Go or No: staying out of the ice

It’s December and you live in Albany, New York, so it’s no surprise there’s snow in the forecast today, but you’re more focused on the aviation weather than the chance of a few inches on the ground. Your plan today is to fly your 1980 Piper Aztec from ALB to BKL in Cleveland, Ohio. You fly 200 hours per year in the trusty Aztec, so you’re experienced and instrument proficient. Will the weather cooperate today? Read the forecast below and add a comment explaining your thought process and your decision. Your estimated time of departure is 9 am eastern, 1400Z.

Overview

The radar image in ForeFlight shows snow to the west of Albany, with more to the north. As you approach western Pennsylvania and northern Ohio, the snow disappears, then changes over to rain. There appear to be IFR ceilings to the north, but VFR along most of your route and south.

The surface analysis shows a low pressure system and associated cold front moving across the Midwest, which seems to be driving the weather.

The prog charts show the front moving fairly quickly across the eastern half of the United States, but there’s definitely snow on the way for New York.

The forecast for tomorrow morning shows the front east of ALB.

Satellite

The radar shows nothing convective, but lots of precipitation. That means icing is the main concern today—your Aztec has hot props and boots but not a full deice package. A look at the satellite picture might help determine how tall the clouds are and how widespread they are. First up is the infrared image, which shows clouds across your entire route, with some higher tops in Ohio.

The visible satellite confirms that overall impression.

Icing

You’re used to studying icing forecasts, so the next step is to dive into all those charts. First, a look at the Graphical AIRMET is in order. It shows the potential for icing between 8,000 and 17,000 along most of your route, with icing lower to the north.

Next is the freezing level chart – is there any chance  you can stay above freezing today?

Next up is the icing forecast map layer in ForeFlight, an excellent tool that shows the forecast severity of icing at different altitudes. At 4,000 feet the exposure seems fairly minor.

At 6,000 feet you might still be below the icing according to the AIRMET, but the chart is less clear.

The 8,000 foot map layer shows a less enticing picture, but the worst is clearly to the north of your route. There might be a southerly route that would avoid some of the darker blue.

While those ForeFlight charts are helpful, they show potential icing severity. It’s also helpful to look at icing probability – what the chances are of encountering icing, not whether it will be light/moderate/severe. First up is the 5,000 foot image.

Next is the 7,000 foot image, which shows some icing over most of New York, but a fairly clear route over Pennsylvania and Ohio.

The last step in the icing review is to look at Pilot Reports (PIREPs). There are a number of them, most of them showing ice starting between 8,000 and 9,000 feet, with tops in the mid-teens.

Text weather

That’s a look at the weather aloft; the last step is to consider surface weather. Albany right now is showing good VFR conditions, but the forecast is not as good.

At Burke Lakefront in Cleveland, conditions are good and forecast to stay that way.

Decision time

It’s time to make the call. Yes, there is icing in the forecast, but that’s true six months of the year in New York. You could go to Cleveland at 6,000 or even 4,000 feet and try to stay under the ice or you could plan a route that goes south of the heavier snow. But then again, ice is not to be messed with and the weather looks better tomorrow. Is it a go or no go?

What would you do? Add a comment below.

27 Comments

  • Straight forward trip in an Aztec through Upstate New York and into Ohio. Could make the entire trip at 4,000′ if necessary. And there are plenty of outs to the south as well. Many times, the icing forecast through this area is more conservative than reality. Once past Elmira, the snow quits and it’ an easy ride into BKL.

  • This is close to home for me–I’ve often flown over Albany on my way between Ottawa and Boston or NY in the winter.

    Without looking at all the different products, that high-pressure system moving east over the Great Lakes makes me nervous. If it starts drawing cold air in from the northwest, I think the pilot will see more lake-effect weather than forecast south/southeast of the lakes, along their route.

    I don’t mind lake effect if I’m just flying over it for a short while, with CAVU on both ends (like NY to Ottawa), but not if I’m going to be flying along it. I’m out.

  • Is there a Skew-T chart available to add to the mix of provided charts? Would be helpful chart to reference when an analysis of atmospheric levels/layers is being considered.

  • Do you really need to get there today? A delay of 24 hours and a better forecast would be my choice. Bouncing along at 4,000, plus the chance of icing makes it a delay for me.

  • The PIREPs and forecasts indicate “known icing” conditions. As the aircraft is not approved for flight into known icing the planned flight likely violates FARs at 6,000’. Flying south towards Stewart at 4,000’ then westward along the VMC fields might be acceptable, but the airway MEAs are higher than that. Better plan is to wait for the cold front to pass and fly tomorrow.

  • COULD WAIT UNTIL TOMORROW AS THE MOST CONSERVATIVE CHOICE BUT COULD GO AT 4-6000 STAYING IN THE CLEAR AND TEMP IN CLEVE IS 46 ON THE GROUND. LOTS OF OUTS TO THE SOUTH/ CONSIDER LANDING IF WORSE THAN FORCAST MAY WANT TO CHECK WEATHER AT INTERMEDIATE AIRPORTS AS ALTERNATES.

  • I would go by filing for 6000 but with a firm plan to fly at 4000 or a more southerly route if conditions are worsening en route.

  • Wait 24 hours. I don’t like any plan that counts on flying a trip at 4,000′ as a possible way to go. Nothing positive about flying a cross country trip at low altitudes, even with a twin engine airplane.

    The possibility of the high pressure system causing lake effect weather even makes the 4,000′ solution a non factor.

    For full non-disclosure – I have had icing “issues” twice and with one time a pretty bad case of it to where if I was not able to land on a RNAV approach with weather to minimums there was no way that my airplane was going to make it on a missed approach. I was loaded with ice and coming down regardless.

    And both times I picked up the icing within a forecast of ZERO chances of ice, which is what we have to have anyway to legally be able to fly airplanes that are not certified for FIKI.

    • Agree. Same thing happened to me in a C-421. All I could do was descend on the ILS which was below minimums. No way we could go missed

  • Only needed to see the first radar picture of the weather. No way would I fly an Aztec on that route. I would only fly a light single engine aircraft in the winter if there is zero precipitation on my route and high ceilings ie greater than 8000 feet.

  • I have a similarly equipped A36TC – boots and hot prop but not FIKI certified. I’d go. Like others said, plenty of outs. But if I were flying over mountains or large bodies of water, I’d probably wait a day. This is one of those 51/49 decisions where choosing not to go is also quite reasonable.

  • No. The 1600Z forecast is what scares me. If I know I can fly under the freezing level VFR then OK. Minimum IFR is 6000 ft so there is a chance of ice. Any chance of a IFR approach in the hills with ice no way. If it was flat to the South maybe.

  • It’s been a while since I’ve flown piston twins. Chieftain GoldenEagle etc. Light trace or light mixed is workable. I’d go south if I were to take the flight. Pilot reports are often more important than forecast models. If I heard anything approaching moderate I’d figure a better route or wait. Just know your airplane’s limitations. And your own.

  • I would wait 24 hours. I have 24k+ total time. I think that is because I dont fly that type aircraft in that type weather.

  • I do not entirely trust the presented icing forecasts—AIRMET is 2 hours prior to departure, and the ForeFlight forecast has no time stamp. The fast-moving cold front will pick up moisture from the lakes, bring in precipitation, and lower the freezing level, maybe even to the surface. Suspect the icing will be worse than forecast. Tomorrow chances look much better.

  • Great exercise !
    So what was the actual outcome vs. forecast? Inquiring minds want to know ! (to get a sense of real-life reliability of Wx forecasts)

    • The outcome was pretty close to forecast – the next METAR at ALB (1451Z) was still pretty good: 17005KT 10SM -SN OVC070. But half an hour later, the snow moved in for real: 16009KT 1 1/2SM -SN BKN034 BKN039 OVC055 .

      The radar picture is here: https://airfactsjournal.com/files/2019/12/Screen-Shot-2019-12-16-at-9.20.37-AM.png

      The weather in Cleveland was windy but still VFR: 31019KT 10SM SCT016 BKN031 OVC041.

      PIREPs were popping up for icing throughout the morning. Lots of ice between 9,000 and 15,000 feet, with some light icing reports around 7,000.

      This was a 50/50 trip for us (that’s the point!). There was a route to the south that most likely would have worked pretty well, especially at 6,000. But it was not a pleasant day to fly.

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