2019 Looks To Come In Just As Untamed As 2018 Has Been Most Of The Year.
2018 certainly has been anything but tame. From Tropical Storm Alberto, Hurricane Florence, and Hurricane Michael, along with all those other "unnamed events" many in our viewing area have seen the wildest year of weather on record. Whether it has been destructive flooding, damaging winds, paralyzing ice, or crippling snows we sure have had our hands full. Many areas just blew their record yearly rainfall out of the water with this last storm event that dumped 2-5 inches of rainfall across the foothills. We will have our top ten weather stories from 2018 to close out the final week after Christmas. Its easy to forget that the weather doesn't change just because the calendar turned a year older.
Looking ahead it doesn't look like the weather patterns will relax any. A weak El Niño remains in play that will likely continue to deliver multiple rounds of precipitation into the Southeast United States. This pattern really has the chance to become very interesting going into Mid and Late January. There are signs that the Pacific North American Oscillation will become positively tilted a few times in January, likely starting the first week of the year. That positive tilt means that a high pressure ridge builds out over the Eastern Pacific or the US West Coast. Heights rise under that high pressure and shots of cold air dump into the Eastern 2/3rds of the US. How cold that air is depends largely on how strong and how far North that ridge of high pressure builds. Long range forecasters across the globe are watching a phenomenon called sudden stratospheric warming that models are predicting will occur over the North Pole.
Now, no the earth isn't falling apart and the stratosphere isn't breaking. Sudden stratospheric warming occurs in the Northern Hemisphere during Winter and is where the stratosphere warms 50° C (90° F) in the course of just a few days. It is caused when the northern jet stream becomes disturbed by other natural weather patterns in the lower atmosphere (ie. troposphere). It takes very strong waves of energy in the troposphere for them to move up into the stratosphere. These waves are developed by air moving up and over natural geological structures, like mountains. Below is a great graphic from @NOAA showing the different layers of earth's atmosphere. The atmosphere normally cools with height up to the Mesopause, and Earth's Mesosphere is its coldest layer.
El Nino is a teleconnection out over the Equatorial Pacific Ocean. When waters in the Equatorial Pacific are warmer than normal it is known as El Nino. When waters are cooler over the Equatorial Pacific Ocean then we call it La Nina. In El Nino scenarios since the water is warmer than normal it is more buoyant. Through the evaporation process that water becomes water vapor. It is transported into The Gulf of Mexico and United States where it interacts with energy in the Southern Jet Stream making the energy moisture latent storm systems.
There are good indications now that
Now, those that have followed us for a long time know that we do not like to overhype things. Being a Meteorologist and having Winter as your favorite time of year can be exciting on one end of the spectrum, yet very painful to watch on the other end. In years when the pattern becomes flat with a zonal flow set up, things can get pretty boring in winter weather forecasting. Working in Emergency Management though and seeing an active pattern shaping up means that there are many, many, sleepless days and nights ahead. That active pattern is what we are watching for to develop through January though. As storm systems with enhanced moisture, thanks to the weak El Nino, undercut the ridge of high pressure over the Eastern Pacific look at an increasing risk of high impact winter weather events across the Eastern 2/3rds of the country. While this all will likely begin the first week of January the pattern could sustain itself time and time again going through the upcoming month. Just two weeks ago we saw our first taste of what happens when cold air interacts with moisture latent systems. We get big winter storms. Now every storm will likely not be in the form of winter precipitation but I do believe that there are multiple winter storms ahead of us in Western North Carolina.
Nothing is concrete though, I mean nothing long range in weather is. Right now we are just in phase 1 of forecasting this pattern that COULD continue to produce many storm systems across our area. We first have to forecast the pattern. From there we will forecast each individual system inside seven days and disseminate our forecasts to you in a timely manner so that you can have time to prepare for it's impacts.
In summary today our goal is to tell you to remain weather ready should another winter storm affect our area. There is no set storm in play that we are forecasting. Right now it is just a pattern. It is a pattern though that this winter weather meteorologist is excited about.
HAPPY HANNUKKAH AND MERRY CHRISTMAS!