Hawaii braces for Felicia; 99L near the Cape Verdes Islands may develop
A strong tropical wave (99L) is just south of the Cape Verdes Islands, 800 miles off the coast of Africa. This morning's QuikSCAT pass showed a nearly closed surface circulation, stretched out along one axis. The satellite saw winds of up to 45 mph in a band of heavy thunderstorms well south of the Cape Verdes Islands. The islands have seen winds of only 10 - 15 mph and some occasional rain showers thus far from the disturbance. Heavy thunderstorm activity associated with 99L died down this morning, but appears to be making a comeback late this morning. Wind shear is moderate, about 10 knots, and sea surface temperatures are moderately warm, about 27 - 28°C. There is a large area of dry air to 99L's north that is interfering with the storm's organization, though.
Figure 1. Current satellite image of disturbance 99L.
Wind shear is expected to be moderate, 5 - 15 knots, through Wednesday. SSTs will remain relatively constant at 27°C, but the dry, stable air of the Saharan AIr Layer (SAL) to 99L's north will be problem for it. NHC has given 99L a moderate (30 - 50% chance) of developing into a tropical depression by Wednesday morning, which is a reasonable forecast. Most of the models show some weak development, but none of them predict 99L will become a hurricane. It is too early to say if 99L will recurve north of the Lesser Antilles Islands or not, since it will be at least 5 days before the storm makes it that far. It is unusual, though, for storms forming this far north to make it all the way across the Atlantic to hit the Lesser Antilles Islands.
The GFS and ECMWF models are predicting the possible development of a new tropical wave coming off the coast of Africa late this week.
Felicia continues to weaken, but is a flash flooding threat to Hawaii
Tropical Storm Felicia has weakened steadily over the past 24 hours, thanks to cool sea surface temperatures and increasing shear. Recent satellite loops show that strong upper-level winds from the west have pushed the storm's heavy thunderstorm activity to the northeast side of the center, exposing the surface center as a swirl of low clouds. Felicia's relatively meager heavy thunderstorm activity is steadily moving away from the center of the storm.
Figure 2. History of hurricane activity over Hawaii since 1950. Hawaii islands have been hit by only 9 tropical cyclones of tropical depression or greater strength, with 4 others passing withing 75 miles of an island. Image credit: NOAA Coastal Services Center.
Sea surface temperatures (SSTs) under Felicia are 25°C, well below the 26°C threshold typically needed to sustain a hurricane. SSTs will slowly increase to 26°C by Tuesday. Wind shear has increased to a high 30 knots, and is expected to increase further to 40 knots by Tuesday. The high shear combined with the cool SSTs should continue to weaken Felicia today. I give a 30% chance that the shear will completely rip away Felicia's heavy thunderstorm activity by the time the storm reaches Hawaii, leaving only a swirl of low-level clouds that will not cause significant flooding problems. The wind speed probabilities forecast shows about a 25% chance Felicia will still be a weak tropical storm at 3 am Hawaiian time Tuesday morning, and a 15% chance the storm will have dissipated. If Felicia does hold together that long, it would be only the tenth tropical cyclone of tropical depression or higher strength to affect the islands since 1950 (Figure 2). Large swells from Felicia are already affecting the Big Island, and a high surf warning has been posted for east-facing shores of the Big Island and other Hawaiian islands. Felicia or its remnants may bring heavy rain, flash flooding, and mud slides to the islands beginning this afternoon, and a Flash Flood Watch has been posted for most of the islands.
Links to follow:
Long range radar from the Big Island
Wundermap for Hawaii
I'll have an update Tuesday morning.
Reader Comments
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 — Blog Index
I'd focus more on 99L and the wave near 45W
Hardly any. LOL! The NHC says conditions are favorable.
Yes, it is he...he is the chosen one!
This is the wave that has a greater chance and 99L
Indeed...
Gosh I resemble that remark - was 14 and had just moved from Bay St Louis to P'cola
That wave is just another 97L; I hate waves like that.
Did make for some nice Redfish holes in the "new" Ship Island(s) pass. :)
...just curious...from what language does this word come?
you mean diurnal minimum?
Yes lol
I think you mean vulnerable to diurnal MINimum. Diurnal max will only assist this feature. Just because a system fluctuates in terms of heavy convection doesn't mean it';s over. People are always so quick to write a system off because or warming cloud tops (an almost guaranteed process in developing systems)
Good to be seen...as a good friend used to say, any day you wake up on the right side of the grass is a good one...LOL
So we have some features to discuss it seems...the bit in the Antilles looks interesting in a Chinese sort of way, huh?
On the contrary, I am appalled to see people paying less attention to the other waves east of the Antilles wave, which have a greater chance. 99L still has a far greater chance.
it needs more Upper Level Divergence or in other words an Anticyclone to help it breathe and create outflow
The weather channel is the suck. A cat 5 could be bearing down on South Florida and they would be reporting from Gerogia saying that the storm isnt too bad...
AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS
ORIGIN TIME - 1956Z 10 AUG 2009
COORDINATES - 14.1 NORTH 93.0 EAST
LOCATION - ANDAMAN ISLANDS INDIA REGION
MAGNITUDE - 7.7
EVALUATION
EARTHQUAKES OF THIS SIZE HAVE THE POTENTIAL TO GENERATE A
DESTRUCTIVE LOCAL TSUNAMI AND SOMETIMES A DESTRUCTIVE REGIONAL
TSUNAMI ALONG COASTS LOCATED USUALLY NO MORE THAN A THOUSAND
KILOMETERS FROM THE EARTHQUAKE EPICENTER. AREAS FURTHER FROM THE
EPICENTER COULD EXPERIENCE SMALL SEA LEVEL CHANGES AND STRONG OR
UNUSUAL COASTAL CURRENTS.
HOWEVER - IT IS NOT KNOWN THAT A TSUNAMI WAS GENERATED. THIS
WATCH IS BASED ONLY ON THE EARTHQUAKE EVALUATION. AUTHORITIES IN
THE REGION SHOULD TAKE APPROPRIATE ACTION IN RESPONSE TO THIS
POSSIBILITY. THE WATCH WILL NOT EXPAND TO OTHER AREAS OF THE
INDIAN OCEAN UNLESS ADDITIONAL DATA ARE RECEIVED TO WARRANT SUCH
AN EXPANSION.
Outflow is the major inhibiting factor with the wave near Barbados.
INV/99L/XX
Good question...since tsunamis (whatever the plural of that is) tend to extend from the surface down through the deepest levels of the ocean, it might cause cooler water from the depths to surge up to the surface. Just an educated guess, though...
Apparently it's a new word, having something to do with the spin axis of Rick Moranis...maybe Canadian, huh?
There was a TCFA issued but I doubt it gets renewed tonight.
Yes Voricity levels are there in the 850 mb level but it is imbalanced...The convergence and divergence are the same if it can gain some divergence aloft which could happen with sustainable convection or an anticyclone then the low will be able to deepen and pressure could start falling....Looking at the maps it looks to be a mid level low it will have to deepen to make its way down to the surface
...ah....that explains it...thanks ; )
AOI/XX/XXL
MARK
13.3N/59.4W
Doubtful, I dont think a moving tsunami wave would cause much upwelling since it is a different type of wave than surface waves cause by wind.
Tsunami's generally only move one direction away from the main energy source leaving waters relatively undisturbed till they get to shore. It would basically move under all the other waves and leave the surface undisturbed.
Of course I could be totally wrong, but that's the best description based on my understanding of tsunami's...which isnt much. haha
yeah thats what i was thinking also i knew it would inhibit developement if anything
...you are correct, sir...,
Yeah my browser says this page has "security certificate errors". Somebody must have posted something from a restricted access site.
Viewing: 1051 - 1101
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 — Blog Index