Impressive, but not unprecedented: Riverbend heat wave to extend until Saturday

ALTON - Temperatures will be breaking three digits over the next few days in Alton.

A representative from the National Weather Service (NWS) in St. Louis said this current heat wave will continue until Saturday evening, when a cold front is set to come through the area bringing with it a 40 percent chance of showers and thunderstorms. Until then, however, meteorologists are warning people to take precautions to stay cool, as projected high temperatures Thursday, Friday and Saturday are predicted to be above 100 degrees. Heat indexes are projected to be between 105-110.

"The difference between heat index and actual temperature is the heat index is what it feels like outside," an NWS meteorologist said Wednesday afternoon. "The body produces sweat, which doesn't evaporate as fast in humid air, making it feel hotter."

Relative humidity is not the only factor giving the air its soupy feeling. The dew point is one of the main contributors. Meteorologists predict the dew point during this ongoing heat wave will be in the low 70s, which will make the evaporation of sweat even harder.

Meteorologists advise people take proactive measures to beat the heat for the next following days including staying hydrated, take plenty of breaks and staying in the air conditioning if possible.

When the cold front comes through the area Saturday night into Sunday, temperatures will drop into the 90s. Sunday's high is predicted to be 94 following the front and possible thunderstorms.

"We could use the rain," a representative from the NWS in St. Louis said. "It's been fairly dry as of late."

This heat wave was described by meteorologists as "impressive," but it is not unprecedented. A longer such heat wave occurred in 2012.

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