Long Range Update: Pattern Evolution Through February…
Updated 01.28.22 @ 7:32a
You must be logged in to view this content. Click Here to become a member of IndyWX.com for full access. Already a member of IndyWx.com All-Access? Log-in here.
Updated 01.28.22 @ 7:32a
You must be logged in to view this content. Click Here to become a member of IndyWX.com for full access. Already a member of IndyWx.com All-Access? Log-in here.
Updated 01.20.22 @ 10:18p
The Madden-Julian Oscillation (MJO) is forecast to remain in the neutral, or “null, phase into early February. Phase 8 did the “dirty work” on helping drive a more persistent cold pattern into the eastern United States prior to moving into the null phase.

You know the drill, that means we will lean on the teleconnection blend to formulate the baseline of the upcoming 2-4 weeks. During the middle of winter, we lean heaviest on the AO, PNA, and EPO. (The NAO will be more strongly factored into the equation during the late winter and into spring).



2 out of 3 of the big teleconnection drivers favor cold to wrap up the month and open February. The one fly in the ointment? The strongly negative PNA. With that said, if we can, indeed, get the EPO and AO to come to fruition, it’s a stormy, cold signal as compared to what we saw back in December.
Thinking here is that headlines during the Weeks 1-2 period will continue to be dominated by cold before some moderation of the cold allows an increasingly stormy signal to grab the attention in the Weeks 3-4 period. Far too early for specifics, but more in the way of moisture-laden systems should emerge beyond next week.


While we still are in the cold camp to open February, pressure will be put on the pattern that should drive more eastern ridging once out of the 1st week. Accordingly, the pattern should flip towards more of a persistent above normal regime roughly between Feb. 7th and 14th. Above normal precipitation would also be favored into the 1st half of February.




Updated 01.14.22 @ 7a
The primary driver (the Madden Julian Oscillation, or MJO) will be in a favorable phase to allow colder than average temperatures to take up residence across the eastern part of the country as we close out January. To no surprise, these particular phases favor positive heights over the high latitudes (blocking) which helps drive more of a persistent colder than normal pattern.




We’ll keep an eye if the MJO gets stuck in the neutral phase, but the “loop” around into Phase 6 this time of year would continue to favor cooler (to colder) than normal conditions across our portion of the country.
That brings us to our teleconnections. The “big 3” (this time of year include the AO, EPO, and PNA) are also all in favorable position to deliver a colder than normal pattern to close January.



One could also build a case that February would at least open colder than normal based off a combo of the above (MJO and teleconnections) and we agree with that idea, but do believe a “flip” in the regime is ahead after the first week, or so, of the month to milder times.
To no surprise, modeling is showing this cold close to the month.

The opportunity is present for Week 2 to be bitterly cold, as the European is hinting above. Sub-zero temperatures are on the table, especially if we can get some snow down.
Speaking of snow, this pattern should produce a couple opportunities for central Indiana to get in on the act before the end of the month, or beginning of February. Despite the incredibly slow start to the season, take any one particular solution with a grain of salt when looking at operational guidance 2 weeks out.
Updated 01.09.22 @ 8:30a
You must be logged in to view this content. Click Here to become a member of IndyWX.com for full access. Already a member of IndyWx.com All-Access? Log-in here.
Updated 01.06.22 @ 7:20a
You must be logged in to view this content. Click Here to become a member of IndyWX.com for full access. Already a member of IndyWx.com All-Access? Log-in here.