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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
650 PM CDT sun Jul 5 2015

Short term...(this evening through monday)
issued at 252 PM CDT sun Jul 5 2015

There is still an easy to recognize fairly strong severe storm
potential tonight with Storm Prediction Center depiction of potential and general
timing looking good. The problem lies in the
specifics...especially the initial development of storms. Some of
the short range high resolution models are depicting fairly early
development ahead of the cold front. In the case of the
operational hrrr this looks to be done too early and too far
southeast. However other models are more moderate yet still
indicate some development fairly early ahead of the front...which
by the way for the time being has progressed somewhat faster
toward the area than models have been depicting. I would expect a
slowdown due to wave action which probably also shows up in the
development of the low level jet depicted strongly on the models.
In short...still expect the bulk of the storms and the severe
threat from late evening on...after midnight southeast...but we
will watch for possible scattered development as early as the end
of the afternoon.

As mentioned...the severe potential is still there for scattered
winds and hail early and especially winds late tonight. Will
continue to include the hail/wind/heavy rain mention in the grids
along with the high probability of precipitation. As for the heavy rain...currently
anticipated quantitative precipitation forecast and current ffg do not show a need for a Flash Flood
Watch. The northeast appears to have the best potential for heavy
rain but that could change depending on how the convection behaves.

The front will begin to move through the area this evening and reach
the southeast corner Monday morning. Cooler air with the northerly
winds will lower temperatures to the lower 60s northwest...with 70
or so lows southeast.

Lingering showers and storms will end from the northwest Monday and
clouds will decrease. By late afternoon the cool and dry regime will
have taken over and the last of the showers in northwest Iowa should
have ended. The northerly winds will take hold and get marginally
breezy...while temperatures hang in the 70s and skies brighten from
the northwest.

Long term...(monday night through sunday)
issued at 252 PM CDT sun Jul 5 2015

The first half of the medium range forecast will remain cool and dry
through Wednesday as high pressure settles in across the Great
Lakes. Cool easterly flow will keep temperatures in the 70s in most
locations...almost 10 degrees below normal for this time of the
year. Have lowered low temperatures a few degrees.

By Wednesday and Thursday...models suggest a weak wave passing
through the middle-level flow. The strong influence of dry surface high
pressure should keep probability of precipitation at a minimum.

By the end of the week and into next weekend...flow aloft should
begin to turn more southwesterly...typically indicative of warming
temperatures...increasing humidity and the potential return of low-
end precipitation chances by next weekend. Several waves of energy
will move through the flow...but the exact track of these waves in
doubt. As far as temperatures are concerned...forecast holds
readings above normal by the weekend...and we may be pushing 90s in
many areas by early next week.


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 650 PM CDT sun Jul 5 2015

Threat of convection will expand south and east across the forecast
area through the first half of the forecast period. Periods MVFR to
locally IFR conditions along with gusty winds will accompany some of
the storms. Strongest cluster of storms expected to remain south of
khon...but could impact kfsd and/or ksux with strong winds after
06z. Tamer conditions will prevail after 06/12z...though period of
MVFR ceilings and areas of light rain will likely linger through the
morning. VFR conditions expected to become more prevalent after


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


Short term...
long term...dux

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