WW2010
University of Illinois

WW2010
 
  welcome
 
> online guides
 
  archives
 
  educational cd-rom
 
  current weather
 
  about ww2010
 
  index

Online Guides
 
  introduction
 
  meteorology
 
  remote sensing
 
> reading maps
 
  projects, activities

Reading Maps
 
  introduction
 
  utc conversions
 
  temp conversions
 
  surface obs
 
  surafce maps
 
  upper air obs
 
  upper air maps
 
> forecast maps

Forecast Maps
 
  300 hghts, winds
 
  300 hghts, temps
 
  500 hghts, vorticity
 
  500 hghts, temps
 
  700 hghts, humidity
 
  700 vvel, precip
 
  850 hghts, humidity
 
  850 hghts, temps
 
  1000 convrg & temp
 
> sfc precip, prs, thk

User Interface
 
  graphics
> text

NOTE: We've guessed that you're not using a client that supports colored tables and have tried to compensate. Low graphics mode looks much better on clients that do... we recommend switching to Netscape 3.0 or Microsoft Internet Explorer.
.
Surface Precipitation, MSL-Pressure & 1000-500 mb Thickness
model mode

[Image: surface forecast panel of quantitative preicip, msl-pressure and 1000-500 mb thicknesses (55K)]

This panel shows the forecasted fields for mean sea-level pressure, 1000-500 mb thickness and surface quantitative precipitation.

Mean sea level pressure is simply the pressure at mean sea level and is represented by the solid blue contours. The mean sea level pressure field is given in millibars with an interval of 4 mb between pressure contours, also called isobars. The locations of high and low pressure systems can be determined from the sea level pressure field. Winds tend to blow clockwise around areas of high pressure and counterclockwise around areas of low pressure. The closer together the isobars, the stronger the winds.

1000-500 mb thickness indicates the distance in meters between the 1000 mb and 500 mb pressure surfaces and is represented by the dashed yellow contours. The thickness field is given in meters with an interval of 60 meters between thickness contours. Thickness is directly related to temperature; as thickness decreases, so does temperature. Precipitation type can also be estimated from the thickness field with the 5400 meter thickness serving as the rain/snow line. Snow falls where thicknesses are below 5400 and rain occurs where they are greater.

Quantitative precipitation is represented by the color filled regions and the associated values are indicated by the color code located in the lower left corner of the forecast panel. Precipitation totals are given in inches with totals of less than 0.51 inches shaded in purple with heavier totals shaded in green, yellow and red. Quantitative precipitation is the estimation of the liquid equivalent precipitation that would occur during the 12 hour period. For example, quantitative precipitation fields for 0000Z 24 March 1996 represent the amount of precipitation that is predicted to occur from 1200Z 23 March to 0000Z 24 March 1996.

In this particular image, the important feature is the surface cyclone located in the southeast corner of South Dakota. As much as 1.5 to 2 inches of liquid equivalent precipitation is expected over the 12 hour period ending at 0000Z October 27 1996. Most of this precipitation should fall as rain (or freezing rain) since the 1000-500mb thickness is above 5400m in that region.



1000 convrg & temp
Terms for using data resources. CD-ROM available.
Credits and Acknowledgments for WW2010.
Department of Atmospheric Sciences (DAS) at
the University of Illinois at Urbana-Champaign.

Projects, Activities