Dr. Jeff Masters' WunderBlog

Tropical Storm Erika likely soon; a weaker Jimena powers towards Baja

Posted by: Dr. Jeff Masters, 07:48 PM GMT del 01 Settembre 2009

Hurricane Jimena has weakened to a low-end Category 4 hurricane with 135 mph winds, thanks to the collapse of its inner eyewall. The hurricane is undergoing a process common in intense hurricanes called an Eyewall Replacement Cycle (ERC), where the eye shrinks to a size too small to be stable, resulting in the disintegration of the eyewall, and the formation of a new eyewall from one of the outer spiral bands. Once the new eyewall becomes stable tonight, Jimena has an opportunity to re-strengthen.

The latest set of 12Z model runs show little change in Jimena's track. The hurricane is still expected to make landfall Wednesday along Mexico's Baja Peninsula. If the hurricane makes landfall over the southern portion of Baja, it would likely be at major hurricane strength. However, SSTs cool quickly to 23°C at the middle of the Baja Peninsula, and Jimena would likely weaken to a Category 2 or 1 hurricane if it makes a strike towards the middle of Baja. The computer models are split on what might happen once Jimena makes landfall on Baja, with one camp predicting a northeast turn bringing the storm over Mainland Mexico and eventually into Arizona, and the other camp stalling Jimena out over or just west of Baja. Regardless, the main threat from Jimena will be flooding and mudslides due to heavy rains.

Baja's hurricane history
The most powerful hurricane on record to hit the west coast of Baja occurred last year, when Hurricane Norbert made landfall on the central Baja coast with sustained winds of 105 mph (Category 2) . Norbert's central pressure of 956 mb at landfall made it the 3rd strongest hurricane to hit the Pacific coast of Mexico since record keeping began in 1949. Norbert killed eight, knocked out power to 20,000 homes, and damaged or destroyed 40% of the homes on the islands of Margarita and Magdalena. Norbert crossed the Baja Peninsula and made landfall on Mainland Mexico as a Category 1 hurricane with 85 mph winds.

Only two major hurricanes have made landfall on Baja since record keeping began in 1949. Both hurricanes hit the east (Gulf of California) side of Baja. The first was Hurricane Olivia of 1967. Olivia made landfall on October 13, 1967 as a Category 3 hurricane with 125 mph winds. Due to its small size and the unpopulated region of coast it hit, damage was minimal. The second major hurricane was Hurricane Kiko, which made landfall on August 27, 1989, as a Category 3 hurricane with winds of 115 mph (minimal Category 3). Kiko was a small hurricane and hit a relatively unpopulated area, resulting in no loss of life and only scattered reports of damage.

Figure 1. A plot of all the major hurricanes to pass within 200 miles of Mexico's Baja Peninsula since 1949. Image credit: NOAA Coastal Services Center.

Invest 94L almost Tropical Storm Erika
The Air Force Hurricane Hunters are investigating tropical wave 94L, about 200 miles east of the Lesser Antilles Islands. So far this afternoon, they have found a broad circulation with top winds of 45 - 50 mph in heavy thunderstorms on the east side. The circulation may be too broad for 94L to be considered a tropical storm, but visible satellite imagery shows that the circulation is getting better defined, and 94L's heavy thunderstorms are moving closer to the center of circulation. Recent satellite wind shear analyses by NOAA/Colorado State University and the University of Wisconsin show that wind shear is a moderate 10 - 20 knots over 94L, and this shear is keeping any thunderstorms from developing on the system's west side.

The forecast for 94L
The latest of 12Z model runs are more in tune with the idea that 94L will become a tropical storm, with the latest ECMWF run now on board. The storm will be steered west-northwest to northwest over the next three days thanks to the presence to two upper-level lows to the northwest of the storm. Since most of 94L's heavy thunderstorms and high winds are on the east side, the northern Lesser Antilles and Puerto Rico will probably be spared tropical storm force winds from this system. The best guess track for 94L, assuming it does intensify into a tropical storm in the next 24 hours, is on a northwest path between the Bahamas and Bermuda. If 94L stays weak, a more southerly path, along the northern edge of the Bahama Islands, is more likely.

Figure 2. Infrared satellite image taken at 12pm EDT, Tuesday Sep 1, 2009. Five major African tropical waves are apparent. Image credit: Navy Research Lab, Monterey.

Elsewhere in the tropics
It's September, the most active month for hurricane activity in the Northern Hemisphere. There's every indication that the 2009 Atlantic hurricane season will have an active first half of September, since SSTs are 0.5 - 1.0°C above average, wind shear is near average, and the African monsoon is sending a long parade of African waves spinning off the coast of Africa. An IR satellite image from noon today shows this activity well (Figure 2). We can see a line-up of five African waves stretching from the Lesser Antilles to eastern Africa. The GFS model develops the waves numbered "2" and "3" into tropical depressions next week, and the waves labeled "1" and "4" also have a chance to develop into tropical depressions, as well. The wave labeled "1" is mentioned on NHC's Tropical Weather Outlook as having a low (less than 30%) chance of developing into a tropical depression by Thursday. This wave is under a moderate 10 - 15 knots of wind shear, and is over sufficiently warm waters (27 - 28°C) that some development may occur this week. The wave is far enough north that it will be hampered by dry air from the Sahara Desert.

California fire webcams
As I discussed in this morning's post, you can use our wundermap for Los Angeles with the fire layer turned on to see where the fire and smoke are located, and track the temperatures and winds during today's air pollution event. We also have two webcams with views of the fire: Altadena and Tujunga.

Jeff Masters

Backing Down (Fotoguy77)

Part of the massive Station Fire backs down toward Sunland, Ca in this shot taken around 1am. The fire has burned through over 122,000 acres and killed two.

getting out (Fotoguy77)

This fire Chief from El Dorado County in Northern California is chased out of Aliso Canyon by a wall of flames. This was in the Acton area just off the 14 Freeway.

Categories: Hurricane

Permalink | A A A

Top of Page

Reader Comments

Display: 0, 50, 100, 200

Sort: Newest First - Order Posted

Viewing: 3651 - 3701

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 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 | 73 | 74 | 75 | 76 | 77 — Blog Index

3651. PortABeachBum 01:46 PM GMT del 02 Settembre 2009
Quoting superweatherman: history show this may be a GOM storm It also shows it may NOT be a GOM storm! Member Since: Ottobre 4, 2007 Posts: 0 Comments: 198

3652. Thunderground 01:47 PM GMT del 02 Settembre 2009
3618. Mik. Thanks for this info. This is why I love this blog. One can learn so much. I'm forwarding your comment to my hubby so he can look into getting that main electrical panel lightning protection installed both at home at at his office. Member Since: Agosto 31, 2007 Posts: 0 Comments: 89

3653. stormwatcherCI 01:47 PM GMT del 02 Settembre 2009
Quoting StormW: No. Good morning sir. If Erika is really moving wsw now as I see some on here saying what would that mean for intensification and track in the Caribbean ? Member Since: Ottobre 9, 2008 Posts: 0 Comments: 8040

3654. katzanddogz 01:47 PM GMT del 02 Settembre 2009
Quoting StormW: No. LOL Member Since: Febbraio 10, 2009 Posts: 0 Comments: 44

3655. DellOperator 01:49 PM GMT del 02 Settembre 2009
Quoting homegirl: Here's a good question for those who really know their stuff. On the radar, and visual images, you can see a low level circulation, and it's moving WSW. If this is Erika's LLC (I think it is) then Erika is definately moving WSW for the moment. However, what if that is no longer the LLC and a new one has formed under the convection, which the low level swirl seen on visual is now rotating around, giving the appearance of the WSW movement?? Is this at all possible? Absolutely. Currently this storm has multiple vortices (or eddies if you will) that are rotating or flowing about a larger scale low pressure area. And there are multiple vorts not only along the surface, but in the vertical as well which makes the overall direction extremely difficult to determine due to changing flow directions with height. This is a very complex "mixture" of motions which is giving everyone studying this fits. Some of these "swirls" can be absorbed within other swirls or can become ejected. Until this thing begins to consolidate into a single major vortex you are going to see reports of erratic motion as the HH's fly thru this chaotic mess. Anyone else care to comment? DellOP Member Since: Maggio 31, 2007 Posts: 0 Comments: 175

3656. surfmom 01:48 PM GMT del 02 Settembre 2009
3648 - Gotta appreciate your map reading talent. Member Since: Luglio 18, 2007 Posts: 30 Comments: 26538

3657. mikatnight 01:48 PM GMT del 02 Settembre 2009
Quoting justalurker: Erika looks like she is shrinking minute by minute, just like a man whos been in a cold pool for a long time..current trend, DMIN=weak DMAX=strong..i personally see this happening for the next couple of days.. Ya had to use the “man in the pool analogy”, eh? Men are like hurricanes because… Member Since: Ottobre 18, 2005 Posts: 0 Comments: 1971

3658. forestwedder 01:49 PM GMT del 02 Settembre 2009
Just had some clouds move into the area & they are coming in from the WNW here in the cetre of Dominica. They are at about 4500ft as they are touching our highest peaks as they pass through. Member Since: Luglio 18, 2009 Posts: 0 Comments: 25

3660. surfmom 01:50 PM GMT del 02 Settembre 2009
Quoting Thunderground: 3618. Mik. Thanks for this info. This is why I love this blog. One can learn so much. I'm forwarding your comment to my hubby so he can look into getting that main electrical panel lightning protection installed both at home at at his office. Well worth the investment!! All it takes is one hit.. Member Since: Luglio 18, 2007 Posts: 30 Comments: 26538

3661. Booeyb52 01:50 PM GMT del 02 Settembre 2009
Quoting StormW: Here's the deal at the present...looking at the 12Z wind shear from CIMSS, standby for her to possibly regain strength. Looking at RGB satellite loop imagery, Erika IS NOT moving WSW or SW. In fact, looks like we may see a center reformation under the convective flare up. She is moving about 275 right now. The appearance of the SW motion, is the convection being controlled at the 200-700 mb steerng level. That is where the NHC has located the new center per the 8AM advisory. You are on top of it StormW. Ha!

3662. 7544 01:50 PM GMT del 02 Settembre 2009
wow ericka is really loosing the ball of convection to the south at this hour but looks like a new one trying to form right on top of the nhc plot Member Since: Maggio 6, 2007 Posts: 0 Comments: 5925

3663. justalurker 01:50 PM GMT del 02 Settembre 2009
Quoting mikatnight: Ya had to use the “man in the pool analogy”, eh? Men are like hurricanes because… there convection can blow up at any time!! Member Since: Agosto 18, 2009 Posts: 0 Comments: 157

3665. PensacolaDoug 01:50 PM GMT del 02 Settembre 2009
Here's Joe Bastardi's take on it this am. Erika is an island of moist air in the sea of dryness surrounding it. That being said, the areas west of 70 are moist, and this system though spread out has had in increase in overall energy the past 24 hours. I am fairly certain a low-level center will suddenly re-appear under the cloud mass and then we will have a real, live storm. Yesterday's "fake-out" was similar to the Hanna fake-out last year, where sudden deepening of Hanna to 992 north of Hispaniola convinced me I was on the right track with that being a major eastern hurricane. Instead, the stronger system simply pulled in dry air from the island to the south and, once entrained, ruined the core enough so the competing outside bands kept Hanna from firing up. Again, by looking hard at the mistakes one makes, one learns not to get fooled again. Erika's chance for being a big storm is northwest of where it is, in an area in between where other African wave paths have been. Unfortunately, given the pattern, it may be a storm that has a lot of impact on the U.S. East Coast next week Member Since: Luglio 25, 2006 Posts: 0 Comments: 4828

3666. homegirl 01:50 PM GMT del 02 Settembre 2009
Quoting homelesswanderer: AH! So Bob was right! ;) Bob was right, when? Now, or about Rita? If it's the Bob you're talking about, I need to check out his morning analysis. :) Member Since: Agosto 1, 2006 Posts: 45 Comments: 7425

3667. chucky7777 01:51 PM GMT del 02 Settembre 2009
Member Since: Ottobre 19, 2005 Posts: 0 Comments: 174

3670. mikatnight 01:52 PM GMT del 02 Settembre 2009
Quoting hydrus: I thought Australia held that distinction. I'm no expert. I've looked around though and couldn't find one to beat the '35 storm. If you (or someone else) knows different, I'd be interested to know. TIA Member Since: Ottobre 18, 2005 Posts: 0 Comments: 1971

3671. cirrocumulus 01:52 PM GMT del 02 Settembre 2009
Yes, the upper level controls the path. However, there are many factors such as temperature, pressure, land, forests, outflow boundaries that are contributing to the outcome of the upper level changes. For example, the jet stream detected the other night enhanced the reasoning of the "unknown changes" to Erika. Member Since: Settembre 30, 2005 Posts: 0 Comments: 1606

3673. Chucktown 01:53 PM GMT del 02 Settembre 2009
Some of the new runs are trending a little more south. Good news, bad news. Lots of rain for the northern Caribbean islands, but more land interaction means much weaker system if it survives into south Florida. Link Member Since: Agosto 27, 2006 Posts: 0 Comments: 1386

3674. PensacolaDoug 01:53 PM GMT del 02 Settembre 2009
There GOES the neighborhood. Member Since: Luglio 25, 2006 Posts: 0 Comments: 4828

3675. foggymyst 01:54 PM GMT del 02 Settembre 2009
Can anyone provide a layman explanation on Erika and her POSSIBLE track? -TIA (at work blackberry) Member Since: Settembre 23, 2008 Posts: 0 Comments: 383

3676. goavs4 01:54 PM GMT del 02 Settembre 2009
I don't usually worry this early about any systems but with Erika meandering around and this historical track record: http://www.wunderground.com/tropical/tracking/at200906_climo.html#a_topad It makes me a bit nervous since of 12 historical September storms (TS within 200 miles of Erika) 5 were "fish storms", 1 hit the outer banks of NC, and 6 hit the gulf coast somewhere including the 1900 Galveston storm. Thanks for all the folks on here though with level heads and good analysis, it makes sifting through the riffraff worth it! Member Since: Settembre 7, 2007 Posts: 0 Comments: 72

3678. scottsvb 01:55 PM GMT del 02 Settembre 2009
Quoting PensacolaDoug: Here's Joe Basardi's take on it this am. Erika is an island of moist air in the sea of dryness surrounding it. That being said, the areas west of 70 are moist, and this system though spread out has had in increase in overall energy the past 24 hours. I am fairly certain a low-level center will suddenly re-appear under the cloud mass and then we will have a real, live storm. Yesterday's "fake-out" was similar to the Hanna fake-out last year, where sudden deepening of Hanna to 992 north of Hispaniola convinced me I was on the right track with that being a major eastern hurricane. Instead, the stronger system simply pulled in dry air from the island to the south and, once entrained, ruined the core enough so the competing outside bands kept Hanna from firing up. Again, by looking hard at the mistakes one makes, one learns not to get fooled again. Erika's chance for being a big storm is northwest of where it is, in an area in between where other African wave paths have been. Unfortunately, given the pattern, it may be a storm that has a lot of impact on the U.S. East Coast next week Joe B always says the east coast of the U.S. on every system @ first...then says Florida...then says Texas-La... then 24hrs before landfall he give where it will go! I like him for entertainment...but he belongs in Wunderground forums! lol Member Since: Gennaio 22, 2006 Posts: 0 Comments: 1065

3679. hydrus 01:55 PM GMT del 02 Settembre 2009
Quoting StormW: Erika looks like some out of a science fiction book. Does anyone have an idea what is going to happen with this thing? Member Since: Settembre 27, 2007 Posts: 1 Comments: 14297

3680. TheCaneWhisperer 01:56 PM GMT del 02 Settembre 2009
Quoting P451: Spaghetti. Early Cycle. Notice XTRP firing off to the WSW. Not sure if I'd use that as an actual heading as the WSW appearance of Erika is probably more due to center reformation than an actual course change. Yeah, the center reform negates that X-Trap as it will take that into the 6 hour motion which is not accurate.

3681. IKE 01:57 PM GMT del 02 Settembre 2009
Quoting scottsvb: Joe B always says the east coast of the U.S. on every system @ first...then says Florida...then says Texas-La... then 24hrs before landfall he give where it will go! I like him for entertainment...but he belongs in Wunderground forums! lol LOL...amen. Member Since: Giugno 9, 2005 Posts: 23 Comments: 37044

3682. cirrocumulus 01:57 PM GMT del 02 Settembre 2009
Yes StormW. Which is one reason the models have missed the path. They rely on cold hard facts and miss many "butterfly" effects. Member Since: Settembre 30, 2005 Posts: 0 Comments: 1606

3683. mikatnight 01:58 PM GMT del 02 Settembre 2009
Off to work now. Back in the afternoon. Everyone have a good day... Member Since: Ottobre 18, 2005 Posts: 0 Comments: 1971

3685. weathermanwannabe 01:58 PM GMT del 02 Settembre 2009
Erica "barely" made TS status yesterday and is struggling this morning. Any significant interaction with the Greater Antilles would probably doom her unless she ramps up before getting there, or, misses them completely...The next 48 hours will be interesting to watch. Member Since: Agosto 8, 2006 Posts: 0 Comments: 6695

3686. Tropicaddict 01:58 PM GMT del 02 Settembre 2009
can someone tell me if there is anything keeping this storm OUT of the Gulf? Highs, ridges, troughs, etc???? Member Since: Settembre 25, 2007 Posts: 0 Comments: 207

3687. TheCaneWhisperer 01:58 PM GMT del 02 Settembre 2009

3688. Chicklit 01:59 PM GMT del 02 Settembre 2009
Looks like P451 called it right. Member Since: Luglio 11, 2006 Posts: 14 Comments: 10254

3689. sarahjola 01:59 PM GMT del 02 Settembre 2009
Quoting StormW: Here's the deal at the present...looking at the 12Z wind shear from CIMSS, standby for her to possibly regain strength. Looking at RGB satellite loop imagery, Erika IS NOT moving WSW or SW. In fact, looks like we may see a center reformation under the convective flare up. She is moving about 275 right now. The appearance of the SW motion, is the convection being controlled at the 200-700 mb steerng level. again i'm no met, but i just saw on the news that in fact the center is moving wsw and that is coming from the nhc. you are very good at what you do here, but you all are trusting the models too much imo. the nhc has no idea and neither does anyone else about where this storm is going. this storm has proven every professional and model wrong so far. no denying the movement anymore. its now fact! Member Since: Settembre 10, 2008 Posts: 0 Comments: 1291

3690. taco2me61 01:59 PM GMT del 02 Settembre 2009
Quoting hydrus: Erika looks like some out of a science fiction book. Does anyone have an idea what is going to happen with this thing? nope to soon to tell.... really need to wait about 3 more days before we get a good handle on this one.... Member Since: Luglio 7, 2005 Posts: 6 Comments: 2763

3691. PackerFan2 02:00 PM GMT del 02 Settembre 2009
Quoting StormW: Right now, the mid to shallow layer is controlling the path. What's the images I have to use then? Could anyone have predicted that it would stall like this?

3692. CapnK 02:00 PM GMT del 02 Settembre 2009
Quoting hydrus: Erika looks like some out of a science fiction book. Does anyone have an idea what is going to happen with this thing? Nope, not really, not yet. Keep reading here for lots of speculation, though! ;) Member Since: Agosto 21, 2007 Posts: 11 Comments: 109

3693. justalurker 02:00 PM GMT del 02 Settembre 2009
Quoting P451: Looks like convection firing over the "new center" and the other convection is waning. An attempt to tighten up? Or just yet another cycle... is it me or does erika look like she is giving a hand gesture to this blog, saying..try tracking this Member Since: Agosto 18, 2009 Posts: 0 Comments: 157

3694. PackerFan2 02:01 PM GMT del 02 Settembre 2009
Quoting taco2me61: nope to soon to tell.... really need to wait about 3 more days before we get a good handle on this one.... it all depends on where you live, i'm right next to it

3695. lurkn4yrs 02:01 PM GMT del 02 Settembre 2009
Good morning everyone.. This Erika is going to drive us all mad. It looks like she's a party girl ,loves to blow up at night and chill in the morning.. Member Since: Agosto 15, 2009 Posts: 0 Comments: 90

3696. truecajun 02:02 PM GMT del 02 Settembre 2009
good morning everyone. so is she moving south or is it just the convection that makes it look that way? Member Since: Agosto 24, 2006 Posts: 0 Comments: 1848

3697. Chiggy007 02:02 PM GMT del 02 Settembre 2009
Even the most northern models like HWRF and GFDl are now hinting toward FLORIDA! Interesting several days to come...

3699. msphar 02:02 PM GMT del 02 Settembre 2009
Take a break from the Erika dilemma, consider the poor people of Puerto San Carlos (google map it) who took a direct hit from Jimena last night. I would imagine that place is pretty much destroyed. How sad. Member Since: Agosto 20, 2006 Posts: 0 Comments: 258

3700. futurenavymet 02:02 PM GMT del 02 Settembre 2009
ITS GONNA BE A FL STORM BEING SAYING IT FOR FOUR DAYS SO GOM CASTERS CHILL OUT. TX MIGHT GET SOME RAIN FROM A NEW STORM IN THE GOM BUT NOT AIRICKA SOUNDS LIKE PAPRICKA. i like ericka better. sorry had to vent.

3701. hydrus 02:02 PM GMT del 02 Settembre 2009
Quoting mikatnight: I'm no expert. I've looked around though and couldn't find one to beat the '35 storm. If you (or someone else) knows different, I'd be interested to know. TIA I dont know if you have ever read about the labor day storm,but it was a terrible tragedy.I remember talking to the old timers about it and heartbreaking is the only word that comes to mind. I think there were 68 in the Russell family before the storm.There were only 11 or so left after......awful. Member Since: Settembre 27, 2007 Posts: 1 Comments: 14297

Viewing: 3651 - 3701

Top of Page

New Comment

Community Standards Policy 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.

About JeffMasters