Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion for western South Dakota and northeastern Wyoming 
National Weather Service Rapid City South Dakota
239 am MDT Monday Mar 30 2015

Short through Tuesday night
issued at 240 am MDT Monday Mar 30 2015

Current surface map places weak trough across the western Dakotas.
Warm and dry the next couple of days...with fire weather the main

Upper level ridge builds across the northern plains today...and
remain across the area for Tuesday. Temperatures near high end of
guidance. Gusty northwest winds across the South Dakota plains
today...with gusty southwest winds across northeast Wyoming for

Long term...Wednesday through Sunday
issued at 240 am MDT Monday Mar 30 2015

A strong shortwave trough will cross the northern
plains on Wednesday...but moisture is very limited...and little
precipitation is expected. A surface cold front will accompany this
upper disturbance...bringing slightly cooler temperatures and gusty
northwest winds to the area. A secondary trough will cross the
Central Plains towards the end of the week. Model solutions now
showing the best band of rain/snow south of the forecast
area...across southern Wyoming...northern Colorado...and Nebraska.
Highs for the end of the week will


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 240 am MDT Monday Mar 30 2015

VFR conditions are expected through Tuesday morning.


Fire weather...
issued at 240 am MDT Monday Mar 30 2015

Deep mixing will allow gusty northwest winds to develop on the
western South Dakota plains north and east of the Black Hills.
With minimum relative humidity of 15-20 percent and 20-30 miles per hour
winds...grassland fire danger index is in the extreme category.
Will issue red flag warning for South Dakota fire zones

Warmer temperatures for Tuesday...with minimum relative humidity
of 10 to 15 percent. Gusty southwest winds will develop across northeast
Wyoming. With combination of very low humidity and gusty
winds...will issue red flag watch Tuesday for Wyoming fire zones
259-297-298. Grassland fire danger index will be in the extreme
category for western and south central South Dakota on Tuesday.


Unr watches/warnings/advisories...
South flag warning from 11 am this morning to 7 PM MDT this
evening for sdz261-264>266.

Wyoming...Fire Weather Watch from Tuesday afternoon through Tuesday
evening for wyz259-297-298.



Short term...7
long term...15
fire weather...7

National Weather Service Glossary of Abbreviations