5 ms·
Ok ... I am directly going to piggyback on this: 1. Subjectively this years weather predictions have been way off, compared to the years before. I heard severa
by fho 5y ago
Ok ... I am directly going to piggyback on this:
1. Subjectively this years weather predictions have been way off, compared to the years before. I heard several theories on that: (a) the year was extraordinary (less cars, less flights) and (b) predictions were worse because data from plane based weather radar was missing.
-> Does anybody know if my subjective feeling is based in reality? And if true, what are the reasons?
2. Again subjectively, but I feel like most of my weather based decisions are "do I leave now or do I wait for the rain to pass". That question is answered pretty well by looking at the weather radar maps myself. I feel like an statistical/ML/AI approach that combines what was the weather yesterday and what is the weather in the surrounding cities should fair pretty well.
- joosters 5y ago1. The data I scrape could be enough to check this theory out. Currently the site calculates a 'all time' accuracy and 'last year' accuracy, it would be fairly simple to also add an accuracy for 1 year back, 2 years back, etc. When I have time, I'll give that a try. 2. I once knew of a website that did just this - it displayed the radar image for the village that the creator lived in, and used some really simple linear motion estimation to predict rain in the next hour. I believe it had pretty good accuracy, but unfortunately I can't find that site any more, sorry.
- ac29 5y ago> (b) predictions were worse because data from plane based weather radar was missing Is plane based radar even used for forecasting? I cant think of what advantage it would have over satellite and ground based radar, with the possible exception of data gathered midocean (where land radar doesn't exist, but there also arent many people).
- counters 5y agoSort-of; it's really the TAMDAR [1] system taking measurements of humidity and temperature that are readily assimilated into the global forecast models run by all of the major weather forecast centers (NOAA, UKMO, ECMWF, etc). These observations play a non-trivial role in improving the assimilated initial conditions and boosting forecast quality. Recent work [e.g. 2] has demonstrated that the degradation in availability of aircraft-based observations during the pandemic likely did produce a real, statistically significant decrease in average forecast skill during the afflicted time periods. [1]: https://www.nasa.gov/vision/earth/environment/2006ams_TAMDAR.html https://www.nasa.gov/vision/earth/environment/2006ams_TAMDAR... [2]: https://journals.ametsoc.org/view/journals/apme/59/11/JAMC-D-20-0010.1.xml https://journals.ametsoc.org/view/journals/apme/59/11/JAMC-D...
- joosters 5y agoHere are the accuracy stats broken down by year, for the last ten years: https://weather.slimyhorror.com/tenyears.html https://weather.slimyhorror.com/tenyears.html 'Last year' = last 365 days, '2 years ago' = the 365 days before then, etc etc For most places, it does seem that this last year's weather forecasts have been worse.
- fho 5y agoVery nice! Apparently this topic was actually researched: https://news.ycombinator.com/item?id=28749131 https://news.ycombinator.com/item?id=28749131