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fxus63 kmpx 171925 
afdmpx

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
225 PM CDT sun may 17 2020

Short term...(this evening through Monday night)
issued at 225 PM CDT sun may 17 2020

Not too much new left to say about today's system, it's obviously
been a soaker across the area and has a bit of time left before it
departs. Latest water vapor imagery shows an excellent circulation
centered just to our south, slowly making its way southeastward.
The main flow of good moisture from the Gulf has shifted east, but
we continue to see come cold conveyor belt moisture works westward
across the forecast area. Rap pv analysis show the upper anomaly
dipping down to below 500 mb, which is definitely helping to
enhance a deep zone of upper level divergence as well as a
peristent area of low- to mid-level frontogenesis. All of this
will shift east tonight, with rain ending from northwest to
southeast. Clouds will stick around through the night for most of
the area, then slowly work out through the day on Monday. Knocked
down temperatures some for Monday given the overall slower
progression of the system.

Long term...(tuesday through sunday)
issued at 225 PM CDT sun may 17 2020

The expected trend toward a slower overall evolution of the large
scale pattern has persisted in the guidance for this week. With
the flow becoming more amplified some slowing was to be expected.
And with the upper low currently near US cutting off over the Ohio
and Tennessee valleys (south of the larger scale ridge), the
pattern will be fairly locked up for the week. In terms of the
forecast, the main impact is to slow the arrival of warmer
temperatures, with any 80 degree readings looking like they will
hold off until at least Friday or Saturday for most locations. In
addition, precipitation will have a tough time working back into
the area as we see successive impulses eject from the western
trough and shear out as the try to move eastward into the large
scale ridge. Most of the area probably won't see any meaningful
precipitation return until the weekend, but did start to bring
chance pops back in as early as Thursday night across the west to
account for some significant differences in the gefs and eps
members (which are inherently accounted for in the nbm solution
which was generally followed).

&&

Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1220 PM CDT sun may 17 2020

Upper low continues to crank away to our south, helping to produce
precipitation across much of the area, along with MVFR and IFR
ceilings and visibilities. Conditions will gradually improve late
this afternoon into this evening as precipitation shifts south and
eastward with the upper and surface lows. Ceilings should rise
some and break up a bit from northwest to southeast. However,
where clouds break up we could see some redevelopment late tonight
given the ample low level moisture. Ceilings will remain around
for a good part of the day across the south and east on Monday,
but should be VFR. Gusty northeast winds will eventually die down
late tonight and Monday.

Kmsp...main uncertainty is how long we'll keep lower ceilings
around into this evening and whether we'll see some return later
tonight. Wind direction looks locked into an unfavorable direction
for the period, but should decrease a bit in speed as Monday
progresses.

/Outlook for kmsp/
Monday night...VFR expected. Northeast wind 5 to 15 kt becoming
east.
Tuesday...VFR expected. East wind around 10 kt becoming southeast.
Tuesday night...VFR expected. Southeast wind less than 10 kt.
Wednesday through Thursday...VFR expected. Southeast wind around
10 kt.



&&

Mpx watches/warnings/advisories...
WI...none.
Minnesota...none.
&&

$$

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