Today – Sunshine – High 64°
Windy though. North windy, therefore, kinda chilly.
Clouds will gather tonight. Ruh-roh.
Monday – Fog. Clouds. Rain – Wake Up 46°, High 56°
The opposite of Sunday.
We will wake up to patchy fog, or rain. NAM4 says: a lot of rain:
Rain should end in the evening, but by then, it should already be a washout. The GFS model has between 0.3″ and 0.5″:
The Euro model, which may have spent last night drinking, bullseyes one inch of rain. That’s super hard to believe. Our NWS forecasts 0.28″, which is still enough to rain out ball games Monday night.
Mid Week – Developing Storms
We clear out Tuesday, then all eyes turn to the west for Wednesday. SPC has already outlooked this area for severe thunderstorms, and we’re on the east side of it:
Weather models are in general agreement that a fast-moving line of showers and thunderstorms will arrive Wednesday night.
This line will be driven by a negatively tilted trough (that’s the bad/strong kind) . . .
. . . bombing out a surface low moving into the Great Lakes and trailing a strong cold front through the middle of the country.
The result: shear will be, to use NWS-Nashville’s words, “off the charts.” For weather nerds, deep layer shear between 60 and 75 kn, with 0-3 km helicity values between 500 and 600 m2/s2.
This can cause storms to rotate. The good news is that there won’t be much available “stuff” to rotate. The kindling for this fire will be sparse and short-lived.
This meager CAPE is the reason our tornado spidey senses are not tingling, at least not right now.
Therefore, the main concern is a straight line wind threat as the squall line arrives sometime late Wednesday night or early Thursday morning.
Now, all that said, if we see just a wee bit more CAPE (“stuff”) arrive ahead of the line, things could be worse. We have had really bad storms – including tornadoes – born from low CAPE.
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Categories: Forecast Blogs