Storm-Scale Ensemble Forecast for the NOAA HWT Spring ... · For HMT, the following settings are...

ETS in Neighborhood context

PQPF Verification

Localized Probability Match (LPM)

LPM vs PM

West Virginia Flash Floods

In 2016 and 2017, CAPS continued to play

major role in the NOAA Hazardous Weather

Testbed (HWT) Spring Forecast Experiment,

and expanded into contributing to the HMT

Flash Flood and Intensive Rainfall (FFaIR)

Experiment by producing convection-allowing

storm-scale ensemble forecasts (SSEF) over

the entire CONUS domain at 3-km grid

spacing. A FV3 forecast was added in 2017.

The CAPS SSEF is a large part of a

Community Leveraged Unified Ensemble

(CLUE) “grant ensemble” for the HWT

SFE2016 and SFE2017, coordinated among

various groups including NSSL, SPC, CAPS,

NCAR, UND, EMC, GSD, and DTC, in an

effort to provide guidance to the design of

near-future operational SSEF systems for

EMC.

The NSSL Multi-Radar/Multi-Sensor (MRMS)

QPE (Zhang et al. 2011) data were used as

verification dataset for the SSEF QPF.

This work is primarily funded by the NOAA CSTAR

program, HWT and HMT grants.

2017 CAPS SSEF Highlight

• 3-km horizontal grid spacing

(1620×1120)

• WRF version 3.8.1 (coupled with ARPS v5.4)

• HWT: A 3DVAR-based SSEF with 23 ARW members, initiated with 3DVAR radar analysis at 0000 UTC, running on Lonestar5 at TACC; 1 FV3 member

• HWT: A GSI+EnKF-based ensemble forecast with 10-member ensemble forecast starting at 0000 UTC. Running on Bridges at PSC

• HMT: A 3DVAR-based SSEF with 10 ARW members, running on Stampede2; plus a FV3 member, running on OSCER’s Schooner

Storm-Scale Ensemble Forecast for the NOAA HWT Spring Forecasting Experiment and HMT FFaIR Experiment

Fanyou Kong1, Ming Xue1,2, Youngsun Jung1, Keith Brewster1, Nathan Snook1 1Center for Analysis and Prediction of Storms and 2School of Meteorology, the University of Oklahoma, Norman, OK 73072

Forecast domain for the 2017 HWT

SFE and HMT FFaIR (thick inner box

is the verification sub-domain) .

CONUS domain (1620x1120, at 3-km)

For HMT, the following settings are used based on

preliminary experiments:

– Local patch size: 5 × 5 grid points

– Calculation area size: 65 x 65 grid points

– Gaussian smoother standard dev.: 1 grid point

ETS of 3-h accumulated precipitation >=

0.01 inch (top) and 0.5 inch (bottom)

averaged over all 2017 3DVAR SSEF

forecasts initiated at 0000 UTC.

ETS of 3-h accumulated precipitation >=

0.5 inch, averaged over all 2017 3DVAR

SSEF forecasts initiated at 0000 UTC, with

R=8 referring to a neighborhood scale in

grid points.

AUROCs for the

ensemble probability

of 3-h accumulated

precipitation≥0.25,

0.5, and 1.0 inch with

r=8 (~25km).

AUROCs for the

ensemble probability

of 3-h accumulated

precipitation≥0.25,

0.5, and 1.0 inch with

r=0.

Contact Email: fkong@ou.edu

ETS of 3-h accumulated precipitation ≥0.01

(left), and ≥0.5 inch (right), with different

neighborhood scale values.