Sudden High Wind not in any forecast

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JasonM

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JM
So last night around 10:30pm i'm laying in bed and hear the wind start instantly howling atleast 40mph and throwing stuff in my yard all over the place. I think, wth. I had just checked the wind forecast and they were to be calm to 4 kts. I looked at the TAF and the METAR for my local airport and it reported calm winds and forecast the same. Sky was clear, I think there was some storms a few hundred miles away.

My question is this. What would cause this and what can I be looking for to expect something like this. I thought maybe it was the front of the storm, but there wasn't anything anywhere close to me when I checked the radar maps.

Last question is why would the TAF not include the possibility of this?

I could only imagine landing at night and the AWOS/ATIS says calm wind, you don't notice any wind, you cant see the wind sock, then you get nailed with a 40+ crosswind from outer space.
 
Oh crap. Our UFO got sighted.

Weather is what it is, not what it was forecasted to be. You are never guaranteed that wind will behave as you expect.

Reading TAFs alone is not enough. Read the TAF discussions as well. Any discussion of "low confidence" means you don't have a clue what's going to happen. Even high confidence isn't a guarantee; it's just more likely to be right.

Forecasting the small scale stuff is very, very difficult. Especially how individual storm cells move.
 
Fly the airplane, not the forecast, or even the AWOS. If you detect wind shear, go around and reassess. At my field, it's customary for the AWOS to say one thing, the windsock something else, and still contradict with the other three airports less than 10 miles away.

As to the cause, it could be many things. Was there a frontal passage?
 
MAKG1 said:
Oh crap. Our UFO got sighted.

Weather is what it is, not what it was forecasted to be. You are never guaranteed that wind will behave as you expect.

Reading TAFs alone is not enough. Read the TAF discussions as well. Any discussion of "low confidence" means you don't have a clue what's going to happen. Even high confidence isn't a guarantee; it's just more likely to be right.

Forecasting the small scale stuff is very, very difficult. Especially how individual storm cells move.
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Where is a good place to read TAF discussions?


Brad Z said:
Fly the airplane, not the forecast, or even the AWOS. If you detect wind shear, go around and reassess. At my field, it's customary for the AWOS to say one thing, the windsock something else, and still contradict with the other three airports less than 10 miles away.

As to the cause, it could be many things. Was there a frontal passage?
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I get that. Fly the plane, but I am just trying to understand why something like this could sneek up on us. I have noticed that being very common for sure as for the AWOS to differ. I would think a 40+ gust could really screw you up if you were about to land on the ground and not be recoverable.
 
BTDT, had to go around multiple times, tried turning around (direct-x) and on what I told myself would be my last attempt before heading to an airport aligned with the wind made a rather beautiful landing with no one watching (passenger covered her eyes, figures right?)
 
JasonM said:
So last night around 10:30pm i'm laying in bed and hear the wind start instantly howling atleast 40mph and throwing stuff in my yard all over the place. I think, wth. I had just checked the wind forecast and they were to be calm to 4 kts. I looked at the TAF and the METAR for my local airport and it reported calm winds and forecast the same. Sky was clear, I think there was some storms a few hundred miles away.

My question is this. What would cause this and what can I be looking for to expect something like this. I thought maybe it was the front of the storm, but there wasn't anything anywhere close to me when I checked the radar maps.

Last question is why would the TAF not include the possibility of this?

I could only imagine landing at night and the AWOS/ATIS says calm wind, you don't notice any wind, you cant see the wind sock, then you get nailed with a 40+ crosswind from outer space.
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Do you live within five miles of the airport? The TAF is a pinpoint forecast and says nothing about what might happen outside of a five mile radius.

Bob Gardner
 
bobmrg said:
Do you live within five miles of the airport? The TAF is a pinpoint forecast and says nothing about what might happen outside of a five mile radius.

Bob Gardner
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6.74 miles, so not much further.
 
bobmrg said:
Do you live within five miles of the airport? The TAF is a pinpoint forecast and says nothing about what might happen outside of a five mile radius.

Bob Gardner
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It's not intended to say anything beyond a 5 sm radius, but weather is usually nearly continuous. Excepting things like front boundaries and squall lines. Terrain as well under some conditions.

It's a good bet that PAO weather will approximate TAFs at SFO, SJC and OAK, especially if they are all similar, as it's nearly in the center of all three, but more than 5 miles from any of them. There are some noticeable systematics, however. Weather at SFO is generally a little worse -- higher winds, lower ceilings, more clouds. And at SJC, it's a little better (no pesky bay or holes in the upwind mountains). But if all three say SKC, it's almost certainly a VFR day. Similarly, if all three say OVC005, stay home.

The truth is, no weather product is adequate for all phases of flight. Area forecasts are extremely rough, and that's all you have to deal with for the enroute phase. And you often can't get a METAR where you need it most -- mountain passes (even low ones), and an AIRMET Sierra for mountain obscuration or IFR conditions may or may not mean the pass is obscured.
 
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comanchepilot said:
thats not a TAF discussion - it is an area forecast discussion of the synoptic scale events impacting weather -
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True but they do use the TAF areas for the discussion, and occasionally include notes about what is included in TAF's for certain locations.

My area does that anyway... some weather forecasters don't have much to say in the discussions.

Example:

HAVE NOT EXPLICITLY
INCLUDED THUNDER IN THE TAFS GIVEN THE UNCERTAINTY OF THE MOST
LIKELY TIME FRAME BUT THE BEST CHANCE OF THUNDERSTORMS WILL BE IN
THE 03-09Z RANGE AT KINT/KGSO AND 06-12Z AT KRDU/KFAY/KRWI.
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scottd said:
If the surface observation didn't indicate any wind event, then the TAF was a good forecast if it also did not forecast such a wind event.
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if someone said the grass was green and the other person said the grass would be green, then they did a good job of saying the grass was green. :dunno:
 
ChrisK said:
I think it might have been a koan.
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what is a koan? :confused:

is it this? : a paradox to be meditated upon that is used to train Zen Buddhist monks to abandon ultimate dependence on reason and to force them into gaining sudden intuitive enlightenment
 
JM,

What part of the country are you located?
 
I also read the Forecast Discussion often. Yesterday's mentioned this...

Low Level Jet - A region of relatively strong winds in the lower part of the atmosphere. Specifically, it often refers to a southerly wind maximum in the boundary layer, common over the Plains states at night during the warm season (spring and summer). The term also may be used to describe a narrow zone of strong winds above the boundary layer, but in this sense the more proper term would be low-level jet stream.
 
scottd said:
Okay. Pretty simple. A TAF is a forecast for a terminal area. That's the area within the 5SM region around the center of the airport's runway complex. There's a surface observation (METAR) issued at that airport as well. A forecaster is only concerned about what happens in that 5SM area when issuing a TAF. In fact, he/she mostly cares about how the forecast will match up with the METAR. If the forecast is for light winds and light winds are only reported at the airport, the forecaster has done his/her job.

So, if there's a high wind event "near" but not in that 5SM area and that high wind event is never recorded by the surface observing equipment at the airport, then the forecaster has done his/her job.
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I understand. I guess I should clarify that the local airport AWOS did report these winds a few minutes after I noticed them. I'm not trying to understand why the local airport weather never had this event, I am trying to understand why it happened. The METAR did not report this and the TAF did not forecast this.

This is what I am trying to understand. I would like to know how this type of event could happen out of nowhere. I understand that forecasts are only as good as they can be, but from a forecast of low to calm wind and getting 40+ suddenly, something was missed.
 
RV10flyer said:
I also read the Forecast Discussion often. Yesterday's mentioned this...

Low Level Jet - A region of relatively strong winds in the lower part of the atmosphere. Specifically, it often refers to a southerly wind maximum in the boundary layer, common over the Plains states at night during the warm season (spring and summer). The term also may be used to describe a narrow zone of strong winds above the boundary layer, but in this sense the more proper term would be low-level jet stream.
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Is this something they are discussing that would be in the forecast or would they omit that information in a TAF if it were to be effected?
 
I "discovered" the TAF discussions a few months ago, and now they've become a standard part of my flight planning - I think they're great, and really flesh out the forecast and why the forecaster forecasted what they forecast. (huh?) You'll commonly see things like "some models show a slight chance for TS, but other models disagree so I have chosen to not include it in the TAFs". Stuff like that. Some of the forecasters write more than others, some explain it in simple words, others use a lot of abbreviations and meteorological terms, but overall they're very useful.

Here's the current one for my area.

A COLD FRONT HAS CLEARED THROUGH THE TAF SITES...AND BY 12Z...ALL PRECIPITATION SHOULD BE COMPLETED. WESTERLY WINDS BEHIND THE FRONT WILL CONTINUE TO BE GUSTY THROUGH THE DAY. GUSTS INTO THE MIDDLE TO POSSIBLY UPPER 20S WILL BE EXPECTED. LOW CLOUDS WILL ALSO CONTINUE TO BE A CONCERN...PARTICULARLY EARLY IN THE TAF PERIOD. THE CINCINNATI TAF SITES WILL LIKELY LIFT TO VFR (AND MAYBE INTO PATCHES OF CLEAR SKIES) WITHIN A FEW HOURS...BUT WITH QUITE A BIT MORE MOISTURE TO THE NORTH...THE DAYTON AND COLUMBUS TAF SITES MAY STAY MVFR UNTIL EARLY AFTERNOON. BRIEF PERIODS OF IFR CEILINGS WILL STILL OCCUR IN CENTRAL OHIO DURING THE FIRST FEW HOURS OF THE TAFS. ONE CHANGE FOR THIS SET OF TAFS WAS THE INTRODUCTION OF VCSH TO THE DAYTON AND COLUMBUS TAFS DURING THE AFTERNOON. HIGH-RESOLUTION MODEL DATA IS DEPICTING THE DEVELOPMENT OF CONVECTIVE SHOWERS. THESE SHOWERS WILL BE MORE LIKELY TO THE NORTH...AND THEIR HIT-OR-MISS NATURE WILL PRECLUDE PREVAILING PRECIPITATION IN THE TAFS. HOWEVER...CONFIDENCE HAS INCREASED IN THIS POSSIBILITY. OVERNIGHT...WINDS WILL DIMINISH SOMEWHAT...BUT SHOULD STAY IN THE 5-10 KNOT RANGE. ALTHOUGH SKIES SHOULD BE QUITE A BIT MORE CLEAR THAN NOW...THERE APPEARS TO BE SOME POSSIBILITY OF LOW VFR / HIGH-END MVFR CEILINGS AT DAYTON. OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
 
Jason- remember, what we have is a mesoscale weather system. Scott may find something. but MESO means MESO, not micro.
 
bbchien said:
Jason- remember, what we have is a mesoscale weather system. Scott may find something. but MESO means MESO, not micro.
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Dr. Bruce, I am trying hard to understand weather, but the more I try to learn about it, the more it throws in obstacles/phenomenons that are hard to understand. I'm finding it a challenge to trust a good forecast, I cant imagine you guys up in IMC and hoping you judged that information correctly.

It's this wind that worry's me the most, because I am still learning how to land correctly and the wind that has been my nemesis every single day. I can see the clouds and the rain coming, but I cant see an instant 40+ gust. shame there is not a good way to predict this.
 
JasonM said:
Dr. Bruce, I am trying hard to understand weather, but the more I try to learn about it, the more it throws in obstacles/phenomenons that are hard to understand. I'm finding it a challenge to trust a good forecast, I cant imagine you guys up in IMC and hoping you judged that information correctly.

It's this wind that worry's me the most, because I am still learning how to land correctly and the wind that has been my nemesis every single day. I can see the clouds and the rain coming, but I cant see an instant 40+ gust. shame there is not a good way to predict this.
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No worries. Wind is mostly a problem when you are trying to land. If you don't like what you see, keep going around until you do. If the crosswind is too great, climb and find a different airport with different winds or a more appropriately aligned runway.

I do believe the trick is having a plan.
 
Yup, weather is a complex beast. You're not going to master it by reading a chapter in a ground school book. That will just get you started.

Observe microweather in action as best you can -- clouds forming, motion of showers, wind blowing cornfields or the surface of a large lake or ocean, etc. -- and you'll start to understand why it's never reasonable to expect a forecast to predict every gust of wind or every rain shower.

People get advanced degrees and spend whole careers studying this stuff.
 
ChrisK said:
No worries. Wind is mostly a problem when you are trying to land. If you don't like what you see, keep going around until you do. If the crosswind is too great, climb and find a different airport with different winds or a more appropriately aligned runway.

I do believe the trick is having a plan.
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I would absolutely have that state of mind once I was on my own. i'm currently sitting next to my instructor and we have been challenged every single time we go up with gusting winds. One time we went up and got above 4500 ft and it was calm. I couldn't believe how calm it was. My last lesson out the AWOS reported 12kt 18G (was forecast to be 7kts btw..) direct headwind on landing and the windsock showed the same. Right after the windsock was passed and I was about to touchdown, that wind changed to about a direct crosswind and that really messed me up. I never thought landing would be this challenging in the wind.
 
MAKG1 said:
People get advanced degrees and spend whole careers studying this stuff.
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That's true and a good way to look at it. Guess, I'll just have to trust what I can and understand what I can. I'm sure as heck not getting a degree in weather anytime soon.
 
JasonM said:
I would absolutely have that state of mind once I was on my own. i'm currently sitting next to my instructor and we have been challenged every single time we go up with gusting winds. One time we went up and got above 4500 ft and it was calm. I couldn't believe how calm it was. My last lesson out the AWOS reported 12kt 18G (was forecast to be 7kts btw..) direct headwind on landing and the windsock showed the same. Right after the windsock was passed and I was about to touchdown, that wind changed to about a direct crosswind and that really messed me up. I never thought landing would be this challenging in the wind.
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Most student pilots feel this way. Your instructor is exposing you to situations that will challenge you, and you have nothing to worry about when he is in the right seat. Once you are on your own, you will get to decide if you are ok with the conditions before you go.

Remember that the METAR does not necessarily represent current conditions at the airport! Just look for that windsock and make your call.

Often when pilots get more experience, they enjoy more challenging landings. I've seen many a pilot here wax poetic about some crosswind or gust factor. It just takes time and experience. Keep flying and you will accumulate both!
 
ChrisK said:
Most student pilots feel this way. Your instructor is exposing you to situations that will challenge you, and you have nothing to worry about when he is in the right seat. Once you are on your own, you will get to decide if you are ok with the conditions before you go.

Remember that the METAR does not necessarily represent current conditions at the airport! Just look for that windsock and make your call.

Often when pilots get more experience, they enjoy more challenging landings. I've seen many a pilot here wax poetic about some crosswind or gust factor. It just takes time and experience. Keep flying and you will accumulate both!
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Thanks for the encouragement ChrisK! I'm going to keep at it for sure and just hope things will come together sooner than later.:)
 
The specific situation described by the OP definitely sounds like a front passing through.

I like to read the Forecaster Discussions on http://wunderground.com. Search for the relevant location then click "Scientific Forecaster Discussion" on the bottom of the forecast box. It's the same content direct from the weather service but Weather Underground adjusts the formatting to expand some common abbreviations and eliminate the ALL CAPITALS TEXT WHICH I FIND HARD TO READ. Reading Forecaster Discussions even with no flights planned has done a lot to improve my understanding of meteorological phenomenon and made me a safer pilot. Plus the discussions are often an excellent mix of formal and informal discussion and often have a bit of dry humor or amusing excitement when big weather rolls through.
 
LDJones said:
And even they can't tell you with any certainty what the weather will be doing in three days.
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Depends on the situation.

It's a good bet that July 4 in the SF Bay Area will start with patchy morning low clouds and fog around the Bay until around 11 AM, when it will clear and slowly transform into 10-15 knot west to northwest winds.

You can predict that conditions for thunderstorms will exist, but the detailed tracks of those thunderstorms is difficult a few hours ahead and impossible more than that.
 
Remember. Forecast = someone's guess. Albeit a well educated guess, it's still a guess. Kind of like medecine, Dr's are people who PRACTICE medicin.
 
scottd said:
You are correct. Nobody knows the future for certain. The forecaster's job is to quantify uncertainty and that's ultimately the product we will use to make our weather-related decisions.
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No, he's not. There is a huge amount of difference between an estimate and a guess. Guesses do not involve multiple models with data input from several types of observations spread all over the globe.

Every conclusion ever drawn is an estimate at best. No measurement is exact. Does that make every measurement a guess? Or can we be satisfied that every molecule of air in the room is exceedingly unlikely to spontaneously fly out the door and make a vacuum? It's not impossible -- which means the temperature, density and pressure in the room is an estimate even if you catalog every molecule -- but it's very confident that it won't happen in the age of the universe.

That a prediction has uncertainty does not make it a guess. Every measurement has uncertainty. Did you fly that approach at 65 KIAS exactly? Or might it have been 66...or 65.1?
 
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JasonM said:
I understand. I guess I should clarify that the local airport AWOS did report these winds a few minutes after I noticed them. I'm not trying to understand why the local airport weather never had this event, I am trying to understand why it happened. The METAR did not report this and the TAF did not forecast this.

This is what I am trying to understand. I would like to know how this type of event could happen out of nowhere. I understand that forecasts are only as good as they can be, but from a forecast of low to calm wind and getting 40+ suddenly, something was missed.
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Wind reports are notoriously inaccurate. Had a night flight 2 years ago that indicated winds calm all night. Double checked with FSS as there was a recent storm that moved through hours earlier and was now over 150 miles to the east and was told should be a great night to fly. Winds were calm upto my 5th stop-n-go and then I started losing the city lights of our sister-city Juarez MX. Thought there might be precip in the area, but tower said nothing in area (was a dust storm but I was still in calm wind). Lear jet landing from the west indicated there was a HUGE windstorm in the area I needed to land (home drome to the west). Winds were indeed 30G44 direct crosswind when I reached the home drome. Flew through TB to Las Cruces NM (as I did not want to catch mountain wave returning the the Class C I had just left) and landed for the evening (no wind at Las Cruces - but it did arrive hours later there as well even though it is only 30 miles north). By now it was midnight. Slept in the back of the plane (chained down) and flew out at sun-up the next morning 6 am with no wind. Stuff happens, and I nor FSS expected these winds.

Have had the reverse as well, flying in high head winds that were smooth as silk.

Have a Plan A, B and C at all times and you'll be fine. On that night flight above, I had enough fuel to reach California if I had to ... I run full fuel most of the time.
 
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