Calling all experts.

[Graham Easterling]

There's a few runs now that have picked up on this

OK, it's a week off, so everything might change, but I'm curious to know what the models are picking up on to predict an unusually deep depression for mid April. I assume it's related to the blocked pattern we are rather stuck in.

Graham

Penzance

[Freddie]

Hard to tell from a single chart, but deep lows like that are usually the result of a strong jet stream, not blocking.  Looking at the temperature contrast on that chart to the south and south-west of the low, I think there's probably a strong jet there, running WNW->ESE.  But like I say, it's difficult to tell from a single chart.

It's strong jets in April that are unusual in our part of the world - which is likely the cause of the lack of deep April lows.

[Stephen Davenport]

Indeed. Cold air moving out of eastern Canada is setting up a strong temperature gradient and consequently a strong jet over the Atlantic, as the ECMWF shows here in the preceding day.

[Graham Easterling]

Thankyou both.

I appreciate that the strong temperature gradient would likely lead to the development of deep depressions, it's the way that models can forecast the development of a specific deep depression a week off that impresses me. 

Graham

Penzance - Lovely morning after a cold night - min 2.7C.

[Ashley haworth-roberts]

Might even become a named storm (Antoni).