Thought it would be a good time to look at the global SST’s and tie in some interesting anomalies which have appeared during the cold second half to winter across the Northern Hemisphere and also look at the deep tropics and potentials with the upcoming Atlantic Basin Hurricane Season.
Firstly, here’s the current global SST’s as of April 1.
There are a few striking ‘cold anomalies’ which really stand out when looking at this chart, look at how much the waters have cooled right along Asia’s east coast and on Japan’s NE coast, keeping in mind the kind of snow season northern Japan has had. Check out how cold the waters are off Canada’s east coast and not forgetting the waters surrounding the UK. All this abnormally cold water is evidence of the very cold March. Check out how cold the North Sea east of the UK and surrounding Newfoundland are compared to normal. You can clearly see three areas hugging each continent at roughly the same latitude which are at least 3-4C below average, indicating where troughs have held with unusually cold air within them. Reason for these abnormally cold waters are thanks to persistent cold NW winds driving off Siberia in through China, Japan and the Koreas as well as off an unusually cold Canada across the Maritime Provinces and bitter easterlies blowing off an unusually cold Scandinavia and Russia towards the UK. Key is all source regions over the heart of these continents were well below normal and the answer as to why is we saw the second deepest -AO index during March since 1948 with 1970 being coldest. The mid-winter level cold was directed into eastern North America, Western Europe and East Asia thanks to a strongly negative NAO.
Also notice the cold anomaly extending from the central Atlantic back into the Caribbean and Gulf of Mexico. It’s been a very cold March over the Southeast US and Florida. The waters have cooled quite a bit over the Gulf and even more so surrounding Florida. As ridges build in this region, these waters will quickly warm and the colder than normal Gulf is having impact on this year’s severe weather season. Although it’s inevitable that the season will ramp up, it’s likely to remain quieter than normal this year. Cooler Gulf equals less heat, high dew point air and ultimately less fuel being lifted north by eastbound Pacific systems.
Compare this to the end of March last year.
Let’s look closer.
April 1, 2013
March 29, 2012
Deep, far reaching troughs and cold northwest winds blowing off the Southeast coast of North America has produced significant large-scale upwelling over the Gulf, northern Caribbean and off the East Coas, extending well out into the Atlantic. ( Upwelling: Winds which blow over water and draw colder water from beneath to the surface). Strong, persistent and truely bitter east winds blowing off continental Europe has significantly upwelled and cooled the North Sea as well as waters surrounding all of the UK and Ireland.
I think the Gulf of Mexico and North Sea are most striking with the North Sea 3-4C below normal this year vs 3-4C above normal last year.
What Influence May These Colder Than Normal Waters Have On Late Spring/Early Summer?
If you live along the Gulf Coast, dew points may be somewhat down on normal values through spring, perhaps early summer but this should be temporary as there is strong warming at this latitude.
As for the US East Coast and coastal areas around the UK and Ireland. Fog may be more of an influence as well as colder than normal onshore breezes which may produce large temperature differences between beach communities and places a mere 10 miles inland.
What Kind Of Hurricane Season May Be Expected With Current SST Anomalies?
The SST profile of the tropical Atlantic is quite different this year compared to last year at this time and unfortunately, the warmer than normal waters from the central tropics east to the African coast doesn’t bode well because the cooler waters extending west nearer to the Caribbean Sea and Gulf will quickly heat up through spring and early summer and therefore one must consider the real possibility of a warmer than normal deep tropics from Africa to the US this upcoming season. This warmer than normal water this year around Cape Verde will likely suggest a bigger year for long track storms. Last year, it was cooler than normal with a lot of DRY AIR due to cool waters being heated but waters that heat and start off warm, moisten the atmosphere above.
Let’s have a closer look.
Last Year
This Year
Also notice the tripole of warm-cold-warm, this has influence in the easterly trade winds but more importantly, the cold February March brought the troughs and colder air further south than normal and so the concentration of warmth is down over the tropics. This heats the ocean beyond normal values and as the energy increases through spring, the atmosphere moistens too.
Last year, a lot of warmth was focused further south and so the ‘warming’ energy was transfered further north, i.e, the greatest anomalies was NORTH of the tropics and so when looking back at the hurricane season, interestingly, much of the activity was further west and NORTH. Systems like to follow where the greatest anomalies are and this year they’re over the eastern tropical Atlantic and once you warm the western side of the deep tropics, one needs to watch out for a big long track year which may be very similar to 2004 and 2005.
BTW, here’s both March 30, 2004 and 2005. Compare these water temp profiles compared to this year and notice the similarities.
2004
2005
One difference this year compared to the same time back in 2004 and 2005 is that the Gulf and waters off the Southeast US are colder, however, the thing that stands out when looking at these charts is the waters off Africa are well above normal and by the time July and August comes around, the Gulf, northern Caribbean and waters off the Southeast coast will be back to normal, perhaps above. That tripole of warm-cold-warm also shows up each time. That theory is frequently mentioned by Joe Bastardi and Dr Joe D’Aleo whom I have learned a great deal from over the past 10 years.
As we press on towards summer, I will show you other key aspects I am looking at regarding the 2013 hurricane season. All in all, this year looks bad and if you live on the Gulf and East Coast, prepare and have a plan in place.
More thoughts will be available shortly.
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