ATL: Tropical Depression Edouard

[dhweather]

What is aggravating is people freaking out that it could possibly go into SWLA all the sudden? I think not! That area has been in the Hurricane watch all along! People in the watch should of already been prepared!

You speak wisely.

[hwego7]

Winds up to 45kts at ATCF best track at 00.00 UTC:

This means the NHC is using a 74% reduction factor from the 61kts FL winds. I wonder why they are using 74% instead of 80%-90%?

[Clint_TX]

Well I'm not sure about track, but it's forward speed has slowed, it's blocked to the north and its becoming better organized...what will keep this storm from becoming a strong Cat 1 or Cat 2?

I would like someone to explain why that won't happen.

1) Their is an extremely dry mass of air immediately to the north of Ed in central and southern Mississippi.

2) The flow of that dry air is to the west-southwest. Dry air and tropical cyclones don't mix together well, the dry air wins 99% of the time.

3) Ed is sitting in shallow water. As he churns up that shallow water and cools it off, he will cut his own lifeline if he sits there.

4) There is no significant convection on the western half of the storm, thus it is not symmetrical. Healthy, symmetrical cyclones intensify much faster than disorganized ones like Ed.

5) There's an upper level low over the Yucatan peninsula that is nudging Ed towards the North and is alos interfering with his outflow.

I would be surprised if he's anything more than a weak cat one tomorrow.

This is very good news considering the dense population the storm could possibily impact.

Thanks!

[cheezyWXguy]

Winds up to 45kts at ATCF best track at 00.00 UTC:

This means the NHC is using a 74% reduction factor from the 61kts FL winds. I wonder why they are using 74% instead of 80%-90%?

That was probably put out before those flight level winds were observed. Winds are likely around 50kt by now.

[Extremeweatherguy]

Its looks to me move NW on the Lake Charles radar.

I personally think it is an illusion (but I could be wrong). The strongest band on radar looks to be rotating NW around the center, but the center itself still seems to be moving more W or WNW.

[hwego7]

That was probably put out before those flight level winds were observed. Winds are likely around 50kt by now.

They had it at 40kts on the 7pm update so to bump the winds up 5kts they most certainly were using the 61kt FL wind data from recon.

[Cape Verde]

I still don't see how Edouard hits Galveston/Houston by noon tomorrow. At 7 or 8 mph, it's still 24 hours away.

What am I missing?

[Shockwave]

What is aggravating is people freaking out that it could possibly go into SWLA all the sudden? I think not! That area has been in the Hurricane watch all along! People in the watch should of already been prepared!

Good point. I still am going and am going to stick with my forecast landfall at Beaumont, TX tomorrow afternoon.

[americanrebel]

I still don't see how Edouard hits Galveston/Houston by noon tomorrow. At 7 or 8 mph, it's still 24 hours away.

What am I missing?

That is what I have been trying to figure out my self.

Even if it would turn due NW it would take at least 10 hours to make it to landfall, so if it continues on the W-WNW it will take any wheres from 18 to 30 hours to make landfall.

[cheezyWXguy]

That was probably put out before those flight level winds were observed. Winds are likely around 50kt by now.

They had it at 40kts on the 7pm update so to bump the winds up 5kts they most certainly were using the 61kt FL wind data from recon.

well in that case, they were likely being conservative and winds maybe increased to 50kt at 11pm.

[Extremeweatherguy]

The steering currents show that there is clearly a ridge to the north of this storm. Storms cannot push through such ridges, so a sudden north or even north-northwest turn does not look likely. Yes, there could be wobbles NW at times, but overall I think the general motion will continue to be W or WNW through landfall. My current prediction is for a landfall somewhere between San Luis Pass and Sabine Pass after 12pm tomorrow.

http://cimss.ssec.wisc.edu/tropic/real- ... 8dlm2.html

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[MiamiensisWx]

Well I'm not sure about track, but it's forward speed has slowed, it's blocked to the north and its becoming better organized...what will keep this storm from becoming a strong Cat 1 or Cat 2?

I would like someone to explain why that won't happen.

1) Their is an extremely dry mass of air immediately to the north of Ed in central and southern Mississippi.

2) The flow of that dry air is to the west-southwest. Dry air and tropical cyclones don't mix together well, the dry air wins 99% of the time.

3) Ed is sitting in shallow water. As he churns up that shallow water and cools it off, he will cut his own lifeline if he sits there.

4) There is no significant convection on the western half of the storm, thus it is not symmetrical. Healthy, symmetrical cyclones intensify much faster than disorganized ones like Ed.

5) There's an upper level low over the Yucatan peninsula that is nudging Ed towards the North and is alos interfering with his outflow.

I would be surprised if he's anything more than a weak cat one tomorrow.

1. The dry air was an issue earlier, and I correctly implied that it would "stunt" Edouard's intensification to certain degrees. However, the dry air is much less significant than earlier. Check the local soundings and SKEW-T plots (such as Lake Charles, LA) as of 18Z and compare them to 12Z. The mid level moisture is increasing, while the dry air at the low levels within the boundary layer is mixing out now (at last). Earlier, convection failed to develop and sustain itself over the LLC; tonight is a different story. This TC is likely slowly intensifying now, unlike the situation throughout most of the day.

2. Respectfully, please see response to #1.

3. Remember that tropical cyclones rely on latent heat to support their development and intensification. Edouard is currently over very warm SSTs and recently passed over deep oceanic heat content within the western portion of the Gulf Loop Current. The 26 C isotherm is relatively deep in Edouard's vicinity as well. Note that Edouard will not pass over the cooler SSTs, which are located well SOUTH of Galveston. The near shore SSTs will be warmer in the portion of Gulf from slightly south of Galveston to the Golden Triangle and coast of SW Louisiana. Edouard will make landfall within this region over or slightly NE of the entrance to Galveston Bay. The strong convection and small inner core will aid more greater releases of latent heat, while the increasingly unstable boundary layer will aid more rapid ascent of parcels. With minimal shear and less ML dry air, this supports gradual intensification. Additionally, Edouard will not be crawling at Dolly's rate, and it definitely won't stall. Steering does NOT support a Dolly redux, so upwelling will likely not be a greater issue with Edouard as it moves into the shallower coastal waters. Edouard is a more compact system in terms of aereal extent than Dolly as well, for what it's worth.

4. Please consider the changing thermodynamic environment. A few hours can make a big difference, as we are observing in this case.

5. The upper low has been enhancing ventilation and divergence, as well as outflow. It will continue to aid Edouard in this case, especially as northerly shear has diminished within the past 24 hours. Edouard is now UNDER the H5-H85 ridging.

"It will only be a Cat 1 or weaker..."

Firstly, I personally expect a strong TS at landfall.

Secondly, are you implying that people should stop paying attention to it even as it intensifies?

Thanks...

[MiamiensisWx]

Can you take the Chicago issue to USA Weather? Thanks!

That's significant as well, but it may get confusing in here! It merits its own thread...

[physicx07]

The NHC seems to have a built in hysteresis effect. Over the years watching they don't respond to very rapid changes without other corroborating evidence. Instead they seem to use the systems data from the last few hours, kind of a moving average. I think it's good since strong convection can cause a spike here and there. 61kt flight level would only support 50 kt anyway.

Winds up to 45kts at ATCF best track at 00.00 UTC:

This means the NHC is using a 74% reduction factor from the 61kts FL winds. I wonder why they are using 74% instead of 80%-90%?

That was probably put out before those flight level winds were observed. Winds are likely around 50kt by now.

[cycloneye]

About weather in other places,there is the US Weather forum.

[Stormcenter]

It's almost like we are looking at two different systems here.

http://www.rap.ucar.edu/weather/satelli ... uration=12

[MiamiensisWx]

1) Their is an extremely dry mass of air immediately to the north of Ed in central and southern Mississippi.

2) The flow of that dry air is to the west-southwest. Dry air and tropical cyclones don't mix together well, the dry air wins 99% of the time.

3) Ed is sitting in shallow water. As he churns up that shallow water and cools it off, he will cut his own lifeline if he sits there.

4) There is no significant convection on the western half of the storm, thus it is not symmetrical. Healthy, symmetrical cyclones intensify much faster than disorganized ones like Ed.

5) There's an upper level low over the Yucatan peninsula that is nudging Ed towards the North and is alos interfering with his outflow.

I would be surprised if he's anything more than a weak cat one tomorrow.

1. The dry air was an issue earlier, and I correctly implied that it would "stunt" Edouard's intensification to certain degrees. However, the dry air is much less significant than earlier. Check the local soundings and SKEW-T plots (such as Lake Charles, LA) as of 18Z and compare them to 12Z. The mid level moisture is increasing, while the dry air at the low levels within the boundary layer is mixing out now (at last). Earlier, convection failed to develop and sustain itself over the LLC; tonight is a different story. This TC is likely slowly intensifying now, unlike the situation throughout most of the day.

2. Respectfully, please see response to #1.

3. Remember that tropical cyclones rely on latent heat to support their development and intensification. Edouard is currently over very warm SSTs and recently passed over deep oceanic heat content within the western portion of the Gulf Loop Current. The 26 C isotherm is relatively deep in Edouard's vicinity as well. Note that Edouard will not pass over the cooler SSTs, which are located well SOUTH of Galveston. The near shore SSTs will be warmer in the portion of Gulf from slightly south of Galveston to the Golden Triangle and coast of SW Louisiana. Edouard will make landfall within this region over or slightly NE of the entrance to Galveston Bay. The strong convection and small inner core will aid more greater releases of latent heat, while the increasingly unstable boundary layer will aid more rapid ascent of parcels. With minimal shear and less ML dry air, this supports gradual intensification. Additionally, Edouard will not be crawling at Dolly's rate, and it definitely won't stall. Steering does NOT support a Dolly redux, so upwelling will likely not be a greater issue with Edouard as it moves into the shallower coastal waters. Edouard is a more compact system in terms of aereal extent than Dolly as well, for what it's worth.

4. Please consider the changing thermodynamic environment. A few hours can make a big difference, as we are observing in this case.

5. The upper low has been enhancing ventilation and divergence, as well as outflow. It will continue to aid Edouard in this case, especially as northerly shear has diminished within the past 24 hours. Edouard is now UNDER the H5-H85 ridging.

"It will only be a Cat 1 or weaker..."

Firstly, I personally expect a strong TS at landfall.

Secondly, are you implying that people should stop paying attention to it even as it intensifies?

Thanks...

Bump

[Bailey1777]

It looks on that sat. like the top and bottom are spinning at different speeds?

[Shockwave]

It looks on that sat. like the top and bottom are spinning at different speeds?

Are we looking at a "Day After Tommorrow" type hurricane? Are we going to have two different storms form and one hit LA and the other hit TX? It would make us all wrong! Is that its plan?

[HouTXmetro]

Dr. Lyons said that an area of low pressure formed just to the NW of Edouard....