Fog can be forecast successfully and accurately, but it is not possible to determine in advance what the visibility will be at every point along the 400-kilometer Trakia Motorway between Sofia and Burgas. This would require additional equipment and enough specialists, climatologist Simeon Matev explained on NOVA’s “Wake Up” program.
“Fog can be forecast very successfully and accurately. There are a number of established methods for forecasting it, and in Bulgaria it is forecast very accurately,” Matev said. According to him, the difficulty stems from the road’s considerable length and the differences in conditions along its various sections.
The River and Cooling Air Are Key Factors
The area where the fog formed during the tragic incident is among the places where this phenomenon occurs frequently. The Tundzha River runs nearby, and under suitable conditions its moisture quickly saturates the air.
“On Tuesday, when the incident occurred, the problem was that it rained during the night, adding even more moisture. Then the skies cleared, the air began to cool, and the combination of moisture and cooling air always leads to fog,” the climatologist pointed out.
Thus, a forecast can take into account the likelihood of fog in a particular area, but the specific visibility on an individual section depends on local conditions and can change over a short distance.
Data on Accidents in Fog
Matev also commented on studies from the United States. According to the data he cited, 1% of crashes occurred in fog, while fatalities accounted for 2%. He clarified that these figures do not necessarily identify fog as the cause of the accidents, but indicate that they occurred under such visibility conditions.
As examples, the climatologist cited a pileup involving 156 vehicles in the state of Louisiana in 2023 and an incident in Hungary three years ago, in which 49 vehicles collided. According to him, the number of victims in both cases was much lower compared with the incident in Bulgaria.
Sources: nova.bg