There could be flooding today near the A414 road between Hatfield and London Colney - following heavy rainfall yesterday.
The Met Office has issued a yellow warning for Tuesday as Storm Brendan approaches.
The Environment Agency has issued a flood warning for areas in and around Hatfield, London Colney and North Mymms - which could affect A414 journeys.
A yellow weather warning is in place for Hertfordshire this morning.
They say only three things are certain in life: death, taxes, and the famous fleet of Hertfordshire County Council gritters.
Heavy rain is expected to hit large parts of the UK this afternoon, including across Hertfordshire.
Gritters in Hertfordshire will not be sent out until it gets colder this winter - after councillors lowered the trigger temperature to 0.5°C.
The Met Office have issued a yellow weather warning for today.
The Met Office has issued a yellow weather warning for the East of England tomorrow with thunderstorms expected across the region.