Tropical Storm Edouard

[vortex95]

7 minutes ago, WxWatcher007 said:

2026 in a nutshell? Yeah. I'm not flying down.  

As hurting as the convection is, at least it is nicely circularly-banded and looks more like a classic TC.  Did not have that at all w/ Arthur, Bertha, Cristobal, or Dolly.  Shear was the big issue for those.  Edouard's issue is dry air, but you can do a bit better overall for max TC intensity when only dry air is an issue I have noticed empirically.

[WxWatcher007]

Tropical Storm Edouard Discussion Number   3
NWS National Hurricane Center Miami FL       AL052026
1000 PM CDT Mon Aug 31 2026
 
Satellite and radar data showed an increase in banding near the 
center of the small tropical cyclone during the late afternoon and 
early evening hours.  Subjective and objective satellite intensity 
estimates increased to around 35-40 kt, and the initial wind speed 
was therefore increased to 35 kt on the 0000 UTC intermediate 
advisory.  Since that time, there has been a pause in the 
organization of the system, but curved bands are noted over the 
northern and western portions of the circulation. An Air Force 
Reserve reconnaissance aircraft that has been sampling the system 
this evening reported earlier that the pressure has fallen to 
around 1004 mb, which is quite a bit lower than from this 
afternoon's mission, though the last fix was up a millibar or two.  
The flight-level winds do not appear to have responded to the 
pressure drop yet, so the initial intensity remains 35 kt for this 
advisory.
 
Edouard will be moving over very warm waters of the northwestern
Gulf within a low shear and a sufficiently moist environment
tonight and Tuesday morning.  As a result, nearly all of the
dynamical models indicate that the system will strengthen on its
approach to the coast, with most showing much of the strengthening
occuring in the final hours before landfall.  Given that the system
is small, a period of quick organization and strengthening seems
likely Tuesday morning.  The NHC forecast calls for intensification
during the next 12 hours and additional strengthening could result
in Edouard nearing hurricane strength when it approaches the
coast on Tuesday. Therefore, a Hurricane Watch and Storm Surge
Warning has been issued for a portion of the northwest Gulf coast
with this advisory. The NHC intensity forecast is near the upper-end
of the guidance envelope. Note that since the peak intensity is
expected to occur at landfall (between the 12 and 24 hour forecast
points), it is not possible to explicitly reflect Edouard's peak
intensity in the forecast points below.
 
Edouard is moving west-northwestward or 300/6 kt.  A low- to
mid-level ridge over the southeastern United States is expected to
steer the cyclone toward the west-northwest to northwest during the
next couple of days. This motion should bring the center onshore
along the northwestern Gulf Coast on Tuesday and inland over eastern
Texas Tuesday night.  The track guidance is in good agreement on
this scenario and the new NHC track forecast is essentially an
update of the previous track.
 
 
Key Messages:
 
1. Edouard is expected to strengthen and it could approach
hurricane strength before it reaches the northwest Gulf Coast on
Tuesday. Tropical Storm conditions are expected along the northwest
Gulf Coast with hurricane conditions possible from High Island to
Cameron.
 
2. A Storm Surge Warning has been issued from High Island, Texas to
the Vermilion/Cameron Parish Line, Louisiana where peak values of
3 to 5 feet above ground level are possible along the immediate
coast within the warning area.
 
3. Heavy rain will impact parts of the Upper Texas coast through 
east-central Texas into far Southwest Louisiana Tuesday and 
Wednesday as Tropical Storm Edouard tracks inland. Flash flooding is 
likely across this region, especially in urban areas. River flooding 
may also be possible.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  01/0300Z 28.6N  91.8W   35 KT  40 MPH
 12H  01/1200Z 29.2N  93.0W   50 KT  60 MPH
 24H  02/0000Z 30.1N  94.3W   40 KT  45 MPH...INLAND
 36H  02/1200Z 31.1N  95.4W   30 KT  35 MPH...INLAND
 48H  03/0000Z...DISSIPATED
 
$$
Forecaster Brown

[vortex95]

42 minutes ago, WxWatcher007 said:

Dry air definitely still looks to be an issue, and that was a clear limiting factor even when this was a lemon. I agree that there's no one size fits all for TCs, which is why the Twitter conversation sometimes gets frustrating because cold top convection does not automatically equal RI. You can see the dry air on the northern flank clearly, and it seems clear that it's having an impact, though I think the expanding outflow on the northern side of Edouard does limit it some. 

 

I've always been of the opinion that you need organization before substantial intensification so that's what I look for. Today we've seen substantial progress in that department. We went from a weak and elongated low this morning

To a much tighter wind field, with a meaningful pressure drop this evening on the first recon pass of the evening. 

I still think an overnight/morning convective burst aided by diurnal maximum given the developing inner core should allow for modest intensification, with an added boost from frictional convergence. Like someone else said earlier, I think this is one of those short fuse homebrew cases where we do say if this had more time it could have intensified more substantially. Regardless, it will be interesting to watch given the radar coverage we will have from now through landfall. Tonight I'll be watching to see 1) if the reduction in central convection leads to a collapse in the nascent inner core and if not 2) how soon we see the overnight convective burst I'm expecting. 18z HAFS has that happening around 5am. 

Some get *far* to impressed w/ large MCS areas w/ very cold cold tops for nascent TCs.  Yes it is intense convection, but that does not correlate well when it blows up very fast b/c that often mean it will dissipate just as fast.  And the collapsing convection hinders organization at low-levels, .It can also happen when a system of mdt TS status.  You get this immense area of very cold cloud tops, sometimes below -100 C, in a rather symmetric blob, calked a CCC, but there is no banding.  When this happens, the TC often is stunted in intensification until the CCC feature goes away.

If Edouard has a blow up of convection overnight, watch closely,  Does it form in a coherent band as we are seeing on the N side now, or is is just random blobs (zits!) expanding radially?  Also, you can have a combo of this.

Banding now on the N side is good, but nothing on the S side,  This implies dry air wrapping in.  Also, the banding on the N side may be due to frictional convergence from the LA coast.  Still, that can increase max winds b/c the stronger convection mixed down higher winds aloft better and the band is pushing against weak high pressure to the NE

[vortex95]

1 minute ago, WxWatcher007 said:

Tropical Storm Edouard Discussion Number   3
NWS National Hurricane Center Miami FL       AL052026
1000 PM CDT Mon Aug 31 2026
 
Satellite and radar data showed an increase in banding near the 
center of the small tropical cyclone during the late afternoon and 
early evening hours.  Subjective and objective satellite intensity 
estimates increased to around 35-40 kt, and the initial wind speed 
was therefore increased to 35 kt on the 0000 UTC intermediate 
advisory.  Since that time, there has been a pause in the 
organization of the system, but curved bands are noted over the 
northern and western portions of the circulation. An Air Force 
Reserve reconnaissance aircraft that has been sampling the system 
this evening reported earlier that the pressure has fallen to 
around 1004 mb, which is quite a bit lower than from this 
afternoon's mission, though the last fix was up a millibar or two.  
The flight-level winds do not appear to have responded to the 
pressure drop yet, so the initial intensity remains 35 kt for this 
advisory.
 
Edouard will be moving over very warm waters of the northwestern
Gulf within a low shear and a sufficiently moist environment
tonight and Tuesday morning.  As a result, nearly all of the
dynamical models indicate that the system will strengthen on its
approach to the coast, with most showing much of the strengthening
occuring in the final hours before landfall.  Given that the system
is small, a period of quick organization and strengthening seems
likely Tuesday morning.  The NHC forecast calls for intensification
during the next 12 hours and additional strengthening could result
in Edouard nearing hurricane strength when it approaches the
coast on Tuesday. Therefore, a Hurricane Watch and Storm Surge
Warning has been issued for a portion of the northwest Gulf coast
with this advisory. The NHC intensity forecast is near the upper-end
of the guidance envelope. Note that since the peak intensity is
expected to occur at landfall (between the 12 and 24 hour forecast
points), it is not possible to explicitly reflect Edouard's peak
intensity in the forecast points below.
 
Edouard is moving west-northwestward or 300/6 kt.  A low- to
mid-level ridge over the southeastern United States is expected to
steer the cyclone toward the west-northwest to northwest during the
next couple of days. This motion should bring the center onshore
along the northwestern Gulf Coast on Tuesday and inland over eastern
Texas Tuesday night.  The track guidance is in good agreement on
this scenario and the new NHC track forecast is essentially an
update of the previous track.
 
 
Key Messages:
 
1. Edouard is expected to strengthen and it could approach
hurricane strength before it reaches the northwest Gulf Coast on
Tuesday. Tropical Storm conditions are expected along the northwest
Gulf Coast with hurricane conditions possible from High Island to
Cameron.
 
2. A Storm Surge Warning has been issued from High Island, Texas to
the Vermilion/Cameron Parish Line, Louisiana where peak values of
3 to 5 feet above ground level are possible along the immediate
coast within the warning area.
 
3. Heavy rain will impact parts of the Upper Texas coast through 
east-central Texas into far Southwest Louisiana Tuesday and 
Wednesday as Tropical Storm Edouard tracks inland. Flash flooding is 
likely across this region, especially in urban areas. River flooding 
may also be possible.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  01/0300Z 28.6N  91.8W   35 KT  40 MPH
 12H  01/1200Z 29.2N  93.0W   50 KT  60 MPH
 24H  02/0000Z 30.1N  94.3W   40 KT  45 MPH...INLAND
 36H  02/1200Z 31.1N  95.4W   30 KT  35 MPH...INLAND
 48H  03/0000Z...DISSIPATED
 
$$
Forecaster Brown

IMHO, I think they are really pushing the limit for  HU watch here.  Yes, the pressure is down, but the convective area waned considerably at the time until about an hor ago, yet NHC did not even acknowledge this clear cycle down on sat?  Again, I think they tend to not include if they can anything that show weaker or a struggle, but as posts noted on the thread in the last few hours, Edouard looks not so good (skeletal).  So I am just speaking out loud here what others might be thinking as well and not thinking in an isolated vacuum!

Yes, the risk is there, but err'ing on the side of caution I find influence more by social pressure rather than sticking to the met science these days, which has advanced big time over the decades.  And, yes, I am aware of what HU Humberto did in Sep 2007 in the very same area, but that was an exceptional event, no other like that on record, so that alone is not enough.  Also objectively, current environmental conditions concerning dry air are a sig problem as evidenced by the wane of convection earlier and what we see just to the N on the mid-level WV, so that would count against such aggressive RI.

All I am saying is that the door swings both ways here, so in Edouard's case given the factors, IMHO would be more logical/practical to split it down the middle (steady but more modest straightening). rather than chose any one clear direction until we actually see evidence of RI. esp on satellite/radar and it being in a data rich area.  It's not like we will be in the dark as to trends hour-by-hour.  Lots of platform sfc obs off the LA coast, as one example.

I know I am verbose and sound pedantic, but it shows how there is a *lot* to consider in TC forecasting, and forecasting in general.  How one chose to go in any given situation is subjective of course.  My position is that I do not go high aggressive in a forecast until I see clear reason to do so ((in other words, not forecast an outlier, rare, or exceptional event unless it is clear it has a good chance of occuring), and the amount of wx data and its detail these days, one can afford to "wait and see" more IMHO.

[Scott747]

43 minutes ago, WxWatcher007 said:

2026 in a nutshell? Yeah. I'm not flying down.  

Hey at least it's a chasable track now.

82 between Port Arthur and Holly Beach has a couple of bridges to take refuge on with a weaker storm like this when surge comes in.

Of course they are teasing you with the hurricane watch not to mention recon with the 'eyewall beginning to form.

 

[Floydbuster]

https://www.youtube.com/watch?v=2i4xnjcMme0

[Chinook]

small feature that looks like an eye, but of course a true eye should come with a hurricane

 

[vortex95]

13 minutes ago, Chinook said:

small feature that looks like an eye, but of course a true eye should come with a hurricane

 

Yes, you can get mid-level eyes appear even in the TD stage. 

In this case, since there is no deep convection over the center, it is lower-level feature w/ shallow convection around it that makes it look like an eye.

Look at the platform obs to the SW.  NE winds?  Talk about a small circulation!

The small TC for rapid intensity changes is tricky.  A small TC is more sensitive to dry air intrusions or shear than a larger one, but at the same time, having a small RMW promotes RI easier.  Mesoscale factors in the inner core come into play, and are very tough to fcst.  Recall HU Oscar a few years ago? That had one of the smallest RMW for a Atlantic HU on record and models had no clue!
 

[Windspeed]

Gains in organization got us a TS and some slight increase in inflow and wind, but Edouard needs deeper cells to wrap the nascent core. A moist environment was sampled, but some pesky pockets of stable mid-level air mass may be inhibiting deeper growth. The forecast discussion anticipates convection in the preceding hours to landfall, which could quickly spin up such a tiny vortex. Otherwise, Edouard will have maxed out its potential here. I wouldn't say the system has outperformed yet. I think we suspected the system to get named. With the forecast calling for additional strengthening now, however, I dare say it will underperform if convection doesn't take off prior to landfall. Which I find amusing now, given where we were 24 hours ago.

[NavarreDon]

https://x.com/tropicaltidbits/status/2094626737204466099?s=46&t=0ZvB_AF2VfA6c0SDxf53yA


.

[Scott747]

HAFS-A goes NAM into landfall.

14 mb drop the last 3 hrs....

[WxWatcher007]

Just now, Scott747 said:

HAFS-A goes NAM into landfall.

14 mb drop the last 3 hrs....

I swear I just peeked at it and was going to post. Very interesting. HAFS-B is more muted but gets it close to hurricane strength. 

[Scott747]

4 minutes ago, WxWatcher007 said:

I swear I just peeked at it and was going to post. Very interesting. HAFS-B is more muted but gets it close to hurricane strength. 

If it starts deepening into daybreak then it may be onto something...

[vortex95]

22 minutes ago, Windspeed said:

Gains in organization got us a TS and some slight increase in inflow and wind, but Edouard needs deeper cells to wrap the nascent core. A moist environment was sampled, but some pesky pockets of stable mid-level air mass may be inhibiting deeper growth. The forecast discussion anticipates convection in the preceding hours to landfall, which could quickly spin up such a tiny vortex. Otherwise, Edouard will have maxed out its potential here. I wouldn't say the system has outperformed yet. I think we suspected the system to get named. With the forecast calling for additional strengthening now, however, I dare say it will underperform if convection doesn't take off prior to landfall. Which I find amusing now, given where we were 24 hours ago.

In marginal or so-so conditions, a system can get organized quickly when it comes to a LLCC and the TD/weak TS stage, but true RI going 25-30 kt in 18 hr is a significantly more of a challenge or unsure.

I'd more concerned about RI here if the environment was marginal due to mdt shear and surrounding environment was sufficiently most as that can lead to RI in some cases.  See here:
https://journals.ametsoc.org/view/journals/mwre/146/11/mwr-d-18-0020.1.xml
 

[WxWatcher007]

2 minutes ago, Scott747 said:

If it starts deepening into daybreak then it may be onto something...

Yep. And we’ll see it happening on radar. Homebrew systems are interesting more often than not imo. Here’s another one.

[vortex95]

35 minutes ago, WxWatcher007 said:

I swear I just peeked at it and was going to post. Very interesting. HAFS-B is more muted but gets it close to hurricane strength. 

It appears HAFS-A/B are in error b/c they both show strong convection right over the LLCC 03 and 06z, and this is resulting in feedback.  I attached the fcst hr 3 valid 03z from the HAFS-A/B.  That did not verify. 

Also, the strong N side convective band on sat we see now is not handled well.

So their later fcst hours are questionable. These small differences in initialization when dealing w/ convection and structure can result in large errors.

The HAFS is known to do a great job, but tiny TCs like that are not common, and I don't have a feel for their performance in such cases. 

It is tempting to be impressed by the hires models now, but they can give very realistic and precise-looking output that can be precisely wrong.

No change in in winds or pressure last recon pass 0444z.

So I and hesitant on RI still.  Sometimes, I go to myself, "prove it to me!" that X can happen, and sometimes I am proven wrong!  But I try to not let "just b/c the models say so" or "NHC says this" influence independent judgement and gut in forecasting.  Doing very short-term "what has happened up until now and trends" and what is current -- that I put more weight towards.

Edouard's case is almost like what convection will do during a big svr day fcst, and you know how fickle and uncertain that can be!

[WxWatcher007]

3 minutes ago, vortex95 said:

It appears HAFA-A/B are in error b/c  they both show strong convection right over the LLCC 03 and 06z, and this is resulting in feedback.  I attached the fcst hr 3 valid 03z from the HAFS-A.  That did not verify.

 

Good point. We’ll see if there’s a convective burst over the center in the coming hours. Like your post earlier stated, models are going to struggle forecasting intensity here. The environment as it stands tells us a lot, and we’ll see how close to the ceiling Edouard gets.