www.ERAD2010.org ERAD in Romania!

The next European Radar Conference, ERAD 2010, will be held in Romania! A dream came true! And I know that when one wish is deep, the whole comunity of "Elfs" joins efforts to make it true.

I have met two of these Elfs in Helsinki: Jarmo and Elena.

www.erad2010.org

Insects and ground clutter

The satellite ia showing a clear sky over Romania (again a hot day) while radars (S band) intercept echoes from all kind of particles (dust, insects...) around some radar sites. Thunderstorms chasers love "bugs" because they can show the convergence lines in the wind field and other surface boundaries that can promote storms initiations. But, unexperienced forecasters can be tricked by these echoes, so is always good to first check with the satellite image.

And the reported tornado!

22 May 2008, Ramnicu Sarat
(Courtesy Antena 3)

Convergence line and severe convection

In Romania, one of the most frequent convercence line is in the SE part. In Southern circulation, with important instability, this line can bring the lift needed for convection.

12.15 UTC, 22 May 2008

Tornadic storm

A lot of good information about the case on 22 April 2008, you can find here:

http://convection.satreponline.org/cases/april08/

"Satrep" is a very good site about satellite meteorology (the best!) , enjoy!

National Mosaic

One of the radar products I am not very happy with, is the so called "mosaic", when we make an overlap of all the radars we have in the country in one single larger scale image. Is a product that can have so many erros that is very dangerous. Here, the same case like in the previous post, if you look at the SW part of the image (pinkish reflectivities over Serbia) you can see that the echoes are very strange, like a "circle" line (see zoom) , due to the contributions of two radars on the same region of the image. The beams reach different heights in the atmosphere and the composition is unreal.

The storm in Bulgaria, was tornadic, and later similar ones form over S.Romania.

and V-notch on radar

The same day, 22 April, few hours later, the same airmass that produced cells with V-shape on satellite image, also produced a High Precipitation tornadic supercell, detected by the WSR-98D S band radar in SE Romania. Doppler radial velocity image, at the bottom, has an intense mesocyclone and in the reflectivities, we can see the supercell structure, with a very pronounced "hook echo" to the S, and V-notch structure, produced by the flow splitting around a very strong updraft. Very high reflectivites, up to 70 dBZ, due to hail presence. Tornadoes were reported in Bulgaria and Romania