wxteam4's Blog

With all the heat and humidity that built up over the past two days...you'd think that storms would be firing up right on top of us....but the air aloft is quite warm as well...so that has prevented activity from initiating so far. IF the storms out there keep weakening...they may be DOA tomorrow morning...but for those hoping for some showers...all hope is not lost.

Radar trends have shown quite a bit of weakening of the storms over north-central Kansas this evening. The low level flow is so warm, and the updrafts so anemic, that the rain cooled air is not quite enough to keep the storms alive and healthy.  The cold pool uner the rain cooled air has formed, and as a result,  the boundary is making slow but sure  progress toward Kansas City, which will gradually increase the low level moisture convergence.  The evening sounding also showed an elevated layer of well mixed air and precipitable water readings at or above 1.50", so the juice is there...we just need the spark, to keep the rain alive, or re-initiate rainfall tomorrow if the storms out west fizzle before arrival overnight.

Unfortunately the upper air support is pretty weak. Temperatures at 18,000 feet were around -5C (23 F) which is pretty warm for air at that level.  Plus between 10,000 and 30,000 feet the highest wid speeds were only 30 knots ( 34.6 mph)  Those speeds can sustain some weak updrafts...but until the air up there cools...or the speeds and divergence increases...we can expect any rain that does arrive to be less than impressive.

Wind speeds aloft are progged to increase gradually tomorrow, which should increse updraft potential across the area.  It's looking as if the morning hours could see some spotty elevated showers...with a  rumble of thunder possible. The boundary should drift across the area, nearly stalling to our south in the afternoon...then storms should redevelop along the boundary in the afternoon as southern Missouri heats up in to the 90s again...creating a strong inflow zone just to our south.  So it's likely that the heaviest of the rainfall will skip over the metro area...and we'll end up with quite a bit less rainfall than areas to our northwest tonight....and to our southeast tomorrow afternoon.

By Wednesday the boudary will be far enough south, that storm chances will be all but gone...however with a 300 mb jet overhead, and slightly better lapse rates...an isolated storms can;t be ruled out.  After that...it's back to sunshine and warmer air for the weekend!

By the way, I refer to the "boundary" heading our way as such, because it is not a true "front" which would imply that we are changing air masses.  The true cold frontal boundaries will be far to our north, and not make inroads this far south.  While temperatures will be cooler the next couple of days...it will be as a result of the cloud cover...not an airmass change.  The density of the air will not change dramatically, nor will the thckness of the atmpsphere.  Sometimes these trofs are incorrectly called a front.  Just a little met 101 lesson for you tonight. Identifying the airmass is a key to forecasting!

Have a wonderful Tuesday!

Mike