Two lanes are closed on the motorway between junction nine for Tewkesbury and junction eight for the M50 after the accident.
Highways England said delays are expected until around 8.30am.
A tree fell on a train track in Ickenham, Greater London, and caused severe delays on the Metropolitan Line.
Anyone travelling between Uxbridge and Harrow on the Hill is advised to check their routes before setting off.
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Both the Severn Bridge and the QE Bridge have also been closed due to high winds from the storm.
Rail services throughout the country are also expected to be hit.
Gatwick Express, Southern Rail and Thameslink services are all experiencing delays.
A large tree fell on the clockwise carriageway between junctions 17 and 18 on the M25, temporarily halting all traffic.
The A20 from Kent to London has also been blocked in both directions due to fallen debris.
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Vince Crane, of the AA, advised drivers to take extra care in the worsening conditions.
He said: "Road conditions can quickly deteriorate during very heavy rainfall, with drains becoming swamped or blocked and standing water causing surface spray, reduced visibility and potentially leading to flooding.
"Drivers will need to take extra care and expect delays, even on motorways.
"Strong or sudden gusts of wind are more likely on open stretches of road, when passing bridges or gaps in hedges, or when overtaking high-sided vehicles."