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National Weather Service Des Moines Iowa
640 am CDT Tuesday Sep 2 2014

issued at 317 am CDT Tuesday Sep 2 2014

Fast moving shortwave will exit the County Warning Area this morning with high pressure
following today. The high will move to the east of the County Warning Area
tonight. A cold front will will move into the state Thursday and
pass to the southeast by Friday. Cool high pressure will follow.


Short term /today/...
issued at 317 am CDT Tuesday Sep 2 2014

Another shortwave is currently moving into northwest Iowa and will
push across the state this morning. Pretty decent vorticity maximum embedded
in the wave as well which had fired convection out over Nebraska and
South Dakota earlier in the evening. The storms held together and
as they entered western Iowa produced 40-50mph wind gusts. The gust
front outran the storms as they pushed into the western forecast
area so wind isn't looking as impressive. However...these storms are
very pulsy and with 50dbz heights being significantly lower tonight
than they were the past couple of nights they are being closely
watched for the potential for large hail. A couple storms have come

All models are in decent agreement on moving the shortwave east
during the middle to late morning with convection waning during this
time. The rest of today should be dry and quite sunny. Highs today
will be tricky. We have considerably lower dewpoints today and with
ample sun we should warm up pretty nicely but with a west to
northwest component to the wind we will likely see temperatures comparable
to yesterday.

Long term /tonight through Monday/...
issued at 317 am CDT Tuesday Sep 2 2014

Winds will swing to the south as the high moves to the east of the
County Warning Area tonight. Theta-E advection will begin...but it appears it will
be late night before isolated thunderstorms develop. Area of
isolated to scattered thunderstorms will push northeast during the
day Wednesday as very humid airmass returns to the state.

Thursday looks ot be the warmest day with dew points will into the
70s. Temperatures will be held down some by a combination of
factors...including wet antecedent conditions...late season sun
angle...and some lingering cloudiness. Went close to 90 south with
80s north. Air mass will become capped for a period of time Thursday
into early Thursday evening. Temperatures fall overnight and will allow
for a squall line to develop ahead of the cold front. Upped probability of precipitation
to the likely category fro Thursday night.

High pressure will push the moisture south on Friday with
significant cooling expected for Friday into early next week with
temperatures holding below normal for several days.


issued at 640 am CDT Tuesday Sep 2 2014

Locally dense fog will affect primarily kotm through 14z before
conditions become VFR. An upper level disturbance shifting across
northern Iowa has kept scattered thunderstorms and rain going all nightand is currently
affecting kmcw and Kalo. These are pulse storms that briefly
intensify and may drop hail to the size of nickels and/or wind gusts
to 30kts. The storms are expected to exit the kmcw and Kalo taf
locations over the next 2-3hrs. After which conditions will become
VFR. Late in the period a warm front will lift into the state and
bring a chance for thunderstorms and rain mainly to kdsm and kfod.


Dmx watches/warnings/advisories...


Synopsis...MS Sep 14
short term...fab
long term...MS Sep 14

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