Biggest WxClimo Story of 2017…Wildfires.

Fires have been raging across the world this year with unprecedented scope. Major wildfire outbreaks have been notable from tropical rainforests in Africa and South America to the taiga of Canada and Russia. Even Greenland has seen an unusual amount of fire activity on the edge of the ice sheet. This year, Western North America, and the Iberian Peninsula of Europe have been particularly hard hit with life-threatening fires (see HERE, HERE, and HERE). Although fires occur every year with variable impacts, a significant upward trend can be tied to climate change allowing both natural and human activity to ignite and expand the destructive intensity of wildfires.

This video by Climate Central summarizes the impacts of these fires so far this year and their connection of climate change. This recent article by The Observer also summarizes fires around the world and the impacts of climate change.

 

(The featured satellite image above is from October 9, 2017 courtesy of the European Space Agency).

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Analysis and Forecast Impacts of Post-Tropical Ophelia in Ireland Monday

Hurricane Ophelia is a high-latitude hurricane by tropical standards…a Category 2 storm with maximum sustained winds of 100 mph as of 11 pm AST…moving south of Azores at 20 mph.

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Analysis of meteorological state around Hurricane Ophelia at 2 am AST. The hurricane is moving south of the Azores island chain and will pass between the Azores and Portugal Sunday morning.

This hurricane, is on track to take its already unusual path northward toward a collision course with Ireland and the United Kingdom Monday and Tuesday!

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National Hurricane Center advisory on Ophelia and it’s path. It’s expected to reach Ireland as a “post-tropical” cyclone…a hybrid frontal system…on Monday. VERY rarely are tropical cyclones, particularly any stronger than Category 1 located in the Northeast Atlantic Ocean.

Not to worry, however. Ophelia will NOT be a tropical cyclone when it arrives in the British Isles Monday. Sunday, the hurricane will begin to pass over much cooler waters between the Azores and Portugal (and note, the hurricane is currently over waters 2-3 degrees C/~3.5-5.5 degrees F above normal). At the same time, if you look at the previous satellite analysis, the hurricane will begin to interact with the existing frontal zone and ingest air from an approaching cold air mass moving in from the North Atlantic. This will begin the process of extratropcial transition where Ophelia becomes a mid-latitude frontal system. However, because of its old, warm tropical air mass, it will continue to retain some of its internal energy, enabling it to be a powerful hurricane-force windstorm.

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European “Euro” Model showing Post-Tropical Cyclone Ophelia approaching Ireland Monday morning (AST). Other global computer models vary the center of circulation either just offshore the west shore of Ireland or make landfall over southern Ireland Monday morning.
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Euro Model showing damaging wind gusts overspreading Ireland from south to north Monday. Models generally agree with bringing damaging wind gusts of 75-85 mph (~120-135 km/h) to the south and southwest coast of Ireland Monday afternoon (local time) with isolated gusts over 100 mph (~160 km/h). Gusts to 60-65 mph (97-105 km/h) with isolated higher gusts to 75 mph (120 km/hr) in the south of the island will be possible across much of the rest of the country into Northern Island Monday evening and night. All surrounding coastal waters will be hazardous for marine interests.

I have moderate confidence in my forecast…some uncertainty deals with the track of the low pressure system. A track farther offshore to the west would limit significant winds to the south and west shores and coastal communities. A track very close or even onshore the south coast would send very high winds deeper inland into Ireland. Regardless, those in the country should expect widespread downed trees, power outages, and difficult driving conditions for high-profile vehicles during the afternoon into late evening Monday.


Here is the climatological history of all known tropical cyclones in the North Atlantic just to show the rarity of systems such as Ophelia. Although some cyclones may have been missed prior to the satellite area, it is possible that such cyclones were less likely to survive in the distant past because of cooler waters where Ophelia is located now. Sea surface temperatures have warmed on Earth because of climate change.

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All hurricane tracks in the North Atlantic (1851-2012). Note, tracks heading to near the British Isles were likely as extratropical systems. Hurricane Vince, however, made a historic landfall as a tropical depression in southern Spain in October 2005.
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Ophelia is over waters 2-3 degrees C above normal. The hurricane will move away from waters favorable for hurricane maintenance during the day Saturday.

–Meteorologist Nick Humphrey