Verification

I download the site specific NWPNWP Numerical weather prediction uses mathematical models of the atmosphere and oceans to predict the weather based on current weather conditions. data that resides in the HTML the Met OfficeUKMO The Meteorological Office is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy weather application requests whenever anyone looks for a forecast for a location for a number of my applications I’ve written to visualise the forecast data in a table, graph or on a map. Parsing the data was a tricky business, but I persevered, and can now grab a week of one and the three hourly data for any number of elements including temperature.
As well as visualising the data, I thought it might be interesting to do a spot of forecast verification by comparing the three hourly forecast data with the actual values from SYNOPSYNOP SYNOP (surface synoptic observations) is a numerical code (called FM-12 by WMO) used for reporting weather observations made by manned and automated weather stations. SYNOP reports are typically mad hourly and consist of groups of numbers (and slashes where data is not available) describing general weather information, such as the temperature, barometric pressure and visibility at a weather station. observation for any location in the world.
I know that the forecast values although quite accurate, are far from being spot on. The question I was intrigued to find out was just how accurate they are. Here are some recent preliminary results I have produced from the add-on to my UKMOUKMO The Meteorological Office is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy NWP application I wrote a number of years ago.

Notice the very warm day on the 6th of April associated with storm Kathleen, and how underestimated temperatures at Kinloss were because of a slight foehnFoehn A foehn, is a type of dry, relatively warm, downslope wind that occurs in the lee (downwind side) of a mountain range. It is a rain shadow wind that results from the subsequent adiabatic warming of air that has dropped most of its moisture on windward slopes (see orographic lift). As a consequence of the different adiabatic lapse rates of moist and dry air, the air on the leeward slopes becomes warmer than equivalent elevations on the windward slopes. effect.

Generally a pretty good result with temperatures +/- 2°C at Heathrow.

Again at Exeter temperatures within +/- 2°C of the forecast, although it didn’t do well with some of the minima, and the 8th of April was a bit of a disaster because heavy rain suppressed temperatures.

I’ve noticed that recently the Met Office are in the process of updating the NWP data their app uses, so they must have some concerns themselves about its accuracy, although the changes in the NWP might have more to do with forecast weather, rather than forecast temperatures. At the moment I am still using the old data and haven’t switched to the new trial data. In the meantime, let me know about what you think about the accuracy of the forecasts the Weather App produces in your area. I’ve still got a bit more testing, tweaking and bug fixes to do to my verification application, but I’ll keep you posted.😉