I’ve uttered the statement in the post title a number of times, usually to new chasers. It’s not enough to be in the right place to intercept a storm. One has to be there at the right time as well.

Wednesday’s setup is a prime example of this. First, here’s the SPC Day 2 convective outlook covering tomorrow:day2otlk_0700

Just the fact that the SPC forecasters have issued a Marginal Risk for Virginia in February is encouraging for local chasers. However after delving into the details the setup doesn’t look very promising.

First – per the this morning’s 12Z NAM – here’s the surface low progged to form along the cold front over eastern KY and TN:namma_sfc_temp_036

Note the time on the graphic: 0Z Thursday (or 7 pm Wednesday). That’s after dark so keep that in mind.

Now here’s the 700 mb (~10,000 ft) vertical velocity graphic for the same time:namma_700_vvel_036

The only convective lifting mechanism visible in this graphic is – you guessed it – the surface low that is forming courtesy of an upper level vorticity center scooting across the Midwest. Again, note the time: 7 pm Wednesday.

And one more graphic, this being the 12Z 4 km NAM graphic showing simulated radar returns at 10 pm Wednesday:nam4kmma_prec_radar_039

Precipitation is finally breaking out over the Virginia Piedmont ahead of the low and associated cold front…but this is well after dark tomorrow night. Following the model data out further in time the available instability and shear reach a (limited) maximum after midnight across the Piedmont.

Other models (GFS and several WRF models) support this timing. So given that night chasing is out of my bailiwick the conclusion is that I’m not going out tomorrow unless things change drastically in this evening’s model runs. Hence the blog post title.

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