Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 162345

National Weather Service Sioux Falls SD
645 PM CDT Mon May 16 2022

.SHORT TERM...(This Evening through Tuesday)
Issued at 316 PM CDT Mon May 16 2022

Weak surface ridging centered over eastern KS and western MO this
afternoon will shift off to the southeast this evening, while a
surface high over southern Canada pushes into the Northern Plains.
This will drive a back door cold front through our area during the
evening, which will become stationary along the southern edges of
our CWA overnight. CAMs continue to indicate shower and isolated
thunderstorm development toward 06Z tonight, focused north of
Interstate 90 with increasing mid level theta e advection as a low
level jet strengthens overnight and a weak midlevel shortwave tracks
through the region. Not expecting any strong storms overnight -
with any significant instability well to our south - but with a
few hundredths J/KG of elevated CAPE in place, cannot rule out
some isolated thunder. It will be a milder night with lows in the

For Tuesday, CAMS indicate that a few showers and thunderstorms will
remain possible through the day, though stronger instability remains
south of our area for the first half of the day. By afternoon,
stronger instability begins to nudge northward into the the MO River
corridor in the vicinity of a warm front lying across the region as
a surface low rides through Nebraska during the afternoon and
evening. Because of that, there is a risk of strong to severe storms
over this area during the evening if convection can develop, though
RAP analysis suggests that the better 0-6 km bulk shear will be
displaced from the better instability, so a marginal convective risk
as issued by SPC still seems appropriate. With the front sitting
along our southern border, there will be a wide range of
temperatures for Tuesday with highs in the lower to mid 60s over
southwestern MN to mid and upper 70s south of Interstate 90.

.LONG TERM...(Tuesday Night through Monday)
Issued at 316 PM CDT Mon May 16 2022

Any showers and thunderstorms move off to the east by Wednesday,
leading to a dry and slightly warmer day with highs in the mid 70s
to near 80. A cold front slides through the area by afternoon, and
the GFS continues to produce thunderstorms over south central SD
during the evening, though it is the only model that does so, thus
the forecast remains dry.

By Thursday a warm front lifts northward across the area as low
pressure deepens over central SD, then pushes a cold front through
the area on Thursday night as the low moves to the east. With
increasing instability in the warm sector and strong bulk shear, this
will be our next chance of strong to severe storms as outlined in
the SPC day 4 convective outlook.

Big changes are in store for the end of the week as an upper level
trough settles into the region on Friday and Saturday. This will
bring much cooler temperatures as highs fall back into the 50s to
lower 60s with lows in the 30s to lower 40s. Although there could be
a couple shots of precipitation during that time frame, model
differences yield a dry forecast for the end of the week.


.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 644 PM CDT Mon May 16 2022

VFR conditions expected through the morning hours on Tuesday. Light
scattered showers and isolated thunderstorms will be possible after
around midnight throughout the overnight period, with most of the
activity remaining north of I-90. Another round of showers are
likely by the late morning hours into the afternoon, with MVFR cigs
likely developing for areas north of I-90.




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