Pronóstico según el modelo GFS expedido por el Centro Nac. de Predicción Ambiental EEUU COLA
(Center for Ocean-Land-Atmosphere Studies).
Fuente: http://wxmaps.org
volver
02-10-10 al  07-10-10
Paneles de corriente jet e isotacas a 200 mb
 

 


EXPLICACIÓN DE LOS MAPAS COLA
(Center for Ocean-Land-Atmosphere Studies)
Fuente: http://wxmaps.org

Mostramos dos páginas:
Panel "d":  De temperatura, humedad y viento a 850 mb, un muy buen indicador de la intensidad del viento a la altura de los filos de montaña. (850 mb = 1.540 m)
Panel "e": de vientos a 200 mb, es decir dirección e intensidad del jet stream. Este dato es esencial para conocer el gradiente de las velocidades ya que nos informa dirección e intensidad de los vientos a gran altura (200 mb = 12.000 m).
Mas información ver:


Guide to the Forecasts and Analyses

We describe and display the results from the forecast models of the U.S. National Center for Environmental Prediction (NCEP), but similar procedures and products are common to forecasting centers in other countries. This guide is not meant to be a thorough and complete description, but to give an overview of the forecasts and their presentation.

There are three views for the forecasts and analyses - one centered over North America (for the regional and global models), a view of the entire Northern Hemisphere centered over the Atlantic Ocean (for the global model only), and a similar vie for the Southern Hemisphere. For each model there is an analysis, and then a number of forecasts at regular intervals. The regional model forecasts are only displayed out to 48 hours, but the forecasts from global models continue longer. We now produce six different panels for each period, as opposed to the four we were producing previously, and which NCEP continues to produce. The contents and meaning of the six panels is described below in detail.

The analyses represent the initial state for the integration of the various forecast models. The analyses are produced from observations at weather stations around the world, as well as ship and buoy reports at sea, reports from aircraft, radiosonde balloons, and even satellite data. These data are merged after quality control procedures have been applied. Even with all of the data sources, there are still tremendous gaps in coverage over remote areas. An optimal interpolation (OI) procedure is performed using the previous model forecasts to fill these gaps and create a complete picture of the state of the atmosphere at the forecast time T=0. The various models are then integrated forward in time to produce the forecasts which are displayed here.

At the bottom of each map is a bar telling the date and time for which the analysis or forecast is valid, the number of hours after the analysis for which the forecast is valid, the fields displayed, and their units. The six types of maps are described below.

Panel d

850mb (1.543 m) Temperature, Humidity and Winds

  • Colored contours indicate the air temperature at the 850 millibar (1.543 m) level, in degrees Celsius. The 0�C contour is highlighted, as this is also often used as a divider between rain and snow.

  • The green shading indicates the relative humidity percentage at the 850  millibar (1.543 m)  level. High values indicate the availability of moisture. When large rates of ascent (in panel 3) are located with high moisture availability, heavy rainfall will likely occur.

  • The barbs indicate the direction and speed of the wind, in meters per second. Each full barb indicates 10 m/s, and each half barb 5 m/s. The direction of the wind is parallel to the shaft with the barbs pointing into the wind.

    • Advection of moisture by the wind can be inferred by noticing the direction and rate at which moist areas appear to be blown. Similarly, temperature advection can be inferred by noticing whether the wind is blowing cold air toward a warm region, or warm air toward a cold region.

Panel e

200mb Winds

  • Purple shading indicates the speed of the winds at the 200 millibar (12.018 m) level, in meters per second. This altitude is near the level of the core of the jet stream. So the tracks of the jet streams can be seen very clearly.

  • The streamlines indicate the direction of flow of the wind, which is generally from west to east throughout most of the subtropics, mid- and high-latitudes.

  • The color of the streamlines indicates a relative measure of divergence of the flow in the upper troposphere. Orange and red indicates strong divergence at upper levels, usually associated with strong vertical velocities in the middle troposphere, and severe weather/heavy rainfall.