* Percent of country in moderate drought or worse at 64.58 pct
* Conditions most severe in High Plains, Nebraska hit hardest
* Rainfall brings some relief to Texas, southern Oklahoma
Oct 4 (Reuters) - Drought conditions in the United States eased slightly over the last week, though dry soils and water shortages persisted across wide swaths of important farm states, particularly Nebraska, a key corn and cattle state.
Roughly 64.58 percent of the contiguous United States was under at least "moderate" drought as of Oct. 2, down from 65.45 percent a week earlier, according to the Drought Monitor, a weekly compilation of data gathered by federal and academic scientists issued Thursday.
The portion of the United States under "exceptional" drought - the most dire classification - fell to 6.07 percent, down from 6.12 percent a week earlier.
Conditions remained poor in the High Plains where severe or worse drought levels covered 87.51 percent of the region, up from 83.80 percent the prior week. Nearly 28 percent of the region, which includes Nebraska, Kansas and Colorado, was in the worst level of drought, dubbed "exceptional," up from 24.35 percent a week earlier.
Nebraska suffered the most as drought levels expanded fairly dramatically in the last week. Exceptional drought levels now cover 77.61 percent of the state, up from 73.25 percent a week earlier, according to the Drought Monitor.
In Kansas, a top wheat growing state where farmers are now trying to plant their next winter wheat crop, conditions improved slightly as the percentage of the state in exceptional drought dropped to 44.73 percent from 51.04 percent.
Oklahoma saw much greater improvement as the portion of that state suffering from exceptional drought dropped to 28.21 percent from 42.09 percent, according to the data.
Both Oklahoma and Texas benefitted from rainfall that brought 2 inches or more of moisture to parched soils.
The western United States, including Colorado, Nevada, Wyoming and New Mexico, saw exceptional drought creep higher in some areas. But overall drought was easing with 43.47 percent of the region in severe or worse drought, down from 43.65 percent.
Mostly dry conditions are forecast for the next several days, according to the report. (Reporting by Carey Gillam in Kansas City; editing by Jim Marshall)