Due to its proximity to the sea and its high elevation Mount Olympus demonstrates unique weather patterns. During the summer months the dominance of cumulus type clouds is typical as the moisture from the sea to the east and from the valley of Elassona to the west rises violently above the summits of the mountain creating afternoon thunder storms.

During early season (May - June) when the upper atmosphere is still cold considerable amounts of hail prevail the scenery and depending on the isothermal elevation, hail sometimes can reach the size of cherries. Thunder storms are the result of moisture availability and big temperature gradients between the upper and lower mountain.

During early summer it has been observed many times for some people to be swimming in the sea, while other to be struggling with snow and hail on the upper mountain.

Due to this typical summer weather pattern is highly advisable that all activities (climbs to the top, rock climbing on the big alpine faces, etc) to be taking place early in the morning.

As the summer gives place to the autumn and subsequently to winter weather is generally stabilized and more predictable as the summer thunderstorms recede. Stable does not always means good weather but refers to long periods of the similar weather. For example it can rain for many consecutive days during October or it can be sunny and dry for an equal amount of time. In general, Mount Olympus receives fronts from all directions:

Northeast and northwest, translated into cold but stable weather. Northeast fronts can be windy with low wind chill temperatures
Southwest, wet and usually windy weather
South, rainy with winds exceeding 100km/h. 

Precipitation on Mount Olympus demonstrates an irregular spatial distribution during the summer, a result of the irregular pattern of thunderstorms.
Data collected from the Aristotle University of Thessaloniki Meteorology Department between 1962 and 1970 suggest the following annual precipitation spatial distribution:
1350mm in Stavros
   road from Litochoro to Prionia - elevation 960m
1490mm at Prionia
   end of the paved road, elevation 1060m
1700mm at Agios Antonios summit
    elevation 2815m
(Data redistributed from Kostas Tsipiras book: Olympos)
Precipitation on the upper mountain is difficult to be measured as it is often characterized by high winds.

Another regular phenomenon observed during the fall and the winter months is that of temperature inversions. There have been many times when it is raining and/or snowing at the trailhead while on the higher mountain to be sunny, still and warm. Many climbers have been fooled by this special weather phenomenon.

Weather forecasting for Mount Olympus is provided by many and websites. Following a 10-year experience of calibrating the forecasts provided by many institutions we site the most accurate ones based on objective on-site monitoring.

Websites are listed from a regional to the local scale, the combination of which can greatly aid potential ascents.
Medium weather forecast for Europe. Provides forecasting for precipitation, temperature and moisture. Also includes two-week forecasting.
University of Athens SKIRON weather forecasting model. Referring to Greece being accurate for the fall and winter months. Summer thunderstorms are often hard to predict. Displays many different meteorological parameters.
One of the most accurate websites for Mount Olympus weather. Give forecast for various elevations.
Greece's National Meteorological Society weather forecast website. Accurate and detailed. Provides useful information about hailstorms as well as many historical data and observations.
Instead of being used by the technology it should be wise that we use technology for have a better estimate about the weather during climbing, making in this way the climb on Mount Olympus safe and enjoyable.  


Cumulus type clouds characterize the afternoon weather patterns during the summer months. 
Photo: Mike Styllas

Wintertime temperature inversion. Under the cloud blanket there was light snowfall prohibiting climbers to start their climb. 
Photo: Mike Styllas