Gray skies covered the Rio Grande Valley on Monday, but the haze isn't from rain. It's smoke from agricultural burns in southern Mexico and Central America.

Warmer air is trapping the smoke. Wind is pushing it north into the Valley.

The air quality index hit a high of 107, according to AirNow. That's considered unhealthy for sensitive groups.

"The air is a little bit different," Weslaco resident Kranthz Esparza said.

Esparza's family is feeling the effects.

"They get headaches, they get runny noses," Esparza said.

Hidalgo County Health Authority Dr. Ivan Melendez said the public should keep an eye on the air quality levels.

"Is this at a dangerous level? Absolutely not. Is it something we need to watch? Of course we do," Melendez said.

People with severe allergies, asthma or who rely on oxygen should stay indoors.

"Limit your activities outdoors; this is not a good time to go jogging or walking outside," Melendez said.

Melendez said people should see a doctor if they develop a fever, have difficulty breathing, or experience wheezing that won't go away.

"Their usual symptomatic treatments, whether they be breathing treatments, antihistamines, or decongestants, are not working – certainly it's time to schedule a visit with your doctor," Melendez said.

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