Trop./subtropical formation in Caribbean in coming weeks #2

[Jim Hughes]

It is just amazing how these long range forecasts, by the models, are usually centered around the peak time of the space weather variables that I have continually written about.

We saw this occur with an outllook for the EPAC early last week and for the GOM /Texas area in the upcoming 48 hours or so. (From the threads that I have beeing reading.)

Take a look at the ACE2 hourly solar wind data for May. Look under the Solar Wind Bulk Speed heading. You will notice how it peaked around the forecast time of the EPAC.

It currently is hovering around the 500 km/sec range . (Forecast time of GOM storm) And it will be peaking again in early June because of the effects of a recurrent coronal hole. (This is the time frame of next possible storm that is forecasted)

http://www.sel.noaa.gov/ftpdir/lists/ac ... pam_1h.txt

This is why I have always contended that this is like a two part equation. The atmospheric variables that are needed for storm formation, are already in place because of how the earth's electrical environment continually interacts with the IMF changes. Then it gets the right push when the proper space weather variables occur.

The models will tend to forecast events way out during the times of repetitive space weather variables. Like recurrent coronal holes. Which cause the solar wind speed to go up.

But they will be somewhat surprised when a sunspot region rapidly develops. (Outlooks should come together closer to storm formation) A magnetically complexed sunspot region increases the chances of solar eruptions. Which then increases particle levels. This is when most of your Atlantic Cat 5's form.

[cheezyWXguy]

GFS has something June 4th in the southeast Gulf. But the GFS that far out is like throwing darts at a bulls eye on a 100 foot wall.

whoa...When i was scrolling down this thread I was thinkin the same exact thing

[drezee]

NAM is now on board


NAM Model

[brunota2003]

uh...you are only supposted to provide either a link or a thumbnail image...please proceed to do that

[cycloneye]

drezee I fixed the link to make it a hypertext and not have a huge graphic.

[drezee]

uh...you are only supposted to provide either a link or a thumbnail image...please proceed to do that

Someone already did

[brunota2003]

thank you...and you to cycloneye...much faster loading now

[drezee]

NAM even has a small center there...

[Rainband]

aint buying it. As time goes by maybe. But as said before Long range models......

[drezee]

aint buying it. As time goes by maybe. But as said before Long range models......

The NAM is a short range model. 84 hour forecast

[Rainband]

aint buying it. As time goes by maybe. But as said before Long range models......

The NAM is a short range model. 84 hour forecast

My bad. I thought you were talking about the june 4th gfs run. I see it says the 24th on the nam. I still don't buy it Stranger stuff has happened but I would be really surprised.

[HurricaneHunter914]

http://cimss.ssec.wisc.edu/tropic/real- ... wg8sht.GIF

HOLY CRAP! Look at this shear map! The shear right now is super low in the Caribbean and the shear is staring to weaken in the GOM! We could have a named storm form right now if a system forms!

[CHRISTY]

I say from around MAY 24 to JUNE 24 we might see something get going!thats the timeframe iam thinking right now....

[wxman57]

http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8sht.GIF

HOLY CRAP! Look at this shear map! The shear right now is super low in the Caribbean and the shear is staring to weaken in the GOM! We could have a named storm form right now if a system forms!

Be careful, that's not a shear map, it's a shear TENDENCY map. The map indicates only that the shear has dropped a little in the Gulf and Caribbean, it doesn't indicate what the actual shear is.

[Audrey2Katrina]

I say from around MAY 24 to JUNE 24 we might see something get going!thats the timeframe iam thinking right now....

Now there's a bold prediction!

I'll be a little more conservative and say somewhere within the next 2400 hours we will almost certainly have our first named storm.


Upper Caribbean, SE Gulf looks like a starter.

A2K

[CHRISTY]

http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8sht.GIF

HOLY CRAP! Look at this shear map! The shear right now is super low in the Caribbean and the shear is staring to weaken in the GOM! We could have a named storm form right now if a system forms!

yea shear is low in the carribean but it is still high across the gulf of mexico and most of the atlantic.It is expected to stay this way about the next 4 days...There is indeed pockets of light shear in the SW carribean and in the SE Atlantic.

[GeneratorPower]

16 days should not even be used for trends. The system of PDEs cannot be solved with that level of accuracy that far out numerically, too much error comes into play.

Model data should really only be considered about 5-7 days in advance

I agree. But why, then, does a 16 day GFS even exist at all? Shouldn't the modeling folks keep the extended period under wraps until it proves at least mildly effective?

I'm not an advocate for stopping the flow of information, but it begs the question "Why don't they go out to 20 days?" What makes 16 days a good stopping point?

[curtadams]

16 days should not even be used for trends. The system of PDEs cannot be solved with that level of accuracy that far out numerically, too much error comes into play.

Model data should really only be considered about 5-7 days in advance

I agree. But why, then, does a 16 day GFS even exist at all? Shouldn't the modeling folks keep the extended period under wraps until it proves at least mildly effective?

I'm not an advocate for stopping the flow of information, but it begs the question "Why don't they go out to 20 days?" What makes 16 days a good stopping point?

The gfs is used for many things other than predicting hurricanes. Many other things like front placement are far less sensitive to exact details than cyclone prediction and so you do get something useful (if not very) from a 16-day model.

[Rainband]

Our NWS discussion uses the gfs all the time

[boca]

http://www.ssd.noaa.gov/goes/east/watl/loop-avn.html

Interesting blow up of thunderstorms down there.