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Area forecast discussion 
National Weather Service Des Moines Iowa
306 am CDT Mon Jul 25 2016

Short term.../today/
issued at 306 am CDT Mon Jul 25 2016

Quiet wx expected for the short term. Mainly clear skies expected
across the northern County Warning Area...with some mid clouds across the southern
half especially this morning. County Warning Area will be in a region of little if
any forcing. High pressure will dominate the wx. Have tweaked
temperatures slightly from going fcst. May see some patchy light fog
toward sunrise but should mainly be of the aviation type and will
burn off quickly.

Long term.../tonight through Sunday/
issued at 306 am CDT Mon Jul 25 2016

Main trends continue on track for most of the week. Tonight and Tuesday
will continue to be dominated by high pressure over the area with
few if any clouds other than some high based cirrus. Gradually the
high will move east of the region by Tuesday morning with light winds
throughout the region. Though wont include in forecast at this time...there
may be some patchy ground fog by Tuesday morning despite the lower
dew points across the region. Not expecting any real impacts to traffic
at this time. Other than that temperatures will remain warm with afternoon
highs still reaching the upper 80s over the south and in the mid 80s
across the north. Overall the trends with the midweek convection have
slowed...with an apparent start time of mid to late morning for most
of the region west of i35 and the better chances remaining over the
west half the balance of the afternoon hours. With cloud cover highs
will be cooler on Wednesday and guidance in The Ball park with lower
80s northeast and mid 80s across the south.

There continues to be divergence in model solutions with regard to
the evolution of the mid to late-week system. The Euro and Gem are
generating a closed surface low with the passage of the next mid level
wave...with the Euro model nearer Iowa while the Gem is tracking much
farther south of the state. The GFS has more of a diffuse system tracking
south of the state. The more organized Euro generates several inches
of rainfall by the end of the week over Iowa while the GFS keeps the
heavier rain south and west of the state. The difference in the models
is arising due to differences in the development of a Midwest trough
aloft and the progression /evolution of the upper level trough. The
GFS is progressive with no phasing taking place between the two waves
as they cross the Midwest. The Euro on the other hand suggest the first
wave slows and the second wave arrives/phases and deepens the entire
trough closer to Iowa. With better dynamics aloft a surface system would
then be more likely to develop. Though correctness in either solution
is questionable for now...the Euro is generally better at timing the
movement of systems between 3-5 days compared to the GFS. However
..climatology would not generally favor a deepening wave over the
Mississippi River valley this time of year. For now will continue
trends of increasing pop from Wednesday through Friday... with lingering
thunder chances even on Friday. The latter portion of the week looks
wetter and cooler in either case...with the Euro having a wetter forecast
at this time. Given the clouds and precipitation...highs will be held
back in the 70s to lower 80s and lows in the 60s. Late in the period
and closer to the weekend conditions should improve with departure
of the system though some may return toward Saturday night and Sunday...
giving the region only about 24-36 hours of dry weather.


Aviation.../for the 06z tafs through 06z Monday night/
issued at 1139 PM CDT sun Jul 24 2016

VFR conditions will prevail through the entire taf period.


Dmx watches/warnings/advisories...


Short term...zogg
long term...rev

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