Significant wx-charts new symbol

[HF-Tuner]

Hello together,

I found a new symbol on the significant wx-charts of Bracknell. Since a few days there are two numbers separated by a dash below the flight level of a jetstream combined with a CAT.

The FL of the jet is for example 310 and it says below -60/+90. One could think that this are the upper and lower border of the CAT, but this doesn´t match the limits of the CAT stated in the box in the upper left corner of the chart.

Any ideas or have I missed something everybody knows for ages?

[Le-Slat Disagree]

Hi HF-Tuner

I believe, but will stand corrected as I'm not 100%, but the -60/+90 refers to the hundreds of feet i.e. 6000 & 9000 where the wind speed is greater than (i think) 80 knots.

I too have only just noticed them in the last couple of months and would also be interested to know if my theory is anywhere near the mark.

Cheers

Le-Slat

[BOAC]

look here (http://www.pprune.org/forums/showthread.php?s=&threadid=159921&highlight=significant)