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 2022 hurricane season, has the answers. The NHC has an excellent website with more details on the formulations for many of the models listed below. 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).

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Early vs. Late Models

The NHC and other official tropical cyclone forecast centers use two different forms of dynamical model guidance during the forecast process: "early" and "late" models. Dynamical models are typically run four times per day: 0000, 0600, 1200, and 1800 UTC. These times correspond to 8p, 2a, 8a, and 2p EDT, respectively. However, the output from these forecasts is typically not available to NHC forecasters when preparing the corresponding official forecasts that are issued at 0300, 0900, 1500, and 2100 UTC.

Consequently, "early" models represent forecasts from the previous cycle - that beginning 9 hr prior to an official forecast - that are shifted forward in time by 6 hr with a position and intensity matching the storm's current attributes. For dynamical models, these models have designators that end in an I (e.g., AVNI, CMCI, etc.) to indicate their interpolated nature. Note that consensus, statistical, and statistical-dynamical guidance is also classified as "early" guidance since each are derived using "early" model inputs. Conversely, "late" models represent forecasts from the current forecast cycle that arrive late, or after the official forecast must be made. They form the basis for the next forecast cycle's "early" model forecasts. They have no special designator notation.

Official Forecasts

These identifiers represent forecasts issued by NOAA's National Hurricane Center (NHC), Central Pacific Hurricane Center (CPHC), Weather 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 Weather 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. Many of these models forecast the weather over the entire globe, and only some are 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)
AC00	GFS Ensemble Control Forecast
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
CP##	Canadian Ensemble Member Forecast (## = 01 to 20)
CC00	Canadian Ensemble Control Forecast
CEMN	Canadian Ensemble Mean Forecast
CEMI	Previous CEMN Forecast Interpolated Ahead 6 hr
COTC	U.S. Navy COAMPS-TC Model Forecast
COTI	Previous COTC Forecast Interpolated Ahead 6 hr
COAL	U.S. Navy COAMPS-TC Model Forecast, Atlantic Basin
COAI	Previous COAL Forecast Interpolated Ahead 6 hr
COCE	U.S. Navy COAMPS-TC Model Forecast, E. Pacific Basin
COEI	Previous COCE Forecast Interpolated Ahead 6 hr
CTCX	Experimental U.S. Navy COAMPS-TC Model Forecast
CTCI	Previous CTCX 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; generally archives only)
EMXI	Previous ECMWF Forecast Interpolated Ahead 6 hr (rare; generally archives only)
HMON	Hurricanes in a Multiscale Ocean-Coupled Non-Hydrostatic (HMON) Model Forecast Track/Intensity
HMNI	Previous HMON Forecast Interpolated Ahead 6 hr
HWRF	HWRF Hurricane Model Forecast Track/Intensity
HWFI	Previous HWRF Forecast Interpolated Ahead 6 hr
JGSM	Japanese Global Spectral Model Forecast (rare)
JGSI	Previous JGSM Forecast Interpolated Ahead 6 hr
NAM	North American Mesoscale Model Forecast
NAMI	Previous NAM Forecast Interpolated Ahead 6 hr
NGPS / NGX	U.S. Navy NOGAPS Model Forecast (deprecated)
NGPI / NGXI	Previous NOGAPS Forecast Interpolated Ahead 6 hr (deprecated)
NVGM	U.S. Navy NAVGEM Model Forecast
NVGI	Previous NAVGEM Forecast Interpolated Ahead 6 hr

Consensus Models

These identifiers represent forecasts obtained from the average, or consensus, of multiple 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. Most consensus models run if at least two members are available.

IVCN	Variable Intensity Consensus of DSHP, LGEM, HWFI, GHMI, and CTCI Models
GUNA	Consensus of AVNI, GFDI, EGRI, and NGPI Model Track Forecasts
CGUN	Bias-Corrected GUNA Forecast
TCON / TCOE / TCOA	Consensus of AVNI, EGRI, GHMI, and HWFI Model Track Forecasts
TCCN	Bias-Corrected TCON Forecast
TVCN / TVCE / TVCA	Variable Consensus of AVNI, CTCI, EGRI, EMXI, GHMI, and HWFI Model Track Forecasts
TVCC	Bias-Corrected TVCN Forecast
TVCP	Variable Consensus of AVNI, CTCI, EGRI, GHMI, and HWFI Model Track Forecasts
TVCX	Variable Consensus of AVNI, CTCI, EMXI (2x weight), EGRI, GHMI, and HWFI Model Track Forecasts
TVCY	Variable Consensus of AVNI (2x weight), CTCI, EGRI, EMXI (2x weight), GHMI, and HWFI Model Track Forecasts
RYOC / MYOC	Forecaster-Generated Consensus Guidance (rare)

Statistical and Statistical-Dynamical Models

These identifiers represent forecasts obtained using statistical equations, whether those incorporating climatological information (purely statistical models) or those using simplified outputs from dynamical models (statistical-dynamical models). These models are less complex than the purely dynamical models described above; however, many of the intensity (but not track) models are as skillful, if not more skillful, than the more complex models. Models that are not skillful are typically not displayed on the forecast charts provided here.

BAMD	Deep-Layer Beta and Advection Model Track Forecast
TABD	Deep-Layer Trajectory and Beta Model Track Forecast
BAMM	Medium-Layer Beta and Advection Model Track Forecast
TABM	Medium-Layer Trajectory and Beta Model Track Forecast
BAMS	Shallow-Layer Beta and Advection Model Track Forecast
TABS	Shallow-Layer Trajectory and Beta Model Track Forecast
CLIP	72-hr Climatology and Persistence Track Forecast
CLP5	120-hr Climatology and Persistence Track Forecast
TCLP	168-hr Trajectory Climatology and Persistence Forecast (Track, Intensity)
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
OCD5	Operational CLP5 and DSHF Blended 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)
SPC3	Statistical Prediction of Intensity Forecast (six members)