Man Zhang1,2,3, Grant Firl3,5, Mrinal Biswas3,5, Dom Heinzeller1,2,3,Ligia Bernardet1,3, Michael Ek3,5, Eric Aligo4, Chunxi Zhang4

1 NOAA/ESRL/Global Systems Laboratory, Boulder, CO2 University of Colorado/CIRES, Boulder, CO3 Developmental Testbed Center, Boulder, CO

4 IMSG, NOAA/NWS/NCEP/EMC, College Park, MD5 National Center for Atmospheric Research, Boulder, CO

Improving Tropical Cyclone Forecasting through Physics Advancement: Using the HWRF Physics Suite in the NOAA’s New Hurricane Analysis and

Forecast System

1st UFS Users’ Workshop, Jul 27-29, 2020

NOAA Hurricane Supplemental Project: *Implement HWRF physics in FV3 via CCPP; Configure, test and validate for HAFSv0.1

Outline

Project overview HWRF physics in HAFS HWRF physics suite test plan Statistical evaluation Hurricane Dorian (2019) Summary

2

Active HAFS developments are ongoing withcollaborative efforts among NCEP/EMC1,AOML/HRD2, GFDL3, ESRL/GSD4, ESRL/NESII5,OFCM/AOC6, and NCAR/DTC7.

A. Mehra et al.Hurricane Analysis and Forecast System (HAFS):

A UFS (Unified Forecast System) ApplicationMonday, 12:05PM, Introductory Session

3

Scheme/Suite HWRF HAFS_p0.1

Microphysics Ferrier-Aligo with separate cloud species advection

GFDL

PBL K-EDMFw/ HWRF namelist settings

K-EDMFw/ HWRF namelist settings

Deep/shallow CU saSAS with HWRF settings on in all domains

saSAS with GFS settings on in all domains

Radiation HWRF-RRTMG GFS-RRTMG

Surface layer GFDL GFSw/ HWRF namelist settings

LSM HWRF-Noah GFS-Noah

Orographic GWD on for 13km; off for 3 km on for 13km; off for 3 km

Non-stationary GWD off off

Ozone NRL_2015 NRL_2015

H2O NRL_2015 NRL_2015

Overview of HWRF Suite in CCPP

D. Heinzeller et al.The Common Community Physics Package (CCPP):

a shared infrastructure for model physics for operations and research

Monday, 3:15PM Plenary Session

• HAFS_p0.1: UFS MWR physics suitewith Hurricane specific modifications

• The implementation of HWRF physicsinto UFS via CCPP is a collaborative effortbetween DTC, NOAA/GSL andNOAA/EMC. HWRF physics suite isavailable in hafs-community/HAFSrepository

Yellow highlights indicate aspects that differ between the suites.

HWRF Physics Suite Test Plan

4

Storms First cycle Last cycle

05L Dorian 2019082406 2019090718

09L Humberto 2019091212 2019091906

13L Lorenzo 2019092212 2019100206

2019 AL Priority Storms

• All experiments were conducted on the Mississippi State University Orion High-Performance Computing system

• The results were compared against the EMC 2019 real-time HAFS runs (HSAR)• Neither vortex initialization nor data assimilation was employed

HAFS v0.a/v0.b Experiments with ATCF identifier

HAFS v0.a (LAM)

HAFS v0.b (global-nesting)

HAFS C768 with refinement ratio of 4

Courtesy of A. Mehra (NOAA/EMC)

Overall Performance Assessment+

5

HWRF HAFS_p0.1

SAR(v0.a) HAHW HAH1

NEST(v0.b) HBHW HBH1

+ Model Evaluation Tools –Tropical Cyclone*HSAR is the 2019 HAFS EMC real-time (Dong et al. 2020) results

HAHW HAH1

f72 Hourly Max 10-m Wind Speed (kt)

Excessive storm size in HWRF physics suite!!

Dorian (2019)IC:20190901 18UTC

6

HAH1 f72

HAHW f72

HAH1 f72

HAHW f72

• In HAFS_p0.1 suite, GFS saSAS scheme (i.e. convective

precip) takes control of the rainbands

• In HWRF suite, FA mp takes control of the whole storm,

including the eyewall and rainbands

Dorian 6-h Total Precipitation (mm) and EP Fraction

*HAH1 uses GFS saSAS schemes; HAHW uses HWRF saSAS schemes

EP dominates

CP dominates

Dorian (2019)IC:20190901 18UTC

Summary HWRF physics suite is available in the feature branch of hafs-

community/HAFS repository Results of the first exercise with HWRF physics in HAFS are

promising: Better mean track forecast than HAFS_p0.1 suite, especially cross

track error in both regional and global-nesting configuration Improved intensity forecasts compared to HAFS_p0.1 and HSAR Excessive size of the storms Stronger storm-scale precipitation structure in rainbands

Additional customization and testing in a larger and morediverse sample size is needed to realize the benefits of thissuite

7

Humberto (09L2019)

HWRF suite less likely to make false landfall forecasts

HAH1 HBH1

HAHW HBHW

Dorian (05L2019)

8

GFS

HWRF

HMON

HAH1

2019 EMC HAFS-SAR Real-time EXP

2020 DTC HWRF Physics Test

HAHW

HBH1

HBHW

HSAR

J. Dong et al.The Hurricane Analysis and Forecast System (HAFS)-Stand-Along Regional model (SAR) real-time experiments for the

2019 North Atlantic hurricane season and future developments

Tue, 2:30PM

HWRF HAFS_p0.1

SAR(v0.a) HAHW HAH1

NEST(v0.b) HBHW HBH1