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Area forecast discussion for western South Dakota and northeastern Wyoming 
National Weather Service Rapid City South Dakota
531 am MDT Monday Jul 28 2014

Short through Tuesday night
issued at 229 am MDT Monday Jul 28 2014

Upper ridge over The Rockies will sharpen as trough over eastern US
deepens and another trough approaches West Coast. Series of short
wave will cross ridge onto the plains. First wave over the Great
Basin will cross Wyoming today and move into NE. Expect isolated
thunderstorms over northeastern Wyoming and southwestern South Dakota this
afternoon and tonight as Theta-E ridge builds into eastern
Wyoming...and cape values increase to 500 j/kg with very little cin.
Precipitation potential remains over the same area Tuesday as Lee
trough develops as inverted trough forms along Front Range and extends
into eastern Wyoming. Dry...stable air will remain over rest of forecast

Surface ridge continues to build south into the northern plains with
ridge axis remaining north-S over central Dakotas-NE. Light and
variable winds over western South Dakota will gradually become southeast...
but cold air advection will continue through Tuesday. Kept maximum temperatures at
or below persistence. Min temperatures will be a few degrees
warmer as winds and cloud cover increase.


Long term...Wednesday through Sunday
issued at 229 am MDT Monday Jul 28 2014

A strong high pressure ridge over western North America and a strong
full lattitude trough over the eastern part of the continent will
continue to dominate the large scale maps from midweek through early
next week. A mostly dry northwest flow will persist over the northern High
Plains. Weak embedded impulses are forecast to trigger a few showers
over the higher terrain of the Black Hills and northeast Wyoming
Friday and Saturday. However only minimal moisture will be available
for this activity and strong storms are not expected at this time.
Temperatures will remain near of slightly below seasonal


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 527 am MDT Monday Jul 28 2014

VFR conditions are generally expected through the forecast
period. A few thundershowers may form over southwest South Dakota
and northeast Wyoming late this evening. Local MVFR conditions
are possible in precipitation.


Unr watches/warnings/advisories...
South Dakota...none.


Short term...55
long term...CArpenter

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