Bufkit Questions

[chrispt]

So I've started digging into Bufkit and had a few questions:

- When looking at the P-Type tab, specifically under thickness, can one deduce what kind of precipitation is occurring at ground level?
- So, if say my largest dot is under R, then can I assume that it is probably raining at the ground?
- I know that the Skew-T will show what I assume it interpolates as the precipitation on the left-hand side (Green R, Blue S, etc.) with the varying intensities. Should this be taken over what is seen on the P-Type chart?

 

[Robert Dewey]

I have noticed some discrepancies in the p-type algorithms, especially if you're close to the R/IP/ZR/SN lines. For example, when using the "overview" mode, I would see areas as showing snow when 800-900mb temps would be >=1C, or freezing rain (not drizzle) where the entire profile is <0C. It's usually better if I switch to the Bourgouin p-type algorithm. I have also noticed the thickness/energy algorithms don't always match up either. Again, that's usually only for fringe cases... and in such cases the accuracy of the thermal profile depicted by the model can be just as much of a headache, especially when you're talking about a variation in T of ~0.5C at 12 hours out. Models usually aren't THAT accurate, and it comes down to recognizing local patterns for specific events (rain vs ice storms, etc).

To be honest, I'm not sure which algorithm is better, if any... I'm sure they all perform differently under different cases, which is why they are included in BUFKIT... to sort of give you a look at all potential possibilities.

 

[rdale]

The Cobb method is much better. It's on the overview screen.

 

[chrispt]

I see the option there, but not sure how it's used. Any insight?

 

[GPhillips]

Cobb is actually a liquid water to snow ratio tool that depends on vertical motion in the dendritic growth zone. Strong upward vertical motion in the -12 to -18 C layer will result in a high ratio. It's included along with other liquid to snow ratio "tools".