Go or No Go: over the ice at night?

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Today’s mission is to fly from Duluth, Minnesota (DLH), to your home in Columbus, Ohio (OSU). It’s nearly 5pm in Duluth, so this flight will be completely in the dark. That’s not a a deal-breaker, since you typically log about a third of your hours at night and are instrument proficient. Your airplane is a Cirrus SR22T, with a full Garmin G1000 glass cockpit, autopilot, and datalink weather. Your ETD is 2300Z and your flight should take a little less than three hours.

Read the weather briefing below and tell us if you would take off or cancel.

Overview

The weather in Duluth looks pretty good, but the Maps page in ForeFlight shows some snow in the Chicago area and a number of those pesky blue PIREPs.

The surface analysis shows the underlying cause of that precipitation: a weak low is sitting over southern Minnesota, with a warm front extending east over Michigan.

The prognostic charts show the snow moving off to the east overnight, with the worst over northeast Ohio. So it looks like you’ll be flying on the backside of this small system.

By tomorrow morning there are some leftover snow showers in Ohio but most of the precipitation is gone.

Radar and satellite

The radar image doesn’t show much other than those scattered snow showers in southern Wisconsin and northern Illinois.

The satellite image shows clouds along most of your route, with the thickest clouds in Wisconsin.

The cloud top forecast indicates mid-level tops over much of your route, with the highest tops around 14,000 feet. With your turbo Cirrus, cruising at 15,000 or 17,000 feet is perfectly acceptable.

Icing

With no convective activity and no major issues with turbulence (all the AIRMETs are for bumps above 18,000 feet), the main concern today is in-flight icing—no surprise for a flight in January over the Midwest. To start, you look at the G-AIRMET for icing, which shows icing from the surface to 10,000 feet along most of your route (at a forecast time of 0000Z).


The forecast icing layer in ForeFlight makes it easy to compare potential icing at different altitudes. Not surprisingly, it mostly agrees with the AIRMET, showing moderate ice over Chicago at 10,000 feet. But your departure and destination look relatively ice-free.

At 12,000 feet, conditions seem to be improving, with most of the ice off to the east.

By 14,000 feet it seems like you’d be out of any icing.

PIREPs

The next step is to dig into those PIREPs you saw on your first look at the Maps page. The icing PIREP overview shows plenty of green symbols.

It’s important to go beyond the raw numbers though, as often a PIREP will include other details about cloud tops or OAT. First is a report in Wisconsin, showing light rime at 11,000 feet.

Another PIREP near Chicago shows light rime from 11,000 to 11,500 feet.

To the east of Chicago, it seems like the icing is worse, with multiple reports of moderate ice, including this one at 10,000.

Finally, over northern Indiana a King Air reported light ice from 10,100 down to 6,000 feet but also that tops were at 10,100 feet.

Text weather

Finally, you’ll want to check the METARs and TAFs. Duluth is reporting good VFR (but cold!) and it’s forecast to stay that way. You should have a VFR takeoff and climb.

Columbus is reporting good VFR conditions now, although the forecast calls for some snow showers to move in closer to your arrival time.

Decision time

It’s time to make the call: go or no go? On the one hand, weather at your departure and destination look pretty good, and you should be able to get above the ice. On the other hand, it will be dark and there is definitely some precipitation to consider about halfway along your route, plus all those icing PIREPs.

Add a comment below and tell us what you would do. Here’s one final twist: would TKS deice change your plan? Most SR22Ts have this system, some of them certified for flight into known icing. Does that matter for your decision making?

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