2014 Atlantic Hurricane Season Forecast

By: Bluestorm5 , 3:04 PM GMT on May 03, 2014

Share this Blog
14
+



INTRODUCTION

Hey, y'all! I hope the year of 2014 is off to a wonderful start for y'all. Well, we're now in the month of May which mean the traditional start of 2014 Atlantic hurricane season on June 1st is quickly approaching. The month of May is also the best time to release a yearly hurricane season forecast as well. I know some bloggers on Weather Underground like to release their forecast a little earlier on March or April, but I prefer to release my forecasts as close to deadline as possible because of accuracy. First of all, no one should ever depend heavily on seasonal hurricane forecasts as we all found out the hard way last year. 2013 hurricane season was expected by many to be an active one with the number of storms, hurricanes, and major hurricanes to be above normal. However, we ended up with 14 storms, 2 hurricanes, and 0 major hurricane (normal season is 12 storms, 6 hurricanes, and 3 major hurricanes). My forecast last year was 14-18 storms, 6-8 hurricanes, and 2-4 majors. Technically because I got the number of storms correct last year, I was one of 15 winners out of 142 WU bloggers for trHUrrIXC5MMX's (now MaxWeather) contest. Last year, I chose to go against the consensus and predicted a calmer season. Even so, my forecast still busted horribly like nearly every tropical meteorologists, WU bloggers, and weather geeks did. The bust was so bad that the infamous Colorado State University hurricane forecasting research team nearly ran out of funds for their wonderful project that had been going for around 30 years now. Seasonal hurricane forecasts are not perfect, but that's the beauty of science. Even if we know that the forecast isn't going to be great, at least we're still trying so we can learn something new so we can become better at forecasting. As for myself, I've gotten a lot more forecasting practice since the first day of college last August. I spent about hundred days total forecasting in WxChallenge for eleven cities around this country. I did very well, finishing ranked 208th in nation out of 2,000 forecasters while winning a trophy for the best 8 days forecast for Grand Forks, North Dakota among 500-750 freshmen & sophomores. I also finished 4th out of 25 UNCA forecasters for the year as well. Doing WxChallenge forecasts almost everyday in college definitely help me become a better forecaster as well as picking up more meteorology knowledge and what to expect from computer models as well as recognizing trends from them. I am confident that doing these forecasts will help me with hurricane season forecast as well. Now that I got higher confidence in my forecasting skills, I believe I can do much better with this year's forecast than the last several years combined. Now, it's time to discuss what to expect for 2014 hurricane season in Atlantic basin.

LOOKING AT OCEANIC AND ATMOSPHERIC PATTERNS

I don't think many people realize how global the effects of oceans are to our planet's atmosphere, especially when it comes to weather in United States of America. Atmospheric patterns for certain locations on this planet heavily depends on how much warmer (positive phase) or cooler (negative phase) the oceans are comparing to normal. Meteorologists call them climate oscillations. Like the activity of almost all weather in USA, the activity of an Atlantic hurricane season depends on what the conditions are like for oscillations in several places. For this forecast, we'll focus on three oscillations: El Nino-Southern Oscillation (ENSO or El Nino), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO). The most important one out of these three for Atlantic hurricane is the phase of El Nino-Southern Oscillation. During a year with positive ENSO phase (also known as El Nino event) when the water of equatorial Pacific is very warm, the air above the ocean will be warmer as well. Warm air over Pacific will rise up into the atmosphere because it's more dense than cold air. As result, we get more thunderstorms and the outflow from these storms will lead to higher wind shear across Gulf of Mexico, Caribbean Sea, and Cape Verde region of Atlantic Ocean. Higher wind shear is not healthy for tropical cyclones because it'll tilt the structure of the storm and kills it. Bottom line: El Nino events typically lead to less active than normal hurricane seasons in Atlantic Ocean. Now, it's time to discuss the current phase of El Nino-Southern Oscillation. It has been five years since we last got an El Nino event in Pacific heading into Atlantic hurricane season, the last one during the year of 2009. However, the end to the streak of non-El Nino years seem imminent heading into 2014 hurricane season. A strong westerly wind burst occurred over Pacific this past winter resulted in Kelvin wave been created in waters of Central Pacific. With an anomaly of 6° Celsius (Figure 1), this is the most impressive Kelvin wave ever observed. The anomaly of this current Kelvin wave is even warmer than the one in 1997 leading to "Super El Nino" event.



Figure 1: Climate Prediction Center's weekly ENSO update as of April 28, 2014

However, there was an episode of easterly winds during that temporarily stalled the eastward movement of Kelvin wave which lead to a stall in the warming of Pacific in ENSO region (Figure 2). Because of this, it's unlikely we'll see "super" El Nino similar to the one in 1997. However, westerly winds should resume at some point in May or June and this powerful Kelvin wave will move toward eastern equatorial Pacific. Once this wave start surfacing over there, El Nino event will start with a massive surface warming of equatorial Pacific that will release a lot of warm air into the atmosphere (Figure 3).



Figure 2: Official El Nino daily value from website TropicalTidbits run by WU blogger Levi Cowan. You can clearly see the stall during April.



Figure 3: Here's GIF of El Nino events of 80s and 90s from NOAA. Note how the warming started in eastern Pacific and spread out westward. If you can't get this GIF to work, just open this image in new tab and that should do the trick.

Now, let's move on to another oscillation: Pacific Decadal Oscillation (PDO). Why is this oscillation so critical to Atlantic hurricane season? Because having Pacific Decadal Oscillation in positive phase, when waters off coast of Alaska and British Columbia are warmer than usual, sometimes enhance El Nino to a stronger strength. PDO had been mostly negative since 2007, but it doesn't seem to be the case this year with all 3 months of 2014 showing positive number so far. In additional to that, there's a CFSv2 forecast (Figure 4) that shows PDO staying positive during this year's hurricane season as well as El Nino of at least moderate strength existing at the same time. Yet another oscillation to consider for 2014 Atlantic hurricanes season is Atlantic Multidecadal Oscillation (AMO). For most of the last 19 years since 1995, AMO had been positive resulting in few more active hurricane seasons than normal. While AMO is capable of staying positive for another few decades, it's undergoing a hiccup this year as it had turned negative in the past few months. It's negative because the water in Cape Verde region of Atlantic had turned colder than normal while subtropical waters off coast of New England region of United States of America had turned much warmer than normal (Figure 5). Waters between Canada and Europe is also much colder than normal which is yet another support why AMO is negative. Why is this so important? Because Cape Verde region is birthplace of some of the strongest and long-lasting hurricanes. Having cooler waters in that region reduce the chance of a formation of Cape Verde-type hurricane. Therefore, the number of storms, hurricanes, and majors get reduced in negative AMO years.



Figure 4: Here's the CFSv2 forecast from Climate Prediction Center for September 2014 to November 2014. Note how El Nino is at least of moderate strength while Pacific Decadal Oscillation (PDO) stay positive during this time period.



Figure 5: Sea surface anomaly from website TropicalTidbits run by WU blogger Levi Cowan.

In additional to oscillations, we could also look at Sahel region of Africa where tropical waves are produced every season. I've never thought about looking into the wetness or dryness of Sahel region determining Atlantic hurricane season until @webberweather pointed it out on Twitter back in March. The idea of using Sahel region to forecast the season: in a wet Sahel year, tropical waves are more powerful and this lead to more stronger storms for the season. Dry Sahel year, according to this theory, got an opposite effect. We have been in a period of dry Sahel region for a few decades now (Figure 6), but most of forecasts point to a wet Sahel region this time around for 2014 hurricane season which could promote at least some activity in Cape Verde region.



Figure 6: Most recent Sahel region rainfall graph from University of Washington/NOAA NCDC.

FORECASTING 2014 ATLANTIC HURRICANE SEASON

Now that I've explained current conditions of oscillations and planet's atmosphere, it's time to come up with a forecast. Obviously I want to have analogs that's the closest to this upcoming season so I got to start somewhere. Because of numerous of forecasts calling for at least moderate El Nino (value of 1.0+), I've decided to use all years since 1950 with El Nino having a value greater than 1.0. That'll give me 14 hurricane seasons to work with. In one of my atmospheric science classes this past spring semester, I found Excel to be extremely useful tool for number crunching so it's time to use my knowledge of that program for my hurricane forecast. For each of 14 hurricane seasons with at least moderate El Nino, I've added in how strong El Nino was, what was the phase of PDO and AMO that year, and whether if Sahel region was wet or not at the same time. Next, I did series of calculations using Excel to average out number of storms, hurricanes, and major hurricanes (Cat. 3 or stronger) for four different categories (strength of El Nino, phase of PDO, phase of AMO, and phase of Sahel). Now that I'm all set up with my large database, I know that this year could have a positive PDO, a negative AMO, and a wet Sahel region. Therefore, I used averages of these three categories and calculated them with averages of a moderate El Nino year, a strong El Nino year, or a super El Nino year. Based on my calculations, I came up with the average of 7.4666 storms, 3.7666 hurricanes, and 1.25833 majors if you combine all three final averages from each El Nino categories I've listed on Excel (Figure 7). It's worth noting that the average amount of storms decrease the stronger El Nino is, but it doesn't seem to affect number of hurricanes or major hurricanes.



Figure 7: Calculations that I did using an Excel spreadsheet. Database of 14 hurricane seasons with at least moderate El Nino strength included. Values of El Nino, PDO, and AMO are found using couple of sources linked. Sahel years are determined using a graph (Figure 6). Finally, calculations are done by me. Open the image in new tab for the absolute best quality.

Now I'm ready to release my forecast. The factors I looked at for this forecast included several forecasts that show this year will have at least moderate El Nino which could increase the wind shear across Atlantic basin effecting majority of Atlantic cyclones, a positive PDO possibly enhancing the strength of El Nino even farther, a negative AMO to reduce activity of Atlantic season thanks to cooler Cape Verde waters, a wet Sahel region to at least allow some stronger tropical waves to survive in Cape Verde region, weak vertical instability that should limit the strength of tropical cyclones in Atlantic, looking at analog years with at least moderate El Nino, and my Excel calculations above. Based on these numerous factors, here's my forecast for 2014 Atlantic hurricane season: 7-10 storms, 3-5 hurricanes, and 0-2 majors (Figure 8). Also based on these factors, I believe that most of activity for this year's hurricane season will be in subtropical region of Atlantic thanks to warmer than normal waters while Cape Verde region struggles due to higher shear from El Nino and cooler waters. Stronger tropical waves, thanks to wet Sahel region, should open up few windows in Cape Verde region, though. However, I am not expect for any storms to survive the infamous "Graveyard of Tropical Cyclones" of Eastern Caribbean Sea because almost none of them will be strong enough to handle higher shear that could be found in that area. While most of Gulf of Mexico should shut down due to higher shear from El Nino, northern half of the gulf could stay out of trouble and allow a strong storm or two to sneak into Southern USA (Figure 9).



Figure 8: My 2014 Atlantic hurricane season forecast.



Figure 9: My forecast of four regions where storms could peak in.

Just remember that seasonal hurricane forecasting is not a perfect science and these kind of forecasts shouldn't be taken seriously, especially my own forecast. Please pay attention to National Hurricane Center website once the season get rolling on June 1st. I wish y'all an another safe hurricane season and thank y'all for reading my long blog post. Feel free to leave any question, correction, or comment below :)

- Kyle Noël



the best web counter


Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 21 - 1

Page: 1 — Blog Index

21. WunderAlertBot (Admin)
8:39 PM GMT on May 06, 2014
Bluestorm5 has created a new entry.
20. nigel20
8:14 PM GMT on May 05, 2014
Lovely blog post, Kyle!
Member Since: November 6, 2010 Posts: 11 Comments: 8226
19. BaltimoreBrian
5:27 AM GMT on May 05, 2014
Quoting 14. Astrometeor:



Correction? As in grammar corrections? :D


Member Since: August 9, 2011 Posts: 26 Comments: 8630
18. MaxWeather
4:04 PM GMT on May 04, 2014
Hey Blue... I made a mistake with that number I gave ya n Ped... those (44-45) were already taken
New Ones...

You: #50
Pedley: #51
Member Since: April 11, 2014 Posts: 23 Comments: 1241
15. Bluestorm5
4:00 AM GMT on May 04, 2014
Quoting 12. sar2401:


You're welcome. I do things like that all the time. I still sometimes list California as my state of residence, and I haven't lived there for 9 years.

I was reading about wet vs dry Sahel thing again and thinking that the effect may have something to do with the amount of Saharan dust, with a dry year presumably producing more dust, thereby reducing instability in the MDR. Other than that, I can't imagine why storms would be very affected by a dry or wet Sahel. I also think SST's get too much attention. Once we reach a certain level of warmth, a little more doesn't really make much difference. We've seen this over and over again in the Gulf, when the basin was filled with the much vaunted "rocket fuel"...and nothing happened. Same thing has occurred in the Atlantic, with warmer than average SST's. Without some instability, it really doesn't matter how warm the water is - it won't create instability. The position of the A-B high is probably the single biggest factor in either allowing or killing instability in the Atlantic. In the face of a strong high, we get subsiding, dry air. That, along with the persistent high pressure, made it extremely difficult for lows to form, and for them to strengthen much when they do. I have no idea what causes the A-B high to move west and stay there for months. Hopefully someone smarter than me will figure that out one of these days. :-)


I'm no expert either. That's why I do these blogs so I can self-teach myself something new. My mom read this blog and thought it was UNCA education that made my blog so knowledgeable, but I told her that I self-taught 75% of what I know about hurricanes with 20% coming from guys on here. 5% is, of course, what I pick up in ATMS 103. Honestly, you might be right about SST, but these storms still need minimum warm water no matter what and I think we'll have a tough time having minimum warm source in Cape Verde region this year.

Quoting 13. Astrometeor:



I think that a wet Sahel means that the tropical waves will be healthier/stronger when they exit the African coastline than they would normally otherwise be.


That's what I'm led to believe.

Quoting 14. Astrometeor:



Correction? As in grammar corrections? :D


There's so many grammar mistakes in this one that you'll get tired of correcting me by the time you reach the part about PDO/El Nino forecast. Oh and don't take this as a challenge lol. I don't need grammatical correction :)
Member Since: August 1, 2011 Posts: 28 Comments: 8031
14. Astrometeor
3:45 AM GMT on May 04, 2014
Quoting Bluestorm5:
Feel free to leave any question, correction, or comment below :)


Correction? As in grammar corrections? :D
Member Since: July 2, 2012 Posts: 101 Comments: 10360
13. Astrometeor
3:43 AM GMT on May 04, 2014
Quoting sar2401:

You're welcome. I do things like that all the time. I still sometimes list California as my state of residence, and I haven't lived there for 9 years.

I was reading about wet vs dry Sahel thing again and thinking that the effect may have something to do with the amount of Saharan dust, with a dry year presumably producing more dust, thereby reducing instability in the MDR. Other than that, I can't imagine why storms would be very affected by a dry or wet Sahel. I also think SST's get too much attention. Once we reach a certain level of warmth, a little more doesn't really make much difference. We've seen this over and over again in the Gulf, when the basin was filled with the much vaunted "rocket fuel"...and nothing happened. Same thing has occurred in the Atlantic, with warmer than average SST's. Without some instability, it really doesn't matter how warm the water is - it won't create instability. The position of the A-B high is probably the single biggest factor in either allowing or killing instability in the Atlantic. In the face of a strong high, we get subsiding, dry air. That, along with the persistent high pressure, made it extremely difficult for lows to form, and for them to strengthen much when they do. I have no idea what causes the A-B high to move west and stay there for months. Hopefully someone smarter than me will figure that out one of these days. :-)


I think that a wet Sahel means that the tropical waves will be healthier/stronger when they exit the African coastline than they would normally otherwise be.
Member Since: July 2, 2012 Posts: 101 Comments: 10360
12. sar2401
3:11 AM GMT on May 04, 2014
Quoting 11. Bluestorm5:



That's what I get for typing at 2 in the morning :P Thanks!

You're welcome. I do things like that all the time. I still sometimes list California as my state of residence, and I haven't lived there for 9 years.

I was reading about wet vs dry Sahel thing again and thinking that the effect may have something to do with the amount of Saharan dust, with a dry year presumably producing more dust, thereby reducing instability in the MDR. Other than that, I can't imagine why storms would be very affected by a dry or wet Sahel. I also think SST's get too much attention. Once we reach a certain level of warmth, a little more doesn't really make much difference. We've seen this over and over again in the Gulf, when the basin was filled with the much vaunted "rocket fuel"...and nothing happened. Same thing has occurred in the Atlantic, with warmer than average SST's. Without some instability, it really doesn't matter how warm the water is - it won't create instability. The position of the A-B high is probably the single biggest factor in either allowing or killing instability in the Atlantic. In the face of a strong high, we get subsiding, dry air. That, along with the persistent high pressure, made it extremely difficult for lows to form, and for them to strengthen much when they do. I have no idea what causes the A-B high to move west and stay there for months. Hopefully someone smarter than me will figure that out one of these days. :-)
Member Since: October 2, 2004 Posts: 0 Comments: 16207
11. Bluestorm5
2:43 AM GMT on May 04, 2014
Quoting 9. sar2401:

Very nice work, Kyle. I know that took a lot of work. I suspect one of the majors will come out of the CV region and wander the Atlantic before it finally dies, but we shall see. IIRC, you won that contest for Grand Forks, North Dakota rather than Grand Forks, North Carolina, so you might want to change that. :-)


That's what I get for typing at 2 in the morning :P Thanks!
Member Since: August 1, 2011 Posts: 28 Comments: 8031
10. TylerStanfield
1:42 AM GMT on May 04, 2014
Excellent, well in-depth blog post! Great blog, Kyle!
I will be updating my February outlook of the 2014 hurricane season sometime tomorrow.
I actually believe that I may be upgrading my numbers.
Member Since: June 2, 2013 Posts: 8 Comments: 1347
9. sar2401
1:38 AM GMT on May 04, 2014
Very nice work, Kyle. I know that took a lot of work. I suspect one of the majors will come out of the CV region and wander the Atlantic before it finally dies, but we shall see. IIRC, you won that contest for Grand Forks, North Dakota rather than Grand Forks, North Carolina, so you might want to change that. :-)
Member Since: October 2, 2004 Posts: 0 Comments: 16207
8. MaxWeather
8:56 PM GMT on May 03, 2014
Very well Mr. Noel.
I like that overview of yours... 44th on my list

Hey Ped... I caught you too... 45th

I see several 9, 3, 1 forecasts in my list now...hmm
Member Since: April 11, 2014 Posts: 23 Comments: 1241
7. Bluestorm5
7:25 PM GMT on May 03, 2014
Quoting 6. GTstormChaserCaleb:

Great blog discussion, Bluestorm5 :) Are you anticipating an active Jet Stream in which we get a lot more frontal cyclogenesis (tropical transitions) as opposed tropical systems that originate from the deep tropics?
I haven't thought about that too much, but El Nino does usually produce stronger subtropical jet stream so I guess that support my reasoning why few storms could sneak up to us from Gulf of Mexico or just off coast of East Coast. We'll see :)
Member Since: August 1, 2011 Posts: 28 Comments: 8031
6. GTstormChaserCaleb
6:03 PM GMT on May 03, 2014
Great blog discussion, Bluestorm5 :) Are you anticipating an active Jet Stream in which we get a lot more frontal cyclogenesis (tropical transitions) as opposed tropical systems that originate from the deep tropics?
Member Since: June 30, 2013 Posts: 12 Comments: 8566
5. josF
5:26 PM GMT on May 03, 2014
Thank you,I enjoyed your thoughtful discussion.
Member Since: August 25, 2011 Posts: 0 Comments: 66
4. MAweatherboy1
4:19 PM GMT on May 03, 2014
Great discussion there Blue, very in-depth. We'll see how this year turns out!
Member Since: February 11, 2012 Posts: 83 Comments: 7844
3. Andrebrooks
3:49 PM GMT on May 03, 2014
We might get to Josephine.
Member Since: March 25, 2013 Posts: 30 Comments: 1184
2. PedleyCA
3:33 PM GMT on May 03, 2014
Nice analysis there. Time will tell, I got 9/3/1 for my picks this year. Good Luck with yours....
Member Since: February 29, 2012 Posts: 0 Comments: 5953
1. Tropicsweatherpr
3:19 PM GMT on May 03, 2014
Excellent discussion Kyle and I agree with your forecast. I shared it on Twitter.
Member Since: April 29, 2009 Posts: 75 Comments: 14407

Viewing: 21 - 1

Page: 1 — Blog Index

Top of Page

About Bluestorm5

19 year old freshman at UNC Asheville majoring in atmospheric sciences. I'm deaf and proud of it :) Twitter: @KyleNoel15

Local Weather

Mostly Cloudy
73 °F
Mostly Cloudy