High pressure is expected to have an influence when it comes to Alabama’s weather over the next few days.

High pressure usually means drier, calmer conditions and warmer temperatures for Alabama. In fact, some meteorologists use the phrase “big bubble, no trouble” to describe typical weather under the influence of high pressure.

But a different type of high pressure is expected to control Alabama’s weather this weekend and early next week: A “dirty” high.

It’s nothing to be worried about, however.

The National Weather Service actually has a definition in its glossary for a dirty high. A dirty high, according to the weather service, “has a canopy of clouds associated with it. These clouds can form due to orography (or terrain), a saturated PBL (i.e. planetary boundary level) (with low level fog and/or stratus building under a middle level inversion), or lifting mechanisms within the region of high pressure (WAA, moisture advection).”

In other words, “dirty” highs can mean more clouds and more chances for developing showers or storms in their vicinity.

The National weather Service in Huntsville mentioned the influence of a dirty high in its Saturday forecast discussion. Forecasters expect to have plenty of humidity around even with the high’s influence.

The weather service said “High pressure will build across the Southeast this weekend into early next week. This time it will not provide clear skies and dry conditions. This dirty ridge with plenty of moisture in place will keep low to medium (20-50 percent) chances of showers and thunderstorms in each day, mainly during the afternoon to early evening hours.”

The weather service is expecting hot July temperatures and daily chances for rain and storms to linger through the week.

There is a Level 1 out of 5 (or marginal) risk for severe weather on Saturday for the northern part of the state, but organized severe weather isn’t expected for the rest of the week in Alabama (at least so far).