How to prevent your Macintosh from going to sleep and interrupting WeatherCat operations
WeatherCat works best when allowed to run at all times. If you wish to save power, quit WeatherCat before allowing your computer to go into sleep mode.
WeatherCat is also unable to process weather data properly when the macOS feature App Nap is turned on for WeatherCat. WeatherCat attempts to turn off this feature automatically but it is prudent to turn of this feature if you running into difficulty. This can be done by selecting the WeatherCat application from Finder and using the Get Info option. It will bring up the following window:
As can be seen in this example, checking the Prevent App Nap box will insure that WeatherCat will never be effected by this feature.
In principle, it should be possible to prevent your Mac from ever going to sleep by going to the Energy Saver pane of the macOS system preferences and setting Computer Sleep to Never. You can set Display Sleep to any value you choose. However, you might want to uncheck the setting: Put hard drives to sleep if possible. WeatherCat must periodically store data to your hard drive, so this setting won't save much energy and cycling the drive on and off could shorten the life of the drive. The following window shows the macOS 10.12 Energy Saver pane with the appropriate options set:
Some WeatherCat users have reported that even with the Energy Saver settings properly configured as noted above, their Mac still goes to sleep disturbing the collection of WeatherCat. This appears to be a bug in recent versions of macOS and has been tacitly verified in the December 2017 issue of MacLife magazine (page 85.) Fortunately there is a remedy in the form of a free utility called Amphetamine. It can be downloaded from the Mac App store:
Amphetamine can be configured to be more flexible. For example, you can have it running only when WeatherCat is active, but allow your computer to go to sleep when you aren't running WeatherCat. All WeatherCat users who have installed Amphetamine have solved the problem of their Mac going to sleep while WeatherCat was active.