Julie and I tend to stay out 8 hours or more. Sure, we'll head in early, should we catch all we want. Our shortest day was summer before last when we had 2 WSBs each, all 4 over 40lbs, we were done fishing by 7:00AM, after launching about 4:30AM. Some go for only a few hours, to each their own.
This time of year is more unpredicatable than summer, but if you don't mind cold mornings, and occasionally getting wet on launch, you can catch good day time weather, with whales to watch, to boot.
About what the weather, tides and wind, we use these 3 websites, which help greatly in our decisions, and are generally fairly accurate:
For weather today and about 5 days in the future (updated every 10-12 hours), click on the map, where you plan on going, do it again, and again, to pinpoint the exact location you're fishing:
http://www.wrh.noaa.gov/sgx/
For
current wind (updated every 10-30 minutes):
http://w9if.net/cgi-bin/torreywx/wx.pl
For
tides (not predications, but accurate calculations):
http://tides.mobilegeographics.com/locations/3220.html
We name these on our "Favorites" pull down menu as Weather, Wind and Tides, all you need to know. The tides are important when leaving your kayak at the launch to park or retrieve your vehicle. Too close to waters edge, a rapidly rising tide coulld wash your kayak off of the beach, especially with no one watching after it.