Could any of y'all lead me in the right direction where I can find information on 'How to Read Computer Forecasting Models?' I've looked around a bit and haven't come up with anything. I think I'm pretty much on top of my game as far as the weather is concerned but I sure would like to take it a step further and learn these models a bit so I can give it a go on doing my own forecasting. I've got a ways to go but I've got to start somewhere. Any help would be great. Thanks!
Johnny
Models question....
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Models question....
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wxman57
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First thing
The first thing I'd do would be to go over to Pasch's ftp site (NHC forecaster) and read up on the various PowerPoint presentations he has there. In particular, the Comet case studies on the use of hurricane models in hurricane forecasting and the 3 "Models" powerpoints:
ftp://ftp.nhc.noaa.gov/pub/users/pasch/[url]
The PowerPoints on the NHC ftp site have A LOT of very useful info. [/url]
ftp://ftp.nhc.noaa.gov/pub/users/pasch/[url]
The PowerPoints on the NHC ftp site have A LOT of very useful info. [/url]
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JetMaxx
Here is a good model page I recommend for those interested in the tropics.
http://met.psu.edu/tropical/tcgengifs/
The basic global weather forecasting models are the GFS (once known as the AVN), and the ETA. However, the ETA doesn't seem to do very well with tropical systems, which is why Penn State doesn't use it on their tropical genesis site. GFS and ETA are run by NCEP/ NOAA/ NWS here in the U.S., while NOGAPS is a U.S. Navy forecast model. The CMC is also called the "Canadian" and is run by the Canadian meteorological service. The UKMET is from England...JMA the Japanese meteorological forecasting model. There is another global forecasting model available called the ECMWF or "Euro". It is only run once a day. It's not listed on the Penn State tropical genesis site, but is available on the Plymouth State University site, among others I've seen.
The basics to remember when forecasting tropical storms and hurricanes from model data...hurricanes are large low pressure centers. They tend to move toward lower pressure and usually skirt or steer around high pressure centers or ridges. A hurricane cannot go through a high pressure ridge to its north UNLESS the ridge breaks down (or weakens). Usually this occurs as troughs develop, and cold fronts push south and eastward into the weakening ridge.
Most Atlantic tropical systems and tropical cyclones move toward the west to WNW at low latitudes....below 20° N; being steered by the semi-permanent "Bermuda High" pressure ridge over the Atlantic waters east of the U.S. Once hurricanes move north of latitude 20°, many times they come under the influence of mid-latitude weather systems which usually begin the storm moving more poleward (NW then N) as they recurve around high pressure areas such as the Bermuda High.
The normal area where hurricane recurvature apex is reached (farthest west) is near latitude 30° north. Once a tropical storm or hurricane recurves and passes the apex, they often accelerate toward the NNE or NE in response to stronger winds aloft...also known as the Jet Stream.
The rule to remember on model watching...as long as high pressure remains north of the hurricane, it will likely continue moving W to WNW, skirting the southern edge of the ridge. When you see troughs to the west...and the western extent of the ridge...then you can expect the hurricane to begin recurving. The strength and depth of the trough and rate the ridge weakens/ erodes will determine the angle of recurvature (why most August hurricanes recurve gently, while October storms can turn sharply to the north and accelerate like Opal did in 1995).
PW
http://met.psu.edu/tropical/tcgengifs/
The basic global weather forecasting models are the GFS (once known as the AVN), and the ETA. However, the ETA doesn't seem to do very well with tropical systems, which is why Penn State doesn't use it on their tropical genesis site. GFS and ETA are run by NCEP/ NOAA/ NWS here in the U.S., while NOGAPS is a U.S. Navy forecast model. The CMC is also called the "Canadian" and is run by the Canadian meteorological service. The UKMET is from England...JMA the Japanese meteorological forecasting model. There is another global forecasting model available called the ECMWF or "Euro". It is only run once a day. It's not listed on the Penn State tropical genesis site, but is available on the Plymouth State University site, among others I've seen.
The basics to remember when forecasting tropical storms and hurricanes from model data...hurricanes are large low pressure centers. They tend to move toward lower pressure and usually skirt or steer around high pressure centers or ridges. A hurricane cannot go through a high pressure ridge to its north UNLESS the ridge breaks down (or weakens). Usually this occurs as troughs develop, and cold fronts push south and eastward into the weakening ridge.
Most Atlantic tropical systems and tropical cyclones move toward the west to WNW at low latitudes....below 20° N; being steered by the semi-permanent "Bermuda High" pressure ridge over the Atlantic waters east of the U.S. Once hurricanes move north of latitude 20°, many times they come under the influence of mid-latitude weather systems which usually begin the storm moving more poleward (NW then N) as they recurve around high pressure areas such as the Bermuda High.
The normal area where hurricane recurvature apex is reached (farthest west) is near latitude 30° north. Once a tropical storm or hurricane recurves and passes the apex, they often accelerate toward the NNE or NE in response to stronger winds aloft...also known as the Jet Stream.
The rule to remember on model watching...as long as high pressure remains north of the hurricane, it will likely continue moving W to WNW, skirting the southern edge of the ridge. When you see troughs to the west...and the western extent of the ridge...then you can expect the hurricane to begin recurving. The strength and depth of the trough and rate the ridge weakens/ erodes will determine the angle of recurvature (why most August hurricanes recurve gently, while October storms can turn sharply to the north and accelerate like Opal did in 1995).
PW
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Scott_inVA
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ticka1 wrote:BUMP - I have decided I am going to take one MODEL and try to learn how to read it and understand what its forecasting. Thanks wxman57 for the reference material.
Now my question - of all th models - which would be the best one for me to learn with?
Thanks,
Patricia
I don't know if learning a particular model is conceptually better than learning how they are developed, what they show (and don't show) and some basic science as to what it means.
If you want to learn a specific model, I'm w/Perry in suggestion the GFS (AVN) or the Eta.
Good luck and keep up posted, Ticka
Scott
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ALhurricane
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Here is a great page with several different learning modules...
http://meted.ucar.edu/topics_nwp.php
I went through these modules at the beginning of my senior year synoptic meteorology classes. They are a tremendous help.
Definitely check out the Model Fundamentals one and the Ten Common Misconceptions module. Very informative.
Hope this is of some help to those of you looking to learn more about models.
http://meted.ucar.edu/topics_nwp.php
I went through these modules at the beginning of my senior year synoptic meteorology classes. They are a tremendous help.
Definitely check out the Model Fundamentals one and the Ten Common Misconceptions module. Very informative.
Hope this is of some help to those of you looking to learn more about models.
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mf_dolphin
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Rainband