Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 151104

Area Forecast Discussion
National Weather Service Quad Cities IA IL
604 AM CDT Thu Mar 15 2018


Issued at 254 AM CDT Thu Mar 15 2018

Weak cold front sagging through the southern cwa early this AM.
Front ended up slowing considerably than was forecast yesterday, as
incoming high pressure is notably weaker and further northwest.
Therefore, temperatures are not as cold with readings still at or
above freezing in many locations, with even a few lower 40s still
holding on across the far south ahead of the front. Otherwise,
tranquil conditions being found with generally clear skies and light
W/NW winds. Dry and tranquil conditions will be found into tonight
with high pressure ridging firmly in control. By late tonight and
especially throughout Friday precipitation chances will increase
and spread in from the south/west ahead of low pressure translating
eastward from the Plains.


.SHORT TERM...(Today and Tonight)
ISSUED AT 254 AM CDT Thu Mar 15 2018

Weak cold front will continue to shift south of the area today, as
upstream high pressure over the Dakotas and MN builds southward.
This mean another day of sunshine, but temperatures will be
slightly cooler with northerly winds. Despite this expect readings
still around normal for mid March. I actually favored near the
warm side of guidance for highs today given that the early AM
start is not as cold as previous forecast, and with continued dry
ground and sunshine. This generally equates to upper 40s north to
mid 50s south.

Clouds will thicken mainly across the south half or so tonight
in developing warm advection/isentropic ascent ahead of low
pressure emerging into the Plains. This lift will be battling
strengthening low level dry easterly flow, and expecting the dry
air to largely win out. The exception being potentially the far
southern cwa where there will be a chance of some very light rain
possibly mixed with sleet. Easterly winds should strengthen into
10-20 mph with higher gusts west of the Mississippi. This will
pull in lower dewpoints from western Great Lakes ridge axis, and
with clear to partly cloudy skies I sided near or just below the
cold side of guidance on lows along/n of I-80 with many areas in
the range of 20-25 degrees. Expect a gradient toward warmer readings
into the lower 30s far south due to clouds.

.LONG TERM...(Friday through Wednesday)
ISSUED AT 254 AM CDT Thu Mar 15 2018

Winter will remind us that it is still around in the extended.
Models have solidified on a solution for Friday into Saturday across
the area.  Nighttime snow, freezing rain and/or sleet will give way
to rain during the day and melting of any frozen precip left. Sunday
remains a quiet day before another surface low tracks south of the
area Monday and brings more precipitation to the area once again.
After this system, temperatures return to the 40s and quiet weather
is expected.

Friday, overall H5 system and closed H85 low filling across the area
will keep strong WAA out of the area.  This makes for a tricky
forecast as surface temps will be around freezing and likely not
following a diurnal trend overnight.  During the day on Friday,
temperatures will be warm enough for all rain.  As the sunsets,
temperatures will start to drop.  A lack of moisture will lead to
wetbulbing of temps.   With warmer surface temperatures, road
surfaces may stay warm enough to stop much accumulation of ice on
them.  Any ice accumulation would be on elevated surfaces. Overall
current QPF is low and expected impacts from the setup appear low.
If QPF begins to trend higher, then we could see a good shot of
icing across central zones. Across the NE, profiles remain conducive
for heavy wet snow. Up to 1.5 inches of snow is now forecast for
this area.  Saturday, some guidance lags precip into the late AM.
With cooler air being ushered in, there could be a chance for more
freezing rain into the late morning Saturday.  Those planning on
traveling Saturday AM should pay attention to future forecasts.

Sunday, nudged highs up slightly as operational guidance is warmer
than the blends.  Sunday should be a nice day from a sensible
weather stand point.

Monday looks like a similar setup as Friday into Saturday.  The only
difference is that the latest runs of guidance keep most of the
precip out of area.  Blended pops still have some QPF and thus POPs
for Monday. Currently have low confidence in this system.


.AVIATION...(For the 12Z TAFS through 12Z Friday Morning)
ISSUED AT 559 AM CDT Thu Mar 15 2018

Patchy fog with MVFR visibilities will be found at KCID through
sunrise, and possible at KMLI as well. Otherwise, VFR conditions
expected to dominate with eventually increasing mid/high clouds
tonight ahead of a storm system emerging into the Plains. Any
light precipitation is expected to stay southwest of the terminals
through 12z Fri. Winds tonight will increase from the E/NE at
10-20 kts.




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