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fxus63 kdmx 221053 

Area forecast discussion
National Weather Service Des Moines Iowa
553 am CDT Tue Oct 22 2019

Discussion.../today through Monday/
issued at 337 am CDT Tue Oct 22 2019

Main concern today continues to center around winds today and then
some precip chances north late tonight into early Wednesday.
Continue to see very strong winds and wind gusts across the area
early this morning with a deep 988mb surface low centered across southeast
Minnesota/wc WI. The surface low will quickly lift east northeast into
southern Ontario along with the upper level trough through the day.
Still have some very light rain/drizzle wrapping around the backside
of the low into the northern/northeastern areas of the forecast area
and this will continue through the mid morning hours before moving
off the north and east. Clouds will clear as the low moves off to
the northeast as well through the morning/early afternoon. Very
tight sfc pressure gradient in place currently along with a stronger
isallobaric component keeping winds sustained at or near advisory
criteria for much of the area. Have had one gust at Estherville last
evening to 50kts with the High Wind Warning in place. Winds aloft on
the VAD wind profile just off the deck at 2 kft are around 50-55kts
with hi-res models soundings indicating a deep enough mixed layer to
tap into these higher winds. However these stronger gusts are not
materializing, so mixing heights must be just lower with peak gusts
at most sites over the past few hours around 45 to 50 mph. Will keep
wind headlines as they are for now though as models suggest may get
some deeper mixing and could still tap into those stronger winds
just after sunrise and as clouds clear. Therefore a few sites may
still see high wind criteria toward sunrise. As the low pulls off
through the day, the pressure gradient will relax and winds aloft
will diminish some, but still potential for advisory criteria for
much of the day with winds expected to diminish toward evening.

The next upper wave will dig into the northern rockies and northern
plains late tonight into early Wednesday. This may spread some light
precipitation across the northern third of Iowa late tonight into
Wednesday morning with increasing cloud cover for central and
southern Iowa. May initially see a rain/snow mix across the north,
but expect precipitation to change to all rain as low level surface
temperatures warm. Any precipitation should be quite light. Much
cooler air builds in behind the system to end the week with 850 mb
temperatures around -4c. Thermal ridge then builds into the central
US ahead of a digging trough into the northern rockies with 850 mb
temps climbing to around 10c by Saturday with temperatures
moderating toward the seasonal averages. Another strong cold front
will drop through the state late in the weekend into early next week
bringing a return to below average temperatures as h85 temps drop to
around -8c by late Sunday into Monday. The colder temperatures will
remain in place through much of next week.


Aviation.../for the 12z tafs through 12z Wednesday morning/
issued at 553 am CDT Tue Oct 22 2019

Low clouds still around this morning, mainly MVFR and expect to
gradually rise to low VFR before diminishing by late morning.
Gusty westerly to northwesterly winds expected to diminish some
toward early evening and lose the gustiness tonight and become
more southwesterly. Some very light rain or drizzle possible at
kmcw or Kalo early this morning.


Dmx watches/warnings/advisories...
Wind Advisory until 4 PM CDT this afternoon for iaz007-027-028-

High Wind Warning until 10 am CDT this morning for iaz004>006-

Wind Advisory from 10 am this morning to 4 PM CDT this afternoon
for iaz004>006-015>017-023>026-033>037.


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