Tuesday, February 12, 2013

Icing prediction using Mixing Ratios

Several of the products that we are looking at for this experiment use mixing ratios to predict regions of icing.  Both the AFWA and SREF ensembles use mixing ratio from each of the members to predict where icing will occur.

The AFWA takes a worst-case approach for explicit prediction of super-cooled liquid.  Shown below is the ensemble maximum SLD mixing ratio (shaded) with the lowest freezing level from the ensemble contoured over the top.  PIREPs for lgt-mod icing or greater have been overlaid on this forecast.'
11 Feb 00Z AFWA forecast of worst case of SLD mixing ratio and lowest freezing level height.  PIREPs are for lgt-mod icing, or greater.
Post-processing on the SREF takes a slightly different approach, looking at cloud water mixing ratio between 0 and -25 C in each member, and produces a probability that icing will occur.  PIREPs of lgt-mod icing or greater are also shown in this loop.
11 Feb 09Z SREF probability of icing.  PIREPs are for lgt-mod icing, or greater.


1 comment:

  1. Several of the products that we are looking at for this experiment use mixing ratios to predict regions weather in lake district of icing. Both the AFWA and SREF ensembles use mixing ratio from each of the members to predict where icing will occur.

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