How 2018’s Fall Foliage Season May Shake Out

It’s many people’s favorite time of the year: football season, crisp, cool nights, pumpkin patches, hay rides and of course fall foliage. Autumn can be spectacular around here, but the quality of the foliage season can vary from year to year.

WHAT MAKES FOR A GREAT FOLIAGE SEASON?

1) A WET EARLY GROWING SEASON

If dry conditions prevail in the spring and early summer, there is an increased risk of leaves dropping before they reach peak color in the fall. This year, we DID have a pretty wet period from April-June.

2) SUNNY DAYS AND CLEAR NIGHTS LATE IN SUMMER AND EARLY IN AUTUMN

Here’s where we may be in some trouble this year. September has been quite cloudy and wet across the area. In fact, it’s been the wettest September on record. 

3) CALM, SUNNY DAYS IN OCTOBER

What we don’t want in October is a bunch of rainy, windy days, especially later on the month. Those conditions will help pull down leaves and lead to a muted foliage season.  In the first half of the month, cool and dry days and nights would be ideal. Welp:

Early October is looking pretty warm overall.

SCIENCE OF FALL FOLIAGE

Why do leaves change color? It’s all about chlorophyll. That’s what gives leaves their green color. But leaves have other pigments as well and as daylight decreases in the fall, chlorophyll quickly depletes. This allows those other pigments such as yellow, red, orange, etc to show up.

CURRENT FOLIAGE STATUS

We are not seeing much color yet locally. Pockets here and there but overall it seems like we already running behind schedule a bit.

Colors are most noticeable in areas well north of us, mainly in the mountains.

Peak colors typically occur in mid-to-late October around here. Sometimes we see a peak around October 16-23, sometimes more like October 22-31. I suspect we’ll see the latter this year.

 

Some Very Early Thoughts On Winter 2018-2019

It’s still (astronomical) summer and it’s going to feel like it for the next handful of days with warm, humid weather in the forecast. It’s WAY too early to put out an official winter forecast. But I thought I’d share a few thoughts on the upcoming winter anyway. With the important caveat:

THIS IS NOT A FORECAST.

THE OFFICIAL WINTER FORECAST WILL BE ISSUED ON AIR AND ONLINE AROUND NOVEMBER 1

Ok, now that we have that out of the way. This post will not dive into ALL the factors that I surely will be looking at when I compile the forecast in 6 weeks. I’ll just touch on a couple here.

#1 The Winter Is Likely To Feature A Weak El Nino

Remember, El Nino is a phenomenon having to do with water temperatures in the Pacific Ocean and how they compare to average. El Nino is a warming of the waters in the eastern Pacific, near the equator. What does this have to do with our weather?? Well, the oceans and the atmosphere are one big system and what happens in the oceans can influence how the atmosphere behaves.

Right now odds favor an El Nino this winter although the odds of it being a “neutral” winter are not negligible (at 31%).  

The strength of an El Nino is important. Weak El Ninos tend to result in more “surprises” and more variance than strong ones. In other words, the range of outcomes is greater than during a winter featuring a strong El Nino.

The location of the warmest water (compared to average) is also important. A “standard” El Nino sees the warmest water banked up against South America. But there is a special flavor of El Nino called “modoki”, which sees the warmest water farther west.These 2 flavors of El Nino often produce winters over the US that are quiet different.   Odds favor a “modoki” this winter.

Modiki: 

#2 The “QBO” Or Quasi-biennial Oscillation Is Going From VERY Negative (Easterly) To Near Neutral

Say what? The QBO refers to the oscillation of river of air at very high altitudes in the atmosphere. It switches directions at regular intervals and has been shown to have an impact on weather patterns in the northern hemisphere winter.  It was very “negative” or easterly last winter through this summer but is trending back toward neutral.

Again, so what?

Winter Outlooks Are Largely Based On Looking At The Past

Making a seasonal forecast is tough but thankfully we have lots of data to look at., including detailed records of the past. So, we look for years with similar setups and see what happened. For the purposes of this post, I’ll just look at past years with weak modoki El Ninos and a QBO trend similar to this fall. When I do the “real” forecast, I will be looking at much more than this.

Temperatures (averaged together) during winters with weak modoki El Ninos:

Finding years with a weak modoki El Nino AND a QBO trending from very negative back toward neutral is tough. Only found a few. Average them and you get this:

Precipitation anomalies: 

Using these factors alone, the winter of 1968-1969 is the best overall match. Temperatures that winter:

Pretty cold winter. Snow was nothing to write home about. A bit below our average in the lower/mid 60s actually.

Again, the forecast will come out sometime around November 1. This just gave you a little peek behind the curtain. I love the challenge of the winter forecast and look forward to trying to beat the atmosphere this year!

 

 

 

August Outlook: Warm Like July But More Rain Than July

The final month of “meteorological” summer gets underway Wednesday. Before we get to the forecast for August, let’s quickly review July.

July started hotter than a firecracker. The heat was accompanied by some remarkably dry weather, too. Yards browned up in a hurry.

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July was the warmest since 2012 in Youngstown. Nowhere near the top of the record book but significant nonetheless. 2018-07-31_20-12-13

We were not alone. Many parts of the US had a warmer-than-average July. Temperature anomalies: prism_conus_tavg_anom_MTD

August will get underway with fairly seasonable weather through Friday. After that, we are going to get back into the kind of pattern that produced the hot weather in early July. The first half of August looks quite hot…the second half may feature more frequent cool shots. Overall, odds favor another warmer-than-average month. The highest departures from average should end up being in New England. CPC Monthly Temps

While a *WET* month does not seem likely, odds are favoring a month with more frequent rains than July. That, combined with the bouts of wet weather that we had in late July, means that we should avoid widespread drought conditions this summer. CPC Monthly Precip

By the way, August has been one of our more benign months in recent years, at least as far as temperatures go. 2016 was the exception; it was the 7th warmest August on record.  Otherwise, temperatures have been pretty close to the average (combining highs and lows) of 68.1. In fact, 2017 and 2013 were exactly average. august

Spring 2018 Forecast

It’s that time of the year. Everyone is anxious for warmer days, later sunsets and blooming flowers (maybe not the pollen though).  Patience is called for though…after all we live in NE Ohio and western Pennsylvania! Winter can overstay it’s welcome into March or even April some years. In fact, on average, 21% of our annual snow has yet to fall! 

That said, March 1st is the start of “meteorological” spring, which consists of the months of March, April and May. Meteorologists like tidy records and since the astronomical seasons don’t always begin and end on the same days every year, we made up our own seasons. That’s how we roll.

Average highs in spring:

One of the things we’ll be keeping an eye on as we get into spring is the severe drought across the middle of the country. If that area remains dry, it ups the odds of hot weather centering over the Plains states in spring and summer.  If that is the case, there could be implications downstream in out area. An increase in precipitation for Ohio and Pennsylvania is a possible outcome….as there is often an active storm track on the northern and eastern sides of a mid-continent heat ridge.

THE FORECAST 

Right now I think odds favor spring being near to somewhat warmer-than-average. I think the chances of a warm spring are higher than the chances for a chilly season. A somewhat wetter-than-average spring is also likely.

 

HOW’D THE WINTER FORECAST DO?

Our winter outlook was looking quite good until the very warm 2nd half of February. Here was the temperature forecast: 

Here’s what has actually happened:

Pretty decent, but I wouldn’t give it an “A”. The cold was centered farther west than the forecast as the ridge off the Southeast coast really fought back hard, especially late in the game.

Temperatures compared to average in Youngstown during winter:  

DECEMBER: -2.6°
JANUARY: -1.3°
FEBRUARY: +7.2° (4TH WARMEST ON RECORD)

I give our snow forecast an “incomplete” as we are not done with snow yet! The last flakes typically fly in early April.  As of February 28th, snow totals have been above-average. 

 

Updated Winter 2017-2018 Forecast

Welcome to (Meteorological) Winter! When I issued the Winter Forecast about a month ago I said I would do a full update on December 1 and so here we are.

The themes of the original forecast were:

  1. Colder than the last couple of winters but still near or perhaps even slightly warmer than average. 
  2. Near-average snowfall. 

While presenting the forecast on TV, online and during speaking engagements I mentioned that I was “daring” the atmosphere to be cold. What I meant by that:  there has been a fairly remarkable stretch of warm weather in our region since Autumn 2015. Colder-than-average months have been quite rare. Until the atmosphere “proves” it can get cold (relative to average) the smart money is on warmth, right? So my original forecast was not that cold, despite some data suggesting a cold winter was coming.

The atmosphere looks like it is going to take me up on that dare.

What Do We Know Now That We Didn’t A Month Ago??

I’ll start with La Nina. The premise of this being a winter featuring a “weak” La Nina was certainly known a month ago but the “configuration” of the La Nina has certainly become more obvious recently. What does that mean? Well not all La Ninas are created equally. The orientation of the coldest water (relative to average) is very important. When the coldest water is close to the coast of South America (“east-based”) the atmospheric response tends to be one that favors cold weather in the eastern United States. The cold air tends to be centered farther west in North America when the coldest water in the Pacific is farther west. Here’s a look at the current water temperature anomalies (the important region is circled): 

Notice the change in the water temperatures over the last week, which shows cooling of the water in the easternmost region: 

I think this ups the odds of cold weather in our region this winter.

What else has happened in the month since the original forecast was issued? COLD weather in western and central Canada…especially when compared to last November. Check out the difference. 2016: 

2017: 

This has resulted in a good snowpack across that region and that can help “refrigerate” arctic air masses coming southward across that snowpack.

Remember that QBO thing I mentioned in my original forecast?

We have another month of QBO data under our belt now and it’s firmly in the “sweet spot” for cold weather in the East, especially when paired with a weak, east-based La Nina.

Ok So What’s The Forecast

Let’s look at this month-by-month.

Old December forecast: 

New December forecast (this is the biggest change in the forecast. December will likely be the coldest since 2010 here.): 

Old January: 

New January: 

Old February: 

New February: 

Old Winter (December-February) Forecast: 

New Winter Forecast: 

I have NOT changed the snowfall forecast. This winter may be colder than I originally thought but that does not necessarily mean snowier.

Forecast confidence has gone up since a month ago. I had temperatures in the “low” category then and for good reason.

The bottom line: I am now expecting a significantly colder winter than the last two and this winter can be more like the rather harsh seasons we had in 2013-2014 and 2014-2015. That is not to say it won’t occasionally get mild.  It will! A “January Thaw” is a distinct possibility.

Thanks for reading! Look for a video version of this forecast this evening!

 

Winter 2017-2018 Forecast

Time once again for my annual Winter Forecast. Please feel free to watch either the short version that aired on 21 News

http://www.wfmj.com/clip/13870419/erics-annual-winter-forecast-short-version

Or the long, much more detailed version:

Before we get to the forecast, let’s do a quick recap of recent winter weather across our region. It many be surprising to some that last winter will go into the record books as fairly snowy! 69″ at the Youngstown-Warren airport is a few inches ABOVE average. Temperatures? No surprise there…it was our 2nd consecutive mild winter.

Some highlights of last winter. How did we pick up that much snow when January and February were so balmy? December and March were quite a bit snowier-than-average:

4 of the last 5 winters have been fairly “extreme” temperature-wise. 2011-2012 was quite mild; 2013-2014 and 2014-2015 were harsh and 2015-2016, 2016-2017 were quite mild.

In the snow department, most winters have been snowier-than-average since the early 2000s. Last winter was a bit above average but the previous season was way below-average.

How do we make these forecasts? 

Seasonal forecasts are much different than your standard 7-day forecast you see on TV or get on a mobile app. I can’t tell you if it will snow on January 23rd or be mild on December 17th. Seasonal forecasts deal with broad patterns, both over the United States and globally. Forecasters look at what’s going on with water temperatures in the oceans, what winds in the stratosphere are doing, what the rate of increasing snow cover over Siberia is and much more.  We truly look globally. After assessing these things, we look back at previous years that had similar conditions. These are called “analogs”.  We determine what type of winter season unfolded in those years under those conditions and then see how likely it is that this winter will play out in a similar fashion.

Additionally, we have climate models that provide temperature and precipitation forecasts over several months. These models, just like the models we use to help us make a 7-day forecast, have their strengths and weaknesses and the forecaster must know how to use them correctly. Think of a weather computer model like a hammer. It’s a tool that requires a qualified human to use it correctly. The hammer will not build a house on it’s own and is also fairly useless in the hands of someone who isn’t skilled at using it.

Lastly, experience and intuition. Learning from past mistakes is very important in all walks of life and that includes weather forecasting…whether it’s a 3-hour forecast or a 3-month forecast.

La Nina

La Nina! What is it? Put simply, it’s the cooling of the waters in the equatorial Pacific Ocean, near South America. Why do we care about that?? What does it have to do with our weather in Ohio and Pennsylvania?

The oceans and atmosphere play in the same sandbox known as our planet. The atmosphere can react to changes in the ocean (and vice versa). Whenever this part of the Pacific cools (or warms, the “El Nino” phase) the steering currents in the atmosphere, or jet stream, can be altered. Often (but not always!) La Nina results in a stormy pattern over the Pacific Northwest and the Ohio Valley during the cold season. The stronger the La Nina (or El Nino), the more pronounced (and easier to predict) the affects typically are over the United States.

Current water temperature anomalies: 

We also take note of pools of cool and warm water in other places, such as near Australia, the northern Pacific and near the east and west coasts of the United States.

The QBO

The what? The quasi-biennial oscillation is important and the fact that it did not behave as expected likely contributed largely to last winter’s warmth (and so-so forecasts). Have a look:

This Year’s Analogs

There are other years I could include in this list but these are probably the best matches. What do they have in common? They were weak La Nina years and most were years with an easterly, or negative QBO. Most of these years did NOT have a warm November preceding winter, which we expect this year. (the exception? LAST November, which was warm. That’s part of the reason last year is on the list despite having an opposite QBO signal)

Notice most of the years on this list were modestly cold. Most had near to somewhat below average snow. Snow data for 1996-1997 is unavailable.

When we throw all these years in the hopper and create an average, here’s what the national temperature map looks like:

The Models

So based on the chilly-looking analogs, we should predict a slightly colder-than-average winter right?? Not so fast.  Much of the modeling shows a warm winter. Now, I believe the modeling is too warm….but it can’t be completely ignored. Here’s generally what the models are showing:

My forecast is, generally speaking a blend of the models and analogs, with more weight on the analogs. More on the forecast below.

Monthly Temperatures

I foresee a somewhat mild start to winter followed by more frequent arctic blasts in January. There will be loads of cold air in western and northern Canada to tap so any arctic intrusions, even if they are brief, could be powerful (even in a mild overall December).

February could bring a less cold pattern and may shake out near average.

Here’s the map for the whole season. I’m expecting a 3-month departure from average of 0 to +2 degrees. 

Snow Forecast 

While I do expect PRECIPITATION to be above average this winter, SNOW should be pretty close to average. I expect a fair amount of “slop storms” that include chilly rains and mixed precipitation, especially in December.

It’s possible that March could be snowier-than-average again. But generally speaking I expect the snow to be divided up pretty close to climtalogical averages:

The Bottom Line 

A winter that is not as mild as the last two but not as cold as 2013-2014 and 2014-2015. My confidence is higher than last year because of a somewhat stronger La Nina signal and a more “well behaved” QBO. Temperatures are tricky. More on that below.

Impacts

Higher energy consumption this year.

What Could Go Wrong??

My confidence in the winter forecast is higher than last year but is not as high as two years ago when we have a raging El Nino. La Nina is still weak enough that other oscillations and factors can override it and dominate the pattern for stretches. These things are hard to predict more than a few weeks out.

The models could be full of baloney with their warm look. The atmosphere seems to “want” to be warm over our region (this has been the case for 2+ years) and so it’s hard to dismiss how warm the modeling is at this point.

On the flip side, if the warm November that we expect is a harbinger of the winter pattern (like last year) then my forecast is not warm enough.

Basically it comes down to this: My forecast is kind of in the middle of the warm models and cold-ish analogs. We should know more in a month, which is why:

I’ll have a full update December 1!

Blog: Summer 2017 Forecast

Astronomical Summer doesn’t begin for a few more weeks, but in meteorological circles, we define seasons a bit differently. Partly because we like nice, tidy records. The astronomical seasons do not begin and end on exactly the same dates every year so that “muddies” the records for those seasons slightly. Meteorological seasons begin and end on the same dates every year.

Meteorological Summer is, of course, June, July and August. The average highs for our region:

 

One of the things most people like about Summer, especially early Summer? The long days. We’ve come a longggg way since the dark days of Winter:

Over the last 20 years, we have had hot Summers, dry ones, cool ones and wet ones. Last year? Very warm and fairly wet (especially in July and August. June was drier-than-average).

Notice that the last 5 Summers have been wetter-than-average.

THE FORECAST

The season will start on a very cool note, especially in the first week of June. While temperatures will moderate as we head toward mid-month, odds still favor June 2017 shaking out as a cool one compared to average.

Will the whole season be this way? Unlikely. A somewhat warmer-than-average July and August should tilt the season into the “warm” category for eastern Ohio and western PA. Just NOT as warm as last year.

Seasonal precipitation forecasts are TOUGH. Especially in the warm season where one or two big thunderstorm days can really skew the numbers. “Persistence” forecasting methods would suggest that we just keep predicting wet Summers until the atmosphere proves it can produce a dry one. We’ve had 5 in a row.  That said, I don’t see anything in the data that gives me a high degree of confidence so for now we’ll call for an “average” season in the rain department.

 

BLOG: IS WINTER OVER? (DID IT BEGIN?)

I am frequently asked “what happened to the winters we USED to have?”, “where is all the snow”, “are we ever going to get a BIG storm?” etc. These are good questions and important ones. The atmosphere is extremely complicated and SIMPLE answers are often hard to come by.

I have spent a considerable amount of time this winter debunking the myth that winters were much colder and snowier in the 70s and 80s. They simply were not…in fact the 2010s have been the SNOWIEST decade (so far) since at least the 1960s. We also had back-to-back harsh winters, the likes we have not seen since the late 70s, just 2 and 3 years ago. Our memories can be quite short (on any number of subjects!) and weather is no exception.

The maps tell the story: here are the temperatures (compared to average) through February 13 in 2014: conus_ytd_t2avg_anom_2014.png

2015: conus_ytd_t2avg_anom_2015.png

And this year: conus_ytd_t2avg_anom_2017.png

The contrast is pretty remarkable.

One of the hallmarks of this winter season (and last year too) has been the lack of SUSTAINED cold. It gets cold for a couple or few days, but then it just gets mild again.

highsunder25.png

There really has just been one cold “snap” this season, early in January and it lasted 4 days. Notice all the cold snaps in the winters of 2013-2014 and 2014-2015.

WHY??

The reasons for the balmy winter weather are complicated. It’s easy to just be flippant and say “GLOBAL WARMING!!!!!”. I hear that a lot. The climate IS changing, but attributing individual weather events and even warm spells on the scale of months directly to climate change is unwise.

The simplest explanation for our mild winter lies over the Pacific ocean. A very strong jet stream, perhaps being aided by something called the Quasi-biennial oscillation (which has been record strong lately) has been unrelenting in recent months. The result has been a VERY wet winter in California and the West Coast. pacjet.png

Another result? Mild air floods the eastern 2/3 of the country. This Pacific jet acts as a real barrier for arctic air trying to come south in eastern North America. This “top down” view, looking over the North Pole, shows the west-to-east upper-air flow over North America. The cold stays “locked up” near the pole and/or gets shoved into Asia. poledown.png

THE REST OF WINTER

I see very few signs that this overall pattern will change for the rest of the season. Will it snow? Yes. Will it get cold occasionally? Yes. Like….in less than 24 hours! Wind chills by Thursday will be mainly in the single digits and teens: chillsthursam

There can be a couple of inches of snow in our northern viewing area, especially in Mercer County, Wednesday into Thursday. hiresp_snow_cleveland_61.png

But that’s gonna be it for snow for a while. A VERY balmy pattern will take over this weekend into next week. A high near 60 can occur for at least a few days: KYNG_2017021400_eps_min_max_15.png

The long-range modeling shows the same kind of pattern that we have been in all winter. Warm overall with brief periods of cold. The latest European model temperatures for the next month: eps_t2m_768h_conus_129.png

The American CFS model for March (average of last 14 runs): cfs_anom_t2m_noram_201703_56.png

Looks familiar.

Summer 2016 Review!

As you may know, meteorologists like to look at the seasons a little differently than others. Since the “astronomical” seasons do not start and end on the same dates every year, we use “meteorological” seasons for the purpose of tidy record-keeping. There is also climatology to consider; the meteorological seasons line up nicely with the 3 hottest/coolest months of the year. So, “meteorological summer” is June, July and August.

Under that premise, let’s do a quick review of summer 2016.

You may remember that we issued a summer forecast around Memorial Day. Have a look at it here.  

That forecast called for the warmest summer since 2012, with a near-average amount of 90-degree days. It worked out pretty well! We are at 6 90+ days so far and I think there is a chance we squeeze out 1 or 2 more next week.

Summer forecast:

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Here’s what happened:

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Not bad. The core of the warmth was centered over our region and not New England but overall I would give this forecast, not only for us but the whole lower 48, an A-/B+.

How did 2016 compare to recent history? It ended up being our hottest since 1995:

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August was particularly hot….the 6th warmest on record in Youngstown.

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On the precipitation-side, the summer of 2016 is an interesting one as well. Of course most had brown lawns for a good chunk of the season. The season will have a reputation as a dry one. Buttttt, the “official” numbers will tell a different story. Would you believe that summer 2016 will go in the record books as WETTER than average in Youngstown?? The airport (where the official observations are) logged a little over 13″ of rain, compared to the historical average, roughly 11.5″. It was our 5th consecutive wetter-than-average summer.

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But the airport was practically the wettest spot in our viewing area. Look at the rain anomalies and notice how the airport location stands out. Other areas were MUCH drier.

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We did make up some ground in August, especially north of 224.

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So Meteorological Fall is here. A transitional season in which we lose daylight rapidly and average high (and low) temperatures plummet quickly, especially during the second half of the season.

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We are expecting a warmer-than-average September. The season as a whole? Mild and probably on the dry side.