Tropical Storm Bertha Model Runs

[GeneratorPower]

Please learn to use the PMs instead of the personal back and forths in open forum

[MiamiensisWx]

The following post is NOT an official prognosis.

It honestly looks like the upper level ridge is already building west as the TUTT quickly lifts out of the area. Note that Bertha's forward movement during tomorrow and the next few days is going to exert some significant influences in regards to its track. Currently, a shortwave trough at H5 is moving east from the Ohio Valley to the Mid-Atlantic region. Water vapor imagery of the upper levels indicates the shortwave trough is moving rather rapidly to the east as the weak H5 vort max transects the area. The fast northern stream suggests the shortwave trough will exit the Mid-Atlantic fairly quickly, allowing the upper level ridge to H5 to re-assert itself and briefly build to the west. This trend may likely commence as soon as tomorrow and the following day. If you combine the unfolding current situation with an extrapolation of Bertha's ongoing rapid movement, it could indicate that Bertha may be closer to the CONUS earlier than some people anticipate. Bertha has been persistently moving further west faster than expected over the past ~24-36 hours. I highly doubt that Bertha will only come within a certain distance of the CONUS by late next week. After analysis of current trends and the pattern, it appears that it may occur earlier than that time frame. Depending on the timing of the next H5 trough progged to affect the East and the amplification of the upper ridge in the West, Bertha could certainly pose a threat to the Southeast (primarily North Carolina).

One possible concern in regards to the intensity is the fact that a small upper low NE of Bermuda is moving SSE as the TUTT moves NE. This new upper low could deepen and develop a new TUTT (the second one progged by the operational GFS at 200-250 mb?) over the next few days in a similar position to the current TUTT. This could increase the upper level divergence/shear in the vicinity north of the Leeward Islands and Puerto Rico. Therefore, after gradual intensification, Bertha's intensity could fluctuate in that area. That leads to the possibility of a more southerly and westerly track in the long range, depending on the actual intensity of Bertha at that time and the degree of the possible TUTT's influence.

I'm not a person who casually ignores or disputes models, especially if they are latching on to a pattern. I also regularly utilize climatology in my analysis. However, based on all available evidence, I believe it is premature to sound the all clear for the Southeast. It is also premature to make a definite statement that Bertha will strike the CONUS, Bermuda, the NE Caribbean, or any land mass. Both approaches should be discouraged, especially given the considerable uncertainties and complexities involved. Everyone should be prepared, regardless of their location. The evolution of this system, the analysis of the models, and the "kinks" thrown in to the synoptic pattern will present an exceptionally fascinating and extremely intriguing situation. Regardless of the final result, Bertha will present an incredibly tough forecasting challenge and a bastion of knowledge for everyone involved. This system has already been impressive itself.

Bump for constructive "on topic" discussion

['CaneFreak]

Please learn to use the PMs instead of the personal back and forths in open forum

Oh, since when have you become a moderator? I don't see moderator beside your name.

[cycloneye]

Are we going to talk about other members or about the theme of this thread,model runs?

[SouthFloridawx]

You guys are sooo hilarious.
Since when did you become comedians?

:uarrow: Ok lets cut it there,both.

huh? im confused

I am too actually.....

[MGC]

Just read the 11pm discussion. NHC discussed the large divergence in model guidiance, near 1300 miles. I am not surprised considering the lack of upper air data. The models are making an educated guess at the status of the atmosphere out over the Atlantic Ocean. With Bertha continueing to treck along to the west at 18KTS I'd conclude that the ridge that is stearing Bertha is strong. I've seen the models recurve a system when in fact Mother nature has different plans. Does anyone know if or when the Gulfstream is going to sample the upper atmosphere ahead of Bertha? Though I think Bertha will pass north of the Antillies, the Bahamas and possibly the EC might be at slight risk at this time.....MGC

[cycloneye]

Nobody talks about the NAM model so here is the 00z run.

[cycloneye]

Just read the 11pm discussion. NHC discussed the large divergence in model guidiance, near 1300 miles. I am not surprised considering the lack of upper air data. The models are making an educated guess at the status of the atmosphere out over the Atlantic Ocean. With Bertha continueing to treck along to the west at 18KTS I'd conclude that the ridge that is stearing Bertha is strong. I've seen the models recurve a system when in fact Mother nature has different plans. Does anyone know if or when the Gulfstream is going to sample the upper atmosphere ahead of Bertha? Though I think Bertha will pass north of the Antillies, the Bahamas and possibly the EC might be at slight risk at this time.....MGC

And Bermuda has to be added to the equation.

[MGC]

Why thanks Cyclone, I forget to mention Bermuda. Bertha is going to be an interesting TC to figure out where she is headed.....MGC

[gotoman38]

I think the earliest we might see recon on this storm is Tues AM -

FORECAST VALID 08/0000Z 19.6N 53.7W

that's about 640 nm from St Croix - I'm guessing they would wait to get within 500 nm to make the run.

Think we might see a TCPOD on Monday morning for a run from STX to BERTHA?

[Stratosphere747]

Remember when talking about recon there is a difference between the HH missions and the NOAA flights.

[gotoman38]

Remember when talking about recon there is a difference between the HH missions and the NOAA flights.

Ah yes - do you think they would send the Gulfstream out sooner?

[JonathanBelles]

GFS is rolling

[MGC]

They should send the Gulfstream out is there is a risk to land. I just checked the plan of the day on the NHC site and there is no recon scheduled. I would imagine they will fly it when it is a few hundred miles away from land......MGC

[GeneratorPower]

Anybody know why the NAM is pretty much ignored for tropical weather?

[NDG]

0z gfs looks to have a better handle on Bertha (track & speed) than the 18z run

[cycloneye]

They should send the Gulfstream out is there is a risk to land. I just checked the plan of the day on the NHC site and there is no recon scheduled. I would imagine they will fly it when it is a few hundred miles away from land......MGC

The best person that will answer about when a plane will be available to fly into Bertha is one of our members (pojo) who is part of the crew that is assigned to a mission.

[Derek Ortt]

The G-IV flies out of Tampa, not Keesler

[LarryWx]

Anybody know why the NAM is pretty much ignored for tropical weather?

I think it is because it has done terribly overall in the tropics. I pretty much ignore it myself.
I feel it is awful for tropical features. Not only does it constantly forecast phantom storms (similarly to the Canadian), but it also has done poorly overall on existing storms' tracks imho.

[gotoman38]

The G-IV flies out of Tampa, not Keesler

I know that the HHers relocate to STX for the long trackers - do the G IVs do something similar, or do they use their speed to strike from Tampa?