ImpactWeather's Prediction

[Blown Away]

They breakdown the factors that may lead to a busy hurricane season and their graphics target SFL, NGOM, NC, and entire Caribbean (Not really going out on a limb). Chris Hebert talks about lower pressures in the Atlantic basin will increase tropical activity. He also talks about westward moving systems being drawn into SFL and NGOM due to the low pressure over the SE CONUS. I get his point, but I think the EC trough will pull systems north out of the Caribbean towards SFL & NGOM and the systems that skirt N of the islands will recurve or may impact NE CONUS. Speaking for SFL, when I hear EC trough going to be in place I look S instead of E during Aug/Sept.
Home Page: http://www.impactweather.com
Predictions: http://www.youtube.com/impactweather#p/u/4/XDMirZI5_Ic

[floridasun78]

the reason he say sfl downgun because of strong high that forecast to be post doing aug and sep peak part of season that pull all system toward west the trough are not expect to be strong during those month i want hear met what saying on this

[Blown Away]

the reason he say sfl downgun because of strong high that forecast to be post doing aug and sep peak part of season that pull all system toward west the trough are not expect to be strong during those month i want hear met what saying on this

When does he state a strong high during peak season? I heard him say the lower pressure of SE CONUS and a weak Bermuda High?

[KWT]

A weak Bermuda high doesn't really matter, what matters is where the mean ridge is forecasted, if the mean ridge sits between 80-65W its going to funnel everything towards the east coast...but we shall see!

[wxman57]

One thing I'm noticing is that the ridge over the central U.S. and the East U.S. Coast trof may be setting up a bit farther east than forecast (though they reposition from week to week). This may open up the NW Gulf to a significant landfall more so than if the high over the central U.S. was stronger, forcing the storms westward into Mexico. Bottom line is that there appears to be an increased risk of landfall just about everywhere this season.

The e-transit.org hurricane landfalling project has calculated the landfall chances in 2010 (vs. climo) for the entire U.S. Coast:

http://e-transit.org/hurricane/welcome.html

[Blown Away]

One thing I'm noticing is that the ridge over the central U.S. and the East U.S. Coast trof may be setting up a bit farther east than forecast (though they reposition from week to week). This may open up the NW Gulf to a significant landfall more so than if the high over the central U.S. was stronger, forcing the storms westward into Mexico. Bottom line is that there appears to be an increased risk of landfall just about everywhere this season.

The e-transit.org hurricane landfalling project has calculated the landfall chances in 2010 (vs. climo) for the entire U.S. Coast:

http://e-transit.org/hurricane/welcome.html

Wxman57, are we able to get a sense on where the average position of the BH may be during the next month or so and how will that effect tracks towards SFL or EC?

[Florida1118]

It seems Florida Gets something somewhere in the state virtually every year, so im going to bank something will hit, especially in a active year. Impactweather.com said that the chances might shift more east, because of the high and its placement.

[wxman57]

One thing I'm noticing is that the ridge over the central U.S. and the East U.S. Coast trof may be setting up a bit farther east than forecast (though they reposition from week to week). This may open up the NW Gulf to a significant landfall more so than if the high over the central U.S. was stronger, forcing the storms westward into Mexico. Bottom line is that there appears to be an increased risk of landfall just about everywhere this season.

The e-transit.org hurricane landfalling project has calculated the landfall chances in 2010 (vs. climo) for the entire U.S. Coast:

http://e-transit.org/hurricane/welcome.html

Wxman57, are we able to get a sense on where the average position of the BH may be during the next month or so and how will that effect tracks towards SFL or EC?

It's constantly changing, but it seems quite strong enough to provide a significant threat to the Gulf of Mexico and southeast U.S.

[Blown Away]

Thanks Wxman57!! How is the 2010 setup different from 2005. In 2005 almost every system the developed E of 60W went N and the systems the developed W of 60W were pushed into the GOM.

[brunota2003]

I disagree with part of their assessment. Neutral (and especially La Nina) years elevate the threat to Texas. FL, TX, and NC are at the highest risk of a landfall during a La Nina year (meaning direct strike, not including the effects a system can cause!!!), in that order. LA is not too far behind NC. <-- That based off of a study I did from 1980 to 2009.

[wxman57]

I disagree with part of their assessment. Neutral (and especially La Nina) years elevate the threat to Texas. FL, TX, and NC are at the highest risk of a landfall during a La Nina year (meaning direct strike, not including the effects a system can cause!!!), in that order. LA is not too far behind NC. <-- That based off of a study I did from 1980 to 2009.

Looking a the 6 analog years they cited in the text version of the outlook, there were no significant impacts on the TX coast in any analog year. Hits were concentrated on the Yucatan then Mexico or the southeast U.S. Now that's not to say Texas is safe. All areas on that map indicate an elevated risk over climatology, though some areas have a significantly greater risk of an impact. And with the mean ridge axis over the U.S. a bit east of the forecast, that could open up the TX coast to a landfall instead of the high pressure forcing them west into Mexico.

[brunota2003]

I disagree with part of their assessment. Neutral (and especially La Nina) years elevate the threat to Texas. FL, TX, and NC are at the highest risk of a landfall during a La Nina year (meaning direct strike, not including the effects a system can cause!!!), in that order. LA is not too far behind NC. <-- That based off of a study I did from 1980 to 2009.

Looking a the 6 analog years they cited in the text version of the outlook, there were no significant impacts on the TX coast in any analog year. Hits were concentrated on the Yucatan then Mexico or the southeast U.S. Now that's not to say Texas is safe. All areas on that map indicate an elevated risk over climatology, though some areas have a significantly greater risk of an impact. And with the mean ridge axis over the U.S. a bit east of the forecast, that could open up the TX coast to a landfall instead of the high pressure forcing them west into Mexico.

Perhaps during the years that they use as analog. All I did was compare El Nino/Neutral/La Nina years between 1980 - 2009 and what states had landfalls. Texas was at most risk during a La Nina year, with 71.4% of all La Nina years having a landfall in Texas (granted there were only 7 La Nina years out of the total of 30).

But, during an El Nino year, Texas was only hit 30% of all 10 years, and Neutral jumps to 53.8% out of the 13 years. So, it definitely seems like global conditions during a La Nina year more favor a Texas hit than during an El Nino year (note that the study counted everything tropical from a TD on up...but I did not count subtropical systems).

[MWatkins]

I have been on record, many many times, that this kind of forecast is irresponsible, sends the WRONG kind of message and are virtually unverifiable.

I searched http://www.impactweather.com for forecast verification information...and predictably could not find anything. Maybe verification is available only to clients, but I have a feeling it's not a part of what's given to people wanting to know how skillfull this (and other private forecasting services) are.

For example, this is a paragraph explaining the services that this site offers:

Knowing just when to expect the arrival of a hurricane's effects and how severe they might be is vital to your operations. Our full suite of TropicsWatch services includes advanced mapping systems and the latest storm imagery. You'll be able to step through a series of maps in increments in order to visualize just how and when the effects of a hurricane will impact your area of concern. We'll even plot your location (or locations) right on the maps.

Really? How and where? In what time frame? The NHC can't do this more than 12 hours in advance. Getting the core of a hurricane is much different than getting a fringe effect. Are you telling me that Impact Weather can make a map of this DAYS in advance? This is a fluffy sales pitch, making it seem like they are the only ones who know.

Heck, Hurrtrack (software) can do this based off of the NHC forecast track...and I would bet the farm the cost of the software is much cheaper than retaining a private company to make pretty graphics to aimed to help their clients feel better.

I appreciate the link, and I realize this thread was started as an attempt to inform members about a forecast from a private firm.

However, the lack of transparency, the vague nature of the forecast map, and the lack of objective data abailable to determine the skill of the forecast lends me to question the validity of the claims this paticular company is making. Worse, I think the "threat" graphic is a bad idea to propogate.

When a storm is on the map, we don't know where it's going to go three days from now...

How can you possibly know what storms are going to do when they haven't even developed yet????? And you can't say it's probability...an "elevated" risk area may go from 1% average to a 2% probability, which is a 100% increase over norm. But does 2% really require a big red highlight? Nope.

Unreal. Everyone should prepare. Every area of the coast has an elevated risk during a hyperactive year like this one is forecast to be.

I am personally getting tired of this silly game...which is one of the main reasons I stopped doing the radio show a couple of years ago.

MW

[lonelymike]

MW,
I'm surprised by your post. I've always read your posts with respect because you've always had something positive to add or say. Obviously not this time. I'm not going to defend Impact weather per say. But I will say I have seen their product and their forecasts for a couple of years and they are pretty good at what they do. A lot of their clients are oil companies, industry and county emergency managment and they provide a detailed forecast specifically geared to that client's need. I see your point and you have every right to say your view. But next time maybe it do in a more classy manner I guess the word I'm looking for. As far as the radio show I'm sorry you no longer are able to do it but maybe there is a reason why.

[wxman57]

Actually, the risk of a hurricane impact on Florida this year is about 20-25% higher than average. You can check out the calculated probabilities at the sites below (CSU and Bridgewater Colleges).

Main Site:
http://www.e-transit.org/hurricane/welcome.html

Hurricane Probability Data:
http://landfalldisplay.geolabvirtualmaps.com/

I made a snapshot of their (CSU & Bridgewater) calculated probabilities of a landfalling hurricane and major hurricane for the various states for 2010 vs. climatology. Quite significant values over climatology from the Carolinas westward to Texas. Much lower probabilities north of Virginia. The highest concentration of landfalling hurricanes in the analog years was from the mid Gulf Coast through south Florida, the Carolinas, and northern Mexico (south of TX).

[KWT]

Wow Florida upto 75%, a jump of 24% from the norm, thats certainly very high risk of landfall.

I'd just mention if there was one place prone to landfalling systems in La Nina, esp during October, it'd be the Yucatan. We've already sorta seen it with Alex though it was weak, but I'm expecting probably a major landfalling hurricane on the Yucatan. Just every decent strength La Nina in the last 60 years has had a major hurricane hitting the Yucatan/CA regions, some like 2007 had multiple hits.

[Florida1118]

Actually, the risk of a hurricane impact on Florida this year is about 20-25% higher than average. You can check out the calculated probabilities at the sites below (CSU and Bridgewater Colleges).

Main Site:
http://www.e-transit.org/hurricane/welcome.html

Hurricane Probability Data:
http://landfalldisplay.geolabvirtualmaps.com/

I made a snapshot of their (CSU & Bridgewater) calculated probabilities of a landfalling hurricane and major hurricane for the various states for 2010 vs. climatology. Quite significant values over climatology from the Carolinas westward to Texas. Much lower probabilities north of Virginia. The highest concentration of landfalling hurricanes in the analog years was from the mid Gulf Coast through south Florida, the Carolinas, and northern Mexico (south of TX).

Hmmm...75%? but TX only 54%? Why are we 21% above them? Are they expecting later in the season something? BTW, Does anyone know there Percentages from 2004/05?

[wxman57]

Actually, the risk of a hurricane impact on Florida this year is about 20-25% higher than average. You can check out the calculated probabilities at the sites below (CSU and Bridgewater Colleges).

Main Site:
http://www.e-transit.org/hurricane/welcome.html

Hurricane Probability Data:
http://landfalldisplay.geolabvirtualmaps.com/

I made a snapshot of their (CSU & Bridgewater) calculated probabilities of a landfalling hurricane and major hurricane for the various states for 2010 vs. climatology. Quite significant values over climatology from the Carolinas westward to Texas. Much lower probabilities north of Virginia. The highest concentration of landfalling hurricanes in the analog years was from the mid Gulf Coast through south Florida, the Carolinas, and northern Mexico (south of TX).

http://myweb.cableone.net/nolasue/prob.gif[

Hmmm...75%? but TX only 54%? Why are we 21% above them? Are they expecting later in the season something? BTW, Does anyone know there Percentages from 2004/05?

Check out the "normal" (climo) year probability for Florida vs. Texas - 51% vs. 33% (an 18% difference). Florida has a much longer coastline and it sticks out like a sore thumb, so its chances of being hit are fairly high in any one year. Now keep in mind that these predictions of increased probability of landfall in one area or another isn't done by putting current data into a model and predicting paths months in advance. It's simply done by identifying landfall points in analog years, years with a similar setup of Atlantic and Pacific oceanic temperatures and atmospheric flow patterns and inferring that similar landfall patterns might develop in 2010.

[MWatkins]

MW,
I'm surprised by your post. I've always read your posts with respect because you've always had something positive to add or say. Obviously not this time. I'm not going to defend Impact weather per say. But I will say I have seen their product and their forecasts for a couple of years and they are pretty good at what they do. A lot of their clients are oil companies, industry and county emergency managment and they provide a detailed forecast specifically geared to that client's need. I see your point and you have every right to say your view. But next time maybe it do in a more classy manner I guess the word I'm looking for. As far as the radio show I'm sorry you no longer are able to do it but maybe there is a reason why.

You know what, Lonelymike?

You're right. I took out my frustration with the hurricane game on Impact.

I am sure there are a lot of good services they provide beyond just hurricane forecasting...and it was irresponsible of me to tee off on that company when there are so many others out there doing worse stuff.

Thank you for pointing this out...I appreciate it.

MW