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    On February 21 a quite rare event took place near Shoeva in the western Judean Mountains, 20 kilometers west of Jerusalem. A single thunderstorm produced a tornado, when the chances of severe storms were very low. In fact, the tornado producing storm was the only storm that developed that day in Israel.

    A large area of low pressure came down from Russia towards Turkey on Wednesday, February 18. The warm front pulled a Red Sea Trough towards the Middle East, which connected to the low, now in north-eastern Syria, on Thursday February 19. That caused the formation of scattered storms in Israel, and the forecast was for more storm development until Friday. But on Friday the low pressure became weaker, and the Red Sea Trough retreated southwards. The chances for severe weather, or any weather at all, were becoming very slim. On Saturday, February 21 the small low pressure was still around, now in eastern Jordan. It was still connected to the Red Sea Trough, but the conditions were not quite right for classic severe storm development in Israel. The forecast said nothing about any chances for severe weather, but I still had my hopes up. A Red Sea Trough is very hard to forecast, and on more that one occasion in the past the forecast was completely wrong...

    Already in the early morning of Saturday, February 21 I saw towering cumulus developing in western Jerusalem. Jerusalem itself was clear, so I figured the best place to be was west of Jerusalem. In 11:30 I went to Har-Adar, one of the highest mountains in the area, and saw towers forming above the area where the Judean Mountains were starting to rise from the plains of central Israel, while the other areas were completely clear. By 13:30 the sky was cloudy. I drove to the western-most edge of the Judean Mountains, near the small town of Shoeva, 20 kilometers west of Jerusalem. From there I had a good view of the plains and the Mediterranean coast, where I saw that the weather was sunny. In 15:00 an area in the clouds above me became darker, and large rain drops began falling. I noticed a wall cloud about 50 meters to the north, where the severe thunderstorm had developed unnoticed among the other clouds. I couldn't see the storm structure because of the clouds, but the wall cloud and updraft base were ominous enough for me. 2 minutes later a downburst of marble-size hail started, which lasted for about 35 minutes. I couldn't see the wall cloud, and at that moment I thought that this will be everything this small storm had to offer. I got into my car and started to drive away from the storm to avoid the hail, when I took a quick glance above me, just to make sure I wasn't missing something. And what I saw took me completely by surprise - A rapidly rotating funnel just 40 meters away, 1/4 of the way to the ground! I never thought I'd see a tornado when I woke up that morning... I quickly took the video camera and started filming the funnel, which was getting wider, but not lower. The hail completely stopped, and everything was quiet, except the wind... I took some photographs too, and I noticed that the cloud around the funnel started rotating. Suddenly the funnel started to lower, and rotation increased. A tornado formed, but it began to retreat after about a minute. 4 minutes later the tornado roped and almost completely disappeared. Another funnel became visible again 2 minutes later, but it lasted for about 3 minutes. There was still cloud rotation afterwards, but then it stopped too, and hail began falling again. The entire tornadic event took about 20 minutes. 10 minutes later another wall cloud formed but soon disappeared. I stayed in the area for about an hour just to make sure nothing else is going to develop, and I drove home, very happy after a surprisingly succesful chase.

    The possible answer to the question why a severe storm developed near Shoeva in the Judean Mountains, was the wind direction. The trough was east of Israel, so the winds were coming from the WNW. Humidity entered Israel from the Mediterranean Sea, and as it hit the mountains of central Israel clouds developed, and because of the presence of the Red Sea Trough (even though it was week) the atmosphere was conditionally unstable. The clouds continued to develop, while the rest of Israel remained completely sunny. A cold low pressure in high altitude was probably the cause of the severe nature of the storm. During the next days I will collect as much data as possible from the Meteorological Service of Israel and try to understand the exact cause of this rare and fantastic event.