ATL: IRMA - Models

[TheStormExpert]

Is that an ULL to the NW of Irma? If so wouldn't that likely help to weaken the ridge allowing for a escape route OTS?

That Upper trough is the key player in this entire game.

Euro has it much further west than GFS

Yeah 00z Euro already has it NE of the Southeast Bahamas @5days.

[SouthFLTropics]

The pattern progression from the Pacific across North America is about 3 to 4 degrees behind the 06z.

[sma10]

This run will almost surely be a recurve. GFS doesn't dip nearly as much as Euro.

[ronjon]

500 mb pattern from the GFS looks like a classic Omega Block.

[RL3AO]

You'll see the trough over the great lakes amplify in the next few frames. The Atlantic ridge will then amplify about 24 hours later. Classic Rossby wave train moving across the NH.

[SouthFLTropics]

This run will almost surely be a recurve. GFS doesn't dip nearly as much as Euro.

I wouldn't be so sure of that. The pattern shown on the 500mb continues to favor a westward motion. Let's see how the 500mb pattern progresses across the CONUS with time.

[forecasterjack]

You'll see the trough over the great lakes amplify in the next few frames. The Atlantic ridge will then amplify about 24 hours later. Classic Rossby wave train moving across the NH.

That RW influence from the Typhoon is driving the WSW motion correct?

[TheStormExpert]

 https://twitter.com/TropicalTidbits/status/902869681400360961

[sma10]

Also note the strengthening Tropical Storm heading north towards the Texas coast.

[ronjon]

You'll see the trough over the great lakes amplify in the next few frames. The Atlantic ridge will then amplify about 24 hours later. Classic Rossby wave train moving across the NH.

The key in the long-range is does that trough retrograde west, remain stationary, or erode the ridge to the east over time.

[SouthFLTropics]

You'll see the trough over the great lakes amplify in the next few frames. The Atlantic ridge will then amplify about 24 hours later. Classic Rossby wave train moving across the NH.

That RW influence from the Typhoon is driving the WSW motion correct?

I believe the typhoon may influence the steering as Irma approaches the Bahamas. This run the progression of the recurving typhoon is further west so that may have implications downstream. I'll let RL3A0 chime in further since he's the expert on this.

[TheStormExpert]

You'll see the trough over the great lakes amplify in the next few frames. The Atlantic ridge will then amplify about 24 hours later. Classic Rossby wave train moving across the NH.

The key in the long-range is does that trough retrograde west, remain stationary, or erode the ridge to the east over time.

Also where and how strong is that ULL to the NW of Irma. That will depend where the ridge setups shop determining how far west Irma can get before recurving.

[AxaltaRacing24]

Also note the strengthening Tropical Storm heading north towards the Texas coast.

We need that to not happen

[SFLcane]

Looks to be heading NW-WNW might not even make it to the islands before recurving on this run

[sma10]

This run will almost surely be a recurve. GFS doesn't dip nearly as much as Euro.

I wouldn't be so sure of that. The pattern shown on the 500mb continues to favor a westward motion. Let's see how the 500mb pattern progresses across the CONUS with time.

Perhaps, but the track has a noticeable northward component well east of the islands.

[SouthFLTropics]

162 Hours

[TheStormExpert]

Escape route opening @162hrs.

[SFLcane]

Trap door wide open this should recurve easily we shall see

[SouthFLTropics]

Oh the irony that the tropics bring. Ironically the possible tropical storm near the Texas coast might merge with the trough and help erode the ridge to send Irma out to sea. Let's see how this plays out.

[Siker]

UKMET further south and stronger: TROPICAL STORM IRMA ANALYSED POSITION : 16.5N 29.8W

ATCF IDENTIFIER : AL112017

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 30.08.2017 0 16.5N 29.8W 1009 26
0000UTC 31.08.2017 12 16.5N 31.4W 1008 27
1200UTC 31.08.2017 24 17.2N 33.5W 1007 30
0000UTC 01.09.2017 36 17.6N 35.1W 1006 30
1200UTC 01.09.2017 48 18.5N 36.8W 1006 33
0000UTC 02.09.2017 60 19.2N 39.1W 1007 34
1200UTC 02.09.2017 72 19.4N 42.0W 1004 38
0000UTC 03.09.2017 84 19.1N 44.6W 1001 39
1200UTC 03.09.2017 96 18.3N 47.1W 996 42
0000UTC 04.09.2017 108 17.5N 49.2W 989 57
1200UTC 04.09.2017 120 17.2N 51.1W 984 64
0000UTC 05.09.2017 132 17.4N 53.6W 977 65
1200UTC 05.09.2017 144 17.5N 56.4W 970 68