ST. PETERSBURG, Fla. (AP) — When forecasters from the National Weather Service track a hurricane, they use models from several different supercomputers located around the world to create their predictions.

Some of those models are more accurate than others. During Hurricane Sandy last October, for instance, the model from the European Center for Medium-range Weather Forecasting in the United Kingdom predicted eight days before landfall that the large storm would hit the East Coast, while the American supercomputer model showed Sandy drifting out to sea.

The American model eventually predicted Sandy's landfall four days before the storm hit — plenty of time for preparation — but revealed a potential weakness in the American computer compared to the European system. It left some meteorologists fuming.

"Let me be blunt: the state of operational U.S. numerical weather prediction is an embarrassment to the nation and it does not have to be this way," wrote Cliff Maas, a professor of atmospheric sciences at the University of Washington on his weather blog.

Meteorologists agree that the two American supercomputers that provide storm models are underpowered — which is why the National Weather Service plans on upgrading those computers in the next two years. The two main forecasting computers — one in Orlando, Fla. and the other in Reston, Va., — will receive $25 million in upgrades as part of the Hurricane Sandy supplemental bill that was recently approved by Congress.

"This will improve weather forecasting across the board," said Christopher Vaccaro, a spokesman for the National Oceanic and Atmospheric Administration. "Certainly one area of concern that has received some attention were these larger high-impact extreme weather events. The European model is able to pick up on those storms earlier than our model."

Jeff Masters, meteorology director at the online forecasting service Weather Underground, said that other than Hurricane Sandy, the American model outperformed the European model during the 2012 hurricane season — but if you look at a three-year period, the European model still comes out on top.

"If the U.S. did invest more money and people into making the model better, then the forecast would be better," Masters said. "The money we spend on weather forecasts and improving them pays for itself."

Types of hurricane forecasting models

The best hurricane forecasting models we have are "global" models that solve the mathematical equations governing the behavior of the atmosphere at every point on the globe. Models that solve these equations are called "dynamical" models. The four best hurricane forecast models—ECMWF, GFDL, GFS, and UKMET—are all global dynamical models. These models take several hours to run on the world's most advanced supercomputers.

There are also dynamical models that cover just a portion of the globe. These are less useful, unless the hurricane happens to start out inside the domain the model covers and stay there. Hurricanes moving from outside the model domain into the model domain are not well handled. An example of this kind of model is the NAM model covering North America and the surrounding waters, run by the National Weather Service (NWS).

Another type of hurricane model is a statistical model. These models do not try to solve mathematical equations on a grid. The advantage of these statistical models is that they are fast to run and can provide output in a few minutes. There are also hybrid statistical/dynamical models, and simple trajectory models.

A full list of all of the tropical cyclone track and intensity models can be found on the National Hurricane Center's website.

A summary of the top six models:

ECMWF: The European Center for Medium-Range Weather Forecasting (ECMWF) model is the premier global model in the world for medium range weather forecasting in the mid-latitudes. In 2006, the ECMWF made improvements that starting producing very accurate hurricanes forecasts.

GFS: The Global Forecast System model run by the NWS. Excellent graphics are available on the web from the National Center for Environmental Prediction. Wunderground.com also has GFS plots. I like the Tropical Atlantic imagery. If you select "Shear" from the "level" menu, then click on "Add a Map", you'll get plots of the wind shear that I talk so much about.

GFDL: The NWS/Geophysical Fluid Dynamics Laboratory model. The GFDL and HWRF models are the only models that provide specific intensity forecasts of hurricanes. Wunderground.com makes these graphics available on Wundermap. More detailed GFDL graphics are available at NOAA/NCEP. See the "GHM" model under the heading, Hurricane Graphics.

UKMET: The United Kingdom Met Office model. Data from this model is restricted from being redistributed according to international agreement, and graphics from the UKMET are difficult to find on the web. Only paying subscribers are supposed to have access to the data.

HWRF: The NWS/Hurricane Weather Research Model. HWRF is a non-hydrostatic a coupled ocean-atmosphere model, will utilize highly advanced physics of the atmosphere, ocean and waves in one prediction system, providing unparalleled understanding of the science of tropical cyclone evolution. Its output gives meteorologists an analysis of the hurricane in three-dimensions from real-time airborne Doppler radar. It will make use of a wide variety of observations from satellites, data buoys, and hurricane hunter aircraft. No other hurricane model accesses this wide of a range of meteorological information. The GFDL and HWRF models are the only models that provide specific intensity forecasts of hurricanes. Detailed HWRF graphics are available at NOAA/NCEP. See the "HWRF" model under the heading, Hurricane Graphics.

NOGAPS: The U.S. Navy's Navy Operational Global Prediction Center System. Graphics are available at the Navy web site. This model has been performing poorly in recent years compared to the other global models, so it has been removed from the consensus models that the National hurricane Center uses as of 2011.

One other model worth looking at, but not as good as the other six is the Canadian GEM model.

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Oklahoma is unprepared for Tornadoes.  When they get hit by one or something like one... they go crazy and call it a "tornado outbreak" as if it's unusual... and therefore they can continue being unprepared.

The only reason I'm annoyed by the Tornado BS is that it perpetuates the unpreparedness of Oklahoma and thus the next tornado to hit them will be just as bad and they won't realize they need to prepare for such things then either.

What the news should have been saying is... This is not unusual. All this damage could have been prevented.  Wake up and get prepared for the next one.  

Instead they go on about the tornado and how nothing in the world could have prepared them for it... when that's entirely false.  

Quoted:
Colorado is unprepared for wildfires.  When they get hit by one or something like one... they go crazy and call it a "massive wildfire" as if it's unusual... and therefore they can continue being unprepared.

The only reason I'm annoyed by the Wildfire BS is that it perpetuates the unpreparedness of Colorado and thus the next wildfire to hit them will be just as bad and they won't realize they need to prepare for such things then either.

What the news should have been saying is... This is not unusual. All this damage could have been prevented.  Wake up and get prepared for the next one.  

Instead they go on about the wildfire and how nothing in the world could have prepared them for it... when that's entirely false.  

Quoted:
California is unprepared for earthquakes.  When they get hit by one or something like one... they go crazy and call it a "killer quake" as if it's unusual... and therefore they can continue being unprepared.

The only reason I'm annoyed by the Earthquake BS is that it perpetuates the unpreparedness of California and thus the next earthquake to hit them will be just as bad and they won't realize they need to prepare for such things then either.

What the news should have been saying is... This is not unusual. All this damage could have been prevented.  Wake up and get prepared for the next one.  

Instead they go on about the earthquake and how nothing in the world could have prepared them for it... when that's entirely false.