NOAA predicts warmer, wetter than normal winter
Predicting whether winter will be cold or warm, wet or dry is an extremely difficult task. Indicators from years past are a good way to know what to expect. Climatology lets us know what to expect in terms of temperatures and precipitation in normal conditions, but if this past summer is an indicator — conditions can stray far from normal.
Long-range forecasting is also extremely difficult and often inaccurate. Meteorologists know that a forecast for a certain day a week away seldom pans out. In Alaska, that change in a forecast can occur in a matter of hours due to the unique geography and location of the 49th state.
By using general trends and climate patterns, a long-range weather pattern can be predicted.
Think of it like a cup of coffee. Leaving it alone keeps it black, and it tastes as such. Adding sugar might change the taste but not affect the color, but adding cream changes the color, taste and temperature. While it might be difficult to say what will happen right when the cream or sugar is added, it is easy to know the general outcome. Cream and sugar will make the coffee easier to drink for many.
ENSO plays a role in determining the seasonal pattern as a whole, while the MJO and AO play a bigger role in weather each week.
The Madden-Julian Oscillation can impact how much moisture is in the forecast from week-to-week or month-to-month. The Arctic Oscillation is what causes Arctic airmasses to spill south. It can determine how many cold snaps we see but can't predict an overall pattern.
The presence of an El Nino or La Nina changes weather throughout an entire season. Right now, there no El Nino or La Nina. Temperatures and precipitation would trend close to normal with that weather pattern, but there is more at play here.
This past summer will play a role in determining our winter weather.
The biggest factor in seeing above-normal temperatures is the lack of sea ice around Alaska. This allows the relatively warm water surrounding Alaska to warm the state into the winter months.
Similarly, temperatures have been trending above normal since this summer’s heat wave. October has frequently seen high temperatures 5 degrees above normal, a trend we will likely see continue.
This winter will likely be wetter than normal. Without El Nino or La Nina, weather patterns will stay somewhat normal. The difference will come from the warmer temperatures.
Warmer air holds more moisture. That means each individual storm can pack a bigger punch as it moves in.
Don’t let this warm forecast get you down. For much of Alaska, warmer than normal temperatures will still be below freezing. That means much of that increase in moisture will be seen as snow.
Correction: An earlier version of this article incorrectly stated Alaska had its warmest summer on record.
Copyright 2019 KTVA. All rights reserved.
MORE FROM THE KTVA WEATHER TEAM: