SO MUCH FOR THIS ROUND OF SIXTIES...

It's not very often when you have every reporting station in Iowa in the 60s November 10th. Yet, we did it with ease Tuesday with statewide highs ranging from 63 to 68 degrees. Adding to the overall stature of the day was abundant sunshine and dry air. You can see we weren't the only ones enjoying warmth with about 95% of the nation experiencing above normal readings. A big assist goes to the raging El Nino!

Here's what the afternoon looked like from a satellite perspective. Split flow dominates the nation with and cold air locked up in Canada in the northern stream. The subtropical or southern stream jet is displaced over the deep south leaving much of the country high and dry.

WIth the split flow pattern in play, you can see on the national radar how quiet it was across the country Tuesday evening.

Despite the overall lack of weather Tuesday evening, my local area will be one of the few places Wednesday that will at least have a chance of seeing some rain. A clipper type disturbance will send a compact surface low through southeast Iowa Wednesday morning. Moisture is meager but the track of the system and its dynamics should be able to develop a narrow short lived swath of rain that catches all but the far south. As you can see, rain totals are generally 1 to 2/10ths of an inch. A sliver of heavier amounts of 2 to 4/10ths of an inch is possible near the track of the clipper from Cedar Rapids to the Quad Cities on to Peoria.

Not only will the clipper bring some rain, it also carves out a deep east coast trough that drops temperatures significantly Thursday and Friday. Wednesday is a transition day with the clipper passing in the morning turning winds to the northwest. Highs will range from the low 50s north to perhaps 60 again in the south where the warm sector makes a morning appearance. Come evening temperatures will be back in the range of 45 to 50 on the way to lows of 35 to 40.

Strong cold air advection Friday yields minimal temperature gains with highs of 41 to 45. Friday morning wind chills will be at the lowest levels of the season so far around 18 to 24 degrees. Not looking forward to that!

As the east coast trough gradually lifts out over the weekend, highs will slowly but steadily warm once again and you guessed it, we go back under the influence of Pacific air early next week. That easily gets us back into the 50s, perhaps even 60 for a day or two in the south. After that, the GFS is really bullish on a push of cold air that it shows producing a high of only 27 November 23rd.

The GFS gets there by phasing the northern and southern streams and developing a closed upper air low over the SE tip of Iowa the 23rd that looks like this. That's a very impressive looking ball of energy.

The cold core system is shown producing temperature departures as much as 27 degrees below normal in Missouri the 23rd.

The system also produces some snow that is shown accumulating.

WHAT COULD GO WRONG?

What the GFS shows is a very aggressive solution that is driven be another round of phasing between the northern and southern stream jets. One of the biggest issues models have, especially in El Nino years is coupling the two jets. At this distance I would not bet on seeing something as impressive as what the GFS is indicating. In fact, if the northern stream does not engage, the cold air will not be there to produce such a strong storm, snow, or temperatures as cold as its showing.

One thing in favor of some sort of storm and colder conditions is the EPO (eastern Pacific Oscillation) which takes a strong negative turn.

The Pacific North America Oscillation meanwhile is shown in a positive mode.

The two highly teleconnect to another deep eastern based trough that argues for a healthy cool down around the 23rd of November, a time frame we've been targeting for a colder and more stormy pattern late November into December. Tuesday's mean of the EURO weeklies is still aggressive with the snow it shows falling between November 23 and Christmas day.

What I am pointing out is that if you believe the teleconnections, the system the GFS shows fits the pattern and is plausible. On the flip side, that phasing process is absolutely critical for it to happen. I would say at this point the odds of fully phasing are no better than 50/50, meaning what the GFS is indicating is low confidence 12 days away. It's very intriguing to look at but far from certain. For now, the focus over the next few days is whether or not this is a real trend or phoney baloney. All we can do is wait and see how things evolve and I can tell you in the last run of the EURO, what I saw was no where near as amplified as the GFS.

That's enough speculation for one post. Until next time, roll weather...TS