My weather "habit" is not as extreme as some. I don't chase thunderstorms, or obsessively photograph clouds (though I'm tempted to do more of the latter):

...but I do need to know what to expect. I have to plan farm work, irrigation and spray schedules. The usual stuff. Luckily, I don't have to worry about snow falling on lambs. Snow on beagles, that's another matter...

So what sort of forecasts are useful to me? In the most general sense, I like to keep an eye on the current state of the Southern Oscillation Index, an indicator of El Nino/La Nina conditions. When we get into a good El Nino, my part of the world is often very warm and dry, with strong norwesters taxing my patience and my trees. The weather pages at Fencepost, an NZ farm site (provided by Blue Skies Weather) have a seasonal summary that keeps an eye on the SOI (you have to register to get more than the two day forecast). At the moment we've got a weak El Nino developing:

"With clearly warmer than normal water in the equatorial Pacific there is now more solid evidence of a developing El Nino event. While this warming needs to continue for a few more months to confirm an El Nino, this seems very likely. At present the El Nino is rather weak, and there are no indications that it is likely to intensify greatly from its current levels through the rest of the year."

Tony Trewinnard at Blue Skies also provides Fencepost with a 12 day outlook, which is brief but helpful. Next stop is MetVUW, a weather site run by Victoria University in Wellington - also the home of some truly stunning weather pictures. They repackage the MetService rain radar (available every three hours), which helps me judge if and when rain is going to reach the farm. They also have forecast charts out to 7 days, using a US product. This gives me a good idea of what the general shape of the weather's going to be like over the coming week. Next stop (usually in early afternoon, when the day's forecast is posted) is the MetService Severe Weather Outlook. This forecast looks out to four or five days, suggesting where any "interesting" weather might pop up. That link also gives easy access to any severe weather or thunder warnings that may be active.

Putting all that information together gives me a pretty good mental picture of what the next week's weather is likely to be - in general, if not in particular. I can schedule which days are likely to be good for farm work - dry for mowing, calm for spraying etc - and which days might be better spent in the office. And it's all free. Ken Ring's almanac costs more than $40.