Severe flooding has rendered the A31 impassable in both directions between Alton and Farnham, with many motorists reportedly stranded.
Some stretches are so flooded the water has reportedly spread over the central reservation, with one motorist claiming the situation is the worst they have "ever seen".
Reports suggest the southbound lanes are just passable with very cautious driving, while the northbound lanes are a "complete no-go".
Motorists stranded in the flood water have painted a chaotic scene, with some expressing surprise the road was still open.
At least one accident has been reported between Holybourne and Froyle. The police have been called, and approached for an update by the Herald.
There are widespread reports of flooding across the area, with the A325 also said to be near-impassable by Country Market in Bordon and at Rowledge.
The B3006 Selborne Road has also been described as "completely impassable" and heavy flooding is also reported on the A339 Alton to Basingstoke road.
In Farnham, Lower Weybourne Lane is flooded under the railway bridge, and Greenfield Road in Wrecclesham is also under water.