This is an independent research/prototype tool, not an official source. Warnings, watches, and the official forecast for this storm come from the National Hurricane Center.
Hurricane KarinaEP112026
20.1°N 138.4°W · moving WNW at 8 kt · Advisory 31, 2026-09-04 03:00 UTC
Rapid intensification
- +55 kt/24 h peak — 2026-08-30 00:00 UTC to 2026-08-31 18:00 UTC(60 → 120 kt, +60 kt across the episode)
Based on preliminary operational best-track data. NHC's post-season reanalysis can revise a storm's wind history — in marginal cases, this could change whether the storm still meets the RI threshold.
Intensity — past 72 h and official forecast
Rapid intensification probabilities
SHIPS rapid intensification index (RII): probability of each wind gain over each period, with its multiple of the basin climatological rate. Parsed from the 2026-09-04 06:00 UTC SHIPS run.
RI ingredients
Warm water is the storm’s fuel — RI is rare below about 26.5 °C, and the most explosive cases ride water of 29 °C or more.
Heat content measures how deep the warm water goes — a deep warm layer keeps the storm’s own mixing from stirring up cold water that would cut off its fuel.
Shear tilts and ventilates the developing core — the calmer the winds aloft, the easier it is for the warm core to stack up vertically and deepen.
A moist middle atmosphere protects the core — dry air pulled in from outside evaporates cloud, cools the updrafts, and stalls intensification.
Values from the 2026-09-04 06:00 UTC SHIPS run, along the forecast track. Band edges are approximate guides drawn from rapid-intensification studies, not sharp physical cutoffs — storms occasionally intensify through “unfavorable” environments, and plenty of favorable setups never produce RI. Planned additions: ocean salinity (barrier layers) and inner-core structure.