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1

My first observation upon looking at the picture was that Typhoon In-fa (the southernmost one in the picture) nearly stalled prior to making the right angled turns in its path. There is a clustering of very closely spaced location markers for the dates 19 and 20 July, prior to the first 90 degree turn and then again for the dates 22 to 24 July at the time of ...


0

Not sure if I'm misunderstanding your question. As stated in the article you referenced, the reason you don't get rained on 50% of the time when the forecast says 50% PoP is because you are much smaller than the size of the model grid-cell. 50% PoP means it could rain anywhere in that grid-cell (usually something close to 10km x 10 km area). If the PoP ...


5

If there was a worldwide standard, then WMO would have imposed it to its members. Here are the definitions in the American (NOOA/NWS) standard: http://www.njweatherscan.com/definitions_of_precipitation.htm Light rain: falling rate of less than 2,54 mm/h. Moderate rain: falling rate of more than 2,8 mm/h, but less than 7.6 mm/h. Heavy rain: fallin rate of ...


4

The German Weather Service (Deutscher Wetterdienst, DWD) provides the following definitions: Heavy rain is defined as large amounts of precipitation during a fixed period of time. [...] The DWD issues warnings of heavy rain using three categories: heavy rain: 15 to 25 l/m² within 1 hour or 20 to 35 l/m² within 6 hours severly heavy rain: 25 to 40 l/m² ...


0

Fun fact about rain percentages. When it says there is a 70% chance of rain, it does not always mean there is a 70% chance that you personally will get rained on. Weather stations are divided into sections. Depending on what app you use some predictions can be interpreted differently. But most of the time the 70% chance of rain means that there is nearly a ...


6

The Virtual tour is good, and I don't know why that wasn't an accepted answer. So I'll throw my answer into the ring. I'll recommend you try the NWP and Forecasting Comet module (it's free if to get an account). That'll probably help more than my answer, which is based around the forecasting classes that I took and my experience as a forecaster in the ...


5

The National Weather Service actually has a nice forecast summary page that answers your question: Our scientists thoroughly review current observations using technology such as radar, satellite and data from an assortment of ground-based and airborne instruments to get a complete picture of current conditions. Forecasters often rely on computer programs to ...


2

Weather prediction has been (https://www.ecmwf.int/en/newsletter/166/news/forecast-performance-2020) and will be getting better, but it can only get so good. Even if we build the perfect weather model and feed it with the perfect initial and boundary conditions (practically impossible at the moment), the forecasts will still be overshadowed by chaos and/or ...


4

You are expecting too much. Weather forecasting has become quite reliable. There are exceptions. One exception is predicting what will happen more than seven days into the future. At ten days into the future, forecasts remain pretty much a random guess. The 1960s discovery that weather is chaotic (Predictability: Does the flap of a butterfly's wings in ...


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