ATL: IRMA - Models

[TheStormExpert]

Ridge starting to weaken @144hrs.

[ColdMiser123]

Euro now moving due west at hour 150.

Side note, looks like it is trying to develop a low in the BOC. A few GFS Ensembles hinted at this happening.

[SouthFLTropics]

That ridge isn't budging anytime soon...And worse, Texas seems to be getting inundated AGAIN at hour 144 along with something else trying to spin up in the BOC. Crazy!!!

[sma10]

FWIW, in the 144hr range, excellent agreement in strength and placement between Euro/Uk at around 17-18N 50W

[chaser1]

I beg to differ with you'all. While comparing the 12Z yesterday to today's 12Z, and looking at their respective 12Z Saturday verification times.... here is what I see. Today's run implies that Irma will be stronger than the prior EURO's comparative run. Also, if using the same Sat. 12Z verification time and comparing today's 12Z 96 hr. run to the 12 Z run from yesterday, this newest run places Irma at about 19.2 N and 41.0 W (as compared to the prior EURO 120 hr 12Z run where it would have been centered at 18.5 N & 45.6 W for the same verifying time period of 12Z Sat.). We're talking about a 1/2 degree difference in greater latitude and about 4 =/- degrees longitude. The synoptic set up is no different however and there is no reason that Irma should then suddenly go out to sea?? In fact, this is where the Atlantic High really begins to exert itself and where Irma begins a WSW motion I believe.

[ace]

Heres a link to the GFS from this a.m.
http://www.tropicaltidbits.com/analysis/models/

There looks to a new surge of energy entering the BOC in about 72 hr's. At 110 hrs pressures appear to drop throughout the W. Gulf. Somewhere around 210 hr.s was where I noticed a tropical system beginning to take shape. Remember.... it's the GFS so don't overly focus on the details as much as the potential trend

Got it! Thank you!

[meriland29]

That ridge isn't budging anytime soon...And worse, Texas seems to be getting inundated AGAIN at hour 144 along with something else trying to spin up in the BOC. Crazy!!!

Let's not panic quite yet about Texas getting hit with something else in a week. It is far, far too soon to take any model right now to the grave. I try not to focus on models until 3-4 days out only cause wide variations consolidate into a smaller variations the more time passes. That being said, I 'try' but it is hard not to watch this from beginning to end.

[jlauderdal]

That ridge isn't budging anytime soon...And worse, Texas seems to be getting inundated AGAIN at hour 144 along with something else trying to spin up in the BOC. Crazy!!!

Bastardi likes the western gulf next week

[AutoPenalti]

I beg to differ with you'all. While comparing the 12Z yesterday to today's 12Z, and looking at their respective 12Z Saturday verification times.... here is what I see. Today's run implies that Irma will be stronger than the prior EURO's comparative run. Also, if using the same Sat. 12Z verification time and comparing today's 12Z 96 hr. run to the 12 Z run from yesterday, this newest run places Irma at about 19.2 N and 41.0 W (as compared to the prior EURO 120 hr 12Z run where it would have been centered at 18.5 N & 45.6 W for the same verifying time period of 12Z Sat.). We're talking about a 1/2 degree difference in greater latitude and about 4 =/- degrees longitude. The synoptic set up is no different however and there is no reason that Irma should then suddenly go out to sea?? In fact, this is where the Atlantic High really begins to exert itself and where Irma begins a WSW motion I believe.

Hour 144 is where it's stuck, ridge seems weaker at that timeframe. Let's see what happens.

[TheStormExpert]

Moving due west @168hrs. Off topic, look at what is heading for the NW Gulf and Texas again!

[chaser1]

Just realized I was slow in my last post and in fact I was correct...... Irma is NOT racing to the North Pole LOL!! Not to say that downstream troughing near or close to the E. Conus might not veer her east of the Bahamas and the US but that's an altogether another topic for farther down the road.

[TheStormExpert]

12z Euro @192hrs.

[chaser1]

Lets see if the 216 hr. 500mb remains consistant with prior run showing 600mb heights building north of Irma with time! New added wrinkle of course is the "latest" GOM invader taking aim at Louisiana.

[sma10]

More of a WNW heading at 192hr, passing the Leewards to the NE. This is where these suckers usually find their escape hatch, however from the look of that trough digging into the nation's midsection, I don't see a clear escape route yet.

[AutoPenalti]

12z Euro @192hrs.

May I ask what the difference is between the MSLP anomaly, 500mb and the 500mb normalized anomaly?

[TheStormExpert]

12z Euro @216hrs.

[chaser1]

500mb is the forecast of the basic steering level, where the 500mb anomoly is the present 500mb forecast as compared to multi-year average 500mb over time. I like to compare the 500mb maps to the 500mb 24 hour change

[AxaltaRacing24]

12z Euro @192hrs.

May I ask what the difference is between the MSLP anomaly, 500mb and the 500mb normalized anomaly?

MSLP anomaly is mainly for seeing what the ocean pressures are, if they are decreasing or increasing, storm intensity, and if they are above or below normal in a certain area.
500mb normalized anomaly is for depicting the strength of ridges and troughs, which can help us determine where a system is going to go due to since those features steer the cyclones.

[blp]

Looks like the trough is getting squeezed with the big Bermuda High from the East and the High out to the West. If the trough retrogrades watch out this thing is heading west.

[meriland29]

Is there a reason we are already seeing so much activity this year? Is it cause El Nino came and went? Warmer waters? I am just curious on opinions,.