HOUSTON -- Drivers are advised to use caution early Wednesday as dense fog has descended on the Houston area.

As of 4:30 a.m. crews were still working to clear an earlier crash that has several lanes of I-45 North northbound blocked at Richey. The freeway has since fully reopened, however.

Police say a Jeep slammed into the back of a street sweeper truck in the foggy conditions.

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The driver of the Jeep was not hurt. The driver of the street sweeper was taken to the hospital to get checked out.

KHOU 11 Meteorologist Chita Craft says we are under a dense fog advisory until 10 a.m. with most parts of town getting less than a quarter mile of visibility.

Remember: Do not use your high beam headlines in foggy conditions as that will only make visibility worse.