Dr. Jeff Masters' WunderBlog

Quoting btwntx08:

but now i agree with u on the near 30 kts shear on 97L and it is still to watch after it gets though the shear so its just wait and see game for a couple of days

Honestly the shear was 15kts the other nite.....out of the NW.....if you would have zoomed in you could see the cloud tops blowing off.......5kts of shear does not cause that.....Yes it still bears some watching but, not much....LOOK East and watch the GOM and off the Atlantic seaboard the next few days.

Quoting TampaSpin:
Just looked at Data.....97L is vertually dead....it will be poof in 12hrs.....Shear will be ripping it apart!

You said the same thing last night.

I'm sorry to rain on some people's parade. But 97L is about to head into 40 Knots of Vertical Wind Shear. You can already see the shear's effect on satellite. Also, to the people denying Tampaspin you shouldn't be, He has been right all along with 97L. So quit saying he is wrong and wishcasting because you are only putting whatever you think your reputation is here in jeopardy.

Some of y'all need to relax and look at a WV Loop and have fun on here and learn. That's what needs to happen here. But I can't force some of you to do it.

Wxman504

Quoting moonlightcowboy:
97L is finally showing some lower level convergence as well.

very true

SOI still positive

The divergence is also increasing

It can still make it, TS - maybe not tomorrow, but maybe past the islands if it can keep some circulation intact...it's doing that so far. With some low level convergence it may be able to keep creating some good lift through dmax to maintain its spin and convection, despite the shear blowing tops off. There is no shear with 97L at the mid-levels. Additionally, the anti-cyclone is growing off the northern SA coast into the Caribbean.

Convection is converging and exploding. It's defying the shear, but for how long.

Quoting CybrTeddy:


Wow Tampa, serious whats your problem this year? Calling wishcasters, insulting people, ect. You weren't anything like that last year.

Cybr know you for a long time......if i came across that to everyone i apologize...it was only intended to just a hand full..

Quoting moonlightcowboy:
It can still make it, TS - maybe not tomorrow, but maybe past the islands if it can keep some circulation intact...it's doing that so far. With some low level convergence it may be able to keep creating some good lift through dmax to maintain its spin and convection, despite the shear blowing tops off. There is no shear with 97L at the mid-levels. Additionally, the anti-cyclone is growing off the northern SA coast into the Caribbean.

agree

97L is like the brave little toaster!! Haha, holding out against shear. Is it me or is there more of a noticeable WNW component right now, or is it the mess of convection messing with my eyes?

Pressure (MSLP): 1011 mb (29.85 inHg | 1011 hPa)
Sustained wind speed (1 min. avg.): 25 knots (29 mph | 13 m/s)

Quoting Relix:
97L is like the brave little toaster!! Haha, holding out against shear. Is it me or is there more of a noticeable WNW component right now, or is it the mess of convection messing with my eyes?

It could be the convection expanding

Quoting Relix:
97L is like the brave little toaster!! Haha, holding out against shear. Is it me or is there more of a noticeable WNW component right now, or is it the mess of convection messing with my eyes?

I think it's an illusion from the upper level shear blowing the tops off 97L. I believe it's still holding basically true to the westerly steering patterns. And, unless mine are deceiving me, there may actually be a small swesterly movement.

Quoting Funkadelic:


You do have to admit pressure is falling and getting convection again... Maybe 97l won't be destroyed after all

10% chance maybe....I don't see it making it.

Pressure dropping at a buoy just east of the invest:
Wind Direction (WDIR): E ( 80 deg true )
5-day plot - Wind Speed Wind Speed (WSPD): 19.4 kts
5-day plot - Wind Gust Wind Gust (GST): 23.3 kts
5-day plot - Wave Height Wave Height (WVHT): 9.2 ft
5-day plot - Dominant Wave Period Dominant Wave Period (DPD): 8 sec
5-day plot - Average Period Average Period (APD): 5.8 sec
5-day plot - Atmospheric Pressure Atmospheric Pressure (PRES): 29.91 in
5-day plot - Pressure Tendency Pressure Tendency (PTDY): -0.05 in ( Falling )
5-day plot - Air Temperature Air Temperature (ATMP): 81.3 °F
5-day plot - Water Temperature Water Temperature (WTMP): 81.9 °F
5-day plot - Dew Point Dew Point (DEWP): 76.8 °F
5-day plot - Heat Index Heat Index (HEAT): 88.5 °F

Buoy to the west also reporting falling pressure:
Wind Direction (WDIR): E ( 80 deg true )
24-hour plot - Wind Speed Wind Speed (WSPD): 22.0 kts
24-hour plot - Wave Height Wave Height (WVHT): 7.2 ft
24-hour plot - Dominant Wave Period Dominant Wave Period (DPD): 8 sec
24-hour plot - Atmospheric Pressure Atmospheric Pressure (PRES): 29.90 in
24-hour plot - Pressure Tendency Pressure Tendency (PTDY): -0.05 in ( Falling )
24-hour plot - Air Temperature Air Temperature (ATMP): 81.7 °F
24-hour plot - Water Temperature Water Temperature (WTMP): 81.5 °F
24-hour plot - Dew Point Dew Point (DEWP): 75.7 °F
24-hour plot - Heat Index Heat Index (HEAT): 88.5 °F

the shear doesnt look as bad

The ULL to the North is causing alot of the Shear.....it too is moving nearly due West and might start moving more WSW......Shear won't be relaxing anytime in the next couple of days.

Quoting TampaSpin:


Cybr know you for a long time......if i came across that to everyone i apologize...it was only intended to just a hand full..

I know man, its not your forecasting though thats off (pretty darn accurate) its the little end comments that tend to well.. rall up the blog.

Couldnt sleep and finished my book. :( The CMC takes this smack into central Louisiana. Yea I know, I know. IF it survives, too early, etc. Just found that a little too close for comfort.

Looks to be trying to fire some heavy convection

Approaching Dmax.

The other little guy at 30W flaring up pretty good too.

Quoting homelesswanderer:
The other little guy at 30W flaring up pretty good too.

Quoting FloridaTigers:
Approaching Dmax.

Yes to both of these

Has some SAL to get through

looks to me like a big part of the convection flare up is more from DMAX and divergence created by the ULL that anything else.

Quoting SouthALWX:
looks to me like a big part of the convection flare up is more from DMAX and divergence created by the ULL that anything else.

That's the whole point of DMAX. To flare up and there is also improved convergence. It's taking advantage of DMAX.

Quoting weatherwatcher12:

That's the whole point of DMAX. To flare up and there is also improved convergence

The flare up is from the ULL causing uplift...

Yeah it does have to get through the SAL. I don't know if either of these will survive. But if this is any indication of what the actual CV season will be like I think it may be a lot busier than people think. This is my first season tracking the storms. But the SOI looks like its not doing what was expected of it either.

Have to disagree, convergence may be increasing but if you look at the divergent upper air pattern it's clear to see the culprit is the ULL. Reminds of a month or so ago when divergent upper flow created a "blob" that was talked about on here for two nights ... Once the divergence shut down so did the blob .I think it was over haiti for a few days you guys may remember I don't remember who but there was a detailed explanation concerning the divergent factors given that I found to be spot on.. Nothing to really look at now imo until a few days out when 97 emerges (if) in the western to central carribean.

Agree with TS on this, though dmax will play a role, this is a case of divergence.

Quoting SouthALWX:
Have to disagree, convergence may be increasing but if you look at the divergent upper air pattern it's clear to see the culprit is the ULL. Reminds of a month or so ago when divergent upper flow created a "blob" that was talked about on here for two nights ... Once the divergence shut down so did the blob ... Nothing to really look at now imo until a few days out when 97 emerges (if) in the western to central carribean.

Dido.....well said!

Quoting SouthALWX:
Have to disagree, convergence may be increasing but if you look at the divergent upper air pattern it's clear to see the culprit is the ULL. Reminds of a month or so ago when divergent upper flow created a "blob" that was talked about on here for two nights ... Once the divergence shut down so did the blob ... Nothing to really look at now imo until a few days out when 97 emerges (if) in the western to central carribean.

Even if the convection is just ULL there is still a high 850mb vorticity associated with it.

Quoting weatherwatcher12:

Even if the convection is just ULL there is still a high 850mb vorticity associated with it.

So if it can detach itself from the divergence and fire it's own convection it has a fair chance.

Quoting weatherwatcher12:

Even if the convection is just ULL there is still a high 850mb vorticity associated with it.

correct, and that vorticity is what will be watched in the carribean should it be maintained to any extent.

I think I see what could be an anti-cyclone forming in the central Caribbean

a key here is to follow the shape of convection .. it's following the divergence as it fans out forming a left facing "V" shape.

India Meteorological Department
Tropical Cyclone Bulletin Number ONE
DEPRESSION BOB03-2009
8:30 AM IST July 20 2009
=====================================

Sub: Depression over northwest Bay of Bengal

At 3:00 AM UTC, Latest satellite imageries and coastal observation indicate that a depression has formed over northwest Bay of Bengal and lays centered near 21.0N 88.5E or about 120 kms southeast of Digha, 160 kms east-southeast of Balasore, and 200 kms southwest of Khepupara.

Satellite imagery indicates gradual organization of convection during past 12 hours. The Dvorak intensity of the system is T1.5. Associated broken intense to very intense convection lies over Bay of Bengal between 18.5N and 21.5N and to the west of 89.5E. The lowest cloud top temperature due to convection is around -70C.

Maximum 3 minute sustained winds near the center is 25 knots with a central pressure of 992 hPa. The state of the sea is rough to very rough around the system's center.

Vertical wind shear of horizontal wind over the region is low to moderate (around 10-20 knots). Sea surface temperature is about 29C. The system is supported by upper level divergence and lower level convergence. Strong east-southeasterly winds prevail over the region in the upper tropospheric level. As observed at 3:00am UTC, the 24 hours pressure fall is higher in the west-northwesterly direction and is maximum (-3.6 hPa) over Digha.

Considering all the above, the system is likely to intensify further and move in a west-northwesterly direction and cross north Orissa-West Bengal coast between Balasore and Digha around 1200 PM UTC.

well im out guys, we'll know more of 97s future very soon no reason to jump to RIP/apoco-cane yet =] Vorticity is consolidated and I've seen waves survive worse so we'll see. Of course I've seen waves die in what seemed perfect conditions too. It remains to be seen, what we do know is that the convection tonight is of little consequence to 97's future. I could be wrong, but that's my take =]

New shear map. Any thoughts.

Another view. On this it doesn't appear to be pulling to the north.

Link

Quoting weatherwatcher12:
New shear map. Any thoughts.

NO surprises.....you can see the shear increasing the past 24hours.....i won't change too much the next 24 either.

Look the divergence flow has been cut off from the ULL

The convergence has increased too

Quoting weatherwatcher12:
The convergence has increased too

The increase in convergence is likely diurnal.