Why temps will rise nearly 20° by Tuesday

AUSTIN (KXAN) -- A potentially historic heatwave is becoming more likely in the coming few days. All-time May record high temperatures are forecast to be broken for several cities in Central Texas.

LATEST FORECAST: From the First Warning Weather team

Widespread Heat Advisories and Extreme Heat Warnings are expected to be issued as early as Tuesday.

Refresher: Heat Alert Criteria

BLOG: Here’s why ‘Excessive Heat Warnings’ are going away

Heat Advisories are issued when air temperatures are forecast to reach 103º or higher, or when heat index values are expected to reach 108º or higher.

Extreme Heat Warnings are issued when air temperatures are forecast to reach 105º or higher, or when heat index values are expected to reach 113º or higher.

What will cause the rapid change of temperature in a short amount of time?

A strong high pressure ridge will remain stationary over Texas, keeping temperatures 10-20° warmer than normal. A high-pressure ridge is characterized by sinking air, which limits cloud cover and rain development.

Think about it like this - the ridge "traps" warm temperatures for an extended period of time. Until the ridge weakens or moves, temperatures remain hot.

Computer models continue to show efficient surface heating driven by less available moisture, warmer air mixing down aloft, and minimal cloud cover. All of these components contribute to rising high temperatures.

When will temperatures begin to cool off?

The high-pressure ridge will keep Central Texas warmer than normal through the end of next weekend. As the ridge will slide east, a dip in the jet stream will bring cooler temperatures and a chance for much-needed rain.

Stay weather aware and remember to practice heat safety wherever you are. Stay hydrated and take frequent breaks, check up on the sick and elderly (especially those without AC), and never leave children or pets unattended.