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Area forecast discussion 
National Weather Service Des Moines Iowa
1126 PM CST Thursday Feb 26 2015

Short term /tonight/...
issued at 314 PM CST Thursday Feb 26 2015

Large area of Arctic high pressure to build into the state tonight
becoming centered over SW to central Iowa by 12z Friday. 850 mb temperatures
aloft very cold around -17c...with winds expected to diminish and
become light overnight. With the fresh snowpack...clear skies...and
light winds will allow temperatures to drop off overnight with very cold
temperatures expected overnight. Near record lows are expected across much
of northern Iowa. Wind chills will also be very cold in the 20 below
to 30 below range late tonight into Friday morning. However given
the winds which expected to be very light...will not issue a wind
chill headline at this time.

Long term /Friday through Thursday/...
issued at 314 PM CST Thursday Feb 26 2015

High pressure moves off to the east on Friday night with return
flow coming in overnight. The next weather system doesn't have a
lot of reflection at the surface...though there is a decent shortwave
moving through. The track has been shifting south with successive
model runs and it is likely the snow axis will be south of the
County Warning Area. Feel there is a good chance for snow across the whole County Warning Area Sat
night and sun...but amounts will not be all that great with the
best support to the south and the 500 mb confluence zone remaining
south as well.

Another shot of cold air follows...but only briefly. The western
U.S. Trough hangs back after the first impulse comes out Sunday
with another more significant shortwave for Monday night and Tuesday. More
warm air will be drawn north ahead of this feature as it is
southwest flow feature and not out of the northwest as has been
the case recently. Precipitation will begin as snow...but with the warmer
air streaming in will become mixed over at least the southeast
half of the state...and will likely turn to all rain over the
southeast on Tuesday. The warmer air was hinted at...though not
unanimous...yesterday. Today the message is clearer with maximum
layer temperatures in the +10 c range. Went with mixed precipitation on
Tuesday...back to snow before ending on the back side of the low
Tuesday night.

Another shot of well below normal weather will move into the upper
Midwest for Wednesday and Thursday...though not as cold as the
past few airmasses Ave been.

&&

Aviation...27/06z
issued at 1126 PM CST Thursday Feb 26 2015

Widespread VFR conditions are expected for much of the forecast
period. Only issue would be on Friday afternoon with low level
clouds and a few flurries with soundings showing some saturation just
above 1kft. Otherwise...skies will be clear with unrestricted
visibilities and ceilings. Light northwest winds will become light
southwest winds on Friday and eventually southeast by late Friday
evening.

&&

Dmx watches/warnings/advisories...
Wind Chill Advisory until 9 am CST Friday for Black Hawk-Boone-
Bremer-Butler-Calhoun-Carroll-Cerro Gordo-Emmet-Franklin-Greene-
Grundy-Hamilton-Hancock-Hardin-Humboldt-Jasper-Kossuth-Marshall-
Palo Alto-Pocahontas-Poweshiek-SAC-story-Tama-Webster-Winnebago-
Worth-Wright.

&&

$$

Short term...beerends
long term...MS Feb 15
aviation...cogil

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