Questions tagged [weather]
Weather means the atmospheric conditions, including wind, temperature and precipitation, in a specific area at a specific time.
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How is cloud height measured?
In general, cloud height is measured from ground or AMSL (above mean sea level)?
If they measure from AMSL, how are low level clouds' height measured in higher terrain?
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When temperature increases what happens to the air molecules and aircraft while landing and takeoff during hot weather? [closed]
Just out of curiosity on a hot weather with temperature increases what happens to the air molecules and aircraft during landing and takeoff?
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How to calculate outside air temperature at a certain altitude?
I am a PPL student and working on the cross-country planning.
Let's say the OAT is -13º @ 6000', how to calculate the OAT @ 7000'?
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What does "With One Minute Weather" Mean?
Yesterday I was listening to LiveATC at McClellan Field (KMCC) since many CAL Fire Tankers are stationed there and there's a lot of activity recently.
As the tankers returned from their bombing runs, ...
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On a METAR, what does DSPTD mean?
KDEN is currently reporting the following METAR:
SPECI KDEN 090325Z 34031G37KT 10SM -PLRA FEW015 OVC036 08/03 A2992 RMK AO2 PK WND 35037/0325 RAB04PLB25 TS DSPTD P0000 T00830028 $
I have no idea ...
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How are altimeter settings estimated?
So, I spotted another weird METAR from the same place that spawned the first one I asked about (it's a USAF base if you're wondering what kind of 'drome it is):
K... 060846Z 00000KT 10SM OVC002 18/...
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What does this A320 FCTM quote about cold weather and non-precision approaches mean? [closed]
Can someone explain this paragraph from the A320 FCTM about minimum temperatures for non-precision approaches? I can't understand it.
COLD WEATHER OPERATIONS For all Non Precision Approaches, there ...
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How can a crew be warned of "Clear Air Turbulence" during the flight?
Is there any piece of equipment, on board, to assist the crew to identify and avoid clear air turbulence (CAT)?
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Why is a TFR issued when barometric pressure exceeds 31.00 InHg?
Why does a barometric pressure above 31.00 InHg trigger a TFR?
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What does the code FU1FU2FU5 mean in this metar?
In their METAR, CYPK reported ... 25SM FEW037 SCT050 OVC250 21/15 A3016 RMK FU1FU2FU5 DENSITY ALT 400FT.
Since it's quite smokey out, I would have expected a ...
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What is the physical definition of turbulence?
To aviators, the definition of turbulence by measuring the results is widely known: example. But if we were to generate a turbulence forecast as a meteorologist, there need to be some kind of physical ...
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Aircraft lightning: What are the requirements for airworthiness?
Can you enlighten me about the airworthiness requirements in the field of lightning, for commercial aviation:
Which voltage or intensity is the aircraft required to sustain?
How is it demonstrated in ...
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What is this weird format (R06L/CLRD62) in METAR for runway being cleared?
Yesterday, this metar was published:
METAR UUEE 292000Z 07003MPS CAVOK 17/12 Q1013 R06L/CLRD62 R06R/CLRD62 NOSIG=
Can someone explain the meaning of the ...
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How is wind measured at this small U.S. airport?
While launching gliders at Front Royal, VA (KFRR) over the weekend, a fellow pilot and I got curious about the airport's weather equipment. We know that KFRR has local equipment to measure wind speed ...
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Where to find US airport weather Service Levels?
Where can I find an airport's level of service for weather services?
In other words, how do I know if a given airport's Service Standard is a categorized as Service Level A, B, C and D?
For ...
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What are the criteria for "variable" in METAR reports?
Regarding variable wind direction in METAR reports, what are the criteria for VARIABLE when the authority uses "VRB"?
An Advisory Circular mentions the authority uses "V" when the wind direction ...
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How can you identify the upwind side of a thunderstorm, and why should you fly there?
When flying around a thunderstorm, it is advised that you fly in the upwind portion of the thunderstorm. First off, how do you figure out which side is the upwind and downwind of a thunderstorm? ...
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What is the date of first use of the TAF format?
Unlike METAR and NOTAM, I cannot find any history on Terminal Aerodrome Forecast (TAF). Any hint as to the age of the format would be appreciated.
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What are the consequences of hail damage to a small GA plane?
I recently found a Cessna 172 that had been totaled by the insurance company because of hail damage.
The PDF from that page has detailed pictures which show hail-divots all over the the wings, body ...
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How should I interpret this TAF involving TEMPO and BECMG blocks?
with the reference in the TAF below , I was looking for the VIS at 0500 UTC and I was little bit confused because of the " TEMPO "
And the TAF was
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How does a jetstream boost an aircraft's speed? [duplicate]
Jetstreams are streams of high-moving west-to-east winds (200mph to 300mph, source) which most pilots are trained to use to cut down on their fuel costs (source). In the same linked article, it ...
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In an unpressurized cabin, why is the cockpit ambient pressure lower than the outside pressure?
As I study for my IRA written, this (VFR) question resurfaced and continues to irk me. The annotations cite the Venturi effect as the sole reason, but I don't follow.
From Wikipedia: "The Venturi ...
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How can a "due regard" state flight that has been intercepted indicate to their interceptor that they need to deviate around a hazard?
Military (state) aircraft sometimes conduct observation and intelligence-gathering flights near (but not within) the territorial airspaces of other countries, flying without the express permission of ...
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What are "approved weather reporting services" and do they apply to part 91?
When I look up Torrance Zamperini (KTOA) alternate minimums, it states, "NA when control tower closed, except for operators with approved weather reporting services."
My main questions are:
Can ...
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What is the most critical takeoff shear margin condition for a Type IV anti-ice fluid?
Type II and the more common Type IV anti-ice fluids use non-Newtonian thickening agents so that they can stay put during ground operations, yet shear stresses on the fluid during the takeoff roll ...
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What is the difference between saturated and unsaturated adiabatic lapse rate? [closed]
I'm having trouble understanding the difference between saturated and unsaturated adiabatic lapse rate.
I know the unsaturated adiabatic lapse rate is approximately 5.4 degrees per 1,000 feet in ...
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What are ISA +10, ISA -15 and ISA -30?
I have found out that an ISA atmosphere is:
15 °C temperature
5 °C dewpoint
1013.25 hPa pressure
What are the conditions of an ISA +10, ISA -15 and ISA -30? I know the temperature, but what are ...
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Is there a detection method available to detect a plane without using RADAR? [closed]
If we don't have RADAR, is there any other method to detect flying objects?
All flying objects disturb the air around them. Is there any method by which we can detect that this air turbulence is from ...
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How are winds aloft forecasts derived in the USA?
This question pertains specifically to the US NWS FB Forecast Product.
Winds aloft forecasts, technically the "Wind and Temperature Aloft Forecast (FB)", are issued 4x daily, at 00, 06, 12, and 18z. ...
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Adding moisture creating fog? [duplicate]
It may be a simple question and I've read the PHAK and searched online, but I can't seem to understand why adding moisture to a dry cold air mass would create fog. I understand when an air parcel is ...
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Why airliners fly so high even when winds are more suitable at a lower altitude? [duplicate]
While playing a flight sim, I noticed West winds were very strong at levels >FL350 and weaker around FL270 above the US.
I took a look at Flight Radar 24 to see at which level actual airliners were ...
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How do the FAR's define a cloud?
If you're talking about a big puffy cumulus cloud it's pretty obvious. But from where I am right now, looking up I see grey sky from horizon to horizon. But visibility at the surface is good. All ...
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How does one determine runway orientation without a local wind rose?
We are planning to establish new airport, but then we have no wind rose analysis of the location.
How can we predict what's the right orientation for the runway that satisfies the 95.
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How can a pilot anticipate cloud formation?
I read a few articles and a book about cloud forming, but I didn't really understand it.
Can anybody explain in simple terms how clouds form?
As a pilot, what factors that contribute to cloud ...
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Are ground crews at danger for radiation from WX radar? [duplicate]
I am under the impression that the radiation from a weather radar on the nose/wing of aircraft can cause enough radiation to render ground workers sterile/cause cellular damage if the pilot forgets to ...
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Why is wing anti-ice in transport aircraft not required below -40 degrees Celsius?
Okay, this confuses me. As it gets colder doesn't it mean more possibility of icing? And is the -40 degrees SAT or TAT?
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Is the weather radar on and active during the whole flight?
The title says it all: Do airline pilots leave the aircraft's weather radar on at all times during the flight and display the data on one or both of the Navigation Displays, or only if clouds/ weather ...
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How do SIGMETs arrive in a cockpit on a modern longhaul flight?
What is todays medium of choice (Voice Radio, ACARS,CPDLC,…) to receive SIGMET messages on a commercial longhaul flight, for example from continental Europe to the US westcoast?
Are there any ...
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Can lasers be used for weather detection along an aircraft's flight path?
Aircraft use RADAR for weather detection such as storm clouds, rain, etc. Why don't they use LASER instead to measure the density of the weather ahead?
RADAR has been known to return false signals of ...
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How can a private pilot prepare for a long cross country flight in an unfamiliar area?
TL/DR: What are common preparation tips or techniques for low-hour private pilots planning long cross country flights in unfamiliar territory?
I got my private pilot's license in November 2016 in ...
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Under what conditions can a flight continue beyond the point of in-flight re-planning?
I'm studying ICAO Annex 6, but I am confused a little bit about the paragraph below:
6-2.2.3.4.2(b)
A flight to be conducted in accordance with the instrument flight
rules shall not take off or ...
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What would happen if an airplane flew through a tornado?
I read a question which asked whether planes fly over hurricanes, so my question is what would happen if a low-flying commercial plane tried to fly through a tornado.
Assume that it's traveling at ...
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What is the relationship between temperature, dew point and the formation of clouds?
What can you infer from the temperature / dew point values in this METAR?
EGJG 121630Z 09012KT 9999 SCT006 15/14 Q1015
I understand the temperature is 15 degrees and the dew point is 14, and I ...
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What does "Constant wind condition during flight" mean?
What is constant wind condition during flight? Is it zero wind velocity at an instant (say at level flight) or wind with constant speed, say 20 m/sec (at steady level flight or whatever it is) Which ...
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What is the weather term for snow and dust mixture?
An old pilot friend of mine told me today a story that I thought was interesting.
He said that he was flying into Wichita, KS a couple decades ago and was listening to the ATIS when the weather ...
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To what extent are (non-urgent) PIREPs used by meteorologists?
It's inevitable. At some point during your weather briefing, some underpaid, underappreciated briefer will say "Pilot reports are requested." and you'll say "Certainly, my good sir or madam! Why, the ...
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Why would METARs and ATIS both report exactly the same wind direction?
I understand that METARs report wind direction as true and ATIS reports it as magnetic. But at Camarillo (KCMA) both are reporting the same wind direction and speed even though the magnetic variation ...
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What is the icing probability required for an AIRMET?
For an icing AIRMET to be issued, moderate icing must be forecast over an area of at least 3,000 square miles. What probability of moderate icing is required before that AIRMET will be issued?
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Aerodrome actual weather - METAR decode - 3 letters for this sky?
How can I describe this sky, in 3 letters as per the Aerodrome actual weather - METAR decode?
I found online a comprehensive list of Metar codes
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Are solar / geomagnetic storms real risks for commercial aviation?
Background
Solar storms/flares are solar events sending particles in space that are potentially dangerous on Earth. From Wikipedia:
Solar flares strongly influence the local space weather in the
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