Brian Bledsoe

Happy New Year Insiders! 

La Niña Update:
First, the map below shows the precipitation anomaly in inches during the past
30 days. 

Besides drought having already been entrenched, most of Eastern Colorado, and
the Western High Plains have actually been ok, during the past month. Our
mountains have struggled, as have many in The West. Notice how dry it has been
in Northern California and the Pacific Northwest. This is pretty
uncharacteristic of a strong La Niña, but remember, this La Niña is a little
different flavor. The other region that is deal with an uncharacteristic pattern
is the Southern Plains. This includes a big storm that just impacted most of
Texas and Oklahoma with significant rain, snow, and ice. Is this an aberration
or indicative of the pattern that will continue? We'll examine that later.

While the North Pacific has continued to cool in the last week (first image), it
still remains warmer than average (second image).



Typically, a strong La Niña would offer cold in the Central and Eastern Pacific
as well as in the North Pacific. Not so much this year, and that is something we
have been talking about for quite some time now. 

Is this setup likely to continue? Probably, and we see no real reason for the La
Niña to weaken or go away. In fact, the Southern Oscillation Index is at its
most positive in almost a decade. 

As a reminder, a very positive SOI is indicative of a robust La Niña that is
coupled with the atmosphere and likely to continue. Notice that the last time
the SOI was this positive was in late 2011 and early 2012.  Drought was an issue
for many then, and it remains an issue for many right now. The latest Drought
Monitor confirms as much:

Most models continue to forecast the La Niña episode to continue. The graphic
below shows various models and their forecasts.

As you can see, most model solutions do not have us coming back to "normal"
until very late spring or early summer. This is no surprise, and some model
solutions do linger it for a longer period of time. 

NMME Model Precipitation Forecast

January

February

March

April

May

June

July

You can see from the above maps, that the areas that are currently suffering
from significant drought, are the most likely to continue to suffer. The fact
that the stout dry signal lasts into the spring for many, is very concerning.
Snow pack isn't great for most areas in the Rockies, and if we don't see a good
boost in the next month or two, that lack of spring snow would likely pave the
way for an early and potentially nasty late spring and summer of wildfire. I am
somewhat optimistic that La Niña could deliver some much needed snow to some
areas that need it, but the next two weeks places said moisture, where it is
typically found during a La Niña.

NMME Temperature Forecast

January

February

March

April

May

June

July 

It is no surprise that the model is forecasting pretty much everywhere to be
warmer than average. The exception will be areas that get involved in the storm
track and stay there. I am particularly interested in where the strongest warm
signal is located. It resides mostly over areas that are dealing with the worst
drought, the southwest part of the country. Drought feeds drought, and the
longer we continue to go without a significant uptick in snow, the more the
drought will deepen and have a strangle hold on the region.

Status on La Niña and Latest NMME Model Outlook