<div class="eI0"> <div class="eI1">Model:</div> <div class="eI2"><h2><a href="http://www.emc.ncep.noaa.gov/gmb/gdas/" target="_blank">GDAS</a>: "Global Data Assimilation System"</h2></div> </div> <div class="eI0"> <div class="eI1">Updated:</div> <div class="eI2">4 times per day, from 00:00, 06:00, 12:00 and 18:00 UTC</div> </div> <div class="eI0"> <div class="eI1">Greenwich Mean Time:</div> <div class="eI2">12:00 UTC = 07:00 EST</div> </div> <div class="eI0"> <div class="eI1">Resolution:</div> <div class="eI2">0.25° x 0.25°</div> </div> <div class="eI0"> <div class="eI1">Parameter:</div> <div class="eI2">Kind of precipitation</div> </div> <div class="eI0"> <div class="eI1">Description:</div> <div class="eI2"> <table width="450" cellspacing="0" cellpadding="3" border="0"> <tr><!-- Row 2 --> <td align="left" width="180" height="138"><img src="//www.woweather.com/daten/expertgifs/precipkind_map1.gif" alt="kind of precipitation"></td> <td align="left" width="10" height="138"> </td> <td align="left" valign="top"><font face="Arial,Helvetica" size="2">Rain or shower? This chart shows the kind of precipitation that is likely to fall given the atmospheric and surface conditions at a certain place. <br><br>The following table explains the symbols: </td> </tr> </table> <br> <table border="0" cellpadding="0" cellspacing="1" width="450" height="195"> <tr> <td width="32%" height="18" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Precipitation</td> <td width="22%" align="center" height="18" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Light</td> <td width="23%" align="center" height="18" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Moderate</td> <td width="23%" align="center" height="18" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Heavy</td> </tr> <tr> <td width="32%" height="25" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Rain</td> <td width="22%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/16.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/17.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/18.gif"></td> </tr> <tr> <td width="32%" height="25" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Rain shower</td> <td width="22%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/15.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/14.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/14.gif"></td> </tr> <tr> <td width="32%" height="25" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Snow</td> <td width="22%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/21.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/22.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/23.gif"></td> </tr> <tr> <td width="32%" height="25" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Snow shower</td> <td width="22%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/19.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/20.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/20.gif"></td> </tr> <tr> <td width="32%" height="25" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Sleet</td> <td width="22%" align="center" height="25"><font face="Arial,Helvetica" size="2"><img border="0" src="//www.woweather.com/daten/expertgifs/24.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/25.gif"></td> <td width="23%" align="center" height="25" bgcolor="#FFFFFF"><img border="0" src="//www.woweather.com/daten/expertgifs/25.gif"></td> </tr> <tr> <td width="32%" height="25" bgcolor="#EEEEEE"><font face="Arial,Helvetica" size="2">Freezing rain</td> <td width="22%" align="center" height="25"><img border="0" src="//www.woweather.com/daten/expertgifs/13.gif"></td> <td width="23%" align="center" height="25"><img border="0" src="//www.woweather.com/daten/expertgifs/12.gif"></td> <td width="23%" align="center" height="25"><img border="0" src="//www.woweather.com/daten/expertgifs/12.gif"></td> </tr> <tr> <td width="32%" align="center" height="25" bgcolor="#FFFFFF"></td> <td width="17%" align="center" height="25" bgcolor="#FFFFFF"></td> <td width="17%" align="center" height="25" bgcolor="#FFFFFF"></td> <td width="17%" align="center" height="25" bgcolor="#FFFFFF"></td> <td width="17%" align="center" height="25" bgcolor="#FFFFFF"></td> </tr> <tr> <td width="32%" height="18" bgcolor="#EEEEEE">Cloud Cover</td> <td width="17%" align="center" height="18" bgcolor="#EEEEEE">0-2</td> <td width="17%" align="center" height="18" bgcolor="#EEEEEE">3-4</td> <td width="17%" align="center" height="18" bgcolor="#EEEEEE">5-7</td> <td width="17%" align="center" height="18" bgcolor="#EEEEEE">8</td> </tr> <tr> <td width="32%" height="25" bgcolor="#EEEEEE">(eights)</td> <td width="17%" align="center" height="25"><img border="0" src="//www.woweather.com/daten/expertgifs/few.gif"></td> <td width="17%" align="center" height="25"><img border="0" src="//www.woweather.com/daten/expertgifs/sct.gif"></td> <td width="17%" align="center" height="25"><img border="0" src="//www.woweather.com/daten/expertgifs/bkn.gif"></td> <td width="17%" align="center" height="25"><img border="0" src="//www.woweather.com/daten/expertgifs/ovc.gif"></td> </tr> </table> </div> </div> <div class="eI0"> <div class="eI1">GDAS</div> <div class="eI2">The Global Data Assimilation System (GDAS) is the system used by the National Center for Environmental Prediction (NCEP) Global Forecast System (GFS) model to place observations into a gridded model space for the purpose of starting, or initializing, weather forecasts with observed data. GDAS adds the following types of observations to a gridded, 3-D, model space: surface observations, balloon data, wind profiler data, aircraft reports, buoy observations, radar observations, and satellite observations. </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>