Area Forecast Discussion
Issued by NWS Sioux Falls, SD

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KFSD 252029

Area Forecast Discussion
National Weather Service Sioux Falls SD
329 PM CDT Wed Apr 25 2018

.SHORT TERM...(This evening through Thursday)
Issued at 323 PM CDT Wed Apr 25 2018

Relatively quiet conditions with light variable winds will continue
through late this evening as the surface high moves southeast into
NE/IA. Clouds will gradually increase from northwest to southeast
late tonight as a frontal boundary quickly slides southeast through
the area early in the morning to around early afternoon. Gusty
northerly winds of 35-40 mph are expected behind the front, with
sustained winds of 15 to 25 mph. Could see some skittish/spotty
showers as this fast-moving front moves through, but with limited
moisture aloft little to none accumulations are expected. With
clouds and north winds in place, highs will only reach the upper
50s in southwest Minnesota and the low 60s elsewhere.

.LONG TERM...(Thursday night through Wednesday)
Issued at 323 PM CDT Wed Apr 25 2018

Mostly dry and warm weather conditions are expected from Friday into
the beginning of next week as a strong upper level ridge centered
over the western CONUS, moves eastward into the Central Plains. With
this omega block pattern, northwest flow aloft and more southerly
flow at surface will bring temperatures warmer than average. Friday
and Saturday will generally stay in the 60s to near 70. Sunday and
Monday look even warmer with highs in the mid 70s to near 80 in
south-central South Dakota. Some locations could reach the 80
degree mark by Sun/Mon. The main concern during this period will
be fire weather conditions across the region as low dewpoint
values and relative humidity in the 20 to 40 percent will be
possible, mainly in south-central South Dakota.

Models continue to bring unsettled conditions for next week as the
strong upper ridge breaks down by Monday, changing the synoptic flow
pattern across the region. Although latest model runs have shown
better agreement in terms of flow pattern aloft, uncertainty still
remains in timing and strength. The GFS and the Canadian continue to
bring the strong upper low over the Northern Plains by Sunday night
into Monday while the ECMWF suggests a slower and weaker trough. At
this time, have kept chances of showers and thunderstorms Sunday
night into Monday, then re-developing again by Tuesday. With warm
temperatures, strong low-level flow and instability, strong to
severe storms will be possible next week. Spring is here!


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1234 PM CDT Wed Apr 25 2018

VFR conditions will prevail through the TAF period, although there
will be a small chance for an MVFR ceiling near the timing of a
strong frontal passage starting around 10z at KHON, 13z at KFSD
and 15z for KSUX. May also be a few light showers, but conditions
not expected to stray from VFR visibilities. Northerly winds
behind the front on Thursday will gust to 25 to 35 knots.




AVIATION...Chapman is the U.S. government's official web portal to all federal, state and local government web resources and services.