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Kelsey M. Malloy and Ben P. Kirtman

States dominates in the north-central and Midwest regions ( Dirmeyer and Kinter 2010 ), and the leading cause is the strengthening of the Great Plains low-level jet (LLJ; Arritt et al. 1997 ; Cook et al. 2008 ; Feng et al. 2016 ; Gimeno et al. 2016 ; Nayak and Villarini 2017 ). The Great Plains LLJ has a diurnal cycle caused by thermal gradient reversals over sloping terrain and frictional decoupling amid a rising boundary layer ( Blackadar 1957 ; Fast and McCorcle 1990 ; Holton 1967 ; Jiang

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Brandon P. Bukunt and Gary M. Barnes

( Burpee et al. 1996 ), now by as much as 32% ( Aberson and Franklin 1999 ). For Felicia, we wish to explore if the global positioning system dropwindsondes (GPS sondes) deployed from the G-IV can provide insight into this TC’s rapid filling close to Hawaii. Specifically, we will examine the interaction of the subtropical jet stream (STJ) with the upper-level circulation of the TC. Hawaii is in an enviable location during the hurricane season because the tropical upper-tropospheric trough (TUTT) is

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Pengyuan Li, Gang Fu, Chungu Lu, Dan Fu, and Shuai Wang

. 2006 ; Gao et al. 2007 ), climatology ( S. Zhang et al. 2009 ), and large-scale environmental factors ( Li et al. 2011 ). However, the detailed formation mechanism of fogs over the YS has not been discussed sufficiently, especially for situations in which low-level jets (LLJs) come into play. Fogs over the YS typically form under a stably stratified atmosphere. The vertical mixing process triggered mainly by the turbulence in the stably stratified atmosphere may be the dominant process in the

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Claudia K. Walters and Julie A. Winkler

1. Introduction Low-level wind maxima occur in a wide variety of different settings. On one end of the spectrum, low-level jets are often observed within the planetary boundary layer in the absence of synoptic disturbances. In a classic study, Bonner (1968) showed that, in the central United States, these boundary layer jets typically are most frequent in late summer and early autumn; exhibit strong diurnal oscillations in height, speed, and direction; and are characterized by a streamflow

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Claudia K. Walters

zones, and latitudinal extent of southerly jet events that occurred during the 1991 and 1992 warm seasons. The configuration types included anticyclonically curved low-level wind maxima, bifurcating wind maxima with cyclonically and anticyclonically turning arms, cyclonically curved maxima, and complex types that displayed a closed cyclonic circulation. For several of the types, either a convergence zone or a deformation zone was evident downstream of the isotach maximum. In addition, a southwest

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Veronika Zwatz-Meise and Günter Mahringer

form 16 October 1989) ABSTRACT SATMOD is an interactive method which combines satellite images and several model output parameters.It is used at the Central Institute of Meteorology and Geodynamics in Vienna for satellite-synoptic researchand for operational analysis and forecast services. In this paper, SATMOD is illustrated by focusing on animportant synoptic phenomenon, namely "jet streaks."1. Introduction Cloud configurations in satellite images are a manifestation of

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Dan Bikos, John Weaver, and Brian Motta

recorded in the state. This note examines the utility of Geostationary Operational Environmental Satellite (GOES) imagery in identifying aspects of the synoptic and mesoscale environments not well resolved by numerical models. Water vapor imagery will be shown to reveal an upper-level jet streak that moved into Oklahoma at the time of convective initiation. Jet streaks can be important to severe convective outbreaks. Fawbush et al. (1951) observed that one of the conditions favorable for tornado

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Christoph Gatzen

. The synoptic-scale forcing associated with such intense jet streaks can be quite strong, helping convection to develop. Derechos that occur under those synoptic conditions are called dynamic ( Johns and Hirt 1987 ) or strongly forced derechos ( Evans and Doswell 2001 ). At the 850-hPa level, an air mass characterized by high equivalent potential temperature ( θ e ) up to 340 K was advected from southeastern central Europe into eastern Germany ( Fig. 1b ). In contrast, intense cooling due to cold

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Jeffrey D. Kelley, David M. Schultz, Russ S. Schumacher, and Dale R. Durran

1. Introduction All sectors of extratropical cyclones can be associated with nonconvective high winds (e.g., Parton et al. 2010 ; Knox et al. 2011 ). One of the phenomena responsible for high winds in cyclones is sting jets (e.g., Browning 2004 ; Clark et al. 2005 ; Schultz and Sienkiewicz 2013 ; Schultz and Browning 2017 ; Clark and Gray 2018 ), although other mesoscale phenomena producing high winds include mountain waves and downslope winds (e.g., Brinkmann 1974 ; Lilly 1978

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Stanley L. Barnes and Bradley R. Colman

predicted data initialized24 h before cyclogenesis became apparent, were submitted to the same QG diagnostic algorithms used to analyzeverifying rawinsonde data. Comparisons reveal that the NGM apparently 1 ) transported too much potentialvorticity, westerly momentum, and cold air into the lower troposphere along the axis of the jet stream; 2) movedthe first of two short-wavelength jet streaks too far northeastward and with too much strength; 3) failed topredict the strength of the following jet maximum

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