Monday, July 13th 2009 Weather Outlook

13 07 2009

Monday’s Weather Outlook; West/Plains System, Mississippi Valley/Southeast System

1:45AM

On Monday, a system will continue to affect the Southeast and Mississippi valley, while a system moves toward the Plains. Showers and storms will be likely across portions of the Southeast and Mississippi Valley, as a frontal boundary continues to wark across the area. Across the Carolinas down into Alabama; CAPE values will be around 2500 J/Kg, LI’s of -6 and Effective Bulk Shear values up to 35KT. This will aid in the development of some severe storms. Limited forcing will limit the coverage of the severe potential, which will preclude a slight risk from being issued. Further west in the Mid and Southern Mississippi Valley, an MCS may be ongoing in the Morning across portions of Missouri and Arkansas. Some storms may be severe. This complex will continue to push southeast into the Afternoon as it weakens. In the wake of this complex, CAPE values will be around 4500 j/KG, LI’s of -10 and Effective Bulk shear values of 25-50KT There is the potential for a cluster of storms to develop in portions of Oklahoma, Missouri and Arkansas during the late Afternoon or Evening. If this occurs, the complex may grow upsclae into an MCS asi it continues southeast through the Night with a severe potential. IIf either the Morning MCS is sustained or the Evening complex forms, an upgrade to a slight risk may be needed for portions of the Mississippi Valley. The main threats from any storms that become severe will be damaging winds, hail and an isolated tornado. In the West, a system will push eastward towards the Plains. There is a slight risk for severe storms in portions of Montana, Wyoming, North Dakota, South Dakota, Nebraska, Colorado and Kansas. CAPE values will be around 3500 J/Kg, LI’s of -8 and Effective Bulk Shear values of 35-65KT. This along with the system in the area, will help storms become severe. Severe storms will develop int he Afternoon along the Front Range, from Montana down into Colorado. These storms will push eastward into the Evening. Storms may grow upscale into one or two MCS’s across portions of North dakota, South Dakota and Nebraska During the Evening. These complexs will continue eastward overnight with a severe threat. The main threats from the severe storms will be damaging winds, ahila and a few tornadoes. Across portiosn of the Inter-Mountain west, a few storms may become severe, with the main threats being haila nd damaging winds. Below is the severe weather outlook for Monday.

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Sunday, July 12th 2009 Weather Outlook

13 07 2009

Sunday’s Weather Outlook; Plains/Mississippi Valley/Southeast System, West System

12:00PM

On Sunday, a system will continue to affect the Plains into the Southeast, while a new system moves into the West. Showers and storms will be likely over portions of the Southeast, Mississippi valley and Plains, associated with a frontal boundary over the area. There is a slight risk for severe storms in portions of Maryland, Virginia, North Carolina, South Carolina, Kentucky, Georiga, Tennesse, Alabama, Missouri, Illinois, Iowa, Kansas, Nebraska, Wyoming, Colorado and South Dakota. Along the front in the Mid-Atlantic; CAPE valeus will be around 3500 j/Kg, LI’s of -8 and Effective Bulk Shear values of 25-55KT. severe sotrms will develop in the Afternoon from Maryland down into Virginia. These storms will push southeast into the Evening, before weakening as diurnal cooling sets in. Across the Tennesse Valley into the Sentral Plains; Two MCS’s will be ongoing across portions of the Southern Midwest and Central Plains. One will be moving southeast through South Dakota, Iowa and Nebraska. Some storms may be severe with this complex. This complex will weaken as it pushes into stable air during the Afternoon. The second complex will be located over portions of Kansas, Nebraska and Missouri. This complex will race east-southeast through the day. Some storms may be severe with the complex in the Morning, severe storms will be likely as it heads into unstable air in the Tennesse Vally during the Afternoon and Evening. CAPE values will be around 4000 J/KG, LI’s of -8 and Effective Bulk Shear values of 25-55Kt in the Tennesse Valley will aid in the severe potential. Along the Front Range from Wyoming down into Colorado; CAPE values will be around 3500 J/Kg, LI’s of -7 and Effective Bulk Shear valeus of 25-55KT. Severe sotrms will develop in the Afternoon off of the higher terrain of Colorado and Wyoming. These storms will push eastward into the Evening. Storms may grow upscale into an MCS during the Evening and continue eastward overnight with a severe threat. The main threats from the severe sotrm sill be damaging winds, hail and an isolated tornado. Across the West, a new system will move into the region, bringing the chance of showers and sotrms to the region. Some storms may become severe over portions of the Northwest. CAPE values around 2000 J/Kg, LI’s of -6 and Effective Bulk Shear values of 30-70KT. This instibility will aid in the severe potential. Limited coveragw will preclude a slight risk from being issued. The main threats from any storms that become severe will eb hail and damaging winds. Below is the severe weather outlook for Sunday.

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