La Nina: Fairly routine here but anything but for others
La Nina was around for a "second dip" this past winter, and in many cases, it held true to form, even if people's fear of weeks on end of snow turned out to really just be about three days in January and then the week-long fringe-snow fest in March.
A typical La Nina is marked with cooler and wetter than normal conditions with the wetter conditions usually in the fall and the cooler conditions in the winter. This winter was dominated by cooler than normal conditions, but the fall was actually pretty dry. Winter did try to make up for lost time, though.
March is well on pace to be the sixth consecutive month with below average temperatures, but rainfall has been a different story. October was about spot on average for rain, but November and December were considerably drier than normal.
However, once the year flipped to 2012, it was as if the rain remembered where it was supposed to be all this time. January was 1.26 inches above normal and while February was pretty close to average, March is already nearly 2 1/2" ahead and we've still got a week to go!
For the numbers' geeks: October to December had 10.85 inches of rain but January to March had 15.60 inches so far.
Indeed, March has been the most "La Nina-esque" month of the fall and winter as once again, the pattern waited until the peak of winter had passed to really energize. Last year, it was April that caught the brunt; this year it's March. But in that sense, the Northwest really did dodge a bullet for the second year in a row as had the pattern showed up a month or two earlier, the winter would have been a whole lot snowier.
La Nina has also left her mark in the mountains, where late season snows have once again pushed snowpack totals well above normal -- about 120-150% of normal as of March 15. In fact, UW Research Meteorologist Mark Albright says the 254 inches at Mt. Baker is the 6th highest all time since records began in 1927 (although there are some years of data missing in the mid 1940s and mid 1950s and the 1950s had some very cold winters).
But unlike last year, when the entire west coast was enjoying healthy snowpacks -- California and Nevada had record amounts of snow -- this year the bulk of the mountain snow has been confined to just the Pacific Northwest. California's snowpacks are well below normal.
A Crazy Fall and Winter Elsewhere
The biggest story of our winter was the historic ice storm in mid-January, but it seems this fall and winter has left quite a mark in the history books across the world.
Just think, since mid-October:
- * The New England area had a rare October snowstorm
- * Central Europe got stuck in weeks-long snow and ice storm. Rome reported its worst snow in 26 years that dropped as much as 8 inches of snow in some spots.
- * Western Alaska was also a snow bullseye with 18 feet of snow that fell over a couple weeks in Cordova.
- * Hawaii had some of their worst thunderstorms and rain in years, if ever. Some spots got over 40 inches of rain in a week! Amid the storms, Hawaii recorded its largest hailstone on record -- 4 1/4 inches!. The old record? Just 1 inch.
- * La Nina conditions usually do make for an active tornado season and this spring has been no different. Coming off the record 2011 season, there have already been several tornado outbreaks across the MidWest.
- * While New England made news for early snow in October, attention has now turned to the incredible heat wave that has gripped the Midwest and East Coast for much of the middle of March. Temperatures have been reaching the 80s for several days -- in some cases 30-40 degrees above normal and breaking record highs for the day by 10 degrees ore more. Chicago had nine days in a row where they set or tied their record highs, peaking with 85 and 87 degree days.
And according to the Weather Channel, two stations in Michigan broke their all time March high temperature -- for five days in a row! As in it had never been that hot in March before on one day, much less 5. It would be like Seattle having a five day streak of 79+ degree weather in March.
- * Back here in the Northwest, the Seattle area had several days with little pockets of snow, but in Oregon, they were full-fledged snow events. In mid-March, the Oregon coast had anywhere from 1-4 inches of snow -- some spots more! -- in what was a record March snow there. A week later, a bigger snowstorm hit Oregon's Willamette Valley with several inches falling, including a record-smashing 7.5 inches in Eugene!
While La Nina is fading, its effects are expected to linger for a little while longer. The 90 day forecast for April through June is still trending cooler than normal (although average for rain) but as we get toward the summer, forecasts are not picking up a signal one way or the other -- so at least we aren't weighted toward a cool summer. (It does look like the Midwest will be hot and dry for a while though.