NATIONAL STORM SUMMARY

 

MARCH 2013

 

1^st-9^th…Precipitation diminished in the East on Friday, while a strong winter storm moved across the Southwest. A low pressure system moved over southern California and into the Desert Southwest and brought abundant moisture in from the Pacific Ocean. This triggered heavy rain showers and high elevation snow showers across the southern half of California, far southern Nevada, most of Arizona, and into Utah, Colorado, and New Mexico. Heaviest snowfall was reported in Forest Lakes, Arizona with a mid-day total of 11 inches, while rainfall totals ranged from 1 to 2 inches across southern California and Arizona. As this system advanced northeastward throughout the day, the storm pushed moisture into the Great Basin as well as the Central and Southern Rockies, and produced increasingly heavy precipitation. Winter storm advisories have been issued from the Southwest through the Upper Midwest. At the same time, the leading edge of this system pulled moisture in from the Gulf of Mexico, which allowed for scattered showers and thunderstorms to pop up across the Southern and Central Plains. These storms have not yet turned severe, but there was a chance of severe thunderstorm development in northern Texas. In the East, a strong low pressure system slowly moved offshore, allowing for heavy rain and heavy snow showers to taper off for the coast of New England from New Jersey through southern Maine.

 

17^th-23^rd…A strong Pacific storm moved through the Northwest and California Wednesday, renewing rain and high elevation snow from Washington through Northern California. This storm was relatively warm, thus snow was reserved for the higher elevations of the Sierra Nevadas of California and Cascades of the Northwest. This rain and snow was very welcomed along the West Coast, especially in California where many areas have received much less rainfall that normal for this past Winter. In addition to the precipitation, Wind Advisories warned of wind gusting to 65 mph, making travel dangerous at the higher elevations.

 

24^th-31^st…Snow spread from the Rockies and through the Plains on Friday, while showers and thunderstorms developed in the South. As a low pressure system moved off the Rockies and through the Plains, flow from the south pulled moisture in from the Gulf of Mexico. This allowed for scattered showers and thunderstorms to develop from the Southern Plains and across the Lower Mississippi River Valley. Periods of heavy rainfall developed in these areas with rainfall totals over 1 inch. The heaviest rainfall was reported at Monticello, Arkansas with a mid-day rainfall total of 1.68 inches. Meanwhile, cooler temperatures along the northern side of this system created snow showers across the Northern and Central Plains. Snowfall totals range from 3 to 5 inches across the Dakotas. At the same time, the back side of this system allowed for periods of heavy snow showers to persist across the Rockies and High Plains. Winter weather advisories remained in effect from Colorado through western Nebraska and Kansas as up to 7 inches were expected by Friday evening.

 

Snow continued across portions of the Midwest and picked up along the Mid-Atlantic and Northeast Coasts on Monday as the strong storm of the East lift northward. In the Midwest, generally moderate scattered snow showers continued from in the Ohio Valley and parts of the eastern Tennessee Valley on Monday as an area of low pressure over Kentucky lifted northeastward over the Central Appalachians. Sufficient moisture and chilly temperatures over the region translated into possible snow storm conditions in these areas through the afternoon and evening. Thus far, storm totals of up to 4 to 10 inches have been reported in the impacted areas of the Midwest with locally higher amounts of up to 18.5 inches reported in southern Illinois. In addition to snow, gusty north and northeast winds cause areas of blowing snow, lowered visibilities, and potentially dangerous driving conditions. Meanwhile, the other portion of this late season storm lifted northward through the western Atlantic Ocean, remaining just offshore of the East Coast, through the morning and became positioned just east of Delaware this afternoon. This low strengthened and allowed strong winds to spread across the Mid-Atlantic and New England Coast with plenty of moisture. Areas of rain and snow developed along the immediate coastline, while cold temperatures supported snow showers across inland areas. More accumulating snow blanketed the higher elevations of the central Appalachians. Snow accumulations of 6 to 8 inches were expected at elevations above 1,500 feet, while 4 to 6 inches of snow were anticipated elsewhere in the mountains.

Thunderstorm activity spread across the southern Plains and Southeast on Friday, while widespread rain and snow spread from the Northern Rockies into the Northern Plains. A frontal boundary extended from the Southern Plains through the Tennessee Valley. Moisture from the Gulf of Mexico brought energy into this system, and allowed for up scattered showers and thunderstorms to develop from northern Texas, through Arkansas, and into the Tennessee Valley. Some of these storms turned severe with large hail, strong winds, and periods of heavy rainfall. Heaviest rainfall was reported at Fort Leonard Wood, Missouri with a mid-day total of 1.09 inches of rain. There have been multiple reports of 1 inch in diameter hail across central Oklahoma.

 

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