Can someone tell me why it is sooo windy nearly every day?

[hlewis]

In all my life, I have never seen such a wind pattern. What is causing this? It's every, single day, it seems.... Earth changing?

[tireman4]

Pressure Gradients?

[hlewis]

What does that mean? Is this normal?? When was the last time you remember it being this windy, every day, for the last six weeks or so?

[srainhoutx]

Pressure Gradient:

Wind is simply the air in motion. Usually when we are talking about the wind it is the horizontal motion we are concerned about. If you hear a forecast of west winds of 10 to 20 mph that means the horizontal winds will be 10 to 20 mph FROM the west.

Although we cannot actually see the air moving we can measure its motion by the force that it applies on objects. For example, on a windy day leaves rustling or trees swaying indicate that the wind is blowing. Officially, a wind vane measures the wind direction and an anemometer measures the wind speed.

The vertical component of the wind is typically very small (except in thunderstorm updrafts) compared to the horizontal component, but is very important for determining the day to day weather. Rising air will cool, often to saturation, and can lead to clouds and precipitation. Sinking air warms causing evaporation of clouds and thus fair weather.

You have probably seen a surface map marked with H's and L's which indicate high and low pressure centers. Surrounding these "highs" and "lows" are lines called isobars. "Iso" means "equal" and a "bar" is a unit of pressure so an isobar means equal pressure. We connect these areas of equal pressure with a line. Everywhere along each line is constant pressure. The closer the isobars are packed together the stronger the pressure gradient is.

Pressure gradient is the difference in pressure between high and low pressure areas. Wind speed is directly proportional to the pressure gradient. This means the strongest winds are in the areas where the pressure gradient is the greatest.



http://www.srh.noaa.gov/jetstream/synoptic/wind.htm

[unome]

In all my life, I have never seen such a wind pattern. What is causing this? It's every, single day, it seems.... Earth changing?

North American Wind Power had this to say, though I think they were referring to 4th qtr 2010: http://www.nawindpower.com/e107_plugins ... ntent.7427

"In the U.S., near-neutral North Atlantic Oscillation and Pacific-North American patterns, a strong La Nina - a negative El Nino/Southern Oscillation (ENSO) - and a strong Bermuda high promoted windier-than-normal conditions for wind power plants throughout the Ohio River Valley, Mid-Atlantic and Northeast regions."

they also have a wind map posted (by http://www.3tier.com ), with variances from normal - here's March 2011:



"By Dr. Mark Stoelinga

Average 100-meter wind speeds for March were at or above the 1960-2010 normal for most of the contiguous U.S., except for the north central part of the country. Most of the Intermountain West and Pacific Northwest saw substantially positive wind anomalies, with March mean wind speeds exceeding 125% of normal in many locations. The above normal wind-speed conditions were less robust across the South and East, with average winds 0-15% above normal. Meanwhile, wind speeds over the northern part of the country; from the crest of the Rockies east to Michigan, ranged from 0-10% lower than normal. Other small pockets of lower-than-normal wind speeds were seen over the Appalachians, southern Florida, and southern Arizona.

Climate conditions across North America during March were characterized by a weakening La Niña in the tropical Pacific Ocean, a slightly positive Pacific North America pattern and a transition from a weak-positive to wea- negative North Atlantic Oscillation index during the month. With the latter two indices hovering near neutral conditions, it is not surprising to see a wind anomaly pattern roughly consistent with the remnant La Niña winter, with stronger winds in the western U.S. In addition, a series of strong frontal systems moved across the southern U.S. in March, producing above-normal incidence of severe weather, and this pattern may have likely contributed to the positive wind anomalies in the southeastern third of the country.

Dr. Mark Stoelinga is senior scientist for 3TIER, a Seattle-based renewable energy information service company.

About the map

The map illustrates departures from the long-term mean wind speed that range from -20% to 20% and show a pattern that is indicative of the climate state during March. The map was created by comparing output from 3TIER’s continually updated meteorological data set with wind conditions averaged over the 1969-2008 period from the same data set. Wind-speed values were computed using a numerical weather-prediction model run with a grid spacing of 15 km and adjusted using available observations."