Altoona, Iowa 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

797
FXUS63 KDMX 301742
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
1242 PM CDT Sun Mar 30 2025

 ...Updated for the 18z Aviation Discussion...

.KEY MESSAGES...

-Few storms southeast this morning, and rain/snow mix north through
this afternoon with departing system

-Additional showers and storms Tuesday-Wednesday, with severe
weather possible late Tuesday into Wednesday

-Active weather remains with another possible system impacting
 Iowa Friday into the weekend

&&

.DISCUSSION...
Issued at 350 AM CDT Sun Mar 30 2025

A calmer morning across central Iowa following a more active evening
as some strong to severe storms pushed through portions of central
Iowa. Most notably with this activity was a handful of wind gusts in
Polk County around 55-60 mph, along with hail further east into
Jasper County around a half inch to quarter size late last night.
Radar early this morning shows these showers and storms largely
lingering over the northeast portion of the state, remaining below
severe limits and should move out of the state over the next few
hours. At this point, the cold front is through the majority of the
state, where temperatures are currently in the upper 30s to 40s with
north/northeast flow, while southeast Iowa remains in the warm
sector yet with south/southwesterly flow and temperatures in
the 50s to mid 60s. The low pressure system currently centered
over southern Iowa will continue to track northeastward into the
Upper Midwest today, which will gradually bring cooler
temperatures for all areas of the state later today. Northwest
flow overhead will allow for breezy winds with gusts up to 20-25
mph, with highs reaching into the upper 30s west and in the low
to mid 50s east. Before this happens, lingering convection
currently exiting Kansas into northern Missouri will gradually
lift into southeastern Iowa just before or around sunrise and
remain through the morning hours, which given lingering moisture
and instability within the remaining warm sector could bring
another chance for showers and storms with some hail and gusty
winds, though the overall severe risk is low. Meanwhile, lift
mainly along and north of I-80 with the departing low pressure
to the northeast per guidance will result in the formation of
wrap- around precipitation through the morning hours and into
the afternoon. At least through the morning, this precipitation
looks to remain as rain, though the afternoon hours per
soundings indicate cooling of the saturated column to values
below freezing over northern into north-central Iowa, which will
allow for a transition to a wintery mix at times to snow.
However, as the system tracks out of the state around and after
sunset, any snow should end, so an overall small window to see
this snow. Given warmer ground temperatures and overall wet
surfaces, any falling snow should be limited in sticking only to
grassy areas at most, with overall minimal impacts expected.
High pressure sinks southeast into Iowa late Sunday through
Monday, with northwesterly flow keeping cool and dry air
overhead. Dry and quiet weather is expected with highs in the
40s to low 50s under partly sunny skies.

Monday evening into Tuesday, low level southerly flow brings a
return of warmer air into western Iowa, gradually filling in across
the state through the day. This will allow for temperatures to reach
into the 50s to low 60s in the southwest, while further north and
east remains cooler with temperatures in the low to mid 40s. Given a
better signal for gusty winds to mix down to the surface with this
push of warm air advection Tuesday, an increase in winds has been
collaborated with neighbors to push slightly higher gusts, with
values up to 30-40 mph expected. A shortwave over the Dakotas looks
to track into northern Iowa and southern Minnesota Tuesday morning,
bringing a chance for a rain/snow mix over the area. This is ahead
of lee-side cyclogenesis occurring Tuesday evening, with a
well- defined low pressure system lifting northeast into Iowa by
Tuesday evening into Wednesday. With the warm sector over Iowa
during this time, widespread rainfall is expected through the
day while snow looks to develop within a more defined area of
lift into Minnesota. Model soundings also indicated instability
values around 1000 MUCAPE with impressive effective shear values
around 80 knots and steeper mid-level lapse rates Tuesday night
into early Wednesday. Fast- moving storms Tuesday evening into
Wednesday are possible, with wind and hail the main threats. The
SPC highlights a 15% severe weather risk into central Iowa
which highlights the potential coverage area well. Details will
be refined over the coming days with close monitoring. On the
synoptic scale, winds look to remain breezy through Wednesday as
well, with southwest flow bringing gusts around 30-35+ mph.

High pressure settles overhead Thursday, with dry weather before
another period of active weather looks to impact the state sometime
Friday into the weekend. Models diverge in solutions regarding
coverage of a larger system developing in the Southern Plains, so
confidence remains low on potential impacts and will be watched
closely over the next several days. Temperatures during this time
frame look to generally be on the seasonal side, with highs in the
50s to low 60s and low temperatures in the upper 20s to 30s.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1242 PM CDT Sun Mar 30 2025

Low ceilings and restrictions to visibilities are expected
across the northern half of Iowa this afternoon into the early
evening as areas of drizzle and light snow are likely to
persist. The precipitation comes to an end by mid to late
evening with improving conditions toward daybreak on Monday. VFR
conditions will become widespread by the end of the forecast
period as ceilings improve. Surface winds remain strong from the
northwest this afternoon and this evening but slowly weaken
into Monday morning.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...None.

&&

$$

DISCUSSION...Bury
AVIATION...Cogil