This year and last have developed some unusual weather patterns, but in terms of wind you'd have to look at the frequency and intensity of storms over the past 50 years.
The Met Office maintains stats going back for more than a hundred years and digging out the detail is notoriously time consuming, but some things are fairly clear: the weather and the planet are warming, and that warming brings with it an increase in intense events - such as storms. Having said that, the UK weather remains remarkably consistent, mainly because of two factors: the fact we're an island, so the large amounts of water around us tend to leaven out weather anomalies, and the jet stream hasn't really done a significant shift since records began.
Llandudno has always been notable for having one of the lowest rainfall figures in the UK and one of the highest average wind speeds. The winds always tend to come from the SW - W, which is why the cable car was built so it's shielded from the worst, other than at the final approach to the summit.
Comparisons with when you were young are not easy to make, since a lot of factors would influence your recollections. Geographical location is one major aspect, while young people tend to sleep more deeply and consistently than those of the older, more mature variety. Also, rattling slates aren't a good indicator since you might have less well-affixed slates here than you did when you lived elsewhere. Don't want to worry you unnecessarily, but one reason slates might rattle in Llandudno is down to the corrosive effects of the salt in the air. Apparently, nails don't last as long here...
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