Tropical Wave with low near African Coast

[frederic79]

I noticed that, too. I'll be curious to see if it persists with time. It's a fairly low latitude and has some SAL to deal with but who knows?

[cheezyWXguy]

2 PM Discussion from TPC:

A TROPICAL WAVE IS MOVING OFF THE COAST OF AFRICA ALONG 16W/17W
SOUTH OF 18N. A 1009 MB LOW PRESSURE CENTER IS ALONG THE WAVE
AXIS NEAR 11N17W. THIS WAVE SHOWS SOME SIGNS OF ORGANIZATION.
SOME SLOW DEVELOPMENT OF THIS SYSTEM IS POSSIBLE DURING THE NEXT
COUPLE OF DAYS AS IT MOVES TO THE WEST-NORTHWEST ABOUT 15 MPH.
SCATTERED MODERATE CONVECTION IS FROM 9N-14N BETWEEN 15W-20W.

http://www.storm2k.org/weather/hw3.php? ... hwvmetric=

sounds like the TWO and TWD are written by 2 different people...

[RL3AO]

sounds like the TWO and TWD are written by 2 different people...

They are. Usually the TWO is written by one of the hurricane specialists and the TWD is written by one of the TAFB mets.

[tolakram]

TWO ... FORECASTER BLAKE

TWD ... FORMOSA

Yes.

[cycloneye]

The latest pic at 5 PM EDT:

[BigA]

Impressive blowup of convection on northern side...but it's moving at a snail's pace.

[OURAGAN]

Look really good!

http://www.nrlmry.navy.mil/sat-bin/disp ... C_SCALE=15

[SouthFloridawx]

Yes it is looking good.

EUMETSAT DUST. Cool thing about this is that you can see where the dry are and dust is in the picture.

http://oiswww.eumetsat.org/IPPS/html/DerivedProducts/MSG2/DUST/WESTERNAFRICA/index.htm

[RL3AO]

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT TUE JUL 29 2008

<snip>
...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 16W/17W S OF 18N MOVING W AT 15 KT WITH A
1008 MB LOW ALONG THE WAVE NEAR 12N. WAVE IS EMBEDDED WITHIN A
DEEP LAYER OF MOISTURE BASED ON THE MIMIC-TPW. A MID LEVEL
ROTATION IS JUST TO THE NE OF THE SURFACE LOW. ALTHOUGH THIS
WAVE SHOWS SOME SIGNS OF ORGANIZATION...DEVELOPMENT...IF
ANY...IS EXPECTED TO BE SLOW TO OCCUR. SCATTERED/NUMEROUS STRONG
CONVECTION IS N OF THE SURFACE LOW FROM 12N-16N BETWEEN 17W-19W.
</snip>

$$
WALLACE

http://www.nhc.noaa.gov/text/refresh/MIATWDAT+shtml/292336.shtml?

[cycloneye]

ABNT20 KNHC 292351
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT TUE JUL 29 2008

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

A TROPICAL WAVE JUST OFFSHORE OF THE WEST COAST OF AFRICA...NEAR
DAKAR SENEGAL...IS MOVING SLOWLY WEST-NORTHWESTWARD.
DEVELOPMENT...IF ANY...OF THIS SYSTEM IS EXPECTED TO BE SLOW TO
OCCUR.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER PASCH

http://asp1.sbs.ohio-state.edu/tropical ... c/outlook/

[RL3AO]

New quikscat.



Low at 13N 18W.

[cycloneye]

Here are observations from Dakar,Senegal from early this morning until 8 PM,where low pressure readings and change in the wind direction tells us that a low pressure is close to that location.

Code: Select all

 Time
EDT (UTC)  Temperature
F (C)  Dew Point
F (C)  Pressure
Inches (hPa)  Wind
MPH  Weather
Latest 8 PM (0) Jul 29 77 (25) 75 (24) 29.80 (1009) ENE 9 light rain with thunder
 7 PM (23) Jul 29 77 (25) 75 (24) 29.83 (1010) ENE 10 light rain with thunder
 6 PM (22) Jul 29 77 (25) 73 (23) 29.80 (1009) ENE 13 light rain with thunder
 5 PM (21) Jul 29 77 (25) 75 (24) 29.80 (1009) ENE 12 light rain with thunder
 4 PM (20) Jul 29 78 (26) 73 (23) 29.77 (1008) ENE 15 rain with thunder
 3 PM (19) Jul 29 84 (29) 75 (24) 29.77 (1008) NNW 8 
 2 PM (18) Jul 29 84 (29) 73 (23) 29.74 (1007) N 8 
 1 PM (17) Jul 29 87 (31) 69 (21) 29.74 (1007) N 6 
 Noon (16) Jul 29 87 (31) 71 (22) 29.74 (1007) N 6 
 11 AM (15) Jul 29 89 (32) 69 (21) 29.77 (1008) E 7 
 10 AM (14) Jul 29 86 (30) 75 (24) 29.80 (1009) NNW 7 
 9 AM (13) Jul 29 84 (29) 73 (23) 29.83 (1010) N 10 
 8 AM (12) Jul 29 84 (29) 73 (23) 29.85 (1011) N 10 
 7 AM (11) Jul 29 84 (29) 73 (23) 29.85 (1011) N 12 
 6 AM (10) Jul 29 84 (29) 71 (22) 29.85 (1011) NNE 9 
 5 AM (9) Jul 29 82 (28) 71 (22) 29.85 (1011) N 7


http://weather.noaa.gov/weather/current/GOOY.html

[MiamiensisWx]

The following post is NOT an official prognosis.

Personally, I've been very skeptical in regards to the vitality of this system's future and even its development over the past few days. The main issue is the thermal ridge at 700 mb and very stable SAL to the north and west of the surface low, which is exiting the coast at a high latitude like Bertha, reflecting the persistent northward bias of several African lows this year. The capping from the SAL is denoted on satellite imagery by the stratocumulus across the eastern and central subtropical Atlantic. When combined with the fact that the low level (850 mb) vorticity associated with this wave was not as great as pre-Bertha, I have strongly doubted this system's long term prospects. However, if it can maintain strong convection with greater low level inflow in the vicinity of the surface low, it may maintain itself or even intensify over the next several days. It will encounter low shear within the short term, though the SAL and cooler SSTs/OHC north and west of the Cape Verde islands will be a limiting factor. Regardless, it is noted that Bertha also faced similar ills with the SAL and SSTs/OHC, and it still intensified and eventually became a hurricane because of the very conducive upper air synoptic regime. Overall, if convection can continually develop over the surface low, this one may receive an INVEST classification and slowly intensify to a tropical storm over the next several days. The system will likely encounter upper level shear in the medium to long term, as an upper low moves southward, which is supported by WV data and the operational GFS. Since the synoptic environment will not be as favorable as Bertha, I definitely do not anticipate a stronger system than TS status (at most). It's a definite fish (i.e. not a threat to any land mass, including Bermuda/Lesser Antilles/Caribbean) as well.

...and I apologize for my preceding MJO comment's superficial "harshness" to Luis in another thread. It was not intentional.

[cycloneye]

Ok peeps,its now invest 98L,Thread locked.Go to active storms forum for all the details and you can make comments about the system there.