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000
FXUS63 KUNR 181716
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1116 AM MDT Wed Apr 18 2018

.DISCUSSION...(Today Through Tuesday)
Issued at 330 AM MDT Wed Apr 18 2018

Current surface analysis shows low pressure centered over
northeast KS, with an inverted trough extending back to the
northwest to low pressure over southern SK. Upper level analysis
shows developing low pressure now over southeast SD. Regional
radars show main areas of snow east and southeast of the forecast
area, but a band of light to moderate snow has set up along the
inverted trough from parts of western SD to central SD. The most
significant snow over the forecast area at this time is in Tripp
County. Some areas of light snow are noted further west to the
Dupree, Philip and Mission areas. A few rain and snow showers have
also developed across the Black Hills area. Temps are generally
in the 30s with north to northwest winds mostly at 5 to 15 mph.

Conditions will gradually improve through the morning as the system
moves away from the region. Additional snow and light accumulations
can be expected across parts of central SD early this morning, with
snow tapering off toward mid to late morning. A few rain showers are
possible elsewhere across western SD toward the afternoon hours,
especially northwest SD. Highs will mostly be in the mid 40s to
lower 50s with brisk northwesterly winds across much of the plains.

A ridge will build across the area late today and tonight, moving
east of the area on Thursday. It will be a bit warmer on Thursday,
but still slightly below average in most areas. The next storm
system will be tracking across the western US on Thursday and into
the Plains later Friday through Saturday. The track of the main low
pressure system is still projected to go well south of the area.
However, upper level energy moving northeast ahead of the low could
bring rainfall to parts of the area, especially southern SD, late
Thursday night through Friday night.

The weekend generally looks dry at this point, with any lingering
rainfall exiting Saturday morning. A ridge of warmer air aloft
should bring more pleasant temperatures, especially by Sunday, with
highs in the 50s and 60s. Unsettled weather will likely return early
next week as a cold front crosses the Northern Plains. There looks
to be a good chance for rain showers and some overnight snow showers
Monday into Tuesday.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Thursday)
Issued At 1110 AM MDT Wed Apr 18 2018

VFR conditions are expected across the area through Thursday
morning. The exception will be across far south central SD where
IFR/LIFR conditions with snow will persist through late
afternoon...improving to VFR this evening.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...None.
WY...None.
&&

$$

DISCUSSION...26
AVIATION...15