Saturday 10/13 Special PM Discussion: On Severe Weather Watch

TONIGHT: I stood firm with 61 for tonight, and it looks on target or maybe just a bit too warm. I’ll go with it, but some spots may drop to the upper 50’s. Regardless, we’re definitely in the warm sector tonight.

SUNDAY: It’s a complex situation tomorrow. At this time, it does appear there will be enough wind shear for storms to form, but the instability is actually more marginal. That’s typical of fall events, as storm development takes less destabilization than it would in say, early May. The Storm Prediction Center kept us in a 15 percent SLIGHT RISK for tomorrow. We will be back into the low 70’s which may also help instability. IF, as I currently expect and SPC and others have mentioned, a squall line were to form (which would probably occur in the early afternoon to the west), then damaging winds would be considered the primary threat. Hail and tornadoes are also possible. The best threat is between 2 PM and 8 PM, and that’s especially true west of a line from Wilmington, OH to Georgetown, OH to Brooksville, Kentucky. Once you get east of that line (Highland, Adams, Mason and Lewis counties), the atmosphere will have begun to stabilize as the storms move in, but even here there’s still a severe weather threat.

Another concern is strong winds ahead of the line of storms that should form. Upper level winds appear to be around 45 knots at 850 millibars, or about 5000 feet and near 65 knots at 500 millibars or 18,000 feet. That’s concerning because with the heating of the day, we can mix those winds down to the surface. There will also be a tight pressure gradient especially north and west of here. If that gradient moves southeast, and we mix those upper level winds down a bit, we’d have potential for minor wind damage even before the storms come in. Something to watch, for sure. In fact the National Weather Service at Indianapolis has a Wind Advisory out for parts of their area tomorrow for this reason.

MONDAY: Back to dry conditions and highs around 65 on Monday afternoon, after starting with lows in the mid 40’s.

TUESDAY AND WEDNESDAY: As of right now, I’ll leave us dry with highs in the low 70’s and lows in the upper 40’s.

THURSDAY-SATURDAY: Looking like another complex situation. I put in the rain chance for Thursday with the PM discussion this past Thursday, and for Friday this morning. Now, it looks like Saturday we’ll be under the influence of an upper low, and so…sigh…the chance of showers needs to be added for this period as well. Highs will be in the lower to middle 60’s.

SOCIAL MEDIA: Follow along as I watch our skies and, as warranted, our streets:

NKYWx on Facebook
NKYWx on Twitter

NEXT UPDATE: Because of the concerns about afternoon storms and even the winds before that, I will be here all day tomorrow. There will be frequent updates all day on social media, and the next blog update will be before 9 AM Sunday. Until then, take care!

Jeremy

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