University of Illinois

> online guides
  educational cd-rom
  current weather
  about ww2010

Online Guides
> meteorology
  remote sensing
  reading maps
  projects, activities

  air masses, fronts
  clouds, precipitation
  el nino
  forces, winds
  hydrologic cycle
  light, optics
  midlatitude cyclones
> severe storms
  weather forecasting

Severe Storms
  dangers of t-storms
> types of t-storms
  tstorm components

Types of T-storms
  storm spectrum
  single cell storms
  multicell clusters
  multicell lines
> supercells

  on radar
  schematic diagrams
  hp supercells
> lp supercells
  multicell to supercell
  tornadic supercell

LP Supercells
> with tornado

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.
LP Supercell With Tornado
plus rotating cloud bands and vaulted appearance

A westward view of the LP storm model's vertical cross-section shows the LP storm's undersized, rotating Cb and its small, nearly transparent precipitation area. Rotating cloud signatures are commonly visible in this supercell type, and wall clouds are frequently observed.

[Image: vertical cross-section of lp supercell (53K)]

An oddity is that this bare-bones storm type occasionally fosters small funnel clouds that extend from the mid-levels of the Cb rather than from the Cb base! At times weak or even strong tornadoes develop from the vicinity of the wall cloud.

This LP storm did produce tornadoes -- two of them. The storm actually bordered between an LP and a classic supercell as it has a fairly large and intense radar echo (VIP 5), including a pendant. In this westward view, we note that the wall cloud was on the north side of the rain-free base, with spectacular rotating bands arranged much like barber pole stripes around the parent Cb.

[Image: lp supercell with tornado (46K)]
Photograph by: Moller

This view gives us an excellent feel for the scale relationships between the rotating updraft and the tornado that occasionally develops beneath such an updraft. Remember, the radar hook echo is roughly equivalent in scale to the rotating Cb, whereas the tornado itself is much smaller.

[Image: vaulted lp supercell (69K)]
Photograph by: Moller

The same storm is pictured looking northwest, as the tornado was lifting/weakening into a funnel cloud (extreme lower left). The storm has a spectacularly vaulted appearance adjacent to the precipitation area, which was nearly transparent. Scattered raindrops were falling in this precipitation area, along with 5 inch diameter hail! Thus, the lack of an opaque precipitation curtain does not preclude the possibility of very damaging hail.

This storm produced about 5 million dollars in hail damage in Borger, Texas, with one rain gauge that survived the hail fall showing only 1/4 of an inch of liquid rain. The tornado that we have witnessed in these photographs produced several hundred thousand dollars damage to an oil refinery, and several injuries.

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.