Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 241944

Area Forecast Discussion
National Weather Service Quad Cities IA IL
244 PM CDT Tue Apr 24 2018

Issued at 215 PM CDT Tue Apr 24 2018

Beautiful late April day in the 70s across eastern Iowa and
northwestern Illinois. The air is quite dry with dewpoints in the
30s and 20s and relative humidity only around 20 percent.


.SHORT TERM...(This Evening through Wednesday)
ISSUED AT 215 PM CDT Tue Apr 24 2018

This Evening through Wednesday

Quiet weather continues as one shortwave trough misses the area to
the northeast and another stays well to the southwest. After
overnight lows in the 40s, we`ll rebound to the lower 60s on
average by Wednesday afternoon.

.LONG TERM...(Wednesday Night through Tuesday)
ISSUED AT 215 PM CDT Tue Apr 24 2018

Wednesday Night through Saturday

Seasonable weather expected with highs generally in the 60s and
lows in the 40s and 30s. Scattered light showers are possible
Thursday night when a weak cold front moves through. The front has
little in the way of upper dynamics associated with it, so it
appears most locations will receive little to no rain.

Sunday On

Significant 500mb height rises late in the weekend portend a big
warm-up with widespread 70s forecast by early next week. The
above average temperatures will come with periods of gusty
southwest winds. Better chances for showers and thunderstorms may
arrive later in the week as a low pressure system develops in the
Central Plains and PWATs across the Midwest rise above 1 inch.


.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
ISSUED AT 1204 PM CDT Tue Apr 24 2018

VFR conditions to prevail through the period with some periods of mostly
mid clouds tonight into Wednesday. Winds will be northerly at 5 to 10+
mph through the period.


Issued at 215 PM CDT Tue Apr 24 2018

Main Message: Expect the Mississippi River to begin rising soon.
Rises will continue through the first part of May, with a high
potential for minor and possibly moderate flooding in some areas.
Look for additional information later this week when there is a
better grasp of timing and what level of impacts are expected.

Looking at the latest visible satellite and this morning`s
information from the NOHRSC, the only snow that remains in the Upper
Mississippi River Valley is across parts of northern WI, with
generally 1 to 2 inches of Snow Water Equivalent (SWE). This is
reduced from the widespread 2 to 4 inches (and up to 6 inches in
some areas) across MN and WI a week ago. Considering the amount of
snow that was on the ground and the lack of recent rainfall, the
melt has been nearly ideal.

As the water from the snowmelt works its way through the tributaries
and into the Mississippi River and then downstream through the local
area (IA/IL/MO), forecasts will continue to rise in the coming
weeks. Unless heavy rain occurs, it is anticipated that the
Mississippi River from Dubuque downstream through Gregory Landing
could expect crests in the 10 to 18 day time range, which is the 1st
to 2nd week in May. Exactly how high the river will get is still
unknown, but it is certainly possible that several sites will at
least see minor flooding occur. While this is a routing scenario,
the fact that this is occurring in late April and early May could
cause some increased attenuation as green-up is underway to keep
levels a bit lower than would typically be expected. And again, any
rainfall could deviate how this occurs.




LONG TERM...Uttech
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