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Wayne F. Feltz and John R. Mecikalski

thunderstorm event is explored. Using part of the array of five AERI instruments stationed across Oklahoma and Kansas as part of the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Program, time series of vertical temperature and water vapor profiles, CAPE, and CIN are analyzed. These datasets provide a unique, real-time assessment of the preconvective atmosphere, not available from conventional sounding observations, which are taken only at 0000 and 1200 UTC synoptic times (or in

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Haidao Lin, Stephen S. Weygandt, Agnes H. N. Lim, Ming Hu, John M. Brown, and Stanley G. Benjamin

1. Introduction The Atmospheric Infrared Sounder (AIRS), launched in May 2002 on the National Aeronautics and Space Administration (NASA) Earth Observing System (EOS) polar-orbiting Aqua platform, is a 3.7–15.4- μ m infrared spectrometer with 2378 spectral channels and 13.5-km horizontal resolution at nadir ( Aumann et al. 2003 ). By measuring radiation in more than 2000 different channels, AIRS provides atmospheric temperature and water vapor information at higher vertical resolution than

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Tom H. Zapotocny, W. Paul Menzel, James P. Nelson III, and James A. Jung

remotely sensed data types studied are SSM/I vertically integrated precipitable water (SSM/I), TOVS temperature profiles down to cloud top (TOVCD), GOES Sounder three-layer clear-air precipitable water (GOESPW), GOES Imager infrared cloud-drift winds (GOESCD), and GOES Imager cloud-top water vapor winds (GOESWV). All five of these data types are used only within a marine environment within the EDAS. The five in situ data types analyzed are rawinsonde temperature and moisture observations (RAOBM

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M. Rouault, S. A. White, C. J. C. Reason, J. R. E. Lutjeharms, and I. Jobard

magnitudes to those above the Gulf Stream and Agulhas Current. Observational evidence for the significant latent heat fluxes in the Agulhas region was obtained during the Agulhas Current Air Sea Exchange Experiment (ACASEX) of autumn 1995, the first dedicated air–sea interaction research cruise in this current ( Rouault et al. 1995 ). Most of the measurements showed that the core of the Agulhas Current, about 80 km wide, transferred about 5 times as much water vapor to the atmosphere as the surrounding

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Kathryn M. Newman, Craig S. Schwartz, Zhiquan Liu, Hui Shao, and Xiang-Yu Huang

on the impacts of a specific instrument, while L12 only examines AMSU-A impacts. L12 specifically notes that future work should examine radiance assimilation from other instruments. This study builds on Schwartz et al. (2012) and L12 by assessing the impacts from assimilating MHS radiances in addition to AMSU-A and conventional observations. Notably, the MHS is designed to retrieve profiles of atmospheric water vapor ( Davis 2007 ; NOAA 2014 ), and atmospheric moisture profiles have been

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A. Tafferner, T. Hauf, C. Leifeld, T. Hafner, H. Leykauf, and U. Voigt

, SYNOPs, and METARs. Also new icing points are introduced if there is a clear indication for icing conditions at the surface or up to a certain height from the surface reports. Furthermore, SYNOP and METAR reports of cloud cover and ceiling are used to examine the diagnosed icing field for cloudless regions, providing a “cloud-corrected icing.” Last, icing intensity is calculated from water vapor saturation mixing ratio at cloud base and mixing ratio within the cloud as forecast by the LM. All of

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Bettina Bauer-Messmer, James A. Smith, Mary Lynn Baeck, and Wenjie Zhao

1. Introduction Many factors that lead to heavy rainfall and associated flash flooding have been identified, for example, ample supply of water vapor and high precipitation efficiency ( Doswell et al. 1996 ). Nevertheless, small differences in the storm environment often can make the crucial difference between a heavy rainfall event and events that pose little danger from flash flooding. Case studies of storms that grow in similar environments but develop different storm characteristics allow

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Hui Li, Panmao Zhai, Yang Chen, and Er Lu

teleconnection cases and persistent precipitation processes in SC will be addressed. The differences from the other four cases will also be briefly discussed. 4. Persistent precipitation processes in South China and the EAP pattern a. Link to wind and water vapor transport at 850 hPa Since the occurrence of persistent precipitation processes is related to the water vapor transport in the lower troposphere, it is necessary to analyze the anomalies of wind speed in the lower troposphere, as well as water vapor

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Shih-Yu Wang and Adam J. Clark

analysis throughout the troposphere. The cross-front circulation is also noticeably stronger in the forecast, with an upright ascending branch immediately north of the surface front where the majority of precipitation occurs. The stronger ascending motion corresponds with the strong lower-level winds converging toward the front, which agrees with the stronger T 3 in the forecast ( Fig. 4i ). In addition, the stronger convergence of momentum enhances the convergence of water vapor flux toward the

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Mark DeMaria, John A. Knaff, and Bernadette H. Connell

that the moistening in the lower to middle troposphere, and the subsequent reduction in entrainment effects, is an important precursor for tropical cyclone formation. Because moisture is a difficult parameter to measure (especially in the region considered in this study, which does not have radiosonde coverage) the aviation analyses were not used for the midlevel moisture variable. Instead, the brightness temperatures from GOES-8 6.7- μ m (also referred to as water vapor or channel 3) imagery

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