Campus Units

Geological and Atmospheric Sciences, Environmental Science, Human Computer Interaction

Document Type

Article

Publication Version

Published Version

Publication Date

4-1-2020

Journal or Book Title

Weather and Forecasting

Volume

35

Issue

2

First Page

325

Last Page

346

DOI

10.1175/WAF-D-19-0016.1

Abstract

While the implementation of convection-allowing models has improved the representation of convective features, a consensus is lacking regarding what horizontal grid spacing most appropriately resolves convective structures, is computationally feasible, and provides the most useful output to forecasters. The present study evaluates 14 simulated MCSs with 3-, 1- and 0.333-km horizontal grid spacing in order to understand sensitivity in simulated MCS forward propagation speeds and cold pool behavior with decreased grid spacing. MCS cold pools were found to be significantly larger in runs using finer grid spacing. In addition, a greater similarity in solutions occurred when grid spacing was refined to 1 km and less, with 1- and 0.333-km MCS cold pools more similar in magnitude, depth, length, and areal coverage, than 3-km cold pools. The 1-km simulations demonstrated a small increase in forecast skill for 3-h QPF throughout MCS evolution compared to 3-km runs. The 1-km MCS 9-h precipitation swaths were also better aligned with observations compared to 3-km simulations. When evaluating MCS forward propagation speeds, however, 3-km simulated MCS speeds were more similar to observations compared to 1 km.

Comments

This article is published as Squitieri, Brian J., and William A. Gallus Jr. "On the forecast sensitivity of MCS cold pools and related features to horizontal grid spacing in convection-allowing WRF simulations." Weather and Forecasting 35, no. 2 (2020): 325-346. DOI: 10.1175/WAF-D-19-0016.1. Posted with permission.

Rights

Copyright 2020 AMS https://www.ametsoc.org/ams/index.cfm/publications/authors/journal-and-bams-authors/author-resources/copyright-information/copyright-policy/

Copyright Owner

American Meteorological Society

Language

en

File Format

application/pdf

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