98L may develop next week; 97L not a threat to land

By: Dr. Jeff Masters , 1:59 PM GMT on October 09, 2012

Share this Blog
16
+

A tropical wave located about 1000 miles east of the Lesser Antilles Islands (Invest 98L) has a large amount of disorganized heavy thunderstorms, and is headed west-northwest at about 15 mph. Wind shear is a light to moderate 5 - 15 knots over 98L, the atmosphere is moist, and ocean temperatures are a very warm 29°C. With wind shear expected to remain in the moderate range through Wednesday morning, some slow development is likely until 98L encounters much higher wind shear of 20 - 35 knots Wednesday night though Friday. This shear will be due to an upper-level trough of low pressure centered a few hundred miles northeast of the Lesser Antilles Islands. Moisture from 98L could arrive in the Lesser Antilles Islands as early as Thursday night. Wind shear may drop to levels capable of allowing 98L to develop into a tropical depression by Saturday, as predicted by the NOGAPS model. The GFS model predicts shear will remain high until early next week. The GFS develops 98L into a tropical depression on Tuesday, a few hundred miles northeast of the northernmost Lesser Antilles Islands. In their 8 am Tropical Weather Outlook, NHC gave 98L a 20% chance of becoming a tropical cyclone by Thursday morning. The long range fate of 98L is uncertain; the ECMWF model shows 98L coming close to the U.S. East Coast in ten or so days, while the other models keep 98L far out to sea.


Figure 1. Morning satellite image of Invest 98L headed towards the Lesser Antilles Islands.

97L near the Bahamas little threat to develop
A tropical disturbance a few hundred miles northeast of the Bahama Islands (Invest 97L) has a moderate amount of disorganized heavy thunderstorms, and is headed northeast at about 10 mph. Satellite loops show that heavy showers from 97L are affecting portions of the Southeast Bahama Islands, and this activity will continue today. Wind shear is a moderate 15 - 20 knots over 97L, but is expected to rise to the high range, 20 - 30 knots, on Tuesday night. This high shear should prevent 97L from developing as it heads northeastwards out to sea. In their 8 am Tropical Weather Outlook, NHC gave 97L a 10% chance of becoming a tropical cyclone by Thursday morning. Rains from 97L will not affect the U.S.

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: 48 - 1

Page: 1 — Blog Index

48. WunderAlertBot (Admin)
4:25 PM GMT on October 09, 2012
JeffMasters has created a new entry.
47. AussieStorm
4:17 PM GMT on October 09, 2012
At the NWA 37th Annual Meeting. The SPC revealed it has an experimental program and could add a few more categories to it's outlooks, currently it's Slight, Moderate and High. The new scale could be Slight, Marginal, Enhanced, Moderate and High.


Also at the NWA conference it was announced new WX Radios will contain GPS locators so it will know where it will be located in the forecast polygon.

Also announced the new GOES-R.
Member Since: September 30, 2007 Posts: 9 Comments: 15935
46. whitewabit (Mod)
4:08 PM GMT on October 09, 2012
Supersonic dive from edge of space put on hold
Member Since: August 17, 2005 Posts: 362 Comments: 31392
45. VR46L
4:05 PM GMT on October 09, 2012
Quoting TomballTXPride:

Wow. I'm surprised. Utterly shocked. Wow.


I am completely stunned ...LOL
Member Since: March 1, 2012 Posts: 0 Comments: 6898
44. AussieStorm
4:05 PM GMT on October 09, 2012
Quoting VR46L:


That interesting !!! So it is a marketing exercise , never would have thought that.....
Quoting TomballTXPride:

Wow. I'm surprised. Utterly shocked. Wow.


yeah, who would of thunk it. lol
Member Since: September 30, 2007 Posts: 9 Comments: 15935
42. VR46L
4:01 PM GMT on October 09, 2012
Quoting AussieStorm:
TWC naming criteria was revealed on WeatherBrains last night. Bryan Norcross revealed the criteria. He also said it was more of a marketing and a social media than a meteorological/science aim. The criteria is.....

1.Consider naming a storm if a storm will make significant impact,ice an snow.

2. Significant disruption to road and air travel.

3. If it was to cause life threatening conditions due to wind, snow, ice and cold.


That interesting !!! So it is a marketing exercise , never would have thought that.....
Member Since: March 1, 2012 Posts: 0 Comments: 6898
41. NttyGrtty
3:55 PM GMT on October 09, 2012
Thanks Jeff...
Member Since: February 11, 2010 Posts: 0 Comments: 834
40. AussieStorm
3:53 PM GMT on October 09, 2012
TWC naming criteria was revealed on WeatherBrains last night. Bryan Norcross revealed the criteria. He also said it was more of a marketing and a social media than a meteorological/science aim. The criteria is.....

1.Consider naming a storm if a storm will make significant impact,ice an snow.

2. Significant disruption to road and air travel.

3. If it was to cause life threatening conditions due to wind, snow, ice and cold.

This will be officially be revealed next week on TWC. There will also be another part to be released in about 2 weeks as it yet to be finalised.
Member Since: September 30, 2007 Posts: 9 Comments: 15935
39. islander101010
3:44 PM GMT on October 09, 2012
remember 95? http://en.wikipedia.org/wiki/Hurricane_Marilyn
Member Since: September 11, 2010 Posts: 1 Comments: 4589
38. VR46L
3:43 PM GMT on October 09, 2012
Caribbean water vapor Image

Member Since: March 1, 2012 Posts: 0 Comments: 6898
36. CaribBoy
3:20 PM GMT on October 09, 2012
Interestingly, Hurricane OMAR in 2008 began as INVEST 98L lol. It crossed the NE Carib on october 15th - 16th
Member Since: October 6, 2007 Posts: 0 Comments: 6168
35. CaribBoy
3:18 PM GMT on October 09, 2012
12Z NAM

Member Since: October 6, 2007 Posts: 0 Comments: 6168
34. goalexgo
3:15 PM GMT on October 09, 2012
Here in NJ, we are already pretty worried about 98L.
Member Since: June 28, 2010 Posts: 0 Comments: 127
33. Patrap
3:15 PM GMT on October 09, 2012
Looking downstream,,the thingee in the Caribbean has about a 0% chance of developing as the CONUS fronts are in Shields up Mode Cpt'n.


Member Since: July 3, 2005 Posts: 424 Comments: 128279
32. AussieStorm
3:14 PM GMT on October 09, 2012
Pacific eases further away from El Niņo thresholds

The chance of El Niņo developing in 2012 has reduced over the past fortnight. The tropical Pacific continued its retreat from El Niņo thresholds for the second consecutive fortnight (i.e., ocean temperatures cooled), remaining within the neutral range (neither El Niņo nor La Niņa). Other ENSO indicators such as the Southern Oscillation Index (SOI) and tropical cloud patterns have persisted at neutral levels since late July.

Given the rate of ocean cooling, and the continued neutral conditions in the atmosphere, the chance of an El Niņo developing in 2012 has reduced further over the past fortnight. However, some risk still remains while the trade winds in the western Pacific continue to be weaker than normal. Climate models surveyed by the Bureau of Meteorology have increased their chances of sea surface temperatures in the tropical Pacific Ocean remaining at neutral levels, though still warmer than average, for the remainder of 2012.

The Indian Ocean Dipole (IOD) is likely to return to neutral values during the latter half of the southern spring, according to outlooks from the Bureau%u2019s climate model. The IOD index has been consistently above 0.4 °C since mid-July, indicative of a positive IOD event. A positive IOD is typically associated with decreased winter and spring rainfall over parts of southern, central and northern Australia.











Member Since: September 30, 2007 Posts: 9 Comments: 15935
31. FtMyersgal
3:13 PM GMT on October 09, 2012
Quoting Grothar:


Well I'm disturbed about it.


Me too Grothar. Me too.
Member Since: September 16, 2010 Posts: 0 Comments: 1216
30. Grothar
3:12 PM GMT on October 09, 2012
Quoting bappit:

Apparently it doesn't qualify as being a disturbance.



Well I'm disturbed about it.
Member Since: July 17, 2009 Posts: 71 Comments: 26131
29. FtMyersgal
3:10 PM GMT on October 09, 2012
Thanks for the update Dr. Masters. Any thoughts on the blob south of Jamacia?
Member Since: September 16, 2010 Posts: 0 Comments: 1216
28. SSideBrac
3:09 PM GMT on October 09, 2012
I suspect that an outbreak of Blob Fever is about to happen
Member Since: September 21, 2008 Posts: 0 Comments: 266
27. AussieStorm
3:06 PM GMT on October 09, 2012
26. bappit
3:00 PM GMT on October 09, 2012
Quoting Grothar:
Thanks, Doc. Anything about the disturbance in the Caribbean.

Apparently it doesn't qualify as being a disturbance.

Member Since: May 18, 2006 Posts: 10 Comments: 6025
25. unknowncomic
2:38 PM GMT on October 09, 2012
Member Since: August 2, 2011 Posts: 0 Comments: 1929
24. GTcooliebai
2:35 PM GMT on October 09, 2012
Quoting SFLWeatherman:
WPB!:)
This morning was cool along the West Coast of FL. Expected to get morning lows in the Upper 60s on Wed. and Thurs.

And upper 50s north and in our normally cooler spots away from the water.

Member Since: August 31, 2009 Posts: 0 Comments: 5628
23. SFLWeatherman
2:34 PM GMT on October 09, 2012
Friday!!!:) Mostly sunny, with a high near 85. Breezy, with a northeast wind 9 to 16 mph, with gusts as high as 21 mph.
Member Since: May 23, 2012 Posts: 0 Comments: 4521
22. Slamguitar
2:34 PM GMT on October 09, 2012
Thanks Doc! And they say the tropics are boring and are going to shut down soon...
Member Since: July 2, 2011 Posts: 0 Comments: 1183
21. SFLWeatherman
2:31 PM GMT on October 09, 2012
WPB!:)
Member Since: May 23, 2012 Posts: 0 Comments: 4521
20. SFLWeatherman
2:31 PM GMT on October 09, 2012
Member Since: May 23, 2012 Posts: 0 Comments: 4521
19. AussieStorm
2:31 PM GMT on October 09, 2012
Quoting Patrap:
.."Upon us all, all, a lil rain must fall"...

and looking at the next 5 days, only the SE US will miss out, except for souther Florida still.
Member Since: September 30, 2007 Posts: 9 Comments: 15935
18. Patrap
2:28 PM GMT on October 09, 2012
.."Upon us all, all, a lil rain must fall"...
Member Since: July 3, 2005 Posts: 424 Comments: 128279
17. AussieStorm
2:26 PM GMT on October 09, 2012
Quoting TomballTXPride:
Other than the Upper Great Lakes and Cape Cod Regions where the 12Z NAM is depicting some decent rainfall totals, the rest of the conterminous U.S. looks fairly dry for the next 24 hours.



Slightly different.



next 5 days...


Nice rain coverage.
Member Since: September 30, 2007 Posts: 9 Comments: 15935
16. VR46L
2:25 PM GMT on October 09, 2012
Thanks Doc !!!

Lots and lots of blobs ... ok 2 are invests but the blob in the west Caribbean might be needed to be watched

Flash embedded

Link
Member Since: March 1, 2012 Posts: 0 Comments: 6898
15. GTcooliebai
2:25 PM GMT on October 09, 2012
Quoting CybrTeddy:
98L is at 9N trucking at 24mph straight west. It will be difficult to go north of the islands if this maintains.
If it stays weak and disorganized then it will probably take the southern route or the east to west zonal flow, but if it gains strength it may be able to feel the weakness in the ridge which is displaced to the north.

Member Since: August 31, 2009 Posts: 0 Comments: 5628
13. hurricaneivan
2:20 PM GMT on October 09, 2012
Quoting CybrTeddy:
98L is at 9N trucking at 24mph straight west. It will be difficult to go north of the islands if this maintains.
agreed
Member Since: October 6, 2012 Posts: 0 Comments: 7
12. Patrap
2:18 PM GMT on October 09, 2012
All Tropical Cyclone Imagery - Storm Floaters
Member Since: July 3, 2005 Posts: 424 Comments: 128279
11. CybrTeddy
2:18 PM GMT on October 09, 2012
98L is at 9N trucking at 24mph straight west. It will be difficult to go north of the islands if this maintains.
Member Since: July 8, 2005 Posts: 259 Comments: 24021
9. PalmBeachWeather
2:14 PM GMT on October 09, 2012
Thank you Dr. Masters
Member Since: October 3, 2008 Posts: 0 Comments: 5864
7. Grothar
2:08 PM GMT on October 09, 2012
Member Since: July 17, 2009 Posts: 71 Comments: 26131
6. islander101010
2:06 PM GMT on October 09, 2012
sw carib. is like a new girl at the bar take some time to scope out. red bull is covering felix:s jump from space.
Member Since: September 11, 2010 Posts: 1 Comments: 4589
5. Patrap
2:06 PM GMT on October 09, 2012
98L

Night IR to Vis Loop



Member Since: July 3, 2005 Posts: 424 Comments: 128279
4. AussieStorm
2:05 PM GMT on October 09, 2012
Dr Masters, I noticed you've brought the shear for 98L down from 20-40kts(from last blog) to 20-30kts. Any reason? Is this shear drop going to continue?

Thanks for the updates on 97L and 98L.
Member Since: September 30, 2007 Posts: 9 Comments: 15935
3. islander101010
2:05 PM GMT on October 09, 2012
98 still alot of unknowns thanks
Member Since: September 11, 2010 Posts: 1 Comments: 4589
2. mks
2:03 PM GMT on October 09, 2012
Thanks Doc!
Member Since: August 10, 2008 Posts: 0 Comments: 2
1. Grothar
2:03 PM GMT on October 09, 2012
Thanks, Doc. Anything about the disturbance in the Caribbean.
Member Since: July 17, 2009 Posts: 71 Comments: 26131

Viewing: 48 - 1

Page: 1 — Blog 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

Partly Cloudy
83 °F
Partly Cloudy