Pay attention to weather reports even if it is calm and sunny. Stay within your comfort zone and ability.
Consider what gear you are bringing along and what type of kayak or SUP you are paddling, inflatables and SUP's are extremely difficult to manage in wind and rain. It is also crucial to wear a personal flotation device (PFD) at all times. When kayaking in windy conditions, it is advisable to paddle close to the shore or along sheltered areas to minimize the risk of capsizing. If your paddling on a long journey, plan in advance some take out points in case you need to end the journey sooner. Having a dry bag with a waterproof and spare clothes can mean the difference to having a good journey or a miserable one.
Relying on a phone for where you are on the map or other information is not always the best plan as signal can be affected in bad weather. If the weather or wind get too bad whilst you are out, consider getting to land and seeking some shelter till it passes, or you can make alternative plans. This is particularly important if you are paddling in less protected waters. Consider where the wind will blow from and too. Paddle where the wind is not likely to be a problem. If the waves are hitting a beach or wetlands or vegetation paddle near shore. If the waves are bouncing off rocks paddle far enough that the rebound wave does not hit the boat. Always let somebody on land know you paddle plans and arrange a callback time so they know you are safe.
Overall paddling is statistically safe but when paddlers do get in trouble it is usually in many cases preventable or down to lack of planning. Last of all please check before and during your trip the wether reports as conditions can change very quickly. By following these tips and remaining cautious, you can have a fulfilling kayaking experience while staying prepared for any wind and weather challenges that may arise.