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Area forecast discussion for western South Dakota and northeastern Wyoming 
National Weather Service Rapid City South Dakota
318 am MDT Sat Aug 29 2015

Short through Sunday night
issued at 317 am MDT Sat Aug 29 2015

Upper ridge axis will cross the northern plains today. Southwesterly flow will
develop over the County Warning Area bringing warmer and drier air today. Smoke
across the region is expected to clear up this morning as the flow
switches to the SW leaving sunny skies. Highs today will reach the
upper 80s to upper 90s. Breezy S/SW winds are expected today...with
the strongest winds reaching 15-20 miles per hour over NE Wyoming. Breezy winds will
continue tonight into Sunday. Upper trough will cross the Pacific northwest
into the northern rockies Sunday. Very warm air will remain over the County Warning Area
with highs reaching the 90s to just above 100. A cold front will
cross Montana sun and push into the northern plains Sun night. This will bring
a sl chance for storms late sun through the night. Relatively dry air
and fast moving boundary will keep quantitative precipitation forecast relatively light.

Long term...Monday through Friday
issued at 317 am MDT Sat Aug 29 2015

The negative height anomaly over the Pacific northwest will remain nearly
stationary through the period with a series of upper troughs
developing then shifting off to the northeast. Extended models are
in relative agreement showing phasing of the northwest Pacific upper trough
with a strong northern Canadian upper trough likely leading toward
the ridge breaking down by next weekend. Above average temperatures will
persist through most of the period...with mainly dry conds. Northwest Pacific
upper trough will move east by the end of the week with cooler
weather looking more likely next weekend with increasing chances
for rain.


Aviation...for the 12z tafs through 12z Sunday morning
issued at 317 am MDT Sat Aug 29 2015

Mainly VFR conds with areas of MVFR visible possible in smoke from
western wildfires.


Fire weather...
issued at 317 am MDT Sat Aug 29 2015
warmer and drier weather will push into the area today and Sunday.
Temperatures across northeast Wyoming and western South Dakota
plains will rise well into the 90s...with relative humidity across
portions of the northeast Wyoming plains dropping to below 15%.
Southwest winds will increase to 15 to 20 miles per hour with gusts to 25 or
higher. Will issue red flag warning for this afternoon/early evening. Gusty
winds and low relative humidity are again possible will continue with
Fire Weather Watch. A cold front will cross the area Sunday
night with more seasonable temperatures are expected Monday.

Unr watches/warnings/advisories...
South Dakota...none. flag warning from noon today to 8 PM MDT this evening for

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



Short term...13
long term...10
fire weather...13

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