<div class="eI0">
  <div class="eI1">Modelo:</div>
  <div class="eI2"><h2>COSMO (Consortium for Small-scale Modeling)</h2></div>
 </div>
 <div class="eI0">
  <div class="eI1">Actualizado:</div>
  <div class="eI2">27 times per day, from 00:00, 03:00, 06:00, 09:00, 12:00, 15:00, 18:00, 21:00 UTC</div>
 </div>
 <div class="eI0">
  <div class="eI1">Tiempo medio de Greenwich:</div>
  <div class="eI2">12:00 UTC = 06:00 MGZ</div>
 </div>
 <div class="eI0">
  <div class="eI1">Resoluti&oacute;n:</div>
  <div class="eI2">0.0625&deg; x 0.0625&deg;</div>
 </div>
 <div class="eI0">
  <div class="eI1">Par&aacute;metro:</div>
  <div class="eI2">Maximum wind velocity of convective wind gusts</div>
 </div>
 <div class="eI0">
  <div class="eI1">Descripci&oacute;n:</div>
  <div class="eI2">

The method of Ivens (1987) is used by the forecasters at KNMI to predict the
maximum wind velocity associated with heavy showers or thunderstorms. The
method of Ivens is based on two multiple regression equations that were
derived using about 120 summertime cases (April to September) between 1980 and 1983.
The upper-air data were derived from the soundings at De Bilt, and
observations of
thunder by synop stations were used as an indicator of the presence of
convection.
The regression equations for the maximum wind velocity (w<sub>max</sub> ) in m/s
according
to Ivens (1987) are:<br>
<ul type="square">
<li>if T<sub>x</sub> - &#952;<sub>w850</sub> &lt; 9&deg;C
<dl>
<dd>w<sub>max</sub> = 7.66 + 0.653&sdot;(&#952;<sub>w850</sub> - &#952;<sub>w500</sub> ) + 0.976&sdot;U<sub>850</sub><br></dd>
</dl>
<li>if T<sub>x</sub> - &#952;<sub>w850</sub> &ge; 9&deg; C</li>
<dl>
<dd>w<sub>max</sub> = 8.17 + 0.473&sdot;(&#952;<sub>w850</sub> - &#952;<sub>w500</sub> ) + (0.174&sdot;U<sub>850</sub> + 0.057&sdot;U<sub>250</sub>)&sdot;&radic;(T<sub>x</sub> - &#952;<sub>w850</sub>)<br></dd>
</dl>
</ul>
<br>
where 
<ul>
<li>T<sub>x</sub> is the maximum day-time temperature at 2 m in K
<li>&#952;<sub>wxxx</sub> the potential wet-bulb temperature at xxx hPa in K
<li>U<sub>xxx</sub> the wind velocity at xxx hPa in m/s.
</ul>
The amount of negative buoyancy, which is estimated in these
equations
by the difference of the potential wet-bulb temperature at 850 and at 500 hPa,
and horizontal wind velocities at one or two fixed altitudes are used to estimate
the maximum wind velocity. The effect of precipitation loading is not taken into
account by the method of Ivens.
(Source: <a href="http://www.knmi.nl/" target="_blank">KNMI</a>)

    
  </div>
 </div>
 <div class="eI0">
  <div class="eI1">COSMO-DE:</div>
<a href="http://www.cosmo-model.org/" target="_blank">COSMO</a> <br>
  <div class="eI2">The COSMO-Model is a nonhydrostatic limited-area atmospheric prediction model. It has been designed for both operational numerical weather prediction (NWP) and various scientific applications on the meso-β and meso-γ scale. The COSMO-Model is based on the primitive thermo-hydrodynamical equations describing compressible flow in a moist atmosphere. The model equations are formulated in rotated geographical coordinates and a generalized terrain following height coordinate. A variety of physical processes are taken into account by parameterization schemes. <br> The basic version of the COSMO-Model (formerly known as Lokal Modell (LM)) has been developed at the Deutscher Wetterdienst (DWD). The COSMO-Model and the triangular mesh global gridpoint model GME form – together with the corresponding data assimilation schemes – the NWP-system at DWD, which is run operationally since end of 1999. The subsequent developments related to the model have been organized within COSMO, the Consortium for Small-Scale Modelling. COSMO aims at the improvement, maintenance and operational application of the non-hydrostatic limited-area modelling system, which is now consequently called the COSMO-Model. </b>
</div></div>
 <div class="eI0">
  <div class="eI1">NWP:</div>
  <div class="eI2">Numerical weather prediction uses current weather conditions as input into mathematical models of the atmosphere to predict the weather. Although the first efforts to accomplish this were done in the 1920s, it wasn't until the advent of the computer and computer simulation that it was feasible to do in real-time. Manipulating the huge datasets and performing the complex calculations necessary to do this on a resolution fine enough to make the results useful requires the use of some of the most powerful supercomputers in the world. A number of forecast models, both global and regional in scale, are run to help create forecasts for nations worldwide. Use of model ensemble forecasts helps to define the forecast uncertainty and extend weather forecasting farther into the future than would otherwise be possible.<br>
<br>Wikipedia, Numerical weather prediction, <a href="http://en.wikipedia.org/wiki/Numerical_weather_prediction" target="_blank">http://en.wikipedia.org/wiki/Numerical_weather_prediction</a>(as of Feb. 9, 2010, 20:50 UTC).<br>
</div></div>
</div>