Same here. Already did an uninstall and reinstall of omweather and first it worked but then when I switched two cities from gismeteo.ru to weather.com it crashed again. Might be because one of them has a slash in its name in weather.com and hasn't in gismeteo.ru. But not for sure if that's the reason.

Also don't know where the config file is stored.

It might be related to some gtk stuff as there were several warnings in syslog yesterday. Maybe all crashed widgets use some kind of gtk and therefore also crash.