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Area forecast discussion 
National Weather Service Des Moines Iowa
708 PM CDT Friday Oct 9 2015

Short term /tonight/...
issued at 418 PM CDT Friday Oct 9 2015

High pressure will push south across Missouri River valley...keeping
conditions dry overnight. High will bring increasing dry air... and
expect skies to continue to clear. However...will also see return to
warm air advection...especially in the west with winds becoming southerly. Have
therefore kept temperatures warmer than previous night and
slightly above going. With lighter winds...may be too warm.

Long term /Saturday through Friday/...
issued at 418 PM CDT Friday Oct 9 2015

Little change to previous forecasts with a warming trend through
the weekend then mild and dry through next week. The high pressure
shifts to the southeast tonight with warm advection commencing.
Warmer on Saturday with highs in the low to middle 70s. The thermal
ridge will settle over Iowa on Sunday in advance of a cold front
that will arrive Sunday night. Still on track for near record to
record highs on Sunday with readings in the low to middle 80s. Have a
high forecast of 87 at Des Moines with the current record sitting
at 86. The amount of mixing and ability to mix drier dewpoints
down to the surface could push temperatures warmer than current
forecast. The boundary passes through Sunday night and early
Monday. The boundary will pass through dry with very little
moisture to work with and warm air aloft limiting vertical ascent.
With good mixing...winds will approach Wind Advisory criteria on
Monday with cold advection aiding Transfer momentum efficiency of
mixed layer winds to the surface. Some gusts near 40 miles per hour will be
possible. Another boundary will pass through the area late in the
period again with limited moisture. No significant pushes of cold
air with any unseasonably cold air mass well to the north and


issued at 704 PM CDT Friday Oct 9 2015

Ceilings will remain at high levels as cirrus streams over the
state tonight into early Saturday. Otherwise...widespread VFR
conditions will persist with relatively light winds overnight
becoming south and increasing on Saturday.


Fire weather...
issued at 418 PM CDT Friday Oct 9 2015

Primary fire weather concerns will revolve around fall harvest and
the recent dry stretch. Monday in particular will represent a high
fire growth day and will present a danger for quickly spreading
field fires generated by agricultural equipment during harvest.
Wind gusts from the northwest to near 40 miles per hour lead to quick fire
expansion. Afternoon humidity values Monday afternoon will in the
upper 20s to lower 30s therefore will be near red flag criteria.


Dmx watches/warnings/advisories...none.



Short term...awb
long term...donavon
fire weather...donavon

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