University of Illinois

> online guides
  educational cd-rom
  current weather
  about ww2010

Online Guides
  remote sensing
> reading maps
  projects, activities

Reading Maps
  utc conversions
  temp conversions
  surface obs
> surface maps
  upper air obs

Surafce Maps
  obs, isobars, radar
  obs, isobars, ir sat
  temp contours
  temperatures, winds
  dew point reports
  dew points, winds
  24 hour totals
> analysis pairs

Analysis Pairs
  press & temp
  dew point
  mixing ratio
  moist. convergence
  temp. advection
> dew point advect
  3hr dew pt & wind
  3hr temp & wind
  3hr press & wind

User Interface
> 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 Dew Point Temperature Advection
surface analysis pairs

Example Surface Dew point Temperature Advection Image

This is the Surface Dew point Temperature Advection image which is useful for finding areas of positive and negative dew point temperature advection.

Positive advection areas are outlined in solid lines and indicate that the dew point temperature is increasing due to advection. Negative advection areas are outlined in dashed lines, and indicate that the dew point temperature is decreasing due to advection. Both advection areas are contoured in intervals of 10 degrees Fahrenheit per day, so a positive advection outline of 20 indicates that if positive advection was to continue at the present rate for 24 hours, the dew point temperature would warm by 20 degrees Fahrenheit in that region.

At a given temperature, the higher the dew point temperature, the more moisture in the air. By taking dew point temperature advection to be analogous to moisture advection, we can say that when there is positive dew point temperature advection, there is also positive moisture advection.

Severe weather analysts pay close attention to the distribution of low-level moisture. Areas rich in moisture help to destabilize the atmosphere, which in turn support the generation of strong updrafts. If the updrafts occur near areas of positive dew point advection, the potential for significant thunderstorm development increases.

The example image above shows an area of strong negative dew point advection located in Wisconsin, Illinois and into Missouri. This negative dew point advection area is due to a cold front that was passing through those areas at the time of this image. This image clearly shows how much drier the air was behind the cold front than ahead of the cold front.

temp. advection
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.

3hr dew pt & wind