SNOW falling on top of black ice wreaked havoc on the region's roads today, with numerous accidents reported.

Sub-zero temperatures overnight combined with early morning snow showers to make for nightmare morning rush-hour driving conditions for people in York and across North and East Yorkshire.

On the coast in Scarborough and Whitby and further inland in Ryedale up to 10cm of snowfall made driving conditions particularly treacherous.

The Met Office put out severe weather warnings for snow and ice for all areas and about a dozen schools were closed for the day.

Police advised drivers to only make their journeys if they were absolutely essential and to take all the necessary precautions before setting off.

Numerous accidents occurred on the A1, with two three-car pile-ups occurring in quick succession on the A1 near the Allerton Park turn off at 5.45am and 6.19am. No one is believed to have been seriously injured in either incident. But as a result, the A1 was closed in both directions between Allerton Castle and Boroughbridge, causing lengthy delays.

Police and ambulance crews also attended a further accident involving a single vehicle on the A168 a mile off the A1, but again, no one was seriously injured.

In York, an ambulance was called out after a car came off the road on black ice in Wigginton Road, but no one was injured in the incident.

Inspector Steve Burns, of York Police, said: "We are urging anyone going out to take care and drivers in particular with the weather conditions as bad as they are with the advise being not to make your journey unless it is absolutely necessary.

"If you do have to set off make sure you go prepared - take a shovel, blankets and a flask of hot drink."

A spokeswoman for PA weather centre said: "We are expecting the snow and sleet to turn to rain by midday.

"By then we should have had the worst of the bad weather, but light snow flurries cannot be ruled out later on in the week."

School closed included Slingsby Primary School, Nawton Primary near Helmsley, Langton Primary, near Malton, Thornton-le-dale Primary, Boroughbridge High School, Sinnington Primary School near Malton, Levening Primary School and Welburn Hall Primary School.

Some flights were delayed at Leeds Bradford airport, but the runway was later cleared.

So, were those gritters out?

TAXI drivers said conditions on York's road were horrendous - and criticised the gritting service.

Ernie Dickinson of Local Taxis, said: "Gritters - where are you? I have been out since 5.45am and only seen one, coming out of Foss Islands, with a full load. It seems particularly bad on the northern side of the city, in Haxby, Strensall and Clifton Moor - slushy and slippy."

Simon Mandy, of Ace Taxis, said: "It's absolute chaos. It's terrible. We have drivers stuck in Tadcaster Road - it's chock-a-block. There's been a couple of gritters out, but not enough."

Council officials said their teams had been out round the clock.

They insisted that 180 tonnes of grit had been spread on the city's roads and pavements.

The gritters had been working flat-out throughout the night and morning, and all routes and footpaths had been salted.

A spokesman for City of York Council said: "Our gritting teams were out at 6pm and 8pm last night, 2am and then out again at 6am doing the footpaths and the roads.

"With the snow falling on top of the salt it takes the grit and snow to be churned up by vehicles going over it to have its full effect."

Hold-ups in Acomb were worsened by an accident near the Green, which caused long tailbacks. Police said a Vauxhall Astra skidded on ice, partially blocking the road.

Elsewhere, a car hit a barrier on the A64 near Grimston Bar and two vehicles were involved in a collision at Shipton-by-Beningbrough at 7.40am, but no one was injured.

Difference a year makes

WHAT a difference a year makes - York was basking in sunshine in March last year.

One weather report, published on March 19, 2005, said: "The warm weather which has left much of the UK basking in sunshine is expected to continue this weekend.

"Temperatures have soared in recent days with thermometers rising way above the seasonal average."

That sunshine came a week after York's last big freeze which struck the city in February 2005. Then heavy snow caught the gritters by surprise and minor crashes and prangs were the order of the day.

Forecasters said the weather for the next five days would be as follows.

Tuesday: snow, 1C (day time) 1C (night time)

Wednesday: sunny spells, 5C (0C).

Thursday: sleet and snow 4C (-1C).

Friday: sunshine and snow flurries 3C (2C).

Saturday: showers 4C (3C).

Updated: 12:29 Tuesday, March 14, 2006