2013 Steering Pattern / Early indicators

[TropicalAnalystwx13]

The MJO is single-handedly the largest intraseasonal variable we have to predict tropical cyclogenesis. July still falls under the "early season" category, meaning it's very tough to get development without it. As we head into August and September, it remains a very large factor, but is not necessary for the formation of tropical cyclones because atmospheric conditions are now favorable.

[TheStormExpert]

I think the answer to most questions concerning favorability is JULY.

July is normally a slow month. No more fronts to help spawn storms and we're not in the meat of the season yet.

July is basically a transitioning month because of the stated above. TS Chantal formed in the MDR which climatology does not see storms develop in that area until almost the middle of August when things really start picking up. Overall we are above average with total number of storms so far, and on average shouldn't see are first hurricane until the first half of August. Remember last July? No storms at all then came August 1st and bam we had Ernesto form right away!

[Cyclenall]

Imagine that ECMWF also has high pressures in EPAC. Also no season there.

I was just going to say that, that image is totally absurd. I have no way of envisioning something resembling that from the Euro. Both the Atlantic and Epac hurricane seasons would cease to have any tropical cyclone activity on an order worse than a strong El Nino (for the Atlantic) and La Nina (for Epac). It would be completely unprecedented (find a year where both the Atlantic and Epac had nothing after July at the same time) and embarrass the entire weather community to a point where no one would ever listen again to forecast numbers. I would pretty much stop following the tropics permanently if it were to verify .

no wonder joe bastardi isnt excited. alot of forecasts are going to be dumped soon. high pressure and dry air. we may be looking at another 1994 or 1967. does anyone have the whole US forecast? i can only see part of it. i ask because bastardi is saying summer is over after this week, but it appears pressures are higher than normal in all of the US i can see.

I notice 100% of what JB says is the exact opposite of what I want. I'm never worried though .

And JB is trustworthy why...?

Thanks.

Hmm, that's interesting. Well, who knows, we might get lucky and have a year that has too much shear and dry air for storms to get going, but of course it's way way to early to say for sure...

My ultimate season would be if we had lots of cat 4, cat 5 hurricanes that came close to landfall(just to raise excitement and awareness, but then went out to sea). Those are always fun to watch spin up and track

We already had that, it was called 2011 and 2012 (17 meek systems with 2 not so much). Doesn't look like that much SAL on the maps in my view. Shear? That was every year since 2005. Your ultimate season would actually be the ultimate beach erosion and storm surge season. Still a ton of damage but horribly awful in terms of meteorology. I rather have a hurricane season that had absolutely no activity so I could stop watching completely.

The Ukmet forecast for MSLP across the basins is another reason the Euro is to be discounted. When you have complete opposite forecasts, its obvious not to side with the one that has been getting it wrong for a long while.

[cycloneye]

New video by Levi Cowan about the rest of July and beyond.

http://www.tropicaltidbits.com/blog/201 ... d-of-july/

[TropicalAnalystwx13]

Still thinking this should be a bad year for the United States overall. Ridging over the western Atlantic with troughing over the central United States is never a good pattern.

Given this, any hurricane originating in the East Atlantic and making it to the West Atlantic would make landfall on the Southeast U.S. coastline (North Carolina to Florida). Any system in the Caribbean would be steered northwest and eventually north...likely into the Mississippi-Alabama region.

As usual, however, this pattern could change. In fact, most of the dramatic pattern changes I checked...such as 2010...occurred in early August. Something to watch for.

[cycloneye]

JMA July forecast for ASO has a wet MDR. Levi Cowan tweeted about this.

Levi Cowan ‏@TropicalTidbits 1h
JMA main seasonal forecast out today is wetter than normal in tropical Atlantic for Aug-Sep-Oct. Active pattern.

[BigB0882]

The EURO is looking really off to me this year. Did it undergo an upgrade? Can some upgrades actually cause the model to function with less accuracy or maybe it takes a little while to work out all the kinks?

[gatorcane]

My contribution to the debate here is that it is only mid July - the Atlantic is usually not active during the current time period when you look back through climatology.

Also, I agree with TropicalAnalystwx13 and still forsee the steering patterns will be there for some part of Aug and September to allow Cape Verde systems to make the trek across the Atlantic and possibly threaten the Caribbean islands and the U.S.

I am just not seeing a persistent East Coast trough we have seen the past three seasons during the Aug-Sept timeframe which steered systems away and out into the Atlantic.

We have seen "hints" of just how strong this Bermuda High can be this year when we look at it's strength and location in June where it was abnormally strong and I think it comes back strong again for periods during Aug. and Sept.

[ninel conde]

mr bastardi still harping about dry air.

Joe Bastardi ‏@BigJoeBastardi 7h

Dry air continues to destroy African wave train http://tropic.ssec.wisc.edu/real-time/s ... vmid5.html …

[BigB0882]

I thought we have seen a lot of good waves emerge off of Africa. They don't typically develop in July, anyway. How is this any different than any other year?

[TheStormExpert]

The way it seems we have entered a typical July lull which is usual for this moth in the hurricane season. I would assume that the dry air will start going away in another 2 weeks, also I really do not know what the deal is with the shear. I just noticed that there is a big area of shear just east of the E. Caribbean from 40W-60W up to about 25N, I guess this is still typical for July standards but it seems like there are very few areas of light shear. Which is why the overall Atlantic basin is hostile for any development currently. But normally this is the worst period for development in July I guess, and things should start changing in about 2 weeks.

[ninel conde]

I thought we have seen a lot of good waves emerge off of Africa. They don't typically develop in July, anyway. How is this any different than any other year?

just observing joe bastardi it seems he is now finding reasons why the season wont be so big. i cant remember and gung ho posts from him since his awful tweet about a hyper active july. really, nobody is particualry gung ho anymore.

[CYCLONE MIKE]

Doesn't the nhc, guys over at Colorado state and others put out a revised forecast come first or middle of august? Really interested if forecast will be revised downward or not.

[ninel conde]

Doesn't the nhc and guys over at Colorado state put out a revised forecast come first or middle of august? Really interested if forecast will be revised downward or not.

yes, dr gray puts out an aug update.

[cycloneye]

Doesn't the nhc, guys over at Colorado state and others put out a revised forecast come first or middle of august? Really interested if forecast will be revised downward or not.

They will release on August 2nd.

[Hurricaneman]

The way it seems we have entered a typical July lull which is usual for this moth in the hurricane season. I would assume that the dry air will start going away in another 2 weeks, also I really do not know what the deal is with the shear. I just noticed that there is a big area of shear just east of the E. Caribbean from 40W-60W up to about 25N, I guess this is still typical for July standards but it seems like there are very few areas of light shear. Which is why the overall Atlantic basin is hostile for any development currently. But normally this is the worst period for development in July I guess, and things should start changing in about 2 weeks.

I agree, this is common for July and there is no reason to cancel the season as of now my opinion is the last week of July to first week of August is when things will start to be favorable

[TropicalAnalystwx13]

CSU is going to lower their numbers simply because they were too high to start with. 18 named storms in the deep tropics was probably never going to happen. I forecast the same number several months ago, taking into consideration a few frontal/subtropical cyclones (that haven't materialized because of this high pressure!). A 14-15 named storm year looks likely.

[ninel conde]

CSU is going to lower their numbers simply because they were too high to start with. 18 named storms in the deep tropics was probably never going to happen. I forecast the same number several months ago, taking into consideration a few frontal/subtropical cyclones (that haven't materialized because of this high pressure!). A 14-15 named storm year looks likely.

the worrisome thing im seeing is the high way too far south. im also now seeing the possibility of the neg nao returning.

[TreasureIslandFLGal]

Every year there is all this talk about season being "boring"and numbers needing to revise down in July. July is usually a very slow month. The potential early genesis from fronts digging deep stop and the cape verde systems are still a few weeks away from being ready to take their trek. This part of the year, the shear is always high and makes it difficult for anything of significance to form just before the islands, or tears apart anything that managed to develop early and cross the Atlantic. In fact, it all seems extremely typical to me right now. We just have to wait a few more weeks.
What does seem unusal is that there is quite a low level of SAL compared to recent years at this point, and also that the ridge is quite strong and looks to be setting up in a dangerous position compared with the last few years. It has been a very rainy July for us on west coast Florida, withflow often coming from teh south.--that isn't very common, and provides all day rain chances, vs. our typical afternoon only pattern. That means the ridge's western periphy is pretty much over us, directing flow clockwise around it, so tapping into teh deep tropical moisture and sending it up towards us. -which would also tend to steer atlantic crossers into Florida that were following the periphery.
Obviously still early season, and this can very well change by the heart of hurricane season. --let's hope so.

[ninel conde]

the SAL is a puzzler. it hasnt been that terrible but things are dried up anyway. maybe mr bastardi is right saying the 400 mb will be too dry this season.

http://tropic.ssec.wisc.edu/real-time/s ... plitE&time

except for a small blob over central africa the tropics are totally devoid of convection from 65 west eastward across africa.