000
FXUS63 KFSD 122024
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
324 PM CDT Fri Apr 12 2024

.KEY MESSAGES...

- Unseasonably warm weather Saturday through Monday brings highs
  in the 70s and 80s, 20 to 30 degrees above normal for mid
  April. This heat combines with breezy conditions on Saturday
  and Monday to bring periods of elevated fire danger.

- A Fire Weather Watch has been issued for portions of our area
 Saturday.

- A period of wet weather is expected Monday evening through
  Tuesday with a moderate to high (50-80%) chance of at least a
  half inch of rain across the region.

&&

.DISCUSSION...
Issued at 323 PM CDT Fri Apr 12 2024

CURRENT/TONIGHT: Sunny skies, light winds, and highs in the upper
50s to 60s have made for quite a pleasant day across the region.
Expect much of the same through the late afternoon and evening, as
wind direction gradually becomes more south/southeasterly. Should
see gusts pick up in areas west of I-29 after midnight, with values
ranging between 20 to 25 MPH. Lows during this time look to remain
fairly mild, as temperatures only fall into the 40s.

SATURDAY AND SUNDAY: Strong upper level ridging builds across the
central CONUS Saturday, resulting in even warmer temperatures for
much of our area. Broad warm air advection and 850 mb temperatures
in the 97th-99th percentile yield high confidence in afternoon highs
reaching the lower 80s along and east of I-29, with values
approaching the mid to upper 80s in areas west. Despite summer heat,
dew points will only be in the 40s with gusty southwest gradient
winds. Gusts should peak in the 20s but could see occasional gusts
in the 30s if mixing is slightly deeper than expected, especially
downslope of the MN Buffalo Ridge. As alluded to in the previous
discussion, this will result in elevated fire danger across portions
of our area - more on this in the Fire Weather Section below.

Moisture starved front dives southward across the region Saturday
night, resulting in "cooler" highs Sunday. Currently have
temperatures ranging from the mid 70s to lower 80s - which is still
well above normal for this time of year. Winds will also be notably
lighter amidst upper ridging and a weak surface high.

MONDAY AND TUESDAY: Upper level ridging begins to push eastward
Monday as a strong upper level low over the Rockies ejects
northeastward across the central Plains. Despite the increase in low
level moisture associated with this wave, will still see dry, warm,
and breezy conditions prevail prompting widespread elevated fire
danger across our area.

Rain chances gradually return the forecast Monday afternoon, with
chances increasing more so during the evening with the aid WAA.
While the severe threat currently remains to our south, can`t rule
out the possibility of seeing a few strong thunderstorms, with
perhaps some elevated hailers. For now, will continue to monitor
trends and latest SPC guidance. Widespread rain chances (>80%) are
then expected Monday night through Tuesday as the aforementioned
upper level low lifts northeastward over Nebraska. Do think it`s
worth noting, however, that a high amount of uncertainty still exist
concerning rainfall totals due to the potential for dry-slotting and
convective showers. Nonetheless, still believe periods of moderate
to heavy rainfall will be possible, especially if thunderstorms
occur.

WEDNESDAY AND BEYOND: Model consistency begins to wane during the
latter half of the work week, with most guidance showing quasi-zonal
flow returning. Otherwise, expect more seasonal temperatures to
prevail during this time, with highs generally in the 40s to 50s and
overnight lows in the 20s to 30s.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1231 PM CDT Fri Apr 12 2024

VFR conditions are forecast to prevail this TAF cycle. Expect light
northwesterly winds to gradually turn southerly through the
afternoon, then southeasterly overnight. Sustained speeds and gusts
will increase during this time, with a brief period of LLWS possible
at KHON prior to daybreak. Otherwise, look for mostly sunny skies
and quiet conditions to continue Saturday.

&&

.FIRE WEATHER...
Issued at 323 PM CDT Fri Apr 12 2024

High to very high fire danger is expected to prevail across the
region Saturday as breezy south/southwesterly winds cause relative
humidity values to fall into the 20s. Gusts should peak in the 20s
but could see occasional gusts in the 30s if mixing is slightly
deeper than expected, especially downslope of the MN Buffalo Ridge.
Thus, with dry fuels still in place, have decided to issue a Fire
Weather Watch for portions southeast South Dakota, northwest Iowa,
and southwest Minnesota after collaboration with neighbors. We
strongly encourage you to exercise caution with any activity that
may cause a spark, as fires can spread quickly under these
conditions!

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Fire Weather Watch from Saturday afternoon through Saturday
     evening for SDZ040-055-056-062-067.
MN...Fire Weather Watch from Saturday afternoon through Saturday
     evening for MNZ071-072-080-081-089-090-097-098.
IA...Fire Weather Watch from Saturday afternoon through Saturday
     evening for IAZ001>003-012>014-022.
NE...None.

&&

$$

DISCUSSION...SST
AVIATION...SST
FIRE WEATHER...SST