  y most accounts, this year's weather has been somewhat unusual across Texas and much of the nation.
Consider this -- for the first time in more than 15 years Austin saw nearly an inch of snow on Feb. 14. The first half of this year has been wetter than normal, with the month of June the second wettest ever recorded. Temperatures were unusually mild this summer, thanks to periods of rain and several rare cold fronts in July and August. Only one 100-degree temperature was recorded all summer.
When the tropical Atlantic became active in August, eight storms developed into either a tropical storm or hurricane-a new record. And Florida turned out to be a magnet for storms, being hit by four hurricanes and a tropical storm.
When you put all of these occurrences together, it makes you wonder what is going on with the weather this year.
Shifts in Pacific, Atlantic oceans having big impact
Much of this year's unusual weather is believed to be the result of shifts in the position of warm and cool in the world's two largest oceans. Because the oceans have an enormous influence on Earth's weather, shifting temperatures in the oceans can have a big impact on the position of the jet stream and the resultant weather.
Over the past few years, the Pacific Ocean has transitioned from having relatively cool water west and the warmest water east, to just the opposite. Today, the coolest Pacific waters are found over eastern sections, with the warmest waters now over the west and northwest. These large-scale changes in the Pacific waters typically last for a couple of decades and often have a large effect on regional weather patterns.
In the Atlantic Ocean over the past few years, water temperatures have become unusually warm over western sections and off the East Coast. This particular position of the warm water has been a large factor in the high number of tropical storms and hurricanes this season.
Sun another possible factor
Another possible factor in this year's strange weather could involve the sun. The sun operates on an 11-year cycle of activity that shifts from a high number of sun spots and high solar energy to a period of relative quiet. The sun is quickly approaching a solar minimum, and this decrease in the sun's energy may have some influence on the Earth's atmosphere.
Although this year's weather has been unusual, I think it's just a part of the natural variability in the Earth's long-term weather patterns. Some years are going to be better than others, and some years are going to be cooler than others. In some odd years, like this one, many of these extremes in temperature and rainfall will occur at the same time.
The oceans and the sun have enormous impacts on our weather, and subtle shifts in either one can have a big impact on what we like to call normal weather.
Bob Rose is LCRA's chief meteorologist. You can write him at bob.rose@lcra.org.
Other weather columns
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