Storm Lorenzo: October 3/4 2019 **Technical Discussion Only**

M.T. Cranium wrote: »

So here's a question about the warning system, if they (or we here at Boards) went to a more fine-tuned system breaking down counties into parts, which counties would you consider most in need of regions and what would you propose for them?

As a first draft of this, I would say that these counties do not need further dividing into regions for warnings:

Sligo, Leitrim, Roscommon, Cavan, Monaghan, Louth, Meath, Longford, Westmeath, Offaly, Dublin, Kildare, Laois, Carlow, Kilkenny, Wexford, Waterford.

For the rest, this would be the proposed sub-county grid for warnings:

Kerry north, Kerry south, Cork north, Cork south, Limerick west, Limerick east, Tipps north and south, Clare northwest, southeast, Galway west, central, east, Mayo northwest, southeast, Donegal south, Donegal north, Wicklow east, Wicklow west.

Then if this grid were in use, a warning that did not break down the county would apply to all parts.

Alternatively, you could make the system totally map-dependent, and just issue warnings for "all of" and "parts of" counties with a map published to show what zones were in what categories.

For this past storm, I would imagine the orange warnings might have been restricted to some parts of at least Clare, Galway, Cork and Mayo, with yellow for the more inland portions so the map would have looked more yellow and less orange basically. If no regions were being used and just the zones on a map, then probably the orange zone would have been most of the west coast within 20-30 miles of the ocean.

Also it might be helpful for maps to have two styles of shading for wind and rainfall, same colours but say solid orange for the wind warning and hatched orange for the rainfall (which in this case in hindsight may not have overlapped and in fact there was probably a zone of yellow wind and rain verifying in the space (north Mayo-Sligo) between them.

Can see that Sligo, Leitrim and Roscommon often have north-south differences that might add them to my list of possible divisions. Give this some input and I will get a base map created (if the prevailing opinion favours breaking down counties and not just the map based system) for use here, and we can help fine-tune these warnings.

Is this breakdown fine enough to make the system potentially more responsive, or would you need even more of a subdivision?