Thursday, January 18, 2018

January 23-27 Potential Winter Storm

This is a brief update to the previous post concerning this possible winter storm, which you can find here.

Tropical Tidbits
Shown above is a near-analysis of the meteorological environment over eastern Asia for the morning of January 17th. At this time, we saw a storm system skirting the eastern coast of Japan, intensifying somewhat as it did so. As I highlighted in my previous post, this will pose a threat for a winter storm in the January 23-27 period.

I maintain that the Midwest/Ohio Valley regions continue to have a better chance of seeing wintry impacts as opposed to the East Coast, but long-range model guidance suggests the Plains may be able to get in to the mix, as shown below.

Tropical Tidbits
This 210-hour forecast from the GFS model has a sub-1000 millibar low pressure system moving north through the Plains, laying down accumulating snow in the northern Plains, with showers and thunderstorms likely occurring in portions of the Midwest down to the Gulf Coast. As is the caveat with any model forecast beyond 84 hours, this is bound to change, and likely will do so drastically. That's why long range model guidance is used more for identifying the *signal* of a storm, not yet the exact location of such a storm. As such, it is a good sign for those hoping for some stormy weather that the GFS is sniffing out such a possibility in this January 23-27 timeframe.

Tropical Tidbits
To exacerbate this point, above is the Canadian CMC's model interpretation of this storm. It predicts the storm will crawl near the Gulf Coast, impact the Southeast and eventually ride up the East Coast. That flies directly in the face of what I said earlier here, but I'm posting it to highlight how these model forecasts will drastically change in coming runs, as is typical. Again, the point is that the model is sniffing out a storm at all- the path will be refined in coming days.

Tropical Tidbits
Just to entertain all crowds, the ECMWF model above shows this storm cutting up through the Ohio Valley, though slightly outside of this timeframe. Details will be sorted out, but model guidance is latching on to the idea of a winter storm around the January 23-27 timeframe.

To Summarize:

- Model guidance is sniffing out the potential for a winter storm in the January 23-27 period, as was highlighted in a previous post from January 10th.
- Significant uncertainties exist with regard to the location of any wintry weather, and such impacts will not be known with any degree of accuracy for at least a few days.
- For now, the Midwest/Ohio Valley/Plains regions look most likely to see impacts, but this comes from the synopsis of the atmosphere back on January 10th and these locations could very well not be affected by this system.

Andrew