Temps have already plummeted across Southeast Texas, but the main story will be the chance of significant snow and ice later this week.

HOUSTON – Thousands of runners and walkers take to the streets of Houston this Sunday. Temperatures at the starting line will be in the mid-30s but it will feel like the upper-20s with the wind chill. Temperatures will warm to the lower-40s through the morning under sunny skies. It was actually colder last year.

Southeast Texas' outlook for next week's winter storm continues to worsen, with a growing likelihood of a deep freeze and substantial wintry precipitation, snow and sleet in the Houston area. Space City Weather's Eric Berger published an atypical afternoon report on Friday warning of an "increasingly likely" and drastic mix of hard freeze and snowy conditions expected in Southeast Texas early next week.

An arctic front has already moved across the rest of Texas, bringing freezing temperatures. Snow, sleet or ice could come as early as Monday night.

As a significant winter storm approaches the Houston area, snow, sleet and ice are all becoming certainties as the temperatures decrease and conditions are forecasted to be more frosty than expected.

Temperatures are expected to dip below freezing on Sunday night, according to the National Weather Service. As of Friday, Houston's forecast also called for a likelihood of snow on Monday night and Tuesday morning.