Go or No Go: cut-off low conundrum

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After a beautiful early fall in Ohio, a cut-off low has installed itself over the southeastern United States and brought with it rain, storms, and IFR conditions. Flying conditions have been marginal all week, but you need to get to Nashville from your home outside Cincinnati, so you’ve been trying to pick the right time. It’s a two hour trip in your Cessna 182—is this the right time? Read the weather briefing below, then add a comment and tell us if it’s a go or a no-go for you. You are instrument rated and your proposed departure time is 1330Z.

Overview

The Map page in ForeFlight shows scattered rain and IFR conditions across your route of flight, but at least there’s not a solid wall of thunderstorms like there was yesterday.

GNG I69 JWN route - Go or No Go: cut-off low conundrum

The driving force behind all this weather is that cut-off low aloft. It’s been spinning over Missouri for days now.

GNG 500mb - Go or No Go: cut-off low conundrum

The result is an ugly surface analysis, with a warm front and a stationary front draped across the Midwest and Southeast.

GNG surf ana - Go or No Go: cut-off low conundrum

The prog charts suggest the weather might finally start to move east today, but only very slowly.

GNG 18Z chart - Go or No Go: cut-off low conundrum

Even tonight, there is plenty of rain forecast along that front.

GNG 00Z chart scaled - Go or No Go: cut-off low conundrum

Radar and satellite

Step one today is to get a handle on that rain: is there any convection to watch out for? The Convective SIGMET map certainly thinks it’s possible, although there is only an outlook box along your route.

CSIGMET - Go or No Go: cut-off low conundrum

The regional radar shows fairly scattered rain around Cincinnati.

GNG radar north - Go or No Go: cut-off low conundrum

Closer to Nashville, it looks like the rain breaks up.

GNG radar south - Go or No Go: cut-off low conundrum

The infrared satellite image shows fairly thick clouds in Ohio, but nothing major in the western half of Kentucky or Tennessee.

GNG satellite IR - Go or No Go: cut-off low conundrum

Icing

It is early October, so it’s definitely icing season. There are some AIRMETs for in-flight icing, but they are at higher altitudes.

GNG ice AIRMET - Go or No Go: cut-off low conundrum

A look at the freezing levels shows a flight at your typical 8-10,000 ft. altitude should be above freezing.

GNG freezing level - Go or No Go: cut-off low conundrum

The forecast icing product shows no threat at 11,000 feet (although it does start at 13,000).

GNG ice 11k - Go or No Go: cut-off low conundrum

Finally, the cloud forecast map offers some good news. Tops seem to be fairly low along your route, so it looks like you might get on top—especially closer to your destination.

GNG cloud - Go or No Go: cut-off low conundrum

Text weather

Your departure airport is showing pretty solid IFR conditions, but is forecast to improve.

GNG I69 weather - Go or No Go: cut-off low conundrum

En route, conditions appear to be pretty good VFR, with broken layers and no rain.

GNG en route KY - Go or No Go: cut-off low conundrum

In Nashville, it’s marginal VFR and forecast to stay pretty much the same, although it should clear up later in the day.

GNG JWN weather - Go or No Go: cut-off low conundrum

Some pilot reports are also worth noting. They suggest the tops are right around your cruising altitude near Cincinnati.

GNG PIREPs - Go or No Go: cut-off low conundrum

Decision time

It’s time to make the call. Your goal was to get airborne during the morning, before any of the day’s heat can make those rain showers thunderstorms. Right now that looks to be the case, with mostly rain and layered clouds along your route. But will it stay that way? Does that front have any other surprises?

Add your comment below.

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