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2007 typhoon season forecast

By: Dr. Jeff Masters, 1:51 PM GMT on May 21, 2007

It's going to be a below-average typhoon season in the Western Pacific, according to the April 23, 2007 forecast issued by Dr. Johnny Chan of the City University of Hong Hong. Dr. Chan is calling for 25 named storms and 14 typhoons in 2007, slightly below the average of 27 named storms and 17 typhoons. The forecast for a below-average typhoon season was based on three main factors:

1) The Western Pacific has been in an inactive period since 1998, and this inactivity is expected to persist.

2) This year should have neutral El Nio conditions, or a La Nia event. These conditions have led to below-average typhoon activity since the current inactive typhoon period began in 1998 (Figure 1).

3) A stronger-than-normal high pressure system has been in place over the subtropics in the Western Pacific in February and March of 2007. Such higher pressures are associated with reduced typhoon activity later in the year.

Figure 1. Time series of the annual number of named tropical storms in the Western Pacific. Red circles and blue squares indicate El Nio and La Nia years, respectively. The green triangle is this year's forecast. An average year has 27 named storms. Image credit: City University of Hong Kong.

How good are these forecasts?
Dr. Chan has been making seasonal typhoon forecasts since 2000, and his forecasts have been skillful. The 2000-2006 forecasts issued in April for number of named storms and typhoons have a Mean Square Skill Score of about 30 and 50, respectively, according to some quick calculations I did. This is considerably higher than the late May seasonal forecasts for Atlantic hurricane activity issued by both Dr. Bill Gray/Phil Klotzbach's team at Colorado State University and Tropical Storm Risk, Inc. However, hurricane activity in the Atlantic has varied much more from year-to-year in the past decade than typhoon activity in the Western Pacific. This makes the Atlantic forecast problem more challenging.

Typhoon Yutu
Typhoon Yutu, the season's first major typhoon, intensified to a Category 4 storm with 145 mph winds yesterday. The typhoon is over open water and weakening, but could pass through the islands near Iwo Jima as a Category 2 typhoon on Tuesday. Yutu is the second named storm of the year in the Western Pacific, which usually sees three named storms by the end of May.

Figure 2. Typhoon Yutu at 00 GMT May 20, 2007. Image credit: Navy/NRL.

Tuesday (tomorrow), I'll report on NOAA's 2007 Atlantic hurricane season forecast, which will be released at 11am EDT.

Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

TCW. That trough can be our friend in about a month. Almost looks like last years pattern. Hmmm... Right now conditions are terrible everywhere except that little spot way down in the SW Caribbean:) Thats it.
Avila is really been at forcasting for almost 30 years with his days back forcasting in cuba.He's a great guy and enjoy reading his discussion.He's great with models.

I remember speaking to him last season when formosa took me threw a tour.
03 i dont see this seasons pattern anything like 06 its actually got some similarities to 05.We'll see how evolves in the coming months.
Alittle bit. Really cant make that assumption at the end of May. Thats what screwed some forecasts up last season:) But hey, we may have a slow start then ramp up towards the end. Alot of time to go, we are only in the preseason, we havent even suited up yet!!..LOL
23, you're right about Beven. I had the pleasure of sitting and talking with him extensively at the annual AMS tropical meteorology conference in Fort Collins several years ago - before he was even doing forecasting at NHC (he was in the satellite analysis segment). While he's a bit of an odd bird, he's tremendously friendly and intelligent. Given his demeanor, though, I wasn't sure how he'd handle the forecasting aspect (he told me at the time he was trying to get into that). He has been a pleasant surprise and has some of the most thorough and accurate analyses to come out of NHC. I'm sure others may have a different opinion of him, based on a forecast here or there, but he's tops in my book. They're not all great and wonderful... I have some serious problems with one of the old-timers there, who shall remain nameless... but Beven has done a spectacular job, especially given the challenges he had to overcome to get into that position. And he's a nice guy on top of that.
Houston and New Orleans RAdar ..Link
incogNeato could not agree more on beven.
Bob makes a great point. We're all itching to get a storm to track/discuss and I think we all get a little impatient at times. We haven't even officially reached the beginning of hurricane season yet. We're all guilty of it to some extent.
I just dont see trofiness like we saw back in 06.Time will tell of course as we get to the meat of the season.

That ridge has been pretty persistant.
23, its been one trough after another along the East Coast this past month. We have set record lows up here in North Florida. If I have to hear the word backdoor cold front again in my forecast I am gonna screem!!..LOL
GFS has been consistent the last few days with the low -- even with the track w/in a few hundred miles -- im becoming more interested any rain would be great
LOL O3!!!!

We'll see how the pattern shapes up in the next few months.
518. FLBoy
I'm with you Tampa....I'm going to wishcast up this GFS forecast the best I can. We have to have the precip!
Posted By: tampaskywatcher at 1:38 PM GMT on May 22, 2007.
GFS has been consistent the last few days with the low -- even with the track w/in a few hundred miles -- im becoming more interested any rain would be great

The GFS has been having a tendency to create TS with any blob out there. I wouldn't by into it.
ITS my wish cast and im stickin with it ! ...lol
Posted By: tampaskywatcher at 1:46 PM GMT on May 22, 2007.
ITS my wish cast and im stickin with it ! ...lol

LOL ok......
522. PBG00
I will wishcast right with ya! A nice healthy T.S. with lots of rain!!!My lawn is crispy and my car is filthy.
i guess i nneed to be around people with a meteorlogical perspective oon this. Or someone who knows how whacky the GFS is.
At least I'm not alone -- lawn -- whats a lawn mine is a brown weedy mess -- long range forecast no longer even includes the wind that was forecast so my hopes are fading with the grass
Morning y'all.

Looks like the CMC is real interested in the E Pac over the next few weeks. Also looks like those troughs that we have been seeing are getting a little weaker. Models don't seem to bring any of them to the E coast over the next two weeks. So although that has been the pattern up till now it looks like it may be starting to change. Shear is still high through the majority of the Atl basin though. So should be at least a couple of weeks before we see anything.
The GFS is usually wrong when it pops storms up all over the place. However, it's not the location and development forecast that always matters. the GFS can be good at picking out the pattern. What the GFS has been seeing lately is the MJO pulse coming east into the Caribbean and setting off convection. It's also seeing the lower wind shear in 2 weeks, so it tries to start developing storms all over the place. Now it may not happen, but it does tell us something about what conditions down there will be like in 10-15 days.
I do understand Drakoen -- apologize just having some fun
Posted By: tampaskywatcher at 2:13 PM GMT on May 22, 2007.
I do understand Drakoen -- apologize just having some fun

i know


Program starts at 11am.
Posted By: hurricane23 at 2:41 PM GMT on May 22, 2007.


Program starts at 11am.

Posted By: hurricane23 at 2:41 PM GMT on May 22, 2007.


Program starts at 11am.

don't like the music though...
It about to start....
536. IKE
MSNBC is suppose to carry it.
Posted By: hurricane23 at 2:56 PM GMT on May 22, 2007.
It about to start....

I am doing work while i am listening.
Standing by.

13 to 17 Named Storms Predicted
Experts at the NOAA Climate Prediction Center are projecting a 75 percent chance that the Atlantic Hurricane Season will be above normal this yearshowing the ongoing active hurricane era remains strong. With the start of the hurricane season upon us, NOAA recommends those in hurricane-prone regions to begin their preparation plans. "For the 2007 Atlantic hurricane season, NOAA scientists predict 13 to 17 named storms, with seven to 10 becoming hurricanes, of which three to five could become major hurricanes of Category 3 strength or higher," said retired Navy Vice Adm. Conrad C. Lautenbacher, Ph.D., undersecretary of commerce for oceans and atmosphere and NOAA administrator. An average Atlantic hurricane season brings 11 named storms, with six becoming hurricanes, including two major hurricanes.

This is the press release-More shortly.
Yeah, the music is pretty weak. :(
...2nd floor men's wear.
543. IKE
It's on MSNBC now.

That music is awful. I closed the window...ugh!
Just started!
H23 I click on that site but don't know where to go can you help me all i get is music
Try again sheri the conference just started.Its also playing on MCNBC.
There just repeating.
548. PBG00
less than impressive
if you were watching on MSNBC they only broadcast the 1st part of the conference.
The main thing to remember is that numbers forcasted are not important its the ones that actually make landfall that matter.It only takes one.
551. PBG00
Maybe thats why is wasn't very impressive..I was watching msnbc
never mind..it's just FEMA blowing smoke now
i completely agree with Hurricane23
554. PBG00
the troubling thing is that they forcast an active season..then people assume every little wave will become a storm and so much is made out of nothing at all..it is maddening sometimes.
No big shocker from NOAA there. Pretty much what I expected.
PBG00 Not everyone waches every little wave. I think us weather bloggers and maybe a few others are the only ones who freak out over little waves unless the NHC mutters something about them to the weather channel.
557. PBG00
I was talking about us weather bloggers
Your right PBG and H23...Esp. if the first few months are inactive or we have several recurving storms, too many ppl will not take the more serious months of Aug-Oct serious enough.
Yeah, I agree Seminolesfan.
Looks like capeverde systems will be back in the mix occording to NOAA.
13 if neutral! up to 17 if La Nina! Possibly more based on the strength of La Nina! Sounds like a good forcast to me!
My best advise is take this time and create that hurricane plan and think about were would you go if your emergency managment officials asked you to leave.

For folks that need help on preparation feel free to visit my hurricane prepardness page on my website.

Page Here
TCW-I think that's an oversimplification to say the least. I'm sure that's not how they came up w/ their forcast.
Afternoon all

Just my take here, but all of this is nonsense. Even the "it only takes one" talk is nonsense. There is no forecasting a season. Look at the last three years. Show me where those forecasts ended up? Tropical season is just a long game of wait and see. Now we are waiting and seeing if the shear dies. Next we will be waiting and seeing where the high sets up. Next we will be waiting to see if the blob forsm, then some waiting and seeing if the high will split or if the trough will get there in time to wisk it out to sea. Wait and see!!!

Again, not trying to offend anyone here, just my take on forecasting of seasons.

That said, we should all take this time to learn and prepare as much as possible.
just my opinion but i think anyone in areas where a hurricane may affect them should stay alert, be prepared for the worst, pray for the best, and just don't be caught off guard

"There is some uncertainty this year as to whether or not La Nia will form, and if it does how strong it will be," said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at the NOAA Climate Prediction Center. "The Climate Prediction Center is indicating that La Nia could form in the next one to three months. If La Nia develops, storm activity will likely be in the upper end of the predicted range, or perhaps even higher depending on how strong La Nia becomes. Even if La Nia does not develop, the conditions associated with the ongoing active hurricane era still favor an above-normal season."

Seems pretty darn close to me!
Actually in my opinion it only takes one is not nonsence at all as alot of folks tend to focus on the numbers predicted.Even a quite season can turn out deadly as 1992 is a prime example of that.

I do agree on preparation as its very important to have and if not create a hurricane plan for you and your family in case your asked to evacuate by your emergency management officals.Take advantage of taz free week on hurricane supplies coming up.

It not the number of storms that form that matters its the ones that actually make landfall that have the greatest impact.
Shear tendency in most of the atlantic and GOM is in the negatives. Maybe another week or two before it becomes generally favorable (Shear-wise) for development.
It's kind of a complicated thing predicting La Nina/El Nino lol. Nobody knows how to accurately predict them yet. We just go by trends and educated guesses mostly. Personally I look at upper-level patters, telleconnections, SST anomalies, and so forth, and then extrapolate what I think the most likely outcome is. For this summer a weak/moderate La Nina is likely.
SW, you can find a lot of good El Nio/La Nia information here.

I got a question for you all on planning and preparing.. I live about three miles from the coast in Pasco Co. FL. We always get the water, and stock up on canned goods. We fill our tanks (cars and grill) and get cash. What do you think is a must have item? I'm thinking this year I might buy a weather radio. Don't think I can afford a generator, but my parents are elderly and not in great health. So, where should I invest my limited funds this year?? thanks.
I agree that a one storm season that is a landfalling 4 or 5 is bad H23, but I don't think that anyone is looking at overall numbers for the season and saying, "well I don't need to keep my guard up." Not to mention most folks stay fairly well informed once a storm is present and moving in the genral direction of land. That is why I say the "only takes one" is not worth a whole lot. Not that it is an false statement, but just that the positive and negative benifits of it right now are minimal.
RMM, hold out as long as you can and buy that generator if you plan on staying. That said, I would also not plan on staying 3 miles from the coast for any storm over a Cat 1, and even then you have to be prepared for a rapidly intensifying storm just in case.

Back to work. Catch y'all later :~)
23 - Evacuating South Florida: Is it even possible ? It seems to me even if all roads were open Northbound, I-95 & the Turnpike, and Millions of people hit the road, it would be a parking lot & now your out there in the open, possibly breaking down or runnning out of gas.At what point would you up and go ? Cat 3 ? Cat 4 ? Or go to the safe room and hope for the best ?
Our Evacuation Zone is D, so we'd be the last told to leave. So far we've never been told to evacuate, but we are always prepared to do so. What they told us in 2005 was if you evacuate to go 10s of miles, not 100s miles. Just get inland basically. They are afraid of masses of people hitting the roads. But after Katrina, I think people will leave more quickly than in the past.

severe weather in alaska lol
Posted By: Hellsniper223 at 3:58 PM GMT on May 22, 2007.
Shear tendency in most of the atlantic and GOM is in the negatives. Maybe another week or two before it becomes generally favorable (Shear-wise) for development.

I think the neg 24 tendendcies are more a result of how high the shear levels have been basin-wide for the last week. It will be quite a while before the upper level westerlies move far enough north to reduce shear over the majority of the atlantic basin.
23 - Evacuating South Florida: Is it even possible ? It seems to me even if all roads were open Northbound, I-95 & the Turnpike, and Millions of people hit the road, it would be a parking lot & now your out there in the open, possibly breaking down or runnning out of gas.At what point would you up and go ? Cat 3 ? Cat 4 ? Or go to the safe room and hope for the best ?
Hi everyone! I can tell u from my experience w/trying to evacuate before Frances. If you are going to leave, do it as soon as we are in definately in the "cone of doom". Drove from Wellington, crept (5hrs.) to Orlando just to be stuck. Couldn't go west or north. ended up turning around to go back home! luckily there was 1 gas station in orlando that had gas (w/ no lines either.) I still find myself asking your question every year though. We are in an impossible area to get out of! I say stock up on gas, food, water, propane, ect. NOW! Beacause as soon as a threat is near, it is pandamonium!
StormW-What's your opinion on the use of GLAAM information to lend further insight into the zonal patterns of upper air movement?
For RMMM34667 and EVERYONE in coastal hurricane areas....GET PREPARED!!!

Generators ARE NOT unafforadable preparations! Considering the need to preserve food, medical needs, cool water, power tool usage, communications, etc., a generator can be a lifesaver for you AND your neighbors (especially the elderly)! My preference is for diesel powered generators as diesel is much safer to store seems to be more available during those critical times.
SW-I mean in terms of forcasting not verification.
watchinwxnwpb...yes, I call that the American 'let them eat cake' syndrome. A lot of people think when the storm comes everyone should just cash out $2,000, fill up the SUV and drive up the coast, when half the people in south Florida don't own a car or a bank account!!
new blog!!!
JusDan~ You are absolutely right. However, most of my family has diesel trucks & it diesel fuel was equally as hard to find. Lots of people have diesel trucks now. Also, I have something for my car. I'm not sure what it is called, but it is a battery charger, has a light on it & it pumps air into your tires. Also it has 2 or 3 outlets to plug things into it. It needs to be charged, but during Wilma we at least had a lamp for light & could charge our cell phones. It helps during the storm until you can use a generator& it's safer than candles or oil lamps. I think it costs like $60.00, but it's a multipurpose worthwhile investment.