La Nina: Still alive and hanging around through spring again
One thing the recent snow and ice storm did besides knock out power and rewrite record books was to quell the nearly steady diet of emails wondering where La Nina went and if she'd ever show up.
The truth was, she never left despite the rather pedestrian November and December and is still here. And the latest weekly forecast maintains La Nina conditions will persist into spring before we drift back to neutral status.
The latest observations show the cold temperature anomaly in the part of the Pacific Ocean that matters is -1.1C with a running 3-month average of -0.8C. La Nina is considered anything colder than -0.5C.
The -0.8C average is the coldest reading so far of this second go-around La Nina, but it's not as strong as it was this time last year (-1.4C).
This chart shows how we've been holding steady in a solid La Nina pattern since mid August:
But for those of you who have a (snow) shovel still in hand waiting to bury La Nina, forecast models indicate you'll soon have your chance. (Or maybe "soon" should be "eventually", depending on your definition.)
One group of models have La Nina gradually weakening from here on out, officially becoming "neutral" around the middle to end of spring and maintaining neutral next fall.
A second group of models -- one that correctly predicted the return to La Nina this year when other models were going neutral -- also agrees that we'll go neutral and perhaps even borderline El Nino by the end of summer.
What does that mean for us in the short term? Well, in the really short term, we're going back to another long bout of dry, foggy weather as has seemingly been the case to start the first two weeks of every month since November. So those with short term memories might start to question what happened to her again.
But the snow season holds through about the first week of March around the Northwest, so we're not out of the woods for getting a third round of winter weather this winter. It just won't happen any time soon.
As for once the snow season is dead, the long range models for spring are trending once again toward a cooler and wetter than normal period which would be the third year in a row and a hallmark of a continuing La Nina:
Though you can take some solace in that those maps are nowhere near as intensely adamant about the cooler/wetter pattern as they were last year.
So to recap: Another dry stretch is in the offing, but don't think that we're going to stay dry forever.
OMG! It's a neutral winter!
I have had a few ask me what to expect in a neutral winter.
To be honest, I'd actually put forward this current winter as a good example. Neutral winters tend to run the gamut between dry stretches (check), cold stretches (check) and warm, wet stretches (check) -- sort of a like a wide potpourri of weather without La Nina (cooler/wetter) or El Nino (warmer/drier) to pull the winter one way or the other. The fact that this winter has been more neutral in character than a traditional La Nina winter indicates to me that this year's La Nina has been fairly weak.
Note that La Nina and El Nino really don't have much of a signature of affecting our summers one way or the other so those are a bit more random.