Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 110453

Area Forecast Discussion
National Weather Service Sioux Falls SD
1053 PM CST Sat Mar 10 2018

.SHORT TERM...(This evening through Sunday)
Issued at 327 PM CST Sat Mar 10 2018

Things look on track for some light snow tonight as a decent little
wave approaches from the northwest. While the main impulse will dig
to our south, we`ll receive enough PV advection for some decent lift
through midday Sunday. As we move closer to Spring, precipitation
type is becoming a challenge at times. Luckily, by this evening the
warm nose aloft will have eroded and the vast majority of the
precipitation will fall first as rain before switching to snow
rather early during the event. Snow amounts remain a challenge with
spotty areas of frontogenesis and negative EPV*. Thermodynamic
profiles generally reflect this with occasional scant elevated CAPE
seen. Thinking that a broad light snow with occasional showery
enhancements will be the final result. With no real way to pinpoint
who gets the brief snow shower, have put out a broad one half to 2
inches across the CWA with highest amounts around MDS-BKX-PQN where
a band of light snow is ongoing and around Gregory/Charles Mix/Brule
counties, where the wave pivots and focuses lift for a bit longer
period of time. Tonight will also see some fog along the front in
our east where winds are minimized.

.LONG TERM...(Sunday night through Saturday)
Issued at 327 PM CST Sat Mar 10 2018

Uneventful weather will dominate the extended forecast. Northwest
flow takes over starting Sunday, clearing out much of the moisture
aloft. A disturbance in the flow will translate southeastward Monday
night, but it will be far enough to our southwest and the mid levels
will be too dry for any impact.

Ridging aloft begins to build in by the middle of the week. At the
same time, closed low over the Pacific Northwest will begin to drive
some subtle lee pressure falls to our west, allowing some gradient
southerly winds to set up across the northern Plains. Our warmest
temperatures yet this year may be the result. Only thing tempering
enthusiasm for now is that operational model runs are a bit warmer
than their ensemble envelopes.

Western low will continue to edge eastward as the week goes on,
eventually bringing back chances for active weather by late
Friday. Quite a bit of uncertainty at this time as the global
models all seem to show rather distinct evolutions. Just know the
nice weather won`t last forever.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1053 PM CST Sat Mar 10 2018

Widespread MVFR-IFR conditions will prevail across the region
through early afternoon Sunday. Gradual improvement from west to
east is expected after 21Z Sunday, with VFR conditions becoming
prevalent across our SD and MN counties by the end of this TAF
period. MVFR ceilings may hang on across much of northwest IA,
including at KSUX, through 12/06Z.




SHORT TERM...Ferguson
LONG TERM...Ferguson
AVIATION...JH is the U.S. government's official web portal to all federal, state and local government web resources and services.