2 Weeks Away: What Are Chances For White Christmas This Year?

We are two weeks away from Christmas! Close enough now that we can take an educated guess at the chances for a “white” Christmas this year.

What’s a “White” Christmas?

No doubt there are varying definitions of a White Christmas throughout the country and throughout the world. A White Christmas in Atlanta might be thought of as someone seeing one snowflake on their windshield. We are heartier folk up here and our standards are a little higher! The definition of a “White Christmas” that we will use is:

1 INCH OF SNOW ON THE GROUND

Seeing snow falling on Christmas is not that uncommon around here in fact we see that on roughly 7 out of 10 Christmases. 1 inch of snow on the ground is less common but still almost happens half the time:

Of course the higher odds of having that much snow on the ground on December 25 are higher in the primary snowbelts of Ohio, Pennsylvania and New York.

What About This Year?

The pattern in the 5-7 days leading up to Christmas does not look WARM per se. We are unlikely to have a stretch with highs in the 60s. But, it does not look very cold either. The Lower 48 States as a whole will see a pattern dominated by Pacific air , not arctic air. This pattern will have a hard time generating a lot of opportunities for “pure” snow events. In other words, a pattern like this often is characterized by either 1) just rain events or 2) “slop” storms that bring some snow but also some rain and mixed precipitation.

So with that being the premise, I can’t forecast an above-average chance for a White Christmas this year. 2 weeks out, will go with about a 30% chance. We’ll of course spend a lot of time fine-tuning this forecast as we get closer. Stay tuned!

2019-2020 Winter Forecast

The LONG(LONG!) video version is here and/or you can check out the written version below. Leave a comment! Do you like the forecast??

It’s time once again for my annual winter forecast. It’s reasonable to ask: how good are these forecasts? Can you really do this?

The answer is YES. There is skill in these predictions. Is the skill as high as your typical 7-day forecast? No way. But there is a lot more skill in seasonal predictions than a total guess. This isn’t throwing darts. A good seasonal outlook has lots and lots of science behind it.

That being said, a case can be made that these outlooks are getting somewhat MORE difficult, despite advances in technology and knowledge. Why is that? Well a large part of creating a seasonal forecast is the reliance on “analogs”: years in which conditions in the atmosphere and oceans are similar to the current year. With the global climate (including ocean temperatures) warming so rapidly, looking at analog years before the 1990s or 2000s may be becoming impractical. The atmosphere was much different 40+ years ago.

LAST WINTER REVIEW

Last winter was a pretty uneventful one overall. December 2018 was mild and featured little snow. January was pretty by-the-books in terms of temperatures and snowfall, with one harsh cold snap at the end of the month. February turned quite mild (as it’s been prone to do in recent years).

We have reeled off 4 consecutive mild winters after back-to-back harsh ones in 2013-2014 and 2014-2015.

2019-2020 WINTER FACTORS

One of the first things we look at when making a winter forecast is: what’s the state of the water temperatures of the equatorial Pacific. This is where we look for El Nino (warm water) and La Nina (cold water). These water temperature anomalies can have a big impact on weather patterns in the northern hemisphere. This year things are looking pretty “neutral”, in other words there’s not much going on in this part of the ocean. A very weak El Nino may be brewing but La Nina is off the table. The most likely phase for the winter is “neutral”.

Another important area to look at is the northern Pacific, where there is a lot of warm water right now. This can encourage a ridge of high pressure to park over that region, which has implications for North America.

It was a wet summer in the Plains and a dry one in the Southeast. So? Well soil moisture can be an important factor when determining where ridges and troughs like to set up as we get into winter. Ridges of high pressure tend to want to hang out over dry areas. The opposite is true for troughs of low pressure.

It can be useful to know what the condition of the sun is. HOT right? Well for the purposes of the forecast, we want to know if the sun is “quiet” (few sunspots) or “active” (lots of sunspots). Why? Recent research shows that a quiet sun can help to encourage blocking patterns in parts of the northern hemisphere during winter. Blocking patterns can result in “stuck” weather patterns where dry/warm regimes and stormy/cold regimes don’t want to break. We are in a solar “minimum” now and likely will be for a few years.

The snow season is off to a fast start across parts of Canada. A deep, well-established snow pack can act as a refrigerant for arctic air masses descending from the high latitudes. Essentially, already cold air masses can be further cooled by traversing a snow-covered landscape.

LET’S GET TO THE FORECAST

Ok, I have gone over SOME of the things that are important pieces to this year’s forecast puzzle. There are many more but I don’t want everyone’s eyes to glaze over. Let’s get to the forecast.

My list of top analogs this year:

A lot of cold winters on that list. A couple of snowy winters and some not-so-snowy ones too. Overall I think 2004-2005 is the best match for this year.

Based on analog and computer model data, here’s the forecast. A wetter-than-average winter in our region:

The temperature forecast features warm weather in the West and the Southeast. Highest chances for a colder-than-average winter will be across the northern Great Lakes and parts of New England. I lean toward an average to perhaps slightly colder-than-average season here.

Given the analogs, this may be a conservative temperature forecast. Why is my forecast not colder? First of all, I really like 2004-2005 as an analog and that was a pretty average winter temperature-wise. Secondly, weak El Nino or neutral winters tend to trend toward recent climatology. What do I mean? Without a strong Nino/Nina signal, a good place to start when making the forecast is averaging together the last handful of winters. Here’s what that map looks like:

In addition, the atmosphere seems to “want” to be warm over our area. March is the only month that has been colder-than-average in 2019 (November should be month #2). 2018 only had 3 cooler-than-average months. You’d have lost a lot of money betting on cold over the last couple of years. Maybe the next few months will be different but until proven otherwise, I’m very hesitant to predict much unusual cold.

Snowfall is likely to be the biggest change from last year. I expect us to see a much snowier winter, with most places averaging 10-20% more snow than average.

Another way to compare last winter and this winter is like this:

IMPACTS

Expect higher energy bills this winter when compared to last, although again I do not think it will be a harsh winter. Salt usage will be higher with more snow on the way. As there are every winter, of course there will be occasional school adjustments.

A FORECAST UPDATE IS COMING IN EARLY DECEMBER

Very Cold November Pattern With Snow Chances Too

It was not that long ago that we were talking about endless summer…highs in the 80s were common early in October and air conditioners were still humming. November is getting underway with a much different flavor. Let’s touch on some specifics.

THURSDAY’S SNOW CHANCE

A cold front will cross the area Thursday morning and the temperature is expected to drop some throughout the day. Meanwhile, some moisture will “overrun” that front, leading to rising air and precipitation. It will take a while for the air up above our heads to cool sufficiently for snow production. That should occur at some point in the afternoon or evening. A changeover to wet snow will occur but honestly I don’t think we are in for much accumulation around here. The best moisture will be leaving us by the time it finally gets cold enough.

Simulated radar for the next few days:

Lake-effect flurries and snow showers will fly for a while into Friday morning. Local lake-effect accumulations will not be anything significant. Maybe an extra coating to an inch in northern Trumbull/Mercer.

Odds of 1” or more of snow Thursday into Thursday night (legend in lower left):

Odds of 2” or more:

National Weather Service snow forecast through 7am Friday:

THE NEXT COLD SHOT

The arctic front that will cross The Valley Sunday/Sunday night is very impressive-looking for this time of year. It will usher in some serious cold for at least the first half of next week. It’s November so the Great Lakes are still quite mild compared to the air that will be blowing over them so lake-effect should be plentiful next week in the usual favored areas. Wintry-looking weather map next Tuesday:

Water temperatures on Lake Erie are running above-average by a few degrees.

THIS COLD SNAP HAS SOME LEGS!

Waves of cold will plunge south over the next 10 days to 2 weeks. If this were January we’d be talking about several subzero temperatures and nasty wind chills.

DOES THIS MEAN ANYTHING FOR WINTER?

It seems quite likely that, compared to average, November will be the coldest month of 2019. Only one month has been colder-than-average this year (March). Actually, for as much warming as our area has seen in recent years, we have had a fair amount of cold Novembers this decade. The last 3 have been cold and 6 of the last 8 have been below the average (black line).

Does a cold November correlate to a cold winter?? Well, as with many things weather…the answer is complicated. More often than not, yes, a VERY cold November is followed by a colder-than-average winter. Here’s a composite of the winters that followed our top 10 coldest Novembers:

However, November 2018 was the 7th coldest November on record and the winter that followed was….ho hum. Mild December, typical January and warm February here.

WINTER FORECAST SOON!

May annual winter forecast will debut on 21 News at 6pm Thursday, with an encore at 11pm. Plus the long, geeks, detailed version will be posted online. More of a reader? I’ll have a written blog post (much like this one) here as well.

The Heat Is About To Break. Now What? A Few October Thoughts

Thursday will be the last hurrah for “Endless Summer”. Some places are likely to see mid 80s for the last time until next spring/summer. Warmest temperatures Thursday will be in Columbiana County.

The air mass change from Thursday to Friday will be dramatic. Temperatures will be 25-30 degrees cooler with a big reduction in dewpoints. We’ll go from blasting the A/C in some places Thursday to perhaps needing to kick on the furnace late Friday night/early Saturday.

The second week of October is likely to feature a back-and-forth pattern with some cool days balanced out by some milder days. Notice the orange (mild) air masses dance with the blue (cooler) air masses in this animation:

At the end of that animation, you can see that much of the country looks pretty mild. The second half of the month does not look all that cool (compared to average) and October is likely to come out in the wash warmer-than-average.

ARE WE DONE WITH “HOT” WEATHER?

After Thursday, yes I think we are done with temperatures in the mid/upper 80s with crazy high humidity. I don’t want to rule out a day here and there that brings temperatures into the mid/upper 70s but they will be much less common than they have been.

WHAT ABOUT WINTER??

One season at a time, haha. My annual winter forecast will debut on Thursday, November 7. The “short version” will be on 21 News at 6&11 while the long, detailed, “geeky” version (both video and in blog form) will be posted online.

Some Perspective On Next Week's Late-Season Heat Wave

More than likely you are aware that we have some unusual late-season heat coming our way early next week as September ends and October gets underway. But HOW unusual will this be? I thought I’d offer a few thoughts and stats on that subject.

THE SETUP

The pattern across North America will become highly amplified over the weekend early next week, as a strong trough of low pressure digs across the West. This will cause a huge, anomalous ridge of high pressure to pop across the East. If this were July, triple-digit heat would be common under the ridge and we’d probably be looking at mid 90s around here. It’s not midsummer anymore so temperatures can only get SO warm….but we’ll still see readings as much as 20-24 degrees warmer-than-average.

HOW HOT?

I think we have a legitimate chance of seeing 90 degrees on Tuesday, the first day of October. This would not only be a record high for that date, but an ALL_TIME record high for October. In recorded history, our area has not seen 90° after September 29.

The average date of the last 90 of the year? In the middle of August!

Tuesday is the day in which 90 is most likely, but Monday and Wednesday will also be very warm/hot.

WARM SEPTEMBERS VERY COMMON LATELY

Over the last 30 years, September has actually seen the LEAST amount of warming compared to every other month. BUT, the last 5 years have been a different story. 2015 didn’t crack the top 10 but it was the 13th warmest. September 2019 will finish in the top 10 and perhaps even top 5.

CLIMATE CHANGE LINK?

No single weather event or weather pattern can be directly attributed to climate change, especially while it is happening. Peer-reviewed study is needed and that takes time. That said, the rapidly warming atmosphere (and oceans) greatly increases the odds of extreme weather. The analogy I like to use is this: in the steroid era of baseball, every home run that was hit by Sammy Sosa, Barry Bonds, etc did not occur simply because they were using steroids. Many of those home runs would have occurred anyway. But the fact that they were using performance-enhancing drugs increased the odds that any given pitch would result in a home run.

Right now the planet “is on steroids” and so the odds of extreme weather patterns occurring is higher.

By the way, the oceans are absorbing a large portion of the heat. They are warming at an alarming rate and it IS impacting weather patterns. The oceans cannot sustain this and eventually the warming of the atmosphere is likely to make a significant jump upwards.

An alarming new report came out this week. It’s worth a read: https://www.nbcnews.com/news/world/cut-emissions-avert-catastrophic-sea-level-rise-u-n-study-n1058466

WHEN CAN I TURN INTO AUTUMN MAN/WOMAN?

The heat wave will break during the second half of next week and it’ll feel LIKE FALL next weekend. Probably some highs in the 60s and lows in the 40s. Not crazy cold…in fact just back to normal but it’ll finally feel crisp and cool for a while.

DOES THIS MEAN ANYTHING FOR WINTER?

Nah, not really. Late summer/early fall weather patterns generally do not have a strong correlation to wintertime regimes. Stay tuned for my annual winter forecast in late October/early November.

Previewing This Year's Fall Foliage Season

While many wish summer would continue indefinitely, in eastern Ohio and western Pennsylvania we live in a 4 season climate. There are many things about autumn that are great and of course the annual changing of the leaves is high on the list. We are lucky to have so many great spots (such as Mill Creek Park) to take in the show.

In 2018, a very warm and wet September and a toasty start to October kind of doomed the foliage season. We were not alone in seeing “forever summer”; here’s last September temperature anomalies:

September 2018 Temperatures

Many leaves simply turned brown and fell. The “peak” wasn’t much of one and it was very late…close to Halloween.

Our “typical” peak is somewhere between October 15-25.

WHAT ABOUT THIS YEAR

September is off to a very warm start again this year. And once again, we are not alone:

But, at least in parts of the area, it has not been as wet this September. Some places, mainly south of 224 are quite dry. It’s been wetter in much of Trumbull and Mercer counties during the second half of summer.

September 1-17 Rain

So it hasn’t been as wet as last September and that is a positive for the potential of a vivid show this year. BUT, much like last year the very warm pattern is likely to continue into late September and early October. Some of the long-range modeling is very toasty looking through the first half of October.

Long-range European model

So, while the generally drier weather should help, I’m concerned about the late-season warmth short-circuiting the fall colors again this year. It should be better than 2018 but likely not as good as some of our better years.

Why do the leaves change color? As the days get shorter, chlorophyll is depleted, allowing other pigments (instead of green) to come out of hiding.

Autumn officially gets underway very early in the day Monday.

Quick Summer 2019 Review

Summer 2019: A Warm, Stormy One

Summer (June-August) will go into the record books as a warm one with all 3 months ending up warmer-than average. July was the hottest vs. average. June of course was very wet. July and August brought less rain although we still had frequent storms and bouts of heavy rain, especially in Trumbull and Mercer counties. It was the wettest summer since 2003 and the 6th wettest on record.