Today's Forecast Pros and Cons

Interesting forecast challenge for today and tomorrow and I'll try to summarize briefly because I have other obligations this morning.

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PROS - We finally will have an excellent wind shear profile in place this afternoon and evening for organized severe thunderstorms to move into low elevations (I think that this will be far and away the best winds aloft setting of the summer so far).

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With last night's outflows, light rains, and moisture recycling, the Tucson sounding will likely have CAPE, and perhaps at moderate levels, by late afternoon. PW values are up in southern Arizona, and Yuma has seen a new upsurge in Td and is currently in low 70sF.

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There are a number of inverted troughs at various levels and these are also interacting with a tropical wave that is south of the GoC. The NAM 500 mb forecast for midnight tonight shows this well and indicates that the best vorticity max should be over northern Sonora. The 200 mb NAM forecast for midnight (bottom) indicates westerly winds aloft and perhaps some difluence over southeast Arizona.

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All the debris cloudiness is to the south to west, and skies will be mostly clear through the heat-up time of day.
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There should be good good convegent wind flows again during the late afternoon with northwesterlies from the low deserts possibly meeting organized outflows.

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CONS - The best subtropical moisture remains south over Mexico.

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The Tucson sounding indicates significant low-level cooling to overcome. Additionally, the sounding this morning is too moist by about 4 mm wrt GPS values, so the CAPE situation may not be as positive as I wrote above. Fortunately, there were not widespread or significant rains during past 24-hours, except far to the east, so that most insolation should go to heating up the boundary layer.

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The models continue to indicate that there will be more storms and rainfall tomorrow, rather than today.

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FORECAST - my forecast is that today there will be an elevated threat of severe thunderstorms with damaging winds, and that organized lines and outflows are likely. Rains will be better than yesterday. Tomorrow will have to await today's outcomes.