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000
FXUS63 KDMX 131136
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
636 AM CDT Sat Apr 13 2024

 ...Updated for the 12z Aviation Discussion...

.KEY MESSAGES...

- Well above normal temperatures this weekend with highs in the
  upper 70s to low 80s.

- Red Flag Warning in northern Iowa today as very high to
  extreme fire weather conditions are expected from a
  combination of the warm temperatures and gusty winds out of
  the south. Fire weather conditions elevated in central to
  southern Iowa. Burning is not recommended today.

- Thunderstorm chances return Monday late afternoon through
  Tuesday. Some strong to severe storms possible, but details to
  continue to be refined.

- Much cooler air arrives with the departure of the system
  midweek.

&&

.DISCUSSION...
Issued at 340 AM CDT Sat Apr 13 2024

Today:

Early morning conditions feature clear skies and light winds
which have helped temperatures fall towards freezing for some north
and west with otherwise temperatures in the 30s to 40s across the
area. With warm air advection already increasing, temperatures will
be quick to climb today after the chilly start as the thermal ridge
nudges into the state by the afternoon. As a result, high
temperatures today look to climb into the upper 70s to low 80s which
is about 20 degrees above normal, but forecasted values are not
quite reaching record values for April 13. In addition to the
surging temperatures, winds out of the south will also increase into
the afternoon as the pressure gradient tightens once again. The
warm, breezy conditions will combine with the otherwise dry
conditions to create another day with very high to extreme fire
danger and a Red Flag Warning has been hoisted in northern Iowa as a
result. See the fire weather section below for more information.

Tonight through Sunday:

Upper ridging remains through Sunday but a quick-moving shortwave
will slide a "cold" front through the area tonight into Sunday
morning. With profiles notably dry and little moisture to work with,
the main weather change will be the shift to winds out of the north
to northeast for Sunday with winds also remaining lighter.
Temperatures Sunday will likely be near to slightly cooler than
today, especially north.

Monday and Beyond:

Monday will be another warm day as winds turn out of the south again
with increasing warm air and moisture advection ahead of the
approaching system which will still be in the southwest U.S. moving
into the Southern Plains by 00Z Tuesday (Monday night). At the
surface, a warm front will be lifting into the area Monday afternoon
into Tuesday which will provide a focus for convection. At this
point, storms don`t look to develop until Monday night, aided by the
low level jet, but would be offset from peak heating and thus
keeping storms more elevated with primary hazards of large hail
and locally heavy rainfall. The warm, moist air remains into
Tuesday with the overall system expected to track across the
state Tuesday afternoon into Tuesday night. Much uncertainty
remains with regards to the severe potential on Tuesday with
lingering questions of where the warm front will end up and how
much clearing (if any) occurs on Tuesday morning provided
thunderstorm activity is expected to continue through the night
Monday into Tuesday morning, and may linger through the day
Tuesday. Widespread rain/storms continuing through the day would
limit the instability for severe convection to occur.
Conditions may still change with confidence likely to increase
as more hi-res data becomes available. At this point, continue
to monitor the forecast for updates and see the SPC Day 3/4 for
some additional details. Outside of the severe threat, rain
amounts look to be pretty good with mean ensemble 48-hour QPF
values of 1-2" by early Wednesday with locally higher amounts
certainly plausible.

Beyond Tuesday, an active forecast pattern continues through much of
the rest of the work week with some additional rain/storm chances in
addition to some cooler temperatures returning to the forecast
behind the departing system. May not want to use your warm
weekend this weekend to plant your garden annuals, though, as
low temperatures drop near to below freezing in the cool down to
end the work week which may bring some frost/freeze concerns
for any susceptible plants.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 630 AM CDT Sat Apr 13 2024

VFR conditions expected to continue through the TAF period with
just some passing higher clouds this afternoon into evening,
mainly central to south, before clearing again overnight. Winds
out of the south will continue to increase through the morning
to afternoon hours before diminishing again tonight. Gusts of
20-30 knots are expected, the highest gusts north. Low level
wind shear may develop overnight but have kept out of this
issuance as time window appears limited near KDSM, with better
potential near KOTM.

&&

.FIRE WEATHER...
Issued at 340 AM CDT Sat Apr 13 2024

Increasing winds out of the south and well above normal
temperatures will combine with the dry conditions and fuels to
create very high to extreme fire weather conditions across
especially northern Iowa today where a Red Flag Warning was
issued from midday to early evening. Minimum relative humidity
values fall towards 25-30% through much of the area but the
highest sustained winds and gusts will be in the north where
sustained winds of 20-25 mph with gusts up to 30-35 mph are
expected. Fuels in northern Iowa also remain mostly cured with
more green-up further south. Fire weather conditions will
certainly be elevated for those not in the Red Flag Warning so
outdoor burning is not recommended today as any fires that start
could spread quickly in these conditions. Warm conditions
remain on Sunday with similar minimum relative humidity values
but winds are expected to be lighter and out of the north to
northeast.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon today to 7 PM CDT this evening for
IAZ004>007-015>017-023>026.

&&

$$

DISCUSSION...KCM
AVIATION...KCM
FIRE WEATHER...KCM