I’ve been running the Zambretti type forecaster on my site for a little while now and would like to improve it. With the amount of information that WDL puts out in the various text files it must be possible to improve the local forecast but I’m not a metereologist.
I know that generally if the baro is falling things will get worse and if it is rising thing might get better. The rate at which it rises or falls indicates possible changes in windspeed. If humidity rises above 85% we tend to get rain here.
What other key indicators should be noted to produce a better forecast, i.e. better than “partly cloudy” more like “becoming more cloudy with wind increasing from the East, rain possible later.”
here is a Q
i have a davis VP, and it produces a forecast, which is more detailed than just cloudy, etc
but, I live in the southern hemisphere
i.e you northern hemisphere people need to look at our weather map upside down and in the mirror
no joke!
i.e a SWer is like you NWer
so that means a forecast based on northern hemsiphere weather patterns will bre predicting rain coming when the wind is SW here, which is actualy generaly a clearing wind direction for us
now, getting back to the Q
it will work for a maritime climate
but places that live behind mountain ranges, or other microclimate areas/tropics, etc, it wont wont, basing things on barometer and wind direction changes
Looking at the description that Davis gives for the Vantage Pro, I would have thought it would have known about the bottom part of the planet…
Vantage Pro uses a sophisticated forecasting algorithm which takes into account not only barometric pressure, but also wind, rainfall, temperature, humidity, and longitude and latitude. The result? A much more accurate forecast.
Note the Longitude and Latitude part… did they get it wrong?
actualy, i probably have not set the latitude into the console…
but when they say latitude, they might only be refereing to the latitude within the northern hemisphere
Hmmm. Well initally I was only thinking of writing something that would improve my own local forecast but having written it for one location it should not be too difficult to build in factors to cope with other locations.
My own location a coastal town in the south-west of England with its own micro-climate which is largely dependant on wind direction, more so than Zambretti allows for. Unfortunately I don’t have access to the Vantage Pro system but I take the point about latitude, and longitude.
Leaving aside the northern or southern hemispheres for the moment - do we all not have micro-climates determined by locations like plains, mountains, coastal areas, islands and valleys? For example, in one place a lived it was normal for us to have thick fog until about 11:00 in the morning when the sun might rise to burn it off. Where I am at the moment we have what we call the Bude Triangle. We can follow rain on the radar tracking along the peninsular towards us but it will suddenly disappear about 5 miles from Bude and we stay sunny:D
Good luck and let us know how you get on. When I have a bit more time free I’m going to try to work out my local ‘rules’ and see if I can come up with a decent local forecast, so please post any hints & tips you come across.