Tag: Go or No Go

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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Go or No Go: summertime in Florida

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Summer in Florida means thunderstorms, but often the cells are widely scattered and easy to avoid. Will that be the case today? The mission is to fly your Cessna 172 from Orlando Sanford Airport (SFB) up the east coast of Florida, landing at Saint Simons Island (SSI). It should take about 1:15, and while you’ll be able to monitor the weather with your iPad and ADS-B receiver, the flight will be VFR since you are not instrument rated.

ETD is 1700 local, 2100 Zulu. Read the weather briefing below, then add a comment and tell us if you would take off or cancel.

Overview

The map on ForeFlight is quite colorful, as you would expect for a summer afternoon in Florida. It looks like scattered rain and thunderstorms are all over the state, with the worst to the south and west of your route.

SFB route - Go or No Go: summertime in Florida

The surface analysis shows the big picture—what’s driving the radar image. The short answer is, “not much.” There’s clearly some instability in the atmosphere, but there are no significant fronts or low pressure systems in the area.

Surface analysis - Go or No Go: summertime in Florida

As you would expect from the radar image, there are plenty of Convective SIGMETs around.

Convective SIGMETs - Go or No Go: summertime in Florida

Radar and Satellite

For a more detailed look at the rain and thunderstorms, you pull up the static radar image in ForeFlight, which shows the composite radar image for Florida.

GNG radar static - Go or No Go: summertime in Florida

There’s a lot of rain over the state of Florida, but much of it in your area looks to be green. This could be a case of high level moisture that doesn’t reach the ground, so you look at the lowest tilt radar image in ForeFlight. Sure enough, it removes a lot of that lighter green, although the storms up by Tallahassee look serious.

Base reflectivity - Go or No Go: summertime in Florida

A satellite image is another great tool for determining how serious any rain or storms might be. First, a look at the infrared image shows lots of cloud cover, over almost the entire route of flight. Much of this looks quite thick.

IR satellite - Go or No Go: summertime in Florida

Just as you compared base and composite reflectivity, it’s a good idea to compare infrared and visible satellite images. The visible image shows lots of clouds, but in the eastern part of Florida a lot of those clouds look to be higher level ones—maybe some wispy clouds blown off the top of the bigger storms.

visible satellite - Go or No Go: summertime in Florida

Text Weather

Since you’re VFR today, it’s not enough to consider the potential for storms. Can you stay out of clouds along your route? The good news is that your destination is reporting good VFR conditions, although the TAF shows scattered storms and the METAR has a “LTG DSNT W” note.

SFB weather - Go or No Go: summertime in Florida

En route weather looks good, with two airports along the coast reporting clear skies.

en route GNG weather - Go or No Go: summertime in Florida

Your destination is also showing excellent weather, with some gusty winds and the chance for some rain showers.

SSI weather - Go or No Go: summertime in Florida

Decision Time

It’s time to make the call: ? In some ways, this is just a typical summer day in Florida, so dodging an occasional build-up shouldn’t be too hard—the weather is VFR at your departure, en route, and at your destination. But there are plenty of storms around, and some of them look pretty nasty. Plus, your departure and destination both suggest the chance for rain and/or storms.

Add a comment below and tell us what you would do.

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Go or No Go: ice and storms over Montana

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Today is one of those “in between” days, which are frustratingly common in flying. The weather isn’t great, with some rain and potential in-flight icing, but it’s not terrible either, and you fly a well-equipped airplane. The proposed mission today is to fly from your home in Bismarck, North Dakota, to Billings, Montana, the first leg on a five-day tour of the Western United States in support of your business. Your Piper Turbo Aztec is well equipped for IFR missions in the West, with a cruise speed over 200 knots, built-in oxygen, and deice boots. The flight should take just under two hours—if you can go.

Planned departure time is 2030Z. Read the weather briefing below, then add a comment and tell us what you would do. ?

Overview

The map in ForeFlight shows no major lines of weather, but there’s definitely some rain over eastern Montana, right along your route.

GNGNDoverview - Go or No Go: ice and storms over Montana

Looking at the surface analysis, there are no major fronts in the area, but it seems like there’s some type of minor disturbance.

GNG surf analy - Go or No Go: ice and storms over Montana

The prog charts show some rain and storms developing over the next 24 hours, slowing moving east.

GNGBIS prog 1 - Go or No Go: ice and storms over Montana

Radar and satellite

Job one is to understand whether that rain is just rain or something more serious. The regional radar image shows a very scattered area of cells, but some of them do look to be convective.

GNGBIS radar - Go or No Go: ice and storms over Montana

The infrared satellite backs up that theory, showing some clouds with vertical development.

GNGBIS ir sat - Go or No Go: ice and storms over Montana

Finally, a look at the visible satellite suggests there might be a path through the build-ups in North Dakota, but probably not once you get into Montana.

GNGBIS vis sat - Go or No Go: ice and storms over Montana

There is a convective SIGMET outlook in the area, but the actual SIGMETs are well north and south of your route.

GNGBIS SIGMET - Go or No Go: ice and storms over Montana

Icing

In addition to concerns about thunderstorms, it looks like in-flight icing is likely. A look at the freezing level chart shows you’ll almost certainly be flying below 0 degrees at a typical cruise altitude of 10-16,000 feet.

GNGBIS freezing level - Go or No Go: ice and storms over Montana

Icing forecast charts show a good chance of ice, starting at about 9000 feet.

GNGBIS ice 9k - Go or No Go: ice and storms over Montana

The threat of icing seems to be fairly consistent up into the teens today. You might get above it by 22,000 ft, but that’s a lot higher than you like to fly.

GNGBIS ice 15k - Go or No Go: ice and storms over Montana

The AIRMET for icing backs up this forecast, with moderate ice predicted over much of your route.

GNGBIS AIRMET ice - Go or No Go: ice and storms over Montana

The cloud forecast map shows fairly high bases, but tops are above FL250 in eastern Montana.

GNGBIS clouds - Go or No Go: ice and storms over Montana

Text weather

Finally, some good news. The weather at your departure airport is good VFR and is forecast to stay that way.

GNGBIS - Go or No Go: ice and storms over Montana

En route weather reports are showing good VFR, with that fairly high ceiling.

GNG en route - Go or No Go: ice and storms over Montana

Your destination is also reporting good VFR, and the TAF looks favorable.

GNGBIL - Go or No Go: ice and storms over Montana

Decision time

It’s time to make the decision. The weather at your departure and destination is quite good, and you fly a very capable airplane. But there is definitely some work to do en route if you decide to launch, including possible icing and thunderstorms. You could try to go low, and stay out of the clouds, or you could try to go high and get on top of the ice. Then again, you could cancel and play it safe.

What would you do? Add a comment below.

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Go or no go: how bad is the turbulence?

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Over the last 10 years, you’ve gotten to know your Mooney 201 quite well, using it to travel around the central United States at 160 knots. You’re hoping to do that again today, on a flight from your home in Wichita, Kansas (ICT), to Amarillo, Texas (AMA). Your airplane may be vintage, but it’s a fine cross-country cruiser, so the trip should take just over an hour and a half.

Proposed departure is 1400Z and you’re hoping to go VFR if possible. Read the weather reports below and tell us if it’s a go or a no go for you.

Overview

At first glance, conditions look reasonably good for your flight, with green METAR circles all over the map. But some green radar returns are worth looking at in more detail.

GNG route ICT - Go or no go: how bad is the turbulence?

The current surface analysis shows benign conditions in Kansas, but a weak front over North Texas.

GNG surf anal - Go or no go: how bad is the turbulence?

The first prog chart shows storms developing over Oklahoma later in the day.

GNG prog 1 - Go or no go: how bad is the turbulence?

The short term convective forecast matches this chart, but all the activity should be east of your route.

GNG convective - Go or no go: how bad is the turbulence?

Radar and satellite

There’s definitely some rain along your route, but all the green METAR circles suggest it isn’t too serious. To learn more, you turn on the “lowest tilt” radar layer in ForeFlight. It shows no green along your route, suggesting that area of precipitation is aloft and not hitting the ground. Maybe it’s just wet clouds above 10,000 feet?

GNG radar 2 - Go or no go: how bad is the turbulence?

The visible satellite image shows fairly consistent clouds across Oklahoma and southern Kansas.

GNG visible satellite - Go or no go: how bad is the turbulence?

But the cloud forecast shows this to be a fairly high layer, with bases above 10,000 feet. It looks like you could fly along at 6,500 or 8,500 feet and be in the clear.

GNG clouds - Go or no go: how bad is the turbulence?

Text weather

This part is pretty easy: your departure airport is reporting excellent VFR conditions and it is forecast to stay that way.

GNG ICT weather - Go or no go: how bad is the turbulence?

Your destination is likewise forecast to remain VFR throughout the day. The wind is blowing, but when is it not in Texas?

GNG AMA weather - Go or no go: how bad is the turbulence?

Turbulence

The weather is good VFR and that rain appears to be up high. But those PIREP symbols on the map are worrying. There are multiple reports of moderate turbulence at lower altitudes, and some are even severe. These are west of your route, but not by too much.

GNG PIREP 1 - Go or no go: how bad is the turbulence?

Another one, closer to your route, shows moderate turbulence at 5,500.

GNG PIREP 2 - Go or no go: how bad is the turbulence?

South of your route there’s another one, with some worrying notes.

GNG PIREP 3 - Go or no go: how bad is the turbulence?

The turbulence forecast layer in ForeFlight shows a few areas of concern, but nothing major.

GNG turb 5k - Go or no go: how bad is the turbulence?

The current SIGMET map might offer an explanation. The gusty winds seem to be causing low level wind shear, although again it’s mostly east of your route.

GNG SIGMET - Go or no go: how bad is the turbulence?

Decision time

It’s time to make the call. The weather is great, but the wind is blowing and it might be a bumpy flight. Are you flying to Amarillo or canceling? Add your comment below and tell us your decision.

Go or No Go: home before the rain?

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A relaxing few days in the Florida Keys have come to an end, and you have Mother Nature to thank for your amended plans. An imposing cold front means that, instead of staying on the beach, you’re trying to get home before storms and IFR conditions come to town. The goal today is to fly your club’s Cessna 172 from Marathon (MTH) to Orlando (ORL), Florida. It should take about two hours, and with a proposed departure time of 4:15pm, you would be landing a little before sunset.

But the weather you see on ForeFlight isn’t exactly quiet. Since you do not have an instrument rating, this flight will have to be made VFR. Can you get to Orlando safely? Review the weather below and add your comment.

Overview

The route overview makes it clear what the challenge will be: getting home before the rain moves in. It appears quite scattered around Orlando, but there are some uglier colors up north.

The surface analysis shows the source of this rain, with a cold front draped across Florida from west to east.

The prog charts show the front, along with its associated rain, sagging south overnight.

Tomorrow morning looks even worse, so spending the night may not solve any problems. But maybe the worst would move off to the east?

Radar and satellite

To get more detail on the rain, you pull up the regional radar image for Florida. It shows a convective cell right over Orlando, but the solid line of rain is still north of Ocala.

The satellite image shows mostly clear skies for the first half of your flight, but increasing clouds the further north you get.

The cloud forecast map suggests that ceilings will only become an issue right around your destination.

Text weather

The weather in the Keys is excellent, and forecast to stay that way (that’s why you came in the first place!).

En route, most airports are reporting scattered clouds at around 5,000 feet, but good visibility and light winds.

In Orlando, the current weather is great, but the TAF shows marginal VFR conditions as the day goes on.

There’s one Pilot Report that is worth considering – an Airbus just a few miles north of your destination airport reported a broken ceiling at 2,700 feet.

Decision time

It’s time to make the call: are you taking off for home or spending another night in Marathon? The weather looks quite good until the last 20 miles, but those miles include scattered rain and perhaps marginal VFR ceilings. Is it a go or a no go? Add your comment below.

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?

Go or No Go: above or below the clouds?

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You earned your instrument rating years ago, but you haven’t been current in a long time. Now you’re kicking yourself for that lapse in currency, because your VFR-only limitation is going to make an easy IFR flight a marginal VFR flight. You’re hoping to fly your 1972 Cessna 182 from your home in Middletown, Ohio (MWO), to Marion, Illinois (MWA). That flight should take just under two hours, but while the weather is great at your home airport and it seems to be good at your destination, in between isn’t as promising.

Proposed departure time is 3pm eastern (1900Z). Read the weather briefing below and tell us what you would do: go or no go?

Overview

The Maps page in ForeFlight shows a pretty calm weather picture, but the satellite layer suggests there might be some clouds to deal with.

The surface analysis shows a similarly calm picture, with a weak warm front running parallel to the Mississippi River.

The prog charts show no significant weather developing tonight.

Radar and satellite

The radar part is easy: there are hardly any returns anywhere in the central United States.

The satellite imagery is a little more complicated, especially for a VFR pilot. Your home airport is in a hole, but a thin layer of clouds seems to be sitting along your route.

The infrared satellite suggests it is indeed a shallow layer, so flying VFR over the top might even be an option.

Winds and clouds

The cloud forecast chart adds more details to the ceiling question. It looks like the layer starts at about 3000-3500 feet and the tops are at 5000 feet through southern Indiana. But remember, this is a forecast.

The winds aloft forecast at 6000 feet adds a little more detail—at least you won’t have much of a headwind.

Text weather

Your departure airport is showing severe clear, but is forecast to become marginal VFR overnight.

En route, a consistent ceiling seems to be hovering around 2500 or 3000 feet, but with good visibility and light winds underneath.

Your destination is showing good VFR conditions and is forecast to stay that way.

There’s one PIREP that might be helpful. Just south of your route, a regional jet reported bases at 3900 feet MSL and tops at 4700 feet.

Decision time

The weather definitely isn’t “bad,” but there are just enough clouds to make you think here. Do you launch and stay under the clouds, confident that you have good visibility and no rain? Do you climb up above the clouds and enjoy the sun, confident that your destination is clear? Or do you cancel, worried that this might turn into a scud run in the fading light of a December day?

Add your comment below.

Go or No Go: above the bumps, below the ice?

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Fall in Maine is simply wonderful, as you’ve seen for yourself this week. The air was crisp and the colors on the trees were beautiful, but now it’s time to fly home. Your Cessna 310 is fueled up and ready to make the 3.5 hour flight from Bar Harbor (BHB) to your home near Gaithersburg, Maryland (GAI). Will the weather cooperate?

You’re instrument rated and current, so you’ll be flying this trip IFR unless there’s a good reason not to. Your airplane is well equipped, with datalink weather, dual WAAS GPSs, and a good autopilot. You do not have deice equipment. Read the weather briefing below, then add a comment to tell us whether it’s a go for you, or a no go. Proposed departure time is 1930Z.

Overview

The Maps page in ForeFlight shows a fairly colorful picture, with rain and some convective activity in the Northeast, plus plenty of PIREPs.

The surface analysis shows a cold front moving in from the west, which is driving a lot of the activity from a weather standpoint.

The forecast charts show the front moving through New England overnight, with accompanying rain. The 12-hour chart is really showing current conditions:

The 24-hour chart shows the front’s position tonight.

Radar and satellite

You know you’re dealing with an advancing cold front, so step one is to get a feel for the clouds and precipitation. The regional radar shows an area of light to moderate rain in Massachusetts, New Hampshire, and Maine, plus some heavier returns over New York.

The infrared satellite shows plenty of clouds over the first two thirds of your route today, with the thickest part in Maine.

The visible satellite offers some additional detail.

Hazards: ice, turbulence, convection

It looks like convection, icing, and turbulence are all potential issues today. That means a look at AIRMETs and SIGMETs is in order. There are no SIGMETs, but there is a convective SIGMET around that line in New York.

The AIRMET for turbulence is a busy map, which is to be expected given the windy conditions ahead of that cold front.

The winds aloft chart for 6000 feet explains the busy map—winds are out of the west at 50 knots over New York.

The Pilot Report (PIREP) map shows plenty of orange icons. It looks like a bumpy day in the clouds and also down low with the gusty winds.

Looking a little closer at some PIREPS shows somewhat conflicting details. A Cirrus just north of your route at 8000 reported above freezing temperatures and no turbulence; a Cessna 402 just south of your route reported light to moderate turbulence and light snow, but in clear air at 8000.

Icing is another concern, given the time of year and the location. It looks like icing is only an issue at higher altitudes today.

Checking the freezing level confirms this. You should be above freezing as long as you stay below about 8-9000 feet.

Icing PIREPs mostly support this picture—there are plenty of them, but all above 10,000 feet.

Surface weather

While you’re IFR today, it’s worth checking out the overall cloud picture. The 3-hour forecast chart shows widespread clouds until you get to Maryland, but some of the ceilings are fairly high.

Your departure airport is reporting marginal VFR conditions and reasonably strong wind from the south. The forecast calls for rain and thunderstorms to move in after your departure time.

En route, most airports are reporting solid VFR conditions with a ceiling around 7000 feet AGL.

Your destination is reporting good VFR and is forecast to stay that way, but the wind is definitely blowing.

Decision time

It’s time to make the go/no-go call. All the METARs show VFR or at worst marginal VFR conditions, and there appears to be no threat of icing as long as you stay below 10,000 feet. In fact, you may be in VMC for most of the flight if you cruise at 6000 feet. However, thunderstorms are firing up in a solid line over New York, and the strong winds both aloft and at the surface promise a bumpy ride.

Add a comment below and tell us what you would do.

Go or No Go: smoky San Carlos

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The overall weather for your flight today from Scottsdale, Arizona (SDL), to San Carlos, California (SQL), looks excellent—no fronts, no storms, no ice, hardly any clouds—with one exception. Huge wildfires have covered much of Northern California with smoke. That means widespread IFR conditions near your destination. Can you make the trip?

The flight should take about 3:30 in your Cirrus SR22, given the less-than-direct route and 12,000 ft. cruising altitude that are required for avoiding terrain. That’s a long trip in this airplane, but certainly within its capabilities; you should arrive in the Bay Area with about 20 gallons of fuel remaining, which is more than your one hour personal minimum. However, the need to fly to an alternate might cut into that reserve. You’re instrument rated and current.

Departure time is planned for 9:00am PDT (1600Z). Read the weather briefing below and then add a comment sharing your decision.

Overview

Your trip today will take you north out of the Phoenix area, then west towards Bakersfield, before turning northwest towards the San Francisco area.

The surface analysis shows hardly anything to worry about, with no organized weather system throughout the Southwest.

The prog chart shows more of the same, with generally fair weather continuing throughout the day and into tomorrow.

Satellite

There’s nothing to look at on the radar today, but the satellite image shows the smoke covering much of California. It’s clearly not vertically developed, but it is all over the coast.

Graphical Forecasts

The Graphical AIRMET shows what you would expect—good weather except for restricted visibilities. The unusual FU stands for smoke.

These weather conditions are where the Graphical Forecast for Aviation (GFA) can add some detail. First, the surface forecast, which shows widespread low visibility near your destination.

Then there’s the cloud forecast, valid for about an hour and a half before your arrival. It shows clear skies except along the coast, where tops are low and ceilings are forecast to be around 1000 ft.

Text weather

Here’s where the rubber meets the road. Will conditions allow you to make a safe approach and landing at San Carlos? First the good news: your departure airport is reporting excellent conditions and it’s forecast to stay that way.

En route, the weather is good VFR until you get north of Los Angeles. At your destination, conditions are definitely IFR—in fact, they are below approach minimums right now (which are 900 and 1 1/4 for the RNAV (GPS) Z to runway 30). The nearest TAF (for SFO) suggests things will get better as the day goes on.

Given the current weather at SQL, the TAF at SFO, and common sense, you need an IFR alternate today. Unfortunately, there aren’t many good options. Smoke has brought ceilings and visibility down all over California. Here are three nearby international airports, all reporting conditions that are above approach minimums, but not by much.

The story is the same almost everywhere within 100 miles. In fact, Bakersfield is the nearest airport with truly VFR weather right now (clear skies and 3 miles visibility with haze), but that’s 200 miles away.

A few PIREPs offer the last details. As expected, tops are very low but so are ceilings.

Decision time

For a fairly benign weather day, there’s actually a lot going on here. First things first: if the TAF holds, you can fly to your destination and land safely. Easy. Legally, you need an alternate and while none of the airports around San Carlos qualify right now based on the METARs, they do based on the TAFs. In fact, you could wait half an hour longer and eliminate the need for an alternate altogether. The only minor issue is that a Presidential TFR is going active early in the afternoon in Phoenix, so you’d definitely like to be airborne in the next two hours or so.

The legwork for a “legal” IFR alternate is beside the point, really. When you arrive at SQL, you’ll have enough fuel to shoot the approach, miss, and divert to a nearby airport (there are plenty around with precision approaches, including SFO, OAK, SJC). Given all that, you’ll still have the FAA-mandated 45 minutes of fuel on board, so you’re legal. But you won’t have much more fuel than that, so if conditions happen to go down, you have few good options and no solid VFR weather within range. And then of course there’s the hassle factor—San Carlos is much more convenient for your ultimate destination than the big airports at San Jose or San Francisco, not to mention the higher costs.

Is it a go or a no-go? Add your comment below.

Go or No Go: another summer day in the Southeast

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Another summer afternoon, another radar splattered with red and yellow cells. After many years of flying in the Southeast, you’re used to this picture but that doesn’t mean you ignore it—thunderstorms are a serious threat for any airplane. The goal today is to fly from Sarasota, Florida, to Atlanta, Georgia, in your Cirrus SR22. Will the weather allow it?

The trip should take about 2:15, and your Cirrus is certainly well equipped, with a Garmin G1000 glass cockpit, SiriusXM datalink weather, TKS deice system, and a good autopilot. Proposed departure time is 2130Z (5:30pm local). Read the weather report below, then add a comment and tell us whether it’s a go or a no-go for you.

Overview

The radar image in ForeFlight shows plenty of rain and thunderstorms, both in eastern Florida and in a large area over Alabama and the Florida Panhandle.

The surface analysis is pretty quiet in the region, with no major fronts or low pressure systems.

Forecasts

The prognostic charts suggest conditions won’t change much over the next 36 hours. The 00Z chart shows widespread showers and storms, although mostly the lighter green “Chance” markings.

Tomorrow morning shows a gap in the rain in Georgia, but it’s still an active map in Florida and Alabama.

There are no AIRMETs for turbulence or IFR conditions in the area, and the freezing level today is above 15,000 so icing is not a concern.

However, there are plenty of convective SIGMETs along your route.

Radar

As usual in the summertime, thunderstorms are the major threat today. That means it’s time to review the radar image in more detail. Start with the regional NEXRAD view.

Next, it’s worth exploring the ForeFlight radar image in more detail. In particular, the area in north Florida appears to show a gap, but it’s not a guarantee.

Closer to your departure, it looks like the worst weather has moved off to the southeast, but some lingering showers still show up.

This might be a day to compare composite radar reflectivity (above) with base reflectivity (below). This suggests most of the rain around Sarasota is not reaching the ground.

Satellite

This is probably a day where staying out of clouds as much as possible is a good idea. That means looking at the satellite imagery. Start with the infrared satellite layer in ForeFlight. As expected, this shows serious convection near Sarasota and west of your route, but relatively lower clouds in northern Florida.

The visible satellite images can give you a more detailed look at areas of building cumulus. Here’s the view of Florida.

And here’s the view further north.

One last tool that’s helpful is the cloud forecast chart. This shows that the tops in northern Florida will probably be above your airplane’s service ceiling.

Text weather

Finally, a look at departure and destination weather is always a good idea. Sarasota is reporting VFR conditions, but thunderstorms around. The notes show the lightning is east and southeast, suggesting the storms may be moving out.

Weather in Atlanta is excellent and forecast to stay that way, except for some potential CBs that are forecast to be gone by the time you arrive.

Decision time

It’s time to make the call. On the plus side, the weather at your departure and destination is good and forecast to stay that way. Your airplane is capable and well-equipped, there is a large break in the rain just east of your route, and you can complete the flight in daylight. On the minus side, there is a lot of convective weather around, including near your departure airport, and it’s a hot summer afternoon so things may continue to build. And of course you’re flying a piston airplane, so going to FL390 is not an option!

Are you flying the trip or canceling? Add a comment below.

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