Tag: extratropical_transition

2019 Atlantic Hurricane Forecasts from the Global-Nested Hurricane Analysis and Forecast System: Composite Statistics and Key Events

Hazelton, A., Zhang, Z., Liu, B., Dong, J., Alaka, G., Wang, W., … & Marks, F. (2021). 2019 Atlantic hurricane forecasts from the global-nested hurricane analysis and forecast system: Composite statistics and key events. Weather and Forecasting36(2), 519-538.

Abstract: NOAA’s Hurricane Analysis and Forecast System (HAFS) is an evolving FV3-based hurricane modeling system that is expected to replace the operational hurricane models at the National Weather Service. Supported by the Hurricane Forecast Improvement Program (HFIP), global-nested and regional versions of HAFS were run in real time in 2019 to create the first baseline for the HAFS advancement. In this study, forecasts from the global-nested configuration of HAFS (HAFS-global nest) are evaluated and compared with other operational and experimental models. The forecasts by HAFS-global nest covered the period from July through October during the 2019 hurricane season. Tropical cyclone (TC) track, intensity, and structure forecast verifications are examined…

Download Full Paper

Read Full Article

The Extratropical Transition of Tropical Cyclones. Part I: Cyclone Evolution and Direct Impacts

Evans, C., K.M. Wood, S.D. Aberson, H.M. Archambault, S.M. Milrad, L.F. Bosart, K.L. Corbosiero, C.A. Davis, J.R. Dias Pinto, J. Doyle, C. Fogarty, T.J. Galarneau, C.M. Grams, K.S. Griffin, J. Gyakum, R.E. Hart, N. Kitabatake, H.S. Lentink, R. McTaggart-Cowan, W. Perrie, J.F. Quinting, C.A. Reynolds, M. Riemer, E.A. Ritchie, Y. Sun, and F. Zhang, 2017: The Extratropical Transition of Tropical Cyclones. Part I: Cyclone Evolution and Direct Impacts. Mon. Wea. Rev., 145, 4317–4344, https://doi.org/10.1175/MWR-D-17-0027.1

Abstract: Extratropical transition (ET) is the process by which a tropical cyclone, upon encountering a baroclinic environment and reduced sea surface temperature at higher latitudes, transforms into an extratropical cyclone. This process is influenced by, and influences, phenomena from the tropics to the midlatitudes and from the meso- to the planetary scales to extents that vary between individual events. Motivated in part by recent high-impact and/or extensively observed events such as North Atlantic Hurricane Sandy in 2012 and western North Pacific Typhoon Sinlaku in 2008, this review details advances in understanding and predicting ET since the publication of an earlier review in 2003. Methods for diagnosing ET…

Read Full Paper

Read Full Article