Invest 99L (AL99) — Latest NHC Outlook (8:00 AM EDT Wed Aug 20, 2025)
- Advisory context: NHC Tropical Weather Outlook (Atlantic)
- Disturbance: Invest 99L (Eastern Tropical Atlantic)
- Status: Tropical disturbance (not yet a tropical depression)
- Formation chances: 30% (48 hours) • 30% (7 days)
- Location/region: Just southwest of the Cabo Verde Islands
- Movement: West at about 15 mph
- Source: NHC Tropical Weather Outlook
What’s happening now
An area of disturbed weather associated with a tropical wave (Invest 99L) is located just southwest of the Cabo Verde Islands. The system is producing showers and thunderstorms, and environmental conditions appear marginally favorable for brief development during the next day or two as it moves westward at about 15 mph. A short‑lived tropical depression could form before conditions become unfavorable for further development late this week.
Key takeaways
- Invest 99L has a 30% chance of formation in 48 hours and 30% through 7 days.
- Location is just SW of the Cabo Verde Islands, moving west around 15 mph.
- Any development window appears short before conditions turn less favorable late week.
- No watches or warnings are in effect; interests in the eastern tropical Atlantic should monitor updates.
Current status (as of 8:00 AM EDT • Aug 20, 2025)
- Disturbance: Invest 99L (AL992025)
- Region: Eastern Tropical Atlantic (just SW of Cabo Verde Islands)
- Movement: W ~15 mph
- Formation chances: 30% (48 hours) • 30% (7 days)
- Structure: Disorganized convection with a tropical wave (per NHC TWO)
Watches and warnings
None.
Forecast overview
- Track: Westward across the eastern tropical Atlantic; monitor for any organization near/just SW of the Cabo Verde Islands.
- Intensity: Brief development possible in the next day or two; conditions become unfavorable late week, which could limit or halt development.
- Confidence: Outlook‑level guidance only; uncertainty remains high until a defined center forms.
Expected impacts
- Marine/Coastal: Gusty squalls and locally heavy showers possible near/just west of the Cabo Verde Islands. No U.S. impacts indicated by NHC at this time.
- Always follow guidance from your national meteorological service.
Maps and official resources
- NHC Tropical Weather Outlook (text): https://www.nhc.noaa.gov/text/MIATWOAT.shtml
- NHC Graphical TWO — 2‑Day: https://www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=2
- NHC Graphical TWO — 7‑Day: https://www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=7
- Satellite imagery (Atlantic): https://www.nhc.noaa.gov/satellite.php
Graphics
Latest NHC Graphical Outlooks (auto‑updating):
Update — 8:00 AM EDT TWO Highlight (Invest 99L)
- NHC TWO notes Invest 99L (Eastern Tropical Atlantic) is a tropical wave just southwest of the Cabo Verde Islands moving west at about 15 mph. A short‑lived tropical depression could form during the next day or two before conditions become unfavorable later this week. Formation chance through 48 hours: 30%. Through 7 days: 30%. Source: https://www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=2
Next updates
- The NHC Outlook typically updates around 2 AM, 8 AM, 2 PM, and 8 PM EDT. This post will be updated as NHC issues new outlooks or if advisories begin on a designated system.
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Source: National Hurricane Center (NHC) Tropical Weather Outlook. U.S. Government publications are in the public domain. Always consult your local meteorological service for location‑specific warnings and preparedness guidance.