Predictability of mid-summer Great Plains low-level jet and associated precipitation

Details

• Journal Title:
  Weather and Forecasting
• Personal Author:
  Malloy, Kelsey M. ; Kirtman, Ben P.
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; CPO (Climate Program Office) ; WPO (Weather Program Office) ; CIMAS (Cooperative Institute for Marine and Atmospheric Studies)
• Description:
  Warm-season precipitation in the U.S. Corn Belt," the Great Plains, and the Midwest greatly influences agricultural production and is subject to high interannual and intraseasonal variability. Unfortunately, current seasonal and subseasonal forecasts for summer precipitation have relatively low skill. Therefore, there are ongoing efforts to understand hydroclimate variability targeted at improving predictions, particularly through its primary transporter of moisture: the Great Plains low-level jet (LLJ). This study uses the Community Climate System Model, version 4 (CCSM4), July forecasts, made as part of the North American Multi-Model Ensemble (NMME), to assess skill in reproducing the monthly Great Plains LLJ and associated precipitation. Generally, the CCSM4 forecasts capture the climatological jet but have problems representing the observed variability beyond two weeks. In addition, there are predictors associated with the large-scale variability identified through linear regression analysis, shifts in kernel density estimators, and case study analysis that suggest potential for improving confidence in forecasts. In this study, a strengthened Caribbean LLJ, negative Pacific-North American (PNA) teleconnection, El Nino, and a negative Atlantic multidecadal oscillation each have a relatively strong and consistent relationship with a strengthened Great Plains LLJ. The circulation predictors, the Caribbean LLJ and PNA, present the greatest "forecast of opportunity" for considering and assigning confidence in monthly forecasts."
• Source:
  Weather and Forecasting, 35(1), 215-235. https://journals.ametsoc.org/view/journals/wefo/35/1/waf-d-19-0103.1.xml
• DOI:
  https://doi.org/10.1175/WAF-D-19-0103.1.35.1.test
• Document Type:
  Journal Article
• Funding:
  Grant no. NA18OAR4310293 ; Grant no. NA16OAR4310149 ; Grant no. NA16OAR4310141 ; Grant no. NA15OAR4320064
• Place as Subject:
  Central united-states ; us midwest
• Rights Information:
  CC BY
• Compliance:
  Submitted
• Download URL:
  https://repository.library.noaa.gov/view/noaa/28740/noaa_28740_DS1.pdf
• File Type:
  [PDF - 5.68 MB]
• Collection(s):
  Office of Oceanic and Atmospheric Research (OAR) ; NOAA Cooperative Institutes
• Main Document Checksum:
  urn:sha256:c962116181389a1a8960e5d2fef69638cad630063c9fb7c88a6da03bd9eeb3b2