Hurricane Forecast Model Output, a product of the Tropical Cyclone and Severe Storms Research Group, UW-Milwaukee, Prof. Clark Evans.

Ever wonder which forecast model each of those three or four letter identifiers refers to on the forecast model track and intensity plots? Or what the difference is between various model types? This list, current as of the 2014 hurricane season, has the answers. Click here for the partial source document for this list, or click here for a listing of deprecated identifers (e.g., to help interpret the historical forecasts available from this page).


Official Forecasts

These five identifiers represent forecasts issued by NOAA's National Hurricane Center (NHC), Central Pacific Hurricane Center (CPHC), Weather Prediction Center (formerly Hydrometeorological Prediction Center), and Ocean Prediction Center. While derived from official sources of information, they should NOT be considered to be official.

OFCL Official NHC/CPHC Forecast
OFCI Official NHC/CPHC Forecast Interpolated Ahead 6 hr
OHPC Official Hydrometeorological Prediction Center Forecast
OOPC Official Ocean Prediction Center Forecast

Dynamical Models

These identifiers represent forecasts obtained from weather forecast models that solve mathematical equations that describe how wind, temperature, and moisture evolve within the atmosphere. Most of these models forecast the weather over the entire globe and are not specifically designed for tropical storm and hurricane forecasting.

AVNO / GFSO Global Forecast System Model Forecast
AVNI / GFSI Previous GFS Forecast Interpolated Ahead 6 hr
AP## GFS Ensemble Member Forecast (## = 01 to 20)
AEMN GFS Ensemble Mean Forecast
AEMI Previous AEMN Forecast Interpolated Ahead 6 hr
CMC Canadian Global Model Forecast
CMCI Previous CMC Forecast Interpolated Ahead 6 hr
COTC U.S. Navy COAMPS-TC Model Forecast
COTI U.S. Navy COAMPS-TC Model Forecast Interpolated Ahead 6 hr
COAL U.S. Navy COAMPS-TC Model Forecast, Atlantic Basin
COAI Previous COAMPS-TC Atlantic Forecast Interpolated Ahead 6 hr
COCE U.S. Navy COAMPS-TC Model Forecast, E. Pacific Basin
COEI Previous COAMPS-TC E. Pacific Forecast Interpolated Ahead 6 hr
EGRR / UKX UKMET Model Forecast
EGRI / UKXI Previous UKMET Forecast Interpolated Ahead 6 hr
EMX / ECMF ECMWF Model Forecast (rare)
EMXI Previous ECMWF Forecast Interpolated Ahead 6 hr (rare)
NAM North American Mesoscale Model Forecast
NAMI Previous NAM Forecast Interpolated Ahead 6 hr
NGPS / NGX U.S. Navy NOGAPS Model Forecast
NGPI / NGXI Previous NOGAPS Forecast Interpolated Ahead 6 hr
NVGM U.S. Navy NAVGEM Model Forecast
NVGI Previous NAVGEM Forecast Interpolated Ahead 6 hr

Limited-Area Dynamical Models

These identifiers represent forecasts obtained from weather forecast models that solve mathematical equations that describe how wind, temperature, and moisture evolve within the atmosphere. Unlike the "Dynamical Models" above, however, these models forecast the weather only over a small portion of the globe and are specifically developed to forecast tropical storms and hurricanes.

GFDL GFDL Hurricane Model Forecast Track/Intensity
GFDI Previous GFDL Forecast Interpolated Ahead 6 hr
GHMI Previous Intensity-Modified GFDL Forecast Interpolated Ahead 6 hr
GFDT GFDL Forecast Using a Different Vortex Tracking Algorithm
GFTI Previous GFDT Forecast Interpolated Ahead 6 hr
GFDN Navy-Initialized Version of the GFDL Hurricane Model
GFNI Previous Navy-Initialized GFDL Forecast Interpolated Ahead 6 hr
GFDE Extrapolated GFDL Forecast
HWRF HWRF Hurricane Model Forecast Track/Intensity
HWFI Previous HWRF Forecast Interpolated Ahead 6 hr

Consensus Models

These identifiers represent forecasts obtained from the average, or consensus, of multiple weather forecast model track and/or intensity forecasts. Simple averaging, weighted averaging, and bias-corrected averaging procedures may be used, depending upon the consensus model in question.

IVCN Variable Intensity Consensus of DSHP, LGEM, HWFI, GHMI, and GFNI Models
GUNA Consensus of AVNI, GFDI, EGRI and NGPI Model Track Forecasts
CGUN Bias-Corrected GUNA Forecast
TCON / TCOE Consensus of AVNI, EGRI, NGPI, GHMI, and HWFI Model Track Forecasts
TCOA Consensus of AVNI, EGRI, GHMI, and HWFI Model Track Forecasts
TCCN Bias-Corrected TCON Forecast
TVCN Variable Consensus of AVNI, EGRI, EMXI, NGPI, GHMI, HWFI Model Track Forecasts
TVCE Variable Consensus of AVNI, EGRI, EMXI, NGPI, GHMI, GFNI, HWFI Model Track Forecasts
TVCA Variable Consensus of AVNI, EGRI, EMXI, GHMI, GFNI, HWFI Model Track Forecasts
TVCC Bias-Corrected TVCN Forecast
RYOC / MYOC Forecaster-Generated Consensus Guidance (rare)

Statistical and Statistical-Dynamical Models

These identifiers represent forecasts obtained from weather forecast models that solve statistical equations that describe how a tropical storm or hurricane moves and/or changes intensity in response to climatology and/or present and forecast weather conditions in its proximity. These models are less complex than the "Dynamical Models" and "Limited-Area Dynamical Models" described above; however, many of them are as skillful, if not more skillful, than the more complex models.

A98E NHC-98 Track Model (old, unreliable)
BAMD Deep-Layer Beta and Advection Model Track Forecast
BAMM Medium-Layer Beta and Advection Model Track Forecast
BAMS Shallow-Layer Beta and Advection Model Track Forecast
CLIP 72-hr Climatology and Persistence Track Forecast
CLP5 120-hr Climatology and Persistence Track Forecast
LBAR Limited Area Barotropic Model Track Forecast (old, unreliable)
LGEM Logistical Growth Error Model Intensity Forecast
SHFR 72-hr SHIFOR Model Intensity Forecast
SHF5 120-hr SHIFOR Model Intensity Forecast
DSHF 120-hr Decay SHIFOR Model Intensity Forecast
SHIP SHIPS Model Intensity Forecast
DSHP Decay SHIPS Model Intensity Forecast
DRCL DeMaria Climatology and Persistence Model Intensity Forecast
MRCL McAdie Climatology and Persistence Model Intensity Forecast
RI## Rapid Intensification Aid (## = 25, 30, 35, 40)

Experimental Models (HFIP Stream 1.5)

From time to time, additional models in the Hurricane Forecast Improvement Program, or HFIP, quasi-operational "Stream 1.5" may appear within the guidance products. The identifiers below represent forecasts from models that NHC forecasters are currently evaluating for possible future use in actual NHC forecast operations. The most up-to-date information on these experimental products may always be found at the HFIP Home Page.

FIM9 Finite-Volume Icosahedral Model Forecast
FM9I Previous FIM9 Forecast Interpolated Ahead 6 hr
CTCX Experimental U.S. Navy COAMPS-TC Model Forecast
CXTI Previous Experimental COAMPS-TC Forecast Interpolated Ahead 6 hr
HWFH Experimental NOAA/HRD HWRF Forecast
HWHI Previous Experimental NOAA/HRD HWRF Forecast Interpolated Ahead 6 hr
GP## GFDL Ensemble Member Forecast (## = 00 to 09)
GPMN GFDL Ensemble Mean Forecast
GPMI Previous GFDL Ens. Mean Forecast Interpolated Ahead 6 hr
HHYC HWRF with HYCOM Ocean Model
HHYI Previous HWRF with HYCOM Ocean Model Forecast Interpolated Ahead 6 hr
HW## HWRF Ensemble Member Forecast (## = 00 to 20)
HWMN HWRF Ensemble Mean Forecast
HWMI Previous HWRF Ens. Mean Forecast Interpolated Ahead 6 hr
UWN4 University of Wisconsin NMS Model Forecast
UW4I Previous UW NMS Forecast Interpolated Ahead 6 hr
TV15 Consensus of Available HFIP Stream 1.5 Model Forecasts
MMSE FSU Multimodel Superensemble
SPC3 Statistical Prediction of Intensity Forecast (six members)

Early Versus Late Models

The National Hurricane Center and other official tropical cyclone forecast centers make use of two different forms of dynamical model guidance during the forecast process: "early" and "late" models. Numerical models are typically run four times per day: 0000, 0600, 1200, and 1800 UTC. These times correspond to 8 pm, 2 am, 8 am, and 2 pm EDT, respectively. However, National Hurricane Center official forecasts are issued at 0300, 0900, 1500, and 2100 UTC. These times correspond to 11 pm, 5 am, 11 am, and 5 pm EDT, respectively. Ideally, model forecasts from the 0000 UTC cycle would be available to help make the 0300 UTC forecast (for example); however, as modern numerical weather prediction models typically require several hours to complete a given forecast cycle, this is often not possible.

To alleviate this, model forecasts from the previous cycle, or 1800 UTC in our current example, are shifted forward in time by 6 hr. This results in what is known as an interpolated, or "early", model that is available at 0000 UTC for forecasters to use when preparing the 0300 UTC forecast. The actual 0000 UTC model forecast, arriving after the 0300 UTC forecast must be made, is known as a "late" model forecast. As you might expect, "late" model forecasts thus form the basis for the subsequent "early" model forecasts. In the lists above, "early" models are those whose designators end in an I (e.g., AVNI, CMCI, etc.). "Late" models have no such notation. Please note that all consensus, statistical, and statistical-dynamical guidance is classified as "early" guidance and is often derived from "early" model output.


Disclaimer: The data displayed here are informational only and should NOT be used for making life and death decisions. Always take the word of official sources - the National Hurricane Center and your local National Weather Service office - when preparing for any potential storm impact. If anything on these plots causes confusion, disregard the information in its entirety. The availability, timeliness, and reliability of these data are not guaranteed, and no liability is implied or expressed by your use of this website.


Site and Contents © 2007-2014, Clark Evans (with selected help from Shane Young).