ATL: INVEST 90L - Discussion

[SeGaBob]

I'm going to go out on a limb and say that this one will develop the furthest east compared to previous systems this year. (No reasoning really just that feeling.)

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[YoshiMike]

LOL just wingin it? Got that feelin in your gut buddy?

[Gustywind]

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI SEP 05 2014

A TROPICAL WAVE ASSOCIATED WITH A 1009 MB LOW PRESSURE CENTER IS
OVER THE CAPE VERDE ISLANDS. ITS AXIS EXTENDS FROM 18N22W TO THE
LOW NEAR 14N23W TO 07N23W...MOVING WEST AT 10-15 KT. SSMI TOTAL
PRECIPITABLE WATER VAPOR IMAGERY SHOWS A MOIST ENVIRONMENT
MAINLY N OF THE LOW FROM 12N-18N BETWEEN 18W-26W. ISOLATED
MODERATE CONVECTION IS FROM 11N-16N BETWEEN 23W-27W...COINCIDING
WITH A REGION OF DEEP LAYER HIGH MOISTURE.

[Nimbus]

The surface pressure of 95L rose to 1012 a "shallow" system at 20 degrees latitude on August 16.

Three weeks later the conditions are a little more conducive for development.
It will be interesting to see how far west 90L can get before dry air and shear induce the 3 mb poof.

[Chris_in_Tampa]

Global Hawk UAV is on the way to 90L:
http://airbornescience.nasa.gov/tracker/

It left Virginia at around 7am EDT for a 25 hour flight.

From yesterday's mission schedule:
"AV-6 to fly Science Flight #4 tomorrow (target I90L/P27L off African coast; 60 sondes loaded)."
https://espo.nasa.gov/missions/hs3/daily-schedule

From NHC's Plan of the Day:

Code: Select all

    3. REMARKS: GLOBAL HAWK NASA872 WILL DO A TROPICAL
       WAVE/ SAHARA DUST INTERACTION RESEARCH FLIGHT DEPARTING
       KWAL AT 05/1100Z. FLIGHT LEVEL 55,000 TO 62,000 FT.
       DURATION: 05/1100Z TO 06/1200Z. 60 SONDES TOTAL-           
       RACE TRACK PATTERN WITHIN BOX ORIENTED N TO S WILL           
       BE FLOWN FROM W TO E IN REGION BOUNDED BY:
        A. 17.48N 30.17W
        B. 9.50N 30.16W
        C. 9.50N 23.91W
        D. 17.48N 23.91W

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT FRI SEP 5 2014

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

An area of low pressure, associated with a tropical wave, is
producing disorganized cloudiness and thunderstorms near and south
of the Cape Verde Islands. Some slow development of this system is
possible over the next several days while it moves westward at about
15 mph. This system could still bring locally heavy rain and gusty
winds in squalls to portions of the Cape Verde Islands today.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...medium...30 percent.

$$
Forecaster Kimberlain

[Nimbus]

Global Hawk UAV is on the way to 90L:
http://airbornescience.nasa.gov/tracker/

It left Virginia at around 7am EDT for a 25 hour flight.

From yesterday's mission schedule:
"AV-6 to fly Science Flight #4 tomorrow (target I90L/P27L off African coast; 60 sondes loaded)."
https://espo.nasa.gov/missions/hs3/daily-schedule

From NHC's Plan of the Day:

Code: Select all

    3. REMARKS: GLOBAL HAWK NASA872 WILL DO A TROPICAL
       WAVE/ SAHARA DUST INTERACTION RESEARCH FLIGHT DEPARTING
       KWAL AT 05/1100Z. FLIGHT LEVEL 55,000 TO 62,000 FT.
       DURATION: 05/1100Z TO 06/1200Z. 60 SONDES TOTAL-           
       RACE TRACK PATTERN WITHIN BOX ORIENTED N TO S WILL           
       BE FLOWN FROM W TO E IN REGION BOUNDED BY:
        A. 17.48N 30.17W
        B. 9.50N 30.16W
        C. 9.50N 23.91W
        D. 17.48N 23.91W

Global hawk that would be one of these?

http://www.freedomfiles.org/war/globalhawkaa.jpg

Wonder how much the rail birds have to pay for that fancy landing gear?

[Bizzles]

Do we know what time the UAV will reach the target area?

Pretty cool they can send recon to something that far away!

[cycloneye]

12z Best Track:

AL, 90, 2014090512, , BEST, 0, 130N, 241W, 20, 1009, DB

[Chris_in_Tampa]

Do we know what time the UAV will reach the target area?

I don't know the flight path, but drawing a straight line using the speed over one hour it could be something like this kind of timetable:


I don't know where they will go first.

[Sanibel]

SAL appears to be getting the upper hand.

[cycloneye]

SAL appears to be getting the upper hand.

At least 90L has been fighting the sal and cleaning things for wave behind.

[gatorcane]

Latest, saved vis image:

[Ntxw]

its about to hit the wall of sinking air, big supressed KW look at the cloud formations to its west.

[AEWspotter]

I have to disagree with some of the comments about the air mass being too dry for 90L. The environment is certainly drier ahead of the system, but right now, it's embedded in a pocket of ~60mm total precipitable water. You can see from this RAMMB product that while some drier air has wrapped around the system, the TPW in this "Dry wrap" are still above 37 mm.

On the topic of vertical wind shear, I'm not sure what Dr. Masters was talking about last night. While SHIPS (Statistical Hurricane Intensity Prediction Scheme) is a statistical model, it is an excellent indicator of what the large-scale environment of a system will be. For the last 24 hours, SHIPS has consistently forecast shear values under 15kts. If you look at the adjusted shear (which takes into account storm motion), the shear is almost negligible. There is some suggestion that moisture in the environment will be an issue 48 hour out, but if this system has already developed, that won't be an issue. For the record, SHIPS brings 90L to hurricane status at 84 hours at 17N,45W.

RAMMB TPW


SHIPS: http://www.ral.ucar.edu/hurricanes/real ... _ships.txt

[AEWspotter]

I should add that if 90L doesn't develop in the next 24-48 hours, the TPW that is currently associated with it will slowly dwindle. So my UNOFFICIAL forecast is that it either develops by 30W or it will have to wait until it's past 50W. Quite a narrow forecast, eh?

[Alyono]

SAL appears to be getting the upper hand.

At least 90L has been fighting the sal and cleaning things for wave behind.

the wave behind is likely already dead. Another large SAL outbreak appears to be moving off of the coast now. It will be embedded within the next SAL outbreak

[YoshiMike]

Well that means safer people if you are correct

[Hurricane_Luis]

Do we know what time the UAV will reach the target area?

I don't know the flight path, but drawing a straight line using the speed over one hour it could be something like this kind of timetable:

http://i.imgur.com/R6rVNbd.jpg
I don't know where they will go first.

Wow. I guess they have already left. Looks like they have chosen the longest possible route. Wonder why they never took off from US.V.I
of Puerto Rico.

[Chris_in_Tampa]

Wow. I guess they have already left. Looks like they have chosen the longest possible route. Wonder why they never took off from US.V.I
of Puerto Rico.

It's about half way across the Atlantic right now. Probably four to five hours to go.

It's a big research project, so their home base is at NASA's Wallops Flight Facility. Everything is setup for the aircraft:
https://espo.nasa.gov/missions/hs3/cont ... uts_-_2014