950
FXUS63 KDMX 010020
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
620 PM CST Sun Nov 30 2025

 ...Updated for the 00z Aviation Discussion...

.KEY MESSAGES...

- More chances for accumulating snow return to at least the
  southern half of the state on Monday. Snowfall amounts of 2 to
  4 inches are possible in southern Iowa, with amounts generally
  around an inch or less farther north.

- Cold temperatures continue through the week. Coldest
  temperatures will be overnight Wednesday into Thursday morning
  with wind chills in the teens below zero possible.

&&

.DISCUSSION...
Issued at 248 PM CST Sun Nov 30 2025

With our weekend system departing to the east and high pressure
filling in behind, winds are diminishing over the state. With this
high pressure has come cooler air and temperatures have only reached
the upper teens to low twenties early this afternoon. Currently,
skies are mostly clear over northern Iowa and remain clouded in over
southern Iowa. This stratus deck is sitting right on the edge of the
dendritic growth zone, which has allowed for transient flurries
today. The evolution of the cloud deck through the night will impact
overnight lows, as clearer skies will allow temperatures to cool
more than cloudy skies. Stratus may fill in some, but will generally
be thin and patchy through the night, which will allow some
locations to cool considerably, especially in the north and east.
Should temperatures really drop out, some of the guidance is trying
to produce fog in northwest Iowa. However, radiation fog isn`t
typically the type of fog you expect to see with a fresh snowpack,
especially with dewpoints in the single digits.

As we get into early Monday morning, we`ll be looking at another
shot of snowfall beginning in southwest Iowa by around 6 am and
continuing over at least the southern half of the state for much of
the day. This event won`t be near the behemoth that moved through
yesterday, lacking many of the forcing mechanisms that were in place
over the weekend. The best band of frontogenetical forcing remains
well to our south in Missouri, as does any low-level/WAA component
of lift. Therefore, most of the snow will develop as a result of
broad scale lift generated by the trough, as indicated by the
stronger QG convergence in the 700mb to 500mb layer, most of which
actually falls mostly at the top of and above the dendritic
growth zone. However, the DGZ will be fairly deep with cold
vertical . profiles, suggesting snow-to-liquid ratios will be a
bit higher than what we saw on Saturday. Cobb guidance is
indicating SLRs in the 15:1 to 20:1 range, producing a fluffy
and efficient snow. Will be interesting to see how these ratios
are affected by lift above the DGZ rather than within it. The
snow will also be falling intermittently through much of the
day, which will allow for more residence time under the light to
moderate snowfall. All this to say, we could very well pick up
another 2 to 4 inches of snow over the southern half of the
state on Monday, with some locations over 4 inches possible in
southern Iowa. With this snowfall riding the coattails of
yesterday`s winter storm and this being the return to
school/work for many after the thanksgiving holiday, have
decided to issue a Winter Weather Advisory beginning Monday
morning for portions of southern Iowa. Fortunately, winds will
be fairly light as the snow moves through. Areas farther north
into central and north central Iowa may also see snowfall, but
will be less around an inch or less.

Snow wraps up on Monday evening with only token precipitation
chances here and there through the remainder of the week. Cold
temperatures then become the main story through the work week,
especially on Wednesday into Thursday as a cold front brings colder
temperatures down into the state. Overnight lows on Thursday night
are forecast to fall below zero, with wind chills nearing the
negative teens to near negative twenty on Thursday morning. Highs
don`t improve much on Thursday and wind chills stay in the single
digits below zero. Temperatures then "warm" slightly into
Friday as we get return flow on the backside of the high, but
still remain cool through the weekend.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 620 PM CST Sun Nov 30 2025

MVFR stratus covers much of Iowa this evening, though a few
areas have cleared. Have maintained MVFR stratus across all
sites through tonight, though brief breaks are possible
overnight. Stratus that persists overnight is expected to lower
to IFR, filling in towards 12z. A system will bring snow to the
southern half of Iowa on Monday, impacting KDSM/KOTM and
perhaps reaching to KALO where a prob30 group has been included.
Visibility is expected to fall to under 2 miles in snow. Snow
move out of the area at the end of the TAF period.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 9 AM to 9 PM CST Monday for
IAZ074-075-084>086-095>097.
Winter Weather Advisory from 5 AM to 6 PM CST Monday for
IAZ083-092>094.

&&

$$

DISCUSSION...Dodson
AVIATION...Hagenhoff