...like a cold, dead lamb. For the Friday-Monday period, the strongest conditions were probably mid to late yesterday afternoon when the overdevelopment finally broke up, and we had a great cumulus cloud field at ~ 6K...reflected in last night's sounding. There's no stabilizing warm air advection aloft, a great dew point spread, and strong late April sun, so today could have been another diamond day (like Wednesday), but...the accursed cirrus issue. All models (and they are fresh now) have total southern tier coverage, all above 15k and all day long. How big a problem? Depends on how thick they are. That depends on how much synoptic-scale ascent at those levels. And that...is beyond the capability of the current modeling state of the art to predict. If you have a pot of water simmering, it only take a little more heat to get a rolling boil. If the cirrus is thin enough, enough sun could get through to make for decent life..."grey" thermals if you will, 'cause they probably won't reach the CCL. If the cirrus are just a little thicker, which only requires a few more centimeters/sec lift and beyond model vertical velocity resolution, it will be difficult to get your hour. Only way to know is to fly.
Tomorrow: no cirrus issue at all. No WAA problem, winds surface and aloft staying pretty much NW. Dew point depression ~ 30F in the afternoon. Strong thermals to 6K? Well, there should be. The vertical wind profile isn't backing with altitude (WAA), but it isn't veering either (which would mean strong cold advection and strong lift). Again, only way to know is get up there.
Monday: sorry Mark, the freaking cirrus return! By then, we will be on the back side of the high, definite WAA, unfortunately but necessarily coupled with cirrus. A cold (for late April), pretty much dead day, wrt both surface wind and lift. If the 60-72 hour models verify...and sure as hell hope they don't.
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