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Area forecast discussion 
National Weather Service Des Moines Iowa
623 am CDT Sat Oct 10 2015

Short term /today/...
issued at 244 am CDT Sat Oct 10 2015

Interesting overnight...prior to the onset of warm air advection
across the area...temperatures in a small corridor from Clarion to
Forest City/Mason City and near Carroll dropped into the middle to
upper 30s between 06 and 11z. For a small portion of north central
Iowa added patchy frost to a few northern counties...though most
likely relegated to low lying areas only. For today...few concerns
anticipated. A quick look at subjective h850 analysis shows that
warm air is already moving into the area this morning and will be in
full swing by 00z this evening. 850 temperatures 00z Saturday topped out at
6c and should be nearly 10c warmer by 00z Sunday...about 14c east to
nearly 16c west. A surface warm front has already formed to our west
over the Dakotas and will move rapidly east today. Bufr soundings
show that mixing will increase across the region after 1 PM this
afternoon with sustained winds from the southwest at nearly 20 miles per hour
over the west and north with gusts to nearly 35 miles per hour at times through
late afternoon. With the stronger mixing to nearly h800...
temperatures should recover nicely during the afternoon hours today.
Across the east...where slightly cooler air will still reside highs
will reach the lower 70s and in the west temperatures should be
closing in on the upper 70s. About the only concern that might slow
the temperatures down today would be some high cloudiness.
However...looking at the irsat looks like the clouds
will have only a small influence on temperatures for the afternoon
hours. Otherwise...expect a rather pleasant fall October day across
the region.

Long term /tonight through Thursday/...
issued at 244 am CDT Sat Oct 10 2015

Fairly benign weather throughout the period with no precipitation to speak
of. Biggest issue will be temperature changes with frontal boundary
passages and winds. Westerly flow aloft in place tonight with
southwesterly low level flow and warm air advection in advance of a developing area
of low pressure centered over the prairie provinces of Canada. This
low is associated with an upper level wave moving through The
Rockies...and is expected to strengthen as it moves east-southeast into the
Great Lakes region by Monday. Much warmer air will build into the
state ahead of the low...with 850 mb temperatures increasing into the 20s
celsius and moisture increasing as well with dewpoints expected to
push into the upper 50s to around 60. The associated cold front to
sweep through Iowa Monday night...with strong northwesterly winds
expected for Monday. 850 mb temperatures drop to around 6c by
expect temperatures back down in the 60s to around 70. Gusty northwest
winds expected with a tightened surface pressure gradient in place and cold air advection.
All models pointing toward a windy conditions...with the GFS
strongest but looking somewhat overdone giving the strongest cold air advection
already through the County Warning Area. Therefore stuck closer to the NAM/sref at
this time still suggesting 30-35 kts at the top of the mixed layer
in BUFKIT. Therefore did bump up winds and wind gusts a bit could likely see advisory criteria winds across at least
the northern into the central County Warning Area Monday. Much drier air in place
will also allow relative humidity values to dip to around 30 percent by the
afternoon hours.

Northwest flow pattern then to remain across the County Warning Area through the end
of the forecast period...with mild and dry conditions. Another weak
shortwave trough to push southeastward into the Great Lakes to end
the week...could bring some additional cloud cover and drop temperatures a
bit back into the 60s by Friday.


issued at 622 am CDT Sat Oct 10 2015

Main concern today will be wind. Increasing southwest flow aloft
will mix to the surface after 16z most areas with gusts near 30 kts
north and to 18 to 25 kts central. Winds relax by 23z with
persistent south southwest flow until 12kt remainder of period.


Fire weather...
issued at 244 am CDT Sat Oct 10 2015

Fire weather concerns to revolve around fall harvest and the
recent dry stretch. Monday could still 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 40 miles per hour or higher could lead to quick
fire expansion. Afternoon humidity values Monday afternoon will be
in the upper 20s to lower 30s...resulting in conditions near red
flag criteria.


Dmx watches/warnings/advisories...


Short term...rev
long term...beerends
fire weather...beerends

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