One of my two classes this term (Quantum Optics) is a junior/senior level elective, and when I teach those sorts of classes, I like to invite the students over to the house for dinner (they're paying $40K/year for the Liberal Arts College Experience, after all...). The problem this year is that it's also a very large class-- 17 studnets, almost unheard-of for a class at that level. Our house doesn't have room to hold 17 students. We barely even have 17 chairs.
This isn't a problem, as long as they can be outside, which is what I prefer, anyway-- I usually make spiedies on the grill, and the clean-up is easier if everyone can be outdoors. So, the scheduling of the event becomes dependent on the weather.
Last week, I sent out an inviation for tonight, the Monday of the last week of classes (the fact that it happens to be Memorial Day is a coincidence-- we don't get the day off or anything). The advance forceasts called for good weather (my father in Mr. Weather Channel, and keeps me informed), and there's an Admissions event scheduled for today, which usually guarantees a sunny day. For the last five days, the forecast for today has remained the same: partly sunny, mid 80's.
I wake up this morning, and it's raining. Yahoo has revised their forecast to:
Scattered thunderstorms this morning, then partly cloudy during the afternoon hours. A few storms may be severe. High 84F. Winds W at 5 to 10 mph. Chance of rain 60%.
Tomorrow, which I've held out as a rain date, looks even worse. If you believe that they publish these forecasts for anything other than comedy value, that is.
It's rather unfair to knock meteorologists for failing to give accurate forecasts. For a start, weather is complex. Weather cells can be localised and chaotic. Moreover, weather forecasts have improved immeasurably over the past 40 years. We might bitch because they revise them, but I'd rather they did that than not. And their accuracy is actually very high - but of course we note the forecasts that fail and blur together the many forecasts that succeed.
Come to Australia. The forecasts here are accurate in the extreme. I live in the subtropics so we get these very localised cells that dump rain, thunder and occasionally hail, but even then we get a probability estimate that is pretty good, and what's more you can log onto the weather radar to check where the rain is, which I bet you can do there.
Anyplace nearby where you can rent a tent PDQ?
Meteorologists main raison dÂ´Ãªtre is to make economist prediction skills look good.
I find that the weather forecast depends on the source to which you turn, with different websites, radio stations, and TV channels giving different projections.
'Forecasters' (to use the usual misnomer) communicate, sharing out the most probable weather options between them and rotating their projectionms. This gives them a half-decent hit rate, and they rely on confirmation bias to persuade people that their projections are better than mere educated guesswork.
I know this for a fact (I had a mate whose brother (or cousin?) works for the BBC weather department).