Western Caribbean disturabance 94L bringing heavy rains; Lupit's path uncertain

By: Dr. Jeff Masters , 2:39 PM GMT on October 21, 2009

Share this Blog
2
+

A broad 1008 mb low pressure area has developed near 10N 84W, inland over Costa Rica. NHC designated this disturbance Invest 94L yesterday, but is no longer issuing model products for the disturbance. This morning's QuikSCAT pass showed a broad circulation around the low, with top winds of about 30 - 35 mph over the extreme Southwestern Caribbean. Obviously, the center will have to move over water in order for significant development to occur, but recent satellite loops show that the low is pulling in an increasing amount of moisture from the Pacific, leading to heavy rains over Costa Rica and western Panama. Wind shear is low, about 5 - 10 knots, and there is deep layer of high moisture over the entire Western Caribbean, which both favor development if the center moves over water. Rainfall estimates from the Navy Research Lab indicate that 94L dumped up to three inches of rain over portions of Panama, Costa Rica, and Nicaragua over the past 24 hours.


Figure 1. Morning satellite image of Invest 94L.

The forecast for 94L
Wind shear is expected to remain in the low to moderate range, 5 - 15 knots, for the next five days in the Western Caribbean. Sea Surface temperatures are very warm, 29°C, and there is plenty of moisture through a deep layer of the atmosphere. The only major impediment to 94L becoming a tropical storm later this week would seem to be proximity to land. At present, only the GFS model develops 94L, but weeks it very weak. The GFS predicts the storm will take a north then northwesterly track across western Cuba early next week, then into the Gulf Coast of Florida later in the week. However, it is equally likely that 94L will stay bottled up in the Western Caribbean for the foreseeable future. I'll continue to give 94L a medium (30 - 50% chance) of eventually becoming a tropical depression over the next ten days. NHC is giving 94L a low (less than 30% chance) of developing into a tropical depression by Friday, which is a good forecast. Given 94L's current state of disorganization and location over land, Saturday is the earliest we should expect it to organize into a tropical depression. NHC has not put the Hurricane Hunters on call to fly 94L Thursday or Friday.

Rick misses Baja, hits Mainland Mexico near Mazatlan
Tropical Storm Rick made landfall near 10am EDT in Mainland Mexico just north of Mazatlan. Top winds measured at the Matatlan airport during landfall were 39 mph, gusting to 61 mph. The primary threat from Rick will be heavy rains of up to six inches in the mountains near Mazatlan. Rick's remains should being at most one inch of rain to south-central Texas on Thursday.

Typhoon Lupit weakens and slows; path now uncertain
Typhoon Lupit, now a Category 1 storm with 90 mph winds, continues to have difficulty dealing with a slug of dry air it wrapped into its core two days ago. Microwave imagery showed that the typhoon was missing a portion of its northern eyewall this morning. However, recent Infrared satellite loops show that the eye has warmed and become more distinct, a sign of intensification. Also, the cloud tops of Lupit's eyewall have cooled in recent hours, signaling that they are more vigorous and reaching higher into the atmosphere. Lupit is in an environment favorable for re-intensification, with low wind shear of 5 - 10 knots and warm sea surface temperatures of 28 - 29°C. It would not be a surprise to see Lupit intensify into a major Category 3 typhoon again by Thursday, though the official forecast from the Joint Typhoon Warning Center is less aggressive, calling for a Category 2 storm by tomorrow. Even in its current weakened state, Lupit is a prodigious rain-maker, with rainfall rates exceeding one inch per hour near its core (Figure 2).

The future path of the typhoon is now highly uncertain, as steering currents are weakening and the storm is slowing down. A weakness in the ridge of high pressure steering Lupit west-southwest is developing, and several models (ECMWF, GFS) now predict recurvature of the typhoon before it reaches the Philippines. This optimistic scenario is counterbalanced by the very pessimistic forecasts of the UKMET and NOGAPS models, which take the typhoon inland over the northern portion of Luzon 1 - 2 days from now, and then stall the storm for 2 - 3 days. This would cause a major flooding disaster, as the soils are already saturated and the dams completely full from the 20+ inches of rain dumped by Super Typhoon Parma in early October. If Lupit stalls for several days over Luzon, it would dump another 20+ inches of rain, triggering massive flash flooding and life-threatening mudslides.

Storm chased Jim Edds is in northern Luzon to document Lupit's landfall, and has some interesting photos of the preparations the residents are taking.


Figure 2. Rainfall rates observed by a polar-orbiting microwave satellite at at 10:24 UTC Wednesday 10/21/09. Lupit is expected to dump rains in excess of one inch per hour (red and pink colors) along its path. Up to 12 inches of rain in a 24-hour period are expected from the typhoon. Image credit: Navy Research Lab, Monterey..

I'll have an update Thursday morning.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

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: 639 - 589

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21Blog Index

Good Evening...
Member Since: Posts: Comments:
94L been drop the navy site no longer has it up
Member Since: Posts: Comments:
Quoting HURRICANECAT5:
Looks like convection is on the increase and so is vorticity with 94L. Vorticity is alot better organized and this is the most organized convection pattern we have seen with this system.

How do you post an image on the blog?



=====================================================
Look up to the right on this page and see link:

How to start your own blog, and add blog images and links


and then click on:

How do I add an image?


Member Since: Posts: Comments:
Quoting HURRICANECAT5:
Looks like convection is on the increase and so is vorticity with 94L. Vorticity is alot better organized and this is the most organized convection pattern we have seen with this system.

How do you post an image on the blog?
Right click on the image you want to post, go to properties, copy location then you go to iamge where you comment paste the location,enter,enter and then post comment. hope you can understand this. I had a tough time but have learned now.
Member Since: October 9, 2008 Posts: 0 Comments: 8435
635. amd
Quoting Weather456:



I'm not sure you guys using Puerto Limon since the daytime cycle of pressure would of interfere with any reliable pressure patterns when the center came ashore. In addition, I do think the system heights would of fall while over land so the land obs would reveal that very same thing. Further, there are obs closer to the supposed center which supported a gradual decrease in pressure not 24 hrs but 72 hrs, indicating slow development which as been repeated over and over again.

have a good night.


that's a good point, however a word of caution, the center came onshore sometime last night, I think around 9 pm or so.

I have been following the observations around Puerto Limon off and on for the past 2 days, and I think that only report from 7 am edt to 7 pm edt, so I'm not sure that we have an accurate measurement of what the exact pressure was at landfall of the center last night.

Anyway, I do agree with you on the model thing. There is a lack of information in the sw caribbean (lack of buoys, inconsistent weather stations, part time weather stations, wind observations possibly being affected by winds funneling through the mountains of Panama, Nicaragua, etc.), so therefore the models may not have all the proper information to make a correct forecast.
Member Since: Posts: Comments:
Link
Member Since: Posts: Comments:
Looks like convection is on the increase and so is vorticity with 94L. Vorticity is alot better organized and this is the most organized convection pattern we have seen with this system.

How do you post an image on the blog?
Member Since: Posts: Comments:
Much more definitive "spin" now just east of the Nicaraguan coast.
Member Since: Posts: Comments:
Quoting amd:
w456, ike is right in this case.

The pressure at puerto limon also fell to around 1006 mb yesterday in the early afternoon, and then started to rise in the evening.

In fact, I'm pretty sure I made a post yesterday from work stating that the pressure was falling to 1006 mb at Puerto Limon.

It seems to me that it looks like this stuff in the sw caribbean is tied to the ITCZ in the pacific, and also a bahamian system that may try to develop.

Even though a "kink" in the monsoon trough in the SW Caribbean would eventually signal development of a low, land interaction and possible ITCZ action from the pacific may be stopping the moisture from fully consolidating in the SW Caribbean, and forming a low.

Instead, with the new model support in an area with more observations to feed into those models (s.e. bahamas), I wouldn't be surprised to see a hybrid low develop in that region and suck the moisture out of the s.w. Caribbean.

Of course, I could end up being wrong about this, like I was last night and this morning about a system developing in the far east pacific, but it could happen.

All of this is JMHO



I'm not sure why you guys using Puerto Limon since the daytime cycle of pressure would of interfere with any reliable pressure patterns when the center came ashore. In addition, I do not think the system heights would of fall while over land so the land obs would reveal what we want to see. Further, there are obs closer to the supposed center which supported a gradual decrease in pressure not over 24 hrs but 72 hrs, indicating slow development which as been repeated over and over again for the past few days.

have a good night.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
630. amd
w456, ike is right in this case.

The pressure at puerto limon also fell to around 1006 mb yesterday in the early afternoon, and then started to rise in the evening.

In fact, I'm pretty sure I made a post yesterday from work stating that the pressure was falling to 1006 mb at Puerto Limon.

It seems to me that it looks like this stuff in the sw caribbean is tied to the ITCZ in the pacific, and also a bahamian system that may try to develop.

Even though a "kink" in the monsoon trough in the SW Caribbean would eventually signal development of a low, land interaction and possible ITCZ action from the pacific may be stopping the moisture from fully consolidating in the SW Caribbean, and forming a low.

Instead, with the new model support in an area with more observations to feed into those models (s.e. bahamas), I wouldn't be surprised to see a hybrid low develop in that region and suck the moisture out of the s.w. Caribbean.

Of course, I could end up being wrong about this, like I was last night and this morning about a system developing in the far east pacific, but it could happen.

All of this is JMHO.
Member Since: Posts: Comments:
Quoting Weather456:
Im gonna call it a night.

See you guys in the morn.


Night 456, you're doing a great job with this disturbance.
Member Since: July 1, 2008 Posts: 13 Comments: 7423
Quoting Weather456:
Im gonna call it a night.

See you guys in the morn.
Look forward to it. Have a good night.
Member Since: October 9, 2008 Posts: 0 Comments: 8435
Quoting reedzone:
look at the bright side, the downcasters aren't out since it's deactivation.. weird..


We're just lurking b/c we don't feel like getting yelled at.
Member Since: Posts: Comments:
Quoting Weather456:
Im gonna call it a night.

See you guys in the morn.

Have a good one
Member Since: Posts: Comments:
Im gonna call it a night.

See you guys in the morn.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
possible COC 12.5N/83W ?
Member Since: Posts: Comments:
look at the bright side, the downcasters aren't out since it's deactivation.. weird..
Member Since: July 1, 2008 Posts: 13 Comments: 7423
Quoting IKE:


Which is part of the reason it fell earlier in the day....because it was suppose to.


It could be that but cannot explain the 1007 mb low which was 1010 mb.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
621. IKE
Quoting Weather456:


System north of there so if pressures are rising it could be the low is moving away (northward) or it's the diurnal cycle which peaks at 22 Local Time


Which is part of the reason it fell earlier in the day....because it was suppose to.
Member Since: Posts: Comments:
I think the AOI is drifting northward too.
Quoting Weather456:


System north of there so if pressures are rising it could be the low is moving away (northward) or it's the diurnal cycle which peaks at 22 Local Time
Member Since: Posts: Comments:
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting Weather456:


System north of there so if pressures are rising it could be the low is moving away (northward) or it's the diurnal cycle which peaks at 22 Local Time
That's my thinking too as it looks to be E of Nicaragua which is N of Costa Rica.
Member Since: October 9, 2008 Posts: 0 Comments: 8435
Quoting IKE:
The pressure at this location has risen .06 inches of mercury in the last few hours....from a low of 29.69 up to 29.75 now. Location is 10N and 83W....

"Puerto Limon, Costa Rica (Airport)
Updated: 28 min 40 sec ago
Haze
80 °F
Haze
Humidity: 84%
Dew Point: 76 °F
Wind: Calm
Wind Gust: -
Pressure: 29.75 in (Rising)
Visibility: 9.0 miles
UV: 0 out of 16
Clouds:
Mostly Cloudy 1476 ft
(Above Ground Level)
Elevation: 16 ft"


System north of there so if pressures are rising it could be the low is moving away (northward) or it's the diurnal cycle which peaks at 22 Local Time
Member Since: July 24, 2005 Posts: 407 Comments: 19076
San Andres, CO (Airport)
Updated: 32 min 30 sec ago 25 C
Mostly Cloudy
Humidity: 89%
Dew Point: 23 C
Wind: Calm

Pressure: 1007 hPa (Rising)
Visibility: 10.0 kilometers
UV: 0 out of 16
Clouds: Few 304 m
Mostly Cloudy 2133 m
(Above Ground Level)
Elevation: 2 m
Rapid Fire Updates:
Enable Disable


Member Since: Posts: Comments:
Quoting Weather456:
How is it an argument without being informative if both sides of the debate are presenting their reasons? That seems like an informative debate or argument as some referred it.


because people are seeing what they want to see. it was the same thing with the few 'Canes that were wandering around in the Atlantic this summer.

maybe I'm just more annoyed than I usually would be because I'm in Florida a week from today (east coast thankfully, that Bahama thing should be outta there by then, hopefully it doesn't come ashore and screw up my drive) and I find this system a pain in the butt.

not so much for the potential for a huge storm, but hoping this doesn't turn into one of those monsoonal tropical storms with not too much wind, but plenty of rain.
Member Since: Posts: Comments:
613. IKE
The pressure at this location has risen .06 inches of mercury in the last few hours....from a low of 29.69 up to 29.75 now. Location is 10N and 83W....

"Puerto Limon, Costa Rica (Airport)
Updated: 28 min 40 sec ago
Haze
80 °F
Haze
Humidity: 84%
Dew Point: 76 °F
Wind: Calm
Wind Gust: -
Pressure: 29.75 in (Rising)
Visibility: 9.0 miles
UV: 0 out of 16
Clouds:
Mostly Cloudy 1476 ft
(Above Ground Level)
Elevation: 16 ft"
Member Since: Posts: Comments:
I don't write off anything that has persisted this long in that area this time of year, it is becoming more consolidated & slightly better organized this evening imo.
Member Since: Posts: Comments:
Quoting Weather456:
How is it an argument without being informative if both sides of the debate are presenting their reasons? That seems like an informative debate or argument as some referred it.
Yes. You are right.
Member Since: October 9, 2008 Posts: 0 Comments: 8435
Quoting njdevil:


yeah, it's pretty lame, two camps of know-it-alls arguing with each other without being very informative.

some of the people that are harping on this were the same people trying to run storms into NYC this summer when the guidance was 200 miles + east.
I know NJDevil- you take the good with the bad and make the best of it. But at certain times one must have a tolerant, easy going attitude or the trolls will get under your skin.
Member Since: September 27, 2007 Posts: 1 Comments: 21865
How is it an argument without being informative if both sides of the debate are presenting their reasons? That seems like an informative debate or argument as some referred it.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting centralflaman:
This blog cracks me up!

It is also pretty well known that models do horrible with systems in this area especially this time of year. Tropical systems are notorious for popping up pretty quickly down there without model support. I think it is pretty safe to say we will not know what is going to happen until this weekend. Also just because a invest has been dropped means nothing. If I remember correctly Katrina was an invest and then designated again later as a different storm before hitting Florida.


Really? I feel the opposite. This time of year systems can fester for a good 7 days before coming together. I also feel models do poorly with slowly developing systems. They only do well with well defined systems that are coming together quickly.

*shrugs*

***********************************************I agree with you. That is what I meant just worded wrong. Systems form down there without model support pretty frequently.
Member Since: Posts: Comments:
Quoting P451:


Really? I feel the opposite. This time of year systems can fester for a good 7 days before coming together. I also feel models do poorly with slowly developing systems. They only do well with well defined systems that are coming together quickly.

*shrugs*

Notice he said pop up quickly without model support.Didn't say they pop up quickly. I agree they fester for days but I think he only meant without model support. Too much emphasis on the models and not enough on what is actually happening.
Member Since: October 9, 2008 Posts: 0 Comments: 8435
Quoting Detrina:
Wow, this place used to be so helpful and informational. Now it's *mostly* just a bunch of bickering back and forth, is it just because there has been no impending doom for a couple of years or what?

I'm glad for the lack of impending doom, but sad for the state of the blog:(


yeah, it's pretty lame, two camps of know-it-alls arguing with each other without being very informative.

some of the people that are harping on this were the same people trying to run storms into NYC this summer when the guidance was 200 miles + east.
Member Since: Posts: Comments:
Quoting Detrina:
Wow, this place used to be so helpful and informational. Now it's *mostly* just a bunch of bickering back and forth, is it just because there has been no impending doom for a couple of years or what?

I'm glad for the lack of impending doom, but sad for the state of the blog:(

This place has become discombobulated over this un-predictable headache giving season... our only certainty this season has been the uncertain...
Member Since: Posts: Comments:
Quoting Skyepony:
I'm suprised keys NWS was discounting the 12Z gfs & low trying to form in the Bahamas & move up the east side of FL. CMC has been on it for like 3 days, gfs 2 days & it gets stronger each run. It's not like it just showed up on the 12z run..
The NAM actually pegged the Bahamas low 3 days ago.
Member Since: September 27, 2007 Posts: 1 Comments: 21865
602. beell
Quoting Skyepony:
I'm suprised keys NWS was discounting the 12Z gfs & low trying to form in the Bahamas & move up the east side of FL. CMC has been on it for like 3 days, gfs 2 days & it gets stronger each run. It's not like it just showed up on the 12z run..


Maybe so, Skye,
That feature looks to form at the other (north) end of the surface trough where it intersects the remains of the last frontal boundary. The other low on the S end in the Caribbean.
Member Since: Posts: Comments:
This blog cracks me up!

It is also pretty well known that models do horrible with systems in this area especially this time of year. Tropical systems are notorious for popping up pretty quickly down there without model support. I think it is pretty safe to say we will not know what is going to happen until this weekend. Also just because a invest has been dropped means nothing. If I remember correctly Katrina was an invest and then designated again later as a different storm before hitting Florida.
Member Since: Posts: Comments:
Infrared imagery shows consolidation of convection

Member Since: July 24, 2005 Posts: 407 Comments: 19076
good evening guys
Member Since: Posts: Comments:
Convection looks to be consolidating in the area that Weather456, Kman and Drakoen placed it this afternoon. I for one am watching it closely.
Member Since: October 9, 2008 Posts: 0 Comments: 8435
Member Since: July 24, 2005 Posts: 407 Comments: 19076
596. Skyepony (Mod)
I'm suprised keys NWS was discounting the 12Z gfs & low trying to form in the Bahamas & move up the east side of FL. CMC has been on it for like 3 days, gfs 2 days & it gets stronger each run. It's not like it just showed up on the 12z run..
Member Since: August 10, 2005 Posts: 196 Comments: 38772
Quoting Dakster:
I actually find this amusing. It is isn't even named yet (ex94L) and it is already starting to pull tricks... Just like the rest of the season.
Yes Dak, Earlier we were talking about multiple vortexes (haha). We had some of those this season.
Member Since: September 27, 2007 Posts: 1 Comments: 21865
594. beell
It's pretty simple. If you sift through all the runs of the GFS and the Euro over the last three or four days you should come away with a common thread:

A surface low S of Cuba Saturday/Sunday in warm water with improving upper level winds and weak steering. Waiting on a somewhat weak cold front to carry it on its way.

We have been pretty lucky this year. Not a time to be complacent. If anything does form I think it will not be too strong-but this is one you have to watch.

NHC may give it 30% but I'll give at least a 50% chance that I don't know what will happen.
Member Since: Posts: Comments:
Wow, this place used to be so helpful and informational. Now it's *mostly* just a bunch of bickering back and forth, is it just because there has been no impending doom for a couple of years or what?

I'm glad for the lack of impending doom, but sad for the state of the blog:(
Member Since: Posts: Comments:
Quoting Txwxchaser:
Why don't we all just sit back and relax for now. If...I said "if" and when real organization does take place...we can then let the experience on this site work their magic and watch the "real" debates begin....Now that's what I'm waiting for.....this is like watching paint dry for Pete's sake!!!
well said.
Member Since: September 27, 2007 Posts: 1 Comments: 21865
Post 585 and 586

I think it's peculiar how some on here discount the models when they don't show much(referencing 94L)....

But...those same posters didn't discount the models when they showed a system(94L) developing.


I dont understand...

You have been doing that all season (just the other way around) and it have some people here like Kman, Drak, SW and myself who can tell when a model is being inconsistent and we give clear, concise and valid reasons, not post the NWS discussions. We have seen models develop a storm and discount it, like 95L and 98L and many other ghost storms we have seen this year. So that statement is not all true.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting IKE:


Exactly...

I had this comment typed out, but hadn't posted it yet....

I think it's peculiar how some on here discount the models when they don't show much(referencing 94L)....

But...those same posters didn't discount the models when they showed a system(94L) developing.
Exactly Ike not saying it's a given yes something could develop, but think some bloggers are having Near Hurricane Season End withdrawal symptoms think the fat lady is tuning up for her final song
Member Since: Posts: Comments:
I actually find this amusing. It is isn't even named yet (ex94L) and it is already starting to pull tricks... Just like the rest of the season.
Member Since: Posts: Comments:

Viewing: 639 - 589

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21Blog 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.

Local Weather

Light Rain
42 °F
Light Rain