Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 241758

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1258 PM CDT SUN JUL 24 2016

.SHORT TERM...(Today and tonight)
Issued at 424 AM CDT Sun Jul 24 2016

A cold front had pushed passed MSP at 4 am and will sweep across
our WI FA before daybreak. Showers and thunderstorms were confined
to areas of west central WI to the north of I-94 through daybreak
with any lingering showers ending by 14z near Ladysmith. The
balance of Sunday will be dry as high pressure begins building in
from the Western High Plains.

The main concern in the short term surrounds the high
temperature forecast for today. Mix-down from 825 mb shows highs
in the mid 80s from west central MN through the Twin Cities
to Eau Claire with lower 80s to the north. This agrees with
output from various MOS products. However, mix-down indicates
highs more in the upper 80s near the I-90 corridor. This does not
agree very well with MOS nor bias corrected guidance which
suggests highs only around 80, which is only about 5 degrees from
where readings are early this morning. For the forecast, went with
a blend with more emphasis on the bias corrected guidance which
yielded highs in the lower 80s.

Nice night tonight as the high pressure system settles overhead by
daybreak Monday. Lows in the upper 50s to lower 60s were continued
with middle 60s in the Twin Cities.

.LONG TERM...(Monday through Saturday)
Issued at 424 AM CDT Sun Jul 24 2016

Next week will be dominated a split zonal flow, temperatures near
normal, and on and off chances for showers and thunderstorms, though
chances for severe weather or excessive rainfall look low.

The long term will start with a beautiful day Monday as high
pressure slides across the area, with sunny skies dominating. We
begin to see return flow setup Monday night, but the models have
continued to trend showing the llj going up through SoDak and
curling up into the Red River Valley, with precip chances remaining
west and northwest of the MPX CWA Monday night. In fact, the models
are continuing to slow down when the next weak boundary arrives,
with most of Tuesday looking dry as well, with rain chances not
starting to pickup a bit more until Tuesday night. After Tuesday
night, we get into a rather dirty zonal flow through Saturday that
will be turning toward the NW with time. During this period, in each
12 hour day/night period you can find a model that is dry and one
that would produce scattered precipitation, which results in the
continuous chance pops from Tuesday night through Saturday. Though
through this time, the greatest coverage shows up in the afternoon
periods, indicating most of what we see next week will be diurnally
driven. In addition, a general decrease in shower coverage is
expected the deeper into the week we get as persistent northeast
flow from a high centered to the north of Lake Superior will result
in continuously drier low level air coming down from the northeast.
Forcing with any one of the waves is weak, there are really no
strong llj signatures, and MUCAPE is generally under 2k j/kg, so we
are not expecting much in the way of severe weather.

Given the zonal flow, we will see no significant pushes of warm or cold
air or moist or dry air, so temperatures near normal are expected
with dewpoints remaining in the 60s. Model spread for temperature is
not all that great, so stayed with blended guidance.


.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1258 PM CDT Sun Jul 24 2016

Main concern this afternoon will be gusty w-nw winds. Some
locations have been gusting around 20 knots during the late
morning, and that should persist through the afternoon before
tapering off around sunset. Winds will increase a little bit late
tomorrow morning, but not as much as today.

Stream of accas from southern South Dakota and Nebraska will
persist across southern MN and into Wisconsin. The accas do have
some spotty showers but it is doubtful the precip will make it
beyond southwest MN as the mid/upper flow suggests it will drop
back into Iowa.

Few additional concerns. WNW gusts around 20 knots this afternoon
should taper off a little before sunset with loss of heating. High
pressure will be over the area on Monday with winds remaining
below 10 knots with no expectation of gusts.


Tue...VFR. Slgt Chance afternoon TSRA, better chance Tuesday evening.
      Winds SW 5 kts.
Wed...VFR. Chance TSRA. Winds S 5 kts.
Thu...VFR. Chance TSRA. Winds NE 5 kts.


.MPX Watches/Warnings/Advisories...


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