Predict Weather, Divination

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koewn-admin
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Joined: 2015-03-12 14:14
Predict Weather, Divination

I'm gonna be asked about Predict Weather, I think. Today's base expectation is ye olde' 10-Day Forecast, available damn near everywhere.

So, with some light Googling:

Predict Weather gives you the next 12 hours in a 1 mile/level radius, accurately.

Internet tells me that, generally, next-day forecasts are ~95% accurate, for temperature at least.

Divination, if used on something so boring as the weather, gives us a 60% + 1%/level base chance for a correct answer.

Internet tells me that 5-day forecasts might be something like 77% accurate, so 5 day forecasting technology is a pretty high level diviner.

Doubling that drop, I might pretend that 10-day forecasts would be ~30% accurate.

So...I'll pick a fortnight, 14 days, as the max range, as that fits nicely with max level. I'll end it at ~5% chance at 14 days for the 1st level caster, being the equiv. of a natural 20. If I take those points and apply a bit of a modified quadratic fitting:

Rounded % Base % Days Out @7th @14th
97% 97.20% 1 104% 111%
91% 90.93% 2 98% 105%
85% 84.52% 3 92% 99%
78% 77.96% 4 85% 92%
71% 71.27% 5 78% 85%
64% 64.44% 6 71% 78%
57% 57.47% 7 64% 71%
50% 50.36% 8 57% 64%
43% 43.12% 9 50% 57%
36% 35.73% 10 43% 50%
28% 28.20% 11 35% 42%
21% 20.54% 12 28% 35%
13% 12.74% 13 20% 27%
5% 4.80% 14 12% 19%

we may or may not have something that could approximate today's weather prediction technology, which may be indistinguishable from magic.

No idea what level that'd be - a limited range divination that can only ask about 1 particular unavoidable, and unchangeable, thing?

 

 

Lebron Soldiers XI 11