On Thursday, 20 November 2014 13:51:33 UTC, wrote:
Hi

I don't usually take issue with John Hammond, but in the 1.30 PM weather on the BBC today he described the exceptional snowfall around the Great Lakes as frontal (i.e cold and warm air masses coming together), but as far as I can see, although some of that snow was frontal, the majority came about through lake-effect snow (i.e. caused by the water temperature of Lake Erie being around 8°C and the air temperature around -8°C and hence very unstable air combined with a strong westerly flow bringing continuous showers to the lakes coastal communities like Buffalo).

I did expect him to try and briefly explain lake-effect snow, and was very surprised when he churned out the "cold and warm air masses coming together" one.

I'll be interested if he uses the same graphics in the 6.30 PM broadcast.

Bruce.

xmetman: http://wp.me/p3yVic-TL

Did he actually say that? He should be shot. I know the BBC is heavily into dumbing-down but this is not dumbing down but simply wrong and there's no excuse for a forecaster of all people saying it was frontal. Apart from anything elese that would not explain the distribution of snow. It would need an extraordinary temperature contrast to produce that amount of snow, say between Gulf air and Canadian air and there was nothing like that on the GFS surface chart.
How difficult is it for him to say that it was very cold air over relatively warm water? Not very. He could have drawn an analogy with snow showers in north Kent and Essex or even with winter thunderstorms in the Western Isles. Dear me, no, far too difficult. Perhaps, horror of horrors, the forecaster has never heard of lake effect snow. I'm glad I didn't see the broadcast.

Tudor Hughes, Warlingham, Surrey.