ATL: TROPICAL DEPRESSION ALEX - DISCUSSION

[Wx_Warrior]

Anyone surprised he's not a hurricane? Had several Cat 1-2-3's on here yesterday.

I slept in...what am I missing?

[americanre1]

According to all these steering models I am looking at http://cimss.ssec.wisc.edu/tropic2/real-time/dlmmain.php?&basin=atlantic&sat=wg8&prod=dlm3&zoom=&time= I don't see anything that is going to move it to the West. I looked at all levels the Ridge to the East is due South to North and the Ridge over the Great Plains is just not that strong right now and looks to be too far south. So am I missing something there???

Personal Forecast Disclaimer:
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.

[dolebot_Broward_NW]

Was just wondering what is going on with this Northern Convective burst, can it actually be breaking away from the main system, as it appears hear? There seems to be a lot going on inside the Gulf of Mexcio.

The gulf states are typically very moist. Having a peek at the soundings around S LA show that the upper levels are conducive to t-storm formation. That is, a lot of CAPE, (potential energy), an unstable environment ( An air parcel stays warmer than the surrounding environment as it ascends and loses heat). There is a bit of a cap, but the LI is at -2.5 and the PWATS are up over 2 inches!

All that weathertalk means that T-storms form practically instantly. Add in the energy of the outflow from a forming cane, and you get yourself some thunderstorms. There doesn't seem to be any cyclonic spin, and its fairly typical sheared off energy. It won't form anything while directly in the flow of a much stronger system. It'll die down before too long.

[americanre1]

Was just wondering what is going on with this Northern Convective burst, can it actually be breaking away from the main system, as it appears hear? There seems to be a lot going on inside the Gulf of Mexcio.

The gulf states are typically very moist. Having a peek at the soundings around S LA show that the upper levels are conducive to t-storm formation. That is, a lot of CAPE, (potential energy), an unstable environment ( An air parcel stays warmer than the surrounding environment as it ascends and loses heat). There is a bit of a cap, but the LI is at -2.5 and the PWATS are up over 2 inches!

All that weathertalk means that T-storms form practically instantly. Add in the energy of the outflow from a forming cane, and you get yourself some thunderstorms. There doesn't seem to be any cyclonic spin, and its fairly typical sheared off energy. It won't form anything while directly in the flow of a much stronger system. It'll die down before too long.

Even though it has been there for the past 2 days, it will die down??? And yesterday there was a MLC in there.

[dolebot_Broward_NW]

The proper steering layer:

http://cimss.ssec.wisc.edu/tropic2/real ... oom=&time=

shows the Atlantic ridge, forecast by models to build to the W, as the player here.

[tolakram]

Anyone surprised he's not a hurricane? Had several Cat 1-2-3's on here yesterday.

I slept in...what am I missing?

It's June.

[KWT]

Its got a very slack wind gradient, with several wind maxes...its like what Ike had when it was in the Gulf...but without the eyewalls!

Your going to relaly struggle to get much above 75kts with that profile and even that maybe too high if it can't strengthen its eyewall.

[dolebot_Broward_NW]

Even though it has been there for the past 2 days, it will die down??? And yesterday there was a MLC in there.

Think about whats happening, then think about how typical storms (continental, non-tropical ones) are formed.

You have moderate flow over a large area of moisture at the surface. This is the inflow to the storm.

You have lighter flow aloft over the same area. The area is unstable and sheared. It is more like a baroclinic front than anything tropical.

[americanre1]

The proper steering layer:

http://cimss.ssec.wisc.edu/tropic2/real ... oom=&time=

shows the Atlantic ridge, forecast by models to build to the W, as the player here.

Yeah but it looks like the outer bands are not that strong, so why would it turn this system so sharply. If this system keeps the upper body it should either separate from the main body or block all this upper ridge from building in too strong, so this storm should continue its NNW to NW movement for the future until there is something strong to actually stir this. With this forward speed increasing, is there a chance that Alex is trying to shoot for the weakness in between the two upper level highs?

Personal Forecast Disclaimer:
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.

[HURAKAN]

Getting that look

[HURAKAN]

Latest

[KWT]

It really needs to stop allowing that drier air getting into the center of the circulation, if it can do that then strengthening will happen...

I'm still very wary of a system that has winds as high at 100 miles out of the center as the 'eyewall'...that doesn't scream healthy to me!

[A1A]

Looks like it is pushing the dry air band into Texas.

[dolebot_Broward_NW]

is there a chance that Alex is trying to shoot for the weakness in between the two upper level highs?

Weak storms are steered more by lower level flow than flow aloft. This is because the bulk of the storm is not up past 400mb. Once you get strong and a good amount of the storm exists over 400mb, the upper atmosphere is far more energetic and the storm is steered by the upper layers.

The layer mean analysis by WISC isn't gospel. Another place you can see is to view the mandatory level plots via Unisys here:

http://weather.unisys.com/upper_air/ua_400.html

You can see the great plains/4 corners ridge and the Atlantic ridge, bridge falls apart between 400 and 500mb. SO if this guy gets much stronger, sure theres a chance he'll follow more of the 400mb level, which has him going NW in the short term and following the ridge into the panhandle FL.

However, recall that every model seems to have the Atlantic ridge building back into the gulf.

[TexWx]

"It really needs to stop allowing that drier air getting into the center of the circulation"

I thought this was hilarious, don't know why....
Continue

[HURAKAN]

"It really needs to stop allowing that drier air getting into the center of the circulation"

I thought this was hilarious, don't know why....
Continue

You know it comes from a hurricane nut!! I would have said the same!!!

We seem to be pro-hurricane!!!!!

[jasons2k]

Unless it loses the banding and develops a solid eyewall, a peak of 65-75 kt seems reasonable. I wouldn't even count out weakening back to a TS before landfall on that.

Yeah I agree, its got good convective bursting but the banding is going to allow that dry air that is between the center and the northern convective mass to work its way into the circulation still and limit how strong it could become.

Yes, that seems to be the key at this point. The image posted by Hurakan above is telling. A dry slot wrapped all the way into almost the center. Alex is starting to run out of time for any substantial intensification before landfall. I no longer think this could make major status before LF (not that I thought it would, but yesterday I thought maybe it could); a solid Cat 1 seems most reasonable to me at this point.

[wx247]

I agree jason. It appears to me at this point that heavy rain and flooding may wind up being the primary impact from Alex.

[A1A]

Wow getting some rain showers now from a rainband - all the way in interior central Texas. Cool we need it!

[lrak]

The visible loop is giving the appearance of another Northerly jog?