92L very disorganized, but a long-range threat to develop

By: Dr. Jeff Masters , 2:05 PM GMT on June 18, 2010

Share this Blog
2
+

Invest 92L, which yesterday became severely disrupted by wind shear and dry air, is generating a large area of rain showers over the northern Lesser Antilles Islands today. Infrared satellite loops show that the tops of the thunderstorms associated with 92L have warmed in recent hours, and these thunderstorms are weak and disorganized. Water vapor satellite loops show that there is a large amount of dry air in the storm's environment, and this dry air is getting sucked into 92L's thunderstorms, where the dry air is sinking to the surface and creating surface "arc clouds"--arc-shaped clouds that spread out away from 92L's thunderstorms. With wind shear at 20 - 30 knots today, no signs of a surface circulation, and plenty of dry air around, 92L is not a threat to develop into a tropical depression today or Saturday. The National Hurricane Center is giving 92L a low (20% chance) of developing into a tropical depression by Sunday morning. I put the chances at 1%. You can track the progress of 92L today by looking at our wundermap for the region, with weather stations turned on. Antigua recorded sustaiined winds of 20 mph this morning from 92L.

A slight chance 92L could develop next week
Today and Saturday, 92L will encounter 20 - 40 knots of wind shear as it plows though a region of strong upper-level winds associated with the subtropical jet stream. The disturbance will also encounter the mountainous terrain of Hispaniola. These factors should significantly disrupt the disturbance. If there's anything left of 92L by Sunday, when it will be over eastern Cuba, the storm may have the opportunity to develop. At that time, 92L will have passed through the core of the subtropical jet stream and entered a region of lower shear (15 - 20 knots.) For the latest round of 00Z and 06Z model runs, the HWRF is the only reliable model calling for 92L to develop; that model predicts that 92L will organize into a tropical depression on Wednesday over the Lower Florida Keys, and head into the Gulf of Mexico. The obstacles that 92L must overcome to do this are great, and I give 92L just a 10% chance of eventually developing into a tropical depression by Wednesday next week.


Figure 1. Morning satellite image of Invest 92L. Dry air is getting sucked into 92L's thunderstorms, where the more dense dry air creates downdrafts. When these downdrafts hit the surface, the air spreads out creating surface "arc clouds"--arc-shaped clouds that spread out away from 92L's thunderstorms. This puts stable air into the storm's low level environment and blocks inflow of moist air into the core of the storm, weakening it. These arc clouds are a telltale sign that dry air is significantly disrupting the disturbance.

Elsewhere in the tropics
The NOGAPS model is calling for a tropical disturbance to form off the coast of Nicaragua on Monday and push ashore over that country on Tuesday, bringing heavy rains.

Wind and ocean current forecast for the BP oil disaster
Light and variable winds less than 10 knots will blow in the northern Gulf of Mexico for the next five days, according to the latest marine forecast from NOAA. The winds will tend to have a westerly component through Saturday, which will maintain a threat of oil hitting beaches as far east as Panama City, Florida, according to the latest trajectory forecasts from NOAA and the State of Louisiana. Ocean current forecasts for early next week show a weakening of the eastward-flowing currents along the Florida Panhandle, which would limit the eastward movement of oil so that it would not move past Panama City. The long range 8 - 16 day forecast from the GFS model indicates a typical summertime light wind regime, with winds mostly blowing out of the south or southeast. This wind regime will likely keep oil close to the coastal areas that have already seen oil impacts over the past two weeks.

Resources for the BP oil disaster
My post, What a hurricane would do the Deepwater Horizon oil spill
My post on the Southwest Florida "Forbidden Zone" where surface oil will rarely go
My post on what oil might do to a hurricane
NOAA's new interactive mapping tool allows one to overlay wind and ocean current forecasts, oil locations, etc.
Gulf Oil Blog from the UGA Department of Marine Sciences
Oil Spill Academic Task Force
University of South Florida Ocean Circulation Group oil spill forecasts
ROFFS Deepwater Horizon page
Synthetic Aperture Radar (SAR) imagery from the University of Miami

I'll have an update on Saturday.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

Sign In or Register Sign In or Register

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 2206 - 2156

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51Blog Index

2206. KEEPEROFTHEGATE (Mod)
Member Since: Posts: Comments:
AL 92 2010061912 BEST 0 171N 670W 25 1012 WV


Still classified as a wave
Member Since: September 23, 2005 Posts: 15 Comments: 11416
2204. Grothar
Quoting cg2916:


The GFS shear model shows shear lifting over the weekend.


Thanks, cg, and thanks for the concise explanations you give. I tend to be a little verbose sometimes.
Member Since: Posts: Comments:


AOI

AOI

AOI

AOI

TS BUSTED FORECAST ALIBI
Member Since: Posts: Comments:
the tutt over cuba is suppose to split.one half retrograding to the sw and the other to the ne. this may provide some vetilation.nearly all the models show some type of development of 92l.how strong the high that builds into the gom will likely determine the track. even if it's a td,,,the media will have a field day.
Member Since: Posts: Comments:
Good Morning....

Member Since: July 12, 2007 Posts: 0 Comments: 6069
Quoting Grothar:


Notice how any exotic food, one will tell you it tastes like chicken? Thanks for the offer, but I'll pass. LOL My general rule is, never eat anything that looks like it wants to eat you first. kman, is probably correct about the 70W.

Does anyone have a forecast steering map, similar to the one kman posted? I can't seem to find one beyond 24 hours.


Take a look at this site. Steering and more

PSU ewall
Member Since: Posts: Comments:
2199. Grothar
Quoting stormwatcherCI:
Meaning ?


Probably the high shear is knocking off the highest cloud tops. But this system has gone up and down for days. It flares and calms down, it flares and then calms down; much like Mrs. Grothar.
Member Since: Posts: Comments:
2198. IKE
All of that convection has to go by Haiti.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
2197. cg2916
Quoting Grothar:


Yes, it is and seems to be headed into even stronger shear. However, the shear tendency map shows a slightly better condition in 24 hours.



The GFS shear model shows shear lifting over the weekend.
Member Since: Posts: Comments:
Quoting cg2916:


It's slowly losing convection.
Thanks.
Member Since: Posts: Comments:
2195. cg2916
Quoting stormwatcherCI:
Meaning ?


It's slowly losing convection.
Member Since: Posts: Comments:
2194. Grothar
Quoting cg2916:
I am honestly surprised with 92L It is under 30-40 knots shear and still chugging. We'll have to monitor it once it gets out of shear.


Yes, it is and seems to be headed into even stronger shear. However, the shear tendency map shows a slightly better condition in 24 hours.

Member Since: Posts: Comments:
Quoting Grothar:
The central high clouds seem to be shrinking quite a bit in the last few frames.

Meaning ?
Member Since: Posts: Comments:
2191. cg2916
Quoting Grothar:
The central high clouds seem to be shrinking quite a bit in the last few frames.



It did the same yesterday. The MCC gave it enough life to probably last the day.
Member Since: Posts: Comments:
2190. cg2916
Quoting MahFL:
When, if, is the shear supposed to drop ahead of 92L ?


Over the weekend.
Member Since: Posts: Comments:
2189. Grothar
The central high clouds seem to be shrinking quite a bit in the last few frames.

Member Since: Posts: Comments:
ECMWF still trying to develop 92L once it gets into the western Caribbean, then it takes into the Gulf as a weak hurricane. GFS doesn't develop it though.
Member Since: Posts: Comments:
2187. MahFL
When, if, is the shear supposed to drop ahead of 92L ?
Member Since: Posts: Comments:
2186. Grothar
Quoting stormwatcherCI:
Well, we have an over-abundance of green iguanas now so I can offer you that instead of crow. They say it tastes like chicken. LOL kmanislander was on earlier and said it seems to be doing exactly what he thought it would. Also said he thinks it stands a chance around 70W.


Notice how any exotic food, one will tell you it tastes like chicken? Thanks for the offer, but I'll pass. LOL My general rule is, never eat anything that looks like it wants to eat you first. kman, is probably correct about the 70W.

Does anyone have a forecast steering map, similar to the one kman posted? I can't seem to find one beyond 24 hours.
Member Since: Posts: Comments:
2185. cg2916
I am honestly surprised with 92L It is under 30-40 knots shear and still chugging. We'll have to monitor it once it gets out of shear.
Member Since: Posts: Comments:
2184. cg2916
Quoting Weather456:
Hey guys, just came out the hospital last night, will have an update soon enough. Morning btw.


Hospital? Ooh, what happened?

We were all worrying about you. At least every hours people would say "I miss 456's input."
Member Since: Posts: Comments:
Looks like the energy is centered on the southern model (BAMS).


Member Since: Posts: Comments:
Morning all. 92L has sure been interesting.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
If you wish to track 92L's venture west on radar I have links to radars from Pureto Rico, Dominican Republic, Cuba, and more at this site. You can also find more great links for tracking the tropics there as well. Hope it helps :~)
Member Since: Posts: Comments:
Vorticity
Member Since: Posts: Comments:
no such thing as 1/2 circ
Member Since: Posts: Comments:
Quoting Grothar:


Thanks, storm, but please don't compliment me, I only have one good arm left. LOL

Of those who were on here last night, remember that all the large flare-up was to to Northeast of the Islands, but actually, StormW, Levi, kmansislander, and a few others mentioned the shear was very high to the North, so I deduced that any regeneration would occur closer to the center. Can't really take credit for it. It is much better eating cookies, than eating crow.
Well, we have an over-abundance of green iguanas now so I can offer you that instead of crow. They say it tastes like chicken. LOL kmanislander was on earlier and said it seems to be doing exactly what he thought it would. Also said he thinks it stands a chance around 70W.
Member Since: Posts: Comments:
Quoting IKE:
Circulation is better defined today vs. yesterday.


456 and 92L. Better the former than the latter.
Member Since: Posts: Comments:
Im slightly concerned that there are already areas in the Mediterranean sea and Black sea that can suport tropical cyclones.




Member Since: Posts: Comments:
Good morning, looks to the eye like 92L just broke off from its booster and is entering Caribbean.
FloaterLoop


Member Since: Posts: Comments:
RIP 92L "poof"
Member Since: Posts: Comments:
2170. Grothar
Quoting stormwatcherCI:
Kudos to you. Good call. Shear seems to be relaxing to a certain extent across the central Caribbean.


Thanks, storm, but please don't compliment me, I only have one good arm left. LOL

Of those who were on here last night, remember that all the large flare-up was to to Northeast of the Islands, but actually, StormW, Levi, kmansislander, and a few others mentioned the shear was very high to the North, so I deduced that any regeneration would occur closer to the center. Can't really take credit for it. It is much better eating cookies, than eating crow.
Member Since: Posts: Comments:
The E-pac is just firing them off I think the wave coming off central America will develop next
Member Since: Posts: Comments:
Quoting miamiamiga:
Thanks RecordSeason. Still not seeing it, but that does not mean it is not there! I am looking at the radar, and it does not seem the rain pattern is circulating. is that because the circulation is so broad that it is not showing up on radar? It just seems a disorganized mess to me...


That's what happens when you have such strong levels of shear. It is a disorganized mess.
Member Since: Posts: Comments:
Thanks RecordSeason. Still not seeing it, but that does not mean it is not there! I am looking at the radar, and it does not seem the rain pattern is circulating. is that because the circulation is so broad that it is not showing up on radar? It just seems a disorganized mess to me...
Member Since: Posts: Comments:
Quoting Grothar:
Grothar quoting Grothar: from post 1079 last night: (the height of conceit to do that, LOL)

If there is another burst tonight, like last night, it would have to be closer to 64W and 16N. The shear still appears a little strong to the North of the system. The Eastern Caribbean is not really a good area for development if I remember correctly.

First time I got something right in two years. Twisted my neck patting myself on the back. Let us pray it doesn't go near Haiti, though.

Kudos to you. Good call. Shear seems to be relaxing to a certain extent across the central Caribbean.
Member Since: Posts: Comments:
2164. Grothar
Grothar quoting Grothar: from post 1079 last night: (the height of conceit to do that, LOL)

If there is another burst tonight, like last night, it would have to be closer to 64W and 16N. The shear still appears a little strong to the North of the system. The Eastern Caribbean is not really a good area for development if I remember correctly.

First time I got something right in two years. Twisted my neck patting myself on the back. Let us pray it doesn't go near Haiti, though.

Member Since: Posts: Comments:
ASCAT hit it dead on last pass and showed no low level circulation
Member Since: Posts: Comments:
Welcome back 456, glad you are feeling better.... back to lurking!
Member Since: Posts: Comments:
2159. Becca36
Quoting Weather456:
92L maintained a very vigorous mid-level circulation by watching the visible images this morning. It rained very heavy across the islands since about Thursday. Lots of lightning and thunder, but I was too sick to know what was actually going on until this morning.

I'm glad you're out and sorry to hear you were so sick. You've been missed!
Member Since: Posts: Comments:
We are just getting heavy rains and a few thunderstorms here in the Virgins.

Looks like the Mid Atlantic Ridge is going to relax on the west side which will allow 92L to go to FL with the Apex( that would be the top part of that curve W456 just posted) going ashore about Melbourne. There a chance it will follow the east coast if not it will cross FL and follow the gulf coast until absorbed by a Low over the US. Might flare up around the T&C and Bahamas. Either way I don't think it will cause any real problems.

The one to watch for is the wave at 12N 40W. As the MAR relaxes it going to enter the southern Caribbean where there is real Heat content. If there is not to much shear it will blow up quickly. Taz pointed this out as well I think.
Member Since: Posts: Comments:
2157. jpsb
Quoting Weather456:
Hey guys, just came out the hospital last night, will have an update soon enough. Morning btw.
Welcome back!
Member Since: Posts: Comments:

Viewing: 2206 - 2156

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

JeffMasters's Recent Photos

Carrot Nose in Danger
Deep Snow in Brookline, MA
Sunset at Fort DeSoto
New Years Day Sunset in Death Valley