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…

Blizzard-Like Conditions Develop This Afternoon Into Tonight…

While warm air advection (WAA) created an added challenge this morning (freezing rain north of the city, itself, and rain south of I-70), colder air is working south late this morning and will result in a changeover from freezing rain/ rain to snow over the next couple hours from north to south.

We expect the transition to snow to take place in and around Indianapolis between 1p and 2p.

As upper level energy tracks northeast this evening, strong frontogenesis will help a “deformation band” expand in coverage and intensify across the state.  This will lead to elevated snowfall intensity as the afternoon gives way to evening.  In fact, snowfall rates will likely approach 1″/ hour across central and eastern portions of the state at times during the mid-to-late afternoon and into the evening hours.

8p forecast radar.

As this is taking shape, winds will also begin to crank this afternoon and evening.  Gusts in excess of 50 MPH are expected across central and eastern regions- including Indianapolis.

Obviously this will create concerns for power outages, but the other major worry is for developing blizzard-like conditions and whiteouts through the late afternoon into tonight.

As for snowfall totals, the consensus of latest 12z data continues to support our updated snowfall forecast from this morning.

We’ll have additional updates later this afternoon here on IndyWx.com and on our social media accounts.

To close, we highly encourage not traveling this afternoon.  Conditions are expected to rapidly deteriorate as we move through the next several hours. For many across central and east-central Indiana, roads will likely become impassable by evening with the combination of severe wind gusts and increasing snowfall rates.  Major problems from blowing and drifting snow are expected.

More here in a bit!  Stay safe!

Winter Storm Update: Significant Impacts Still Expected Later Today…

While the “1st half” of the storm certainly has been a challenge, we still anticipate a high impact situation to develop this afternoon into tonight across the region.

Our updated snowfall forecast:

Saturday morning video update breaking down the details: