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000
FXUS63 KDMX 091102
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
602 AM CDT Sun May 9 2021

.SHORT TERM.../Today through Monday/
Issued at 245 AM CDT Sun May 9 2021

Confidence: Medium to High

Beneficial rainfall continues over the region at this time.
Elongated sfc trough/low with ample upper level support, strong
frontogenesis and moisture transport into the boundary have combined
to bring much of the area rainfall. Despite the coverage, the
northernmost areas have seen much less with this event. Thunderstorms
continue over southern areas of Iowa now with a large MCS
propagating across Kansas and Missouri. The H850 low and surface
features will continue to move east across Missouri/Illinois
through 12z with lingering showers over the south/central areas
mainly through 12z. Gradually through 18z, some breaks and
clearing will take place from northern and eventually south into
central/south by 00z as weak high pressure briefing replaces the
exiting system. The Euro/GFS both project afternoon H850 temps
recovering to around 2 to 3C. This will allow afternoon highs to
reach the upper 50s to around 60 degrees central/north while the
southeast, where more clouds will linger into early afternoon,
will reach the mid 50s. A lingering trough of low pressure north
of the exiting system today will swing around the departing low
later tonight into Monday and extend back west into Iowa and areas
east. Though generally lacking moisture, the low along with a
backdoor cold front will have enough lift to produce a few showers
from either late morning to afternoon or perhaps mainly afternoon
across the east/central/southeast as weak instability develops
during that time. Have added some PoP over the these areas for the
afternoon hours for now. Little if any precipitation is anticipated
and the better chances of any rain or iso thunder will be nearer
Ottumwa by late afternoon. The next few nights will be chilly with
lows tonight reaching the mid to upper 30s with lower 40s in
urban areas. A few locations north may see some brief morning
frost. Highs Monday will peak in the upper 50s to lower 60s once
again with the clouds and associated showers.

.LONG TERM.../Monday Night through Saturday/
Issued at 245 AM CDT Sun May 9 2021

Confidence: High through Friday; Medium Saturday

Monday night into Tuesday morning high pressure follows the
departing weak low and cold front. This will result in a greater
chance for more widespread frost; especially from the river valleys
in eastern Iowa through much of northern Iowa along and north of
Highway 20. Fairly benign pattern remainder of the week with a
gradual warming the highlight of the week. Overall, high pressure
will dominate for Tuesday into Wednesday as temperatures warm to the
60s with overnight lows in the upper 30s to lower 40s. By Thursday,
an approaching system will increase some moisture return with
showers and thunderstorms reaching western boundary of the forecast
area. As warm air advection increases into Friday and the H850 flow
becomes more favorable for return moisture transport, showers and
some thunderstorms will build across the region through the day. The
operational models then drift apart with the GFS running the system
east southeast by 12z Friday and high pressure replacing the
departing low. The Euro is much slower and holds onto the
blocking Great Lakes high which keeps the showers and scattered
storm chances over our area through at least Saturday. At this
time, it would be more likely that the slower solution based on a
more stubborn Great Lakes high is the preferred one. Thus, next
weekend will likely have more clouds and shower chances around
with seasonally warm highs in the lower to mid 70s along with lows
a more reasonable upper 40s to mid 50s.

&&

.AVIATION.../For the 12Z TAFS through 12Z Monday morning/
Issued at 602 AM CDT Sun May 9 2021

System continues to pull east with MVFR cigs still lingering over
the area at KDSM/KOTM through 13-17z. Otherwise, most sites
already VFR with clearing northeast. Northeast winds remain at 10
to 15kts with higher gusts southeast sites as well. Aft 00z light
winds return. /rev

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...REV
LONG TERM...REV
AVIATION...REV