Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 271116

Area Forecast Discussion
National Weather Service Quad Cities IA IL
616 AM CDT Mon Mar 27 2017


Issued at 301 AM CDT Mon Mar 27 2017

Stratus.  While some upper air features have moved in the past 24
hours, the low clouds have not, and that is by far the main impact
on weather over the upper Midwest this morning. Light rain showers
are spreading northeast from Missouri and Kansas, and have reached
far southern Iowa as of 2 AM. Most of this activity is very light.


.SHORT TERM...(Today and Tonight)
ISSUED AT 301 AM CDT Mon Mar 27 2017

Rains continue to look on track for the southern 1/2 of the CWA or
so today. Near Interstate 80 is the cut off, and represents a sharp
gradient from a dry forecast to rather high pops due to the
stratiform nature of the light rain. The main bought of forcing
today will be timed through about late morning. A wetting light rain
is expected, especially along and south of Highway 34 in Iowa and
west central Illinois/northeast Missouri, and this will be handled
with a period of categorical pops.  Rainfall amounts should be on
the order of 0.01 to 0.15 in most spots, with near 0.20 in the far
south. The unrelenting cloud cover, light north winds, and light
rain will serve to hold temperatures down again, and I have gone
slightly under the guidance blend for highs today, in the lower to
mid 50s. Tonight, while dry weather will be expected, the low clouds
should rule the night again, and lows should only fall to the lower
to mid 40s in most areas, much like the current period.

.LONG TERM...(Tuesday through Sunday)
ISSUED AT 301 AM CDT Mon Mar 27 2017

Active flow regime remains for the long term period with a few
chances for precip through the period.  Main forecast concern will
be agreement between guidance on forecast solutions and subsequent
confidence in the long term forecast.

At the beginning of the long term, zonal to SW flow will bring in
the next warm air advection wing of precip.  Guidance remains
different in placement in the upper level waves.  This means that
precip for overnight Tuesday into Wednesday shows different QPF
placement and amounts.  The chance for measurable precip seems
likely, however total magnitude of this precip is still hard to
determine with the guidance differing from a quarter of an inch area
wide to near an inch in other model guidance.  The chance for precip
will be spread over a few days at least into Thursday as another
surface low transverses south of the CWA.  Overall confidence in
system is high, with total QPF amount confidence medium.

A short reprieve for Friday from precip before another upper level
low will move into the central US Great Plains. Another surface low
will track south of the area through MO and into central IL.  Even
thought guidance is in good agreement in the placement of this low
and wave, I have low confidence in this solution as the energy for
the system is off shore and there are still two lows to move through
the area before this one.

Past the weekend, a wave train of lows continues.  There will be
another chance for precip at the end of the period.  Confidence in
these solutions are low, that said, the pattern favors rain and more
chances of measurable precip.


.AVIATION...(For the 12Z TAFS through 12Z Tuesday Morning)
ISSUED AT 613 AM CDT Mon Mar 27 2017

Low cigs will continue through the period, and likely well beyond
Tuesday morning, as stratus covers the upper Midwest. There will
also be fog this morning, with visibility near minimums for short
periods through 15Z, followed by generally 3 to 6 miles in light
fog and some light rain, which will be mainly south of Interstate
80. Rains will end by mid afternoon, with a period of MVFR cigs
around 1500 ft lasting to mid evening, before a typical drop in
cigs overnight to lower IFR ranges of 600 ft to 1000 ft. Winds
will remain light north to northeast through the entire period.




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