The National Weather Service is increasingly confident there will be severe weather in Alabama on Wednesday.

In fact, the weather service office in Birmingham said a "severe weather outbreak is expected" beginning Wednesday afternoon lasting possibly into Wednesday night. A risk of severe weather at varying levels will cover the entire state.

A portion of northwest Alabama will have a heightened -- or enhanced -- risk of storms on Wednesday. All of Alabama will be under a slight risk of severe weather as well, according to the Storm Prediction Center.

According to the Storm Prediction Center, an enhanced risk means that numerous severe storms will be possible, including a few tornadoes, golf-ball-size hail and damaging wind gusts that could be up to 70 mph.

The weather service in Birmingham said strong long-track tornadoes are possible in the northwest portion of its forecast area -- roughly northwest of Interstate 59 -- and upgraded the risk for that portion of the state to "significant."

The prime window for storm development was from 3 p.m. until around midnight, the weather service said. However, strong storms would be possible any time.

The Birmingham office said that the thinking now was that the severe weather threat, including tornadoes, could continue in its forecast area through 6 a.m. Thursday.

The National Weather Service in Huntsville said that the primary threats on Wednesday in north Alabama will be damaging winds and large hail. Tornadoes, while possible, will be a secondary risk.

Farther to the south and east, there will be a slight risk of severe storms. A slight risk means scattered severe storms will be possible with one or two tornadoes, quarter-size hail and strong wind gusts up to 60 mph.

Wednesday has the greatest potential for the worst weather, but there will be marginal risks of severe storms today and again on Thursday for portions of the state, according to the Storm Prediction Center.

The timing and the details may change, but as of Tuesday morning the setup could be this, according to forecasters: A plume of tropical moisture is expected to be streaming across much of Alabama on Wednesday. Another in a series of troughs of low pressure will also move into the area, and there will be wind shear and instability to work with as well.

The thing to watch for those farther inland will be storms along the Gulf Coast. A mass of storms there could limit the inflow of warm, moist air and limit the severe risk farther north. The weather service said Tuesday morning that models suggested that storms will be present along the coast on Wednesday but could shift eastward into Georgia early in the day.

There is no set window for storm development, but as of Tuesday morning it appeared that Wednesday afternoon and evening would be the best times for severe storms to develop, according to the weather service.

The bad weather will also be accompanied by warm temperatures -- and some spots could set high temperature records this week.