Go or No Go: a gap in the weather?

You bought your Cirrus SR22 for business, but today’s mission is strictly personal. You flew from your home near Chicago (DPA) to Rochester, Minnesota (RST), to visit your father, who is recovering after major surgery. He’s doing great, and through the magic of general aviation you can get home the same day. The 240 nm flight should take just under 1.5 hours in the speedy Cirrus.

That is, if the weather cooperates. Check the weather brief below and tell us what you would do. Your proposed departure time is 1830 Zulu.

Overview

The map view on ForeFlight doesn’t look like a slam dunk, but it also doesn’t look impossible. A line of storms is just north of Rochester, but it appears to be moving to the north (and away from your route).

The driver of this system is a low pressure system just to the southwest of Rochester, with a warm front stretching out to the east.

Radar/Satellite

The regional radar picture shows that line of storms to the north, with some large sections of red. You’re in the gap right now, and to the south it appears to be mostly green.

The infrared satellite image shows thick clouds to the north and west of the departure airport, but with clear skies closer to Chicago.

Forecast Charts

Where is that system headed? The prog charts show the low moving east and dissipating somewhat. But rain is forecast throughout the area over the next 24 hours.

Text Weather

The weather at RST shows thunderstorms, but the ceiling and visibility are both pretty good. The forecast calls for VFR conditions, with temporary reductions in ceiling and visibility as thunderstorms move through.

Weather en route is VFR, with 10 miles of visibility everywhere and fairly high ceilings.

Weather at your destination is excellent, although the forecast calls for scattered storms later in the day (after your arrival).

AIRMETs

A quick of the AIRMETs shows potential turbulence below 7000 feet through southern Minnesota and Wisconsin.

There are no AIRMETs for IFR conditions nearby.

Finally, your route looks ice-free.

This makes sense when you look at the freezing level, which is pretty high for late spring.

Convection

With VFR conditions and no major threat for icing, your attention turns to convection. This is certainly going to be an issue today, with that low pressure system driving a line of storms. The radar tracks show it moving northeast right now, and the convective outlook shows potential storms marching through Wisconsin and northern Illinois over the next eight hours.

Decision Time

It’s time to make your decision: are you headed for the airplane or for a hotel? There are storms in the area, so there’s reason to be cautious. Then again, it looks like there’s a nice gap where you could escape. Add your comment below and tell us what you would do.

Bonus question: if you decide to go, would you do this IFR, VFR or either?

40 Comments

  • Go to the airport.

    The only apparent risk is right at the start of the flight, so I’ll know then if the weather has cleared the airport to the north, and the SE sector is clear. (If the weather were near my destination, it would be a different calculation, because things could change while I was enroute.)

    Assuming all is well at the airport, I’d plan a big dog leg to the south to keep me further behind the squall line (I’m in a fast plane, after all), and fly VFR. If I can’t stay visual in what’s supposed to be a clear area, then the forecasts are way off, it’s be time to land and reset.

  • No problem at all. You are going to almost certain better weather.

    Reverse route, trying to get “into” that area? that would be more of a problem in my experience.

  • I agree with everything that David Megginson said. I’ll just add that bases at 3500 AGL and a high freezing level really add a lot of security. I’d go VFR with flight following at about 2500 AGL for fuss free dodging of the potential storms and rapid diversion capability, and if it went IMC I’d at least not have to worry about ice while picking up a clearance.
    The freezing level isn’t a primary consideration, just a nice step away from the reaper if things go wrong.

  • I would have to say go to the airport and re-evaluate the conditions. I have enough experience to say that the edge of lines that that can be hell on wheels. If you are IFR rated then I say go for it and if you have some form of weather in the cockpit be it ADS-B or SiriusXM or onboard weather radar. I will qualify that to say if you can launch in a reasonable time. You are setting up a race condition so if your going get going while the getting is good but be prepared to call for a pop up ifr if it hits the old fan in route. One thing not mentioned was the availability of IAPs at the destination and what the limits are. This also needs consideration. In a flight like this don’t launch unless you have a bail out plan. As stated a dog leg route might be an option but it’s probably better to push it to the firewall and go direct under IFR.

  • This is relatively straight forward. If the tops of the overcast are reasonably low (under 10-11k), then I’d file to get in between layers so it would be easy to see where the buildups are. If not, I agree with the others to head a bit more south VFR to get away from the line, then southeast toward Chicago.

    If this flight was going the other way, it would take on a completely different decision process.

  • It’s a go for me. The key for me is the high ceilings. I live in the southeast and spend lots of time with Thunderstorms and I can say if I see high ceilings along my route I know that I will most likely be clear of clouds and can easily navigate around the storms. I would go IFR and I would not be shy about my desire to remain clear of clouds because it is truly the only way to avoid the serious weather.

  • For me personally it’s a no go. Not enough experience flying in less than southwestern sunshine. I’ll wait it out. However seeing T storms in the forecast, most likely would’ve drove there or taken the airlines if I really had to be there which sounds like this is the case.

  • One of my favorite tools is an animated weather radar display. It enables a good look at the dynamics of the situation. If it showed the primary line moving away and no pop-ups behind it, I would probably make the decision to go. I would file IFR – it is cheap insurance and this is not a pleasure/sightseeing flight.

  • It is a go. Weather looks good. I do all XC flights IFR and I’ve got NEXRAD on two devices- Foreflght and an older G396 handheld on the yoke. I would expect some IMC along the back side of the line of weather but could climb above or not. Depends on area forecast where tops are as well as asking ATC- they’ll know or will ask other pilots. I would not expect much turbulence so this is a pretty routine flight for me.

  • I’ve done this. Very similar situation coming back from Dayton/Air Museum. VFR and behind the front, snaking ahead of smaller cells behind it. With radar on board and ATC Flight Following, I had no issues navigating between the IMC. Knowing the speed of the front and keeping an arc path behind it to maintain a consistent distance behind it was no issue. You can do that in the spring here, but during the winter, expect low ceilings and no VFR gaps on the backsides.

  • I haven’t a clue. All of my meager flight time is in sunny S. Texas. I’m only writing to see if there IS a correct answer. All the posts seemed reasonable.

    • It depends on one’s experience and level of comfort of the pilot and passengers. For one thing, there are airports all along the way so easy to make a decision to divert if necessary. But, experience in flying in this type of situation, partly because I’m from the Great Lakes area, told me quickly that it would be a “go” for me with probably some IMC but generally an uneventful flight. The weather of concern is NE of the path and moving NE.

  • This could be my inexperience and few flight hours, however, I would err on the side of caution. For a more experienced pilot this weather may look benign. For me, especially living in an area where thunderstorms can build so rapidly, I would go back to the hotel, have a nice dinner, get a good night’s sleep, and arrive safely at home mid-morning the next day.

  • I’d go but be aware of the movement of everything to the northeast. I’d almost ignore the line moving away from the route.
    However! The area southwest of the route isn’t clear, there’s moisture and the cells with lightning show there’s energy there too. The convective forecast maps show this too.
    What time of year is this? There’s still plenty of time for the sun’s energy to blow this area to the Southwest of the route up.
    Animate the radar but also be aware that areas of weather blow up and die down dynamically as well.
    Go, see dad, but be ready to hangar and stay the night IF that area blows up later.

  • Oops. Just saw that you are already in RST. Was thinking this was a round trip from DPA.
    That would be a good exercise though. Can you go, spend time and get back before the area south of course closes in? Or doesn’t?
    Good scenario John!

  • Go. IFR although possible to try VFR and file in the air, but why? Risk assessment should include recent experience in IFR and Icing. Personal stress and tiredness needs to be considered.

  • I would go. File IFR, there is plenty of area between the cells, wx to the southwest is light to moderate and would be a bumpy ride and the embedded areas of extreme are easily avoided.
    If not able to go IFR. Stay low and have a plan to divert and spend the night.

  • Go, IFR, to make maximum use of the help ATC can provide. Agree that may be smart to vector south a bit initially,especially to avoid turbulence, but then flight should be good.

  • Go back to Mom and Dad’s place and spend some more time with them. Help Dad with stuff around the house. I imagine he’d need it after major surgery. Wait out the convective activity.

  • Is this a trick question. It’s a Cirrus so you always launch. If things go bad you pull the magic red handle and land softly in a hay field.

  • It’s a go for me.!! C-185, NEXRAD on board with two backups. IFR for sure. Wouldn’t do this one after dark though.

  • Likely getting my PPL in the next month or so. Without a doubt no-go for me. I don’t like the low spinning weather from the southwest towards me. It looks clear in that narrow wedge, but I would not want to be in the air if a storm popped up coming towards me with the north east having weather to sandwich me. You all are much more experienced than I and so it’s my lack of experience as much as anything. And I’m known as a “chicken; )”

  • I would definitely file an IFR flight plan (a route that would take me south of the direct line from departing to destination airport) and check the weather again when I arrive to the airport. This is really based on comfort level in this kind of weather, but I think this could be a non-event flight.

  • Used to fly 135 charter in twin Cessnas and 90 Kingairs. I would think long and hard about going into clouds that potentially have thunderstorms imbedded in them. If I had high bases and could safely go under and stay visual I would.
    Even with radar and now XM its always preferable to see and avoid weather.

  • Go before next weather gets close to departure.

    This would be an easy day compared to routine summertime dodging tstms on the east coast. I prefer VFR and daytime only when dealing with storms. VFR allows me to control my routing destiny and stay under cloud bases so I can see what I’m dealing with (rainshafts, light vs dark clouds/lightening). I always make sure I have an out either behind me or clear to one side. Use inflight weather only to confirm that there aren’t surprises lurking behind what you can see and that there isn’t widespread IMC developing. Watch out for how late in the day you depart as post-storm can be an issue with temp/dew points merging (scud/fog) and ceilings/vis dropping as sunset approaches. Don’t trust ATC not to put you in a cell on IFR routing or to give you a clear altitude…see VFR comment.

    If you don’t like what’s developing, land, refuel, replan or stay on deck until the weather is what you need (an FBO couch is better than a dirt nap)…as they say, the mishap investigation is usually on a nice sunny day. Don’t forget the airplane can fly in any direction (not just towards the destination) and refilled tanks=more options.

    If you aren’t confident in your experience/aircraft vs current conditions, airline, drive or wait for a better day.

  • It looks like the flight path is right along the front line, not an easy thing to predict where the convection will pop up. This is an IFR flight for sure unless you have real time weather onboard you will need ATC to help you avoid developing cells. As to launching VFR and staying below the cloud deck, better hope you have time to alter course and find another airport before the cloud deck or cells closes in. I’m not big on hope and I never have any luck.

    • If going IFR thru an area of CBs, my suggestion would be to wait for better weather if you have to rely on ATC to avoid weather. ATC may be busy with other folks or other perceived higher priorities than your personal weather avoidance, and they may not understand why weather is more critical to a GA airplane than a higher wing loaded or beefier airliner/mil acft…Scott Crossfield comes to mind. In busy airspace it is a gamble to assume they have the time to manage your flight weather (or won’t miss something when handling someone else), even with the best of intentions on both sides.

      Regardless, don’t let cells get between you and your out (either vertically or horizontally).

      Completely agree IFR for low ceilings/stable weather.

  • Everyone of you guys have what if solutions with most of you going IFR. Ok, just remember this guy is on his own time and he is with his Dad who just had major surgery. You don’t think his mind will be on his father’s recovery as he “hurries to beat the weather”. Why not let the storm blow through while your on the ground with your Dad. Tomorrow is an easy answer for me. Weather is a subtle seductress. Why not be with family overnight. PS. A lot of pilots who tempted the weather were buried on beautiful days.

    • Excellent point Denny. Everyone should look at Richard Rockefeller’s accident. A highly qualified pilot in an extremely capable aircraft departing from one of the best airports in the country after his fathers 100th birthday party. He didn’t get very far.

  • Do a last minute check before departing and go VFR (daylight). Stay underneath, using flight following (easier transition to IFR if necessary) and your on-board weather devices. Have plenty fuel if a diversion becomes necessary.

    But ALWAYS REMEMBER, if everything goes to hell in a hand basket, it beats spending your 5 last years in a nursing home with pureed peas running down your chin.

  • Flying doesn’t have to be risky – we only make it risky with our decisions to fly in WX that is marginal – like this. I am largely surprised at the responses of my colleagues on this one. The issue here is the WX at the departure airport. Whether or not it’s clear much of the flight with no ice and moderate ceilings/vis is moot. Is there a gap in the line of showers and precip? Sure! Can it be done? Sure! But why raise the risk. In my humble opinion, I think it’s unwise to depart into an area that has TS in the vicinity of the airport. These TS can produce WS and other highly undesirable events which are truly dangerous to GA flight. Without on-board radar, it is folly to launch into the face of this as I want 1 mile of lateral distance for every 1,000 feet of tops – not just in the ones that recently passed to the NE but in the ones coming from the SW as well. Given their location, this is already compromised. Dated, on board NEXRAD is not weather avoidance equipment! In addition to significant turbs and WS with the amount of moisture and where the freezing level is at, I would consider the possibility of hail as a viable risk as well for the first 20 miles – though none has been reported. I feel quality, reliable, safe flying starts with good decision making. I think it was Frank Borman that said, “a superior pilot is one that uses his/her superior judgement to avoid situations that require his/her superior skills. Additionally, staying low beneath the OVC and watching for the build-ups is called “scud running”. We paid for an IFR aircraft and obtained an IFR certification for a reason, and this is that reason – not to fly in situations that require scud running.
    No, I would call the FBO to make certain my aircraft was inside for the next 2 hours and recalculate.

    • You call scattered at 3500 agl scud running? How do you ever fly? Without the storms that’s a typical day with thermal generated CU.

    • IMHO, experience and comfort level have a lot to do with it. As I wrote earlier, I’d be perfectly comfortable taking off with a south vector before continuing southeast, after considering all weather conditions, including wind shear and available PIREPS. If you are not comfortable, don’t go, just don’t be so self-righteous with the rest of us!

    • Not sure where you live, Roger, but “marginal” has a lot to do with what you’re experienced with. I live near the Great Lakes, so I’m very used to the kind of weather in this scenario—as others have mentioned, if you’re not willing to fly with a front within 50 nm, then you’re probably not going to fly, period, around here.

      On the other hand, I’d probably be much-more timid about flying in the 30-40 knot surface winds of Prairies, and my hesitation about flying under a reasonably-high ceiling through passes and valleys would probably puzzle pilots in mountain states.

      I find this scenario easy, because (unlike with much of my flying) all the answers are clear right at the start: after I get to the airport and preflight, I’ll know with reasonable certainty what the surrounding weather’s going to be like for the next 20-30 minutes, and that’s all I need to get to the better weather to the southeast, followed by an easy flight into improving conditions to the destination, with safe diversion airports every few miles along the way.

      If the weather were closing in on my destination instead of moving away from my point of departure — or if the weather along the way were marginal (remember from my earlier comment that I’d plan a dogleg to the south so that I wasn’t right behind the front) — it would be an entirely-different calculation.

  • PS – if onboard “dated” NEXRAD radar (5 min updates) is not for weather avoidance, then exactly what is it for? That’s what I use it for. I don’t cozy right up to cells using NEXRAD, but it sure helps my SA and allows me to plan better routing for cell avoidance. Coupled with what ATC is seeing and getting from other pilots, it’s a great tool.

  • Phil, sorry I was not trying to be self-righteous. I should have said “for me” it would have been the wrong call as I thought it better to let it pass.

    With respect to NEXRAD, I agree with you it’s great for SA and the like and a wonderful tool, understanding the movement, etc. however, 5 minute updates from Sirius does not relate to when their downloads were obtained. Much study has gone into this and even with 5 minute updates, some of that WX information may be 30 minutes old or even more dated. That is the reason I suggested if flying embedded, one should have on-board radar to discern real cell position.

  • I would go based on the info I have but, would file IFR just in case conditions deteriorate enroute. I would also look for airports along the route in case I needed to make an unplanned stop.

  • 1. Go to the airport and look around
    2. If reasonable VFR, head first for Dubuque – lots of en route airports if forecast falls apart.
    3. File a popup IFR if needed and capable, but easier to dodge cells VFR if reasonable ceiling.

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