If you’re headed to the beach, you might check a weather forecast to make sure you’re in for a sunny day.

But did you ever consider checking for algae before you grab your swimsuit and chair?

The National Oceanic and Atmospheric Administration’s National Centers for Coastal Ocean Science recently made real-time forecasts of harmful algal blooms along the coast of the Gulf of Mexico and Florida available to the public. They provide hourly observations of algal bloom conditions at beaches in both Florida and Texas.

Algae are tiny, but they can create big health problems. The minuscule organisms flourish in places where fresh and ocean water mix, although they can bloom, or explode in population, in any body of water. When they do bloom, harmful algae can discolor the water — think highly visible “red tides” or the bright, green-colored scum that can form on top of ponds and other bodies of water.

But out-of-control algae can do more than discolor water. They can contaminate shellfish, deplete the amount of oxygen in water, sicken pets and irritate people’s skins, lungs and even nervous systems. Some harmful algal blooms can even lead to paralysis, memory loss or death.

NOAA scientists have long worked with public health officials to track harmful algal blooms and try to predict where they’re likely to erupt and what their effects might be. Advances in satellites and buoy monitoring now enable better monitoring, and the forecasts for both Florida and Texas beaches now include hourly observations for individual beaches.

NOAA’s harmful algal bloom website gives an estimate of the risk for respiratory irritation over the next 30 hours and shows the likelihood of whether a bloom might intensify or change, along with real-time satellite imagery and other resources.

Human-caused climate change is expected to make harmful algae bloom more often, thanks in part to sea level rise, extreme weather and droughts that add more salt to freshwater. NOAA already forecasts the blooms in the Gulf of Mexico and Florida, the Gulf of Maine and Lake Erie, and will soon add forecasts for beaches in California and the Pacific Northwest.

Curious about where algae is blooming right now? Visit bit.ly/harmfulalgalbloom to find out.