Making the Unpredictable Predictable in Hurricane Forecasts

The chaotic, swirling winds just above the ocean as a hurricane develops play a key role in how strong a storm might be when it reaches land. Helping forecasters better account for this seemingly unpredictable wind turbulence that drives a hurricane's intensity is what scientists with the Northern Gulf Institute and NOAA are doing. Their … Continue reading Making the Unpredictable Predictable in Hurricane Forecasts

Study of how accurate forecast models are in the region close to the ocean surface published in the Journal of Advances in Modeling Earth Systems

Poor modeling of hurricane boundary layer turbulence in computer models is a key obstacle to improving hurricane intensity forecasts. This study uses a recently developed modeling framework based on a large-eddy simulation, or LES, (where model grids are small enough to resolve turbulence) to evaluate the pros and cons of four different planetary boundary layer … Continue reading Study of how accurate forecast models are in the region close to the ocean surface published in the Journal of Advances in Modeling Earth Systems

Study that uses buoy and tower data to improve how models forecast the interaction between the atmosphere and ocean in tropical cyclones published in the Journal of Geophysical Research Oceans

Modeling the interaction between the atmosphere and the ocean is important for accurate forecasting of tropical cyclones, especially their intensities.  Because these interactions are so complex, we typically model these interactions using what we call parameterizations to estimate what is really happening.  One parameter, the drag coefficient, is the resistance between motions in the atmosphere … Continue reading Study that uses buoy and tower data to improve how models forecast the interaction between the atmosphere and ocean in tropical cyclones published in the Journal of Geophysical Research Oceans

Paper investigating the effects of grid resolution, horizontal turbulence models, and horizontal mixing length on real hurricane forecasts published online in the Journal of Advances in Modeling Earth Systems

Physical parameterizations in computer models need to consider the unique structures of tropical cyclones. The study helps us understand turbulent mixing to advance how we account for it in our forecast model parameterizations to improve forecasts. Summary: Tropical cyclones are fueled by the heat from the warm ocean below.  This heat energy moves upward into … Continue reading Paper investigating the effects of grid resolution, horizontal turbulence models, and horizontal mixing length on real hurricane forecasts published online in the Journal of Advances in Modeling Earth Systems

Study on improvements to NOAA’s hurricane forecast model and the way it predicts the region closest to the surface published in Weather and Forecasting

We modified the way NOAA’s new hurricane model forecasts what happens in the lowest part of the atmosphere based on observations from Hurricane Hunter research flights. The new scheme produced track forecasts that were up to 20% better than from the older scheme, a 15% improvement in detection of rapid intensification events, and smaller tropical … Continue reading Study on improvements to NOAA’s hurricane forecast model and the way it predicts the region closest to the surface published in Weather and Forecasting

Study on improving tropical cyclone forecasts by improving the way turbulence near the surface is modeled highlighted in EOS

Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Read the highlight at https://eos.org/editor-highlights/hurricane-forecast-improvement-with-better-turbulent-processes. Read more about this study at https://noaahrd.wordpress.com/2021/09/30/study-on-improving-tropical-cyclone-forecasts-by-improving-the-way-turbulence-near-the-surface-is-modeled-published-in-the-journal-of-geophysical-research/. For more information, contact aoml.communications@noaa.gov.

HRD Monthly Science Meeting of August 2021

August's science meeting consisted of two presentations: Stanley Goldenberg - "NOAA’s August Update of the 2021 Atlantic Hurricane Season Outlook: Methodology & Forecast"  Tomislava Vukicevic - "Sensitivity of microphysics parameterization to stochastically perturbed parameters" Copies of the two presentations are available on the anonymous ftp site at: ftp://ftp.aoml.noaa.gov/pub/hrd/blog/meetings/2021/Science/HRD_SciMeet_20210812.zip

Study on improving tropical cyclone forecasts by improving the way turbulence near the surface is modeled published in the Journal of Geophysical Research

This paper shows that correctly representing the details of processes in model physics schemes can lead to big forecast skill improvement (up to 10 kt).  The large number of cases provide confidence in the results.  Summary: The planetary boundary layer (PBL) is the lowest part of the atmosphere, typically within about 1 km of the Earth’s surface. … Continue reading Study on improving tropical cyclone forecasts by improving the way turbulence near the surface is modeled published in the Journal of Geophysical Research

Study on small-scale vortices near the surface in tropical cyclones published in Scientific Reports

The full paper can be accessed at https://www.nature.com/articles/s41598-021-97766-7.pdf. For more information, contact aoml.communications@noaa.gov.Jie Tang and Xiaotu Lei were supported by the Key Program for International S&T Cooperation Projects of China (No. 2017YFE0107700), National Natural Science Foundation of China (No. 41475060 and 41775065) and the ESCAP/WMO EXOTICCA Project. Jun Zhang was supported by NOAA grant NA19OAR0220186 … Continue reading Study on small-scale vortices near the surface in tropical cyclones published in Scientific Reports

Study showing the impact of turbulence in computer forecasts of hurricanes published in The Journal of the Atmospheric Sciences

Summary:  Turbulence is made up of random and continuously changing wind.  It is important in tropical cyclones because turbulence in the lowest 1-2 km of the atmosphere (the planetary boundary layer or PBL) and in clouds affects tropical cyclone intensity and structural change. Meteorologists use computer models to forecast the weather, including tropical cyclones.  These … Continue reading Study showing the impact of turbulence in computer forecasts of hurricanes published in The Journal of the Atmospheric Sciences