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fxus63 kdmx 172342 

Area forecast discussion
National Weather Service Des Moines Iowa
642 PM CDT Thu Oct 17 2019

Discussion.../tonight through Thursday/
issued at 348 PM CDT Thu Oct 17 2019

The primary weather themes into next week will be warm and windy
conditions tomorrow with somewhat elevated fire weather concerns,
a brief window of weak convection early Saturday, and then another
episode of wind and rain early next week. No temperature extremes
in either direction are anticipated on either side of the system
next week.

Upper level ridge will pass through the Midwest tonight leading
to warmth and windy conditions Friday. Temps have been pushed to
the top of guidance or beyond so have leaned in that direction
again tomorrow with 70+ expected south and west. The dry airmass
promoting this warming will also mix well with peak gusts likely
40+kts west and north by afternoon with wind advisories quite
possible. Nmmb soundings are less bullish with more low level
moisture, but this is often a bias. The warmth, wind and
seasonally drying fuels will elevate fire weather conditions, but
not to the extent of red flag conditions due to dewpoints
remaining in the 40s and relative humidity values similar.

By the start of the weekend our attention will turn to the
current trough approaching The Rockies. This should reach the
plains Friday evening with deep forcing drying hard to generate
precip Friday night, but limited 1-3km moisture may hold off much
from occurring until the early morning hours Saturday when deeper
saturation should occur. This will lead to showers central and
east Saturday morning before exiting fairly quickly by midday and
clearing west by afternoon. It will be mild again with minimal
airmass change behind the trough/weak front.

The fast Pacific flow following this system will eventually
buckle leading to a plains low and rapid cyclogenesis Sunday
driven by the jet and associated noted pv anomalies. This will
result in deep phased deep forcing and low level convergence with
the front and a round of convection. Instability is not great,
the soundings saturate fairly quickly, but both deep and shallow
shear is quite strong leading to at least a minimal severe weather
threat late in peak heating, especially in the instability can
become more bullish. Any appreciable precip should end overnight
with increasing wind and somewhat cooler temperatures. Both
sustained speeds and gusts may again be met for wind advisories
north Monday.

The remainder of the forecast is essentially dry outside of a
recent model consensus of small chances north Thursday. Confidence
is quite low in this regard however with models depicting
different solutions on timing of the next short wave dropping into
the persistent Continental U.S. Mean trough.


Aviation.../for the 00z tafs through 00z Friday evening/
issued at 642 PM CDT Thu Oct 17 2019

High confidence in VFR conditions through the period with only
some scattered to broken high clouds expected. Strong winds just
above the surface late tonight/early Friday may cause some low level wind shear
issues, especially at kfod/kmcw. These strong winds will mix down
during the day Friday, with gusts of 30-40kt possible across the


Dmx watches/warnings/advisories...none.


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