Felicia not weakening; new African wave may develop
Hurricane Felicia has not weakened today, and continues to hold its own in spite of cool sea surface temperatures beneath it. Recent satellite imagery shows that the tops of thunderstorms surrounding the eye have cooled slightly, indicating that the updrafts sustaining the eyewall are maintaining their strength. The appearance of the hurricane has improved some today, with the storm assuming a more symmetric appearance.
Figure 1. Current satellite image of Hurricane Felicia.
Sea surface temperatures (SSTs) under Felicia have now fallen to 24.7ยฐC, well below the 26ยฐC threshold typically needed to sustain a hurricane. SSTs will slowly increase to 26ยฐC by the time the storm reaches Hawaii, though. Wind shear is expected to remain low to moderate, 5 - 15 knots, through Monday morning. By Monday night, shear will rise to 20 knots, and remain above 20 knots thereafter. The higher shear combined with the relatively cool SSTs should mean that Felicia will be rapidly weakening in its final 24 hours before reaching Hawaii. Several of the computer models continue to show that this shear will be high enough to tear Felicia apart before it reaches Hawaii, though it appears to me that Felicia's current strength and annular structure will help it resist the shear enough to allow the storm to hit Hawaii as a tropical depression with 35 mph winds. Regardless, Felicia will bring heavy rain Hawaii beginning on Monday morning, and these rains will have the capability of causing flash floods and mudslides. The Hurricane Hunters are scheduled to make their first low-level investigation of Felicia this afternoon (around 10 am Hawaiian time). The NOAA jet also flies into Felicia today, and will drop a series of dropsondes that will be used to gather data that will be fed into today's 12Z and 00Z computer model runs.
Typhoon Morakot hits Taiwan
Typhoon Morakot hit Taiwan yesterday, battering the island with Category 1 winds and heavy rain. The Taipei airport recorded sustained winds of 56 mph, gusting to 76 mph, at the peak of the storm. Morakot killed 6 on Taiwan and 10 in the Philippines, and is headed towards a final landfall on mainland China as a tropical storm later today. Storm chaser James Reynolds intercepted the storm and posted videos on typhoonfury.com and Youtube. Morakot is still visible today on Taiwan radar.
Figure 2. Visible satellite image of a spinning tropical wave leaving the coast of Africa. The image was taken at 8am EDT 8/8/09.
African tropical wave may develop
A strong tropical wave with a moderate amount of spin is moving off the coast of Africa this morning. The wave is under about 10 - 20 knots of wind shear and has sea surface temperatures beneath it of 27ยฐC. These conditions are probably too marginal to allow development over the next two days. As the wave moves westward away from Africa over the next few days, wind shear should slowly decrease and the SSTs will warm, potentially allowing for some slow development. The UKMET, GFS, and NOGAPS models all indicate the possibility that this will become a tropical depression 3 - 5 days from now. The ECMWF model forecasts that strong easterly winds over the wave will create too much shear to allow development. The wave is well south of the Saharan Air Layer, so dry air and African dust should not interfere over the next 3 - 5 days. I give the wave a medium (30 - 50% chance) of developing into a tropical depression in the next seven days.
I'll have an update on Sunday.
Jeff Masters
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Reflector site for those at work, which includes Weather456, daily update.
AOI
AOI
Shows you that they truly lack any sort of weather knowledge or common sense.
Have been at a yard sale all day. What's new in the tropics? I see the TW that's just now coming off the coast of Africa. Dr. Masters is looking at it pretty closly. May become Ana pretty soon. Any thoughts?
CK
After looking at several diffrent images of the african wave...
I don't think the COC has even left the coast yet..
but the convection fireing on the N side is a good sign that there is uplift in the region.
You Rang?
You are crazy lol, please tell me your lurk more than you post
Wassup with you?
Tropical Cyclone Advisory #21
SEVERE TROPICAL CYCLONE FELICIA (EP082009)
21:00 PM UTC August 8 2009
====================================
Interests In Hawaii Should Monitor The Progression Of This Cyclone.. A Tropical Storm Watch May Be Issued Later Today or Tonight For Portions Of Hawaii
At 18:00 PM UTC, Hurricane Felicia (981 hPa) located at 19.8N 142.1W or 735 NM east of of Hilo, Hawaii has sustained winds of 75 knots with gusts of 90 knots. The cyclone is reported as moving west at 13 knots.
Hurricane-force Winds
====================
30 NM from the center
Gale/Storm-force Winds
===============
100 NM from the center
Forecast and Intensity
======================
12 HRS: 20.1N 144.1W - 65 knots (SSHS-1 Cyclone)
24 HRS: 20.1N 146.8W - 60 knots (Tropical Storm)
48 HRS: 20.0N 152.4W - 40 knots (Tropical Storm)
72 HRS: 20.0N 158.0W - 30 knots (Tropical Depression)
90L in the East Pacific has a good spin but is lacking convection. I give it a 25% of becoming a TD before dissipating.
Wave off of Africa looking good as night approaches over there. I give it a 50-70% of being a TD over the next five days.
the models don't do anything much with it. its just another one of those that come off looking robust and then crumble.....
you labled it right a BLOB and i guess thats why no one has mentioned it
lol ok you go on thinking that, its your opinion
If your referring to the African wave you'd be wrong there. Shear's lessening, SST's are plenty warm enough too.
Just because he disagrees and is in the minority does not make him a troll haha.
a 5 mile wide swath of 30 knots isnt close to where the MLC is, the 20 knots wont affect it too much, just maybe curtail it in the short term
If you look at the map, 5-10 knots is located around where the MLC is
I do believe it is currently under about 20kts but you are right, about to hit more favorable shear levels and warmer water. It will not blow up in the next 24-48 hours but an invest in about 48-72 hours is not out of the question. Doing my long range forcasting, south FL needs to watch this wave and if the ridge builds in farther it could sneak into the Gulf which I hope it doesnt.
When they don't place forward a valid reason like 'I don't think this will develop: Reasons, I think the wind shear will be too high to prevent development in the long term, and the SAL might be to strong and will induce into the system' THAT is a valid forecast, but just placing out there 'omg convection dissipaiting (even though its DMIN) RIP' or something along the lines of that, it causes arguments in the blogs and insults and the blog errupts into chaos. Most of the time, I just ignore the people who place that out. Including wishcasters who come out and say 'OMG! TD by afternoon' (which usually when the convection dissipates they always turn around and say 'RIP')
thankyou... finaly you have some respect
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