Climate "singularities" (warm, average, warming, temperature)

[markovian process]

I came across this concept reading about climate sometime ago, perhaps in a book, so I thought to look it up.

There is this idea about weather phenomena happening very regularly and reliably each year, around a certain time, sometimes to the level of predictability of even a week or two or on the scale of days. Some people argue that these are real but others think they're statistical flukes. I think it would be cool if they are real and would like to know more about possible causes.

Singularity (climate) - Wikipedia, the free encyclopedia

Singularities developed for the British Isles | Weather FAQs

For those of you familiar with climate and weather, what are your thoughts?

Do you know of any processes that might lead to consistent weather events to happen each year on this time scale? A lot of predictable climate phenomenon span the scale of months (eg. winters colder than summers obviously because of earth's tilt plus seasonal lag etc.) but can there be something deterministic enough to note on the scale of a week or days?

[markovian process]

Does anyone know even just a bit about this? I'm still curious.

[Ethereal]

We get more dry conditions (that bring bushfires and dust storms) early into spring in Sydney rather than in the actual hotter months of summer.

Does this count?

[Rozenn]

We have something similar to the January "thaw" in France. On average, the first week of February is warmer than the surrounding ones. It's the only time of year when the temperature curve reverses for more than a couple days. I wish I could find the graph (mean temperature in the whole country for each day of the year).

Just a supposition, maybe that has something to do with the frequent sudden stratospheric warmings (SSWs) that occur from mid-January on? The 65-90N mean temp at 50 hPa rises a lot ofter mid-Jan (green curve):
http://s3.amazonaws.com/dk-productio...gif?1358347725

Stratwarmings weaken the polar vortex. So, often, a week or two after a SSW, the zonal flow weakens, the jet stream buckles and cold air bleeds into lower latitudes. Meaning the return to colder conditions after a slight warming in mid-latitude locales? Or most likely not...