Strong SAL outbreak

[ninel conde]

nothing impressive over africa. i wonder how many augusts had no named storms.

[ronjon]

I dunno not many but that won't be the case this August. Things starting to round into shape for the cape verde season. Look at the WV loop, huge area of moisture almost up to 20 N across the eastern atlantic.

http://www.ssd.noaa.gov/eumet/eatl/loop-wv.html

[tolakram]

For those of you fretting over the SAL outbreak, there's a very good piece of research available online.

From the Wikipedia entry on SAL: http://en.wikipedia.org/wiki/Saharan_Air_Layer

this research paper: http://journals.ametsoc.org/doi/pdf/10. ... S-85-3-353

SAL catches up to storms, not the other way around. So conditions behind this outbreak are unknown.

[HURAKAN]

latest

[HURAKAN]

WU

[cycloneye]

https://fbcdn-sphotos-e-a.akamaihd.net/hphotos-ak-frc3/1073958_10200356239008990_846720336_o.jpg

latest

Not as thick as on Tuesday but still strong.

[StormTracker]

I've seen some posts asking what SAL is and how it can affect tropical cyclones, so here is a little info on the matter. Notice "Erin" in the top pic? Could Erin 2013 possibly get caught up in the SAL the same way as his predecessor??? Hmmm...

The SAL and (top) 2001 Erin (middle) Helene 2006, and (bottom) Bill 2009
Contributed by Jason Dunion

The Saharan Air Layer (SAL) is a mass of very dry, dusty air which forms over the Sahara Desert during the late spring, summer, and early fall and usually moves out over the tropical North Atlantic Ocean every 3-5 days. The SAL extends between ~5,000-20,000 ft (~1500-6000 m) in the atmosphere and is associated with large amounts of mineral dust, dry air (~50% less moisture than a typical moist tropical sounding), and strong winds (~25-55 mph or ~10-25 m/s). These strong winds, or jets, are usually found between 6,500-14,500 ft (2000-4500 m) above the surface in the central and western North Atlantic and have a depth of ~1-2 miles (~1.6-3.2 km).

The SAL can have a significant negative impact on tropical cyclone intensity and formation. Its dry air can act to weaken a tropical cyclone by promoting downdrafts around the storm, while its strong winds can substantially increase the vertical wind shear in and around the storm environment. It is not yet clear what effect the SAL's dust has on tropical cyclone intensity, though some recent studies have suggested that it can actually impact the formation of clouds.

The SAL can cover an area the size of the continental U.S. and has been tracked as far west as the Caribbean Sea, Central America, and the Gulf of Mexico. Real-time satellite imagery for tracking the SAL can be found here.

References:
NOAA Hurricane Research Division
•Dunion, J.P., and C.S. Velden, 2004: The impact of the Saharan Air Layer on Atlantic tropical cyclone activity. Bull. Amer. Meteor. Soc., vol. 85 no. 3, 353-365.

[HURAKAN]

Not cloudy, DUSTY! Saharan dust affecting the Canary Islands

http://www.azarugsurfhouse.com/index.html

[StormTracker]

That can't be good on the eyes, respiratory system, nothing! That's just downright nasty! They probably pray for a system or two to miraculously come their way to clear the air! It's bad enough when we get it all the way over here!

[Bocadude85]

nothing impressive over africa. i wonder how many augusts had no named storms.

As far as I know the answer is two 1961 & 1997. 1961 had seven major hurricanes though so a quiet August does not mean a quiet season, and 1997 featured a strong El Nino.

[Hybridstorm_November2001]

nothing impressive over africa. i wonder how many augusts had no named storms.

As far as I know the answer is two 1961 & 1997. 1961 had seven major hurricanes though so a quiet August does not mean a quiet season, and 1997 featured a strong El Nino.

Strange tidbit Princess Diana was born during a hurricane season (July 1st 1961) with no August named storms & died in a season with no August named storms (August 31st 1997).

[tolakram]

This updating loop of the SAL demonstrates how fast it moves. See how it's passing up the wave at 30W?

http://tropic.ssec.wisc.edu/real-time/s ... litE5.html

[Kingarabian]

[Yellow Evan]

nothing impressive over africa. i wonder how many augusts had no named storms.

As far as I know the answer is two 1961 & 1997. 1961 had seven major hurricanes though so a quiet August does not mean a quiet season, and 1997 featured a strong El Nino.

1914 AHS? It's only storm was in September IIRC.

[RL3AO]

nothing impressive over africa. i wonder how many augusts had no named storms.

As far as I know the answer is two 1961 & 1997. 1961 had seven major hurricanes though so a quiet August does not mean a quiet season, and 1997 featured a strong El Nino.

1914 AHS? It's only storm was in September IIRC.

I ignore anything before 1950 or so. Too many holes in the data.

[Alyono]

nothing impressive over africa. i wonder how many augusts had no named storms.

truth be told, these season over posts are getting a bit annoying. It is still July and we have had 2 storms in the MDR this month. How many Julys have this?

[Hurricaneman]

nothing impressive over africa. i wonder how many augusts had no named storms.

truth be told, these season over posts are getting a bit annoying. It is still July and we have had 2 storms in the MDR this month. How many Julys have this?

It looks like people are expecting all July's to be like 2005 which couldn't be further from the truth. July's have an average of less than 1 storm a year so development shouldn't really be expected in July but if we get to mid August and there's nothing on the horizon than it may be slow from there on out, but even if its slow from that point doesn't mean a deadly storm can't pop like an Andrew which happened in a slow season or even a Bob like storm in the NEUS

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

[southerngale]

[abajan]

If memory serves me correctly, back in the 1980s the islands of the eastern Caribbean had periods with very thick Sahara dust. There were days when one could hardly see the sun and we had to be constantly cleaning thick brown dust from our cars. I doubt this outbreak will be anything like that.

[Hurricane Alexis]

It appears that the next wave rolling off Africa is moistening up the environment and that the worst of the outbreak has ended.