What do those lines and dots mean on top of the storm?

[ilovecornfields]

I’ve noticed on ForeFlight sometimes the storm will have a line extending from it and four dots (circled in read). Does anyone know what they mean? Is that the predicted storm track at a certain time interval?

[Ned Gravel]

Those are lines predicting the path of the storm cell shown at the current point of origin.  The dots indicate time of travel.  I think they indicate predicted locations in 20 minute increments, but I could be wrong on that.  

[ragedracer1977]

3 hours ago, Ned Gravel said:

Those are lines predicting the path of the storm cell shown at the current point of origin.  The dots indicate time of travel.  I think they indicate predicted locations in 20 minute increments, but I could be wrong on that.  

You’re correct.  First dot is present position, then predicted position in 20,40, and 60 minutes 

[201Steve]

@Scott Dennstaedt, PhD

[Scott Dennstaedt, PhD]

I don't use FF, so can't really help.  Suggest looking at the FF pilots guide for info.  

[Rick Junkin]

@Ned Gravel and @ragedracer1977 are correct. It is only mentioned in one place in Foreflight documentation, in the Foreflight Legends Guide on page 17. There are references in the main Foreflight Mobile Pilot’s Guide to the XM storm cell predictions but nothing about the internal Foreflight storm track prediction capability.

Cheers,
Rick

[jlunseth]

I would add that for our purposes, which are primarily Tcell avoidance, those lines are not particularly accurate. They appear to be track at a given moment in time, but actual track is different. Those lines are just general indicators. From my observation the track lines move around quite a bit over time and a strong cell moving along a track at one moment may degrade and disappear, or blossom and expand in multiple directions at the same time. Generally, in our area, actual track tends to be more easterly than the track lines. Not saying they are not useful, but if you are trying to track around a cell they are not exact either.

[N201MKTurbo]

The only thing they are good for while up flying is for making decisions about which way to deviate around a cell. If the lines are pointing to the right deviate to the left and visa versa.

[The Other Red Baron]

Now they have a completely new radar feed without lowest tilt and no more 4 dots it looks like.  Now there are echo tops and an arrow.   I'm starting to have a difficult time justifying the $240/year for pro plus.  I found lowest tilt extremely useful when flying or on the ground.

[rbp]

given how long the radar lag is (15-20 minutes), its probably safer to downgrade the image so people don't use it for cell avoidance. (note to all: I am not talking about you or anyone in particular)

[N201MKTurbo]

42 minutes ago, rbp said:

given how long the radar lag is (15-20 minutes), its probably safer to downgrade the image so people don't use it for cell avoidance. (note to all: I am not talking about you or anyone in particular)

I thought it updated every six minutes on the ground, or are you talking about ADS-B radar? You can’t blame ForeFlight for that. 

[rbp]

27 minutes ago, N201MKTurbo said:

I thought it updated every six minutes on the ground, or are you talking about ADS-B radar? You can’t blame ForeFlight for that. 

I'm not "blaming foreflight". i'm concerned about pilots who mistake higher resolution images for for higher accuracy, in weather images that could be tens of minutes old. I'm saying that degraded images will hopefully dissuade those pilots to use the up/downlinked images to fly between the cells.

[N201MKTurbo]

2 minutes ago, rbp said:

I'm not "blaming foreflight". i'm concerned about pilots who mistake higher resolution images for for higher accuracy, in weather images that could be tens of minutes old. I'm saying that degraded images will hopefully dissuade those pilots to use the up/downlinked images to fly between the cells.

Trying to split cells with ADS-B radar in IMC would be a fools game no matter what the resolution. I just use it to figure the best direction to deviate. I would be very hesitant to try to pick my way through a line of cells with onboard radar. Twice I have been in the center of a thunder storms cell IMC. I don’t want to go back BTDT.

[rbp]

1 minute ago, N201MKTurbo said:

Trying to split cells with ADS-B radar in IMC would be a fools game no matter what the resolution. I just use it to figure the best direction to deviate. I would be very hesitant to try to pick my way through a line of cells with onboard radar. Twice I have been in the center of a thunder storms cell IMC. I don’t want to go back BTDT.

this exactly.  

 

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