Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus63 kfsd 182334 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
634 PM CDT sun Mar 18 2018

Short term...(this evening through monday)
issued at 331 PM CDT sun Mar 18 2018

Persistent low cloud event continues across the area with widespread
stratus. With deep saturation in the near surface layer, could see
areas of fog and drizzle. There is a band of warm air advection
that lifts northeast across the area. Could see some light
precipitation across central South Dakota, but further to the east
will be increasingly difficult to get precipitation to the surface
as there is a very pronounced dry layer between 600-800 mb.

Clouds will continue to remain across the area on Monday as upper
level low moves across the Central Plains. With extensive cloud
cover like today, have kept forecast highs towards the cooler side
of guidance.

Long term...(monday night through sunday)
issued at 331 PM CDT sun Mar 18 2018

Monday night a series of intensifying waves move from west to east
leading to precipitation across the area. Not a lot to focus on in
terms of frontogenesis, but rather broad area of lift ahead of the
waves will lead to precipitation. With precipitation changing from
rain to snow Monday night, and then possibly transitioning back to
rain Tuesday morning, snow amounts are tricky, but overall, think it
will be relatively light.

A gradual warming trend is expected through Thursday ahead of the
next weather maker next weekend. Fairly high model agreement that
the leading wave in a disorganized upper level trough will move
through the area on Friday morning. This generally looks to be
rain, especially across the southern half of the forecast area.
Temperatures for this weekend are all over the place. There is a
fairly strong signal in the men guidance to err colder, as the
operational run of the GFS appears to be a warm outlier. With that
said, it is not alone however, as the Canadian is mild through
Saturday. The European model (ecmwf) has been consistently much cooler, suggesting
more snow than rain. With the models suggesting low confidence,
have left the blend as is for now.


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 632 PM CDT sun Mar 18 2018

MVFR stratus continues through the taf period with reduction to
IFR expected at Hon and briefly at sux. Some patchy fog is once
again possible at all taf sites, in particular Hon and sux. Rain
changing over to snow begins to approach from the west by the end
of the taf period.


Fsd watches/warnings/advisories...
South Dakota...none.

National Weather Service Glossary of Abbreviations