Sunday, November 8, 2015 1:50 PM

Firsthand Weather’s Final 2015-16 Winter Forecast

Matthew Holliday

As I have expressed on a continual basis since I released my early winter forecast in July, this upcoming winter forecast is going to be more challenging to “get right” than the prior two winter forecasts. Based on what you have likely heard on TV or seen on the Internet, you may be tempted to believe that the opposite is true. At this point, almost everyone is aware that a strong El Niño has continued to strengthen throughout this year and is currently rivaling the strongest El Niño ever recorded. Sea surface temperatures remain very warm across the central and eastern equatorial Pacific, which will have a strong influence on the upcoming U.S. winter. However, you must be aware that there will be a few very noticeable differences in sensible weather across the U.S. compared to previous strong El Niño winters.

Special Note: While doing the write-up for this forecast, I quickly realized that the detailed analysis that I also planned to include, which has all of the meteorology behind the forecast, was going to make this forecast way too long. What I plan to do now is post that on the site in a couple of weeks. Especially for the meteorology-savvy folks out there, I realize that certain aspects of this forecast may seem “weird,” which is understandable. In the meantime, please refer to my detailed analysis that I posted for my early winter forecast on the site in July, keeping in mind that some changes have been made since then.

Firsthand Weather’s Final 2015-16 Winter Forecast:

Final 2015-16 Winter Forecast

“Tidbits” Of Important Info:

Before I get into the discussions for each region, I want to briefly discuss some of the more noteworthy changes I’ve made to my early winter forecast released in July. It’s important to keep in mind that the winter forecast map is for a 3-month period (roughly between December 1st to February 28th). It’s difficult to capture the entire forecast and put it onto one map, which is why it is pivotal that you read the discussion for your region in the next section (each region is numbered on the map above). For example, I may be predicting a warm and dry winter for you as a whole but may be expecting one of the three months to be very wet and cool. That’s not going to be depicted on the map but will be in your regional discussion. PLEASE keep that in mind.

It seems that the month of December will be warmer than average for a large region of the U.S. (unless there is blocking over Greenland/Arctic), BUT that is still a bit of a wildcard as I stated earlier this year. I expect the eastern U.S. to transition into a colder pattern later in the winter, but that could occur earlier or later than I’m currently anticipating. There are always errors in timing every year. My goal is to capture the big picture in these seasonal forecasts and cover the explicit details later.

The best chances for California and surrounding regions across the West Coast to get rain/snow this winter will be in December, and those chances will be more prevalent across northern California and maybe a bit northward into parts of Washington and Oregon. However, I have really backed away from this winter being a significant drought-breaker for California due to the fact that it seems that ridging could try to re-establish itself later in the winter. I kept the Pacific Northwest as having another very dry and warm winter, despite December potentially being the exception to that, and I expanded the warm/dry category all the way down into much of California.

I still remain very bullish on this being a big winter from the Southern Plains to the Southeastern U.S. and into the Mid-Atlantic. There are likely going to be numerous systems moving across the Southern U.S. this winter that will bring several opportunities for snow and ice. December is still a wildcard month simply because the source of Arctic air may not be available, but as cold air becomes more readily available later on in the winter, the snow/ice chances should increase.

It could definitely be warm across the Northern Plains to the Great Lakes and into the Northeast early in the winter, but temperatures should really drop off from the Great Lakes into parts of the Northeast later in the winter. I went ahead and removed the eastward extent of the above-average temperatures that extended into the Great Lakes in my early winter forecast. The Northeast likely won’t be hit with nearly as much snow this winter as last year. Remember the insane amounts of snow Boston received? I doubt anything close to that will occur this winter for that region.

What To Expect For Your Area – A Region-By-Region Breakdown:

Region 1: The Pacific Northwest will likely once again have a warm and dry winter similar to the last two. However, December should bring numerous chances for rain and/or snow, making it initially seem that this winter will be different. While places like northern California could get beneficial moisture into the area early on, additional opportunities at receiving much needed precipitation will likely fade going into January and February, despite the strong El Niño that will still be in place.

Region 2: While most forecasts are calling for Southern California to receive copious amounts of rain this winter, my forecast calls for little drought relief, although there could be a few opportunities for some rainfall. Since it seems that ridging could try to re-establish itself later in January and February along the West Coast into Alaska, southern California may not receive the rain that typically occurs during an El Niño event. While El Niño will have a global impact on the weather this winter, it doesn’t guarantee certain conditions over a particular region. The sub-tropical jet stream will likely cut just a bit too far to the south, extending into parts of Mexico and into the Southeastern U.S. Unfortunately, that won’t help drought-stricken southern California. With all of this said, I have stated on numerous occasions that this is one part of this winter forecast that I am most uncertain about.

Region 3: Parts of the Central and Northern Plains may receive early snows from now going into December. The same goes for the Northern Rockies going into December, but once again, it will likely dry out and warm up as the winter progresses. Even in December, the Northern Plains could be unseasonably warm with above average warmth continuing through most of the winter. The exception to that will be possible in the far eastern extent of this region. Despite the chance at getting some early-season snowfall, most of this region will likely end up with below-average snowfall.

Region 4: Much of the Rockies have a good shot at receiving decent early-season snowfall that could continue through much of December. As the winter progresses, most of this area should warm up similar to the previous two winters, with much of the Rockies receiving lower snowfall amounts overall. The exception to this could be across the Southwest, where several systems could move through the area, possibly dumping heavy rain and snowfall amounts.

Region 5: If you’re located in this region, congrats! You’re in the in-between zone! On the map, I have average to above average temperatures/precipitation for this zone, but that’s only because this region will get a variety of weather that will cause everything to be about average over the 3-month period. While there won’t be as many systems moving across this region as there will be farther to the south, there will be a few opportunities for decent rain and/or snow, especially farther south. This could result in about average to even above average snowfall for parts of this region.

Region 6: This region has the highest chance of getting their coldest temperatures later in the winter. While the main storm track likely won’t be through this region this winter, there could be a few opportunities to have a few storm systems move in from the West Coast and cut northeast, impacting this area. The northern part of this zone will likely receive below-average snow, but across the Ohio Valley and Tennessee Valley, snowfall could be about average or even above average in places. However, overall precipitation amounts may end up being below-average across most of this area.

Region 7: Cities like Boston most likely will not get anywhere close to the snowfall amounts that fell last year, however there is a chance that a couple of fairly large systems could ride up the East Coast and impact the Northeast this winter. I put this region as having about average snowfall, but for the coastal regions, that’ll be contingent on a couple of larger systems impacting the region. I expect the worst of winter to be south of this region, but very cold air could inundate the region later in winter after a fairly warm start. The far northeastern areas in this zone will have the highest chance of having above-average temperatures throughout, but that is a bit of a wildcard at this point. Regions farther inland should expect about average snowfall with some locations even having below average snowfall.

Region 8: This will probably be the most active region this winter with many systems moving across the area. It’s important to note that every system won’t produce wintry precipitation, but this area will have plenty of snow and/or ice chances. A very active sub-tropical jet stream will pull moisture into the region, and with colder conditions expected especially later in the winter, this should allow for several winter weather potentials. It’s important to note that some of these events could be borderline rain/wintry weather events, making it important to watch the weather carefully this season. Ice storms could particularly be an issue across the southern parts of this region with above average snowfall likely across northern parts of this zone, roughly extending from the Appalachians into the Mid-Atlantic. Most of these systems will likely just shoot off the coast without pulling all the way up the East Coast. Determining the fine line between who gets more snow and who gets more ice this winter is a pretty difficult call at this point. Flooding could be an issue across this region this winter also.

Region 9: This region could be particularly wet this winter especially right along the Gulf Coast, making flooding more likely across some areas. Throughout the winter, there could be a variety of weather ranging from tornadoes/severe weather early in the winter to Arctic air masses pushing unusually far into the south later in the winter. It’s difficult to say just how far south the colder air will dig into this region, but it’s not out of the question for Florida to even experience a big freeze or two later in the winter. IF cold air is readily available during any of the heavy-precipitation events that are expected across this region this winter, some of the northern parts of this region could get some wintry precipitation later in the winter, but of course, that’s still a difficult call this early, given how unusual it is for most of these areas to get wintry precipitation.

Some Concluding Thoughts:

Again, December remains to be a wildcard and could be colder than anticipated for a larger area if blocking sets up over Greenland and the Arctic; however, this likely wouldn’t warrant any changes to the overall winter forecast if this occurs. Over the past two winters, I explained dozens of times why a negative NAO/AO (blocking high pressure over Greenland and the Arctic) was not necessary for colder temperatures in the central and eastern U.S. It turns out that was the case, and now there are entire research papers being written on this very topic. However, for December to be colder than expected, it would be a bit more dependent on having a negative NAO/AO, and I’ll explain the reasoning for that in my detailed analysis in a couple of weeks. The state of the NAO/AO may not be as big of a factor in January and February.

I realize that certain aspects of this winter forecast do not line up with many of the strong El Niño winters in the past that resulted in above-average temperatures for much of the U.S. While the impacts of this El Niño will be largely felt across parts of the U.S., I take into account other factors and often stay away from using terminology like “your typical El Niño winter.” A simple Google search will reveal to you that those kinds of forecasts are all over the internet this year, but keep in mind that it’s NEVER that easy in meteorology.

I will provide many updates on Firsthand Weather and on social media throughout this winter and will do my best to put out a forecast similar to this one each month. More times than not, a 3-month forecast, such as this one, does not necessarily depict each individual month too well. My goal will be to do that a bit better this winter by providing these monthly forecasts!