Its probably because the postcode falls in the area the warning covers geography wise but in reality if you read the details of the actual warning its never going to bother us. Its all further north than us really and above 200m :-
YELLOW WARNING of SNOW for southern and central Scotland and northern England.
Issued at 0310 on Thu 14 Jan 2016
Valid from 0315 on Thu 14 Jan 2016 to 1500 on Thu 14
Further outbreaks of rain, sleet and snow are expected during Thursday morning, clearing from the north and west through the day. The heaviest snow is still expected to affect parts of southeast Scotland (for which a separate Amber warning is in force) and upland areas of northern England, including cross-Pennine routes, where 3 to 6 cm may fall in a number of areas, with possibly as much as 10 cm locally, mainly above elevations of 200 metres. Ice will be an additional hazard as the sleet and snow clears from southeast Scotland.
Please be aware of the risk of disruption to travel, and take appropriate precautions before undertaking journeys. It will also be worth keeping fully up to date with the latest forecasts - details of amounts and areas affected may well change.
This is an update to extend the warning area to include the North York Moors, whilst at the same time trimming the northwestern limit over Scotland - now covered by a separate ice warning - and to cease the warning by mid afternoon.
I'd be very confident you will get to Calow and back and not see a hint of any white stuff falling and definitely not enough to cause any potential issues bar some road users deciding to drive at 10mph cos there is some white stuff falling yet the roads are dryer than if it'd been raining!!
