Calvin weakens to a post-tropical remnant low over the Pacific

[News_Editor]

Calvin weakens to a post-tropical remnant low over the Pacific

2011-07-10 11:45:08 GMT+7 (ICT)

MIAMI (BNO NEWS) -- Tropical Storm Calvin weakened to a post-tropical remnant low on Saturday evening as it stayed far off the Pacific coast of Mexico, forecasters said.

Forecasters at the U.S. National Hurricane Center (NHC) have been following the weather system since last Sunday when it emerged as an area of disorganized showers off central America. It slowly became more organized and developed into a tropical depression on Thursday morning, before strengthening into a tropical storm about 12 hours later.

Calvin briefly became a category one hurricane on Friday afternoon with maximum sustained winds around 80 miles (130 kilometers) per hour. But Calvin - which at all times stayed far from land - weakened back to a tropical storm on Saturday as the storm moved over cool waters.

As of 8 p.m. PDT on Saturday (0300 GMT Sunday), the center of Calvin was located about 400 miles (645 kilometers) south-southwest of the southern tip of Baja California in Mexico. It is moving toward the west-northwest at a speed of 10 miles (17 kilometers) per hour.

"Infrared and microwave satellite imagery indicate that Calvin has continued to rapidly degenerate," NHC senior hurricane specialist Stacy Stewart said. "There has been no organized deep convection near the low-level center for nearly 9 hours now, and [new data] indicated that the upper-level warm core had dissipated with only a weak warm core remaining."

Stewart noted that a small thunderstorm has recently developed about 70 nautical miles (129 kilometers) southwest of the storm's center, but this was not expected to strengthen Calvin. "As a result, Calvin has been declared a non-convective remnant low pressure system," he added.

Maximum sustained winds of Calvin have now decreased to near 35 miles (55 kilometers) per hour, with higher gusts, according to forecasters. "Additional weakening is forecast during the next 48 hours, and the low is expected to dissipate during the next couple of days," Stewart said.

Calvin is the third named storm of the 2011 Eastern Pacific hurricane season and followed Hurricane Beatriz which formed off the Pacific coast of Mexico in late June. Beatriz caused heavy rains and strong winds in the region as it moved along the coast, killing four people in Guerrero state.

Before Beatriz, Hurricane Adrian formed off Mexico's Acapulco in early June. It rapidly strengthened into a category four hurricane but had no direct impact on land. Adrian eventually dissipated on June 12.

According to figures released in May, NOAA's Climate Prediction Center is expecting a below normal hurricane season in the Eastern Pacific this year. The outlook calls for 9 to 15 named storms, with five to eight becoming hurricanes and one to three expected to become a major hurricane (category 3 or higher).

An average Eastern Pacific hurricane season produces 15 to 16 named storms, with eight to nine becoming hurricanes and four becoming major hurricanes. The Eastern Pacific hurricane season runs from May 15 through November 30, with peak activity from July through September.

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