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Andy Taylor and Gary B. Brassington

1. Sea level anomalies and forecast narratives Many activities are organized around expectations of coastal water levels over the next few days, including mitigation of nuisance coastal flooding ( Sweet et al. 2014 ; Hague et al. 2019 ). Still water levels ( Pugh and Woodworth 2014 ) at the coast are not just a matter of tidal patterns and local storms, but can also be influenced by remote forcing via coastally trapped wave (CTW) mechanisms. While CTWs have received much academic attention

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Paul W. Miller, Alan W. Black, Castle A. Williams, and John A. Knox

/coastal wind products (e.g., lake wind advisory, small craft advisory for winds, brisk wind advisory, gale warning, storm warning, hurricane force wind warning) and an additional suite of products tailored for specific circumstances in which wind is one of several criteria (e.g., dust storm warning, blizzard warning, etc.). The issuance criteria for wind advisories and high wind warnings can be achieved by either sustained winds or wind gusts ( Table 1 ). Table 1. Issuance criteria for NWS wind advisories

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Xinhua Liu, Kanghui Zhou, Yu Lan, Xu Mao, and Robert J. Trapp

uncertainty of the ensemble forecast is high, and the accuracy is low. When low-level forcing, low precipitable water (e.g., 15–20 mm), and relatively low convective available potential energy (CAPE; e.g., 200–500 J kg −1 ) are presented, the conceptual model can identify the average thresholds suitable for local prediction conditions (such as the possibility of the lower-level dryness and the strength of the trigger). b. Make up for the deficiencies of the numerical model and other objective methods In

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Xinhua Liu, Kanghui Zhou, Yu Lan, Xu Mao, and Robert J. Trapp

uncertainty of the ensemble forecast is high, and the accuracy is low. When low-level forcing, low precipitable water (e.g., 15–20 mm), and relatively low convective available potential energy (CAPE; e.g., 200–500 J kg −1 ) are presented, the conceptual model can identify the average thresholds suitable for local prediction conditions (such as the possibility of the lower-level dryness and the strength of the trigger). b. Make up for the deficiencies of the numerical model and other objective methods In

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David O. Blanchard

Adams, D. K. , and Comrie A. C. , 1997 : The North American monsoon . Bull. Amer. Meteor. Soc. , 78 , 2197 – 2213 . AWS , 1961 : Use of the skew T –log p diagram in analysis and forecasting . Vol. 1, AWSM 105-124, 144 pp. [Available from U.S. Air Force Air Weather Service, Scott AFB, IL 62225-5008.] AWS , 1979 : Use of the skew T –log p diagram in analysis and forecasting . AWS/TR-79/006 Revised, 157 pp. [Available from U.S. Air Force Air Weather Service, Scott AFB, IL 62225

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John A. Hart and Ariel E. Cohen

of observed lightning may not be the same in another season. Previous research has indeed highlighted the complexities of warm-season convective regimes. For example, Jankov and Gallus (2004) identified challenges in forecasting during weak-forcing-for-ascent convective regimes, which more frequently typify warm-season patterns, from a numerical modeling perspective. These findings highlight previous research that identifies aspects of warm-season severe storms forecasting that could prove to

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Ryan C. Bunker, Ariel E. Cohen, John A. Hart, Alan E. Gerard, Kim E. Klockow-McClain, and David P. Nowicki

moisture. This initial convection was steered northward in concert with the poleward low-level mass flux accompanying the larger-scale cyclone, while experiencing intensification north of the coastal domain (the geographic area encompassing the Coastal_noc regime). In both of these cases, tornadic-storm-favoring thermodynamic and kinematic profiles existed over a broad portion of the Southeast domain (the geographic area encompassing the SE_noc regime). However, forcing for ascent accompanying the

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Clark Evans, Donald F. Van Dyke, and Todd Lericos

forecast. This implies that forecasters preferred ensemble output that helps them to quickly understand the range of solutions that it provides over specific, detailed information illuminating ensemble spread that can become overwhelming or may not have direct applicability to the current forecast. This finding is supported by insight from the Air Force Weather Agency, who noted that matching their ensemble forecast system’s outputs to specific forecast requirements positively influenced forecaster

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Cynthia B. Elsenheimer and Chad M. Gravelle

-tropical environment driven by mesoscale forcing, these convective initiation “failures” in the DCPD RGB could be the result of weak inhibition where early attempts at deep moist convection occur before the sea-breeze circulation develops. The result is numerous scattered showers within weak updrafts that lack the graupel necessary to initiate the noninductive charging process ( Fig. 2a and Bringi et al. 1997 ). While false alarms were not common, their occurrence suggests the need for robust applied

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Michael J. Brennan, Gary M. Lackmann, and Kelly M. Mahoney

similar results in an early numerical model. The diabatically generated anticyclonic PV anomaly that forms above the level of maximum latent heating is consistent with the downstream ridge formation that shortens the half-wavelength of the upper-level trough–ridge couplet (see, e.g., Uccellini 1990 ). Latent heating and the effectively reduced static stability are consistent with both enhanced vertical motion for a given strength of QG forcing for ascent (e.g., Danard 1964 ) as well as improved

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