Category: PNA

Jan 24

Long Range: Cold Pattern Isn’t Going Anywhere Fast…

We’ll save our short-term discussions for the severe and high-impact arctic outbreak on deck and focus our attention in this post to the upcoming several weeks. In short, we don’t expect the cold pattern to break anytime soon. Could there be a day or two of “relaxation?” Yes, but from an overall perspective, confidence is higher than normal on the colder than average pattern continuing through the month of February.

Let’s dig in to the teleconnections:

EPO

AO

NAO

PNA


Given the teleconnections in agreement pointing towards a cold pattern, it shouldn’t come as a surprise that the majority of data is also on the cold train as we flip the page into February:

CFSv2 Weeklies

Weeks 1 & 2

Weeks 3 & 4

JMA Weekly

GEFS

While we aren’t licensed to show the European Weeklies, the new update runs with a cold pattern into early March. This falls in line with the overall consensus of longer range data, backed up by teleconnections.

Though not nearly at the amplitude of a few weeks ago, the MJO (Madden-Julian Oscillation) is forecast to move through Phases 5 and 6 in the coming weeks before going back into the “null” phase.


Phases 5 and 6 this time of year would suggest colder anomalies are more likely around our neck of the woods:

Given the above, we continue to think a colder than average “2nd half” of winter looms for the region. We lean heavily on the NAO, EPO, and AO state(s) this time of year and all would point towards a cold time of things moving forward, overall. The latest European Weeklies are interesting from a couple of fronts- initially very cold and then progressively stormy. The idea here is that we remain quite wintry through February and into early March before this pattern breaks. While we may not see a “repeat” visit of the Vortex, it wouldn’t surprise us to see another major arctic outbreak again this winter (after next week), but that likely comes later, and towards the end of the game before we snap into spring.

Buckle up; we think we have a long way to go this winter…

Permanent link to this article: https://indywx.com/long-range-cold-pattern-isnt-going-anywhere-fast/

Jan 10

VIDEO: Long Range Update; And Looking At This Weekend’s Snow Storm…

Tonight’s video update focuses on the long range and reviews some of the fresh short-term data churning on this weekend’s snow storm.

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Jan 04

Trying to Answer Questions When Winter Will Show Up…

Daily, we’re receiving questions around if and when winter will show up. While admittedly later than originally thought here, we’ve never been in the camp of “throwing the towel” in on winter. Our winter outlook that includes below normal cold and near average snowfall remains unchanged.

Before we get into some of our reasons why we think winter will show up (and likely make up for lost time), the upcoming week will remain much warmer than average.

We’re tracking (3) storm systems that will deal the region rain over the upcoming week:

  1. Southern IN this afternoon and evening
  2. All of the state Monday
  3. All of the state next Friday into Saturday

As a whole, rainfall amounts won’t be particularly impressive for most, with 7-day totals between 0.25″ to 0.75″ for central portions of the state. Heavier amounts can be expected across southern areas.

Now, let’s look ahead to some potentially colder times. Before moving forward, it’s important that we recognize models have attempted once already to drive in a wholesale pattern change to colder (originally thought to be underway now). Perhaps it’s a case of “delayed, but not denied.” There’s a lot going on behind the scenes:

  • Sudden stratospheric warming event and potential polar vortex displacement, etc.
  • SOI flipping from a Niña-like state to one we’d expect to see associated with an El Niño
  • Active MJO remains

There are significant changes brewing in the arctic/ higher latitudes that have to raise an eyebrow at the very least.

Today

Mid-January

Note the higher pressures building over the upcoming 10-14 days in the arctic regions.

Not surprisingly, the models begin to tank the AO.

The PNA rises…

Something that also lends credence to a potential pattern shift is the recent SOI drop.

This would tend to suggest that an active storm track may be in place as the more bonafide cold shift is underway.

The moral of the story? Despite the milder period being extended a couple weeks longer than originally thought, there’s still a lot on the table this winter. It’s far too early to think winter’s over before it’s really even begun for most. We expect to see increasingly wintry conditions show up around the middle of January…

Stay tuned.

Permanent link to this article: https://indywx.com/trying-to-answer-questions-when-winter-will-show-up/

Dec 25

Looking at the Holiday Week and Ahead to January…

Tomorrow will be a rather uneventful weather day across central Indiana, but things will begin to change as we head into Thursday.

An area of low pressure will track out of the central Plains into the Great Lakes by Friday. The end result will be increasing coverage of showers Thursday afternoon and perhaps even a rumble of thunder Thursday evening.

Most of the concentrated rain should come to an end around dark Thursday. By that time we forecast a general 1/2″ to 1″ to fall in area rain gauges.

More seasonable air will blow in here behind the storm system and we’ll have to keep an eye on energy “attacking” from behind over the weekend. With colder weather in place, snow is possible next weekend.

Looking ahead, a combination of ingredients appears to be coming together to create a rather significant transition in the pattern as we head into January. Note the developing positive PNA…

This will result in more sustained below normal temperatures making a return early January to our neck of the woods…

Additionally, it also appears an active storm track will continue. While impossible to say this far in advance, prospects for above average snowfall (average is 8.6″) appear likely through the month of January.

Permanent link to this article: https://indywx.com/looking-at-the-holiday-week-and-ahead-to-january/

Dec 20

Deeper Look Into The Long Range…

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