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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
617 PM CDT Friday Mar 27 2015

Synopsis...
issued at 245 PM CDT Friday Mar 27 2015

12z upper air analysis has the main 850mb cold front from New England to
the Gulf Coast with a secondary front from the eastern Great Lakes
into central Missouri. An upper level disturbance was in
Saskatchewan Provence moving into the Dakotas. Satellite trends
through middle afternoon show middle/high level clouds moving southeast
through the plains with low clouds across the Ohio Valley.

18z surface analysis has high pressure from Lake Superior into the
Southern Plains. A warm front ran from the western Dakotas into
western Kansas. Dew points were in the single digits and teens
across the Great Lakes and upper Midwest with 20s and higher from
the plains into the Ohio Valley.

&&

Short term...(this evening through saturday)
issued at 245 PM CDT Friday Mar 27 2015

Quiet and dry conditions will continue from late afternoon through
midnight as the high slowly moves east. After midnight a clipper
type system will pass to the south and west of the area. At the very
worst some flurries may catch the southwest part of Scotland County
right around sunrise.

Light easterly winds tonight and initially clear skies will allow
temperatures to drop significantly for overnight lows. Favored cold
areas should see lows in the teens.

Quiet and dry conditions will be seen on Saturday as yet another
high pressure slowly moves through the Midwest. Temperatures will
continue to average 10 to 15 degrees below normal.

Long term...(saturday night through friday)
issued at 245 PM CDT Friday Mar 27 2015

Warming trend starting Sunday with increased chances of rain into late
next week.

Long term forecast confidence assessment...fair to poor with main
issue is temperatures on Sunday with light rain and strong warming.
Second is light to moderate rain events middle to late week in active
zonal upper flow pattern with timing and locations a concern due
to run to run variances. Temperatures also could be off by 5 plus
degrees with strong warm air advection and if skies become fair next week.

Overview...initialization and verification shows bl once again is too
moist by American solutions suggesting too high quantitative precipitation forecast amounts Sunday
and also bl temperatures a category or more too cold making with 15
to 25+ miles per hour south winds risk of freezing rain none or almost none.
Preferred weighting is 70/30 mix of hi-res European model (ecmwf) with GFS into day
4 and then hi-res European model (ecmwf) day 5 beyond.

Saturday night...increased clouds and south winds increasing after midnight.
Area lows should be between 9 PM and 1 am with increasing temperatures toward
daybreak...especially west 1/3 as south winds increase to 10 to 20+
miles per hour by 4 to 5 am. Have low probability of precipitation far west after 4 am which based on forcing
may be able to delayed until after 7 am by later shifts.

Sunday...cloudy...light rain likely and blustery to windy with south
to southwest winds of 15 to 30 miles per hour. Rain totals should be mostly in
the .05 to locally near .2 inches. Good maximum temperature gradient suggested
with lower 40s possible far NE to around 60 degrees far west and SW
sections as skies clear there.

Sunday night through Wednesday...dry to mostly dry and mostly above
normal temperatures. Highs Tuesday/Wednesday may be still too low with sunshine
and good mixing on SW winds for later shifts. Mins Monday and Tuesday
night well above freezing for a change with upper 30s to middle 40s. Rain
chances late Wednesday PM and more likely Wednesday night.

Thursday and Friday...unsettled and mostly near normal temperatures
with favored pattern for light to moderate rain totals with moderate
strength fast moving system. Any storm risk is unlikely as surface low
and instability should stay or track to our south.

&&

Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 612 PM CDT Friday Mar 27 2015

VFR conditions will persist through Saturday evening with mainly
scattered-broken high level cloudiness as a quick moving upper level
disturbance passes to the west. At the surface... a ridge of high
pressure will shift across the area tonight and move into the
Ohio Valley on Saturday with light winds becoming southeast 5-10
kts.

&&

Dvn watches/warnings/advisories...
Iowa...none.
Illinois...none.
MO...none.
&&

$$

Synopsis...08
short term...08
long term...Nichols
aviation...05

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