Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 222254

Area Forecast Discussion
National Weather Service Sioux Falls SD
554 PM CDT WED JUN 22 2016

.SHORT TERM...(This evening through Thursday)
Issued at 310 PM CDT Wed Jun 22 2016

High pressure settling in tonight will allow for decreasing winds
and drier air, leading to cooler morning low temperatures. The only
real forecast challenge overnight will be the stratus field across
North Dakota and whether or not that will work into the area. Cannot
completely rule it out but suspect that much of it is diurnally
driven so not expecting widespread ceilings. Aiming for low
temperatures from the mid 50s in the mid James Valley to the lower
60s around Sioux City and Storm Lake.

Thursday will prove to be a little cooler and a little drier with
light winds, so a very pleasant summer day. Highs mainly in the
upper 70s to mid 80s with some scattered cumulus cloud cover.

.LONG TERM...(Thursday night through Wednesday)
Issued at 310 PM CDT Wed Jun 22 2016

Thursday night will start mostly clear, and skies should stay that
way over most of the area during the night. Near the end of the
night, a band of sharply increasing moisture and warm advection,
mainly aloft, is progged by models to approach the eastern Missouri
River area, roughly from Yankton east. While there does not appear
to be much of a mechanism to initiate convection, with the low level
jet mainly to the west, I would not be surprised to see a few
elevated storms develop around daybreak or a bit after. With
parameters not too conclusive, will settle for a slight chance
Friday morning over the southern part of northwest Iowa. As this
gradient pushes northeast, any elevated storms should diurnally
dissipate, and will not include any storms over the area for Friday
afternoon. thursday night lows will be int he 60s, and Friday highs
in the upper 80s to lower 90s.

On Saturday a cold front will move into the area from the west,
ahead of support provided by an upper low moving east across
southern Canada. Ahead of this, storm chances Friday night are a bit
complicated, with a strong low level jet developing over the eastern
forecast area as the front and upper system approach from the west.
For now, will keep a mention of storms late west, and not mention
east. since mid level winds become very weak in the east. We will
have to revisit this possibility on the next forecast cycle or two.
Timing of the front and storms saturday is also a bit uncertain, and
will keep a very broad chance with the system coming through
Saturday. with storms expected to decrease and end to the east
Saturday night. Saturday should be warm with highs in the mid to
upper 80s.

Sunday through Tuesday will show a modest cooling trend as the
upper low moves east, and weak short waves break down the Rockies
upper ridge a little more. Highs are expected to be in the mid 70s
to lower 80s for Tuesday. A few showers or storms will be possible
Monday night and Tuesday with support being provided by one of the
above mentioned waves. Will go with the extended guidance on
continuing a slight chance for Wednesday as well, with temperatures
again on the mild side.


.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 549 PM CDT Wed Jun 22 2016

Mainly VFR conditions expected through the TAF period. The one
exception may be MVFR stratus situated across North Dakota this
evening. Some models are hinting that this could track southward
tonight, pushing into areas north of Interstate 90 after 10z.
Confidence still low on this scenario so did not include in TAFs.


.FSD Watches/Warnings/Advisories...


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