The eastern Pacific hurricane season began Tuesday, but the atmosphere jumped the gun by a day producing the first tropical storm of the season.
As AccuWeather.com Meteorologist Eric Leister recently pointed out, a system roughly 640 miles south-southwest of Manzanillo, Mexico was a candidate for the 2012 season's first tropical cyclone in the eastern Pacific.
Tropical Depression One-E, which formed on Monday was upgraded to Tropical Storm Aletta later the same day.
At 2:00 a.m. PDT, Wednesday, May 16, 2012, the system was located near 11.9 North and 111.7 West, or about 770 miles south of the tip of Baja California, Mexico, with sustained winds estimated near 40 mph.
Aletta is expected to continue to track just slight north of west as it moves farther away from Mexico.
We had been observing clusters of thunderstorms fluctuating in strength in the region since late last week.
One particular cluster of storms was located within a low pressure area and remains in a favorable zone for additional development with low wind shear and sufficiently warm water.
A tropical storm forms when a low-level circulation is present.
According to Tropical Weather Expert Dan Kottlowski, "Investigations of the system, including satellite microwave technology, over this past weekend proved to be inconclusive."
The technology provides the ability to detect low-level circulation of a storm system through thick cloud cover and where no surface or aircraft observations are present.
"During this past weekend, the area of disturbed weather had a circulation in the mid-levels of the atmosphere, but not the low levels," Kottlowski said.
On Monday however, this area of disturbed weather formed a low-level circulation. This characteristic, in addition to stronger winds classified the system as a tropical depression. Subsequently, it has strengthened into a tropical storm.
Despite the increase in strength, the clock is ticking on the favorable zone for further development and survival for the system.
"After a couple of days the system would encounter cooler water and likely significant wind shear," Kottlowski said.
At any rate, the system is not a threat to land.
Meteorologist Dan DePodwin contributed to this story.
Severe thunderstorms with the risk of a few tornadoes will advance eastward across the northern Plains and Upper Midwest into Friday.
A dangerous outbreak of severe storms will strike the northern High Plains and Canadian Prairies on Wednesday.
Join us on Thursday for AccuWeather LIVE as we will discuss the debate of climate change and hurricane frequency and the top five things you need to know about summer weather.
A hot and humid weekend is shaping up for Chicagoland just in time for the official start of summer, while severe thunderstorms fire nearby to the north.
Tropical Storm Barry formed over the southwestern Gulf of Mexico and may hit the Mexico state of Veracruz Thursday.
A tornado touched down at Denver International Airport as a severe weather system moved through the area.
Amwell, NJ (1742)
A fatal hailstorm and severe thunderstorm containing hail 4" in diameter killed one child and did considerable damage to crops.
Southeast China (1932)
Hailstorm in Hunan Province killed 20 people and injured thousands of others.
Philadelphia, PA (1994)
Strong thunderstorm winds blew off a large section of a hanger roof and also damaged two aircraft.