The M4 is closed westbound between junction 14 Hungerford and junction 15 Swindon today (Thursday). National Highways said this was due to a road traffic collision. All three lanes are closed. Thames Valley Police are in attendance. And traffic is being diverted via local roads whilst emergency services work at the scene. National Highways has told motorists to follow the hollow square diversion symbol. Normal traffic conditions are expected between 9.30am and 9.45am today. National Highways said: ”If this incident impacts on your planned route, please allow extra journey time. “Plan ahead, yo…