Tropical Weather Watch: Two-C (02C)
# Discussion - - - - - - - - - - - - - - - - - - - - **Last updated:** Friday, August 21 — 8:30 AM
**BLUF:** A newly formed tropical depression situated to the east-southeast of the islands is likely to become Tropical Storm Moke later today. The storm will strengthen as it moves west-northwestward toward the Big Island over the next couple of days but will turn westward later in the weekend and will pass well to the south of the islands. Although direct wind impacts are not expected from this storm, heavy rain and the risk of flash flooding continue to be the primary threat, especially for the Big Island and in areas where the ground is still saturated from Hurricane Lala’s rains.
Satellite imagery analysis indicates that Tropical Depression Two-C is finally getting its act together. Bands of deeper convection are now wrapping into a more defined low-level center, suggesting that this system is on the cusp of strengthening into a tropical storm. Intensity estimates derived from satellite imagery analysis and aircraft reconnaissance data from a recent U.S. Air Force Hurricane Hunters mission indicate that this increased organization has not yet translated to an increase in strength. Maximum sustained winds are holding steady near 35 miles per hour.
Environmental conditions will remain generally favorable for the next 24 to 36 hours, allowing this system to strengthen into a tropical storm later today and continue to intensify as it approaches the Big Island over the weekend. The storm is expected to reach its peak intensity on Saturday evening while still a few hundred miles east-southeast of the Big Island. Stronger shear and decreased mid-level moisture will halt the storm’s intensification and cause it to weaken as it passes to the south of the islands from Sunday through Monday. This system will remain a tropical storm as it passes south of the islands and is expected to weaken into a tropical depression as it exits the region to the west-southwest of the islands on Tuesday.
The depression is moving west-northwestward along the southern periphery of a subtropical ridge positioned to the northeast of the islands. This ridge will build and push westward over the weekend, pushing the storm onto a more westward track which will keep it well to the south of the islands. All islands remain outside the forecast cone of uncertainty and outside the 34-knot sustained wind radius and the forecast track has slowly crept southward away from the islands over the past few advisories. The storm will pass to the south of Kauaʻi during the late evening hours on Monday and will exit the region on Tuesday morning.
# Impacts - - - - - * **Wind impacts:** Direct wind impacts are not expected from this system. However, gusty trade winds are likely to occur as the pressure gradient between strong high pressure to the north of the islands and the storm tightens beginning during the late evening hours on Saturday and continuing through Monday.
* **Rain impacts:** Heavy rain and the risk of flash flooding remain the primary threat from this storm. Shear will be displacing the bulk of the storm’s heaviest rain away from its low-level center and toward the islands from late Saturday into Monday. The Big Island is expected to take the brunt of the rainfall, with 5 to 10 inches of rain expected and isolated maxima of 15 inches in areas of higher terrain. The smaller islands will see less rainfall, with rainfall totals ranging from 1 to 3 inches with isolated maxima of 4 inches in higher terrain, especially on Maui.
* **Marine impacts:** Large swells generated by this storm will reach the islands on Saturday and may cause dangerous surf conditions and rip currents along east-facing shores. These swells will spread westward from the Big Island to the rest of the islands through Monday and dangerous conditions will taper off by Monday night.
# Latest observation - - - - - - - - - - - - - - - - - - - - **Last updated:** Friday, August 21 — 5:00 AM
## Observed information
* **Current position:** 13.4°N 146.0°W * **Forward movement:** WNW (295°) at 10 mph ▼ * **Maximum sustained winds:** 35 mph * **Minimum central pressure:** 1005 millibars ▼
## Relative position
* 743 miles east-southeast of **Hilo** * 746 miles east-southeast of **Ka Lae** * 790 miles east-southeast of **Kailua-Kona**
# Resources - - - - - ## Official information
### Central Pacific Hurricane Center
* [**Homepage**](https://www.nhc.noaa.gov/gtwo.php?basin=cpac&fdays=7)
* [**Public advisory**](https://www.nhc.noaa.gov/text/refresh/MIATCPCP3+shtml/DDHHMM.shtml?)
* [**Forecast discussion**](https://www.nhc.noaa.gov/text/refresh/MIATCDCP3+shtml/DDHHMM.shtml?)
### Forecast graphics
* [**Forecast track and cone**](https://www.nhc.noaa.gov/refresh/graphics_cp3+shtml/DDHHMM.shtml?cone#contents)
* [**Wind speed probabilities**](https://www.nhc.noaa.gov/refresh/graphics_cp3+shtml/DDHHMM.shtml?tswind120#contents)
* [**Arrival time of winds**](https://www.nhc.noaa.gov/refresh/graphics_cp3+shtml/DDHHMM.shtml?mltoa34#contents)
### National Weather Service
* [**WFO Honolulu homepage**](https://www.weather.gov/hfo)
* [**State forecast discussion**](https://www.weather.gov/hfo/AFD)
* [**State marine forecast**](https://www.weather.gov/hfo/marine)
### Hawaii State Civil Defense
* [**Hawaii State Civil Defense**](http://dod.hawaii.gov/hiema/)
* [**Hawaii State Civil Defense Preparation Plan**](http://dod.hawaii.gov/hiema/get-ready/prepare-your-home/)
## Unofficial information
* [**r/TropicalWeather Discussion for Two-C**](https://www.reddit.com/r/TropicalWeather/comments/1vtvfam/02c_central_pacific_eastsoutheast_of_hawai%CA%BBi/)
* [**r/Hawaii Disaster Preparation Wiki**](https://www.reddit.com/r/hawaii/wiki/disaster)