2021 Tropical Waves Thread

[USTropics]

00z CMC with a low rider into the Caribbean:

[Stormybajan]

As much as it wants to goes west, the windshear really isnt letting up. Im fairly certain the convection associated with this wave has been stuck at 55-56 west for HOURS. Wonder what we will find in the morning

[hurricanes1234]

00z CMC with a low rider into the Caribbean:

https://s6.gifyu.com/images/gem_z850_vort_atl_fh0-240.gif

Geez that run shows it basically brushing T&T towards the end. Still way too far out to know anything for sure but it sounds like this system is gonna stay low in latitude so I'll be watching things closely from down here.

[Kingarabian]

00z Euro through 72 hours keeping it an open wave so far:

[Ubuntwo]

00z through 72 hours keeping it an open wave so far:
https://i.imgur.com/JUdceyc.png

TT's intervals are too coarse to show this, but the system gets flung north off Africa to ~14N before quickly dying off. At those latitudes by the African coast waters are around 24C so far too cold for tropical development. The 12z run settled it at around 10-11N where SSTs are much more manageable, hence development. Something to watch moving forward.

[JRD]

Midlevel vortex forecast in 48 h by GFS. Initially it'll be symmetric with a shallow cold core (meaning a warm core on top of the cold core), which is a common configuration for cyclones in the tropical Atlantic. The model sees it turning into at least a tropical depression if not Danny (indicated by its transition to a symmetric moderately warm cyclone). Lots of things (such as the model trajectory) can change though.

[chaser1]

Anyone happen to post or reference the UK model for either wave yet?

[Kingarabian]

Anyone happen to post or reference the UK model for either wave yet?

No development yet.

[Shell Mound]

00z GFS jumping on board with a tiny core system traversing the MDR:

https://s6.gifyu.com/images/gfs_z850_vort_atl_fh0-150.gif

Meanwhile, the 00Z EPS has become quite bearish vs. yesterday’s 12Z, with only a handful of members showing development. (No hurricanes are shown.)

[SconnieCane]

00z GFS jumping on board with a tiny core system traversing the MDR:

https://s6.gifyu.com/images/gfs_z850_vort_atl_fh0-150.gif

Meanwhile, the 00Z EPS has become quite bearish vs. yesterday’s 12Z, with only a handful of members showing development. (No hurricanes are shown.)

Maybe someone showed it a calendar.

[Shell Mound]

ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Thu Jun 24 2021

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. Disorganized shower and thunderstorm activity continues to the east
of a small area of low pressure located about 200 miles east of
Barbados. Increasing upper-level winds are likely to prevent
further development of this system during the next couple of days
while it moves west-northwestward at about 10 mph. This disturbance
could produce increased shower activity and some gusty winds when it
moves across the Lesser Antilles on Friday.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...10 percent.

[Shell Mound]

00z GFS jumping on board with a tiny core system traversing the MDR:

https://s6.gifyu.com/images/gfs_z850_vort_atl_fh0-150.gif

Meanwhile, the 00Z EPS has become quite bearish vs. yesterday’s 12Z, with only a handful of members showing development. (No hurricanes are shown.)

Maybe someone showed it a calendar.

Why is there such a difference between yesterday’s 12Z and today’s 00Z suites? Conditions and positions do not seem to differ significantly. (Unsurprisingly, just as the 00Z EPS has trended toward a bearish solution vs. 12Z, the 00Z GEFS has trended toward a bullish solution vs. 12Z. Many more 00Z GEFS members show development vs. yesterday’s 12Z. Why do EPS and GEFS solutions seem to be inversely correlated with each other?)

[tolakram]

Why is there such a difference between yesterday’s 12Z and today’s 00Z suites? Conditions and positions do not seem to differ significantly. (Unsurprisingly, just as the 00Z EPS has trended toward a bearish solution vs. 12Z, the 00Z GEFS has trended toward a bullish solution vs. 12Z. Many more 00Z GEFS members show development vs. yesterday’s 12Z. Why do EPS and GEFS solutions seem to be inversely correlated with each other?)

Simple, it moves the wave too far north over much cooler waters. Those waters are still normal for this time of year, but exactly why we don't expect CV systems this early. We'll see, but this reminds me of euro performance in the Gulf early in the season where it constantly fails to correctly predict development and direction due to sub-par conditions. If the Euro is wrong about the wave moving further north then yesterdays solution was correct, otherwise it won't develop much. In my opinion.

[tolakram]

Still a bit early but it appears to be steady, similar to last night.

https://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=full_disk&x=14088.349609375&y=8380.65673828125&z=3&angle=0&im=12&ts=1&st=0&et=0&speed=130&motion=loop&maps%5Bborders%5D=white&lat=0&p%5B0%5D=band_02&opacity%5B0%5D=1&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&draw_color=FFD700&draw_width=6

[tolakram]

Daily SST snapshot. Not a lot of wiggle room.

[Aric Dunn]

Thank God the convection died .. lol don't know if I could stand reading another TWO at 10% on it.

[wxman57]

I'm not concerned about this disturbance. It had an exposed LLC west of the convection yesterday, but wind shear is ripping it apart. It may bring some moisture to the western Gulf late next week, but development appears unlikely.

[ouragans]

Should be an invest soon

2. A strong tropical wave has emerged just off the coast of Africa this morning. Although ocean temperatures are still relatively cool over the tropical Atlantic Ocean and are only marginally conducive for development, a small tropical depression could form by early next week while this system moves westward to west-northwestward at about 15 mph across the tropical eastern and central Atlantic Ocean.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...medium...40 percent

[wxman57]

This wave's best chance of development will be over the next 2-4 days. Beyond then, it runs into increasing wind shear as it approaches the eastern Caribbean next Wednesday. The MDR is still quite hostile toward development so early in the season.

On the other hand, the TPW loop indicates it is weaker than yesterday. Very little rotation now.

http://tropic.ssec.wisc.edu/real-time/mtpw2/product.php?color_type=tpw_nrl_colors&prod=natl&timespan=72hrs&anim=html5

[Aric Dunn]

Strong Mid level Circ and Good Low level Curvature. Wont take long to close off if convection maintains. that MLC is at 3N just as an FYI lol