A few icy roads caused problems early Tuesday morning in some areas as bitter cold grips the Houston region.

Slick ice was reported about 5:30 a.m. on the frontage road of southbound North Freeway near Crosstimbers, according to Houston TranStar.

Also, Houston police are investigating a four-car chain-reaction that happened about 5:30 a.m. on Gessner near Hempstead, where ice was reported on the roadway. No injuries were reported.

Low temperatures plunged early Tuesday into the teens, especially just north of Houston, according to the National Weather Service. In most spots, forecasters said, the mercury dropped into the mid to lower 20s. A hard freeze warning was issued through 9 a.m. for the region.

The high Tuesday likely will struggle to about 44 degrees. Northeast wind will be about 5 mph, making the temperatures feel even more chilly.

Chronicle photographer Cody Duty contributed to this report.