Venting re long term weather predictions

[rcnaylor]

First, our weather guys are usually fairly close on the 2-3 day forecast. So, I give them credit for getting quite a bit better, it seems to me, on that over the last 20 or 30 years.

My gripe is the 2 to 6 month forecast. Now, I don't expect them to tell me today that its going to rain two months to the day from now. I'm talking big picture. Is it going to be "wet", "dry", "hotter than average, colder than average"

They really don't seem to be much on that, at all.

For instance. Last year, here, they predicted normal to maybe a little drier than normal. We broke all kinds of records for historically dry and historically hot. Zero prognistication that kind of stuff was coming.

A few months ago, they sadly reported the Pacific waters were warming back up so we could expect what we usually get from a la nina pattern through the winter months here, warmer and drier (this prediction while we were already in a historically dry drought).

So, what do they start saying in the last week or 10 days about all the pacific fronts that have been lining up and coming through here keeping us in weather more akin to Seattle (didn't see the sun for over a week)... other atmoshpheric forces are over riding the la nina affect to cause a pattern more generally associated with El Nino (a cooler wetter pattern for us).

Argh. Just get close if you're going to claim what the weather will be like 2 to 6 months out. (The NWS actually has predictions that go out 18 months, but, I don't even look at those they seem of such little value.)

I mean really, in this day and age is getting close on the big stuff so unreasonable to ask?

On a more practical level, if we don't understand big picture weather any better than that, why do we want to put anyone in charge of trying to change the effects of global warming (with various man made things like coating roofs white, seeding the ocean, etc.)?

PS Four inches of snow predicted for Monday in this period widely predicted as warmer/drier a few weeks ago. Ballpark guys, ballpark!

[MorpheusPA]

I mean really, in this day and age is getting close on the big stuff so unreasonable to ask?

Yes, chaos. Unless you know the exact starting conditions, the ending condition is unpredictable for any given location. Our weather is a chaotic system with fierce negative feedback (AKA the Sun) so although very general trends are predictable ("Winter will be colder than summer barring massive disturbance") long-range forecasts tend to be, well, wrong.

Even so, an unpredictable change (like Krakatoa blowing up) would render any forecast made immediately invalid across the entire globe.

On a more practical level, if we don't understand big picture weather any better than that, why do we want to put anyone in charge of trying to change the effects of global warming (with various man made things like coating roofs white, seeding the ocean, etc.)?

This is why I'm not a fan of rampant geo-engineering. However, given that we already did that, reverse engineering may become necessary. You should not expect the results to be predictable in any given locale, however, over the long-term.

[rcnaylor]

Ah, meant to put this in the Water Cooler.

Oh, well, I agree, the day may come when its clear we've messed up global warming enough we have to try to undo some of the problems. But, boy,I have no confidence we know enough to start trying to manipulate the weather/climate world wide.

Places were we've really tried to manage an environment over decades, like some of our national parks, (Yellow Stone, the Colorado River) have come with big learning pains (oh, fire is needed ever so often, floods keep ecosystems working, etc.)

[dss]

For fun, a long time ago, I kept track of the 5 day forecast every day as well as the actual high and low. Not surprisingly, each day out was a bit more variable and tended towards predicting the mean temperature for that day. So I agree with the above, the temperature for any next day is some function of the average and a prediction based on the weather patterns heading your direction and an amount of variation which increases the further you go out.

I'd settle if we could just get a dry day to mow every once in a while

[andy10917]

I've noticed that when the meteorologists in general get serious about a problem with accuracy, the data models and forecasts get better and better over the course of time. The issue is that it takes a l-o-n-g time to get measurably better - like twenty years. Owning a place right at the water in Key Largo, FL has illustrated this big-time to me. The accuracy of hurricane landfall predictions is WAY better today than it was ten or twenty years ago. And Nor'easters were a surprise phenomena twenty years ago in the northeast - they sprang up off the DELMARVA. Now they can predict them a week in advance, way before they even form. But long-range forecasting is probably well into our future - every minor variation from a general model affects everything after it.

[rcnaylor]

Well, while we are postulating "out there" a bit, it seems to me that we have a fairly good grasp on the things that actually trigger storms and weather patterns. So, think we'll ever be able to come up with ways to artificially trigger and/or affect things?

Create a windfunnel into the upper stratosphere that starts a low pressure area? Build something that creates a high pressure ridge, where we want it when we want it? Of course, nature does it with little things over huge areas (like a little more sun on the Pacific Ocean or less circulation off SE Asia. I don't see us doing things on that scale any time soon. But, enough to maybe change things some? Put a "low pressure machine" off San Diego to scale back a historic drought in the Southwest?

Of course, if we could, I suspect picking who to help, and "hurt" in some ways, would be a pretty touchy political thing too.

[MorpheusPA]

Well, while we are postulating "out there" a bit, it seems to me that we have a fairly good grasp on the things that actually trigger storms and weather patterns. So, think we'll ever be able to come up with ways to artificially trigger and/or affect things?

Yes, we already have. Want to stop a hurricane? Trigger a ring of nuclear bombs in the eyewall.

Nobody really wants to go there, but it should work.

Energy inputs to start or stop a system would be similarly large (or larger) for anything else. And given the unpredictability of what you're doing, nobody wants to go there either. You might stop the hurricane, but set off one that's worse later on.

Or pass a tipping point in that locale and set off something like a hypercane. Bad move.

To a lesser extent, we can slightly influence the weather. Silver iodide is unreliable, but can turn a 90% chance of showers to 95%.

We already have high-pressure generators; they're called cities. But the force of the weather is so much greater than our human efforts that it still rains in them--the high pressure is pretty easy to disperse.

[BuckeyeChuck]

I don't believe in the accuracy of the long range forecasts. I have a "weather station" that constantly displays a seven day forecast from Accuweather. That seems to be about the best source I have found to date.

NOAA weather does seem to be doing a good job as far as weather "alerts" and "Warnings" go when they activate the weather radio. The forecast they give always seems to be hedging to me though. Accuweather seems more definitive.

[texasweed]

There is no accuracy to any long term weather forecast. The two top climatologist in the USA William Gray and Phil Klotzback of CU jointly announced they will no longer issue seasonal Hurricane forecast.

Bill and Phil have also had all his government funding cut-off for their views Man Made Global warming by publicly stating Man Made Global Warming was a hoax invented by the UN to extort money out of developed western countries, and a conspiracy to create 1-world government.

[Jackpine]

NOAA weather does seem to be doing a good job as far as weather "alerts" and "Warnings" go when they activate the weather radio. The forecast they give always seems to be hedging to me though. Accuweather seems more definitive.

Hedging is a good description of NOAA/NWS weather forecasts. My local NWS site does that a lot but there are a lot of uncertainties in forecasting weather in the Great Lakes region. Many seasoned weathermen have stated our area is the hardest to forecast in the country. On the other hand, when it comes to forecasting lake effect snow amounts and where the heaviest bands of snow are likely they do a very good job.