As shown in
Solar Panel Technology Comparisons it is NOT true that evacuated tubes are the best for pool heating even in winter. That technology is best for much larger temperature differences so for domestic hot water heating in the winter. The best technology for heating including the winter months is glazed panels. These used to be about three times as expensive as unglazed black plastic panels but these days it's more like twice as expensive (and evacuated tubes are twice the price of glazed panels).
Even with glazed panels you will likely need to supplement heating the pool in winter with gas unless you thoroughly insulate your pool. That means a very insulating cover, but also insulated piping and even insulation around the gunite shell. So unless you had the pool built with a design for having minimal heat loss, you simply aren't going to have enough sunlight in the winter to keep the pool heated unless you have a VERY large surface area of panels. Technically, glazed panels absorb no more heat than unglazed (they actually absorb a little less) but where they are better is that they do not re-radiate their absorbed heat back to the air very much. So with colder air even with wind the glazed panels continue to operate. The problem is that in the winter there is far less sunlight.
What is relevant in terms of heating is knowing the average day/night temperature. In July and August in Riverside, that's about 80ºF so even a clear bubble-type solar cover alone would easily heat the pool by itself. In June and September with the average day/night temperature being 74ºF and 77ºF respectively, a cover alone should still be OK since it can usually increase water temps by 10ºF, but you shouldn't expect more than 15ºF from a cover alone. That's where solar heating kicks in another 10-15ºF for a net 25-30ºF rise or more (in summer) depending on your panel surface area. The problem will come in the winter where December through February average roughly 56ºF so to get to 85ºF you need a 30ºF increase.
Riverside, CA is at about 34ºN latitude so at the transition of spring to summer (late June) the sun is 34-23.5 = 10.5º from vertical so the sun's peak 1000 Watts per square meter is only cut down to 1000*cos(10.5º) = 983. However, at the transition of fall to winter (late December) the sun is 34+23.5 = 57.5º from vertical so only 1000*cos(57.5º) = 537 Watts per square meter. That also assumes you have a sunny day with no clouds or even haze.
So basically to get that 30ºF increase during the winter, you may not only need glazed panels, but an area of them that is at least 150% of your pool's surface area. While having panels with 80% of your pool's surface area would be fine for extending the season through spring and fall, getting through winter would need more area. Even then, this assumes no clouds or haze. With cloudy days the sun's output may be only one-third or less of it's peak so for such days you'd need three times that 150% of panel area to heat with the panels on those days. So you can see how this quickly becomes impractical. Instead you would likely use gas heat during the winter. Whatever panels you have may help a bit but the bulk of your heating would come from gas.