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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
309 PM CDT Friday Apr 18 2014

issued at 305 PM CDT Friday Apr 18 2014

High pressure ridge extended from the western Great Lakes to East Texas.
Skies have been sunny with light winds across the dvn County Warning Area. At 3 PM
temperatures ranged from the upper 50s to lower 60s. Elsewhere...lots
of temperatures in the 70s on the surface map from southern South Dakota to
the Southern Plains.


Short term...(this evening through saturday)
issued at 305 PM CDT Friday Apr 18 2014

Forecast focus on quiet and delightful Spring weather.

Tonight...patchy to areas of thin cirrus as the high pressure
ridge shifts slowly to the east. The dry airmass will allow for
minimum temperatures to drop into the middle 30s to lower 40s. However...
this is warmer than last night due to east to southeast winds staying
up at around 10 miles per hour.

Saturday...delightful Spring day to get a lot of yard work accomplished
with south winds blowing warm air into the dvn County Warning Area. Maximum
temperatures will range from the upper 60s to middle 70s. Other than
some thin cirrus floating across the sky there will be plenty of
sunshine. Gulf moisture will be cut-off due to a storm system in
the southeast United States and ridging in the western Gulf. There
will be a tightening pressure gradient as low pressure tracks from
the northern rockies into southern Canada...and high pressure is
situated over the eastern Great Lakes. South winds should gust to
25 to 30 miles per hour during the afternoon mainly west of the MS river. In
our far northwest County Warning Area some gusts may approach 35 miles per hour. Forecast soundings
indicate good mixing up to 825 mb.

There will be an enhanced grass fire threat Saturday afternoon for
portions of the County Warning Area due to the combination of strong winds and
relative humidity dropping into the middle to upper 30s range. This
will be especially true where some dry vegetation still exists but
meanwhile green-up will continue to progress with the warm temperatures.

Long term...(saturday night through friday)
issued at 305 PM CDT Friday Apr 18 2014

Active Spring weather continues through the extended. Models in
decent agreement through middle week...with a model consensus favored
in this time period. Model solutions diverge by the end of the week
and thus confidence in timing and other details is considerably
lower from Wednesday on.

Easter Sunday looks like another great day with warm southerly low
level winds and highs in the 70s. Clouds will be increasing during
the day ahead of the Sunday night system...but precipitation should hold
off until Sunday night when the upper forcing approaches.

Sunday night through Monday...
the upper over Southern California...moves into the Southern
Plains and continues to fill and weaken. Fragments of energy lifting
across the middle Mississippi Valley will result in a chance of showers
and storms Sunday night. The best precipitation chance will be Monday when
the upper trough and surface cold front pass through....providing
both the greatest focus and upper support.

Cold air behind the front will drop temperatures a bit...but not too
extreme with highs Tuesday and Wednesday in the 60s and lows in the

Middle-week system...a stronger upper low is prognosticated by long range
models to move into the northern plains late by Wednesday. Warm
advection and an open Gulf ahead of this system will support
increasing thunderstorm chances in the warm sector Wednesday through
Wednesday night. This is where differences in model details become
more obvious. 12z European model (ecmwf) continues to deepen the upper low through
Friday...and is faster with the main surface trough. On the other
hand...the 12z GFS begins to fill the upper low late Thursday and is
slower with the cold front. Either way...thunderstorm chances will
continue through the cold frontal passage Thursday or Thursday

Will keep lingering chance of showers next Friday for wrap-around
and strong cyclonic flow aloft.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 305 PM CDT Friday Apr 18 2014

VFR conds through this taf cycle. High pressure ridge over the
area for the remainder of this afternoon...gradually shifting to
the east. Winds becoming east this afternoon at less than 10 knots
then southeast tonight. South winds on Saturday increasing to
sustained 15 knots with gusts to 20 to 25 knots by afternoon.


Dvn watches/warnings/advisories...


short term...haase
long term...dmd