Weather Definition and 178 Threads

I live in Denver CO, and I have come across a mystery having to do with barometric pressure. If you go look at any weather site, like: http://www.wunderground.com/cgi-bin/findweather/getForecast?query=denver+co You will see the local pressure (at the time of this writing) is listed as 30.33...

Are magnetic waves that travel ahead of low pressure wx fronts, a certain frequency? Are they a sign wave? Is it possible to cancel a magnetic wx front wave on a local basis by generating an 180 degree out of phase signal at the same frequency like you would a voltage wave? Is the magnetic wave...

http://arxiv.org/pdf/1401.5761v1.pdf Abstract: It has been suggested that the resolution of the information paradox for evaporating black holes is that the holes are surrounded by firewalls, bolts of outgoing radiation that would destroy any infalling observer. Such firewalls would break the...

Do neutron star, pulsars, magnetars etc. have solar flares like the sun or do they have sun spots like the sun or do they have solar winds and if they do have any of those types of weather, what are they called?

I thought this was a good article as I have also seen many of these same fake photos. Nice to know the truth. http://www.weather.com/news/news/fake-overused-weather-photos-20140421

Hi, I know this is an unusual question, but it's important to me. I'm looking for a physics master's program somewhere that has pleasant weather. All the reputable programs I can find are in the US or northern parts of Europe (Germany, England, etc.) I like warm and dry weather (family is from...

The day after the contest ended, we had nice weather... here's a few that were a day late and a dollar short:

I have an idea and a small concept of a school bus GPS system that is unique to school buses because it will include recent crime reports in passing areas of concern, weather reports to date, traffic reports to date, and of course the ability to hold multiple destinations at once. With this I...

Does anyone know of any research being done to control gravity and weather systems through computer science and directed programmatic control leveraging energy? There's a rumor on the 'internets' (as Bush would call it) that the senate recently discussed openly that HAARP and weather...

Hi all, I want to better understand the physics behind atmospheric phenomena, more out of curiosity than anything. What textbook would you recommend for me to study from? I'll be done my BS in physics next year, so that should tell you approximately what 'level' I'm at. TIA

I just read Source: http://www.princeton.edu/~oa/winter/wintcamp.shtml#Food This counters my intuition Can someone explain this to me? Thanks

Homework Statement An imperfect sensor measures the weather (which can only be either sunny, cloudy or rainy) in a fixed place. Suppose we know the weather on the first day was sunny. In the following days we obtain the measurements cloudy, cloudy, rainy, sunny. What is the probability...

Until yesterday, the southeastern US had escaped the snow and ice that the Northeast and Midwest have been dealing with repeatedly. Now it's our turn. The college where I work first announced late yesterday afternoon that classes would start and offices would open at 10 AM today (two-hour...

Hey guys. I was studying up jet-engines and their performances with varying ambient temperatures and found myself stuck on something that is probably very trivial. What I've read online and in my notes is all generally the same - that as temperature falls air density rises and as such more...

Hi Guys, I am not an engineer and was hoping someone could help me with a question I had about piping in cold weather. I am setting up a temporary 4" Bauer water pipe that I need to keep from freezing. It will be outside (non insulated) in February in Ohio. I am expecting temperature...

I currently have hard-coded in my forecasting model, 6 weightings (totaling 100%) for 6 weather stations and wish to determine a methodology to produce these weighting or conversion factors % to form an artificial single weather station. This is part of forecasting the electricity load in my...

http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10891966 Most hit last night. Where I am, Petone (15 min drive from Wellington) shop signs from roofs were down, a window smashed. Neighbourhoods have trees down. Schools closed. My Internet and TV is down (using mobile...

"Weather Balloon" and "Scuba Diving" relationships Hello so I am suppose to state any relationships between a "Weather Ballon" and "Scuba Diving" those could include equations, laws, both rely on a source etc. I know that for the weather balloon the higher you go up the less pressure there is...

I would like to know more about how the electron fluxes at geostationary orbit effects weather on Earth, I try google, but not much good materials directly related to this topic. Does anyone have any suggestions? Thanks in advance for any suggestions

I live about 2 miles away from the NOAA weather station in South Jersey. This covers all of NJ, northern Delaware, eastern Pennsylvania and southern New York. Today they had an open house. There were some Air Force soldiers doing a demonstration of their portable weather station and handheld...

Please help with this: Suppose in recent years, it has only rained an average of 5 days a year. The weather forecast, which has an accuracy of 90%, predicts rain for tomorrow. What is the probability of rain tomorrow? A: <1% B: between 5 and 15% C: between 15 and 80% D: between 80 and...

My friend and I had an idea to put camera on the weather balloon and we wanted to have like a live picture from camera. But because we don't know so much about electronics we don't know how to do it. Fe figured out that we can do it via radio waves, maybe there is some more efficient way. That...

I have seen the Probability of Precipitation defined as $\mathrm{PoP} = C \cdot A$ where $C$ is the confidence that measurable precipitation will occur somewhere within the forecast area during the forecast period, and $A$ is the percentage of the forecast area that will experience...

Is there a way to reclaim the Helium that I put into a weather balloon? Meaning, I empty out a cylinder of Helium into a weather balloon, and for some reason I want to get it back into the tank (bad weather, missed launch time, MacGyver is on, etc.) and can't launch my balloon. Is there a way...

Does anyone know the highest altitude the biggest industrial grade weather balloon can go?

I am writing a science fiction story, and would like some help from the PH community. Details: There is a cylindrical spaceship which is rotating to create artificial gravity. The cylinder has a circular radius of 10km and a length of 30km. The rotational period is 3 minutes and 20...

I live in the DC metro area and we recently had snow that lasted all day (none stuck to the roads, booo). But I didnt understand that it was still snowing at well above freezing. I have a digital thermometer outside of my window and it read ~41 degrees F at its highest and never dropped below 32...

Homework Statement A weather vane sits quietly on the roof of a barn on a calm winter's day. It has a length of x, is pole-shaped with mass M, and rotates frictionlessly about its center. But just now it is still. Suddenly Justin throws a snowball of mass m at speed v that hits it a...

I am thinking about doing a coat that could help keeping someone alive when sleeping in the streets in the winter. Where I live, temperatures can easily reach -30 degrees celsius. Assuming the coat is well insulated and that the heating element is all over the inside of the jacket, what kind...

Homework Statement A 1000 kg weather rocket is launched straight up. The rocket motor provides constant acceleration for 16 s, then the motor stops. The rocket altitude 20 s after launch is 5100 m. You can ignore any effects of air resistance. a) What was the rocket's acceleration during the...

I assume this is the right forum to ask this question Based on what I think I know, the Earth completes one full orbit of the Sun in approximately 365.25. Every four years we have a Leap year that adds one day. This I understand. What confuses me is how can Fall begin more than 24 hours...

Homework Statement This isn't a homework question, and in fact I have not yet taken probability, so I know very little about it. With that in mind, any attempts to "lead me through" this problem will almost definitely fail, so if you could just tell me, that would be best. If the...

(b]1. Homework Statement [/b] A spherical weather balloon has a radius of 1m when it is 1500m high. You observe that the radius increases at a rate of 2cm/min as it continues to rise. At what rate is the surface area increasing when the radius is 4m? Homework Equations I thought...

I would like to have a function f such that f(0) = 0 and f(x) = 1 for any x>0. I can compute f in the following way: f(x) = (2*x+1)/2 - (2*x-1)/2 . Here the division is integer division. But if x=0, here we divide (2*0-1)/2 or -1/2, which is a problem. Because we do not have any number -1...

Physics in the Weather? Homework Statement It isn't a crazy physics problem or anything I just have to list some of the things that are related to physics in weather forecasting. THe actual question is "what are some things weathermen need to know regarding physics?" I looked around and I...

Novice question :blushing: I've been reading Brian Greene's "The Hidden Reality". It occurred to me that spacetime across the 2D analog of the U could be much like an isometric weather map. Could it be that the U isn't expanding, but that our region, like a High on a weather map is rushing...

Here's my understanding... (P1V1)/T1 = (P2V2)/T2 P1 = starting pressure, typically sea level pressure which is 1atm. V1 = Starting volume of the gas inside your balloon. T1 = starting temperature, temperature at ground level. P2 = final pressure, this should be the pressure at your flight...

Hi. I'm planning to use an all-ocean planet as a setting in a science fiction story, and I was wondering, what would the effect of an absence of continents be on the planet's weather? The planet is something like 98% water-covered, its only land is a number of islands, mostly small, the...

I was checking out a developing blizzard forecast for the northeast US today when I saw this interesting fog feature over the South Dakota, Nebraska, Oklahoma area. http://www.weather.com/maps/maptype/currentweatherusnational/uscurrentweather_large.html EDIT: The image is changing. It was the...

What weather conditions are needed to produce fine snow rather than the big flaky wet snow. .

Hi I am starting a project and will be inflating a 900g Kaymount weather balloon with a payload that consists of a styrofoam box inside of that will be a SPOT personal gps tracker, Camera and a Flip HD camcorder. I purchased 2 of the 600g balloons. I will do this by filling one up and attatching...

I'm a high school physics teacher and my students are building a science payload to launch on a weather balloon. You can look http://www.donorschoose.org/donors/proposal.html?id=458390&challengeid=39361" to see some project details and even donate a couple bucks to help make the project a...

Hey, I am building a weather balloon with a small payload that will ascend to approximately 105,000 feet, pop, and then fall to the ground. I am having trouble coming up with a design for a parachute that will deploy after the balloon pops. There is obviously less air at that altitude, so if...

Hi all, I am wondering that we should choose fast or slow function of electric Fan in hot weather, which function will spend much more of energy?, can someone give me an explanation :D Forgive me if the questions is silly

In terms of damage (if any) - What can a Hyder Flare cause? http://spaceweather.com/"

A weather station at the airport measured a station pressure of 1014 mb. The density of dry air is 1.3 kg/m^3. The gas constant for dry air, R, is 287 J/kg-K. Calculate the temperature of the dry air at the airport. 1 mb = 100 J/m ^3 AND The surface pressure at the airport then decreased to...

Hello guys, first post ;p I am currently doing an info search for physics at school about weather and communication satellites. I'm not 100% sure if they're right because I've surfed the web and either get too broad answers or one that makes no sense lol At the moment, my understanding of how...

Why are clothes becoming darker when they are wet?

It looks like Yellowstone WY beat the all time low record of 1998 for 10 December (-22 C) with a remarkable big margin: -31C. The page updates all the time so I include a screenshot. But of course, when it's hot then it's global warming and when it's cold then it's natural variability

Homework Statement assume the balloon is a spherical shape whose radius is 2.5m and total mass of 15 kg a) what is the initial upward acceleration of the balloon when it is released from sea level Homework Equations The Attempt at a Solution i know the volume of a sphere is...