Saturday, 24 February 2018

Catching the Worm

Migration Forecasts 2018, #1

Yep – it's that time of year again....

The end of February is the period when some early birds are already feeling the urge to leave behind the lazy sunshine of west Africa and head for the wet and still-wintry north lands where they will breed. 

A timely start to migration is important for all birds, and adult ospreys in particular. Even though parts of northern Europe may still be blanketed by snow, they can reach staging areas in Spain, Portugal or France where food is available while they wait for Spring to take a firmer hold.

Atlantic low-pressure weather system (c) McMichael 2018
(Click for full-size)
This time last year, these early migrators had a “goldilocks” window to assist them – and this season, the exact same condition has arisen again. This MODIS satellite picture shows a large circulating low-pressure system in the eastern Atlantic. Winds on its south-eastern quadrant are swinging round to create the long-distance coastal flyway up through Mauritania and Morocco, while still leaving open the Gibraltar straits, where wind speeds will be light.

Running the forecast models a bit further on reveals that a second Atlantic low is developing behind the first, and the models suggest that it will be on the same track. Unlike 2017, this means that the migration “window” could remain open for much longer – possibly out to the 5th March and maybe even beyond that.

GFS model forecast for 25 Feb 2018.        (Click for full-size)

It will be interesting to see what kind of reports come in from the key watch points over the next ten days or so.

Kielder Forest Partnership

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