What is an opposing wind layer?
Wind at launch level blowing from roughly the opposite direction to the surface (10 m) wind. After take-off you fly into the opposing flow and shear, so the risk of a sink rises.
FETHIYE · OLUDENIZ · BABADAG
Opposing wind layers and northerly flow aloft
At Babadağ the wind at launch level and the wind at the surface do not always blow from the same direction. If they oppose each other, a sink after take-off is possible; with strong northerly flow aloft, a land breeze can appear at the evening landing. The two warnings on the site were added to catch these two cases.
Layer conflict: 29 September
Around 17:00 on 29 September 2026, take-offs from 1800 met a sink after launch. At the same hour the model wind at launch level (800 hPa) was from the north-east and the surface wind from the south-west: the two layers opposed each other and both were weak. Air that sits under the sea breeze at the surface meets the opposing flow and shear above after take-off.
The site shows this as Confirm on site with the reason "upper and surface wind opposed". Conditions: at least 120° between the two layers, at least 4 km/h of wind in both and no strong thermal (below 2 m/s).
Northerly flow aloft: 28 September
On the afternoon of 28 September 2026 the model wind at 800 hPa was 19–40 km/h from the north. When the sea breeze faded at 17:00 this northerly flow started as a land breeze at the landing area and flights stopped. The northerly wind aloft had shown this event hours ahead.
On the site, if wind at 800 hPa from 320°–60° is 20 km/h or more, landing shows Risky from 15:00 local (default threshold) and the decision carries over to that hour's launches.
The effect of cloud: 5 October
Besides wind, cloud also decides which launch is used. On 5 October 2026 the cloud base was about 1,400 m, flights continued from 1200 and the high launches stayed in cloud. See the forecast-reading guide.
What to do
When you see a warning, ask the launch marshal and use local observations; the model runs on a grid of about 7 km and cannot fully see slope flow. Also watch the direction and change of the wind at the landing area before you launch. About land breeze: land breeze and landing safety.
Why is northerly flow aloft a landing warning?
When the evening sea breeze fades, the northerly flow aloft can descend to the landing area as a wind from land to sea; the landing is then made with a tailwind and gets harder.
Related pages
How to read the launch forecast · Land breeze and landing safety · Meteorology guide · Frequently asked questions
Page text last updated: . This page is informational. The flight decision is made on site by the pilot, the launch marshal and the Fethiye Slot Service Centre. Fethiye Slot Service Centre (SHM) ↗