What does the red mean?

[Sleep Deprivation Chamber]

I am not a pilot, but I found this chart and am wondering how to decipher it. In particular, what do the numbers in the red mean?

<A HREF="http://www.awc-kc.noaa.gov/awc/intl_sigmets/ipsigmet.gif" TARGET="_blank">http://www.awc-kc.noaa.gov/awc/intl_sigmets/ipsigmet.gif</A>

Thanks,

Charles Pribyl
Kanazawa, Japan
(hence the interest)

[johnv]

Turbulence from 24000ft to 34000ft.