Learning Month, Australia – A tropical low, designated 11S (Tropical Low 10U), is currently 1287 kilometers north-northwest of Learning Month, Australia, and has been moving southeastward at 24 km/h (13 knots) over the last six hours, with significant wave heights reaching 4.6 meters (15 feet). This system is expected to undergo changes in both track and intensity over the coming days.
Shifting Winds: What’s Next for Tropical Low 11S?
Forecasters predict a westward turn for the system as steering patterns evolve, with initial intensification followed by weakening.
- Tropical Low 11S is currently tracking southeastward but will likely turn westward within 36 hours.
- The system is expected to intensify initially due to low wind shear, but increasing shear and dry air will lead to weakening.
- Models generally agree on the forecast track and intensity changes, with moderate confidence.
- The system is forecast to weaken below 65 km/h (35 knots) in approximately three days.
Over the next 36 hours, 11S is forecast to continue its southeastward path, influenced by the eastern edge of a low to mid-level near-equatorial ridge. However, a significant shift is anticipated around the 36-hour mark. The steering mechanism will transition to a large subtropical ridge located to the south, causing the tropical low to make a sharp turn westward.
What factors will influence the intensity of this tropical low? The system is forecast to intensify over the next 36 hours as wind shear remains relatively low. However, this intensification is expected to be short-lived. Around 36 hours from now, northwesterly shear is predicted to increase to over 35 km/h (20 knots), initiating a weakening trend as the system begins its westward turn. The influx of dry air, a process known as entrainment, from the west is also expected to contribute to the weakening of the vortex.
Looking ahead, 11S is projected to weaken below 65 km/h (35 knots) in roughly three days as it continues its westward trajectory. Current model guidance demonstrates moderate agreement throughout the forecast period, with no major discrepancies. The GFS model is consistently the fastest in predicting the system’s movement after the westward turn, while the NAVGEM model is the slowest.
The Joint Typhoon Warning Center (JTWC) track forecast aligns closely with the multi-model consensus for the next two days, and then shifts to be more in line with the Google DeepMind ensemble mean. Intensity forecasts generally concur on intensification between 24 and 36 hours, followed by a period of steady weakening. The JTWC intensity forecast also remains consistent with the overall consensus, with a medium level of confidence.
Cross-track spread at 3 days is around 176 km, while along-track spread is 352 km, indicating a degree of uncertainty in the precise path of the system.
The interplay of these atmospheric forces—shifting ridges, wind shear, and dry air intrusion—will ultimately determine the fate of Tropical Low 11S as it moves across the region.
