Today, were are focused on the Upper Mississippi Valley for severe convective development.  A potent, negatively-tilted shortwave trough is moving quickly across the north-central U.S.   Strong deep-layer shear associated with the trough should combine with moderate (to strong) instability and deep moisture to produce severe convection, including supercells.  It is uncertain, however, whether sufficient heating can occur in the wake of a late-morning mesoscale convective system across eastern Minnesota and western Wisconsin.  If destabilization can occur in the vicinity of the residual outflow boundary, tornadoes will be possible.

A secondary area of interest is in south-central Nebraska, where the surface front curves to the southwest.  In this area, the moisture is both deep and quality; the instability , strong to extreme; and the winds at the surface should back, augmenting — to some extent — the marginal wind shear.  That said, severe hail and winds should be the primary threats.

We will start operations in the Minneapolis (MN), Sioux Falls (SD), and Hastings (NE) county warning areas, with an eye toward the  Duluth (MN) CWA — should destabilization occur.

-G. Garfield, Week 5 Coordinator

Today, we are focused on two areas for severe convective development.  The first is in the southern High Plains, where rich, deep moisture resides beneath a very potent elevated mixed later.  As surface temperatures warm, strong to extreme instability is expected to develop over west Texas into eastern New Mexico.  However, kinematic profiles are marginally favorable for the development of organized convection.  Nevertheless, the degree of available potential energy suggests that this area should be watched for severe weather.

The second area is located in the central and northern Plains.  An upper-tropospheric trough is emerging onto the Plains this afternoon, and resultant pressure falls will create a kinematic environment favorable for the development of organized storms.  However, the moisture is limited and the lapse rates are only moderate where moisture quality is the greatest.  Nevertheless, we will monitor this area for convective development.

-G. Garfield, Week 5 Coordinator