Understanding Biases in Tropical Cyclone Intensity Forecast Error

Relating Tropical Cyclone Track Forecast Error Distributions with Measurements of Forecast

JMA’s Five-day Tropical Cyclone Track Forecast

Since 22 April 2009, the Japan Meteorological Agency (JMA) has issued five-day tropical cyclone (TC) track forecasts. This paper introduces these forecasts, including the method used, interpretation of the results obtained, forecast cases and future challenges. One of the forecast’s unique aspects is its determination of the radius of a 70% probability circle (PC) using the level of forecast un...

Human influence on tropical cyclone intensity.

Recent assessments agree that tropical cyclone intensity should increase as the climate warms. Less agreement exists on the detection of recent historical trends in tropical cyclone intensity. We interpret future and recent historical trends by using the theory of potential intensity, which predicts the maximum intensity achievable by a tropical cyclone in a given local environment. Although gr...

The Dvorak Tropical Cyclone Intensity Estimation Technique

T HE DVORAK TECHNIQUE LEGACY. The Dvorak tropical cyclone (TC) intensity estimation technique has been the primary method of monitoring tropical systems for more than three decades. The technique has likely saved tens of thousands of lives in regions where over one billion people are directly affected by TCs (commonly called hurricanes, typhoons, or cyclones). The Dvorak technique’s practical a...

Midlevel Ventilation's Constraint on Tropical Cyclone Intensity

Midlevel ventilation, or the flux of low-entropy air into the inner core of a tropical cyclone (TC), is a hypothesized mechanism by which environmental vertical wind shear can constrain a tropical cyclone’s intensity. An idealized framework based on steadiness, axisymmetry, and slantwise neutrality is developed to assess how ventilation affects tropical cyclone intensity via two possible pathwa...