# Presentation: 763224

## National Center for Environmental Prediction (NCEP) Weather Products for Energy

**National Center for Environmental Prediction (NCEP) Weather Products for Energy**

- Jeff McQueen, Jun Du, B. Zhou,
- G. Manikin E. Rogers and Geoff Dimego

## NWS/NCEP Forecast models

**North American Eta 12 km 84 h Forecasts**
***Improved ***_***Physics***_
_**High Resolution**_** Window Non-hydrostatic Mesoscale Model (NMM) :**
** ****8 km, 60 h Forecasts once/day (East: 18z)**
** **** ****26 Fire weather nested grids**
**Short Range **_**Ensemble**_** Forecast System (SREF)**
**Improved **_**assimilation**_** of surface data**
**Medium Range Ensemble Forecasts (15 day)*****	******	******	***

## Eta-12 & NMM Domains

##  NMM Fire Wx real-time selectable domains

** ****4 or 8 km resolution**
** ****8 km: 4x/day or**
** ****4 domains 1x/day**
** ****4 km: Homeland security on demand**

## Eta-12 FY03 : Improved Temperature Forecasts

***Eta-12 FY03 : ******Improved Temperature Forecasts***

_**July 2003 Implementation**_
**Improved cloud radiation assimilation & interactions**
**Decreased warm bias from 2002**
**Strongest improvement over South**
**More sophisticated radiation scheme being developed**
**Incremental improvements**

**EtaX-new minus Eta-Ctl**

## Eta-12 FY03 : Improved Temperature Forecasts

***Largest impact in Southern U.S. And Plains***

##  NMM- 8 km

**8-km resolution over sub-regions of Eta domain**
**Hybrid sigma-pressure coordinate (transition from sigma to pressure at ~400 hPa), with 60 layers total**
**Modified Betts-Miller-Janjic convective scheme**
**NOAH 2.2 land surface package developed at NCEP**
***	******	******	******NOTE:  Will become part of a WRF-NMM ensemble in FY04***

##  2-m Wind Improvement from West Coast

- Wind barbs (kts) and topography (shaded as per color bar)

## Energy Short Range Ensemble Forecast (SREF) System

**Energy Short Range**** Ensemble Forecast (SREF) System**

** ****Breeding: ****5 Eta, 5 Eta-Kain Fritsch, 5 RSM**
** ****Same configuration as operational 48 km SREF except higher resolution --- 32 km**
** ****Physics: ****15 members, 8 from Breeding run**
**cloud physics diversity**
** ****22-members total:  ****15 Eta, 7 RSM**
** ****Both breeding/initial condition and physics perturbations****	**** **
** **

## Energy Short Range Ensemble Forecast (SREF) System

**Domain and resolution**
***Domain is full North American continent***
***Resolution is 32 km / 60 levels***
***Forecast range is 63 hours at 6 and 18 Z***
***Lateral boundary conditions from 6-hr old medium range ensemble system***
**Bias correction of temperatures based on all 22 members**

## SREF Probabilistic  

**SREF Probabilistic  **
**Cloud Cover**

**http://wwwt.emc.ncep****.noaa.gov/mmb/SREF/SREF.html**

## Ensemble Meteogram

***Ensemble Meteogram***

##  Improvements with SREF Forecasts Improved confidence and uncertainty information

**Temperature/wind**
***Terrain effects on wind (Sea/lake breeze, mountain effects) somewhat better resolved***
**Precipitation**
***Precipitation patterns from different convective schemes will differ, especially with weak dynamical forcing***
***Topographic effects better resolved***
***Sharper precipitation features ***

## Slide 14

## Challenges Posed by Ensembles

**Accelerated expansion of NWS ****	*****telecommunications***** infrastructure.**
**Accelerated *****training***** of NWS forecasters.**
**Development of *****ensembling approaches***** and ****	*****display tools*****.**
**Delay of the march toward finer grid resolution until *****computer resources***** grow (could be a positive factor).**

## Developing New Tools

**Advanced SREF Visualizations **
***Used NCEP’s 48-km SREF ensemble to calculate ******probability of occurrence****** for key Severe Wx parameters:***
**Wind Shear > 40 kts in column**
**CAPE > 1000 Joules/kg **
**Convective rain > 0.01 inch**
***Multiply probabilities to form a****** combination probability product:***

##    SREF Wind Shear  Prob>40 kt

***   ******SREF Wind Shear  Prob>40 kt***

##    SREF CAPE > 1000

***   ******SREF CAPE > 1000***

##    SREF Convect. Precip Prob.

***   ******SREF Convect. Precip Prob.***

##    Combined Svr wx probability

***   ******Combined Svr wx probability***

## Advanced SREF Uses

**The “combination” concept can be extended  to provide probablistic guidance identifying *****regions of high risk***** for a variety of weather:**
***Tornados, hail and severe gusts***
***Extreme heat waves, cold snaps***
***Heavy precipitation and flash flooding***
***Ice Storms***
***Gale force winds***
***Frost/freeze warnings***

##  Eta-12 Current Sfc  Assimilation

*** ******Eta-12 Current Sfc  Assimilation***

## Eta-12 Improved Sfc Assimilation COOP sites

***Eta-12 Improved Sfc Assimilation ******COOP sites***

##  Impact of COOP & mesonet data on models

**Improved analysis and short-term prediction of temperature and moisture**
**Improved evaluation of model physics.**

## Summary

**High Resolution Deterministic models**
***Eta-12,  NMM-8, Improved physics***
***Improvements in cloud radiation reduced biases***
**Increased emphasis on ensemble prediction**
***Impact of  higher resolution: SREF-32 km***
***Impact of increased diversity: ***
**From cloud physics perturbations (SREF-32 II)**
**Ensemble mean usually results in best forecast**
**Improved assimilation of surface mesonets**