#91E

Invest #91E has a typical elongated circulation as it develops within the monsoon trough, but will soon pinch off and become more symmetric. Environmental conditions favor intensification for the next few days. pic.twitter.com/PmOM9uHTKP

The EURO model and some (8) of its ensembles (0Z run today shown here) take this system towards the W/NW Gulf by next weekend. Definitely some mischief we can’t take our off of. #91E #tropicspic.twitter.com/jLnc2XIzFR

Currently no active tropical cyclones anywhere around the globe. Next area being monitored for potential tropical cyclone development is a disturbance off of the west coast of Nicaragua. NOAA gives it a 50% chance of formation in next 5 days. #91E #hurricanepic.twitter.com/VuKnqzmzvP

#91E has a 90/90 chance of forming now, and it is quite possible that we will have Blanca by tonight. The thermodynamic is conducive; the moisture and shear seem to be in its favour as well. GFS and CMC don't want anything to do with it, while HMON peaks it at mid-range Cat 2. pic.twitter.com/i9ptD96Yx5

Models continue to show #91E will be in a rather favorable environment with low wind shear, strong outflow, very warm SSTs and a good moisture bubble however there is some very dry air nearby that could try and sneak in so we will see how quickly it can form a inner core. #wxpic.twitter.com/KQB98GegIf

Invest #91E now has an 80% chance of development and advisories could be issued later today if current trends continue. #tropicspic.twitter.com/zPgEkWkC7E

Zooming out on GOES16 global view really illustrates how busy tropics are in the Western Hemisphere. NHC is monitoring *8* areas between EPAC & NATL. Going west-to-east: #91E, #92E, GoM trough, #Sally, #Paulette, #Rene, #95L, #97L No #hurricanes, but Paulette may that soon.pic.twitter.com/agKeXPPguN

Aug 7, 11 am PDT: Satellite images indicate that a broad area of low pressure is forming south of Mexico. A tropical depression is expected to form in 2 or 3 days while the system moves generally west-northwestward, offshore of southwestern Mexico. http://hurricanes.gov  #91E pic.twitter.com/ACrF7JBDhd

Looks like we have got a classic ECMWF vs GFS battle for invest #91E in the EPAC. The euro is noticeably weaker with a weak/moderate TS that is much further NW. The GFS on the other hand has a major hurricane close to making landfall in Mexico. pic.twitter.com/81eK5AlOOy

Obviously will depend on storm structure, but large-scale pieces look favorable for #91E becoming a significant hurricane off of Mexico. Large upper anticyclone with the jet streak with the trough to the NE aiding outflow, moisture from the ITCZ, and warmer than usual SSTs. pic.twitter.com/2ma6Fq7K5F

Invest #91E is just about ready for tropical cyclone classification. One-E failed to become a tropical storm, so #Aletta is up for grabs here. Watching rapid intensification potential--SHIPS indicates 52% shot of 55kt/48hr increase.pic.twitter.com/EngkXPAQbM

#91E is looking very healthy for an invest & we should see a tropical depression tomorrow most likely. Unfortunately, the environment is favorable & a trough will carry this towards E #Mexico as a hurricane. The next name is #Pamela & this could get ugly. #Tropicspic.twitter.com/oFylUcjNwj

Days of #GOES16 visible satellite images showing progression from Invest #91E >> tropical depression >> tropical storm >> #Hurricane #Alettapic.twitter.com/btWMzlfRwp

Invest #91E will bring heavy rain, flash floods and mudslides to portions of Central America and Southern Mexico as it slowly tracks N/NNW. Could still end up in the Southern Gulf next week. Watching this system closely. #tropicspic.twitter.com/dAxaWN2fpX

GFS has an interesting upper-level situation for #91E, where it couples with a large upper-level anticyclone, then proceeds to interact with a strong jet streak to the north. This scenario should allow great ventilation and extremely favorable divergence for intensification. pic.twitter.com/gB7lrpHpw9

A hotly debated topic in tropical meteorology is what constitutes a "monsoon". Are land-sea contrasts key or are they more superfluous? I would argue today's EPAC synoptic pattern is monsoonal w/ off equatorial heating (from ex-#TD9E, #Hilda, & #91E) driving low-level SW flow. pic.twitter.com/310k8iyWS3

We'll have to see if the @NHC_Atlantic starts advisories on a tropical cyclone re #91E south of Guatemala at 5pm. This system will produce life-threatening flash flooding in Central America and may have to be watched down the line in the Gulf of Mexico. pic.twitter.com/pR186ndcZR

On the ATCF sector file, we have Tropical Depression #02E. This system is off the coast of SW #Mexico and has some good banding on the northern end. Aside from rip current impacts, no direct impacts is expected at this time. #91E #Tropicspic.twitter.com/pZbhD2z65c

Lots of thunderstorm activity associated with Invest #91E as the sun sets. Very high chance of becoming a tropical system during the next 48 hours. pic.twitter.com/8EPt5woUiw

*NEWLY DESIGNATED #91E INVEST 70% CHANCE OF DVLPMNT NEXT 5 DAYS... pic.twitter.com/pBqkqDT4cN