January/February: These months a usually cold, but have some warmer days that are bearable. If booking in advance, I recommend two dates so that, in case the first scheduled day has inclement weather, we have a back-up date. Most trees are missing leaves and the grass is a light brown. If you want a green background, mountain cedar stays green year-round and you can find patches of green winter grass. The tall brown grass can have some wonder backlight effects during the golden hours.
I try not to schedule sessions in the morning hours, as it can be cold and sometimes very damp. We always have the opportunity to have a rare snowfall that is heavy enough for photos, but the key word is 'rare.' Therefore, North Texas is not equipped to clear the roads to make them safe enough to travel to your destination.
March: The beginning of the month is similar to Jan/Feb and we can still have some snowfall or ice. Mid-month, we can have more winter grass and some of the bulb flowers; tulips/ daffodils start to bloom. Trees start showing a small amount of leaf growth near the end of the month. It is still cool in the morning near the end of the month, but bearable.
April: This is one of my favorite months for sessions. Usually the first part of the month, leaves are starting to emerge on most trees and they produce a very bright, light green hue. By mid-month, most species of trees are full of leaves.
Although rain and storms can be a factor, the temperatures make it ideal for being outdoors and time of day. During mid to late April, many of the more popular wildflowers - such as bluebonnets and Indian paintbrushes - start to bloom. The only setback is that it is hard to find these in a location safe to bring a horse.
May: Much of May is like late April - very green and the weather is nice, until near the end of May when temperatures start to rise. Many of the April flowers are gone, but now several more types of wildflowers start to bloom. We can still have a heavy rain or storm. With all the spring rain, stock tanks and creeks are a little fuller and can be used for some great backdrops. The calm morning helps make some beautiful reflections in the water.
June: With temperatures rising, the landscape starts to change. Trees are still green, but the native grasses have gotten taller and start to turn yellow/brown. I love photos during the golden hours during June. The long day makes it easy for those who work during the week, to schedule a session on a weekday.
July/August: One word - HOT! There is a big difference in the color of the trees and natural grasses. I try to start sessions as early as possible or as late as possible to avoid the heat.
September: Early in the month, it is still hot, but it does cool some later in the month. Unlike many parts of the country that see some true fall weather, we still a in the full of swing summer. Mornings in the later part of the month are somewhat cooler and very pleasant.
October: Although many parts of the country are seeing fall colors, North Texas is still green and if we get enough rainfall, it can sometimes be a little spring-like and some natural grasses will have a some new growth. October is another one of my favorite months. Beautiful weather with crisp mornings make it a very popular month for photos. Some of the Sumac trees start to turn red either late in the month, or early November.
November: Many think that we have leaf change in October, but it actually happens in November in North Texas. Although the leaf change is rather dull in Texas, I have noticed it is actually better following a very dry year. The heaviest leaf change is from mid-November to late November. Thanksgiving day always seems to have good color. Of course there is no guarantee of when or if we will have color change. Weather can be unpredictable, with the first frost of the year usually occurring mid-month, so mornings can be cold.
December: Early in the month, leaves are starting to fall, which can make for some pretty background effects. We start to have more consistent cold weather, and some winter storms are always a possibility. Although we may have some very cold days, there are still plenty of days that are very pleasant and sessions are still possible.
Update: 2015 proved me wrong in many ways. With record breaking rainfall and an unusually warm December, proofed by drought theory wrong. The fall colors were the best I have ever seen and did not start until after Thanksgiving and went into early to mid December.
Although I didn't mention wind as a factor, we do have wind much of the year except during the hot summer months when we would actually like a breeze to help cool off.