Good day everyone!
Shower and thunderstorm activity still persists around the Yucatan Peninsula in association with a Tropical Wave. The center or axis of this feature is hard to discern on satellite loop imagery, however may be located just west of the thunderstorm activity over the eastern Yucatan Peninsula.
The current and forecast steering layers maps indicate this feature is moving toward the west, and I expect this motion to continue for the next 72 hours. As this enters fully into the BOC, I will be monitoring it closely for development, as upper level winds are forecast to become more conducive for development in about 24 hours.
Satellite loop imagery this morning indicates Tropical Disturbance INVEST 97L continues to become better organized, with heavy convection pretty much over the center. The NHC has increased the probability of 97L becoming a Tropical Cyclone during the next 48 hours to MEDIUM (40%), and to HIGH (60%) over the next 5 days.
Based on the 12Z ATCF FTP data update, the following information was provided on INVEST 97L:
The disturbance is still moving very slowly, and taking on more of a WNW track. Based on forecast steering maps from yesterday, it was indicated 97L would have moved west further before being tugged northward. The Dynamic Model guidance had in fact been showing this turn, with the exception of one run, where they had shifted west. Upon analysis this morning of the current and forecast steering layers maps, and analysis of various satellite channels loop imagery, I found the glitch in my thinking on previous forecast track. The current steering layers map, and satellite loop imagery, indicates a stronger and larger ridge moving in from the west, thereby allowing the trof to nudge further south, and become a little stronger than forecast in the forecast steering maps. So pretty much, the steering layer forecast maps have initialized a weaker scenario in regard to the U.S. ridge, and the east coast trof, as well as a larger break noted in between the two ridges. This is allowing for the current motion of 97L.
Based on re-analysis of these factors, combined with placing the forecast steering in motion, I have to concur with the 12Z Dynamic Model Guidance TVCC / TVCN tracks, until such a time we see how 97L interacts with the area to its NE.
Upper level winds are conducive for further development with an upper level anticyclone established above 97L. Based on the GFS wind shear forecast, upper level winds are forecast to remain favorable during the next 42-48 hours in the forecast track, becoming marginal once 97L moves north of the islands. As 97L begins to move more toward the NNE and NE, upper level winds are forecast to become a little more conducive.
Based on these parameters, save land interaction with Puerto Rico, 97L should continue to organize slowly today, and based on satellite imagery, could be close to depression status.
I will be monitoring this disturbance closely for any significant changes to upper level winds and future steering.
I am also interested in the area to the NE of 97L, as convective activity has increased and become consolidated. I will be monitoring this closely for any significant changes.
Elsewhere, I will be monitoring a Tropical Wave approaching 30W Longitude over the next 72-96 hours for any signs of development. Upper level winds do not currently support development, however based on possible track by forecast steering, upper level winds will become conducive within 72 hours.
Have a blessed day!
T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST
MEMBER WEST CENTRAL FL AMS
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced)