand when an inland front backs up against high pressure and it showers on a day that was supposed to be Mostly Sunny.
But there are times when predicting the weather is easy; when they can say, days in advance, that a storm is impossible or almost certain. And then there are times like this coming week when several scenarios are possible. Personally, I find it somewhat refreshing — and surely more useful — to hear someone in a position of authority admit that they really don't know. Would that the atmosphere in Washington were such that our elected officials could say that when that's the case. Because, very often, they don't know…but they can't own up to that.