NATIONAL STORM SUMMARY

 

MARCH 2012

 

1^st-10…The cold front that was responsible for the disaster on Friday continued to advance eastward and brought strong to severe showers and thunderstorms and high winds across the Deep South, Mid-Atlantic and Southeast on Saturday. Several tornadoes developed over southern Georgia and the Florida Panhandle, which destroyed homes and knocked sown power lines and large trees. In addition, hail and strong winds also occurred over parts of the Southeast.

A long cold front was the main weather producer in the country Friday. This front pulled moisture northward from the Gulf of Mexico, instigating widespread moderate to heavy rain along thunderstorms from eastern Texas through Mississippi. As the front moved into the Gulf of Mexico in the afternoon, it lost most of its moisture.

 

11^th-17^th…Record floodwaters inundated parts of southern Louisiana early Tuesday after intense rains caused flash flooding and prompted hundreds of rescues. Estimates by the National Weather Service put total rainfall at 12 to 18 inches across the region, with possible amounts of 20 or more inches in some areas. A flood warning has been issued until late Tuesday.

Floodwaters were cresting overnight for Bayou Vermilion at Carencro at

5.5 feet over flood stage and 12 inches above the record set in May 2004.

One of those involved 16 middle school students whose bus became stuck after more than 4 feet of water covered the road. Boats and dump trucks were used to reach the children and bring them to safety, Judice said.

The town of Carencro was among the hardest hit communities in Lafayette Parish, according to Capt. Craig Stansbury, who is also from the Parish Sheriff's Office. He noted there were reports of water as high as 8 feet on some roadways. Stansbury said fire department vehicles, tractors and conventional boats and airboats were being used to reach those stranded in homes and cars. The parish declared a state of emergency in the midst of the high water. A state of emergency was also declared in St. Landry Parish, where Government Administrative Director Jessie Bellard estimated that some 2,000 people had been affected. People were driving dump trucks to rescue residents who have flooding in their homes and can't get out. Bellard said several minor and major roads, including part of U.S. Highway 190, have experienced significant flooding. Maj. Ginny Higgins of the St. Martin Parish Sheriff's Office said flooding affected at least 15 to 20 roads Monday in that parish. Several people were safely rescued after being trapped in their vehicles, she said. A state of emergency has been declared for that parish, Higgins said. Stansbury, from Lafayette Parish, said residents knew Monday would be wet but didn't foresee the volume or intensity.

The entire nation saw significant weather on Tuesday, as the West saw rain and heavy snowfall, while the entire country east of the Rockies was in the midst of a very unusual warm spell.  The Northwest saw the greatest snowfall amounts with snow levels dropping to near sea level in many places. Snow descended into northern California as well, where a dusting was reported throughout the high elevations. Further south, in the lower elevations, heavy rain was reported. Close to an inch and a half of rainfall was reported throughout coastal northern California with amounts around an inch inland. In the Sierra Nevada mountains, temperatures remained warm, but snow levels were between 4000 and 5000 feet. Snow was expected to continue throughout the next several days.

Heavy rain made it as far south as the San Francisco Bay Area, but tapered off to the south. Rainfall was noted south through the Central Coast of the state, but light accumulations were reported.

 

18^th-24^th…Active weather began to ramp up across the Central U.S. on Monday as a cold front moved into the Plains and met ample moisture from the Gulf of Mexico. This combination kicked up significant rain and thunderstorms from northern Texas through eastern South Dakota and across parts of Arkansas and Missouri during the afternoon. These storms were expected to intensify through the rest of the afternoon. Areas of extreme western Arkansas, southeastern Oklahoma, and central/northeastern Texas remained at moderate risk of severe weather activity on Monday. The strongest of these storms were expected to produce damaging winds, large hail, and a few tornadoes. Elsewhere, light showers and thunderstorms formed in southern Wisconsin and parts of North Carolina, while above normal temperatures continued to dominate the eastern half of the nation.

In the West, a trough of low pressure supported more areas of rain and high elevation snow from parts of the Southwest through the Northern Intermountain West and Northern Rockies. Winter Weather Advisories and Winter Storm Warnings remained in effect for the mountains of western New Mexico, southeastern Arizona, central Utah, and much of Montana. A Blizzard Warning remained in effect for Havre and Chinook, Montana through the rest of the day in anticipation of significant snow accumulation and gusty winds. Total snow accumulations of 4 to 8 inches remained likely over the Plains with 10 to 20 inches in the mountains. Visibilities were expected to be below half a mile and near zero at times as gusty northwest winds of 25 to 40 mph with gusts to 60 mph create periods of blowing snow. Elsewhere, rain and light snow continued in the Pacific Northwest.

Severe weather moved over the Mississippi River Valley on Friday, as a low pressure system moved in from the Plains. A strong low pressure system advanced eastward from the Plains and pushed a cold front over the Mississippi River Valley and into the Eastern Valleys. This system pulled warm and moist air in from the Gulf of Mexico, which triggered moderate to heavy showers and thunderstorms. Some of these storms turned severe with tornadoes reported in southern Illinois and southeastern Missouri with multiple reports of large hail across the region. Heaviest rains developed along the southern side of this system, due to ample Gulf moisture. Rainfall totals surpassed 3 inches across southern Louisiana.

 

Jim G. Munley, jr.
http://www.jimmunleywx.com