Hydrometcentre of Russian Federation - Russia
Severe convective storms with squall, tornado and hail in Russia are very seldom events because of geographical situation in the north part of the north hemisphere with latitude more than of 40 grads. For example it's known from publications, the maximum tornado numbers were in periods 1981-1983 and 1988-1991, by mean four tornados in a year for European part of Russia last twenty years.
It is very difficult task to recognize these events in time without dense networks of surface and other kind of observations, what we have in Russia. As local temporary and space character of these cases it's difficult also to receive any quantitative information about them. In Russia a lot of researchers try to study these severe natural events by different methods. Last years, more attention is devoted to study severe storm events and to resolve of many tasks to protect all from convective destroying damage in our country. There are the works about observation by physical new instruments and by nontraditional methods as infrasonic observation, acoustic-gravity waves observation, satellite monitoring by oceanographic spacecrafts, in Russia. But all of them are experiments. The main help with resolving many problems of monitoring convective storms now besides synoptic, radiosounding observation we should call experimental in situ data, radar network data and satellite information.
The case study of 24 July 2001 with squall-tornado events on the territory of megapolice of Moscow should be respect by Fujita classification to a weak event. The wind velocities there were about 28 m/s and thousands of unique kind of trees were destroyed. The local computer network in Hydrometcenter RF was destroyed too.
Analysis of every hour satellite images of Meteosat-7 and Meteosat-5 for 23-25 of July 2001 indicated the main cause of these hazardous convection events. The mesoscale convective complex has been generated on the north part of destroying southern (from the Mediterranean Sea) cyclone with almost north trajectory on to the territory of Russia near Baltic Sea and Latvia. The unique property of this convective complex was in their trajectory with great velocity to the east-south-east, instead of to the north-east as usually and as indicated the leading flow. And we could say there may be influence of topographical features.
The detail analysis of synoptic, aerological, radar information of this event will be presented. Besides standard observation there were possibilities to examine data of two profilers in the low atmosphere layer. The recognizing and forecasting technique of convective severe storms in European part of Russia there should be used to analysis this seldom event.