Finnisch für Anfänger: SYYSSUMU
SUMU = Nebel / fog
SYKSY = Herbst / autumn
SYYS = SYKSY poetisch (SYYSKUU = September)
SYKSYINEN = herbstlich / autumnal
All airliners would say fog = delay. Fog = delayed arrivals, delayed passengers, delayed departures, lost connections, long waiting lines, stressed airliners.
In aviation, fog normally prevents aircraft from taking off or landing at airports other than those equipped with an Instrument Landing System. Fog can be especially deceptive for light aircraft because often they will overfly the airfield to assess the surface conditions before landing. When the pilot is looking straight down at the field, he will usually be looking through only about 100 or 200 meters of fog. If the fog is thin enough, the pilot will be able to see the runway with a minimal amount of interference. However, when the pilot lines up for the final approach phase, instead of looking vertically through the fog, he will be looking through it at an angle, thus increasing the amount of haze he has to see through, often completely obscuring the runway. This presents a hazard, because the pilot may think that the visibility is (or soon will be) suitable for landing when it is not. (Wikipedia)
And after the foggy season is gone the snowy season will come.