It didn't rain in San Francisco in January. At all

For the first time since weather records began in 1850, San Francisco received exactly zero inches of rain in January, during what is meant to be its peak wet season.

Data collected by the US National Weather Service shows that on average the city receives around 4.5in of precipitation in the first month of the year.

But despite experiencing a wet December, during which the city saw 16 days of rain totalling 10.66in, 6in above the December average, January saw no measureable precipitation being recorded at all.

According to the US Drought Monitor, a majority of the state of California is in a state of 'extreme' drought with 40 per cent experiencing 'exceptional' drought.

In addition to the drought it is already experiencing, California's mountain snow is also well below average levels.

Mountain snows provide nearly a third of California's water, so a drop in mountain snow could also exacerbate existing drought levels.

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