Questions tagged [meteorology]
The study of how the earth's atmosphere works, including weather forecasting. Use this tag for questions about the earth's weather. When asking questions specifically about the atmosphere, also include the [atmosphere] tag.
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How common is it for warm fronts to be responsible for record high temperatures?
Warm fronts are associated with an increase in temperature and precipitation.
But are they often associated with record high daily maximum temperatures, given that they often result in an increase in ...
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What determines the differences in results between various weather models?
It's often said that the ECMWF model is more accurate than the GFS. But what are the reasons why? Also, how does the NAM compare with these two and other forecasting models?
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What determines the eastward speed that mid-latitude high pressure/low pressure systems move at?
Do they move at the group velocity of Rossby Waves? Or do they move at the phase velocity of Rossby Waves? Or some other speed?
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How are jet streaks formed?
"Jet Streak Dynamics I: The four-quadrant model" - explains their effects on frontogenesis.
But how are they formed to begin with?
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Why is Montana warmer than Wyoming?
The National Climatic Data Center (NCDC) data shows the mean temperature from 1971-2000 for Montana was 5.97°C (42.74°F) and Wyoming's was 5.54°C (41.98°F).
Montana is at a higher latitude, so this ...
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Is it possible for a sting jet to form over a continental landmass?
Sting jets are thought to be responsible for some of the most damaging winds associated with extratropical cyclones in the mid-latitudes. So far they have only been confirmed in the European region, ...
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What constitutes a blizzard in meterological terms?
Blizzards are most commonly associated with a large amount of snowfall and low visibility. However, snow squalls can induce low visibility whereas a 12" snowfall doesn't have to induce low visibility.
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Why is the Atlantic Hurricane Season defined as being between June 1 and November 30?
Historically, the Atlantic Hurricane Season has shifted, as close as June 15 to October 31, but since 1965, it has been between June 1 and November 30(1).
Why is the Atlantic Hurricane Season defined ...
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How accurate are climate proxies in giving us a clear picture of global average temperatures throughout Earth history?
Since reliable modern records of climate only began in the 1880s, proxies provide a means for scientists to determine climatic patterns before record-keeping began, though it appears that the the ...
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What is the motivation of using the Enhanced Fujita Scale in place of the Fujita Scale?
In 2007, the US started using an Enhanced Fujita Scale in place of the Fujita Scale. From a "civilian's" perspective, the Fujita Scale seemed to measure wind whereas the Enhanced Fujita Scale measures ...
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What is the difference between a "flood" and a "flash flood"?
Whenever weather warnings come up, I have heard of both a flood watch/warning and a flash flood watch/warning.
What is the difference between a "flood" and a "flash flood"? Are there any specific ...
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Why do more tornadoes happen late in the day?
According to the graph below, which appears to be sourced from the US National Oceanic and Atmospheric Administration, more tornadoes happen late in the day - why is this?
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Cloud-to-ground lightning in Florida?
I was looking into the odds of getting hit by lightning and ran across this map:
My first thought for this was due to a higher number of thunderstorms in Florida. However, the map for that doesn't ...
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Transfer precipitation forecast in mm to expected snowfall in cm
What conversion functions exist to transfer precipitation forecast in mm to expected snowfall in cm? Simple rules of thumbs as well as more advanced methods would be of interest.
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Does Earth's air leak into space over time?
From my current understanding, Earth's atmosphere and air are held by the balance of two forces: 1. Earth's gravity and 2. Air pressure from air out to space.
Is my understanding correct?
So, do ...
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Why does the rising of high clouds due to climate change impart positive radiative feedback on radiative forcing?
As seen in the figure below.
The larger the temperature difference between surface and cloud, the more positive the radiative forcing is from the cloud.
So as the cloud moves up, it supposedly ...
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Are clouds significantly easier to simulate in weather models than climate models?
Cloud forcing is still one of the major uncertainties of radiative forcing in climate modeling because there are so many uncertainties in it (and parametrizations). But also because the timescale of ...
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Why are most cirrus clouds present over the equator and over tropical continents?
As quoted from the AR5 IPCC report (chapter 7) here.
Most high cloud (mainly cirrus and deep cumulus
outflows) occurs near the equator and over tropical continents, but can
also be seen in ...
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How does the lapse rate in clouds compare with the lapse rate of air?
So moisture decreases the temperature lapse rate (relative to the dry adiabat). My question is this: does a cloud decrease the lapse rate at the same rate as 100% humidity would decrease it? Or would ...
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A good book or source for climate science and meteorology basics?
I have a mainly a hydro-geological and geo-statistical background, I would like to have a basic introduction to meteorological, climatic processes and modelling techniques related to these fields. Any ...
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What factors affect the size of rain shadows?
Rain shadows are dry areas on the lee side of mountains. Due to humid air condensing and precipitating as they are lifted up and over the mountains, they lose moisture by the time they reach the lee ...
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Bifurcation Scenarios in the Atmosphere
I read that the mathematical definition of bifurcation is that, at a critical value of a parameter that governs the dynamical system, the system changes to a topologically different system than the ...
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Why does the so called "tornado alley" exist?
75% of the world's tornadoes occur in the USA, and within the USA these tornadoes are most likely to occur in particular regions of the country, such as the well known "tornado alley". The diagram ...
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Will tropical cyclones form and be sustained in areas they previously were not due to global climate change?
With global climate change, is it possible that tropical cyclones (as seen in the Atlantic basin for example) are going to form and be sustained in regions where they previously did not, for example ...
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Where does wind come from?
Wind is (according to Wikipedia) the flow of gases on a large scale.On the surface of the Earth, wind consists of the bulk movement of air.
What forces would cause such a mass movement of air?
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How can I plot a Skew-T log-P diagram?
For displaying atmospheric soundings the use of Skew-T Log-P diagrams is very common. The manual THE USE OF SKEW T, LOG P DIAGRAM IN ANALYSIS AND FORECASTING from the Air Weather Service explains what ...
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Why do snowflakes form into hexagonal structures?
Snowflakes are known to form into pretty hexagonal structures. The image below shows a variety of such structures that are possible (although by all means not an exhaustive list):
What is the ...
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Why does the Hadley cell descend at 30 degrees latitude?
George Hadley's initial model of the Hadley cell described air as being heated at the equator, ascending, and then moving aloft pole-wards where it would cool and descend. Meanwhile surface air would ...
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Why does the meandering pattern of the jet stream itself propagate?
It is well known that the jet stream follows an overall meandering pattern, but what is less well known is that this meandering pattern itself moves as a wave with a velocity much slower than the ...
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What is the cause of the jet streams?
Jet streams are fast-flowing currents of air in our earth's atmosphere. An enormous amount of energy is necessary to keep a jet stream going. Where does this come from and why?
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What causes 'positive' lightning to be rarer, higher charged, and longer lasting than 'negative' lightning?
Why is 'positive' lightning rarer, brighter, higher charged, and longer lasting than 'negative' lightning? Are there any other unique characteristics to positive lightning that sets it apart from ...
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What do quasi-geostrophic and ageostrophic mean?
I know that geostrophic flow means straight wind flow that is balanced by the pressure gradient and Coriolis forces. But what do quasi-geostrophic and ageostrophic mean specifically?
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How is global weather model skill measured?
The models I have in mind are the major global models such as the Global Forecast System (GFS) and the European Center for Medium range Weather Forecasting (ECMWF).
These models produce numerous ...
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Why do tropical cyclones not tear themselves apart?
A tropical cyclone is the generic term for a hurricane, typhoon, or tropical storm. Tropical cyclones derive their energy from evaporation of water at the ocean surface which ultimately recondenses ...
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Is it true that a butterfly flapping its wings can result in a tornado in a distant location?
I have heard that extreme storm events can be caused simply by a butterfly flapping its wings somewhere in a distant location. Is it true that such a small disturbance in the air in one location can ...
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What are the key differences between warm and cold core cyclones?
What are the key differences between warm and cold core cyclones? What is an example of each?
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Impossible or improbable? Hurricane crossing the equator
No known hurricane has ever crossed the equator. Hurricanes require the Coriolis force to develop and generally form at least 5° away from the equator since the Coriolis force is zero there.
Are ...
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How do tropopause folds form and do they have any impact on synoptic scale weather?
What is the process that creates a tropopause fold? Do these features have any significant impact(s) on weather patterns or the atmosphere?
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How can I estimate a 2 m temperature from / in an atmospheric model?
Numerical models of the atmosphere usually have their first atmospheric grid level well above 2 m, but the temperature at 2 m above ground level is something one often wants to calculate with such a ...
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Can overshooting tops enter the stratosphere, or will they rather push the tropopause upward?
Convective overshooting tops
reach above the normally horizontal flat layer of the convective system, a layer that should coincide with the tropopause. If we have such an overshooting top, does this ...
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Does a green or yellow sky actually indicate a tornado?
It seems to be a fairly widely held belief that if the sky is green or yellow, a tornado may be developing/approaching. But is there any truth to it? Could the color of the sky actually be associated ...
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