Mild and Relatively Boring Winter Thus Far ~ Does Second half of Winter Still Look Busier (or Back-end Loaded)?

It's been a mild and slow winter in regards to snowstorm activity in Southeast Lower Michigan. How were the analogues in regard to the the winter thus far?

From my Outlook:

I look for a normal to above normal temperature winter. This is both for the winter (Dec-Feb) and cold season (Nov-Mar).  With the variability in these type of La Nina's; leaves me with a two-tier temperature forecast - normal to above.

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We're good here as temperatures have generally been normal to above normal with a mild winter overall.  The mild weather has actually been an overachiever this winter so far and I expected it to pull back some through February. I underlined overall since that doesn't mean the winter wouldn't be without its cold snaps. In fact; sharply colder air masses were introduced from time to time and more likely the second half of the winter.

 

From the Outlook 

 

In descending order; back-end loaded (roughly late Jan-Mar) winters were favored in regard to colder temperature and/or heavier snowfall.

 

Snowfall prognostication this season is more problematic than precipitation as a whole since storm tracks affecting the region will be north, over Southeast Lower Michigan and south over the Ohio Valley. This leads to snow, rain, rain to snow, snow to rain depending on the system. The unusually strong mid Pacific jet (for a La Nina) will lead systems to bring in milder Pacific/Gulf of Mexico air and thus; mixed precipitation should be a frequent visitor. 

 

In descending order; back-end loaded (roughly late Jan-Mar) winters were favored in regard to colder temperature and/or heavier snowfall.

 

And one more thing; there are enough well below normal (or "snowless") months that showed up in every set of analogues to be concerned about a bust on the snowfall prediction but I'll hang tough with the normal to above normal; for the time being anyway.

 

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Snowfall -and actually precipitation on the whole- has been more problematic thus far through January 30th with below normal precipitation and snowfall across the entire region. This is unusual for La Ninas but we still have 2 1/2 months. But then again; in back-end loaded winters, you'd expected that the winter precipitation would be off to a slow start. In keeping with the forecast of a back-end loaded winter; we'd look for a pickup in storms. I think we finally are beginning to see that this last part of January. A two tier seems most suitable in keeping with the normal to above.

So what's been happening meteorological-wise (maps) and what's it looking like the rest of the winter?

 

Well one thing that has evolved the past few months has been the positioning of our La Nina. We started the winter season with a east-central seasonal La Nina (generally normal temps, above normal precipitation) which has evolved to a central-west La Nina (above normal temps and above normal precipitation). Note that the La Nina area considered is a rather narrow area over the Pacific.

Last 3 months stream of the SST (note the colder, dark blue waters migrate west in the La Nina region with time)>>>

Updating the positioning of the La Nina from seasonal winters to mild winters positioning.

 

Updating the Winter and Cold Season Forecast

Temperatures

As stated; this mild winter scenario actually plays into the Winter Outlook. And, I see no reason to drastically change it. In regards to the original temperature forecast departure;  Temperatures - Normal to Above (or -1.0 to +2.5 temp departure); however that range can be raised and tightened to just above normal. 

 

I look for both the entire winter and cold season temperatures to average above normal over Southeast Lower Michigan with a departure of +1.5 to +3.0. Regardless; I'll keep the temperature trend for the remaining part the winter and cold season (through March) with colder and closer to normal. That being said; I see no reason to dismiss the strong westerlies off the Pacific (and one the main reasons we've been so mild) which will be at least part of the equation into spring. This does bring the potential prospect of a more active spring severe weather season than seen the last several years.

Precipitation (Rain and Snow)

One of the memorable forecasters I worked with much of my career used to have a saying "let's give the forecast time to work" and I believe this is one of those times; at the very least the snow part of the precipitation forecast. My original forecast read as follows; 

 

"In descending order; back-end loaded (roughly late Jan-Mar) winters were favored in regard to colder temperature and/or heavier snowfall. Potential for a major snowstorm or two in the snowy La Nina analogues was slightly greater in every month Dec-Mar with a lean toward late season".

Still keeping with that view and original forecast; I look for snowfall to average around normal (departure -5.0 > +5.0) to locally above (departure better than +5.0). for the entire snow season.  

 

Now entire precipitation (rain/freezing rain/sleet/snow) has been problematic also with below normal amounts thus far. This is unusual for a La Nina which generally by trade is wetter than average. 

 

Original forecast for precipitation:

Precipitation - Above

Analogue guidance and computer model guidance from numerous sources overwhelmingly call for a wetter than normal winter.

 

I do feel with the increase in activity we'll make up some precipitation but still I'm inclined to drop the category to below (1.00" or more below normal) to around normal ( or -1.00" > +1.00") for the winter and cold season.

 

Look for forecast on notable storms/trends/patterns to continue on Facebook and here into spring. Keep those snow blowers/shovels handy.

 

BTW ~ Take a look at the Jekyll/Hyde Winter of 1899-1900 as an example of what started out as a boring, slow winter through January that picked up with a vengeance the second half!

https://weatherhistorian.blogspot.com/2011/12/dr-jekyll-mr-hyde-winter-of-1899-1900.html?showComment=1612024152410#c6423598471122289426

 

Making weather fun while we all learn,
Bill Deedler - SEMI_WeatherHistorian