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Pattern Oppressive Ornery Obstinate Opposite October

Storm5 said:
Cold front is knocking on my door . See ya later summer it's been fun but winter will holds my heart !
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Finally. I have been waiting for a long string of cool mornings and right beyond this one isn't a heat ridge, but another cold blast. About time we switch to more cold than warm, until the time it really matters in December through February. :confused:
 
WxSouth has a nice post on FB. Talking about next month or two , and peek into winter. Informative
 
feels amazing here... crisp fall air :) No 90s in the forecast either. I picked a really good week to head down to Central Texas for a couple days lol

Winter is coming
 
Picked up a shower or two this morning, about .21"
 
A wonderful 42 degrees here this morning. We will hit the 30s for the first time this fall tonight.
 
Now that the front has come through, wonder if it gets up there temp wise at all. NWS says no (does say it'll move up but slowly).
 
GaWx said:
When the MJO is 4-5 and outside the circle (moderate to high amp), you may as well assume it won't be cold most of those days and that it likely would be warmer than normal for that period as a whole. But when inside the circle during those phases, the longterm average has actually been fairly close to normal based on overall SE US MJO climo. Of course, the MJO normally rotates several times during winter.

Go here for a writeup about the correlation between MJO phase and KATL Jan temp.'s (as a proxy to SE winter overall):
http://blog.southernwx.com/2017/01/...phase-inside-the-left-side-of-circle-coldest/

Hopefully it will be a weak (ONI peak of say -0.6 to -0.8) rather than moderate La Nina (-0.9 or colder) as that would mean lower chance for a mild winter. Also, hopefully the MJO will be mainly weak, including inside the circle. If we can get a weak La Nina with MJO mainly inside or barely outside the circle for DJF, then the chance for a warm winter would be low.

Edit: I just remembered that you're in Arkansas whereas I'm talking more SE US. So, what I'm saying applies more to your E than in your state per se as my studies have been more SE US concentrated. I'm not so sure about Arkansas as I haven't studied its climo. Keep in mind that ATL is 450 miles away from you and my studies center around ATL.
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I really do not understand the physical mechanism (if there is one) linking weak MJO amplitude to lower probability of BN temperatures at least here in the SE US and thus Im skeptical of this claim and assume it's probably an artifact of the data unless more work is done, esp wrt cross-validation with other MJO indices. Several questions immediately come to mind that question the validity of your argument, namely:
A) Again, what's the physical mechanism or phenomena that can bridge this link you're asserting exists between MJO amplitude and temperature anomalies in the SE US? If there is none, then you can't disprove what you're observing may be merely an artifact of the data or is happening by random chance.
B) The inherent construction of the RMM MJO means it is far from a perfect measure of the phenomena and anything but, and often times Convectively Coupled Kelvin Waves, Equatorial Rossby Waves, TD Type Waves/Tropical Cyclones, Monsoon gyres, and even ENSO can create spectral leakage, effectively meaning that these phenomena often are as falsely projected onto the RMM's leading principal components of OLR, U850, & U200 as an "MJO wave" when in reality, it's actually not an MJO wave, and the RMM index is very notorious for this because these quantities are unfiltered unlike the OMI and VPM... Henceforth, the question arises, how much of the time is the RMM index actually measuring a true MJO wave and how does this compare w/ other MJO indices, and what impact would this "bad" data have on your results (if any)?
C) What impact will the warming background climate have on the viability of your results, and how much is this actually contributing to your results? (i.e. for example, let's hypothetically say there's more MJO amplitude later in the record esp post mortem early-mid 1990s then this could skew the data w/ amplitude warmer because there are more strong MJO events later in the record and vis versa)
D) What are the sensitivity of your results to things like the QBO, ENSO, PDO, AMO, (etc), and utilization of MJO tracers such as OLR, U200, U850, & VP200 (among others)?

"If we can get a weak La Nina with MJO mainly inside or barely outside the circle for DJF, then the chance for a warm winter would be low."
Is it really safe to assume this here especially given a) warming background climate/persistence, b) bias towards +NAO last several years (& this was evident during the warmer climate of the medieval warm period), c) random variability/lurking variables (?), thus even if you were able to back this up with historical data, it still may not be a valid at all because there was no apparent dynamical adjustment for the aforementioned factors (among many others) which will inherently skew the data against the historical "grain" towards a warmer winter here in the SE US

Sorry for the interrogation here, but these are the kinds of questions and feedback I often observe on a day-to-day basis in academia and it's the ability to answer questions like these that allows one to make the leap of faith from research confined the blogosphere to academia and builds confidence in your peers...
 
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Nice eye candy for a departure from normal ... :cool:

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Man, I am loving this weather and am so giddy for this upcoming winter! Thanksgiving, Christmas, college football, and weather model watching! Best time of the year and its not even close!

May be breaking out the fire pit tonight!
 
pcbjr said:
Nice eye candy for a departure from normal ... :cool:

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The GFS seems to keep showing a big cold balst just beyond truncation, but it has made it from the 300s to the 200s, so perhaps it could be a good blast. Of course, the GFS may be a bit too much, as 6Z showed the first snowstorm for many in the Plains and Midwest.
 
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